1
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Chitra Veena S, Vajagathali M, Ramakrishnan V. A systematic review on the association between ovarian and prostate cancer with <I>BRCA1</I> and <I>BRCA2</I> gene. SIBERIAN JOURNAL OF ONCOLOGY 2023; 21:145-155. [DOI: 10.21294/1814-4861-2022-21-6-145-155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
Background. BRCA1 and BRCA2 were discussed as the basis of inherited adenocarcinoma and breast and ovarian malignancy. Ovarian cancer is uncommon in women below 40 years of age, and prostate cancer mainly occurs in older men cause 90 % in those above sixty-fve.Objective. The main objective of this paper is to investigate the relationship between ovarian and prostate cancer with the BRCA1 and BRCA2 genes.Material and Methods. The ovarian and prostate cancer mechanism is discussed in detail, and their preventive measures with screening techniques are also demonstrated. This systematic review collected the related articles from online databases using the key terms ovarian cancer, prostate cancer, BRCA genes, mutation, polymorphism, carcinoma, sarcoma, and genetic association.Results. Based on the obtained information, it is found that the BRCA genes are highly associated with prostate cancer in men, and in women, it is significantly linked with breast cancer than ovarian cancer.Conclusion. Therefore, early diagnosis and genetic testing for BRCA1&BRCA2 genes in both men and women are necessary. In some cases, these genes might even cause different types of cancer like pancreatic cancers. Identifying individuals with tumour-HRD through mutations in the homologous repair pathway and determining this gene expression is essential to improve treatment techniques developed during the previous decade and rapidly make their way into clinical trials practice. However, the safe introduction of these medicines into everyday practice will require a thorough understanding of treatment targets and associated adverse effects.
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Affiliation(s)
- Sarpparajan Chitra Veena
- Human Cytogenetics and Genomics Laboratory, Faculty of Allied Health Sciences, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Kelambakkam
| | - Mohammed Vajagathali
- Human Cytogenetics and Genomics Laboratory, Faculty of Allied Health Sciences, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Kelambakkam
| | - Veerabathiran Ramakrishnan
- Human Cytogenetics and Genomics Laboratory, Faculty of Allied Health Sciences, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Kelambakkam
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2
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Subhan A, Attia SA, P Torchilin V. Targeted siRNA nanotherapeutics against breast and ovarian metastatic cancer: a comprehensive review of the literature. Nanomedicine (Lond) 2021; 17:41-64. [PMID: 34930021 DOI: 10.2217/nnm-2021-0207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Metastasis is considered the major cause of unsuccessful cancer therapy. The metastatic development requires tumor cells to leave their initial site, circulate in the blood stream, acclimate to new cellular environments at a remote secondary site and endure there. There are several steps in metastasis, including invasion, intravasation, circulation, extravasation, premetastatic niche formation, micrometastasis and metastatic colonization. siRNA therapeutics are appreciated for their usefulness in treatment of cancer metastasis. However, siRNA therapy as a single therapy may not be a sufficient option for control of metastasis. By combining siRNA with targeting, functional agents or small-molecule drugs have shown potential effects that enhance therapeutic effectiveness. This review addresses multidrug resistance and metastasis in breast and ovarian cancers and highlights drug-delivery strategies using siRNA therapeutics.
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Affiliation(s)
- Abdus Subhan
- Department of Chemistry, ShahJalal University of Science & Technology, Sylhet 3114, Bangladesh
| | - Sara Aly Attia
- Center for Pharmaceutical Biotechnology and Nanomedicine, Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, USA
| | - Vladimir P Torchilin
- Center for Pharmaceutical Biotechnology and Nanomedicine, Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, USA.,Department of Oncology, Radiotherapy & Plastic Surgery, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, 119991, Russia
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3
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Wang T, Li Z, Yan L, Yan F, Shen H, Tian X. Long Non-Coding RNA Neighbor of BRCA1 Gene 2: A Crucial Regulator in Cancer Biology. Front Oncol 2021; 11:783526. [PMID: 34926299 PMCID: PMC8674783 DOI: 10.3389/fonc.2021.783526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 11/15/2021] [Indexed: 11/13/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) are involved in fundamental biochemical and cellular processes. The neighbor of BRCA1 gene 2 (NBR2) is a long intergenic non-coding RNA (lincRNA) whose gene locus is adjacent to the tumor suppressor gene breast cancer susceptibility gene 1 (BRCA1). In human cancers, NBR2 expression is dysregulated and correlates with clinical outcomes. Moreover, NBR2 is crucial for glucose metabolism and affects the proliferation, survival, metastasis, and therapeutic resistance in different types of cancer. Here, we review the precise molecular mechanisms underlying NBR2-induced changes in cancer. In addition, the potential application of NBR2 in the diagnosis and treatment of cancer is also discussed, as well as the challenges of exploiting NBR2 for cancer intervention.
