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Publisher: Elsevier   (Total: 3183 journals)

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Showing 1 - 200 of 3183 Journals sorted alphabetically
Academic Pediatrics     Hybrid Journal   (Followers: 38, SJR: 1.655, CiteScore: 2)
Academic Radiology     Hybrid Journal   (Followers: 26, SJR: 1.015, CiteScore: 2)
Accident Analysis & Prevention     Partially Free   (Followers: 102, SJR: 1.462, CiteScore: 3)
Accounting Forum     Hybrid Journal   (Followers: 28, SJR: 0.932, CiteScore: 2)
Accounting, Organizations and Society     Hybrid Journal   (Followers: 40, SJR: 1.771, CiteScore: 3)
Achievements in the Life Sciences     Open Access   (Followers: 7)
Acta Anaesthesiologica Taiwanica     Open Access   (Followers: 6)
Acta Astronautica     Hybrid Journal   (Followers: 436, SJR: 0.758, CiteScore: 2)
Acta Automatica Sinica     Full-text available via subscription   (Followers: 2)
Acta Biomaterialia     Hybrid Journal   (Followers: 28, SJR: 1.967, CiteScore: 7)
Acta Colombiana de Cuidado Intensivo     Full-text available via subscription   (Followers: 3)
Acta de Investigación Psicológica     Open Access   (Followers: 3)
Acta Ecologica Sinica     Open Access   (Followers: 11, SJR: 0.18, CiteScore: 1)
Acta Histochemica     Hybrid Journal   (Followers: 5, SJR: 0.661, CiteScore: 2)
Acta Materialia     Hybrid Journal   (Followers: 311, SJR: 3.263, CiteScore: 6)
Acta Mathematica Scientia     Full-text available via subscription   (Followers: 5, SJR: 0.504, CiteScore: 1)
Acta Mechanica Solida Sinica     Full-text available via subscription   (Followers: 9, SJR: 0.542, CiteScore: 1)
Acta Oecologica     Hybrid Journal   (Followers: 12, SJR: 0.834, CiteScore: 2)
Acta Otorrinolaringologica (English Edition)     Full-text available via subscription  
Acta Otorrinolaringológica Española     Full-text available via subscription   (Followers: 2, SJR: 0.307, CiteScore: 0)
Acta Pharmaceutica Sinica B     Open Access   (Followers: 1, SJR: 1.793, CiteScore: 6)
Acta Poética     Open Access   (Followers: 4, SJR: 0.101, CiteScore: 0)
Acta Psychologica     Hybrid Journal   (Followers: 26, SJR: 1.331, CiteScore: 2)
Acta Sociológica     Open Access   (Followers: 1)
Acta Tropica     Hybrid Journal   (Followers: 6, SJR: 1.052, CiteScore: 2)
Acta Urológica Portuguesa     Open Access  
Actas Dermo-Sifiliograficas     Full-text available via subscription   (Followers: 3, SJR: 0.374, CiteScore: 1)
Actas Dermo-Sifiliográficas (English Edition)     Full-text available via subscription   (Followers: 2)
Actas Urológicas Españolas     Full-text available via subscription   (Followers: 3, SJR: 0.344, CiteScore: 1)
Actas Urológicas Españolas (English Edition)     Full-text available via subscription   (Followers: 1)
Actualites Pharmaceutiques     Full-text available via subscription   (Followers: 7, SJR: 0.19, CiteScore: 0)
Actualites Pharmaceutiques Hospitalieres     Full-text available via subscription   (Followers: 3)
Acupuncture and Related Therapies     Hybrid Journal   (Followers: 8)
Acute Pain     Full-text available via subscription   (Followers: 15, SJR: 2.671, CiteScore: 5)
Ad Hoc Networks     Hybrid Journal   (Followers: 11, SJR: 0.53, CiteScore: 4)
Addictive Behaviors     Hybrid Journal   (Followers: 18, SJR: 1.29, CiteScore: 3)
Addictive Behaviors Reports     Open Access   (Followers: 9, SJR: 0.755, CiteScore: 2)
Additive Manufacturing     Hybrid Journal   (Followers: 11, SJR: 2.611, CiteScore: 8)
Additives for Polymers     Full-text available via subscription   (Followers: 23)
Advanced Drug Delivery Reviews     Hybrid Journal   (Followers: 183, SJR: 4.09, CiteScore: 13)
Advanced Engineering Informatics     Hybrid Journal   (Followers: 12, SJR: 1.167, CiteScore: 4)
Advanced Powder Technology     Hybrid Journal   (Followers: 17, SJR: 0.694, CiteScore: 3)
Advances in Accounting     Hybrid Journal   (Followers: 9, SJR: 0.277, CiteScore: 1)
Advances in Agronomy     Full-text available via subscription   (Followers: 17, SJR: 2.384, CiteScore: 5)
Advances in Anesthesia     Full-text available via subscription   (Followers: 29, SJR: 0.126, CiteScore: 0)
Advances in Antiviral Drug Design     Full-text available via subscription   (Followers: 2)
Advances in Applied Mathematics     Full-text available via subscription   (Followers: 12, SJR: 0.992, CiteScore: 1)
Advances in Applied Mechanics     Full-text available via subscription   (Followers: 12, SJR: 1.551, CiteScore: 4)
Advances in Applied Microbiology     Full-text available via subscription   (Followers: 24, SJR: 2.089, CiteScore: 5)
Advances In Atomic, Molecular, and Optical Physics     Full-text available via subscription   (Followers: 15, SJR: 0.572, CiteScore: 2)
Advances in Biological Regulation     Hybrid Journal   (Followers: 4, SJR: 2.61, CiteScore: 7)
Advances in Botanical Research     Full-text available via subscription   (Followers: 2, SJR: 0.686, CiteScore: 2)
Advances in Cancer Research     Full-text available via subscription   (Followers: 34, SJR: 3.043, CiteScore: 6)
Advances in Carbohydrate Chemistry and Biochemistry     Full-text available via subscription   (Followers: 9, SJR: 1.453, CiteScore: 2)
Advances in Catalysis     Full-text available via subscription   (Followers: 5, SJR: 1.992, CiteScore: 5)
Advances in Cell Aging and Gerontology     Full-text available via subscription   (Followers: 5)
Advances in Cellular and Molecular Biology of Membranes and Organelles     Full-text available via subscription   (Followers: 14)
Advances in Chemical Engineering     Full-text available via subscription   (Followers: 29, SJR: 0.156, CiteScore: 1)
Advances in Child Development and Behavior     Full-text available via subscription   (Followers: 11, SJR: 0.713, CiteScore: 1)
Advances in Chronic Kidney Disease     Full-text available via subscription   (Followers: 10, SJR: 1.316, CiteScore: 2)
Advances in Clinical Chemistry     Full-text available via subscription   (Followers: 26, SJR: 1.562, CiteScore: 3)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 20, SJR: 1.977, CiteScore: 8)
Advances in Computers     Full-text available via subscription   (Followers: 14, SJR: 0.205, CiteScore: 1)
Advances in Dermatology     Full-text available via subscription   (Followers: 15)
Advances in Developmental Biology     Full-text available via subscription   (Followers: 13)
Advances in Digestive Medicine     Open Access   (Followers: 12)
Advances in DNA Sequence-Specific Agents     Full-text available via subscription   (Followers: 7)
Advances in Drug Research     Full-text available via subscription   (Followers: 26)
Advances in Ecological Research     Full-text available via subscription   (Followers: 43, SJR: 2.524, CiteScore: 4)
Advances in Engineering Software     Hybrid Journal   (Followers: 29, SJR: 1.159, CiteScore: 4)
Advances in Experimental Biology     Full-text available via subscription   (Followers: 8)
Advances in Experimental Social Psychology     Full-text available via subscription   (Followers: 51, SJR: 5.39, CiteScore: 8)
Advances in Exploration Geophysics     Full-text available via subscription   (Followers: 1)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 9)
Advances in Food and Nutrition Research     Full-text available via subscription   (Followers: 65, SJR: 0.591, CiteScore: 2)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 17)
Advances in Genetics     Full-text available via subscription   (Followers: 21, SJR: 1.354, CiteScore: 4)
Advances in Genome Biology     Full-text available via subscription   (Followers: 10, SJR: 12.74, CiteScore: 13)
Advances in Geophysics     Full-text available via subscription   (Followers: 7, SJR: 1.193, CiteScore: 3)
Advances in Heat Transfer     Full-text available via subscription   (Followers: 26, SJR: 0.368, CiteScore: 1)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 11, SJR: 0.749, CiteScore: 3)
Advances in Human Factors/Ergonomics     Full-text available via subscription   (Followers: 25)
Advances in Imaging and Electron Physics     Full-text available via subscription   (Followers: 3, SJR: 0.193, CiteScore: 0)
Advances in Immunology     Full-text available via subscription   (Followers: 37, SJR: 4.433, CiteScore: 6)
Advances in Inorganic Chemistry     Full-text available via subscription   (Followers: 10, SJR: 1.163, CiteScore: 2)
Advances in Insect Physiology     Full-text available via subscription   (Followers: 2, SJR: 1.938, CiteScore: 3)
Advances in Integrative Medicine     Hybrid Journal   (Followers: 6, SJR: 0.176, CiteScore: 0)
Advances in Intl. Accounting     Full-text available via subscription   (Followers: 3)
Advances in Life Course Research     Hybrid Journal   (Followers: 9, SJR: 0.682, CiteScore: 2)
Advances in Lipobiology     Full-text available via subscription   (Followers: 1)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 8)
Advances in Marine Biology     Full-text available via subscription   (Followers: 21, SJR: 0.88, CiteScore: 2)
Advances in Mathematics     Full-text available via subscription   (Followers: 14, SJR: 3.027, CiteScore: 2)
Advances in Medical Sciences     Hybrid Journal   (Followers: 8, SJR: 0.694, CiteScore: 2)
Advances in Medicinal Chemistry     Full-text available via subscription   (Followers: 6)
Advances in Microbial Physiology     Full-text available via subscription   (Followers: 5, SJR: 1.158, CiteScore: 3)
Advances in Molecular and Cell Biology     Full-text available via subscription   (Followers: 24)
Advances in Molecular and Cellular Endocrinology     Full-text available via subscription   (Followers: 8)
Advances in Molecular Toxicology     Full-text available via subscription   (Followers: 7, SJR: 0.182, CiteScore: 0)
Advances in Nanoporous Materials     Full-text available via subscription   (Followers: 5)
Advances in Oncobiology     Full-text available via subscription   (Followers: 2)
Advances in Organ Biology     Full-text available via subscription   (Followers: 2)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 18, SJR: 1.875, CiteScore: 4)
Advances in Parallel Computing     Full-text available via subscription   (Followers: 7, SJR: 0.174, CiteScore: 0)
Advances in Parasitology     Full-text available via subscription   (Followers: 5, SJR: 1.579, CiteScore: 4)
Advances in Pediatrics     Full-text available via subscription   (Followers: 27, SJR: 0.461, CiteScore: 1)
Advances in Pharmaceutical Sciences     Full-text available via subscription   (Followers: 19)
Advances in Pharmacology     Full-text available via subscription   (Followers: 17, SJR: 1.536, CiteScore: 3)
Advances in Physical Organic Chemistry     Full-text available via subscription   (Followers: 9, SJR: 0.574, CiteScore: 1)
Advances in Phytomedicine     Full-text available via subscription  
Advances in Planar Lipid Bilayers and Liposomes     Full-text available via subscription   (Followers: 3, SJR: 0.109, CiteScore: 1)
Advances in Plant Biochemistry and Molecular Biology     Full-text available via subscription   (Followers: 10)
Advances in Plant Pathology     Full-text available via subscription   (Followers: 6)
Advances in Porous Media     Full-text available via subscription   (Followers: 5)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 19)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 20, SJR: 0.791, CiteScore: 2)
Advances in Psychology     Full-text available via subscription   (Followers: 67)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 6, SJR: 0.371, CiteScore: 1)
Advances in Radiation Oncology     Open Access   (Followers: 1, SJR: 0.263, CiteScore: 1)
Advances in Small Animal Medicine and Surgery     Hybrid Journal   (Followers: 3, SJR: 0.101, CiteScore: 0)
Advances in Space Biology and Medicine     Full-text available via subscription   (Followers: 6)
Advances in Space Research     Full-text available via subscription   (Followers: 421, SJR: 0.569, CiteScore: 2)
Advances in Structural Biology     Full-text available via subscription   (Followers: 5)
Advances in Surgery     Full-text available via subscription   (Followers: 13, SJR: 0.555, CiteScore: 2)
Advances in the Study of Behavior     Full-text available via subscription   (Followers: 37, SJR: 2.208, CiteScore: 4)
Advances in Veterinary Medicine     Full-text available via subscription   (Followers: 20)
Advances in Veterinary Science and Comparative Medicine     Full-text available via subscription   (Followers: 15)
Advances in Virus Research     Full-text available via subscription   (Followers: 6, SJR: 2.262, CiteScore: 5)
Advances in Water Resources     Hybrid Journal   (Followers: 53, SJR: 1.551, CiteScore: 3)
Aeolian Research     Hybrid Journal   (Followers: 6, SJR: 1.117, CiteScore: 3)
Aerospace Science and Technology     Hybrid Journal   (Followers: 385, SJR: 0.796, CiteScore: 3)
AEU - Intl. J. of Electronics and Communications     Hybrid Journal   (Followers: 8, SJR: 0.42, CiteScore: 2)
African J. of Emergency Medicine     Open Access   (Followers: 6, SJR: 0.296, CiteScore: 0)
Ageing Research Reviews     Hybrid Journal   (Followers: 12, SJR: 3.671, CiteScore: 9)
Aggression and Violent Behavior     Hybrid Journal   (Followers: 476, SJR: 1.238, CiteScore: 3)
Agri Gene     Hybrid Journal   (Followers: 1, SJR: 0.13, CiteScore: 0)
Agricultural and Forest Meteorology     Hybrid Journal   (Followers: 18, SJR: 1.818, CiteScore: 5)
Agricultural Systems     Hybrid Journal   (Followers: 31, SJR: 1.156, CiteScore: 4)
Agricultural Water Management     Hybrid Journal   (Followers: 44, SJR: 1.272, CiteScore: 3)
Agriculture and Agricultural Science Procedia     Open Access   (Followers: 4)
Agriculture and Natural Resources     Open Access   (Followers: 3)
Agriculture, Ecosystems & Environment     Hybrid Journal   (Followers: 58, SJR: 1.747, CiteScore: 4)
Ain Shams Engineering J.     Open Access   (Followers: 5, SJR: 0.589, CiteScore: 3)
Air Medical J.     Hybrid Journal   (Followers: 8, SJR: 0.26, CiteScore: 0)
AKCE Intl. J. of Graphs and Combinatorics     Open Access   (SJR: 0.19, CiteScore: 0)
Alcohol     Hybrid Journal   (Followers: 12, SJR: 1.153, CiteScore: 3)
Alcoholism and Drug Addiction     Open Access   (Followers: 12)
Alergologia Polska : Polish J. of Allergology     Full-text available via subscription   (Followers: 1)
Alexandria Engineering J.     Open Access   (Followers: 2, SJR: 0.604, CiteScore: 3)
Alexandria J. of Medicine     Open Access   (Followers: 1, SJR: 0.191, CiteScore: 1)
Algal Research     Partially Free   (Followers: 11, SJR: 1.142, CiteScore: 4)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 2)
Allergologia et Immunopathologia     Full-text available via subscription   (Followers: 1, SJR: 0.504, CiteScore: 1)
Allergology Intl.     Open Access   (Followers: 5, SJR: 1.148, CiteScore: 2)
Alpha Omegan     Full-text available via subscription   (SJR: 3.521, CiteScore: 6)
ALTER - European J. of Disability Research / Revue Européenne de Recherche sur le Handicap     Full-text available via subscription   (Followers: 10, SJR: 0.201, CiteScore: 1)
Alzheimer's & Dementia     Hybrid Journal   (Followers: 53, SJR: 4.66, CiteScore: 10)
Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring     Open Access   (Followers: 6, SJR: 1.796, CiteScore: 4)
Alzheimer's & Dementia: Translational Research & Clinical Interventions     Open Access   (Followers: 6, SJR: 1.108, CiteScore: 3)
Ambulatory Pediatrics     Hybrid Journal   (Followers: 5)
American Heart J.     Hybrid Journal   (Followers: 58, SJR: 3.267, CiteScore: 4)
American J. of Cardiology     Hybrid Journal   (Followers: 63, SJR: 1.93, CiteScore: 3)
American J. of Emergency Medicine     Hybrid Journal   (Followers: 46, SJR: 0.604, CiteScore: 1)
American J. of Geriatric Pharmacotherapy     Full-text available via subscription   (Followers: 12)
American J. of Geriatric Psychiatry     Hybrid Journal   (Followers: 14, SJR: 1.524, CiteScore: 3)
American J. of Human Genetics     Hybrid Journal   (Followers: 37, SJR: 7.45, CiteScore: 8)
American J. of Infection Control     Hybrid Journal   (Followers: 29, SJR: 1.062, CiteScore: 2)
American J. of Kidney Diseases     Hybrid Journal   (Followers: 36, SJR: 2.973, CiteScore: 4)
American J. of Medicine     Hybrid Journal   (Followers: 50)
