51
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Hong R, Zhang W, Xia X, Zhang K, Wang Y, Wu M, Fan J, Li J, Xia W, Xu F, Chen J, Wang S, Zhan Q. Preventing BRCA1/ZBRK1 repressor complex binding to the GOT2 promoter results in accelerated aspartate biosynthesis and promotion of cell proliferation. Mol Oncol 2019; 13:959-977. [PMID: 30714292 PMCID: PMC6441895 DOI: 10.1002/1878-0261.12466] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 12/27/2018] [Accepted: 01/24/2019] [Indexed: 02/06/2023] Open
Abstract
Breast cancer susceptibility gene 1 (BRCA1) has been implicated in modulating metabolism via transcriptional regulation. However, direct metabolic targets of BRCA1 and the underlying regulatory mechanisms are still unknown. Here, we identified several metabolic genes, including the gene which encodes glutamate‐oxaloacetate transaminase 2 (GOT2), a key enzyme for aspartate biosynthesis, which are repressed by BRCA1. We report that BRCA1 forms a co‐repressor complex with ZBRK1 that coordinately represses GOT2 expression via a ZBRK1 recognition element in the promoter of GOT2. Impairment of this complex results in upregulation of GOT2, which in turn increases aspartate and alpha ketoglutarate production, leading to rapid cell proliferation of breast cancer cells. Importantly, we found that GOT2 can serve as an independent prognostic factor for overall survival and disease‐free survival of patients with breast cancer, especially triple‐negative breast cancer. Interestingly, we also demonstrated that GOT2 overexpression sensitized breast cancer cells to methotrexate, suggesting a promising precision therapeutic strategy for breast cancer treatment. In summary, our findings reveal that BRCA1 modulates aspartate biosynthesis through transcriptional repression of GOT2, and provides a biological basis for treatment choices in breast cancer.
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Affiliation(s)
- Ruoxi Hong
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Weimin Zhang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, China
| | - Xi Xia
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China.,Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety and Beijing Laboratory for Food Quality and Safety, China Agricultural University, Beijing, China
| | - Kai Zhang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Yan Wang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, China
| | - Mengjiao Wu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, China
| | - Jiawen Fan
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, China
| | - Jinting Li
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, China
| | - Wen Xia
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Fei Xu
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Jie Chen
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, China
| | - Shusen Wang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Qimin Zhan
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, China.,State Key Laboratory of Molecular Oncology, National Cancer Institute and Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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Tarpey MD, Valencia AP, Jackson KC, Amorese AJ, Balestrieri NP, Renegar RH, Pratt SJP, Ryan TE, McClung JM, Lovering RM, Spangenburg EE. Induced in vivo knockdown of the Brca1 gene in skeletal muscle results in skeletal muscle weakness. J Physiol 2019; 597:869-887. [PMID: 30556208 PMCID: PMC6355718 DOI: 10.1113/jp276863] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 11/19/2018] [Indexed: 12/22/2022] Open
Abstract
KEY POINTS Breast cancer 1 early onset gene codes for the DNA repair enzyme, breast cancer type 1 susceptibility protein (BRCA1). The gene is prone to mutations that cause a loss of protein function. BRCA1/Brca1 has recently been found to regulate several cellular pathways beyond DNA repair and is expressed in skeletal muscle. Skeletal muscle specific knockout of Brca1 in mice caused a loss of muscle quality, identifiable by reductions in muscle force production and mitochondrial respiratory capacity. Loss of muscle quality was associated with a shift in muscle phenotype and an accumulation of mitochondrial DNA mutations. These results demonstrate that BRCA1 is necessary for skeletal muscle function and that increased mitochondrial DNA mutations may represent a potential underlying mechanism. ABSTRACT Recent evidence suggests that the breast cancer 1 early onset gene (BRCA1) influences numerous peripheral tissues, including skeletal muscle. The present study aimed to determine whether induced-loss of the breast cancer type 1 susceptibility protein (Brca1) alters skeletal muscle function. We induced genetic ablation of exon 11 in the Brca1 gene specifically in the skeletal muscle of adult mice to generate skeletal muscle-specific Brca1 homozygote knockout (Brca1KOsmi ) mice. Brca1KOsmi exhibited kyphosis and decreased maximal isometric force in limb muscles compared to age-matched wild-type mice. Brca1KOsmi skeletal muscle shifted toward an oxidative muscle fibre type and, in parallel, increased myofibre size and reduced capillary numbers. Unexpectedly, myofibre bundle mitochondrial respiration was reduced, whereas contraction-induced lactate production was elevated in Brca1KOsmi muscle. Brca1KOsmi mice accumulated mitochondrial DNA mutations and exhibited an altered mitochondrial morphology characterized by distorted and enlarged mitochondria, and these were more susceptible to swelling. In summary, skeletal muscle-specific loss of Brca1 leads to a myopathy and mitochondriopathy characterized by reductions in skeletal muscle quality and a consequent kyphosis. Given the substantial impact of BRCA1 mutations on cancer development risk in humans, a parallel loss of BRCA1 function in patient skeletal muscle cells would potentially result in implications for human health.
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Affiliation(s)
- Michael D. Tarpey
- Department of PhysiologyBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
| | - Ana P. Valencia
- School of Public HealthDepartment of KinesiologyUniversity of MarylandCollege ParkMDUSA
| | - Kathryn C. Jackson
- School of Public HealthDepartment of KinesiologyUniversity of MarylandCollege ParkMDUSA
| | - Adam J. Amorese
- Department of PhysiologyBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
| | | | - Randall H. Renegar
- Department of Anatomy and Cell BiologyBrody School of Medicine at East Carolina UniversityGreenvilleNCUSA
| | - Stephen J. P. Pratt
- School of MedicineDepartment of OrthopedicsUniversity of MarylandBaltimoreMDUSA
| | - Terence E. Ryan
- Department of PhysiologyBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
| | - Joseph M. McClung
- Department of PhysiologyBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
- East Carolina Diabetes and Obesity InstituteBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
| | - Richard M. Lovering
- School of MedicineDepartment of OrthopedicsUniversity of MarylandBaltimoreMDUSA
| | - Espen E. Spangenburg
- Department of PhysiologyBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
- East Carolina Diabetes and Obesity InstituteBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
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Alblihy A, Mesquita KA, Sadiq MT, Madhusudan S. Development and implementation of precision therapies targeting base-excision DNA repair in BRCA1-associated tumors. EXPERT REVIEW OF PRECISION MEDICINE AND DRUG DEVELOPMENT 2019. [DOI: 10.1080/23808993.2019.1567266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Adel Alblihy
- Translational Oncology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham, UK
| | - Katia A. Mesquita
- Translational Oncology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham, UK
| | - Maaz T. Sadiq
- Department of Oncology, Nottingham University Hospitals, City Hospital Campus, Nottingham, UK
| | - Srinivasan Madhusudan
- Translational Oncology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham, UK
- Department of Oncology, Nottingham University Hospitals, City Hospital Campus, Nottingham, UK
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54
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Zhang X, Li R. BRCA1-Dependent Transcriptional Regulation: Implication in Tissue-Specific Tumor Suppression. Cancers (Basel) 2018; 10:cancers10120513. [PMID: 30558184 PMCID: PMC6316118 DOI: 10.3390/cancers10120513] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Revised: 11/24/2018] [Accepted: 12/11/2018] [Indexed: 12/11/2022] Open
Abstract
Germ-line mutations in breast cancer susceptibility gene 1 (BRCA1) predominantly predispose women to breast and ovarian cancers. BRCA1 is best known for its functions in maintenance of genomic integrity including repairing DNA double-strand breaks through homologous recombination and suppressing DNA replication stress. However, whether these universally important BRCA1 functions in maintenance of genomic stability are sufficient to account for its tissue-specific tumor-suppressing function remains unclear. Accumulating evidence indicates that there are previously underappreciated roles of BRCA1 in transcriptional regulation and chromatin remodeling. In this review, we discuss the functional significance of interactions between BRCA1 and various transcription factors, its role in epigenetic regulation and chromatin dynamics, and BRCA1-dependent crosstalk between the machineries of transcription and genome integrity. Furthermore, we propose a model of how transcriptional regulation could contribute to tissue-dependent tumor-suppressing function of BRCA1.
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Affiliation(s)
- Xiaowen Zhang
- Department of Biochemistry & Molecular Medicine, School of Medicine & Health Sciences, The George Washington University, Washington, DC 20037, USA.
| | - Rong Li
- Department of Biochemistry & Molecular Medicine, School of Medicine & Health Sciences, The George Washington University, Washington, DC 20037, USA.
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55
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Chen LL, Lin HP, Zhou WJ, He CX, Zhang ZY, Cheng ZL, Song JB, Liu P, Chen XY, Xia YK, Chen XF, Sun RQ, Zhang JY, Sun YP, Song L, Liu BJ, Du RK, Ding C, Lan F, Huang SL, Zhou F, Liu S, Xiong Y, Ye D, Guan KL. SNIP1 Recruits TET2 to Regulate c-MYC Target Genes and Cellular DNA Damage Response. Cell Rep 2018; 25:1485-1500.e4. [PMID: 30404004 PMCID: PMC6317994 DOI: 10.1016/j.celrep.2018.10.028] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Revised: 09/21/2018] [Accepted: 10/04/2018] [Indexed: 12/17/2022] Open
Abstract
The TET2 DNA dioxygenase regulates gene expression by catalyzing demethylation of 5-methylcytosine, thus epigenetically modulating the genome. TET2 does not contain a sequence-specific DNA-binding domain, and how it is recruited to specific genomic sites is not fully understood. Here we carried out a mammalian two-hybrid screen and identified multiple transcriptional regulators potentially interacting with TET2. The SMAD nuclear interacting protein 1 (SNIP1) physically interacts with TET2 and bridges TET2 to bind several transcription factors, including c-MYC. SNIP1 recruits TET2 to the promoters of c-MYC target genes, including those involved in DNA damage response and cell viability. TET2 protects cells from DNA damage-induced apoptosis dependending on SNIP1. Our observations uncover a mechanism for targeting TET2 to specific promoters through a ternary interaction with a co-activator and many sequence-specific DNA-binding factors. This study also reveals a TET2-SNIP1-c-MYC pathway in mediating DNA damage response, thereby connecting epigenetic control to maintenance of genome stability.