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Affiliation(s)
- Ting Wang
- Department of Laboratory Medicine, Jiangsu Cancer Hospital & Jiangsu Institute of Cancer Research & The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, China
| | - Zhaosheng Li
- Department of Laboratory Medicine, Jiangsu Cancer Hospital & Jiangsu Institute of Cancer Research & The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, China
| | - Liujia Yan
- Department of Laboratory Medicine, Jiangsu Cancer Hospital & Jiangsu Institute of Cancer Research & The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, China
| | - Feng Yan
- Department of Laboratory Medicine, Jiangsu Cancer Hospital & Jiangsu Institute of Cancer Research & The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, China
| | - Han Shen
- Department of Laboratory Medicine, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing, China
| | - Xinyu Tian
- Department of Laboratory Medicine, Nanjing Drum Tower Hospital, Nanjing University Medical School, Nanjing, China
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4
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Zhang Q, Guan G, Cheng P, Cheng W, Yang L, Wu A. Characterization of an endoplasmic reticulum stress-related signature to evaluate immune features and predict prognosis in glioma. J Cell Mol Med 2021; 25:3870-3884. [PMID: 33611848 PMCID: PMC8051731 DOI: 10.1111/jcmm.16321] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 12/25/2020] [Accepted: 12/31/2020] [Indexed: 12/12/2022] Open
Abstract
Endoplasmic reticulum (ER) stress has considerable impact on cell growth, proliferation, metastasis, invasion, angiogenesis and chemoradiotherapy resistance in various cancers. However, the effect of ER stress on the outcomes of glioma patients remains unclear. In this study, we established an ER stress risk model based on The Cancer Genome Atlas (TCGA) glioma data set to reflect immune characteristics and predict the prognosis of glioma patients. Survival analysis indicated that there were significant differences in the overall survival (OS) of glioma patients with different ER stress-related risk scores. Moreover, the ER stress-related risk signature, which was markedly associated with the clinicopathological properties of glioma patients, could serve as an independent prognostic indicator. Functional enrichment analysis revealed that the risk model correlated with immune and inflammation responses, as well as biosynthesis and degradation. In addition, the ER stress-related risk model indicated an immunosuppressive microenvironment. In conclusion, we present an ER stress risk model that is an independent prognostic factor and indicates the general immune characteristics in the glioma microenvironment.
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Affiliation(s)
- Qing Zhang
- Department of Neurosurgery, The First Hospital of China Medical University, Shenyang, China
| | - Gefei Guan
- Department of Neurosurgery, The First Hospital of China Medical University, Shenyang, China
| | - Peng Cheng
- Department of Neurosurgery, The First Hospital of China Medical University, Shenyang, China
| | - Wen Cheng
- Department of Neurosurgery, The First Hospital of China Medical University, Shenyang, China
| | - Lianhe Yang
- Department of Pathology, First Affiliated Hospital and College of Basic Medical Sciences of China Medical University, Shenyang, China
| | - Anhua Wu
- Department of Neurosurgery, The First Hospital of China Medical University, Shenyang, China
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5
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Gendoo DMA, Zon M, Sandhu V, Manem VSK, Ratanasirigulchai N, Chen GM, Waldron L, Haibe-Kains B. MetaGxData: Clinically Annotated Breast, Ovarian and Pancreatic Cancer Datasets and their Use in Generating a Multi-Cancer Gene Signature. Sci Rep 2019; 9:8770. [PMID: 31217513 PMCID: PMC6584731 DOI: 10.1038/s41598-019-45165-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 05/31/2019] [Indexed: 12/13/2022] Open
Abstract
A wealth of transcriptomic and clinical data on solid tumours are under-utilized due to unharmonized data storage and format. We have developed the MetaGxData package compendium, which includes manually-curated and standardized clinical, pathological, survival, and treatment metadata across breast, ovarian, and pancreatic cancer data. MetaGxData is the largest compendium of curated transcriptomic data for these cancer types to date, spanning 86 datasets and encompassing 15,249 samples. Open access to standardized metadata across cancer types promotes use of their transcriptomic and clinical data in a variety of cross-tumour analyses, including identification of common biomarkers, and assessing the validity of prognostic signatures. Here, we demonstrate that MetaGxData is a flexible framework that facilitates meta-analyses by using it to identify common prognostic genes in ovarian and breast cancer. Furthermore, we use the data compendium to create the first gene signature that is prognostic in a meta-analysis across 3 cancer types. These findings demonstrate the potential of MetaGxData to serve as an important resource in oncology research, and provide a foundation for future development of cancer-specific compendia.
