15 results on '"Bahar-Shany K"'
Search Results
2. FOXO3a loss is a frequent early event in high-grade pelvic serous carcinogenesis
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Levanon, K, Sapoznik, S, Bahar-Shany, K, Brand, H, Shapira-Frommer, R, Korach, J, Hirsch, M S, Roh, M H, Miron, A, Liu, J F, Vena, N, Ligon, A H, Fotheringham, S, Bailey, D, Flavin, R J, Birrer, M J, and Drapkin, R I
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- 2014
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3. FOXO3a loss is a frequent early event in high-grade pelvic serous carcinogenesis
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Levanon, K, primary, Sapoznik, S, additional, Bahar-Shany, K, additional, Brand, H, additional, Shapira-Frommer, R, additional, Korach, J, additional, Hirsch, M S, additional, Roh, M H, additional, Miron, A, additional, Liu, J F, additional, Vena, N, additional, Ligon, A H, additional, Fotheringham, S, additional, Bailey, D, additional, Flavin, R J, additional, Birrer, M J, additional, and Drapkin, R I, additional
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- 2013
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4. Upregulation of MMP-9 production by TNFα in keratinocytes and its attenuation by vitamin D
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Bahar-Shany, K., primary, Ravid, A., additional, and Koren, R., additional
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- 2009
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5. Upregulation of MMP-9 production by TNFα in keratinocytes and its attenuation by vitamin D.
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BAHAR-SHANY, K., RAVID, A., and KOREN, R.
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METALLOPROTEINASES , *TUMOR necrosis factors , *METABOLITES , *KERATINOCYTES , *PROTEIN kinases - Abstract
MMP-9, a member of the matrix metalloproteinase family that degrades collagen IV and processes chemokines and cytokines, participates in epidermal remodeling in response to stress and injury. Limited activity of MMP-9 is essential while excessive activity is deleterious to the healing process. Tumor necrosis factor (TNFα), a key mediator of cutaneous inflammation, is a powerful inducer of MMP-9. Calcitriol, the hormonally active vitamin D metabolite, and its analogs are known to attenuate epidermal inflammation. We aimed to examine the modulation of MMP-9 by calcitriol in TNFα-treated keratinocytes. The immortalized HaCaT keratinocytes were treated with TNFα in the absence of exogenous growth factors or active ingredients. MMP-9 production was quantified by gelatin zymography and real-time RT-PCR. Activation of signaling cascades was assessed by western blot analysis and DNA-binding activity of transcription factors was determined by EMSA. Exposure to TNFα markedly increased the protein and mRNA levels of MMP-9, while pretreatment with calcitriol dose dependently reduced this effect. Employing specific inhibitors we established that the induction of MMP-9 by TNFα was dependent on the activity of the epidermal growth factor receptor, c-Jun-N-terminal kinase (JNK), NFκB and extracellular signal-regulated kinase-1/2. The effect of calcitriol was associated with inhibition of JNK activation and reduction of DNA-binding activities of the transcription factors activator protein-1 (AP-1) and NFκB following treatment with TNFα. By down-regulating MMP-9 levels active vitamin D derivatives may attenuate deleterious effects due to excessive TNFα-induced proteolytic activity associated with cutaneous inflammation. J. Cell. Physiol. 222: 729–737, 2010. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]
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- 2010
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6. The human tumor microbiome is composed of tumor type-specific intracellular bacteria
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Adina Weinberger, Ron Shaoul, Morgan G. I. Langille, Alexandria P. Cogdill, Giuseppe Mallel, Talia Golan, Anat Ronai, Arnon Meltser, Vancheswaran Gopalakrishnan, Christian U. Blank, Jennifer A. Wargo, Einav Yehuda-Shnaidman, Tali Dadosh, Maya Dadiani, Daniel S. Peeper, Merav Rokah, Alon Ben-Nun, Reetakshi Arora, Elinor Gigi, Aviram Nissan, Keren Levanon, Zachary A. Cooper, Tatiana Dorfman, Gavin M. Douglas, Iris Kamer, Gabriel Ologun, Ilana Livyatan, Zvi R. Cohen, Iris Barshack, Noam Shental, Elisa A. Rozeman, Nicola Baldini, Einav Nili Gal-Yam, Nancy Gavert, Shlomit Yust-Katz, Ran Kremer, Eran Segal, Ravid Straussman, Roi Weiser, Yaara Zwang, Yuval Bussi, Hagit Shapira, Tehila Atlan, Dan J. Raz, Amnon Amit, Smadar Levin-Zaidman, Bella Kaufman, Aviva Rotter-Maskowitz, Keren Bahar-Shany, Tali Siegal, Abdul Wadud Khan, Judith Sandbank, Deborah Nejman, Gili