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Affiliation(s)
- Lei-Lei Chen
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Huai-Peng Lin
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China; Medical College of Xiamen University, Xiamen 361102, China
| | - Wen-Jie Zhou
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Chen-Xi He
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Zhi-Yong Zhang
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Zhou-Li Cheng
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Jun-Bin Song
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Peng Liu
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Xin-Yu Chen
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Yu-Kun Xia
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Xiu-Fei Chen
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Ren-Qiang Sun
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Jing-Ye Zhang
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Yi-Ping Sun
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Lei Song
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Radiation Medicine, National Center for National Center for Protein Science (The PHOENIX Center), Beijing, China
| | - Bing-Jie Liu
- Fudan University Shanghai Cancer Center, Key Laboratory of Breast Cancer in Shanghai, Innovation Center for Cell Signaling Network, Cancer Institutes, Fudan University, Shanghai, China
| | - Rui-Kai Du
- Fudan University Shanghai Cancer Center, Key Laboratory of Breast Cancer in Shanghai, Innovation Center for Cell Signaling Network, Cancer Institutes, Fudan University, Shanghai, China
| | - Chen Ding
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Radiation Medicine, National Center for National Center for Protein Science (The PHOENIX Center), Beijing, China
| | - Fei Lan
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Sheng-Lin Huang
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Feng Zhou
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Suling Liu
- Fudan University Shanghai Cancer Center, Key Laboratory of Breast Cancer in Shanghai, Innovation Center for Cell Signaling Network, Cancer Institutes, Fudan University, Shanghai, China
| | - Yue Xiong
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China; Department of Biochemistry and Biophysics, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
| | - Dan Ye
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China; Department of General Surgery, Huashan Hospital, Fudan University, Shanghai 200040, China.
| | - Kun-Liang Guan
- Huashan Hospital and Key Laboratory of Medical Epigenetics and Metabolism and Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China; Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA.
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Ganesan S. Tumor Suppressor Tolerance: Reversion Mutations in BRCA1 and BRCA2 and Resistance to PARP Inhibitors and Platinum. JCO Precis Oncol 2018; 2:1-4. [PMID: 35135103 DOI: 10.1200/po.18.00001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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Kim S, Jin H, Seo HR, Lee HJ, Lee YS. Regulating BRCA1 protein stability by cathepsin S-mediated ubiquitin degradation. Cell Death Differ 2018; 26:812-825. [PMID: 30006610 PMCID: PMC6461859 DOI: 10.1038/s41418-018-0153-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 05/25/2018] [Accepted: 06/08/2018] [Indexed: 01/21/2023] Open
Abstract
Cathepsin S (CTSS) is a cysteine protease that is thought to play a role in many physiological and pathological processes including tumor growth, angiogenesis, and metastasis; it has been identified as a radiation response gene. Here, we examined the role of CTSS in regulating the DNA damage response in breast cancer cells. Activating CTSS (producing the cleavage form of the protein) by radiation induced proteolytic degradation of BRCA1, which ultimately suppressed DNA double-strand break repair activity. Depletion of CTSS by RNAi or expression of a mutant type of CTSS enhanced the protein stability of BRCA1 by inhibiting its ubiquitination. CTSS interacted with the BRCT domain of BRCA1 and facilitated ubiquitin-mediated proteolytic degradation of BRCA1, which was tightly associated with decreased BRCA1-mediated DNA repair activity. Treatment with a pharmacological CTSS inhibitor inhibited proteolytic degradation of BRCA1 and restored BRCA1 function. Depletion of CTSS by shRNA delayed tumor growth in a xenograft mouse model, only in the presence of functional BRCA1. Spontaneously uced rat mammary tumors and human breast cancer tissues with high levels of CTSS expression showed low BRCA1 expression. From these data, we suggest that CTSS inhibition is a good strategy for functional restoration of BRCA1 in breast cancers with reduced BRCA1 protein stability.
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Affiliation(s)
- SeoYoung Kim
- Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul, 120-750, Korea
| | - Hee Jin
- Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul, 120-750, Korea
| | - Hang-Rhan Seo
- Functional Morphometry II, Institute Pasteur Korea, Bundang-gu, Seongnam-si, Gyeonggi-do, 463-400, Korea
| | - Hae June Lee
- Division of Basic Radiation Bioscience, Korea Institute of Radiological and Medical Sciences, Seoul, 139-706, Korea
| | - Yun-Sil Lee
- Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul, 120-750, Korea.
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58
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Zhang Y, Ren S, Yuan F, Zhang K, Fan Y, Zheng S, Gao Z, Zhao J, Mu T, Zhao S, Shang A, Li X, Jie Y. miR-135 promotes proliferation and stemness of oesophageal squamous cell carcinoma by targeting RERG. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2018; 46:1210-1219. [PMID: 29961392 DOI: 10.1080/21691401.2018.1483379] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
MicroRNA (miRNA) plays an important role in tumourigenesis and cancer development by regulating oncogenes or tumour suppressor that are implicated in cell cycle, cell mobility and even cell senescence. Due to the resistance to enzymes that could degrade nucleotides, miRNAs have been considered proper for diagnosis and prognosis evaluation of cancer. The present study was designed to investigate miRNA associated with ESCC and identified effective miRNAs, which could serve as biomarker or targets. We first performed miRNA profiling to identify a subset of dysregulated miRNAs in ESCC. miR-135, miR-451 and miR-186 were the most differentially expressed miRNAs. Subsequent RT-PCR validated that miR-135 was upregulated in ESCC cell lines TE2 and TE9, implying the promise as a prognostic and diagnostic marker. The Cox regression analysis suggests the correlation of miR-135 expression and tumour stages. Survival analysis demonstrated metastatic samples largely have higher miR-135 expression. Downregulation of miR-135 suppressed proliferation and invasion of TE2 and TE9 cell lines. Subsequent target prediction combined with functional enrichment analysis identified "Small GTPase superfamily" that are possibly targeted by miR-135, which offers candidates for further investigation. Finally, RERG was identified as a target of miR-135. Downregulation of RERG could inhibit the cell proliferation and sphere formation ability of TE2 and TE9. Taken together, miR-135 was proved to promote tumour development of ESCC, which promises the prospect of using miR-135 as a biomarker indicator in diagnosis and prognosis.
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Affiliation(s)
- Yan Zhang
- a Department of Thoracic Surgery , The First Affiliated Hospital of Zhengzhou University, Zhengzhou University , Zhengzhou , China
| | - Shuang Ren
- b Department of Oncology , The Second Affiliated Hospital of Zhengzhou University, Zhengzhou University , Zhengzhou , China
| | - Fengfeng Yuan
- a Department of Thoracic Surgery , The First Affiliated Hospital of Zhengzhou University, Zhengzhou University , Zhengzhou , China
| | - Kaishang Zhang
- a Department of Thoracic Surgery , The First Affiliated Hospital of Zhengzhou University, Zhengzhou University , Zhengzhou , China
| | - Yingying Fan
- a Department of Thoracic Surgery , The First Affiliated Hospital of Zhengzhou University, Zhengzhou University , Zhengzhou , China
| | - Shaozhong Zheng
- a Department of Thoracic Surgery , The First Affiliated Hospital of Zhengzhou University, Zhengzhou University , Zhengzhou , China
| | - Zhen Gao
- a Department of Thoracic Surgery , The First Affiliated Hospital of Zhengzhou University, Zhengzhou University , Zhengzhou , China
| | - Jia Zhao
- a Department of Thoracic Surgery , The First Affiliated Hospital of Zhengzhou University, Zhengzhou University , Zhengzhou , China
| | - Teng Mu
- a Department of Thoracic Surgery , The First Affiliated Hospital of Zhengzhou University, Zhengzhou University , Zhengzhou , China
| | - Song Zhao
- a Department of Thoracic Surgery , The First Affiliated Hospital of Zhengzhou University, Zhengzhou University , Zhengzhou , China
| | - AnQuan Shang
- c Department of Laboratory Medicine , Tongji Hospital of Tongji University School of Medicine , Shanghai , China
| | - Xiangnan Li
- a Department of Thoracic Surgery , The First Affiliated Hospital of Zhengzhou University, Zhengzhou University , Zhengzhou , China
| | - Ying Jie
- d Department of Clinical Research Center , Xuyi People's Hospital , China
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Dali R, Verginelli F, Pramatarova A, Sladek R, Stifani S. Characterization of a FOXG1:TLE1 transcriptional network in glioblastoma-initiating cells. Mol Oncol 2018; 12:775-787. [PMID: 29316219 PMCID: PMC5983107 DOI: 10.1002/1878-0261.12168] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 12/12/2017] [Accepted: 12/21/2017] [Indexed: 12/11/2022] Open
Abstract
Glioblastoma (GBM) is the most common and deadly malignant brain cancer of glial cell origin, with a median patient survival of less than 20 months. Transcription factors FOXG1 and TLE1 promote GBM propagation by supporting maintenance of brain tumour-initiating cells (BTICs) with stem-like properties. Here, we characterize FOXG1 and TLE1 target genes in GBM patient-derived BTICs using ChIP-Seq and RNA-Seq approaches. These studies identify 150 direct FOXG1 targets, several of which are also TLE1 targets, involved in cell proliferation, differentiation, survival, chemotaxis and angiogenesis. Negative regulators of NOTCH signalling, including CHAC1, are among the transcriptional repression targets of FOXG1:TLE1 complexes, suggesting a crosstalk between FOXG1:TLE1 and NOTCH-mediated pathways in GBM. These results provide previously unavailable insight into the transcriptional programs underlying the tumour-promoting functions of FOXG1:TLE1 in GBM.