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Affiliation(s)
- Deena M A Gendoo
- Centre for Computational Biology, Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, United Kingdom.
| | - Michael Zon
- Princess Margaret Cancer Center, University Health Network, Toronto, M5G 2C1, Canada.,Department of Biomedical Engineering, McMaster University, Toronto, L8S 4L8, Canada
| | - Vandana Sandhu
- Princess Margaret Cancer Center, University Health Network, Toronto, M5G 2C1, Canada
| | - Venkata S K Manem
- Princess Margaret Cancer Center, University Health Network, Toronto, M5G 2C1, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, M5S 3H7, Canada.,Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, G1V 4G5, Canada
| | | | - Gregory M Chen
- Princess Margaret Cancer Center, University Health Network, Toronto, M5G 2C1, Canada
| | - Levi Waldron
- Graduate School of Public Health and Health Policy, Institute of Implementation Science in Population Health, City University of New York School, New York, 11101, USA.
| | - Benjamin Haibe-Kains
- Princess Margaret Cancer Center, University Health Network, Toronto, M5G 2C1, Canada. .,Department of Medical Biophysics, University of Toronto, Toronto, M5S 3H7, Canada. .,Department of Computer Science, University of Toronto, Toronto, M5T 3A1, Canada. .,Ontario Institute of Cancer Research, Toronto, M5G 0A3, Canada. .,Vector Institute, Toronto, M5G 1M1, Canada.
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6
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Abou-El-Naga A, Shaban A, Ghazy H, Elsaid A, Elshazli R, Settin A. Frequency of BRCA1 (185delAG and 5382insC) and BRCA2 (6174delT) mutations in Egyptian women with breast cancer compared to healthy controls. Meta Gene 2018. [DOI: 10.1016/j.mgene.2017.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
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7
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Singh N, Promkan M, Liu G, Varani J, Chakrabarty S. Role of calcium sensing receptor (CaSR) in tumorigenesis. Best Pract Res Clin Endocrinol Metab 2013; 27:455-63. [PMID: 23856272 DOI: 10.1016/j.beem.2013.04.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The extracellular Ca(2+)-sensing receptor (CaSR) is a robust promoter of differentiation in colonic epithelial cells and functions as a tumor suppressor in colon cancer. CaSR mediates its biologic effects through diverse mechanisms. Loss of CaSR expression activates a myriad of stem cell-like molecular features that drive and sustain the malignant and drug-resistant phenotypes of colon cancer. This CaSR-null phenotype, however, is not irreversible and induction of CaSR expression in CaSR-null cells promotes cell death mechanisms and restores drug sensitivity. The CaSR also functions as a tumor suppressor in breast cancer and promotes cellular sensitivity to cytotoxic drugs. BRCA1 and CaSR functions intersect in breast cancer cells, and CaSR activation can rescue breast cancer cells from the deleterious effect of BRCA1 mutations.
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Affiliation(s)
- Navneet Singh
- Southern Illinois University School of Medicine, Department of Medical Microbiology, Immunology and Cell Biology and Simmons Cancer Institute, Springfield, IL, USA.