American J. of Medicine Supplements     Full-text available via subscription   (Followers: 3, SJR: 1.967, CiteScore: 2)
American J. of Obstetrics and Gynecology     Hybrid Journal   (Followers: 254, SJR: 2.7, CiteScore: 4)
American J. of Ophthalmology     Hybrid Journal   (Followers: 66, SJR: 3.184, CiteScore: 4)
American J. of Ophthalmology Case Reports     Open Access   (Followers: 5, SJR: 0.265, CiteScore: 0)
American J. of Orthodontics and Dentofacial Orthopedics     Full-text available via subscription   (Followers: 6, SJR: 1.289, CiteScore: 1)
American J. of Otolaryngology     Hybrid Journal   (Followers: 25, SJR: 0.59, CiteScore: 1)
American J. of Pathology     Hybrid Journal   (Followers: 32, SJR: 2.139, CiteScore: 4)
American J. of Preventive Medicine     Hybrid Journal   (Followers: 28, SJR: 2.164, CiteScore: 4)
American J. of Surgery     Hybrid Journal   (Followers: 39, SJR: 1.141, CiteScore: 2)
American J. of the Medical Sciences     Hybrid Journal   (Followers: 12, SJR: 0.767, CiteScore: 1)
Ampersand : An Intl. J. of General and Applied Linguistics     Open Access   (Followers: 7)
Anaerobe     Hybrid Journal   (Followers: 4, SJR: 1.144, CiteScore: 3)
Anaesthesia & Intensive Care Medicine     Full-text available via subscription   (Followers: 66, SJR: 0.138, CiteScore: 0)
Anaesthesia Critical Care & Pain Medicine     Full-text available via subscription   (Followers: 24, SJR: 0.411, CiteScore: 1)
Anales de Cirugia Vascular     Full-text available via subscription   (Followers: 1)
Anales de Pediatría     Full-text available via subscription   (Followers: 3, SJR: 0.277, CiteScore: 0)
Anales de Pediatría (English Edition)     Full-text available via subscription  
Anales de Pediatría Continuada     Full-text available via subscription  
Analytic Methods in Accident Research     Hybrid Journal   (Followers: 5, SJR: 4.849, CiteScore: 10)
Analytica Chimica Acta     Hybrid Journal   (Followers: 44, SJR: 1.512, CiteScore: 5)
Analytica Chimica Acta : X     Open Access  
Analytical Biochemistry     Hybrid Journal   (Followers: 210, SJR: 0.633, CiteScore: 2)
Analytical Chemistry Research     Open Access   (Followers: 13, SJR: 0.411, CiteScore: 2)
Analytical Spectroscopy Library     Full-text available via subscription   (Followers: 14)
Anesthésie & Réanimation     Full-text available via subscription   (Followers: 2)
Anesthesiology Clinics     Full-text available via subscription   (Followers: 25, SJR: 0.683, CiteScore: 2)
Angiología     Full-text available via subscription   (SJR: 0.121, CiteScore: 0)
Angiologia e Cirurgia Vascular     Open Access   (Followers: 1, SJR: 0.111, CiteScore: 0)
Animal Behaviour     Hybrid Journal   (Followers: 222, SJR: 1.58, CiteScore: 3)
Animal Feed Science and Technology     Hybrid Journal   (Followers: 6, SJR: 0.937, CiteScore: 2)
Animal Reproduction Science     Hybrid Journal   (Followers: 7, SJR: 0.704, CiteScore: 2)

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Similar Journals
Journal Cover
American Journal of Pathology
Journal Prestige (SJR): 2.139
Citation Impact (citeScore): 4
Number of Followers: 32  
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0002-9440
Published by Elsevier Homepage  [3183 journals]
  • Non-SMC condensin I complex subunit D2 is a prognostic factor in
           triple-negative breast cancer for the ability to promote cell cycle and
           enhance invasion
    • Abstract: Publication date: Available online 12 October 2019Source: The American Journal of PathologyAuthor(s): Yajing Zhang, Fangfang Liu, Chengli Zhang, Meijing Ren, Manchao Kuang, Ting Xiao, Xuebing Di, Lin Feng, Li Fu, Shujun ChengTriple-negative breast cancer (TNBC) is a heterogeneous disease with an unfavorable prognosis and no specific targeted therapies. The role of non-SMC condensin I complex subunit D2 (NCAPD2), a regulatory subunit of the condensin I complex that mainly participates in chromosome condensation and segregation, has not been reported in cancer. We therefore evaluated the prognostic value and biological function of NCAPD2 in TNBC. The expression of NCAPD2 was studied in 179 TNBC tissues by immunohistochemistry and associations among NCAPD2 expression, clinicopathological features, and the prognosis information of TNBC patients were analyzed. The mRNA expression profiles of 99 TNBC tissues were also studied and cell biological behaviors were detected when NCAPD2 was altered in three TNBC cell lines. NCAPD2 expression was positively associated with lymph node metastasis (P = 3.84×10-06), poor overall survival (P = 0.0033), and worse disease-free survival (P = 0.0013) of TNBC patients. Moreover, knockdown of NCAPD2 might cause G2/M arrest through p53 signaling pathway, which led to proliferation inhibition, polyploid cell production and cell apoptosis, and also inhibited the invasiveness of TNBC cells. For the first time, we report the close relationship between NCAPD2 and cancer, and demonstrate that NCAPD2 plays an important role in TNBC progression and acts as an independent poor prognostic factor and a potential therapeutic target for TNBC.
  • Intestinal epithelial chemokine (C-C motif) ligand 7 overexpression
           enhances acetaminophen-induced hepatotoxicity in mice
    • Abstract: Publication date: Available online 11 October 2019Source: The American Journal of PathologyAuthor(s): Mengwei Niu, Zhihong Luo, Shenhai Gong, Sanda Win, Neil Kaplowitz, Yong Jiang, Peng Chen Acetaminophen (APAP) overdose–induced hepatotoxicity is the leading cause of drug-induced liver injury worldwide. The related injury pathogenesis is mainly focused on the liver. Here, we report that gut barrier disruption may also be involved in APAP hepatotoxicity. APAP administration led to gut leakiness and colonic epithelial chemokine (C-C motif) ligand 7 (CCL7) up-regulation. Intestinal epithelial cell (IEC)-specific CCL7 transgenic mice (CCL7tgIEC mice) showed markedly increased myosin light chain kinase (MLCK) phosphorylation and elevated gut permeability and bacterial translocation into the liver compared to wild-type mice. Global transcriptome analysis revealed that the expression of hepatic pro-inflammatory genes was enhanced in CCL7tgIEC mice compared to wild-type animals. Moreover, CCL7 overexpression in intestinal epithelial cells significantly augmented APAP-induced acute liver injury. Our data provides new evidence that dysfunction of CCL7-mediated gut barrier integrity may be an important contributor to APAP-induced hepatotoxicity.
  • Involvement of Transcription Factor 21 in the Pathogenesis of Fibrosis in
    • Abstract: Publication date: Available online 11 October 2019Source: The American Journal of PathologyAuthor(s): Umida Ganieva, Tomoko Nakamura, Satoko Osuka, Bayasula, Natsuki Nakanishi, Yukiyo Kasahara, Nobuyoshi Takasaki, Ayako Muraoka, Shotaro Hayashi, Takashi Nagai, Tomohiko Murase, Maki Goto, Akira Iwase, Fumitaka Kikkawa Repeated tissue injury and repair, and fibrosis play a pivotal role in endometriosis. Fibrotic tissue consists of extracellular matrix proteins, regulated by transcriptional factors promoting cell proliferation and survival. Periostin is one of the putative key extracellular matrix proteins. This study aimed to determine whether transcription factor 21 (TCF21) is involved in the development of endometriosis as an upstream regulatory gene of periostin. Formalin-fixed, paraffin-embedded tissue samples (normal endometrium of women without endometriosis, NE; eutopic endometrium of women with endometriosis, EE; ovarian endometriosis, OE; deep infiltrating endometriosis, DIE) and respective cells were analyzed. Basal, transiently stimulated, and knocked down periostin and TCF21 concentrations in stromal cells of women with or without endometriosis were examined. Periostin and TCF21 expressions were undetected in NE, weakly positive in EE, moderately positive in OE, and strongly positive in DIE. Th2 type cytokines (interleukin-4, interleukin-13, and transforming growth factor-β1) increased the mRNA expression of periostin and TCF21. These cytokines, periostin, and TCF21 co-localized in the stroma of OE and DIE. siTCF21 suppressed periostin expression. Transfection of TCF21 plasmid vector into stromal cells of women without endometriosis, which originally expressed neither periostin nor TCF21, resulted in TCF21 and periostin expression. TCF21 and periostin are involved in the regulation of fibrosis in endometriosis. TCF21 may be a promising therapeutic target and biomarker in endometriosis.
  • RNA Expression Profiling of Lymphoepithelioma-Like Carcinoma of the
           Bladder Reveals a Basal-like Molecular Subtype
    • Abstract: Publication date: Available online 11 October 2019Source: The American Journal of PathologyAuthor(s): Ujjawal Manocha, Jordan Kardos, Sara Selitsky, Mi Zhou, Steven M. Johnson, Cori Breslauer, Jonathan I. Epstein, William Y. Kim, Sara E. WobkerLymphoepithelioma-like carcinoma of the bladder (LELC-B) is a rare subtype of urothelial carcinoma consisting of undifferentiated epithelial cells within a dense inflammatory cell infiltrate. We set out to molecularly characterize LELC-B through RNA expression profiling as well as immunohistochemistry to understand its underlying biology. Sixteen cases of LELC-B were identified at Johns Hopkins University. RNAseq was performed on 14 cases. Immunohistochemical staining for PD-L1 and mismatch repair proteins MLH1, MSH2, MSH6, and PMS2 was performed. Transcriptomic profiling of LELC-B showed that they are enriched in a basal-like phenotype, with 12 of 14 LELC-B cases correlating to the basal centroid of the BASE47 PAM classifier. Gene signature analysis confirmed the lymphocyte infiltration profile consistent with the histomorphology. LELC-B lacked features to explain the robust lymphocytic infiltrate, such as loss of mismatch repair protein expression or expression of Epstein-Barr virus transcripts. Nonetheless, PD-L1 immunohistochemistry was positive in 93% of LELC cases. Our study demonstrates that LELC-B tumors are enriched in a basal-like molecular subtype, share a high level of immune infiltration and PD-L1 expression similar to basal tumors. The basal-like phenotype is consistent with the known sensitivity of LELC-B to chemotherapy and suggests that immune checkpoint therapy should be explored in this rare disease.
  • Ferroptosis affects the progression of non-alcoholic steatohepatitis via
           the modulation of lipid peroxidation–mediated cell death in mice
    • Abstract: Publication date: Available online 11 October 2019Source: The American Journal of PathologyAuthor(s): Jing Qi, Jong-Won Kim, Zixiong Zhou, Chae Woong Lim, Bumseok Kim Oxidative stress and its-associated lipid peroxidation play a key role in non-alcoholic steatohepatitis (NASH). Ferroptosis is a recently recognized type of cell death characterized by an iron dependent and lipid peroxidation–mediated non-apoptotic cell death. We demonstrate the impact of ferroptosis on the progression of NASH induced by methionine/choline-deficient diet (MCD) feeding for 10 days. RSL-3 (a ferroptosis inducer) treatment showed decreased hepatic expression of GPX4, and conversely increased 12/15-lipoxygenase, and apoptosis inducing factor, indicating that ferroptosis plays a key role in NASH-related lipid peroxidation and its-associated cell death. Consistently, levels of serum biochemical, hepatic steatosis, inflammation, and apoptosis in MCD-fed mice were exacerbated with RSL-3 treatment. However, MCD-fed mice treated with sodium selenite (a GPX4 activator) showed increase of hepatic GPX4, accompanied by reduced NASH severity. To chelate iron, deferoxamine mesylate salt was used. Administration of deferoxamine mesylate salt significantly reduced NASH severity and abolished the harmful effects of RSL-3 in MCD-fed mice. Finally, treatment with Liproxstatin-1 (a ferroptosis inhibitor) repressed hepatic lipid peroxidation, and its associated cell death, resulting in decreased NASH severity. Consistent with the in vivo findings, modulation of ferroptosis /GPX4 affected hepatocellular death in palmitic acid–induced in vitro NASH milieu. We conclude that GPX4 and its-related ferroptosis might play a major role in the development of NASH.
  • Insights into Fibroblast Plasticity: CCN2 Is Required for Activation of
           Cancer-Associated Fibroblasts in a Murine Model of Melanoma
    • Abstract: Publication date: Available online 11 October 2019Source: The American Journal of PathologyAuthor(s): Matthew Tsang, Katherine Quesnel, Krista Vincent, James Hutchenreuther, Lynne-Marie Postovit, Andrew LeaskTumor stroma resembles a fibrotic microenvironment, being characterized by the presence of myofibroblast-like cancer-associated fibroblasts (CAFs). In wild-type mice injected with melanoma cells, we show that the stem cell transcription factor Sox2 is expressed by tumor cells and induced in CAFs derived from synthetic fibroblasts. These fibroblasts were labeled postnatally with green fluorescent protein using mice expressing a tamoxifen-dependent Cre recombinase under the control of a fibroblast-specific promoter/enhancer. Conversely, fibroblast activation was impaired in mice with a fibroblast-specific deletion of Ccn2, associated with reduced expression of alpha-smooth muscle actin and Sox2. Multipotent Sox2-expressing skin-derived precursor (SKP) spheroids were cultured from murine back skin. Using lineage tracing and flow cytometry, approximately 40% of SKPs were found to be derived from a Col1a2 origin and acquired multipotency in culture. Inhibition of mechanotransduction pathways prevented myofibroblast differentiation of SKPs and expression of Ccn2. In SKPs deleted for Ccn2, differentiation into a myofibroblast, but not an adipocyte or neuronal phenotype, was also impaired. In human melanoma, CCN2 expression was associated with a profibrotic ITGA11-expressing subset of cancer-associated fibroblasts that negatively associated with survival. Collectively, these results suggest that synthetic dermal fibroblasts possess a previously unheralded in vivo and in vitro plasticity, and that CCN2 is required for the differentiation of dermal progenitor cells into a myofibroblast/CAF phenotype and is therefore a therapeutic target in melanoma.
  • Cell of Origin and Immunological Events in the Pathogenesis of Breast
           Implant–Associated Anaplastic Large Cell Lymphoma
    • Abstract: Publication date: Available online 11 October 2019Source: The American Journal of PathologyAuthor(s): Suzanne D. Turner, Giorgio Inghirami, Roberto N. Miranda, Marshall E. KadinBreast implant–associated anaplastic large cell lymphoma (BIA-ALCL) is a CD30-positive, anaplastic lymphoma kinase–negative T-cell lymphoma. Nearly all cases have been associated with textured implants. Most cases are of effusion-limited, indolent disease, with an excellent prognosis following implant and capsule removal. However, capsular invasion and tumor mass has a more aggressive course, and a fatal outcome risk. This review summarizes the current knowledge on BIA-ALCL cell of origin and immunological factors underlying its pathogenesis. Cytokine expression profiling of BIA-ALCL cell lines and clinical specimens reveal a predominantly Th17/Th1 signature, implicating this as its cell of origin. However, a Th2 allergic inflammatory response is suggested by the presence of interleukin-13, with infiltration of eosinophils and IgE-coated mast cells in clinical specimens of BIA-ALCL. The microenvironment-induced T-cell plasticity, a factor increasingly appreciated, may partially explain these divergent results. Mutations resulting in constitutive JAK-STAT activation have been detected and associated with BIA-ALCL pathogenesis in a small number of cases. One possible scenario is that an inflammatory microenvironment stimulates an immune response followed by polyclonal expansion of Th17/Th1 cell subsets with release of inflammatory cytokines and chemokines and accumulation of seroma. JAK-STAT3 gain-of-function mutations within this pathway and others may subsequently lead to monoclonal T-cell proliferation and clinical BIA-ALCL. Current research suggests that therapies targeting JAK proteins warrant investigation in BIA-ALCL.