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Affiliation(s)
- Rola Dali
- Department of Neurology and NeurosurgeryMontreal Neurological InstituteMcGill UniversityMontrealCanada
- McGill Center for BioinformaticsMcGill UniversityMontrealCanada
| | - Federica Verginelli
- Department of Neurology and NeurosurgeryMontreal Neurological InstituteMcGill UniversityMontrealCanada
- Present address:
Laboratory of Cancer Stem Cell ResearchCandiolo Cancer InstituteFPO‐IRCCSCandioloItaly
| | - Albena Pramatarova
- Departments of Human Genetics and MedicineMcGill UniversityMontrealCanada
| | - Robert Sladek
- Departments of Human Genetics and MedicineMcGill UniversityMontrealCanada
| | - Stefano Stifani
- Department of Neurology and NeurosurgeryMontreal Neurological InstituteMcGill UniversityMontrealCanada
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60
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Gene-Specific Genetic Complementation between Brca1 and Cobra1 During Mouse Mammary Gland Development. Sci Rep 2018; 8:2731. [PMID: 29426838 PMCID: PMC5807304 DOI: 10.1038/s41598-018-21044-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 01/29/2018] [Indexed: 12/22/2022] Open
Abstract
Germ-line mutations in breast cancer susceptibility gene, BRCA1, result in familial predisposition to breast and ovarian cancers. The BRCA1 protein has multiple functional domains that interact with a variety of proteins in multiple cellular processes. Understanding the biological consequences of BRCA1 interactions with its binding partners is important for elucidating its tissue-specific tumor suppression function. The Cofactor of BRCA1 (COBRA1) is a BRCA1-binding protein that, as a component of negative elongation factor (NELF), regulates RNA polymerase II pausing during transcription elongation. We recently identified a genetic interaction between mouse Brca1 and Cobra1 that antagonistically regulates mammary gland development. However, it remains unclear which of the myriad functions of Brca1 are required for its genetic interaction with Cobra1. Here, we show that, unlike deletion of Brca1 exon 11, separation-of-function mutations that abrogate either the E3 ligase activity of its RING domain or the phospho-recognition property of its BRCT domain are not sufficient to rescue the mammary developmental defects in Cobra1 knockout mice. Furthermore, deletion of mouse Palb2, another breast cancer susceptibility gene with functional similarities to BRCA1, does not rescue Cobra1 knockout-associated mammary defects. Thus, the Brca1/Cobra1 genetic interaction is both domain- and gene-specific in the context of mammary gland development.
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Proliferation and ovarian hormone signaling are impaired in normal breast tissues from women with BRCA1 mutations: benefit of a progesterone receptor modulator treatment as a breast cancer preventive strategy in women with inherited BRCA1 mutations. Oncotarget 2018; 7:45317-45330. [PMID: 27246982 PMCID: PMC5216725 DOI: 10.18632/oncotarget.9638] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 05/09/2016] [Indexed: 12/25/2022] Open
Abstract
Women with inherited BRCA1 mutations have an elevated risk (40-80%) for developing breast and ovarian cancers. Reproductive history has been reported to alter this risk, suggesting a relationship between ovarian hormone signaling and BRCA1-related tumor development. BRCA1 interactions with estrogen receptor (ER) and progesterone receptor (PR) signaling were previously described in human breast cancer cell lines and mouse models. However, few studies have examined the effect of ovarian hormone regulation in normal human breast tissues bearing a heterozygous BRCA1 mutation. This study compares the proliferation level (Ki67) and the expression of ER, PR, and of the PR target gene, fatty acid synthase (FASN), in histologically normal breast tissues from women with BRCA1 mutations (BRCA1+/mut, n=23) or without BRCA1 mutations (BRCA1+/+, n=28). BRCA1+/mut tissues showed an increased proliferation and impaired hormone receptor expression with a marked loss of the PR isoform, PR-B. Responses to estradiol and progesterone treatments in BRCA1+/mut and BRCA1+/+ breast tissues were studied in a mouse xenograft model, and showed that PR and FASN expression were deregulated in BRCA1+/mut breast tissues. Progesterone added to estradiol treatment increased the proliferation in a subset of BRCA1+/mut breast tissues. The PR inhibitor, ulipristal acetate (UPA), was able to reverse this aberrant progesterone-induced proliferation. This study suggests that a subset of women with BRCA1 mutations could be candidates for a UPA treatment as a preventive breast cancer strategy.
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Zhao W, Steinfeld JB, Liang F, Chen X, Maranon DG, Ma CJ, Kwon Y, Rao T, Wang W, Chen S, Song X, Deng Y, Jimenez-Sainz J, Lu L, Jensen RB, Xiong Y, Kupfer GM, Wiese C, Greene EC, Sung P. BRCA1-BARD1 promotes RAD51-mediated homologous DNA pairing. Nature 2017; 550:360-365. [PMID: 28976962 PMCID: PMC5800781 DOI: 10.1038/nature24060] [Citation(s) in RCA: 225] [Impact Index Per Article: 32.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 09/08/2017] [Indexed: 12/18/2022]
Abstract
The tumour suppressor complex BRCA1-BARD1 functions in the repair of DNA double-stranded breaks by homologous recombination. During this process, BRCA1-BARD1 facilitates the nucleolytic resection of DNA ends to generate a single-stranded template for the recruitment of another tumour suppressor complex, BRCA2-PALB2, and the recombinase RAD51. Here, by examining purified wild-type and mutant BRCA1-BARD1, we show that both BRCA1 and BARD1 bind DNA and interact with RAD51, and that BRCA1-BARD1 enhances the recombinase activity of RAD51. Mechanistically, BRCA1-BARD1 promotes the assembly of the synaptic complex, an essential intermediate in RAD51-mediated DNA joint formation. We provide evidence that BRCA1 and BARD1 are indispensable for RAD51 stimulation. Notably, BRCA1-BARD1 mutants with weakened RAD51 interactions show compromised DNA joint formation and impaired mediation of homologous recombination and DNA repair in cells. Our results identify a late role of BRCA1-BARD1 in homologous recombination, an attribute of the tumour suppressor complex that could be targeted in cancer therapy.
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Affiliation(s)
- Weixing Zhao
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Justin B. Steinfeld
- Department of Biochemistry & Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Fengshan Liang
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
- Section of Hematology-Oncology, Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520, USA
- Department of Pathology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Xiaoyong Chen
- Section of Hematology-Oncology, Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520, USA
- Department of Pathology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - David G. Maranon
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Chu Jian Ma
- Department of Biochemistry & Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Youngho Kwon
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Timsi Rao
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Weibin Wang
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Sheng Chen
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Xuemei Song
- Yale Center for Analytical Sciences, Yale School of Public Health, New Haven, CT, USA
| | - Yanhong Deng
- Yale Center for Analytical Sciences, Yale School of Public Health, New Haven, CT, USA
| | - Judit Jimenez-Sainz
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Lucy Lu
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Ryan B. Jensen
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Yong Xiong
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Gary M. Kupfer
- Section of Hematology-Oncology, Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520, USA
- Department of Pathology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Claudia Wiese
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Eric C. Greene
- Department of Biochemistry & Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Patrick Sung
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
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63
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Vaidyanathan V, Naidu V, Karunasinghe N, Kao CHJ, Pallati R, Jabed A, Marlow G, Kallingappa P, Ferguson LR. Effect of ageing and single nucleotide polymorphisms associated with the risk of aggressive prostate cancer in a New Zealand population. MOLECULAR BIOSYSTEMS 2017; 13:1967-1980. [PMID: 28783191 DOI: 10.1039/c7mb00203c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Prostate cancer is one of the most significant male health concerns worldwide, and various researchers carrying out molecular diagnostics have indicated that genetic interactions with biological and behavioral factors play an important role in the overall risk and prognosis of this disease. Single nucleotide polymorphisms are increasingly becoming strong biomarker candidates to identify the susceptibility of individuals to prostate cancer. We carried out risk association of different stages of prostate cancer to a number of single nucleotide polymorphisms to identify the susceptible alleles in a New Zealand population and checked the interaction with environmental factors as well. We identified a number of single nucleotide polymorphisms to have associations specifically to the risk of prostate cancer and aggressiveness of the disease, and also certain single nucleotide polymorphisms to be vulnerable to the reported behavioral factors. We have addressed "special" environmental conditions prevalent in New Zealand, which can be used as a model for a bigger worldwide study.
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Affiliation(s)
- Venkatesh Vaidyanathan
- Discipline of Nutrition and Dietetics, FM & HS, University of Auckland, Auckland 1023, New Zealand.