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8
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Shimizu Y, Mullins N, Blanchard Z, Elshamy WM. BRCA1/p220 loss triggers BRCA1-IRIS overexpression via mRNA stabilization in breast cancer cells. Oncotarget 2012; 3:299-313. [PMID: 22431556 PMCID: PMC3359886 DOI: 10.18632/oncotarget.462] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
BRCA1/p220-assocaited and triple negative/basal-like (TN/BL) tumors are aggressive and incurable breast cancer diseases that share among other features the no/low BRCA1/p220 expression. Here we show that BRCA1/p220 silencing in normal human mammary epithelial (HME) cells reduces expression of two RNA-destabilizing proteins, namely AUF1 and pCBP2, both proteins bind and destabilize BRCA1-IRIS mRNA. BRCA1-IRIS overexpression in HME cells triggers expression of several TN/BL markers, e.g., cytokeratins 5 and 17, p-cadherin, EGFR and cyclin E as well as expression and activation of the pro-survival proteins; AKT and survivin. BRCA1-IRIS silencing in the TN/BL cell line, SUM149 or restoration of BRCA1/p220 expression in the mutant cell line, HCC1937 reduced expression of TN/BL markers, AKT and survivin and induced cell death. Collectively, we propose that BRCA1/p220 loss of expression or function triggers BRCA1-IRIS overexpression through a post-transcriptional mechanism, which in turn promotes formation of aggressive and invasive breast tumors by inducing expression of TN/BL and survival proteins.
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Affiliation(s)
- Yoshiko Shimizu
- Cancer Institute and Department of Biochemistry, University of Mississippi Medical Center, Jackson, MS, USA
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9
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Cabarcas S, Schramm L. RNA polymerase III transcription in cancer: the BRF2 connection. Mol Cancer 2011; 10:47. [PMID: 21518452 PMCID: PMC3098206 DOI: 10.1186/1476-4598-10-47] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Accepted: 04/25/2011] [Indexed: 12/13/2022] Open
Abstract
RNA polymerase (pol) III transcription is responsible for the transcription of small, untranslated RNAs involved in fundamental metabolic processes such mRNA processing (U6 snRNA) and translation (tRNAs). RNA pol III transcription contributes to the regulation of the biosynthetic capacity of a cell and a direct link exists between cancer cell proliferation and deregulation of RNA pol III transcription. Accurate transcription by RNA pol III requires TFIIIB, a known target of regulation by oncogenes and tumor suppressors. There have been significant advances in our understanding of how TFIIIB-mediated transcription is deregulated in a variety of cancers. Recently, BRF2, a component of TFIIIB required for gene external RNA pol III transcription, was identified as an oncogene in squamous cell carcinomas of the lung through integrative genomic analysis. In this review, we focus on recent advances demonstrating how BRF2-TFIIIB mediated transcription is regulated by tumor suppressors and oncogenes. Additionally, we present novel data further confirming the role of BRF2 as an oncogene, extracted from the Oncomine database, a cancer microarray database containing datasets derived from patient samples, providing evidence that BRF2 has the potential to be used as a biomarker for patients at risk for metastasis. This data further supports the idea that BRF2 may serve as a potential therapeutic target in a variety of cancers.