Perry, Jair Bar, Maya Lotan-Pompan, Sofia Avnet, Ofra Golani, Garold Fuks, Leore T. Geller, Sagi Harnof, Nejman D., Livyatan I., Fuks G., Gavert N., Zwang Y., Geller L.T., Rotter-Maskowitz A., Weiser R., Mallel G., Gigi E., Meltser A., Douglas G.M., Kamer I., Gopalakrishnan V., Dadosh T., Levin-Zaidman S., Avnet S., Atlan T., Cooper Z.A., Arora R., Cogdill A.P., Khan M.A.W., Ologun G., Bussi Y., Weinberger A., Lotan-Pompan M., Golani O., Perry G., Rokah M., Bahar-Shany K., Rozeman E.A., Blank C.U., Ronai A., Shaoul R., Amit A., Dorfman T., Kremer R., Cohen Z.R., Harnof S., Siegal T., Yehuda-Shnaidman E., Gal-Yam E.N., Shapira H., Baldini N., Langille M.G.I., Ben-Nun A., Kaufman B., Nissan A., Golan T., Dadiani M., Levanon K., Bar J., Yust S., Barshack I., Peeper D.S., Raz D.J., Segal E., Wargo J.A., Sandbank J., Shental N., and Straussman R.
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0301 basic medicine ,Male ,Colon ,Macrophage ,medicine.medical_treatment ,Biology ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,Breast cancer ,RNA, Ribosomal, 16S ,medicine ,Microbiome ,Breast ,Lung ,Multidisciplinary ,Bacteria ,Melanoma ,Intracellular parasite ,Microbiota ,Ovary ,Cancer ,Immunotherapy ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Cancer research ,Neoplasm ,Female ,Pancreas ,Human - Abstract
Profiling tumor bacteria Bacteria are well-known residents in human tumors, but whether their presence is advantageous to the tumors or to the bacteria themselves has been unclear. As an initial step toward addressing this question, Nejman et al. produced an exhaustive catalog of the bacteria present in more than 1500 human tumors representing seven different tumor types (see the Perspective by Atreya and Turnbaugh). They found that the bacteria within tumors were localized within both cancer cells and immune cells and that the bacterial composition varied according to tumor type. Certain biologically plausible associations were identified. For example, breast cancer subtypes characterized by increased oxidative stress were enriched in bacteria that produce mycothiol, which can detoxify reactive oxygen species. Science , this issue p. 973 ; see also p. 938
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- 2020
7. Proteomic signature for detection of high-grade ovarian cancer in germline BRCA mutation carriers.
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Bahar-Shany K, Barnabas GD, Deutsch L, Deutsch N, Glick-Saar E, Dominissini D, Sapoznik S, Helpman L, Perri T, Blecher A, Katz G, Yagel I, Rosenblatt O, Shai D, Brandt B, Meyer R, Mohr-Sasson A, Volodarsky-Perel A, Zilberman I, Armon S, Jakobson-Setton A, Eitan R, Kadan Y, Beiner M, Josephy D, Brodsky M, Friedman E, Anafi L, Molchanov Y, Korach J, Geiger T, and Levanon K
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- Humans, Female, Adult, Genes, BRCA2, Mutation, Proteomics, Salpingo-oophorectomy, BRCA1 Protein genetics, Ovariectomy, Germ-Line Mutation, Genetic Predisposition to Disease, Ovarian Neoplasms diagnosis, Ovarian Neoplasms genetics, Ovarian Neoplasms pathology, Breast Neoplasms genetics
- Abstract
No current screening methods for high-grade ovarian cancer (HGOC) guarantee effective early detection for high-risk women such as germline BRCA mutation carriers. Therefore, the standard-of-care remains risk-reducing salpingo-oophorectomy (RRSO) around age 40. Proximal liquid biopsy is a promising source of biomarkers, but sensitivity has not yet qualified for clinical implementation. We aimed to develop a proteomic assay based on proximal liquid biopsy, as a decision support tool for monitoring high-risk population. Ninety Israeli BRCA1 or BRCA2 mutation carriers were included in the training set (17 HGOC patients and 73 asymptomatic women), (BEDOCA trial; ClinicalTrials.gov Identifier: NCT03150121). The proteome of the microvesicle fraction of the samples was profiled by mass spectrometry and a classifier was developed using logistic regression. An independent cohort of 98 BRCA mutation carriers was used for validation. Safety information was collected for all women who opted for uterine lavage in a clinic setting. We present a 7-protein diagnostic signature, with AUC >0.97 and a negative predictive value (NPV) of 100% for detecting HGOC. The AUC of the biomarker in the independent validation set was >0.94 and the NPV >99%. The sampling procedure was clinically acceptable, with favorable pain scores and safety. We conclude that the acquisition of Müllerian tract proximal liquid biopsies in women at high-risk for HGOC and the application of the BRCA-specific diagnostic assay demonstrates high sensitivity, specificity, technical feasibility and safety. Similar classifier for an average-risk population is warranted., (© 2022 UICC.)