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64
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Abstract
Breast cancer 1 (BRCA1), as a tumor suppressor, exerts an effective influence on protecting DNA integrity to suppress the development of breast cancer (BC). BRCA1 expression is induced in response to DNA-damaging agents such as etoposide. Germline BRCA1 gene mutations are associated with development of hereditary BC. However, besides BRCA-mutated BCs, some sporadic cancers may also exhibit a BRCA-like phenotype, displaying so-called ‘BRCAness’. This common phenotype may respond to similar therapeutic approaches as BRCA-mutated tumors and may thus have important implications for the clinical management of these cancers. In order to determine whether and how etoposide regulates the protein levels of BRCA1 in BC cells, we exposed a panel of five selected cell lines to etoposide, compared the results to untreated control cells, and then stained the cells with the specific, reliable, and reproducible MS110 antibody directed against phosphorylated Ser1423 BRCA1. By evaluating cytoplasmic BRCA1 protein levels, we were able to distinguish three aggressive BC subtypes with BRCAness characteristics. In addition, determination of early and late apoptosis helped to complete the analysis of BRCA1 functions in the DNA damage pathway of aggressive BC. In conclusion, our study suggested that high cytoplasmic BRCA1 protein levels could be considered as a potential predictive marker for response to chemotherapy in both sporadic and hereditary BC. Tumors with either BRCAness phenotype or germline BRCA1 mutation are both aggressive BCs associated with poor prognosis and could both be subjected to targeted therapies against BRCA1-mutated BC in future clinical management strategies.
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65
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Zhang X, Chiang HC, Wang Y, Zhang C, Smith S, Zhao X, Nair SJ, Michalek J, Jatoi I, Lautner M, Oliver B, Wang H, Petit A, Soler T, Brunet J, Mateo F, Angel Pujana M, Poggi E, Chaldekas K, Isaacs C, Peshkin BN, Ochoa O, Chedin F, Theoharis C, Sun LZ, Curiel TJ, Elledge R, Jin VX, Hu Y, Li R. Attenuation of RNA polymerase II pausing mitigates BRCA1-associated R-loop accumulation and tumorigenesis. Nat Commun 2017; 8:15908. [PMID: 28649985 PMCID: PMC5490191 DOI: 10.1038/ncomms15908] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 05/12/2017] [Indexed: 01/08/2023] Open
Abstract
Most BRCA1-associated breast tumours are basal-like yet originate from luminal progenitors. BRCA1 is best known for its functions in double-strand break repair and resolution of DNA replication stress. However, it is unclear whether loss of these ubiquitously important functions fully explains the cell lineage-specific tumorigenesis. In vitro studies implicate BRCA1 in elimination of R-loops, DNA-RNA hybrid structures involved in transcription and genetic instability. Here we show that R-loops accumulate preferentially in breast luminal epithelial cells, not in basal epithelial or stromal cells, of BRCA1 mutation carriers. Furthermore, R-loops are enriched at the 5' end of those genes with promoter-proximal RNA polymerase II (Pol II) pausing. Genetic ablation of Cobra1, which encodes a Pol II-pausing and BRCA1-binding protein, ameliorates R-loop accumulation and reduces tumorigenesis in Brca1-knockout mouse mammary epithelium. Our studies show that Pol II pausing is an important contributor to BRCA1-associated R-loop accumulation and breast cancer development.
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Affiliation(s)
- Xiaowen Zhang
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, 8403 Floyd Curl Drive, San Antonio, Texas 78229, USA
| | - Huai-Chin Chiang
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, 8403 Floyd Curl Drive, San Antonio, Texas 78229, USA
| | - Yao Wang
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, 8403 Floyd Curl Drive, San Antonio, Texas 78229, USA
| | - Chi Zhang
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, 8403 Floyd Curl Drive, San Antonio, Texas 78229, USA
| | - Sabrina Smith
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, 8403 Floyd Curl Drive, San Antonio, Texas 78229, USA
| | - Xiayan Zhao
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, 8403 Floyd Curl Drive, San Antonio, Texas 78229, USA
| | - Sreejith J. Nair
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, 8403 Floyd Curl Drive, San Antonio, Texas 78229, USA
| | - Joel Michalek
- Department of Epidemiology and Biostatistics, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA
| | - Ismail Jatoi
- Department of Surgery, Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA
| | - Meeghan Lautner
- Department of Surgery, Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA
| | - Boyce Oliver
- Department of Surgery, Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA
| | - Howard Wang
- Department of Surgery, Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA
| | - Anna Petit
- Department of Pathology, University Hospital of Bellvitge, Bellvitge Institute for Biomedical Research (IDIBELL), L’Hospitalet del Llobregat, Barcelona 08908, Spain
| | - Teresa Soler
- Department of Pathology, University Hospital of Bellvitge, Bellvitge Institute for Biomedical Research (IDIBELL), L’Hospitalet del Llobregat, Barcelona 08908, Spain
| | - Joan Brunet
- Hereditary Cancer Program, Catalan Institute of Oncology (ICO), Girona Biomedical Research Institute (IDIBGI), Girona 17007, Spain
| | - Francesca Mateo
- Breast Cancer and Systems Biology Lab, Program Against Cancer Therapeutic Resistance (ProCURE), Catalan Institute of Oncology (ICO), Bellvitge Institute for Biomedical Research (IDIBELL), L’Hospitalet del Llobregat, Barcelona 08908, Spain
| | - Miguel Angel Pujana
- Breast Cancer and Systems Biology Lab, Program Against Cancer Therapeutic Resistance (ProCURE), Catalan Institute of Oncology (ICO), Bellvitge Institute for Biomedical Research (IDIBELL), L’Hospitalet del Llobregat, Barcelona 08908, Spain
| | - Elizabeth Poggi
- Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia 20007, USA
| | - Krysta Chaldekas
- Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia 20007, USA
| | - Claudine Isaacs
- Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia 20007, USA
| | - Beth N. Peshkin
- Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia 20007, USA
| | - Oscar Ochoa
- PRMA Plastic Surgery, San Antonio, Texas 78240, USA
| | - Frederic Chedin
- Department of Molecular and Cellular Biology, University of California, Davis, California 95616, USA
| | | | - Lu-Zhe Sun
- Department of Cell Systems and Anatomy, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA
| | - Tyler J. Curiel
- Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA
| | - Richard Elledge
- Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA
| | - Victor X. Jin
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, 8403 Floyd Curl Drive, San Antonio, Texas 78229, USA
| | - Yanfen Hu
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, 8403 Floyd Curl Drive, San Antonio, Texas 78229, USA
| | - Rong Li
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, 8403 Floyd Curl Drive, San Antonio, Texas 78229, USA
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66
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Li Y, Luo K, Yin Y, Wu C, Deng M, Li L, Chen Y, Nowsheen S, Lou Z, Yuan J. USP13 regulates the RAP80-BRCA1 complex dependent DNA damage response. Nat Commun 2017; 8:15752. [PMID: 28569838 PMCID: PMC5461494 DOI: 10.1038/ncomms15752] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 04/25/2017] [Indexed: 12/16/2022] Open
Abstract
BRCA1 regulates multiple cellular pathways that maintain genomic stability including cell cycle checkpoints, DNA repair, protein ubiquitination, chromatin remodelling, transcriptional regulation and apoptosis. Receptor-associated protein 80 (RAP80) helps recruit BRCA1 to double-strand breaks (DSBs) through the scaffold protein CCDC98 (Abraxas) and facilitates DNA damage response (DDR). However, the regulation of RAP80-BRCA1 complex is still unclear. Here we report that a deubiquitinase, USP13, regulates DDR by targeting RAP80. Mechanistically, USP13 is phosphorylated by ATM following DNA damage which, in turn, facilitates its DSB localization. USP13, in turn, deubiquitinates RAP80 and promotes RAP80 recruitment and proper DDR. Depleting or inhibiting USP13 sensitizes ovarian cancer cells to cisplatin and PARP inhibitor (olaparib) while overexpression of USP13 renders ovarian cancer cells resistant to chemotherapy. Overall, we identify USP13 as a regulator of DNA repair and reveal a model in which a phosphorylation-deubiquitination axis dynamically regulates RAP80-BRCA1 complex foci formation and function. RAP80 helps to recruit BRCA1 to double-strand breaks, facilitating DNA damage responses. Here the authors report that phosphorylated USP13 deubiquitinates RAP80 after DNA damage, prompting recruitment to the break site.
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Affiliation(s)
- Yunhui Li
- Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Kuntian Luo
- Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Department of Oncology, Mayo Clinic, Rochester, Minnesota 55905, USA
| | - Yujiao Yin
- Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Chenming Wu
- Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Min Deng
- Department of Oncology, Mayo Clinic, Rochester, Minnesota 55905, USA
| | - Lei Li
- Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Yuping Chen
- Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Somaira Nowsheen
- Medical Scientist Training Program, Mayo Clinic School of Medicine, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, Minnesota 55905, USA
| | - Zhenkun Lou
- Department of Oncology, Mayo Clinic, Rochester, Minnesota 55905, USA
| | - Jian Yuan
- Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Department of Oncology, Mayo Clinic, Rochester, Minnesota 55905, USA
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67
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Kim D, Kim Y, Son N, Kang C, Kim A. Recent omics technologies and their emerging applications for personalised medicine. IET Syst Biol 2017; 11:87-98. [DOI: 10.1049/iet-syb.2016.0016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Affiliation(s)
- Dong‐Hyuk Kim
- School of Life ScienceHandong Global UniversityPohangGyungbuk37554South Korea
| | - Young‐Sook Kim
- School of Life ScienceHandong Global UniversityPohangGyungbuk37554South Korea
| | - Nam‐Il Son
- School of Life ScienceHandong Global UniversityPohangGyungbuk37554South Korea
| | - Chan‐Koo Kang
- School of Life ScienceHandong Global UniversityPohangGyungbuk37554South Korea
| | - Ah‐Ram Kim
- School of Life ScienceHandong Global UniversityPohangGyungbuk37554South Korea
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68
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Liu X, Li H, Shao B, Wu J, Kong W, Song G, Jiang H, Wang J, Wan F. Identification of recurrent BRCA1 mutation and its clinical relevance in Chinese Triple-negative breast cancer cohort. Cancer Med 2017; 6:547-554. [PMID: 28135048 PMCID: PMC5345662 DOI: 10.1002/cam4.1004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 11/04/2016] [Accepted: 12/07/2016] [Indexed: 12/31/2022] Open
Abstract
Triple‐negative breast cancer (TNBC) accounts for 15–20% of all newly diagnosed breast cancers, and is enriched for germline mutation of BRCA. In Asian patients diagnosed with breast cancer, 268 deleterious mutations of BRCA1 and 242 of BRCA2 have been identified so far, including a reported BRCA1 frameshift mutation (rs80350973), apparently found only in Asian people, with a low prevalence of 0.3–1.7% in different breast cancer cohorts. Here, we reported the high prevalence (7.2%) of rs80350973 among 125 Chinese patients with TNBC, which implies its mutational predilection for certain breast cancer subtypes. Although its low prevalence had not indicated any particular clinical significance in previous studies, our results associated rs80350973 mutation with cell checkpoint malfunction, and was found to be more common in TNBC patients with high Ki‐67 indices (P = 0.004). As Ki‐67 overexpression is a predictor of poor prognosis in TNBC, inclusion of this mutation into genetic assessments may improve the clinical management of Chinese patients with TNBC.