  • Intestinal SIRT1 Deficiency Protects Mice from Ethanol-Induced Liver
           Injury by Mitigating Ferroptosis
    • Abstract: Publication date: Available online 11 October 2019Source: The American Journal of PathologyAuthor(s): Zhou Zhou, Ting Jie Ye, Elizabeth DeCaro, Brian Buehler, Zachary Stahl, Gregory Bonavita, Michael Daniels, Min YouABSTRACTAberrant liver sirtuin 1 (SIRT1), a mammalian NAD+-dependent protein deacetylase, is implicated in the pathogenesis of alcoholic liver disease. However, the role of intestinal SIRT1 in alcoholic liver disease is presently unknown. This study investigated the involvement of intestine-specific SIRT1 in ethanol-induced liver dysfunction in mice. Ethanol feeding studies were performed on knockout mice with intestinal specific SIRT1 deletion (SIRT1iKO) and flox control (WT) mice with a chronic-plus-binge ethanol feeding protocol. Following ethanol administration, hepatic inflammation and liver injury were substantially attenuated in the SIRT1iKO mice compared to WT mice, suggesting that intestinal SIRT1 played a detrimental role in the ethanol-induced liver injury. Mechanistically, the hepatic protective effect of intestinal SIRT1 deficiency was attributable to ameliorated dysfunctional iron metabolism, increased hepatic glutathione contents, and attenuated lipid peroxidation, along with normalization of a panel of genes implicated in the ferroptosis process in the livers of ethanol-fed mice. This study demonstrates that ablation of intestinal SIRT1 protected mice from the ethanol-induced inflammation and liver damage. The protective effects of intestinal SIRT1 deficiency are mediated, at least partially, by mitigating hepatic ferroptosis. Targeting intestinal SIRT1 or dampening hepatic ferroptosis signaling may have therapeutic potential for alcoholic liver disease in humans.
  • Proresolving Mediators LXB4 and RvE1 Regulate Inflammation in Stromal
           Cells from Patients with Shoulder Tendon Tears
    • Abstract: Publication date: Available online 19 August 2019Source: The American Journal of PathologyAuthor(s): Stephanie G. Dakin, Romain A. Colas, Kim Wheway, Bridget Watkins, Louise Appleton, Jonathan Rees, Stephen Gwilym, Christopher Little, Jesmond Dalli, Andrew J. CarrTendon stromal cells isolated from patients with chronic shoulder rotator cuff tendon tears have dysregulated resolution responses. Current therapies do not address the biological processes concerned with persistent tendon inflammation; therefore, new therapeutic approaches that target tendon stromal cells are required. We examined whether two specialized proresolving mediators (SPMs), lipoxin B4 (LXB4) and resolvin E1 (RvE1), modulate the bioactive lipid mediator profiles of IL-1β–stimulated tendon cells derived from patients with shoulder tendon tears and healthy volunteers. We also examined whether LXB4 or RvE1 treatments moderated the proinflammatory phenotype of tendon tear stromal cells. Incubation of IL-1β–treated patient-derived tendon cells in LXB4 or RvE1 up-regulated concentrations of SPMs. RvE1 treatment of diseased tendon stromal cells increased 15-epi-LXB4 and regulated postaglandin F2α. LXB4 or RvE1 also induced expression of the SPM biosynthetic enzymes 12-lipoxygenase and 15-lipoxygenase. RvE1 treatment up-regulated the proresolving receptor human resolvin E1 compared with vehicle-treated cells. Incubation in LXB4 or RvE1 moderated the proinflammatory phenotype of patient-derived tendon tear cells, regulating markers of tendon inflammation, including podoplanin, CD90, phosphorylated signal transducer and activator of transcription 1, and IL-6. LXB4 and RvE1 counterregulate inflammatory processes in tendon stromal cells, supporting the role of these molecules as potential therapeutics to resolve tendon inflammation.
  • Age-related pathology associated with H1N1 A/California/07/2009 influenza
           virus infection
    • Abstract: Publication date: Available online 1 October 2019Source: The American Journal of PathologyAuthor(s): Stephanie J. Bissel, Chalise E. Carter, Guoji Wang, Scott K. Johnson, Lauren P. Lashua, Alyson Kelvin, Clayton A. Wiley, Elodie Ghedin, Ted M. Ross Influenza virus infection causes a spectrum of diseases ranging from mild upper respiratory tract infection to severe lower respiratory tract infection that can lead to diffuse alveolar damage, interstitial and airspace inflammation, or acute respiratory failure. Mechanisms instructing disease severity are not completely understood but host, viral, and bacterial factors influence disease outcome. With age being one host factor associated with higher risk of severe influenza, we investigated regional pulmonary distribution and severity of pneumonia following 2009 H1N1 influenza virus infection in newly weaned, adult, and aged ferrets to better understand age-dependent susceptibility and pathology. Aged ferrets exhibited greater weight loss and higher rates of mortality than adult ferrets, whereas the majority of newly weaned ferrets did not lose weight but had a lack of weight gain. Newly weaned ferrets exhibited minimal pneumonia, whereas adult and aged ferrets showed a spectrum of pneumonia severity. Influenza virus–induced pneumonia peaked earliest in adult ferrets, whereas aged ferrets had delayed presentation. Bronchial severity differed between groups, but bronchial pathology was comparable among all cohorts. Alveolar infection was strikingly different between groups. Newly weaned ferrets showed little alveolar cell infection. Adult and aged ferrets demonstrated alveolar infection, but aged ferrets were unable to clear infection. These different age-related pneumonia and infection patterns suggest therapeutic strategies to treat influenza should be tailored contingent on age.
  • Host Lymphotoxin-Beta Receptor Signaling is Crucial for Angiogenesis of
           Metanephric Tissue Transplanted into Lymphoid Sites
    • Abstract: Publication date: Available online 1 October 2019Source: The American Journal of PathologyAuthor(s): Maria Giovanna Francipane, Bing Han, Eric Lagasse The mouse lymph node (LN) can provide a niche to grow metanephric kidney to maturity. Here, we show that signaling through the lymphotoxin-beta receptor (LTβR) is critical for kidney organogenesis both in the LN and the omentum. By transplanting kidney rudiments either in the LNs of mice undergoing LTβR antagonist treatment or in the omenta of LTβR knockout (LTβR-/-) mice, the host LTβR signals were found to be crucial for obtaining a well-vascularized kidney graft. Indeed, defective LTβR signaling correlated with decreased expression of endothelial and angiogenic markers in kidney grafts as well as structural alterations. As the number of glomerular endothelial cells expressing the LTβR target nuclear factor κB–inducing kinase (NIK) decreased in the absence of a functional LTβR, it was speculated that an LTβR/NIK axis mediated the angiogenetic signals required for successful ectopic kidney organogenesis, given the established role of NIK in neovascularization. However, the transplantation of kidney rudiments in omenta of NIK-/- mice revealed that NIK is dispensable for ectopic kidney vascular integration and maturation. Finally, defective LTβR signaling impaired compensatory glomerular adaptation to renal mass reduction, indicating that kidney regeneration approaches, besides whole kidney reconstruction, might benefit from the presence of LTβR signals.
  • Endogenous Specialized Proresolving Mediator Profiles in a Novel
           Experimental Model of Lymphatic Obstruction and Intestinal Inflammation in
           African Green Monkeys
    • Abstract: Publication date: October 2019Source: The American Journal of Pathology, Volume 189, Issue 10Author(s): Felix Becker, Emily Romero, Jason Goetzmann, Dana L. Hasselschwert, Beth Dray, John Vanchiere, Jane Fontenot, J. Winny Yun, Paul C. Norris, Luke White, Melany Musso, Charles N. Serhan, J. Steven Alexander, Felicity N.E. GavinsChanges in the intestinal lymphatic vascular system, such as lymphatic obstruction, are characteristic features of inflammatory bowel diseases. The lymphatic vasculature forms a conduit to enable resolution of inflammation; this process is driven by specialized endogenous proresolving mediators (SPMs). To evaluate contributions of lymphatic obstruction to intestinal inflammation and to study profiles of SPMs, we generated a novel animal model of lymphatic obstruction using African green monkeys. Follow-up studies were performed at 7, 21, and 61 days. Inflammation was determined by histology. Luminex assays were performed to evaluate chemokine and cytokine levels. In addition, lipid mediator metabololipidomic profiling was performed to identify SPMs. After 7 days, lymphatic obstruction resulted in a localized inflammatory state, paralleled by an increase in inflammatory chemokines and cytokines, which were found to be up-regulated after 7 days but returned to baseline after 21 and 61 days. At the same time, a distinct pattern of SPMs was profiled, with an increase for D-series resolvins, protectins, maresins, and lipoxins at 61 days. These results indicate that intestinal lymphatic obstruction can lead to an acute inflammatory state, accompanied by an increase in proinflammatory mediators, followed by a phase of resolution, paralleled by an increase and decrease of respective SPMs.
  • Wasf3 deficiency reveals involvement in metastasis in a mouse model of
           breast cancer
    • Abstract: Publication date: Available online 19 September 2019Source: The American Journal of PathologyAuthor(s): Haiyan Qin, Sumin Lu, Muthusamy Thangaraju, John K. Cowell The WASF3 gene has been implicated in cancer cell movement, invasion, and metastasis by regulating genetic pathways important in these processes. Invasion and metastasis assays, however, are largely centered on xenograft models in immune compromised mice. To facilitate analysis of the role of WASF3 in spontaneous development of cancer cell metastasis, we generated a Wasf3 null strain by deleting exons 4 and 5, which encode essential motifs for Wasf3 function. On exposure to cre-recombinase a stop codon is generated immediately downstream in exon 6. Using a CMV-cre strain, Wasf3 was constitutively inactivated, which led to viable mice with no visible morphological or behavioral abnormalities. There was no abnormal development or function of the mouse mammary gland in the Wasf3 null mice and brain development was normal. In the MMTV-PyMT strain, which shows early onset breast cancer development and metastasis, Wasf3 is up-regulated in metastatic lesions. When this oncogene was introduced onto the Wasf3-null background, although metastasis was observed in these mice, there was a reduction in the number and size of metastatic lesions in the lungs. These data provide evidence for a role in WASF3 in development of metastasis in a spontaneous model of breast cancer.
  • Endogenous calcitonin gene–related peptide deficiency exacerbates
           postoperative lymphedema by suppressing lymphatic capillary formation and
           M2 macrophage accumulation
    • Abstract: Publication date: Available online 18 September 2019Source: The American Journal of PathologyAuthor(s): Shuhei Matsui, Megumu Tanaka, Akiko Kamiyoshi, Takayuki Sakurai, Yuka Ichikawa-Shindo, Hisaka Kawate, Kun Dai, Nanqi Cui, Yangxuan Wei, Masaaki Tanaka, Shinji Kakihara, Keisei Nakamura, Akihiro Yamauchi, Kumiko Ishida, Satoshi Tanaka, Mikito Kawamata, Takayuki Shindo Lymphedema is a chronic condition caused by disruption of lymphatic vessels, which often occurs after invasive surgery. Calcitonin gene–related peptide (CGRP) is a 37-amino acid peptide produced by alternative splicing of the primary transcript of the calcitonin/CGRP gene. CGRP was initially identified as a neuropeptide released primarily from sensory nerves and involved in regulating pathophysiological nociceptive pain. However, recent studies have shown CGRP is also released from a variety of other cells and possesses multiple functions. In this study, CGRP knockout (-/-) mice were used to show the actions of endogenous CGRP in postoperative lymphedema. After generating a mouse postoperative tail lymphedema model, the edema was observed to be more severe in CGRP-/- than wild-type mice. Numbers of LYVE-1–positive lymphatic capillaries were decreased and lymphatic capillary formation–related factors were down-regulated in CGRP-/- mice. In addition, accumulation of M2, but not M1 macrophages was selectively reduced in the edematous tissue of CGRP-/- mice. Selective depletion of M2 macrophages decreased lymphatic capillary formation and worsened lymphedema in wild-type mice but not CGRP-/- mice, where numbers of M2 macrophages were already diminished. These findings suggest that endogenous CGRP acts to ameliorate postoperative lymphedema by enhancing lymphatic capillary formation and M2 macrophages play critical roles. CGRP may be a useful therapeutic target for the treatment of postoperative lymphedema.
  • Spatio-temporal gradient of cortical neuron death contributes to
           microcephaly in knock-in mouse model of ligase 4 syndrome
    • Abstract: Publication date: Available online 18 September 2019Source: The American Journal of PathologyAuthor(s): Melody P. Lun, Morgan L. Shannon, Sevgi Keles, Ismail Reisli, Nicole Luche, Douglas Ryan, Kelly Capuder, Luigi D. Notarangelo, Maria K. Lehtinen Cells of the developing central nervous system are particularly susceptible to formation of double-stranded DNA breaks (DSBs) arising from physiological and/or environmental insults. Therefore, efficient repair of DSBs is especially vital for maintaining cellular health and proper functioning in the developing brain. Here, we demonstrate increased expression of DSB initiating and non-homologous end joining repair machinery in newborn neurons in the developing brains of both mouse and human. In parallel, we provide the first characterization of the brain phenotype in the Lig4R278H/R278H (Lig4R/R) mouse model of DNA Ligase 4 (LIG4) syndrome, in which a hypomorphic Lig4 mutation, originally identified in patients, impedes non-homologous end joining. We show that Lig4R/R mice develop non-progressive microcephaly, resulting primarily from apoptotic death of newborn neurons that is both spatially and temporally specific during peak cortical neurogenesis. This apoptosis leads to a reduction in neurons throughout the postnatal cerebral cortex, but with a more prominent impact on those of the lower cortical layers. Together, our findings begin to uncover the pathogenesis of microcephaly in LIG4 syndrome and open avenues to more focused investigations on the critical roles of DSB formation and repair in vulnerable neuronal populations of the brain.
  • Detection of lung cancer lymph node metastases from whole-slide
           histopathological images using a two-step deep learning approach
    • Abstract: Publication date: Available online 18 September 2019Source: The American Journal of PathologyAuthor(s): Hoa Hoang Ngoc Pham, Mitsuru Futakuchi, Andrey Bychkov, Tomoi Furukawa, Kishio Kuroda, Junya Fukuoka The application of deep learning for the detection of lymph node metastases on histological slides has attracted worldwide attention due to its potentially important role in patient treatment and prognosis. Despite this attention, false positive predictions remain problematic, particularly in the case of reactive lymphoid follicles. In this study, a novel two-step deep learning algorithm was developed to address the issue of false-positive prediction while maintaining accurate cancer detection. Three-hundred and forty-nine whole-slide lung cancer lymph node images, including 233 slides for algorithm training, 10 slides for validation, and 106 slides for evaluation, were collected. In the first step, a deep learning algorithm was used to eliminate frequently misclassified noncancerous regions (lymphoid follicles). In the second step, a deep learning classifier was developed to detect cancer cells. Using this two-step approach, errors were reduced by 36.4% on average and up to 89% in slides with reactive lymphoid follicles. Furthermore, 100% sensitivity was reached in cases of macro-metastases, micro-metastases, and isolated tumor cells. To reduce the small number of remaining false-positives, an ROC curve was created using foci size thresholds of 0.6 mm and 0.7 mm, achieving sensitivity and specificity of 79.6% and 96.5%, and 75.5% and 98.2%, respectively. A two-step approach can be used to detect lung cancer metastases in lymph node tissue effectively and with few false-positives.
  • Serum amyloid P and a DC-SIGN ligand inhibit high fat diet–induced
           adipose tissue and liver inflammation and steatosis in mice
    • Abstract: Publication date: Available online 18 September 2019Source: The American Journal of PathologyAuthor(s): Darrell Pilling, Nehemiah Cox, Megan A. Thomson, Tejas R. Karhadkar, Richard H. Gomer High-fat diet (HFD)-induced inflammation is associated with a variety of health risks. The systemic pentraxin serum amyloid P (SAP) inhibits inflammation. SAP activates the high affinity IgG receptor Fcγ receptor I (FcγRI; CD64) and the lectin receptor DC-SIGN (CD209). Here, we show that for mice on a HFD, injections of SAP and a synthetic CD209 ligand (1866) reduced HFD-increased adipose and liver tissue inflammation, adipocyte differentiation, and lipid accumulation in adipose tissue. HFD worsened glucose tolerance tests and caused increased adipocyte size; for mice on a HFD, SAP improved glucose tolerance tests and reduced adipocyte size. Mice on a HFD had elevated serum levels of interleukin (IL)-1β, IL-23, interferon (IFN)-β, IFN-γ, MCP-1, and tumor necrosis factor-α. SAP reduced serum levels of IL-23, IFN-β, MCP-1, and tumor necrosis factor-α, whereas 1866 reduced IFN-γ. In vitro, SAP, but not 1866, treated cells isolated from white fat tissue (stromal vesicular fraction) produced the anti-inflammatory cytokine IL-10. HFD causes steatosis, and both SAP and 1866 reduced it. Conversely, compared to control mice, SAP knockout mice fed on a normal diet had increased white adipocyte cell sizes, increased numbers of inflammatory cells in adipose and liver tissue, and steatosis, and these effects were exacerbated on a HFD. SAP and 1866 may inhibit some but not all of the effects of a high fat diet.