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- 2023
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8. RNA biomarkers from proximal liquid biopsy for diagnosis of ovarian cancer.
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Hulstaert E, Levanon K, Morlion A, Van Aelst S, Christidis AA, Zamar R, Anckaert J, Verniers K, Bahar-Shany K, Sapoznik S, Vandesompele J, and Mestdagh P
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- Case-Control Studies, Early Detection of Cancer, Female, Humans, MicroRNAs genetics, Prognosis, RNA, Messenger genetics, Biomarkers, Tumor, Cell-Free Nucleic Acids, Liquid Biopsy methods, Ovarian Neoplasms diagnosis, Ovarian Neoplasms genetics, RNA
- Abstract
Background: Most ovarian cancer patients are diagnosed at an advanced stage and have a high mortality rate. Current screening strategies fail to improve prognosis because markers that are sensitive for early stage disease are lacking. This medical need justifies the search for novel approaches using utero-tubal lavage as a proximal liquid biopsy., Methods: In this study, we explore the extracellular transcriptome of utero-tubal lavage fluid obtained from 26 ovarian cancer patients and 48 controls using messenger RNA (mRNA) capture and small RNA sequencing., Results: We observed an enrichment of ovarian and fallopian tube specific messenger RNAs in utero-tubal lavage fluid compared to other human biofluids. Over 300 mRNAs and 41 miRNAs were upregulated in ovarian cancer samples compared with controls. Upregulated genes were enriched for genes involved in cell cycle activation and proliferation, hinting at a tumor-derived signal., Conclusion: This is a proof-of-principle that mRNA capture sequencing of utero-tubal lavage fluid is technically feasible, and that the extracellular transcriptome of utero-tubal lavage should be further explored in larger cohorts to assess the diagnostic value of the biomarkers identified in this study., Impact: Proximal liquid biopsy from the gynecologic tract is a promising source for mRNA and miRNA biomarkers for diagnosis of early-stage ovarian cancer., Competing Interests: Declaration of Competing Interest The authors declare no potential conflicts of interest., (Copyright © 2021. Published by Elsevier Inc.)
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- 2022
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9. NF-κB-miR-155 axis activation mediates ovulation-induced oncogenic effects in fallopian tube epithelium.
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Brand H, Barnabas GD, Sapoznik S, Bahar-Shany K, Pozniak Y, Yung Y, Hourvitz A, Geiger T, Jacob-Hirsch J, and Levanon K
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- Adult, Aged, Aged, 80 and over, Apoptosis, Biomarkers, Tumor genetics, Cell Movement, Cell Proliferation, Cystadenocarcinoma, Serous genetics, Cystadenocarcinoma, Serous metabolism, Cystadenocarcinoma, Serous pathology, Fallopian Tubes metabolism, Female, Follicular Fluid metabolism, Humans, Middle Aged, NF-kappa B genetics, Ovarian Neoplasms genetics, Ovarian Neoplasms metabolism, Prognosis, Tumor Cells, Cultured, Biomarkers, Tumor metabolism, Fallopian Tubes pathology, Gene Expression Regulation, Neoplastic, MicroRNAs genetics, NF-kappa B metabolism, Ovarian Neoplasms pathology, Ovulation
- Abstract
The fallopian tube secretory epithelial cells (FTSECs) are the cell-of-origin of most high-grade serous ovarian carcinomas (HGSOC). FTSECs are repeatedly exposed to inflammation induced by follicular fluid (FF) that is released with every ovulation cycle throughout a woman's reproductive years. Uninterrupted ovulation cycles are an established risk factor for HGSOC. Stimuli present in the FF induce an inflammatory environment which may cause DNA damage eventually leading to serous tumorigenesis. With the aim of elucidating possible mechanistic pathways, we established an 'ex vivo persistent ovulation model' mimicking the repeated exposure of human benign fallopian tube epithelium (FTE) to FF. We performed mass spectrometry analysis of the secretome of the ex vivo cultures as well as confirmatory targeted expressional and functional analyses. We demonstrated activation of the NF-κB pathway and upregulation of miR-155 following short-term exposure of FTE to human FF. Increased expression of miR-155 was also detected in primary HGSOC tumors compared with benign primary human FTE and corresponded with changes in the expression of miR-155 target genes. The phenotype of miR-155 overexpression in FTSEC cell line is of increased migratory and altered adhesion capacities. Overall, activation of the NF-κB-miR-155 axis in FTE may represent a possible link between ovulation-induced inflammation, DNA damage, and transcriptional changes that may eventually lead to serious carcinogenesis., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)
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- 2020
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10. The human tumor microbiome is composed of tumor type-specific intracellular bacteria.