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Affiliation(s)
- Xiaoran Liu
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of breast oncology, Peking University Cancer Hospital & Institute, Fucheng Road No.52, Haidian District, Beijing, 100142, China
| | - Huiping Li
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of breast oncology, Peking University Cancer Hospital & Institute, Fucheng Road No.52, Haidian District, Beijing, 100142, China
| | - Bin Shao
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of breast oncology, Peking University Cancer Hospital & Institute, Fucheng Road No.52, Haidian District, Beijing, 100142, China
| | - Jianmin Wu
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of breast oncology, Peking University Cancer Hospital & Institute, Fucheng Road No.52, Haidian District, Beijing, 100142, China
| | - Weiyao Kong
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of breast oncology, Peking University Cancer Hospital & Institute, Fucheng Road No.52, Haidian District, Beijing, 100142, China
| | - Guohong Song
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of breast oncology, Peking University Cancer Hospital & Institute, Fucheng Road No.52, Haidian District, Beijing, 100142, China
| | - Hanfang Jiang
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of breast oncology, Peking University Cancer Hospital & Institute, Fucheng Road No.52, Haidian District, Beijing, 100142, China
| | - Jing Wang
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of breast oncology, Peking University Cancer Hospital & Institute, Fucheng Road No.52, Haidian District, Beijing, 100142, China
| | - Fengling Wan
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of breast oncology, Peking University Cancer Hospital & Institute, Fucheng Road No.52, Haidian District, Beijing, 100142, China
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69
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Afghahi A, Timms KM, Vinayak S, Jensen KC, Kurian AW, Carlson RW, Chang PJ, Schackmann E, Hartman AR, Ford JM, Telli ML. Tumor BRCA1 Reversion Mutation Arising during Neoadjuvant Platinum-Based Chemotherapy in Triple-Negative Breast Cancer Is Associated with Therapy Resistance. Clin Cancer Res 2017; 23:3365-3370. [PMID: 28087643 DOI: 10.1158/1078-0432.ccr-16-2174] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 12/16/2016] [Accepted: 12/23/2016] [Indexed: 01/02/2023]
Abstract
Purpose: In germline BRCA1 or BRCA2 (BRCA1/2) mutation carriers, restoration of tumor BRCA1/2 function by a secondary mutation is recognized as a mechanism of resistance to platinum and PARP inhibitors, primarily in ovarian cancer. We evaluated this mechanism of resistance in newly diagnosed patients with BRCA1/2-mutant breast cancer with poor response to neoadjuvant platinum-based therapy.Experimental Design: PrECOG 0105 was a phase II neoadjuvant study of gemcitabine, carboplatin, and iniparib in patients with stage I-IIIA triple-negative or BRCA1/2 mutation-associated breast cancer (n = 80). All patients underwent comprehensive BRCA1/2 genotyping. For mutation carriers with moderate or extensive residual disease after neoadjuvant therapy, BRCA1/2 status was resequenced in the residual surgical breast tumor tissue.Results: Nineteen patients had a deleterious germline BRCA1/2 mutation, and four had moderate residual disease at surgery. BRCA1/2 sequencing of residual tissue was performed on three patients. These patients had BRCA1 1479delAG, 3374insGA, and W1712X mutations, respectively, with LOH at these loci in the pretreatment tumors. In the first case, a new BRCA1 mutation was detected in the residual disease. This resulted in a 14-amino acid deletion and restoration of the BRCA1 reading frame. A local relapse biopsy 4 months later revealed the identical reversion mutation, and the patient subsequently died from metastatic breast cancer.Conclusions: We report a BRCA1 reversion mutation in a patient newly diagnosed with triple-negative breast cancer that developed over 18 weeks of platinum-based neoadjuvant therapy. This was associated with poor therapy response, early relapse, and death. Clin Cancer Res; 23(13); 3365-70. ©2017 AACR.
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Affiliation(s)
- Anosheh Afghahi
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado
| | | | - Shaveta Vinayak
- Department of Medicine, University, Hospitals Case Medical Center, Cleveland, Ohio
| | - Kristin C Jensen
- Department of Medicine, Stanford, University School of Medicine, Stanford, California
| | - Allison W Kurian
- Department of Medicine, Stanford, University School of Medicine, Stanford, California
| | - Robert W Carlson
- National Comprehensive Cancer Network, Fort Washington, Pennsylvania
| | - Pei-Jen Chang
- Department of Medicine, Stanford, University School of Medicine, Stanford, California
| | - Elizabeth Schackmann
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | | | - James M Ford
- Department of Medicine, Stanford, University School of Medicine, Stanford, California
| | - Melinda L Telli
- Department of Medicine, Stanford, University School of Medicine, Stanford, California.
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70
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BRCAness as a Biomarker for Predicting Prognosis and Response to Anthracycline-Based Adjuvant Chemotherapy for Patients with Triple-Negative Breast Cancer. PLoS One 2016; 11:e0167016. [PMID: 27977696 PMCID: PMC5158199 DOI: 10.1371/journal.pone.0167016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 11/07/2016] [Indexed: 12/31/2022] Open
Abstract
Background Triple-negative breast cancer (TNBC) is a heterogeneous tumor that encompasses many different subclasses of the disease. In this study, we assessed BRCAness, defined as the shared characteristics between sporadic and BRCA1-mutated tumors, in a large cohort of TNBC cases. Methods The BRCAness of 262 patients with primary TNBCs resected between January 2004 and December 2014 was determined through the isolation of DNA from tumor tissue. Classification of BRCAness was performed using multiple ligation-dependent probe amplification (MLPA). The tumor subtypes were determined immunohistochemically using resected specimens. Results Of the 262 TNBCs, the results of the MLPA assays showed that 174 (66.4%) tumors had BRCAness. Patients with BRCAness tumors were younger than patients with non-BRCAness tumors (P = 0.003). There was no significant difference between the two groups regarding their pathological stages. The BRCAness group had a significantly shorter recurrence-free survival (RFS) compared with the non-BRCAness group (P = 0.04) and had a shorter overall survival (OS) although this did not reach statistical significance. Adjuvant treatments with anthracycline-based regimens provided significantly greater benefits to the BRCAness group (P = 0.003 for RFS, and P = 0.03 for OS). Multivariate Cox proportional hazard model analysis showed that BRCAness was an independent negative prognostic factor, and the anthracycline-based adjuvant chemotherapy was an independent positive prognostic factor for both RFS and OS in TNBC. Conclusions The 66.4% patients of TNBCs showed BRCAness. BRCAness is essential as a biomarker in the subclassification of TNBCs and might be of use for predicting their prognosis. Furthermore, this biomarker might be a predictive factor for the effectiveness of anthracycline-based adjuvant chemotherapy for patients with TNBCs.
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Sedic M, Kuperwasser C. BRCA1-hapoinsufficiency: Unraveling the molecular and cellular basis for tissue-specific cancer. Cell Cycle 2016; 15:621-7. [PMID: 26822887 DOI: 10.1080/15384101.2016.1141841] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Over the past 20 years tremendous progress has been made in understanding the function of BRCA1 gene products. Yet one question still remains: why is mutation of BRCA1 typically associated with preferential development of breast and ovarian cancers and not tumors in other tissues? Here we discuss recent evidence documenting the effect of BRCA1-haploinsufficiency in different cells and tissues and synthesize a model for how mutations in a single BRCA1 allele in human cells might preferentially confer increased cancer risk in breast epithelial cells.