  • Elevated miR-615-3p expression predicts adverse clinical outcome and
           promotes proliferation and migration of prostate cancer cells
    • Abstract: Publication date: Available online 17 September 2019Source: The American Journal of PathologyAuthor(s): Emma Bollmann Laursen, Jacob Fredsøe, Linnéa Schmidt, Siri Strand, Helle Kristensen, Anne Karin Ildor Rasmussen, Tina Fuglsang Daugaard, Peter Mouritzen, Søren Høyer, Gitte Kristensen, Hein Vincent Stroomberg, Klaus Brasso, Martin Andreas Røder, Michael Borre, Karina Dalsgaard Sørensen miR-615-3p has previously been described as up-regulated in prostate cancer (PC) tissue samples compared with non-malignant controls, however its prognostic potential and functional role in PC remains largely unknown. In this study, we investigated the clinical and biological relevance of miR-615-3p in PC. The expression of miR-615-3p was measured in PC tissue specimens from 239 men who underwent radical prostatectomy (RP) and it was investigated if miR-615-3p could predict post-operative biochemical recurrence (BCR). These findings were subsequently validated in three independent RP cohorts (N=222, N=273, and N=387) and functional overexpression studies conducted in PC cells (PC3M). High miR-615-3p expression was significantly associated with BCR in four independent PC patient cohorts (P < 0.05, log-rank test). In addition, high miR-615-3p expression was a significant predictor of PC-specific survival (CSS) in univariate [HR 3.75, P < 0.001] and multivariate analysis after adjustment for the CAPRA-S nomogram [HR 2.66, P = 0.008] in a merged RP cohort (N=734). Moreover, overexpression of miR-615-3p in PC cells (PC3M) significantly increased cell viability, proliferation, apoptosis, and migration. Together, our results suggest that miR-615-3p is a significant predictor of post-operative BCR and CSS and has oncogenic functions in PC cells.
  • Ascl2-Regulated Follicular Helper T Cells Promote Autoimmunity in a Murine
           Model for Sjögren’s Syndrome
    • Abstract: Publication date: Available online 17 September 2019Source: The American Journal of PathologyAuthor(s): Kunihiro Otsuka, Akiko Yamada, Masako Saito, Aya Ushio, Mami Sato, Satoru Kisoda, Wenhua Shao, Takaaki Tsunematsu, Yasusei Kudo, Rieko Arakaki, Naozumi Ishimaru Follicular helper T (Tfh) cells contribute to various immune responses as well as to the pathogenesis of several immune diseases. However, the precise mechanism underlying the onset or development of autoimmunity via Tfh cells remains unclear. Here, the detailed relationship between autoimmune disease and Tfh cells was analyzed using a murine model for Sjögren’s syndrome (SS) wherein the mice underwent neonatal thymectomy. Germinal center (GC) development was promoted in this SS model along with an increase of Tfh cells and GC B cells. The severity of the autoimmune lesions was correlated with the number of Tfh cells detected in the spleen of the SS model mice. In addition, treatment with an anti-CD20 monoclonal antibody effectively suppressed the autoimmune lesions with a reduction of Tfh cells and GC B cells. Comprehensive gene analysis revealed that several genes associated with Tfh cell differentiation, including achaete-scute homologue 2 (Ascl2), were up-regulated in peripheral CD25− CD4+ T cells in SS model mice compared to those in control mice. Moreover, an experiment using CD4Cre Bcl6fl/fl mice that received neonatal thymectomy treatment demonstrated that Ascl2 contributes to the Tfh cell differentiation associated with autoimmunity during the early stages independent of Bcl6. In conclusion, our results indicate that abnormal Tfh cell differentiation via Ascl2 regulation might contribute to the pathogenesis of autoimmunity.
  • Klotho deficiency induces arteriolar hyalinosis in a trade-off with
           vascular calcification
    • Abstract: Publication date: Available online 17 September 2019Source: The American Journal of PathologyAuthor(s): Rik Mencke, Anja T. Umbach, Lucas M. Wiggenhauser, Jakob Voelkl, Hannes Olauson, Geert Harms, Marian Bulthuis, Guido Krenning, Leticia Quintanilla-Martinez, Harry van Goor, Florian Lang, Jan-Luuk Hillebrands Hyalinosis is a vascular lesion affecting the renal vasculature and contributing to ageing-related renal function decline. We assessed whether arteriolar hyalinosis is caused by Klotho deficiency – a state known to induce both renal and vascular phenotypes associated with ageing. Histochemistry was used to assess hyalinosis in Klotho-/- kidneys, compared to Klotho+/- and wild-type littermates. Immunohistochemistry was used to investigate vascular lesion composition and the different layers of the vascular wall. Finally, spironolactone was used to inhibit calcification in kl/kl mice and vascular lesions were characterized in the kidney. Arteriolar hyalinosis was detected in Klotho-/- mice, which was present up to the afferent arterioles. Hyalinosis was accompanied by loss of α-smooth muscle actin expression, while the endothelial lining was mostly intact. Hyalinous lesions were positive for IgM and iC3b/c/d, indicating subendothelial leakage of plasma proteins. The presence of extracellular matrix proteins suggested increased production by smooth muscle cells. Finally, in Klotho-/- mice with marked vascular calcification, treatment with spironolactone allowed for replacement of calcification by hyalinosis. Klotho deficiency potentiates both endothelial hyperpermeability and smooth muscle cell de-differentiation. Absent a calcification-inducing stimulus, smooth muscle cells assume a synthetic phenotype in response to subendothelial leakage of plasma proteins. In the kidney, this results in arteriolar hyalinosis, which contributes to the decline in renal function. Klotho may play a role in preventing ageing-related arteriolar hyalinosis.
  • Transforming growth factor-β receptor internationalization via caveolae
           is regulated by tubulin-β2 and tubulin-β3 during endothelial-mesenchymal
    • Abstract: Publication date: Available online 17 September 2019Source: The American Journal of PathologyAuthor(s): Katarzyna Sobierajska, Marta Ewelina Wawro, Wojciech Michał Ciszewski, Jolanta Niewiarowska Fibrotic disorders, which are caused by long-term inflammation, are observed in numerous organs. These disorders are regulated mainly through transforming growth factor (TGF)-β family proteins by a fundamental cellular mechanism, known as the endothelial-mesenchymal transition. Therefore, there is a pressing need to identify the mechanisms and potential therapeutic targets that enable the inhibition of endothelial transdifferentiation. This study is the first to demonstrate that glycosylation of tubulin-β2 (TUBB2) and tubulin-β3 (TUBB3) in microtubules enhances sensitivity to TGF-β1 stimulation in human microvascular endothelial cells. We observed that the microtubules enriched in glycosylated TUBB2 and TUBB3 were necessary for caveolae-dependent TGF-β receptor internalization. Posttranslational modulation is critical for the generation of myofibroblasts through endothelial-mesenchymal transition during fibrosis development. We suggest that microtubule glycosylation may become the target of new effective therapies for patients with recognized fibrotic diseases.
  • RelB regulates lymphatic endothelial cells during vessel maturation and is
           required for lymphatic vessel function in adult mice
    • Abstract: Publication date: Available online 17 September 2019Source: The American Journal of PathologyAuthor(s): Qianqian Liang, Li Zhang, Ronald W. Wood, Rui-Cheng Ji, Brendan F. Boyce, Edward.M. Schwarz, Yongjun Wang, Lianping Xing NF-κB signals through canonical RelA/p50 and noncanonical RelB/p52 pathways. The RelA/p50 is involved in basal and inflammatory lymphangiogenesis. However, the role of RelB/p52 in lymphatic vessel biology is unknown. Here, we investigated changes in lymphatic vessels (LVs) in mice deficient in noncanonical NF-κB signaling, and the function of RelB in lymphatic endothelial cells (LECs). LVs were examined in Relb-/-, p52-/-, or control mice, and the gene expression profiles in LECs with RelB knockdown. Relb-/-, but not p52-/- mice, exhibited multiple LV abnormalities. They include i) increased capillary vessel diameter, ii) reduced smooth muscle cell (SMC) coverage of mature vessels, iii) leakage, and iv) loss of active and passive lymphatic flow. Relb-/- mature LVs had thinner vessel walls, more apoptotic LECs and SMCs, and fewer LEC junctions. RelB knockdown LECs had decreased growth, survival, adhesion, and dysregulated signaling pathways involving these cellular events. These results suggest that Relb-/- mice have abnormal LVs, mainly in mature vessels with reduced SMC coverage, leakage, and loss of contractions. RelB knockdown in LECs leads to reduced growth, survival, and adhesion. RelB plays a vital role in LEC-mediated LV maturation and function.
  • Effects of High Glucose–Induced Lysyl Oxidase Propeptide on Retinal
           Endothelial Cell Survival: Implications for Diabetic Retinopathy
    • Abstract: Publication date: Available online 16 September 2019Source: The American Journal of PathologyAuthor(s): Dongjoon Kim, Dayeun Lee, Philip C. Trackman, Sayon RoyDiabetic retinopathy (DR) is characterized by apoptotic cell loss in the retinal vasculature. Lysyl oxidase propeptide (LOX-PP), released during LOX processing, has been implicated in promoting apoptosis in various diseased tissues. However, its role in the development and progression of DR is unknown. We investigated whether high glucose (HG) or diabetes alters LOX-PP expression and thereby influences AKT pathway and affects retinal endothelial cell survival. Rat retinal endothelial cells were grown in normal medium, normal medium and exposed to recombinant LOX-PP (rLOX-PP) or HG medium and examined for LOX-PP expression, AKT and caspase-3 activation. Similarly, rats intravitreally injected with rLOX-PP were examined for changes in retinal LOX-PP levels, AKT phosphorylation, and the number of acellular capillaries and pericyte loss compared with those of control diabetic and nondiabetic rats. Results indicate that HG up-regulates LOX-PP expression and reduces AKT activation. In addition, cells exposed to rLOX-PP alone exhibited increased apoptosis concomitant with decreased AKT phosphorylation. In retinas of diabetic rats, increased LOX-PP level, decreased AKT phosphorylation, and increased number of acellular capillaries and pericyte loss compared with those of nondiabetic rats were observed. Of interest, similar changes were noted in the retinas of rats injected with rLOX-PP. Findings from this study suggest that hyperglycemia-induced LOX-PP overexpression may contribute to retinal vascular cell loss associated with DR.
  • Bioactive lipids in shoulder tendon tears
    • Abstract: Publication date: Available online 14 September 2019Source: The American Journal of PathologyAuthor(s): Undurti N. Das
  • This Month in AJP
    • Abstract: Publication date: Available online 13 September 2019Source: The American Journal of PathologyAuthor(s): Chhavi Chauhan
  • Lactoferrin CpG Island Hypermethylation and Decoupling of mRNA and Protein
           Expression in the Early Stages of Prostate Carcinogenesis
    • Abstract: Publication date: Available online 6 September 2019Source: The American Journal of PathologyAuthor(s): Corey M. Porter, Michael C. Haffner, Ibrahim Kulac, Janielle P. Maynard, Javier A. Baena-Del Valle, William B. Isaacs, Srinivasan Yegnasubramanian, Angelo M. De Marzo, Karen S. Sfanos Lactoferrin (LTF) is an iron binding protein canonically known for its innate and adaptive immune functions. LTF may also act as a tumor suppressor with anti-proliferative action. LTF is inactivated genetically or epigenetically in various cancers, and a CpG island spanning the transcriptional start site of LTF is hypermethylated in prostate cancer cell lines. We therefore hypothesized that LTF expression is silenced via CpG island hypermethylation in the early stages of prostate tumorigenesis. Targeted methylation analysis was performed using a combination of methylated-DNA precipitation and methylation-sensitive restriction enzymes and laser capture microdissection followed by bisulfite sequencing on DNA isolated from prostate tissue samples including both primary and metastatic disease. LTF mRNA in situ hybridization and LTF protein immunohistochemistry was also performed. We report that the LTF CpG island is frequently and densely methylated in high grade prostatic intraepithelial neoplasia, primary prostate carcinoma, and metastases. We further report a decoupling of lactoferrin mRNA and protein expression, including in lesions where LTF mRNA has presumably been silenced via CpG island methylation. We conclude that LTF mRNA expression is silenced in prostate tumorigenesis via hypermethylation, supporting a role for LTF as a prostate cancer tumor suppressor gene. Likewise, the frequency at which the LTF CpG island is methylated across samples suggests it is an important and conserved step in prostate cancer initiation.
  • The role of MET in melanoma and melanocytic lesions
    • Abstract: Publication date: Available online 30 August 2019Source: The American Journal of PathologyAuthor(s): Yan Zhou, Kyu Young Song, Alessio Giubellino Melanoma is the leading cause of death due to cutaneous malignancy and its incidence is on the rise. Several signaling pathways have been recognized to have an etiopathogenetic role in precursor melanocytic lesions and malignant melanoma development and progression, including receptor tyrosine kinases. Among those, MET/HGF axis is emerging as a critical player not only in the tumor itself but also in the immune microenvironment in which the tumor grows and advance in its development. Moreover, this pathway’s activation has emerged as a paradigm of tumor resistance to modern targeted therapies and assessment of its expression in patients’ sample may be a valuable biomarker of tumor progression and response to targeted therapy.Here we summarize our current understanding of this important receptor tyrosine kinase in normal melanocyte proliferation/motility, tumor progression and metastasis, its genetic alterations in certain subtype of melanocytic lesions and how its pathway has been explored for the development of selective inhibitors.
  • Smooth Muscle α-actin Deficiency Leads to Decreased Liver Fibrosis via
           Impaired Cytoskeletal Signaling in Hepatic Stellate Cells
    • Abstract: Publication date: Available online 30 August 2019Source: The American Journal of PathologyAuthor(s): Don C. Rockey, Qinghong Du, Zengdun ShiIn the liver, smooth muscle α-actin (SM α-actin) is up-regulated in hepatic stellate cells (HSCs) as they transition to myofibroblasts during liver injury and the wound healing response. Whether SM α-actin has specific functional effects on cellular effectors of fibrosis such as HSC is controversial. Here, we focused on the relationship between SM α-actin and type 1 collagen expression (COL1A1), a major extracellular matrix protein important in liver fibrosis and demonstrate that knockout of SM α-actin leads to reduced liver fibrosis and COL1 expression. The mechanism for the reduction in fibrogenesis in vivo is multifactorial, including not only a reduction in the number of HSCs, but also HSC specific reduction in COL1 expression in Acta2 deficient HSCs. Despite a compensatory increase in expression of cytoplasmic β-actin and γ-actin isoforms in Acta2-/- HSCs, defects were identified in each transforming growth factor beta/Smad2/3 and ET-1/Erk1/2 signaling in Acta2-/- HSCs. These data not only suggest a molecular link between the SM α-actin cytoskeleton and classic fibrogenic signaling cascades, but also emphasize the relationship between SM α-actin and fibrogenesis in hepatic myofibroblasts in vivo.
  • Down-Regulation of Circular RNA_000926 Attenuates Renal Cell Carcinoma
           Progression through microRNA-411-Dependent CDH2 Inhibition
    • Abstract: Publication date: Available online 30 August 2019Source: The American Journal of PathologyAuthor(s): Dong Zhang, Xiao-Jie Yang, Qi-Dong Luo, De-Lai Fu, Zhao-Lun Li, Peng Zhang, Tie Chong Accumulating studies have recognized that circular RNAs (circRNAs) can be promising targets for renal cell carcinoma (RCC) by acting as ceRNAs for microRNAs (miRNAs). This study intends to uncover the implication of a novel circRNA circ_000926 in RCC, and how it affects tumorigenesis. Microarray-based circRNA/gene expression profiling of RCC was employed to identify differentially expressed circRNAs/genes in RCC and normal tissues. miRNAs targeting the screened circRNAs/genes were predicted online, followed by analyzing circ_000926 expression in RCC. The crosstalk among circ_000926, miR-411, and CDH2 was then validated. The expression of circ_000926, miR-411, and CDH2 was up-regulated or down-regulated in RCC cells to unearth their effects on the biological behaviors of RCC cells. circ_000926 was found to be highly expressed in RCC tissues and cell lines, whereby CDH2 was verified to be a target of miR-411. As a ceRNA, circ_000926 could directly bind to miR-411 to up-regulate CDH2. Down-regulation of circ_000926 resulted in inhibited growth, migration, and invasion abilities of RCC cells, as well as suppressed EMT and tumor growth. However, the inhibition of miR-411 or elevation of CDH2 reversed the anti-tumor effects induced by silencing circ_000926. Altogether, down-regulation of circ_000926 exerts an inhibitory effect on RCC progression through miR-411–dependent CDH2 inhibition, highlighting a potential target for RCC treatment.