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Nejman D, Livyatan I, Fuks G, Gavert N, Zwang Y, Geller LT, Rotter-Maskowitz A, Weiser R, Mallel G, Gigi E, Meltser A, Douglas GM, Kamer I, Gopalakrishnan V, Dadosh T, Levin-Zaidman S, Avnet S, Atlan T, Cooper ZA, Arora R, Cogdill AP, Khan MAW, Ologun G, Bussi Y, Weinberger A, Lotan-Pompan M, Golani O, Perry G, Rokah M, Bahar-Shany K, Rozeman EA, Blank CU, Ronai A, Shaoul R, Amit A, Dorfman T, Kremer R, Cohen ZR, Harnof S, Siegal T, Yehuda-Shnaidman E, Gal-Yam EN, Shapira H, Baldini N, Langille MGI, Ben-Nun A, Kaufman B, Nissan A, Golan T, Dadiani M, Levanon K, Bar J, Yust-Katz S, Barshack I, Peeper DS, Raz DJ, Segal E, Wargo JA, Sandbank J, Shental N, and Straussman R
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- Bacteria genetics, Bacteria isolation & purification, Breast microbiology, Colon microbiology, Female, Humans, Immunotherapy, Lung microbiology, Macrophages microbiology, Male, Neoplasms therapy, Ovary microbiology, RNA, Ribosomal, 16S genetics, Bacteria classification, Microbiota, Neoplasms microbiology
- Abstract
Bacteria were first detected in human tumors more than 100 years ago, but the characterization of the tumor microbiome has remained challenging because of its low biomass. We undertook a comprehensive analysis of the tumor microbiome, studying 1526 tumors and their adjacent normal tissues across seven cancer types, including breast, lung, ovary, pancreas, melanoma, bone, and brain tumors. We found that each tumor type has a distinct microbiome composition and that breast cancer has a particularly rich and diverse microbiome. The intratumor bacteria are mostly intracellular and are present in both cancer and immune cells. We also noted correlations between intratumor bacteria or their predicted functions with tumor types and subtypes, patients' smoking status, and the response to immunotherapy., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)
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- 2020
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11. Microvesicle Proteomic Profiling of Uterine Liquid Biopsy for Ovarian Cancer Early Detection.