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Affiliation(s)
- Maja Sedic
- a Department of Developmental , Chemical, and Molecular Biology, Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine , Boston , MA , USA.,b Raymond and Beverly Sackler Convergence Laboratory, Tufts University School of Medicine , Boston , MA , USA.,c Molecular Oncology Research Institute, Tufts Medical Center , Boston , MA , USA
| | - Charlotte Kuperwasser
- a Department of Developmental , Chemical, and Molecular Biology, Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine , Boston , MA , USA.,b Raymond and Beverly Sackler Convergence Laboratory, Tufts University School of Medicine , Boston , MA , USA.,c Molecular Oncology Research Institute, Tufts Medical Center , Boston , MA , USA
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72
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Foulkes WD, Sugano K. BRCA2: a grown-up cancer susceptibility gene. Endocr Relat Cancer 2016; 23:E1-3. [PMID: 27650115 DOI: 10.1530/erc-16-0354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 08/12/2016] [Indexed: 11/08/2022]
Affiliation(s)
- William D Foulkes
- Departments of Human GeneticsMedicine and Oncology, McGill University, Montreal, Quebec, Canada
| | - Kokichi Sugano
- Oncogene Research Unit/Cancer Prevention UnitTochigi Cancer Center Research Institute, Tochigi, Japan
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Kim SJ, Zuchniak A, Sohn KJ, Lubinski J, Demsky R, Eisen A, Akbari MR, Kim YI, Narod SA, Kotsopoulos J. Plasma folate, vitamin B-6, and vitamin B-12 and breast cancer risk in BRCA1- and BRCA2-mutation carriers: a prospective study. Am J Clin Nutr 2016; 104:671-7. [PMID: 27465373 DOI: 10.3945/ajcn.116.133470] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 06/15/2016] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND B vitamins [vitamins B-6, B-9 (folate), and B-12] play important roles in nucleotide biosynthesis and biological methylation reactions, aberrancies of which have all been implicated in carcinogenesis. In the general population, evidence has suggested that high circulating folate and folic acid (synthetic form of folate) supplement use may increase breast cancer risk, but the role of folate in BRCA-associated breast cancer is not clear. OBJECTIVE We prospectively evaluated the relation between plasma folate, pyridoxal 5'-phosphate (PLP; the biologically active form of vitamin B-6), and vitamin B-12 and breast cancer risk in women with a BRCA1/2 mutation. DESIGN Baseline blood samples and biennial follow-up questionnaires were available for 164 BRCA1/2-mutation carriers with no previous history of cancer other than nonmelanoma skin cancer. Plasma folate, PLP, and vitamin B-12 concentrations were categorized dichotomously as high compared with low based on the upper 25% and the lower 75% of distribution, respectively. Cox proportional hazards were used to estimate the HR and 95% CI for the association between plasma biomarkers of each B vitamin and incident breast cancer. RESULTS Over a mean follow-up of 6.3 y, 20 incident primary invasive breast cancers were observed. Women with high plasma folate concentrations (>24.4 ng/mL) were associated with significantly increased breast cancer risk (HR: 3.20; 95% CI: 1.03, 9.92; P = 0.04, P-trend across quintiles = 0.07) compared with that of women with low plasma folate concentrations (≤24.4 ng/mL). Plasma PLP and vitamin B-12 concentrations were not associated with breast cancer risk. CONCLUSIONS Our data suggest that elevated plasma folate concentrations may be associated with increased risk of breast cancer in women with a BRCA1/2 mutation. Additional studies with a larger sample size and longer follow-up periods are warranted to clarify the relation between folate status and breast cancer risk in high-risk women.
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Affiliation(s)
- Shana J Kim
- Departments of Nutritional Sciences, Women's College Research Institute, Women's College Hospital, Toronto, Canada
| | - Anna Zuchniak
- Departments of Nutritional Sciences, Keenan Research Centre for Biomedical Science of St. Michael's Hospital and
| | - Kyoung-Jin Sohn
- Medicine, and Keenan Research Centre for Biomedical Science of St. Michael's Hospital and
| | - Jan Lubinski
- Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland
| | - Rochelle Demsky
- Molecular Genetics and Department of Gynecologic Oncology, Princess Margaret Cancer Center, University Health Network, Toronto, Canada; and
| | - Andrea Eisen
- Toronto-Sunnybrook Regional Cancer Center, Toronto, Canada
| | - Mohammad R Akbari
- Dalla Lana School of Public Health, University of Toronto, Toronto, Canada; Women's College Research Institute, Women's College Hospital, Toronto, Canada
| | - Young-In Kim
- Departments of Nutritional Sciences, Medicine, and Keenan Research Centre for Biomedical Science of St. Michael's Hospital and Division of Gastroenterology, St. Michael's Hospital, Toronto, Canada
| | - Steven A Narod
- Departments of Nutritional Sciences, Medicine, and Dalla Lana School of Public Health, University of Toronto, Toronto, Canada; Women's College Research Institute, Women's College Hospital, Toronto, Canada
| | - Joanne Kotsopoulos
- Departments of Nutritional Sciences, Dalla Lana School of Public Health, University of Toronto, Toronto, Canada; Women's College Research Institute, Women's College Hospital, Toronto, Canada;
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74
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Telli ML, Timms KM, Reid J, Hennessy B, Mills GB, Jensen KC, Szallasi Z, Barry WT, Winer EP, Tung NM, Isakoff SJ, Ryan PD, Greene-Colozzi A, Gutin A, Sangale Z, Iliev D, Neff C, Abkevich V, Jones JT, Lanchbury JS, Hartman AR, Garber JE, Ford JM, Silver DP, Richardson AL. Homologous Recombination Deficiency (HRD) Score Predicts Response to Platinum-Containing Neoadjuvant Chemotherapy in Patients with Triple-Negative Breast Cancer. Clin Cancer Res 2016. [PMID: 26957554 DOI: 10.1158/1078-0432.ccr-15-2477] [] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE BRCA1/2-mutated and some sporadic triple-negative breast cancers (TNBC) have DNA repair defects and are sensitive to DNA-damaging therapeutics. Recently, three independent DNA-based measures of genomic instability were developed on the basis of loss of heterozygosity (LOH), telomeric allelic imbalance (TAI), and large-scale state transitions (LST). EXPERIMENTAL DESIGN We assessed a combined homologous recombination deficiency (HRD) score, an unweighted sum of LOH, TAI, and LST scores, in three neoadjuvant TNBC trials of platinum-containing therapy. We then tested the association of HR deficiency, defined as HRD score ≥42 or BRCA1/2 mutation, with response to platinum-based therapy. RESULTS In a trial of neoadjuvant platinum, gemcitabine, and iniparib, HR deficiency predicted residual cancer burden score of 0 or I (RCB 0/I) and pathologic complete response (pCR; OR = 4.96, P = 0.0036; OR = 6.52, P = 0.0058). HR deficiency remained a significant predictor of RCB 0/I when adjusted for clinical variables (OR = 5.86, P = 0.012). In two other trials of neoadjuvant cisplatin therapy, HR deficiency predicted RCB 0/I and pCR (OR = 10.18, P = 0.0011; OR = 17.00, P = 0.0066). In a multivariable model of RCB 0/I, HR deficiency retained significance when clinical variables were included (OR = 12.08, P = 0.0017). When restricted to BRCA1/2 nonmutated tumors, response was higher in patients with high HRD scores: RCB 0/I P = 0.062, pCR P = 0.063 in the neoadjuvant platinum, gemcitabine, and iniparib trial; RCB 0/I P = 0.0039, pCR P = 0.018 in the neoadjuvant cisplatin trials. CONCLUSIONS HR deficiency identifies TNBC tumors, including BRCA1/2 nonmutated tumors more likely to respond to platinum-containing therapy. Clin Cancer Res; 22(15); 3764-73. ©2016 AACR.
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Affiliation(s)
- Melinda L Telli
- Stanford University School of Medicine, Stanford, California
| | | | - Julia Reid
- Myriad Genetics Inc., Salt Lake City, Utah
| | - Bryan Hennessy
- University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Gordon B Mills
- University of Texas MD Anderson Cancer Center, Houston, Texas
| | | | - Zoltan Szallasi
- Denmark Technical University, Lyngby, Denmark. Children's Hospital Boston, Boston, Massachusetts. Harvard Medical School, Boston, Massachusetts
| | - William T Barry
- Harvard Medical School, Boston, Massachusetts. Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Eric P Winer
- Harvard Medical School, Boston, Massachusetts. Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Nadine M Tung
- Harvard Medical School, Boston, Massachusetts. Beth Israel Deaconess Medical Center, Boston, Massachusetts
| | - Steven J Isakoff
- Harvard Medical School, Boston, Massachusetts. Massachusetts General Hospital, Boston, Massachusetts
| | - Paula D Ryan
- Massachusetts General Hospital, Boston, Massachusetts
| | | | | | | | | | - Chris Neff
- Myriad Genetics Inc., Salt Lake City, Utah
| | | | | | | | | | - Judy E Garber
- Harvard Medical School, Boston, Massachusetts. Dana-Farber Cancer Institute, Boston, Massachusetts
| | - James M Ford
- Stanford University School of Medicine, Stanford, California
| | - Daniel P Silver
- Harvard Medical School, Boston, Massachusetts. Dana-Farber Cancer Institute, Boston, Massachusetts.
| | - Andrea L Richardson
- Harvard Medical School, Boston, Massachusetts. Dana-Farber Cancer Institute, Boston, Massachusetts. Brigham and Women's Hospital, Boston, Massachusetts
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75
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Huertas P, Cruz-García A. Speed matters: How subtle changes in DNA end resection rate affect repair. Mol Cell Oncol 2016; 2:e982964. [PMID: 27308460 PMCID: PMC4905430 DOI: 10.4161/23723556.2014.982964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 10/29/2014] [Accepted: 10/29/2014] [Indexed: 11/29/2022]
Abstract
The contribution of BRCA1 (breast cancer 1) to the repair of broken DNA is well established, but its real role at the molecular level is less well understood. By developing a new high-resolution, single-molecule technique, we have now shown that BRCA1 accelerates the processing of DNA breaks that subsequently engage in homologous recombination.