  • Neutrophil-derived reactive oxygen orchestrates epithelial cell signaling
           events during intestinal repair
    • Abstract: Publication date: Available online 28 August 2019Source: The American Journal of PathologyAuthor(s): Jason D. Matthews, Joshua A. Owens, Crystal R. Naudin, Bejan J. Saeedi, Ashfaqul Alam, April R. Reedy, Benjamin H. Hinrichs, Ronen Sumagin, Andrew S. Neish, Rheinallt M. Jones Recent evidence has demonstrated that reactive oxygen, eg, hydrogen peroxide, can activate host cell signaling pathways that function in repair. We show that mice deficient in their capacity to generate reactive oxygen by the Nox2 holoenzyme, an enzyme complex highly expressed in neutrophils and macrophages, have disrupted capacity to orchestrate signaling events that function in mucosal repair. Similar observations were made for mice after neutrophil depletion, pinpointing this cell type as the source of the reactive oxygen driving redox protein signaling in the epithelium. To simulate epithelial exposure to high levels of reactive oxygen produced by neutrophils and gain new insight into this redox signaling, epithelial cells were treated with H2O2 and biochemical experiments conducted and a proteome-wide screen performed using isotope-coded affinity tags to detect proteins oxidized following exposure. This analysis implicated signaling pathways regulating focal adhesions, cell junctions, and maintenance of the cytoskeleton. These pathways are also known to act via coordinated phosphorylation events within proteins that constitute the focal adhesion complex, including focal adhesion kinase and Crk-associated substrate. We identified the Rho family small GTP–binding protein Rac1 and p21 activated kinases 2 as operational in these signaling and localization pathways. These data support the hypothesis that reactive oxygen species from neutrophils can orchestrate epithelial cell–signaling events functioning in intestinal repair.
  • Tissue iron promotes wound repair via M2 macrophage polarisation and the
           chemokines CCL17 and CCL22
    • Abstract: Publication date: Available online 27 August 2019Source: The American Journal of PathologyAuthor(s): Holly Nicola Wilkinson, Elizabeth Rose Roberts, Amber Rose Stafford, Kayleigh Louise Banyard, Paolo Matteucci, Kimberly Ann Mace, Matthew James Hardman Macrophages are important for effective iron recycling and erythropoiesis, but also play a crucial role in wound healing, orchestrating tissue repair. Recently, we demonstrated a significant accumulation of iron in healing wounds, and a requirement of iron for effective repair. Here, we sought to determine the influence of iron on macrophage function in the context of wound healing. Interestingly, wound macrophages extensively sequestered iron throughout healing, associated with a pro-healing M2 phenotype. In delayed healing diabetic mouse wounds, both macrophage polarisation and iron sequestration were impaired. In vitro studies revealed that iron promotes differentiation, while skewing macrophages towards a hypersecretory M2-like polarisation state. These macrophages produced high levels of CCL17 and CCL22, promoting wound re-epithelialization and extracellular matrix deposition in a human ex vivo wound healing model. Together, these findings reveal a novel, unappreciated role for iron in modulating macrophage behavior to promote subsequent wound repair. These findings support therapeutic evaluation of iron use to promote wound healing in the clinic.
  • Repression of death receptor–mediated apoptosis of hepatocytes by
           Hepatitis B virus e antigen
    • Abstract: Publication date: Available online 23 August 2019Source: The American Journal of PathologyAuthor(s): Wei Liu, Teng-Fei Guo, Zhen-Tang Jing, Qiao-Yun Tong Hepatitis B virus (HBV) e antigen (HBeAg) is considered to associate with viral persistence and pathogenesis. Resistance of HBV-infected hepatocytes to apoptosis is seen as one of the primary promotors for HBV chronicity and malignancy. Fas receptor/ligand (Fas/FasL) and tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) system plays a key role in hepatic death during HBV infection. We find here that HBeAg mediates resistance of hepatocytes to FasL or TRAIL-induced apoptosis. Introduction of HBeAg into human hepatocytes rendered resistance to FasL or TRAIL cytotoxicity in a p53-dependent manner. HBeAg further inhibited the expression of p53, total Fas, membrane-bound Fas, TNF receptor superfamily member 10a (DR4), and TNF receptor superfamily member 10b (DR5) at both mRNA and protein levels. In contrast, HBeAg enhanced the expression of soluble forms of Fas through facilitation of Fas alternative mRNA splicing. In a mouse model, expression of HBeAg in mice injected with recombinant adenovirus–associated virus 8 inhibited agonistic anti-Fas antibody (Jo2)-induced hepatic apoptosis. Xenograft tumorigenicity assay also showed that HBeAg-induced carcinogenesis was resistant to the pro-apoptotic effect of TRAIL and chemotherapeutic drugs. These results indicate that HBeAg may prevent hepatocytes from FasL and TRAIL-induced apoptosis by regulating the expression of pro-apoptotic and anti-apoptotic form of death receptors, which may contribute to the survival and persistence of infected hepatocytes during HBV infection.
  • Vitamin D and calcium supplementation accelerates Randall’s plaque
           formation in a murine model
    • Abstract: Publication date: Available online 23 August 2019Source: The American Journal of PathologyAuthor(s): Elise Bouderlique, Ellie Tang, Joëlle Perez, Amélie Coudert, Dominique Bazin, Marie-Christine Verpont, Christophe Duranton, Isabelle Rubera, Jean-Philippe Haymann, Georges Leftheriotis, Ludovic Martin, Michel Daudon, Emmanuel Letavernier Most of kidney stones are made of calcium oxalate crystals. Randall’s plaque, an apatite deposit at the tip of the renal papilla is considered to be at the origin of these stones. Hypercalciuria may promote Randall’s plaque formation and growth. We analyzed whether long-term exposure of Abcc6-/- mice (a murine model of Randall’s plaque) to vitamin D supplementation, with or without calcium-rich diet, would accelerate the formation of Randall’s plaque. Eight groups of mice (including Abcc6-/- and wild-type) received vitamin D alone (100,000 UI/Kg every 2 weeks), a calcium-enriched diet alone (calcium gluconate 2g/l in drinking water), both vitamin D supplementation and calcium rich diet, or a standard diet (controls) for 6 months. Kidney calcifications were assessed by 3D-micro-computed tomography, μ-Fourier transform infrared spectroscopy, field emission-scanning electron microscopy, transmission electron microscopy, and Yasue staining. At 6 months, Abcc6-/- mice exposed to vitamin D and calcium supplementation developed massive Randall’s plaque when compared to control Abcc6-/- mice (P < 0.01). Wild-type animals did not develop significant calcifications when exposed to vitamin D. Combined administration of vitamin D and calcium accelerates significantly Randall’s plaque formation in a murine model. This original model raises concerns about the cumulative risk of vitamin D supplementation and calcium intakes in Randall’s plaque formation.
  • Identification of Metabolic Changes in Ileum, Jejunum, Skeletal Muscle,
           Liver, and Lung in a Continuous I.V. Pseudomonas aeruginosa Model of
           Sepsis Using Nontargeted Metabolomics Analysis
    • Abstract: Publication date: September 2019Source: The American Journal of Pathology, Volume 189, Issue 9Author(s): Amro Ilaiwy, Gabriella A.M. ten Have, James R. Bain, Michael J. Muehlbauer, Sara K. O'Neal, Jessica M. Berthiaume, Traci L. Parry, Nicolaas E. Deutz, Monte S. WillisSepsis is a multiorgan disease affecting the ileum and jejunum (small intestine), liver, skeletal muscle, and lung clinically. The specific metabolic changes in the ileum, jejunum, liver, skeletal muscle, and lung have not previously been investigated. Live Pseudomonas aeruginosa, isolated from a patient, was given via i.v. catheter to pigs to induce severe sepsis. Eighteen hours later, ileum, jejunum, medial gastrocnemius skeletal muscle, liver, and lung were analyzed by nontargeted metabolomics analysis using gas chromatography/mass spectrometry. The ileum and the liver demonstrated significant changes in metabolites involved in linoleic acid metabolism: the ileum and lung had significant changes in the metabolism of valine/leucine/isoleucine; the jejunum, skeletal muscle, and liver had significant changes in arginine/proline metabolism; and the skeletal muscle and lung had significant changes in aminoacyl-tRNA biosynthesis, as analyzed by pathway analysis. Pathway analysis also identified changes in metabolic pathways unique for different tissues, including changes in the citric acid cycle (jejunum), β-alanine metabolism (skeletal muscle), and purine metabolism (liver). These findings demonstrate both overlapping metabolic pathways affected in different tissues and those that are unique to others and provide insight into the metabolic changes in sepsis leading to organ dysfunction. This may allow therapeutic interventions that focus on multiple tissues or single tissues once the relationship of the altered metabolites/metabolism to the underlying pathogenesis of sepsis is determined.
  • This Month in AJP
    • Abstract: Publication date: Available online 21 August 2019Source: The American Journal of PathologyAuthor(s):
  • A new role for the spleen: aggravation of the systemic inflammatory
           response in rats with severe acute pancreatitis
    • Abstract: Publication date: Available online 17 August 2019Source: The American Journal of PathologyAuthor(s): Rui Zhou, Jian Zhang, Wangjun Bu, Wei Zhang, Baojun Duan, Xianwei Wang, Libo Yao, Zongfang Li, Jun Li Little is known about the role of the spleen in mediating systemic inflammatory responses in severe acute pancreatitis (SAP). Here, we investigated the role played by the spleen in rats after SAP induction. Splenectomy was performed at designated time points after SAP induction. Pancreatic tissue and serum samples were collected and subjected to histological, immunohistochemical, and immunological analyses. Following SAP induction, the splenic immune response was enhanced during SAP progression, as shown by the increased diameter of the splenic periarterial lymphatic sheath and the thickness of the splenic marginal zone. Rats with splenectomy developed acute pancreatitis more slowly than rats without splenectomy. Additionally, pancreatic tissues of rats with splenectomy contained lower levels of serum amylase, tumor necrosis factor-α, and interleukin-6 and exhibited less acinar cell death, leucocyte infiltration, and interstitial oedema than those of rats without splenectomy. Compared with splenectomy alone, cotreatment with splenectomy and the administration of splenic cells originating from a rat with SAP 12 h after induction increased systemic inflammation in SAP rats. Splenic factors exacerbated SAP-associated liver and lung injury and accentuated intestinal mucosal barrier dysfunction. Splenectomy altered the serum cytokine profile in rats with SAP. In a rat model of SAP, the spleen exacerbated the systematic inflammatory responses and injury to multiple organs, indicating a new role for the spleen in SAP.
  • The Inability of the Choroid to Revascularize in Oxygen-Induced
           Retinopathy Results from Increased P53/mir-Let-7b Activity
    • Abstract: Publication date: Available online 17 August 2019Source: The American Journal of PathologyAuthor(s): Tianwei Ellen Zhou, Tang Zhu, José Carlos Rivera, Samy Omri, Houda Tahiri, Isabelle Lahaie, Raphaël Rouget, Maëlle Wirth, Stanley Nattel, Gregory Lodygensky, Gerardo Ferbeyre, Mohammad Nezhady, Michel Desjarlais, Patrick Hamel, Sylvain ChemtobRetinopathy of prematurity (ROP) is characterized by an initial retinal avascularisation, followed by pathologic neovascularization. Recently, choroidal thinning has also been detected in children formerly diagnosed with ROP; a similar sustained choroidal thinning is observed in ROP models. But the mechanism underlying the lack of choroidal revascularization remains unclear, and was investigated in an oxygen-induced retinopathy (OIR) model. In OIR, evidence of senescence was detected, preceded by oxidative stress in the choroid and the retinal pigment epithelium. This was associated with a global reduction of pro-angiogenic factors, including insulin-like growth factor 1 receptor (Igf1R). Coincidentally, tumor suppressor p53 was highly expressed in the OIR retinae. Curtailing p53 activity resulted in reversal of senescence, normalization of Igf1r expression, and preservation of choroidal integrity. OIR-induced down-regulation of Igf1r was mediated at least partly by microRNA (miRNA) let-7b as i) let-7b expression was augmented throughout and beyond the period of oxygen exposure, ii) let-7b directly targeted Igf1r mRNA, and iii) p53 knock-down blunted let-7b expression, restored Igf1r expression, and elicited choroidal revascularization. Finally, restoration of Igf1r expression rescued choroid thickness. Altogether, this study uncovers a significant mechanism for defective choroidal revascularization in OIR, revealing a new role for p53/let-7b/IGF-1R axis in the retina. Future investigations on this (and connected) pathway could further our understanding of other degenerative choroidopathies, such as geographic atrophy.
  • N-acetylcysteine resolves placental inflammatory-vasculopathic changes in
           mice consuming a high fat diet
    • Abstract: Publication date: Available online 17 August 2019Source: The American Journal of PathologyAuthor(s): Lyda Williams, Emmanuel S. Burgos, Patricia M. Vuguin, Clarence R. Manuel, Ryan Pekson, Swapna Munnangi, Sandra E. Reznik, Maureen J. Charron The mechanism by which poor maternal nutrition can impact the long-term health of offspring is poorly understood. In mice, we previously demonstrated maternal high fat diet (HFD) exposure results in reduced fetal growth regardless of maternal genotype. Here, we test our hypothesis that maternal HFD-induced inflammation contributes to metabolic disease susceptibility of the offspring via alterations in the placenta. The effect of maternal genotype, diet, and treatment with the anti-inflammatory compound N-acetylcysteine (NAC) on placental morphology was investigated. Placentas from wild type (WT) dams maintained on a HFD, but not those heterozygous (+/-) for Glut4 (Slc2a4) on the same diet, demonstrated an increase in decidual inflammation and vasculopathy occurring together. NAC administration resulted in amelioration of HFD-induced decidual vasculopathy independent of offspring genotype and sex. Consistent with these morphologic improvements, placentas from HFD dams treated with NAC demonstrated decreased mRNA and immunostaining of interleukin-1β and MCP1, decreased mRNA of inflammatory genes, and increased mRNA of Vegfa. These results strongly suggest consumption of a HFD results in vascular changes in placenta reflected by alterations in expression of pivotal vascular developmental markers and inflammatory genes all of which are ameliorated by NAC. These placental changes play a key role in the increased programmed metabolic disease of HFD-exposed offspring.
  • Myeloid-Derived Lymphatic Endothelial Cell Progenitors Significantly
           Contribute to Lymphatic Metastasis in Clinical Breast Cancer
    • Abstract: Publication date: Available online 15 August 2019Source: The American Journal of PathologyAuthor(s): Lisa Volk-Draper, Radhika Patel, Nihit Bhattarai, Jie Yang, Andrew Wilber, David DeNardo, Sophia RanLymphatic metastasis is a high impact prognostic factor for mortality of breast cancer (BC) patients, and directly depends on tumor-associated lymphatic vessels. We previously reported that lipopolysaccharide-induced inflammatory lymphangiogenesis is strongly promoted by myeloid-derived lymphatic endothelial cell progenitors (M-LECP) derived from the bone marrow (BM). As BC recruit massive numbers of pro-vascular myeloid cells, we hypothesized that M-LECP, within this recruited population, are specifically programmed to promote tumor lymphatics that increase lymph node metastasis. In support of this hypothesis, high levels of M-LECP were found in peripheral blood and tumor tissues of BC patients. Moreover, the density of M-LECP and lymphatic vessels positive for myeloid marker proteins strongly correlated with patient node status. It was also established that tumor M-LECP co-express lymphatic-specific, stem/progenitor and M2-type macrophage markers that indicate their BM hematopoietic-myeloid origin and distinguish them from mature lymphatic endothelial cells, tumor-infiltrating lymphoid cells, and tissue-resident macrophages. Using four orthotopic BC models, we show that mouse M-LECP are similarly recruited to tumors and integrate into pre-existing lymphatics. Finally, we demonstrate that adoptive transfer of in vitro differentiated M-LECP, but not naïve or non-differentiated BM cells, significantly increased metastatic burden in ipsilateral lymph nodes. These data support a causative role of BC-induced lymphatic progenitors in tumor lymphangiogenesis and suggest molecular targets for their inhibition.