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Affiliation(s)
- Stephanie Cabarcas
- National Cancer Institute, Laboratory of Cancer Prevention, Cancer Stem Cell Section, 1050 Boyles Street, Building 560, Room 21-81, Frederick, MD 21702, USA
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10
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BRCA1 suppresses the expression of survivin and promotes sensitivity to paclitaxel through the calcium sensing receptor (CaSR) in human breast cancer cells. Cell Calcium 2011; 49:79-88. [DOI: 10.1016/j.ceca.2011.01.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 01/07/2011] [Accepted: 01/12/2011] [Indexed: 01/09/2023]
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11
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Wang YQ, Zhang JR, Li SD, He YY, Yang YX, Liu XL, Wan XP. Aberrant methylation of breast and ovarian cancer susceptibility gene 1 in chemosensitive human ovarian cancer cells does not involve the phosphatidylinositol 3'-kinase-Akt pathway. Cancer Sci 2010; 101:1618-23. [PMID: 20487263 PMCID: PMC11158593 DOI: 10.1111/j.1349-7006.2010.01568.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Methylation is an important silencing mechanism of breast and ovarian cancer susceptibility gene 1 (BRCA1) expression in sporadic ovarian cancer. However, the role of BRCA1 methylation in chemotherapy in sporadic ovarian cancer and the related pathways have not been understood completely. This study has determined the roles of BRCA1 hypermethylation in chemotherapy of sporadic ovarian cancer and its related signaling pathways. We used bisulfite sequencing, real-time polymerase chain reaction, and western blotting to check the methylation state and expression levels of BRCA1 of the following cell lines: platinum-sensitive human ovarian cancer cell line COC1, platinum-resistant cell line COC1/DDP, SKOV-3, and 5-Aza-dC treated COC1. The cisplatin sensitivity of ovarian cancer cells was examined by MTS (methyl-thiazol tetrazolium) assay. Tumorigenicity in vivo and DDP-based chemosensitivity were compared among the above cells. Phosphatidylinositol 3'-kinase (PI3K)-Akt pathway activation in ovarian cancer cells was studied by western blotting. The frequency of BRCA1 methylation in the COC1 cell line was higher than in COC1/DDP and SKOV-3 cell lines, whereas the mRNA and protein expression of BRCA1 were lower than in the COC1/DDP and SKOV-3 cell lines. DNA demethylation decreased the chemosensitivity of COC1 cells and partially increased the expression levels of BRCA1. The activation of the PI3K-Akt pathway was low in ovarian cancer cells. Our results indicate that hypermethylation of BRCA1 might play an important role in the chemosensitivity of ovarian cancer, and that the PI3K-Akt pathway is not involved in this response.
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Affiliation(s)
- Yan-Qiu Wang
- Department of Obstetrics and Gynecology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, China
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12
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Promkan M, Liu G, Patmasiriwat P, Chakrabarty S. BRCA1 modulates malignant cell behavior, the expression of survivin and chemosensitivity in human breast cancer cells. Int J Cancer 2009; 125:2820-8. [DOI: 10.1002/ijc.24684] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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13
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Abstract
The regulated degradation of cellular proteins by the ubiquitin-proteasome system impacts a range of vital cellular processes in both normal and cancerous cells. An ubiquitin-activating enzyme (E1), ubiquitin-conjugating enzyme (E2), and ubiquitin ligase (E3) catalyzes the conjugation of the protein ubiquitin to a target protein and, thereby, tags that protein for recognition and destruction by the proteasome. Ubiquitin ligases are particularly interesting because they determine substrate selection. This review examines the role of dysregulated ubiquitin ligase activity in the development and progression of various cancers, and highlights why ubiquitin ligases have emerged as extremely attractive targets for therapeutic intervention in a number of human malignancies.
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Affiliation(s)
- Kim Newton
- Department of Physiological Chemistry, Genentech, Inc., South San Francisco, California 94110, USA
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14
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Veras I, Rosen EM, Schramm L. Inhibition of RNA polymerase III transcription by BRCA1. J Mol Biol 2009; 387:523-31. [PMID: 19361418 DOI: 10.1016/j.jmb.2009.02.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Revised: 01/31/2009] [Accepted: 02/03/2009] [Indexed: 12/20/2022]
Abstract
RNA polymerase III (RNA pol III) transcribes structural RNAs involved in RNA processing (U6 snRNA) and translation (tRNA), thereby regulating the growth rate of cells. Proper initiation by RNA pol III requires the transcription factor TFIIIB. Gene-external U6 snRNA transcription requires TFIIIB consisting of Bdp1, TBP, and Brf2. Transcription from the gene-internal tRNA promoter requires TFIIIB composed of Bdp1, TBP, and Brf1. TFIIIB is a target of tumor suppressors, including PTEN, ARF, p53, and RB, and RB-related pocket proteins. Breast cancer susceptibility gene 1 (BRCA1) tumor suppressor plays a role in DNA repair, cell cycle regulation, apoptosis, genome integrity, and ubiquitination. BRCA1 has a conserved amino-terminal RING domain, an activation domain 1 (AD1), and an acidic carboxyl-terminal domain (BRCA1 C-terminal region). In Saccharomyces cerevisiae, TFIIB interacts with the BRCA1 C-terminal region domain of Fcp1p, an RNA polymerase II phosphatase. The TFIIIB subunits Brf1 and Brf2 are structurally similar to TFIIB. Hence, we hypothesize that RNA pol III may be regulated by BRCA1 via the TFIIB family members Brf1 and Brf2. Here we report that: (1) BRCA1 inhibits both VAI (tRNA) and U6 snRNA RNA pol III transcription; (2) the AD1 of BRCA1 is responsible for inhibition of U6 snRNA transcription, whereas the RING domain and AD1 of BRCA1 are required for VAI transcription inhibition; and (3) overexpression of Brf1 and Brf2 alleviates inhibition of U6 snRNA and VAI transcription by BRCA1. Taken together, these data suggest that BRCA1 is a general repressor of RNA pol III transcription.