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Affiliation(s)
- Pablo Huertas
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER); Sevilla, Spain; Departamento de Genética; Universidad de Sevilla; Sevilla, Spain
| | - Andrés Cruz-García
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER); Sevilla, Spain; Departamento de Genética; Universidad de Sevilla; Sevilla, Spain
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76
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Zheng J, Qin W, Jiao D, Ren J, Wei M, Shi S, Xi W, Wang H, Yang AG, Huan Y, Wen W. Knockdown of COUP-TFII inhibits cell proliferation and induces apoptosis through upregulating BRCA1 in renal cell carcinoma cells. Int J Cancer 2016; 139:1574-85. [PMID: 27193872 DOI: 10.1002/ijc.30193] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Accepted: 04/25/2016] [Indexed: 12/30/2022]
Affiliation(s)
- Jia Zheng
- Department of Urology; Tangdu Hospital, Fourth Military Medical University; Xi'an China
- Department of Oncology; the First Affiliated Hospital of Zhengzhou University; Zhengzhou China
| | - Weijun Qin
- Department of Urology; Xijing Hospital, Fourth Military Medical University; Xi'an China
| | - Dian Jiao
- Department of Urology; Tangdu Hospital, Fourth Military Medical University; Xi'an China
| | - Jing Ren
- Department of Radiology; Xijing Hospital, Fourth Military Medical University; Xi'an China
| | - Ming Wei
- Department of Urology; Tangdu Hospital, Fourth Military Medical University; Xi'an China
| | - Shengjia Shi
- State Key Laboratory of Cancer Biology, Department of Immunology; Fourth Military Medical University; Xi'an China
| | - Wenjin Xi
- State Key Laboratory of Cancer Biology, Department of Immunology; Fourth Military Medical University; Xi'an China
| | - He Wang
- Department of Urology; Tangdu Hospital, Fourth Military Medical University; Xi'an China
| | - An-Gang Yang
- State Key Laboratory of Cancer Biology, Department of Immunology; Fourth Military Medical University; Xi'an China
| | - Yi Huan
- Department of Radiology; Xijing Hospital, Fourth Military Medical University; Xi'an China
| | - Weihong Wen
- State Key Laboratory of Cancer Biology, Department of Immunology; Fourth Military Medical University; Xi'an China
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77
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Telli ML, Timms KM, Reid J, Hennessy B, Mills GB, Jensen KC, Szallasi Z, Barry WT, Winer EP, Tung NM, Isakoff SJ, Ryan PD, Greene-Colozzi A, Gutin A, Sangale Z, Iliev D, Neff C, Abkevich V, Jones JT, Lanchbury JS, Hartman AR, Garber JE, Ford JM, Silver DP, Richardson AL. Homologous Recombination Deficiency (HRD) Score Predicts Response to Platinum-Containing Neoadjuvant Chemotherapy in Patients with Triple-Negative Breast Cancer. Clin Cancer Res 2016; 22:3764-73. [PMID: 26957554 DOI: 10.1158/1078-0432.ccr-15-2477] [Citation(s) in RCA: 664] [Impact Index Per Article: 83.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 02/09/2016] [Indexed: 12/15/2022]
Abstract
PURPOSE BRCA1/2-mutated and some sporadic triple-negative breast cancers (TNBC) have DNA repair defects and are sensitive to DNA-damaging therapeutics. Recently, three independent DNA-based measures of genomic instability were developed on the basis of loss of heterozygosity (LOH), telomeric allelic imbalance (TAI), and large-scale state transitions (LST). EXPERIMENTAL DESIGN We assessed a combined homologous recombination deficiency (HRD) score, an unweighted sum of LOH, TAI, and LST scores, in three neoadjuvant TNBC trials of platinum-containing therapy. We then tested the association of HR deficiency, defined as HRD score ≥42 or BRCA1/2 mutation, with response to platinum-based therapy. RESULTS In a trial of neoadjuvant platinum, gemcitabine, and iniparib, HR deficiency predicted residual cancer burden score of 0 or I (RCB 0/I) and pathologic complete response (pCR; OR = 4.96, P = 0.0036; OR = 6.52, P = 0.0058). HR deficiency remained a significant predictor of RCB 0/I when adjusted for clinical variables (OR = 5.86, P = 0.012). In two other trials of neoadjuvant cisplatin therapy, HR deficiency predicted RCB 0/I and pCR (OR = 10.18, P = 0.0011; OR = 17.00, P = 0.0066). In a multivariable model of RCB 0/I, HR deficiency retained significance when clinical variables were included (OR = 12.08, P = 0.0017). When restricted to BRCA1/2 nonmutated tumors, response was higher in patients with high HRD scores: RCB 0/I P = 0.062, pCR P = 0.063 in the neoadjuvant platinum, gemcitabine, and iniparib trial; RCB 0/I P = 0.0039, pCR P = 0.018 in the neoadjuvant cisplatin trials. CONCLUSIONS HR deficiency identifies TNBC tumors, including BRCA1/2 nonmutated tumors more likely to respond to platinum-containing therapy. Clin Cancer Res; 22(15); 3764-73. ©2016 AACR.
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Affiliation(s)
- Melinda L Telli
- Stanford University School of Medicine, Stanford, California
| | | | - Julia Reid
- Myriad Genetics Inc., Salt Lake City, Utah
| | - Bryan Hennessy
- University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Gordon B Mills
- University of Texas MD Anderson Cancer Center, Houston, Texas
| | | | - Zoltan Szallasi
- Denmark Technical University, Lyngby, Denmark. Children's Hospital Boston, Boston, Massachusetts. Harvard Medical School, Boston, Massachusetts
| | - William T Barry
- Harvard Medical School, Boston, Massachusetts. Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Eric P Winer
- Harvard Medical School, Boston, Massachusetts. Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Nadine M Tung
- Harvard Medical School, Boston, Massachusetts. Beth Israel Deaconess Medical Center, Boston, Massachusetts
| | - Steven J Isakoff
- Harvard Medical School, Boston, Massachusetts. Massachusetts General Hospital, Boston, Massachusetts
| | - Paula D Ryan
- Massachusetts General Hospital, Boston, Massachusetts
| | | | | | | | | | - Chris Neff
- Myriad Genetics Inc., Salt Lake City, Utah
| | | | | | | | | | - Judy E Garber
- Harvard Medical School, Boston, Massachusetts. Dana-Farber Cancer Institute, Boston, Massachusetts
| | - James M Ford
- Stanford University School of Medicine, Stanford, California
| | - Daniel P Silver
- Harvard Medical School, Boston, Massachusetts. Dana-Farber Cancer Institute, Boston, Massachusetts.
| | - Andrea L Richardson
- Harvard Medical School, Boston, Massachusetts. Dana-Farber Cancer Institute, Boston, Massachusetts. Brigham and Women's Hospital, Boston, Massachusetts
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78
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CHK2-BRCA1 tumor-suppressor axis restrains oncogenic Aurora-A kinase to ensure proper mitotic microtubule assembly. Proc Natl Acad Sci U S A 2016; 113:1817-22. [PMID: 26831064 DOI: 10.1073/pnas.1525129113] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
BRCA1 (breast cancer type 1 susceptibility protein) is a multifunctional tumor suppressor involved in DNA damage response, DNA repair, chromatin regulation, and mitotic chromosome segregation. Although the nuclear functions of BRCA1 have been investigated in detail, its role during mitosis is little understood. It is clear, however, that loss of BRCA1 in human cancer cells leads to chromosomal instability (CIN), which is defined as a perpetual gain or loss of whole chromosomes during mitosis. Moreover, our recent work has revealed that the mitotic function of BRCA1 depends on its phosphorylation by the tumor-suppressor kinase Chk2 (checkpoint kinase 2) and that this regulation is required to ensure normal microtubule plus end assembly rates within mitotic spindles. Intriguingly, loss of the positive regulation of BRCA1 leads to increased oncogenic Aurora-A activity, which acts as a mediator for abnormal mitotic microtubule assembly resulting in chromosome missegregation and CIN. However, how the CHK2-BRCA1 tumor suppressor axis restrains oncogenic Aurora-A during mitosis to ensure karyotype stability remained an open question. Here we uncover a dual molecular mechanism by which the CHK2-BRCA1 axis restrains oncogenic Aurora-A activity during mitosis and identify BRCA1 itself as a target for Aurora-A relevant for CIN. In fact, Chk2-mediated phosphorylation of BRCA1 is required to recruit the PP6C-SAPS3 phosphatase, which acts as a T-loop phosphatase inhibiting Aurora-A bound to BRCA1. Consequently, loss of CHK2 or PP6C-SAPS3 promotes Aurora-A activity associated with BRCA1 in mitosis. Aurora-A, in turn, then phosphorylates BRCA1 itself, thereby inhibiting the mitotic function of BRCA1 and promoting mitotic microtubule assembly, chromosome missegregation, and CIN.
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79
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ER functions of oncogenes and tumor suppressors: Modulators of intracellular Ca(2+) signaling. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:1364-78. [PMID: 26772784 DOI: 10.1016/j.bbamcr.2016.01.002] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 01/04/2016] [Accepted: 01/05/2016] [Indexed: 12/20/2022]
Abstract
Intracellular Ca(2+) signals that arise from the endoplasmic reticulum (ER), the major intracellular Ca(2+)-storage organelle, impact several mitochondrial functions and dictate cell survival and cell death processes. Furthermore, alterations in Ca(2+) signaling in cancer cells promote survival and establish a high tolerance towards cell stress and damage, so that the on-going oncogenic stress does not result in the activation of cell death. Over the last years, the mechanisms underlying these oncogenic alterations in Ca(2+) signaling have started to emerge. An important aspect of this is the identification of several major oncogenes, including Bcl-2, Bcl-XL, Mcl-1, PKB/Akt, and Ras, and tumor suppressors, such as p53, PTEN, PML, BRCA1, and Beclin 1, as direct and critical regulators of Ca(2+)-transport systems located at the ER membranes, including IP3 receptors and SERCA Ca(2+) pumps. In this way, these proteins execute part of their function by controlling the ER-mitochondrial Ca(2+) fluxes, favoring either survival (oncogenes) or cell death (tumor suppressors). Oncogenic mutations, gene deletions or amplifications alter the expression and/or function of these proteins, thereby changing the delicate balance between oncogenes and tumor suppressors, impacting oncogenesis and favoring malignant cell function and behavior. In this review, we provided an integrated overview of the impact of the major oncogenes and tumor suppressors, often altered in cancer cells, on Ca(2+) signaling from the ER Ca(2+) stores. This article is part of a Special Issue entitled: Calcium and Cell Fate. Guest Editors: Jacques Haiech, Claus Heizmann, Joachim Krebs, Thierry Capiod and Olivier Mignen.