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Barnabas GD, Bahar-Shany K, Sapoznik S, Helpman L, Kadan Y, Beiner M, Weitzner O, Arbib N, Korach J, Perri T, Katz G, Blecher A, Brandt B, Friedman E, Stockheim D, Jakobson-Setton A, Eitan R, Armon S, Brand H, Zadok O, Aviel-Ronen S, Harel M, Geiger T, and Levanon K
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- Female, Gene Expression Regulation, Neoplastic, Humans, Liquid Biopsy, Neoplasm Grading, Neoplasm Proteins metabolism, Ovarian Neoplasms genetics, Reproducibility of Results, Cell-Derived Microparticles metabolism, Early Detection of Cancer, Ovarian Neoplasms diagnosis, Ovarian Neoplasms pathology, Proteomics methods, Uterus pathology
- Abstract
High-grade ovarian cancer (HGOC) is the leading cause of mortality from gynecological malignancies, because of diagnosis at a metastatic stage. Current screening options fail to improve mortality because of the absence of early-stage-specific biomarkers. We postulated that a liquid biopsy, such as utero-tubal lavage (UtL), may identify localized lesions better than systemic approaches of serum/plasma analysis. Further, while mutation-based assays are challenged by the rarity of tumor DNA within nonmutated DNA, analyzing the proteomic profile, is expected to enable earlier detection, as it reveals perturbations in both the tumor as well as in its microenvironment. To attain deep proteomic coverage and overcome the high dynamic range of this body fluid, we applied our method for microvesicle proteomics to the UtL samples. Liquid biopsies from HGOC patients ( n = 49) and controls ( n = 127) were divided into a discovery and validation sets. Data-dependent analysis of the samples on the Q-Exactive mass spectrometer provided depth of 8578 UtL proteins in total, and on average ∼3000 proteins per sample. We used support vector machine algorithms for sample classification, and crossed three feature-selection algorithms, to construct and validate a 9-protein classifier with 70% sensitivity and 76.2% specificity. The signature correctly identified all Stage I lesions. These results demonstrate the potential power of microvesicle-based proteomic biomarkers for early cancer diagnosis., (© 2019 Barnabas et al.)
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- 2019
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12. Resistance to paclitaxel is associated with a variant of the gene BCL2 in multiple tumor types.
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Ben-Hamo R, Zilberberg A, Cohen H, Bahar-Shany K, Wachtel C, Korach J, Aviel-Ronen S, Barshack I, Barash D, Levanon K, and Efroni S
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Paclitaxel, the most commonly used form of chemotherapy, is utilized in curative protocols in different types of cancer. The response to treatment differs among patients. Biological interpretation of a mechanism to explain this personalized response is still unavailable. Since paclitaxel is known to target BCL2 and TUBB1, we used pan-cancer genomic data from hundreds of patients to show that a single-nucleotide variant in the BCL2 sequence can predict a patient's response to paclitaxel. Here, we show a connection between this BCL2 genomic variant, its transcript structure, and protein abundance. We demonstrate these findings in silico, in vitro, in formalin-fixed paraffin-embedded (FFPE) tissue, and in patient lymphocytes. We show that tumors with the specific variant are more resistant to paclitaxel. We also show that tumor and normal cells with the variant express higher levels of BCL2 protein, a phenomenon that we validated in an independent cohort of patients. Our results indicate BCL2 sequence variations as determinants of chemotherapy resistance. The knowledge of individual BCL2 genomic sequences prior to the choice of chemotherapy may improve patient survival. The current work also demonstrates the benefit of community-wide, integrative omics data sources combined with in-lab experimentation and validation sets., Competing Interests: The authors declare no competing interests.
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- 2019
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13. CCNE1 expression in high grade serous carcinoma does not correlate with chemoresistance.
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Sapoznik S, Aviel-Ronen S, Bahar-Shany K, Zadok O, and Levanon K
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Delayed diagnosis of ovarian cancer, as well as high recurrence rates and lack of personalized therapy options, are among the causes for poor survival figures. Much effort is made towards developing new therapeutic possibilities, however predictive biomarkers are still unavailable. CCNE1 amplification, occurring in ∼20% of the high grade serous ovarian tumors, was previously proposed as a marker for platinum resistance and poor prognosis as well as for CDK2 inhibition. The current study aimed to examine the role of CCNE1 positive-immunostain as a predictor of first-line taxane-platinum chemoresistance. We evaluated matched pre- vs. post-neoadjuvant chemotherapy tumor samples and correlated the degree of pathological response to treatment with CCNE1 expression levels. Our results indicate that CCNE1 immunohistochemistry does not predict taxane-platinum chemoresistance in ovarian cancer patients. Further research is required in order to enable personalized adjuvant treatment, in cases where poor pathological response is achieved after the neoadjuvant phase., Competing Interests: CONFLICTS OF INTEREST The authors have no conflicts of interest to declare.
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- 2017
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14. Activation-Induced Cytidine Deaminase Links Ovulation-Induced Inflammation and Serous Carcinogenesis.