  • Prostate Cancer- The Role of Inflammation and Chemokines
    • Abstract: Publication date: Available online 14 August 2019Source: The American Journal of PathologyAuthor(s): Aradhana Rani, Prokar Dasgupta, John J. MurphyProstate cancer (PC) is a leading cause of death in men. Inflammation is one of the initiating processes whereby cells are trafficked into the tumor microenvironment by specific cytokines termed chemokines. This recruitment is complex and involves diverse leucocyte subsets with pro-cancer and anti-cancer functions. Chemokines promote/abrogate proliferation of cancerous cells, block/aid apoptosis and are instrumental/detrimental in cancer cell migration required for metastasis. Chemokines guide the release/transport of immune cells that serve as chaperones at sites of inflammation and following subsequent activation, lead to an immune response. The variety of immune cells recruited at the site of tumor initiation possess unique functions and the plethora of chemokines released by each cell derived from a progenitor cell activated under a defined set of conditions dictates its specific role in cancer progression/regression. Geographic consequences that govern the climate and endemic diseases along with the associated evolutionary effects which at times protect populations from one disease could lead to genetic variations that determine a role for ethnicity and race in PC risk and susceptibility. Dysregulated expression or an imbalance in the homeostatic mechanisms associated with chemokines is implicated in PC. This review discusses the role of inflammation and chemokines in PC.
  • The serotype-specific role of RocA polymorphisms in the pathogenesis of
           invasive group A streptococcal infections
    • Abstract: Publication date: Available online 14 August 2019Source: The American Journal of PathologyAuthor(s): Stephan Brouwer, Mark J. Walker
  • KH-Type Splicing Regulatory Protein Controls Colorectal Cancer Cell Growth
           and Modulates the Tumor Microenvironment
    • Abstract: Publication date: Available online 9 August 2019Source: The American Journal of PathologyAuthor(s): Francesco Caiazza, Katarzyna Oficjalska, Miriam Tosetto, James J. Phelan, Sinéad Noonan, Petra Martin, Kate Killick, Laura Breen, Fiona O’Neill, Blathnaid Nolan, Simon Furney, Robert Power, David Fennelly, Charles S. Craik, Jacintha O’Sullivan, Kieran Sheahan, Glen A. Doherty, Elizabeth J. RyanKH-type splicing regulatory protein (KHSRP) is a multifunctional nucleic acid binding protein implicated in key aspects of cancer cell biology: inflammation and cell-fate determination. However, the role KHSRP plays in colorectal cancer (CRC) tumorigenesis remains largely unknown. Using a combination of in silico analysis of large datasets, ex vivo analysis of protein expression in patients, and mechanistic studies using in vitro models of CRC, we investigated the oncogenic role of KHSRP. We demonstrated KHSRP expression in the epithelial and stromal compartments of both primary and metastatic tumors. Elevated expression was found in tumor versus matched normal tissue, and these findings were validated in larger independent cohorts in silico. KHSRP expression was a prognostic indicator of worse overall survival (HR=3.74, 95% CI = 1.43 to 22.97, P = 0.0138). Mechanistic data in CRC cell line models supported a role of KHSRP in driving epithelial cell proliferation in both a primary and metastatic setting, through control of the G1/S transition. Additionally, KHSRP promoted a pro-angiogenic extracellular environment by regulating the secretion of oncogenic proteins involved in diverse cellular processes such as migration and response to cellular stress. Our study provides novel mechanistic insight into the tumor-promoting effects of KHSRP in CRC.
  • Localization and regulation of polymeric immunoglobulin receptor (PIgR) in
           healthy and diseased human kidney
    • Abstract: Publication date: Available online 9 August 2019Source: The American Journal of PathologyAuthor(s): Krzysztof M. Krawczyk, Helén Nilsson, Jenny Nyström, David Lindgren, Karin Leandersson, Karl Swärd, Martin E. Johansson The polymeric immunoglobulin receptor (PIgR) constitutes an important part of the immune system by mediating transcytosis of dimeric IgA into mucosal fluids. Although well studied in organs such as the intestine, the regulation and localization of PIgR in human kidney are incompletely characterized. Here, using immunohistochemistry we show that in healthy human kidneys, PIgR is expressed by the progenitor-like tubular scattered cells of the proximal tubules and by parietal epithelial cells of glomeruli. We further show that proximal tubular expression of PIgR becomes widespread during kidney disease, correlating to elevated levels of urinary secretory IgA as determined by ELISA. Urinary secretory IgA levels also correlated to the degree of tubular fibrosis, plasma creatinine, and urea levels. In addition, primary tubular cells were cultured to study the function and regulation of PIgR in vitro. Cellular PIgR expression was induced by conditioned medium from activated human leukocytes, as well as by inflammatory cytokines, whereas transforming growth factor-β1 caused decreased expression. Furthermore, IFNγ increased the transcytosis of dimeric IgA in cultured tubular cells. Finally, a correlation study of mRNA data from the Genotype-Tissue Expression portal indicated that PIGR mRNA expression in kidney correlates to the expression of TNFSF13, a cytokine involved in plasma cell class switching to IgA. These results indicate that PIgR induction is an integral part of the injury phenotype of renal tubular cells.
  • Dichotomous Role of Plasmin in Regulation of Macrophage Function after
           Acetaminophen Overdose
    • Abstract: Publication date: Available online 2 August 2019Source: The American Journal of PathologyAuthor(s): Katherine Roth, Jenna Strickland, Nikita Joshi, Meihong Deng, Rebekah Kennedy, Cheryl E. Rockwell, James P. Luyendyk, Timothy R. Billiar, Bryan L. Copple Kupffer cells and monocyte-derived macrophages are critical for liver repair after acetaminophen (APAP) overdose. These cells produce pro-mitogenic cytokines and growth factors, and phagocytose dead cell debris, a process that is critical for resolution of inflammation. The factors that regulate these dynamic functions of macrophages after APAP overdose, however, are not fully understood. We tested the hypothesis that the fibrinolytic enzyme, plasmin, is a key regulator of macrophage function after APAP-induced liver injury. In these studies, inhibition of plasmin in mice with tranexamic acid delayed up-regulation of proinflammatory cytokines after APAP overdose. In culture, plasmin directly, and in synergy with high-mobility group B1, stimulated Kupffer cells and bone-marrow–derived macrophages to produce cytokines by a mechanism that required NF-κB. Inhibition of plasmin in vivo also prevented trafficking of monocyte-derived macrophages into necrotic lesions after APAP overdose. This prevented phagocytic removal of dead cells, prevented maturation of monocyte-derived macrophages into F4/80-expressing macrophages, and prevented termination of proinflammatory cytokine production. Our studies reveal further that phagocytosis is an important stimulus for cessation of pro-inflammatory cytokine production as treatment of proinflammatory, monocyte-derived macrophages, isolated from APAP-treated mice, with necrotic hepatocytes decreased expression of pro-inflammatory cytokines. Collectively, these studies demonstrate that plasmin is an important regulator of macrophage function after APAP overdose.
  • Tumor-promoting activity of long non-coding RNA LINC00466 in lung
           adenocarcinoma via microRNA-144–regulated HOXA10 axis
    • Abstract: Publication date: Available online 2 August 2019Source: The American Journal of PathologyAuthor(s): Tiangang Ma, Yanbing Hu, Yingxue Guo, Bingdi Yan Previous investigations have implicated long non-coding RNAs (lncRNAs) in lung adenocarcinoma, which is an aggressive disease with poor prognosis and high mortality. Through the alteration of lung adenocarcinoma–related lncRNA and microRNA (miRNA) based on microarray analysis, our aim was to understand that the role of LINC00466 and miR-144 in lung adenocarcinoma progression. The relationship among LINC00466, miR-144, and HOXA10 was also verified. Moreover, to examine whether the LINC00466/miR-144/HOXA10 axis contributed to the cellular processes in lung adenocarcinoma, A549 and XWLC-05 cells were transduced with siRNA (si)-LINC00466, si-HOXA10, or miR-144 mimic plasmids. Highly expressed LINC00466 and HOXA10 and lowly expressed miR-144 were eventually revealed in lung adenocarcinoma tissues. HOXA10 was down-regulated in response to the overexpression of miR-144, whereas inhibition of LINC00466 decreased its binding to miR-144, thereby up-regulating miR-144, which in turn halted the lung adenocarcinoma progression. LINC00466 silencing or miR-144 up-regulation exerted an inhibitory role in the tumorigenicity, invasion, migration, and proliferation, and also promoted apoptosis of lung adenocarcinoma cells. Furthermore, tumor formation was inhibited by knockdown of LINC00466 or overexpression of miR-144. Taken together, LINC00466 could restrain the miR-144 expression to up-regulate HOXA10 and therefore promote lung adenocarcinoma.
  • Integrated Molecular Analysis of Papillary Renal Cell Carcinoma and
           Precursor Lesions Unfolds Evolutionary Process from Kidney Progenitor-Like
    • Abstract: Publication date: Available online 2 August 2019Source: The American Journal of PathologyAuthor(s): Rola M. Saleeb, Mina Farag, Qiang Ding, Michelle Downes, Georg Bjarnason, Fadi Brimo, Pamela Plant, Fabio Rotondo, Zsuzsanna Lichner, Antonio Finelli, George M. Yousef Papillary renal cell carcinoma (PRCC) is the most common type of RCC in end-stage kidney disease (ESKD). Papillary adenoma (PA) is a small benign lesion morphologically similar to PRCC and is suggested by some to be its precursor. PA is also very prevalent in ESKD. The evolution of PAs to PRCCs and their relationship to ESKD is poorly understood. One-hundred and forty PAs, normal kidneys, ESKDs, and PRCCs were analyzed. Previously described markers of renal tubular progenitor cells were performed using immunohistochemistry and quantified with digital analysis (n=140). Progenitor cells were significantly increased in ESKD (P < 0.0001) and PAs (P = 0.02) in comparison to the normal kidney. Pathway analysis using global miRNA (n=12) and chromosomal Copy number variations (n=21) revealed a common developmental theme between PA and the PRCCs. Whole exome next-generation sequencing (n=12) showed a KMT2C specific pathogenic mutation among all PAs and PRCCs. KMT2C is a Chr 7 epigenetic regulator implicated in development and oncogenesis. Collectively results show a possible connection of PRCCs to PA and progenitor-like cell population, which are increased in response to renal tubular injury. Additionally, each PRCC histological subtype had its own set of mutational changes indicating divergence from a common precursor. The study reports previously unknown biological aspects of PRCC development; and could influence current surveillance criteria and early detection strategies of PRCC tumors.
  • Double-stranded RNA is a novel molecular target in osteomyelitis
           pathogenesis: a translational avian model for human bacterial
           chondronecrosis with osteomyelitis
    • Abstract: Publication date: Available online 2 August 2019Source: The American Journal of PathologyAuthor(s): Elizabeth Greene, Joshua Flees, Ahmed Dhamad, Adnan Alrubaye, Stephen Hennigan, Jason Pleimann, Mark Smeltzer, Sue Murray, Jennifer Kugel, James Goodrich, Avril Robertson, Robert Wideman, Douglas Rhoads, Sami Dridi Osteomyelitis remains a serious inflammatory bone disease that affects millions of individuals worldwide and for which there is no effective treatment. In spite of scientific evidence that Staphylococcus bacteria are the most common causative species for human bacterial chondronecrosis with osteomyelitis (BCO), much remains to be understood about the underlying virulence mechanisms. Here we show increased levels of dsRNA in infected bone in a Staphylococcus-induced chicken BCO model and in human osteomyelitis samples. Administration of synthetic (Poly:IC) or genetic (Alu) dsRNA induces human osteoblast cell death. Similarly, infection with Staphylococcus isolated from chicken BCO induces dsRNA accumulation and cell death in human osteoblast cell cultures. Both dsRNA administration and Staphylococcus infection activate NLRP3 inflammasome and increases IL18 and IL1B gene expression in human osteoblasts. Pharmacological inhibition with Ac-YVAD-cmk of caspase 1, a critical component of the NLRP3 inflammasome, prevents DICER1 dysregulation-, and dsRNA-induced osteoblast cell death. NLRP3 inflammasome and its components are also activated in bone from BCO chickens and humans with osteomyelitis, compared to their healthy counterparts. These findings provide a rationale for the use of chicken BCO as a human-relevant spontaneous animal model for osteomyelitis, and identify dsRNA as a new treatment target for this debilitating bone pathogenesis.
  • Blockade of Lymphangiogenesis Shapes Tumor-Promoting Adipose Tissue
    • Abstract: Publication date: Available online 29 July 2019Source: The American Journal of PathologyAuthor(s): Marek Wagner, Eli Sihn Steinskog, Helge WiigTumor-associated lymphangiogenesis correlates with lymph node metastasis and poor outcome in several human malignancies. Additionally, the presence of functional lymphatic vessels regulates the formation of tumor inflammatory and immune microenvironments. Although lymphatic structures are often found deeply integrated into the fabric of adipose tissue, the impact of lymphangiogenesis on tumor-associated adipose tissue has not yet been investigated. Using K14-VEGFR3-Ig mice that constitutively express soluble VEGFR3-Ig in the skin, scavenging VEGF-C and VEGF-D, the role of lymphangiogenesis in the generation of an inflammatory response within tumor-associated adipose tissue was studied. Macrophages expressing the hyaluronan receptor LYVE-1 were found within peritumoral adipose tissue from melanoma-bearing K14-VEGFR3-Ig mice, which were further enriched with alternatively activated macrophages based on surface marker CD301/CLEC10A expression. The blockade of lymphangiogenesis also resulted in accumulation of the cytokine interleukin-6, which correlated with enhanced macrophage proliferation of the alternatively activated phenotype. Furthermore, melanomas co-implanted with freshly isolated adipose tissue macrophages grew more robustly when compared with melanomas growing alone. In human cutaneous melanomas, adipocyte-selective FABP4 transcripts closely correlated with gene signatures of CLEC10A and were associated with poor overall survival. These data suggest that the blockade of pathways regulating lymphatic vessel formation shapes an inflammatory response within tumor-associated adipose tissue by facilitating accumulation of tumor-promoting alternatively activated macrophages.
  • Polymorphisms in RocA Contribute to the Molecular Pathogenesis of Serotype
           M28 Group A Streptococcus
    • Abstract: Publication date: Available online 29 July 2019Source: The American Journal of PathologyAuthor(s): Paul E. Bernard, Priyanka Kachroo, Jesus M. Eraso, Luchang Zhu, Jessica E. Madry, Sarah E. Linson, Matthew Ojeda Saavedra, Concepcion Cantu, James M. Musser, Randall J. OlsenTwo-component systems (TCSs) are signal transduction proteins that enable bacteria to respond to external stimuli by altering the global transcriptome. Accessory proteins interact with TCSs to fine-tune their activity. In group A streptococcus (GAS), RocA is an accessory protein that functions with the control of virulence regulator/sensor TCS, which regulates approximately 15% of the GAS transcriptome. Whole-genome sequencing analysis of serotype M28 GAS strains collected from invasive infections in humans identified a higher number of missense (amino acid altering) and nonsense (protein truncating) polymorphisms in rocA than expected. We hypothesized that polymorphisms in RocA alter the global transcriptome and virulence of serotype M28 GAS. We used naturally-occurring clinical isolates with rocA polymorphisms (n=48), an isogenic rocA deletion mutant strain, and five isogenic rocA polymorphism mutant strains to perform genome-wide transcript analysis (RNA-seq), in vitro virulence factor assays, and mouse and nonhuman primate pathogenesis studies to test this hypothesis. Results demonstrated that polymorphisms in rocA result in either a subtle transcriptome change causing a wild-type–like virulence phenotype, or a substantial transcriptome change leading to a significantly increased virulence phenotype. Each polymorphism had a unique effect on the global GAS transcriptome. Taken together, our data show that naturally-occurring polymorphisms in one gene encoding an accessory protein can significantly alter the global transcriptome and virulence phenotype of GAS, an important human pathogen.