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Affiliation(s)
- Ingrid Veras
- Department of Biological Sciences, St John's University, Queens, NY 11439, USA
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15
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Affiliation(s)
- Sung-Won Kim
- Department of Surgery, Seoul National University College of Medicine, Korea.
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16
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Anczuków O, Buisson M, Salles MJ, Triboulet S, Longy M, Lidereau R, Sinilnikova OM, Mazoyer S. Unclassified variants identified in BRCA1 exon 11: Consequences on splicing. Genes Chromosomes Cancer 2008; 47:418-26. [PMID: 18273839 DOI: 10.1002/gcc.20546] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Numerous mutations identified in breast/ovarian cancer families occur in splice sites of the BRCA1 gene. Splicing can also be disrupted by mutations occurring in exonic splicing enhancer (ESE) sequences. It is important to identify those mutations among the large number of nontruncating sequence variants that are identified during molecular diagnosis, as this could help to classify some of them as cancer predisposing. Several software programs have been designed to identify ESEs and can therefore be used to predict the outcome of genetic variation. However, it is not known whether these predictions are relevant in the case of BRCA1 exon 11 (3.4 kb). In this study, we assessed the consequences on splicing of 108 exon 11 variants identified in French breast/ovarian cancer families, most of them predicted to alter putative ESEs, and of nine variants located in the exon 11 alternative donor splice site. We employed a BRCA1 minigene consisting of exon 10 to 12, into which we introduced separately each of the variants to be tested. RNA was analyzed by RT-PCR after transient transfection of the resulting minigenes. None of the tested variants was found to dramatically alter splicing through disruption of an ESE. However, we identified several variants in the alternative donor splice site that are likely to be of biological significance as they appear to favor the expression of BRCA1-Delta11b over that of the full-length transcript. The results of this study will be of value to classify BRCA1 exon 11 variants of unknown significance. This article contains Supplementary Material available at http://www.interscience.wiley.com/jpages/1045-2257/suppmat.
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Affiliation(s)
- Olga Anczuków
- Laboratoire de Génétique Moléculaire, Signalisation et Cancer UMR5201 CNRS, Lyon, France
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17
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Buisson M, Anczuków O, Zetoune AB, Ware MD, Mazoyer S. The 185delAG mutation (c.68_69delAG) in the BRCA1 gene triggers translation reinitiation at a downstream AUG codon. Hum Mutat 2006; 27:1024-9. [PMID: 16941470 DOI: 10.1002/humu.20384] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The 185delAG mutation (c.68_69delAG; ter39) in the BRCA1 gene is a founder Jewish Ashkenazi mutation that is carried by 1% of this population and has been identified in thousands of breast or ovarian cancer patients. We have previously described that transcripts bearing this mutation, as well as transcripts bearing the 188del11 mutation (c.71_81del; ter36), are not degraded by nonsense-mediated mRNA decay (NMD), contrary to our observations of other truncating mutations that introduce premature termination codons (PTCs) farther downstream in the coding sequence [Perrin-Vidoz et al., 2002]. To test the hypothesis that these two mutations fail to trigger NMD because of translation reinitiation, we have constructed BRCA1 minigenes and studied their protein expression after transient expression in HeLa cells. We show here that in the presence of a (PTC) at position 36 or 39, translation reinitiation occurs in the BRCA1 minigenes at position 128.
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Affiliation(s)
- Monique Buisson
- Laboratoire de Génétique Moléculaire, Signalisation et Cancer Unité Mixte de Recherche 5201 Centre National de la Recherche Scientifique, Université Claude Bernard Lyon I, Lyon, France
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