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Sapoznik S, Bahar-Shany K, Brand H, Pinto Y, Gabay O, Glick-Saar E, Dor C, Zadok O, Barshack I, Zundelevich A, Gal-Yam EN, Yung Y, Hourvitz A, Korach J, Beiner M, Jacob J, Levanon EY, Barak M, Aviel-Ronen S, and Levanon K
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- B-Lymphocytes metabolism, B-Lymphocytes pathology, Cytidine Deaminase genetics, DNA Damage genetics, Epithelial Cells metabolism, Epithelial Cells pathology, Fallopian Tubes metabolism, Fallopian Tubes pathology, Female, Gene Expression Regulation, Neoplastic, Humans, Inflammation complications, Inflammation pathology, Ovarian Neoplasms complications, Ovarian Neoplasms pathology, Ovulation genetics, Ovulation metabolism, Carcinogenesis genetics, Cytidine Deaminase biosynthesis, Inflammation genetics, Ovarian Neoplasms genetics
- Abstract
In recent years, the notion that ovarian carcinoma results from ovulation-induced inflammation of the fallopian tube epithelial cells (FTECs) has gained evidence. However, the mechanistic pathway for this process has not been revealed yet. In the current study, we propose the mutator protein activation-induced cytidine deaminase (AID) as a link between ovulation-induced inflammation in FTECs and genotoxic damage leading to ovarian carcinogenesis. We show that AID, previously shown to be functional only in B lymphocytes, is expressed in FTECs under physiological conditions, and is induced in vitro upon ovulatory-like stimulation and in vivo in carcinoma-associated FTECs. We also report that AID activity results in epigenetic, genetic and genomic damage in FTECs. Overall, our data provides new insights into the etiology of ovarian carcinogenesis and may set the ground for innovative approaches aimed at prevention and early detection., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
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15. The involvement of matrix metalloproteinases 2 and 9 in rat retinal ischemia.
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Mathalone N, Lahat N, Rahat MA, Bahar-Shany K, Oron Y, and Geyer O
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- Animals, Blotting, Western, Disease Models, Animal, Enzyme Inhibitors therapeutic use, Guanidines therapeutic use, Ischemia pathology, Ischemia prevention & control, Male, Matrix Metalloproteinase Inhibitors, Minocycline therapeutic use, Nitric Oxide Synthase antagonists & inhibitors, Nitroarginine therapeutic use, Rats, Rats, Sprague-Dawley, Retinal Diseases pathology, Retinal Diseases prevention & control, Tissue Inhibitor of Metalloproteinase-1 metabolism, Ischemia enzymology, Matrix Metalloproteinase 2 metabolism, Matrix Metalloproteinase 9 metabolism, Retinal Diseases enzymology, Retinal Vessels
- Abstract
Background: The involvement of matrix metalloproteinases (MMPs) in ischemic tissue damage and remodeling has been reported by many investigators. Our study was designed to investigate the involvement of MMPs and of tissue inhibitors of metalloproteinases (TIMPs) in rat retinal ischemic injury, the effect of nitric oxide synthase (NOS) inhibitors on MMPs' activity in this model and whether minocycline (an MMP inhibitor) is protective in retinal ischemia., Methods: Ninety-four rats were used in the study. Ischemia was induced by 90 min elevation of intraocular pressure. MMPs' activities and the effect of NOS inhibitors [aminoguanidine (AG) or N-nitro-L-arginine (NNA)] and minocycline on MMPs' activities were assessed by zymography and TIMPs expression by Western analysis. Morphological damage was quantified by morphometry of hematoxylin and eosin-stained retinal sections., Results: Retinal extracts exhibited activities of proMMP-9 and proMMP-2. The activity of proMMP-9 increased immediately post ischemia (PI) and peaked to 4.6 times that of normal untreated controls in ischemic retinas and to 2.6 times that of controls in retinas of fellow sham-treated eyes at 24 h PI. The relative amount of TIMP-1 increased to 1.9-fold following ischemia and 2.5-fold in fellow sham-treated eyes at 24 h PI. ProMMP-2 activity increased more than two-fold immediately, at 24 h and at 48 h PI in ischemic retinas, and insignificantly in fellow sham-treated eyes. Treatment with 25 mg/kg AG or NNA caused a non-significant increase in proMMP-9 activity at 24 h PI (3.7- and 2.9-fold, respectively, p>0.6). There was no effect of AG or NNA on the activity of proMMP-2. Minocycline significantly attenuated the retinal ischemic damage, primarily by partially preserving ganglion cells and the inner plexiform layer. Minocyline (0.5 mg/ml or 5 mg/ml) inhibited MMPs' activities in ischemic retinal extracts in vitro., Conclusions: MMPs participated in morphological ischemic damage to rat retina. Treatment with minocycline dramatically attenuated damage to the retina.
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- 2007
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