  • The Origin of Follicular Bile Acids in the Human Ovary
    • Abstract: Publication date: Available online 29 July 2019Source: The American Journal of PathologyAuthor(s): Ruxandra A. Nagy, Harry Hollema, Daniela Andrei, Angelika Jurdzinski, Folkert Kuipers, Annemieke Hoek, Uwe J.F. TietgeBile acids (BA) are present in ovarian follicular fluid (FF) and have been linked to embryo development. However, information on the source of ovarian BA is scarce. Therefore, we aimed to explore local ovarian synthesis and BA transport from blood into FF. BA levels were determined in matching FF and serum from women who underwent in vitro fertilization. In vitro BA production by human mural (MCG) and cumulus granulosa cells (CGC) was measured by mass spectrometry. Gene and protein expression were quantified in human MCG and CGC and in human ovarian tissue by quantitative PCR and Western blot/immunohistochemistry, respectively. There was a significant correlation between the levels of BA in blood and FF (rs=0.186, P = 0.027). Interestingly, levels of FF BA were almost double those in blood (P < 0.001) with a higher percentage of primary BA, indicating that, in addition to passive diffusion, other sources of ovarian BA might exist. The key BA synthesis enzyme CYP7A1 was absent in MGC and CGC, and there was no evidence of BA production in vitro. Therefore, local ovarian BA production is unlikely. However, common BA importers (NTCP, ASBT) and an exporter (ABCC3) were identified in GC, theca cells, and the oocyte. In summary, these results suggest that passive and active transport of BA from blood into FF constitute sources of FF BA.
  • Activation of PINK1-Parkin–Mediated Mitophagy Degrades Mitochondrial
           Quality Control Proteins in Fuchs Endothelial Corneal Dystrophy
    • Abstract: Publication date: Available online 27 July 2019Source: The American Journal of PathologyAuthor(s): Takashi Miyai, Shivakumar Vasanth, Geetha Melangath, Neha Deshpande, Varun Kumar, Anne-Sophie Benischke, Yuming Chen, Marianne O. Price, Francis W. Price, Ula V. JurkunasCorneal endothelium (CE) is a monolayer of mitochondria-rich cells, critical for maintaining corneal transparency compatible with clear vision. Fuchs endothelial corneal dystrophy (FECD) is a heterogeneous genetically complex disorder, where oxidative stress plays a key role in the rosette formation during the degenerative loss of CE. Increased mitochondrial fragmentation along with excessive mitophagy activation has been detected in FECD; however, the mechanism of aberrant mitochondrial dynamics in CE cell loss is poorly understood. Here, we investigate the role of oxidative stress in mitophagy activation in FECD. Immunoblotting of FECD ex vivo specimens revealed an accumulation of PINK1 and phospho-Parkin (Ser65) along with loss of total Parkin and total Drp1. Similarly, modeling of rosette formation with menadione (MN), led to phospho-Parkin accumulation in fragmented mitochondria resulting in mitophagy-induced mitochondrial clearance, albeit possibly in a PINK1 independent manner. Loss of PINK1, phospho-Drp1 and total Drp1 was prominent after MN-induced oxidative stress, but not after mitochondrial depolarization by carbonyl cyanide m-chlorophenyl hydrazone (CCCP). Moreover, MN-induced mitophagy led to degradation of Parkin along with sequestration of Drp1 and PINK1 that was rescued by mitophagy inhibition. This study shows that in FECD intracellular oxidative stress induces Parkin-mediated mitochondrial fragmentation where endogenous Drp1 and PINK1 are sequestered and degraded by mitophagy during degenerative loss of post-mitotic cells of ocular tissue.
  • Mechanisms of ERBB3 Action in Human Neoplasia
    • Abstract: Publication date: Available online 25 July 2019Source: The American Journal of PathologyAuthor(s): Laurel Black, Jody Fromm Longo, Steven L. CarrollIt is well established that the epidermal growth factor receptor, ERBB2/HER2 and, to a lesser extent, ERBB4/HER4 promote the pathogenesis of many types of human cancers. In contrast, the role that ERBB3/HER3, the fourth member of the ERBB family of receptor tyrosine kinases, plays in these diseases is poorly understood and, until recently, underappreciated. In large part, this was because early structural and functional studies suggested that ERBB3 had little, if any, intrinsic tyrosine kinase activity and thus was unlikely to be an important therapeutic target. Since then, however, numerous publications have demonstrated an important role for ERBB3 in carcinogenesis, metastasis, and acquired drug resistance. Further, somatic ERBB3 mutations are frequently encountered in many types of human cancers. Dysregulation of ERBB3 trafficking as well as cooperation with other receptor tyrosine kinases further enhances ERBB3’s role in tumorigenesis and drug resistance. As a result of these advances in our understanding of the structure and biochemistry of ERBB3, and a growing focus on the development of precision and combinatorial therapeutic regimens, ERBB3 is increasingly considered to be an important therapeutic target in human cancers. In this review, we discuss the unique structural and functional features of ERBB3 and how this information is being used to develop effective new therapeutic agents that target ERBB3 in human cancers.
  • Antitumor Activity of a Novel Fibroblast Growth Factor Receptor (FGFR)
           Inhibitor for Intrahepatic Cholangiocarcinoma
    • Abstract: Publication date: Available online 24 July 2019Source: The American Journal of PathologyAuthor(s): Chiara Raggi, Karim Fiaccadori, Mirella Pastore, Margherita Correnti, Benedetta Piombanti, Elisa Forti, Nadia Navari, Giovanni Abbadessa, Terence Hall, Annarita Destro, Luca Di Tommaso, Massimo Roncalli, Fanyin Meng, Shannon Glaser, Elisabetta Rovida, Caterina Peraldo-Neia, Paula Olaizola, Jesus M. Banales, Alessio Gerussi, Alessandra ElveviFibroblast growth factor receptor 2 (FGFR2) might have an important role in the pathogenesis and biology of cholangiocarcinoma (CCA). We examined FGFR expression in CCA tumor specimens obtained from patients and CCA cell lines, and then determined the effects of the novel FGFR inhibitor, derazantinib (DZB, formally ARQ 087), which is currently in clinical phase 2 trials for intrahepatic CCA. DZB inhibited the growth of CCA cell lines in a dose-dependent manner, and ERK1/2 and AKT. It also activated apoptotic and cell growth arrest signaling. DZB reduced the in vitro invasiveness and the expression of key epithelial-to-mesenchymal transition genes. The in vitro data correlated with the expression of FGFRs in human CCA specimens by immunohistochemistry (FGFR1 30% and FGFR2 65% positive), and the CCA cell lines assayed by Western blot analysis. These correlated in vitro studies suggest that FGFR may play an important role in the pathogenesis and biology of CCA. Our findings support the notion that FGFR inhibitors, like DZB, should be further evaluated at the clinical stage as targeted therapy for CCA treatment.
  • Obesity-Associated Extracellular Matrix Remodeling Promotes a Macrophage
           Phenotype Similar to Tumor-Associated Macrophages
    • Abstract: Publication date: Available online 16 July 2019Source: The American Journal of PathologyAuthor(s): Nora L. Springer, Neil M. Iyengar, Rohan Bareja, Akanksha Verma, Maxine Jochelson, Dilip D. Giri, Xi Kathy Zhou, Olivier Elemento, Andrew J. Dannenberg, Claudia FischbachObesity is associated with adipose inflammation, defined by macrophages encircling dead adipocytes, as well as extracellular matrix (ECM) remodeling and increased risk of breast cancer. Whether ECM affects macrophage phenotype in obesity is uncertain. A better understanding of this relationship could be strategically important to reduce cancer risk or improve outcomes in the obese. Utilizing clinical samples, computational approaches, and in vitro decellularized ECM models, this study quantified the relative abundance of pro (M1)- and anti (M2)-inflammatory macrophages in human breast adipose tissue, determined molecular similarities between obesity and tumor-associated macrophages, and assessed the regulatory effect of obese versus lean ECM on macrophage phenotype. Our results suggest that breast adipose tissue contains more M2-biased than M1-biased macrophages across all body mass index (BMI) categories. Obesity further increased M2-biased macrophages but did not affect M1-biased macrophage density. Gene Set Enrichment Analysis (GSEA) suggested that breast tissue macrophages from obese versus lean women are more similar to tumor-associated macrophages (TAMs). These changes positively correlated with adipose tissue interstitial fibrosis, and in vitro experiments indicated that obese ECM directly stimulates M2-biased macrophage functions. However, mammographic density cannot be used as a clinical indicator of these changes. Collectively, these data suggest that obesity-associated interstitial fibrosis promotes a macrophage phenotype similar to TAMs, which may contribute to the link between obesity and breast cancer.
  • LRRC8A Expression Influences Growth of Esophageal Squamous Cell Carcinoma
    • Abstract: Publication date: Available online 16 July 2019Source: The American Journal of PathologyAuthor(s): Tomoki Konishi, Atsushi Shiozaki, Toshiyuki Kosuga, Michihiro Kudou, Katsutoshi Shoda, Tomohiro Arita, Hirotaka Konishi, Shuhei Komatsu, Takeshi Kubota, Hitoshi Fujiwara, Kazuma Okamoto, Mitsuo Kishimoto, Eiichi Konishi, Yoshinori Marunaka, Eigo OtsujiThe volume-regulated anion channel is composed of leucine-rich repeat–containing protein A (LRRC8A), and is activated by hypotonic conditions to implement the process of regulatory volume decrease. The role of LRRC8A in regulating genes related to progression of esophageal squamous cell carcinoma (ESCC) was investigated, as well as the prognostic significance of LRRC8A expression in this tumor. Knockdown experiments were conducted using ESCC cell lines and LRRC8A siRNA to assess the influence of this protein on tumor function. In addition, the gene expression profile of ESCC was determined by microarray analysis. Immunohistochemistry was performed on 64 primary tumor samples from ESCC patients receiving radical esophagectomy. It was found that depletion of LRRC8A decreased cell proliferation and migration, and also promoted apoptosis. Microarray data demonstrated G1/S checkpoint regulation and up-regulation or down-regulation of PI3K/AKT signaling, MMP, and integrin signaling–related genes (including p21, p27, MMP1, and ITGAV) in LRRC8A-depleted cells. Immunohistochemistry showed that LRRC8A expression was related to the pT and pN categories, and strong LRRC8A expression was correlated with a worse prognosis of ESCC. These findings indicate that LRRC8A modulates tumor progression by influencing cell cycle, apoptosis, and migration, providing new insights into its function as an effector or biomarker of ESCC.
  • This Month in AJP
    • Abstract: Publication date: Available online 15 July 2019Source: The American Journal of PathologyAuthor(s):
  • Liver-Specific but Not Retina-Specific Hepcidin Knockout Causes Retinal
           Iron Accumulation and Degeneration
    • Abstract: Publication date: Available online 6 July 2019Source: The American Journal of PathologyAuthor(s): Bailey H. Baumann, Wanting Shu, Ying Song, Jacob Sterling, Zbynek Kozmik, Samira Littleton-Lakhal, Joshua L. DunaiefThe liver secretes hepcidin (Hepc) into the bloodstream to reduce blood iron levels. Hepc accomplishes this by triggering degradation of the only known cellular iron exporter ferroportin in the gut, macrophages, and the liver. We previously demonstrated that systemic HepcKO mice, which have high serum iron, develop retinal iron overload and degeneration. However, it was unclear whether this is caused by high blood iron levels or alternatively, due to retinal iron influx that would normally be regulated by retina-produced Hepc. To address this question, retinas of liver-specific (LS) and retina-specific (RS) HepcKO mice were studied. LS-Hepc KO mice had elevated blood and RPE iron levels and increased free (labile) iron levels in the retina despite an intact blood-retinal barrier. This led to RPE hypertrophy associated with lipofuscin-laden lysosome accumulation. Photoreceptors also degenerated focally. In contrast, there was no change in retinal or RPE iron levels or degeneration in the RS-HepcKO mice. These data indicate that high blood iron levels can lead to retinal iron accumulation and degeneration. High blood iron levels can occur in patients with hereditary hemochromatosis or result from use of iron supplements or multiple blood transfusions. Our results suggest that high blood iron levels may cause or exacerbate retinal disease.
  • Repeated Exposure to Streptococcus pneumoniae Exacerbates Chronic
           Obstructive Pulmonary Disease
    • Abstract: Publication date: Available online 18 June 2019Source: The American Journal of PathologyAuthor(s): Xuxu Gou, Qiao Zhang, Sunil More, Gayan Bamunuarachchi, Yurong Liang, Faizan Haider Khan, Rachel Maranville, Emily Zuniga, Changzheng Wang, Lin LiuStreptococcus pneumoniae (S. pneumoniae) is commonly found in patients with chronic obstructive pulmonary disease (COPD) and is linked to acute exacerbation of COPD. However, current clinical therapy neglects asymptomatic insidious S. pneumoniae colonization. We studied the roles of repeated exposure to S. pneumonia in COPD progression using a mouse model. C57BL/6J mice were intranasally inoculated with S. pneumoniae ST262 every four weeks with or without cigarette smoke (CS) exposure up to 20 weeks to maintain persistent S. pneumoniae (SP) presence in the lower airways. SP enhanced CS-induced inflammatory cell infiltration at 12 to 20 weeks of exposure. SP also increased CS-induced release of inflammatory cytokines, including interleukin-1β, tumor necrosis factor-α, interleukin-12 (p70), and interleukin-5 at 20 weeks of exposure. Moreover, a combination of CS and SP caused alveolar epithelial injury, a decline in lung function, and an increased expression of platelet activating factor receptor and bacterial load. Our results suggest that repeated exposure to S. pneumonia in lower airways exacerbates CS-induced COPD.
  • The Protective Role of Natriuretic Peptide Receptor 2 against High Salt
           Injury in the Renal Papilla
    • Abstract: Publication date: Available online 18 June 2019Source: The American Journal of PathologyAuthor(s): George J. Dugbartey, Breandan Quinn, Lingfeng Luo, Deanne M. Mickelsen, Sara K. Ture, Craig N. Morrell, Jan Czyzyk, Marvin M. Doyley, Chen Yan, Bradford C. Berk, Vyacheslav A. KorshunovMutations in natriuretic peptide receptor 2 (Npr2) gene cause a rare form of short-limbed dwarfism, but its physiologic effects have not been well studied. Human and mouse genetic data suggest that Npr2 in the kidney plays a role in salt homeostasis. Here, we described anatomical changes within renal papilla of Npr2 knockout (Npr2−/−) mice. Dramatic reduction was found in diuresis and albuminuria was evident after administration of 1% NaCl in drinking water in Npr2−/− and heterozygous (Npr2+/−) mice compared to their wild-type (Npr2+/+) littermates. There was indication of renal epithelial damage accompanied by high numbers of red blood cells and inflammatory cells (Mac2) and an increase of renal epithelial damage marker (TIM-1) in Npr2−/− mice. Addition of 1% NaCl tended to increase apoptotic cells (cleaved Caspase 3) in the renal papilla of Npr2−/− mice. In vitro, genetic silencing of the Npr2 abolished protective effects of C-type natriuretic peptide, a ligand for Npr2, against death of M-1 kidney epithelial cells exposed to 360mM NaCl. Finally, significantly lower levels of expression of the NPR2 protein were detected in renal samples of hypertensive compared to normotensive human subjects. Taken together, these findings suggest that Npr2 is essential to protect renal epithelial cells from high concentrations of salt and prevent kidney injury.
  • Müller Cell–Localized GPR81 (HCA1) Regulates Inner Retinal Vasculature
           via Norrin/Wnt Pathways
    • Abstract: Publication date: Available online 18 June 2019Source: The American Journal of PathologyAuthor(s): Ankush Madaan, Prabhas Chaudhari, Mathieu Nadeau-Vallée, David Hamel, Tang Zhu, Grant Mitchell, Mark Samuels, Sheetal Pundir, Rabah Dabouz, Colin Wayne Howe Cheng, Mohammad Ali Mohammad Nezhady, Jean-Sébastien Joyal, José Carlos Rivera, Sylvain ChemtobIschemic retinopathies (IRs) are characterized by a progressive microvascular degeneration followed by a post-ischemic aberrant neovascularization. To reinstate vascular supply and metabolic equilibrium to the ischemic tissue during IRs, a dysregulated production of growth factors and metabolic intermediates occurs, promoting retinal angiogenesis. Glycolysis-derived lactate highly produced during ischemic conditions has been associated with tumor angiogenesis and wound healing. Lactate exerts its biologic effects via a G-protein–coupled receptor 81 (GPR81) in several tissues; however, its physiological functions and mechanisms of action in the retina remain poorly understood. Here we show that GPR81 localized predominantly in Müller cells governs deep vascular complex formation during development and in ischemic retinopathy. Lactate-stimulated GPR81 Müller cells produce numerous angiogenic factors including Wnt ligands and particularly Norrin, which contributes significantly in triggering inner retinal blood vessel formation. Conversely, GPR81-null mice retina shows reduced inner vascular network formation associated with low levels of Norrin (and Wnt ligands). Lactate accumulation during IR, selectively activates GPR81-Erk1/2-Norrin signaling to accelerate inner retinal vascularization in WT animals, but not in retina of GPR81-null mice. Altogether, we reveal that lactate via GPR81-Norrin participates in inner vascular network development, and in restoration of the vasculature in response to injury. These findings suggest a new potential therapeutic target to alleviate ischemic diseases.
  • Corneal Sensory Experience via TRPV1 Accelerates the Maturation
           of Neonatal Tearing
    • Abstract: Publication date: Available online 18 June 2019Source: The American Journal of PathologyAuthor(s): Kai Jin, Toshihiro Imada, Shigeru Nakamura, Yusuke Izuta, Erina Oonishi, Michiko Shibuya, Hisayo Sakaguchi, Hirotaka Tanabe, Masataka Ito, Kimiaki Katanosaka, Kazuo TsubotaTearing maturates rapidly after birth, and external environmental challenges play a key role in promoting lacrimal functional maturation. However, little is known about the facilitative factors underlying this developmental process or the potential of application of these factors to treat hypofunction of the lacrimal gland. In this study, eye-opening and the subsequent ocular surface sensory experience, which is thought to be involved in postnatal maturation of lacrimal function, were investigated. Our results demonstrated that eye-opening after birth is essential for the maturation of neonatal tearing. The maturation process of lacrimal function is dependent on the ocular surface sensory experience via transient receptor potential cation channel subfamily member 1 after birth. This study provides, for the first time, important evidence of the sensory experience of the ocular surface in relation to the maturation of functional tear secretion during the postnatal period.
  • microRNA-24 Is Elevated in Ulcerative Colitis Patients and Regulates
           Intestinal Epithelial Barrier Function
    • Abstract: Publication date: Available online 18 June 2019Source: The American Journal of PathologyAuthor(s): Artin Soroosh, Carl Robert Rankin, Christos Polytarchou, Zulfiqar Ali Lokhandwala, Ami Patel, Lin Chang, Charalabos Pothoulakis, Dimitrios Iliopoulos, David Miguel PaduaInflammatory bowel disease is characterized by high levels of inflammation and loss of barrier integrity in the colon. The intestinal barrier is a dynamic network of proteins that encircle intestinal epithelial cells. microRNAs regulate protein-coding genes. In this study, microRNA-24 was found to be elevated in colonic biopsies and blood samples from ulcerative colitis (UC) patients compared to healthy controls. In the colon of UC patients, microRNA-24 is localized to intestinal epithelial cells which prompted an investigation of intestinal epithelial barrier function. Two intestinal epithelial cell lines were used to study the effect of miR-24 overexpression on barrier integrity. Overexpression of microRNA-24 in both cell lines led to diminished transepithelial electrical resistance and increased dextran flux, suggesting an effect on barrier integrity. Overexpression of microRNA-24 did not induce apoptosis or affect cell proliferation, suggesting that the effect of microRNA-24 on barrier function was due to an effect on cell-cell junctions. Although the tight junctions in cells overexpressing microRNA-24 appeared normal, microRNA-24 overexpression led to a decrease in the tight junction–associated protein cingulin. Loss of cingulin compromised barrier formation;cingulin levels negatively correlated with disease severity in UC patients. Together, these data suggest that microRNA-24 is a significant regulator of intestinal barrier that may be important in the pathogenesis of UC.
  • Detection and classification of novel renal histological phenotypes using
           deep neural networks
    • Abstract: Publication date: Available online 18 June 2019Source: The American Journal of PathologyAuthor(s): Susan Sheehan, Seamus Mawe, Rachel E. Cianciolo, Ron Korstanje, J. Matthew Mahoney With the advent and increased accessibility of deep neural networks (DNNs), complex properties of histological images can be rigorously and reproducibly quantified. We used DNN-based transfer learning to analyze histological images of Periodic acid-Schiff–stained renal sections from a cohort of mice with different genotypes. We demonstrate that DNN-based machine learning has strong generalization performance on multiple histological image processing tasks. The neural network extracted quantitative image features and used them as classifiers to look for differences between mice of different genotypes. Excellent performance was observed at segmenting glomeruli from non-glomerular structure and subsequently predict the genotype of the animal based on glomerular quantitative image features. The DNN-based genotype classifications highly correlate with mesangial matrix expansion scored by a pathologist, which differed in these animals. Additionally, by analyzing non-glomeruli images, the neural network identified novel histological features that differed by genotype, including the presence of vacuoles, nuclear count, and proximal tubule brush border integrity, which was validated with immunohistological staining. These features were not identified in systematic pathological examination. Our study demonstrates the power of DNNs to extract biologically relevant phenotypes and serve as a platform for discovering novel phenotypes. These results highlight the synergistic possibilities for pathologists and DNNs to radically scale up our ability to generate novel mechanistic hypotheses in disease.
  • Involvement of α-Melanocyte-Stimulating Hormone-Thromboxane A2 System on
           Itching in Atopic Dermatitis
    • Abstract: Publication date: Available online 18 June 2019Source: The American Journal of PathologyAuthor(s): Tsugunobu Andoh, Chihiro Akasaka, Kyoko Shimizu, Jung-Bum Lee, Yoko Yoshihisa, Tadamichi Shimizuα-Melanocyte-stimulating hormone (α-MSH) is an endogenous peptide hormone involved in cutaneous pigmentation in atopic dermatitis (AD) with severe itching. α-MSH elicits itch-related responses in mice. We therefore investigated whether α-MSH was involved in itching in AD. In the skin of AD patients and mice with atopy-like dermatitis, α-MSH and the prohormone convertase 2, which is the key processing enzyme for the production of α-MSH, were distributed mainly in keratinocytes. In the skin of mice with dermatitis, α-MSH receptors (MC1R and MC5R) were expressed at the mRNA level and were distributed in the dermis. In the dorsal root ganglion (DRG) of mice with dermatitis, mRNAs encoding MC1 and MC3∼5 were also expressed. MC1R antagonist agouti-signaling protein inhibited spontaneous scratching in mice with dermatitis. In healthy mice, intradermal α-MSH elicited itch-associated responses, which were inhibited by TP thromboxane (TX) receptor antagonist ONO-3708. In mouse keratinocytes, α-MSH increased the production of TXA2, which was inhibited by adenylyl cyclase inhibitor SQ-22536 and Ca2+ chelator EGTA. In mouse keratinocytes treated with siRNA for MC1R and/or MC5R, α-MSH–induced TXA2 production was decreased. α-MSH increased intracellular Ca2+ ion concentration in DRG neurons and keratinocytes. These results suggest that α-MSH is involved in itching during AD and may elicit itching through the direct action of primary afferents and TXA2 production by keratinocytes.
  • The Expression of Yes-Associated Protein (YAP) Maintains Putative Cancer
           Stemness and Is Associated with Poor Prognosis in Intrahepatic
    • Abstract: Publication date: Available online 18 June 2019Source: The American Journal of PathologyAuthor(s): Kensuke Sugiura, Takashi Mishima, Shigetsugu Takano, Hideyuki Yoshitomi, Katsunori Furukawa, Tsukasa Takayashiki, Satoshi Kuboki, Mamoru Takada, Masaru Miyazaki, Masayuki OhtsukaIntrahepatic cholangiocarcinoma (ICC) is resistant to most chemotherapeutic agents. Yes-associated protein (YAP) is related to tumor progression; however, its role in ICC remains unknown. We investigated the mechanism underlying YAP-mediated cancer progression by focusing on the property of cancer stem cells (CSCs) in ICC. Immunohistochemistry results revealed the positive YAP expression in 37 of 52 resected ICC cases. Those with positive YAP expression showed poor prognosis in Kaplan-Meier analysis (P = 0.023). YAP expression was associated with vimentin and the putative CSC marker, OV-6. The knockdown of YAP expression using specific small-interfering RNAs in ICC cells decreased OCT4 expression in Western blotting, and OV-6 and CD133 expression in flow cytometry analysis. Verteporfin, a YAP inhibitor, decreased N-cadherin and OCT4 expression in Western blotting. In vitro sphere formation and anoikis resistance assays revealed the impairment in CSC property and anoikis resistance in response to the decrease in YAP expression. Verteporfin treatment activated the protein kinase B/mechanistic target of rapamycin (mTOR) signal pathway and dramatically impaired interleukin-6–stimulated signal transducer and activator of transcription-3 phosphorylation in ICC cells. The combination of verteporfin and rapamycin, an inhibitor of mTOR phosphorylation, inhibited cell proliferation and tumor growth. In conclusion, verteporfin regulates multiple signaling pathways and in combination with rapamycin, might be a promising therapeutic strategy for ICC treatment.
  • Neutral Sphingomyelinase 2 (SMPD3)-Deficiency in Mice Causes
           Chondrodysplasia with Unimpaired Skeletal Mineralization
    • Abstract: Publication date: Available online 12 June 2019Source: The American Journal of PathologyAuthor(s): Wilhelm Stoffel, Ina Hammels, Britta Jenke, Inga Schmidt-Soltau, Anja NiehoffSMPD3 deficiency in the neutral sphingomyelinase (Smpd3−/−) mouse results in a novel form of juvenile dwarfism, suggesting smpd3 as polygenetic determinant of body-height. SMPD3 controls homeostasis of the sphingomyelin cycle in the Golgi-compartment, essential for membrane remodeling, initiating multiform vesicle formation and transport in the Golgi secretory pathway. Using the unbiased Smpd3−/− genetic model, this study shows that the perturbed Golgi secretory pathway of chondrocytes of the epiphyseal growth zone leads to dysproteostasis, skeletal growth inhibition, malformation, and chondrodysplasia, but revealed unimpaired mineralization in primary and secondary enchondral ossification centers. This has been elaborated by biochemical analyses and immuno-histochemistry of long bones of Smpd3−/− mice. A more precise definition of the microarchitecture and three dimensional structure of the bone was asserted by peripheral quantitative computed tomography, high resolution microcomputed tomography, and less precise by dual-energy X-ray absorptiometry for osteodensitometry. Ablation of the Smpd3-locus as part of a 980 kb-deletion on chromosome 8 in the fro/fro mutant, generated by chemical mutagenesis, is held responsible for skeletal hypomineralization, osteoporosis, multiple fractures of long bones, which are hallmarks of human osteogenesis imperfecta (OI). The phenotype of the genetically unbiased Smpd3−/− mouse, described here, precludes the proposed role of Smpd3 as a candidate gene of human OI, but suggests SMPD3-deficiency as the pathogenetic basis of a novel form of chondrodysplasia.
  • Diverse Consequences in Liver Injury in Mice with Different Autophagy
           Functional Status Treated with Alcohol
    • Abstract: Publication date: Available online 11 June 2019Source: The American Journal of PathologyAuthor(s): Shengmin Yan, Jun Zhou, Xiaoyun Chen, Zheng Dong, Xiao-Ming YinAlcoholic fatty liver disease is often complicated by other pathological insults, such as viral infection or high fat diet. Autophagy plays a homeostatic role in the liver but can be compromised by alcohol, high fat diet, or viral infection, which in turn affect the disease process caused by these etiologies. To understand the full impact of autophagy modulation on alcohol-induced liver injury, several genetic models of autophagy deficiency, which have different levels of functional alterations, were examined following acute binge or chronic-plus-binge treatment. Alcohol given in either mode to the liver-specific inducible Atg7-deficient mice shortly after the induction of Atg7 deletion had an elevated liver injury, indicating the protective role of autophagy. Constitutive hepatic Atg7 deficient mice, in which Atg7 was deleted in embryos, were more susceptible to chronic-plus-binge but not to acute alcohol treatment. Constitutive hepatic Atg5 deficient mice, in which Atg5 was deleted in embryos, were more prone to acute alcohol treatment, but liver injury were surprisingly improved in the chronic-plus-binge regime. A prolonged autophagy deficiency may complicate the hepatic response to alcohol treatment, likely in part due to endogenous liver injury. The complexity of the relationship between autophagy deficiency and alcohol-induced liver injury can thus be affected by the timing of autophagy dysfunction, the exact autophagy gene being affected, and the alcohol treatment regime.
  • Dynamic Regulation of Caveolin-1 Phosphorylation and Caveolae Formation by
           mTORC2 in Bladder Cancer Cells
    • Abstract: Publication date: Available online 11 June 2019Source: The American Journal of PathologyAuthor(s): Andrew M. Hau, Sounak Gupta, Mariah Z. Leivo, Kazufumi Nakashima, Jesus Macias, Weidong Zhou, Alex Hodge, Julie Wulfkuhle, Brian Conkright, Krithika Bhuvaneshwar, Shruti Rao, Subha Madhavan, Emanuel F. Petricoin, Donna E. HanselThe mammalian target of rapamycin and associated PI3K/AKT/mammalian target of rapamycin (mTOR) signaling pathway is commonly up-regulated in cancer, including bladder cancer. The mammalian target of rapamycin complex 2 (mTORC2) is a major regulator of bladder cancer cell migration and invasion, but the mechanisms by which mTORC2 regulates these processes are unclear. A discovery mass-spectrometry (MS) and reverse-phase protein array (RPPA)-based proteomics dual approach was used to identify novel mTORC2 phosphoprotein targets in actively invading cancer cells. mTORC2 targets included focal adhesion kinase, proto-oncogene tyrosine-protein kinase Src, and caveolin-1 (Cav-1), among others. Functional testing shows that mTORC2 regulates Cav-1 localization and dynamic phosphorylation of Cav-1 on Y14. Regulation of Cav-1 activity by mTORC2 also alters the abundance of caveolae, which are specialized lipid raft invaginations of the plasma membrane associated with cell signaling and membrane compartmentalization. Our results demonstrate a unique role for mTORC2-mediated regulation of caveolae formation in actively migrating cancer cells.
  • Pathology Image Analysis Using Segmentation Deep Learning Algorithms
    • Abstract: Publication date: Available online 11 June 2019Source: The American Journal of PathologyAuthor(s): Shidan Wang, Donghan M. Yang, Ruichen Rong, Xiaowei Zhan, Guanghua XiaoWith the rapid development of image scanning techniques and visualization software, whole slide imaging (WSI) is becoming a routine diagnostic method. Accelerating clinical diagnosis from pathology images and automating image analysis efficiently and accurately remain significant challenges. Recently, deep learning algorithms have shown great promise in pathology image analysis, such as in tumor region identification, metastasis detection and patient prognosis. Many machine learning algorithms, including convolutional neural networks, have been proposed to automatically segment pathology images. Among these algorithms, segmentation deep learning algorithms such as fully-convolutional networks stand out for their accuracy, computational efficiency, and generalizability. Thus, deep learning–based pathology image segmentation has become an important tool in WSI analysis. In this review, we describe the pathology image segmentation process using deep learning algorithms in detail. The goals are to provide quick guidance for implementing deep learning into pathology image analysis, and to provide some potential ways of further improving segmentation performance. Although there have been previous reviews on using machine learning methods in digital pathology image analysis, to our knowledge, this is the first in-depth review of the applications of deep learning algorithms for segmentation in WSI analysis.
  • Expression Profiling Reveals Involvement of WNT Pathway in the Malignant
           Progression of Sessile Serrated Adenomas
    • Abstract: Publication date: Available online 11 June 2019Source: The American Journal of PathologyAuthor(s): Mahra Nourbakhsh, Adnan Mansoor, Konstantin Koro, Qingrun Zhang, Parham MinooApproximately 15% to 20% of colorectal cancers are developed through the serrated pathway of tumorigenesis which is associated with BRAF mutation, CpG island methylation phenotype, and MLH1 methylation. However, the detailed process of progression from sessile serrated adenoma (SSA) to dysplasia and carcinoma has not been elucidated. To further characterize mechanisms involved in the dysplastic progression of SSA, we investigated differential expressions of mRNAs between areas with and without dysplasia within same SSA polyps. Significantly dysregulated genes in paired samples were applied for functional annotation and biological significance using Ingenuity Pathway Analysis software and Database for Annotation, Visualization and Integrity Discovery (DAVID). The same lysates from a subset of matched samples were subjected for miRNA expression profiling. Differentially expressed miRNAs were determined, and their targeted mRNAs were compared in parallel to the list of differentially expressed mRNAs from RNA sequencing study. Fourteen common mRNA targets were identified, which include AXIN2, a known indicator of WNT/B-catenin pathway activation. Together, in this study, different genes/pathways/biological processes involved in the initiation and progression of dysplasia in the serrated pathway are documented. One of the most significant findings is the involvement of WNT/B-catenin pathway in the dysplastic progression of SSAs with different genes being targeted in early versus advanced dysplasia.
  • The Clinical Autopsy and Genetic Testing
    • Abstract: Publication date: Available online 11 June 2019Source: The American Journal of PathologyAuthor(s): Jeffrey Sklar
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