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80
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The putative oncogene CEP72 inhibits the mitotic function of BRCA1 and induces chromosomal instability. Oncogene 2015; 35:2398-406. [PMID: 26300001 DOI: 10.1038/onc.2015.290] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 06/15/2015] [Accepted: 07/06/2015] [Indexed: 01/21/2023]
Abstract
BRCA1 is a tumor-suppressor gene associated with, but not restricted to, breast and ovarian cancer and implicated in various biological functions. During mitosis, BRCA1 and its positive regulator Chk2 are localized at centrosomes and are required for the regulation of microtubule plus end assembly, thereby ensuring faithful mitosis and numerical chromosome stability. However, the function of BRCA1 during mitosis has not been defined mechanistically. To gain insights into the mitotic role of BRCA1 in regulating microtubule assembly, we systematically identified proteins interacting with BRCA1 during mitosis and found the centrosomal protein Cep72 as a novel BRCA1-interacting protein. CEP72 is frequently upregulated in colorectal cancer tissues and overexpression of CEP72 mirrors the consequences of BRCA1 loss during mitosis. In detail, the overexpression of CEP72 causes an increase in microtubule plus end assembly, abnormal mitotic spindle formation and the induction of chromosomal instability. Moreover, we show that high levels of Cep72 counteract Chk2 as a positive regulator of BRCA1 to ensure proper mitotic microtubule assembly. Thus, CEP72 represents a putative oncogene in colorectal cancer that might negatively regulate the mitotic function of BRCA1 to ensure chromosomal stability.
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81
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Liu Y, Hilakivi-Clarke L, Zhang Y, Wang X, Pan YX, Xuan J, Fleck SC, Doerge DR, Helferich WG. Isoflavones in soy flour diet have different effects on whole-genome expression patterns than purified isoflavone mix in human MCF-7 breast tumors in ovariectomized athymic nude mice. Mol Nutr Food Res 2015; 59:1419-30. [PMID: 25820259 PMCID: PMC5763549 DOI: 10.1002/mnfr.201500028] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 03/04/2015] [Accepted: 04/07/2015] [Indexed: 12/31/2022]
Abstract
SCOPE Soy flour diet (MS) prevented isoflavones from stimulating MCF-7 tumor growth in athymic nude mice, indicating that other bioactive compounds in soy can negate the estrogenic properties of isoflavones. The underlying signal transduction pathways to explain the protective effects of soy flour consumption were studied here. METHODS AND RESULTS Ovariectomized athymic nude mice inoculated with MCF-7 human breast cancer cells were fed either Soy flour diet (MS) or purified isoflavone mix diet (MI), both with equivalent amounts of genistein. Positive controls received estradiol pellets and negative controls received sham pellets. GeneChip Human Genome U133 Plus 2.0 Array platform was used to evaluate gene expressions, and results were analyzed using bioinformatics approaches. Tumors in MS-fed mice exhibited higher expression of tumor growth suppressing genes ATP2A3 and BLNK and lower expression of oncogene MYC. Tumors in MI-fed mice expressed a higher level of oncogene MYB and a lower level of MHC-I and MHC-II, allowing tumor cells to escape immunosurveillance. MS-induced gene expression alterations were predictive of prolonged survival among estrogen-receptor-positive breast cancer patients, whilst MI-induced gene changes were predictive of shortened survival. CONCLUSION Our findings suggest that dietary soy flour affects gene expression differently than purified isoflavones, which may explain why soy foods prevent isoflavones-induced stimulation of MCF-7 tumor growth in athymic nude mice.
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Affiliation(s)
- Yunxian Liu
- Department of Food Science and Human Nutrition, University of Illinois, Urbana-Champaign, IL 61801, USA
| | - Leena Hilakivi-Clarke
- Department of Oncology, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Yukun Zhang
- Department of Food Science and Human Nutrition, University of Illinois, Urbana-Champaign, IL 61801, USA
| | - Xiao Wang
- Bradley Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Arlington, VA 22203, USA
| | - Yuan-xiang Pan
- Department of Food Science and Human Nutrition, University of Illinois, Urbana-Champaign, IL 61801, USA
| | - Jianhua Xuan
- Bradley Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Arlington, VA 22203, USA
| | - Stefanie C. Fleck
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA
| | - Daniel R. Doerge
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA
| | - William G. Helferich
- Department of Food Science and Human Nutrition, University of Illinois, Urbana-Champaign, IL 61801, USA
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The expression of tumour suppressors and proto-oncogenes in tissues susceptible to their hereditary cancers. Br J Cancer 2015; 113:345-53. [PMID: 26079304 PMCID: PMC4506389 DOI: 10.1038/bjc.2015.205] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Revised: 03/05/2014] [Accepted: 05/15/2015] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Studies of familial cancers have found that only a small subset of tissues are affected by inherited mutations in a given tumour suppressor gene (TSG) or proto-oncogene (POG), even though the mutation is present in all tissues. Previous tests have shown that tissue specificity is not due to the presence vs absence of gene expression, as TSGs and POGs are expressed in nearly every type of normal human tissue. Using published microarray expression data we tested the related hypothesis that tissue-specific expression of a TSG or POG is highest in tissue where it is of oncogenic importance. METHODS We tested this hypothesis by examining whether individual TSGs and POGs had higher expression in the normal (noncancerous) tissues where they are implicated in familial cancers relative to those tissues where they are not. We examined data for 15 TSGs and 8 POGs implicated in familial cancer across 12 human tissue types. RESULTS We found a significant difference between expression levels in susceptible vs nonsusceptible tissues. It was found that 9 (60%, P<0.001) of the TSGs and 5 (63%, P<0.001) of the POGs had their highest expression level in the tissue type susceptible to their oncogenic effect. CONCLUSIONS This highly significant association supports the hypothesis that mutation of a specific TSG or POG is likely to be most oncogenic in the tissue where the gene has its highest level of expression. This suggests that high expression in normal tissues is a potential marker for linking cancer-related genes with their susceptible tissues.
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Hatchi E, Skourti-Stathaki K, Ventz S, Pinello L, Yen A, Kamieniarz-Gdula K, Dimitrov S, Pathania S, McKinney KM, Eaton ML, Kellis M, Hill SJ, Parmigiani G, Proudfoot NJ, Livingston DM. BRCA1 recruitment to transcriptional pause sites is required for R-loop-driven DNA damage repair. Mol Cell 2015; 57:636-647. [PMID: 25699710 PMCID: PMC4351672 DOI: 10.1016/j.molcel.2015.01.011] [Citation(s) in RCA: 311] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 11/21/2014] [Accepted: 01/05/2015] [Indexed: 11/07/2022]
Abstract
The mechanisms contributing to transcription-associated genomic instability are both complex and incompletely understood. Although R-loops are normal transcriptional intermediates, they are also associated with genomic instability. Here, we show that BRCA1 is recruited to R-loops that form normally over a subset of transcription termination regions. There it mediates the recruitment of a specific, physiological binding partner, senataxin (SETX). Disruption of this complex led to R-loop-driven DNA damage at those loci as reflected by adjacent γ-H2AX accumulation and ssDNA breaks within the untranscribed strand of relevant R-loop structures. Genome-wide analysis revealed widespread BRCA1 binding enrichment at R-loop-rich termination regions (TRs) of actively transcribed genes. Strikingly, within some of these genes in BRCA1 null breast tumors, there are specific insertion/deletion mutations located close to R-loop-mediated BRCA1 binding sites within TRs. Thus, BRCA1/SETX complexes support a DNA repair mechanism that addresses R-loop-based DNA damage at transcriptional pause sites. Endogenous BRCA1 and senataxin (SETX) interact in a BRCA1-driven process BRCA1/SETX complexes are recruited to R-loop-associated termination regions (TRs) BRCA1/SETX complexes suppress transcriptional DNA damage arising at nearby R-loops BRCA1 breast cancers reveal indel mutations near BRCA1 TR binding regions
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Affiliation(s)
- Elodie Hatchi
- Department of Genetics, Harvard Medical School, Boston, MA 02215, USA; Department of Cancer Biology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215, USA.
| | | | - Steffen Ventz
- Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215, USA; Department of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA
| | - Luca Pinello
- Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215, USA; Department of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA
| | - Angela Yen
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Computer Science and Artificial Intelligence Laboratory (CSAIL), MIT, Cambridge, MA 02139, USA
| | | | - Stoil Dimitrov
- Department of Genetics, Harvard Medical School, Boston, MA 02215, USA; Department of Cancer Biology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215, USA
| | - Shailja Pathania
- Department of Genetics, Harvard Medical School, Boston, MA 02215, USA; Department of Cancer Biology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215, USA
| | - Kristine M McKinney
- Department of Genetics, Harvard Medical School, Boston, MA 02215, USA; Department of Cancer Biology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215, USA
| | - Matthew L Eaton
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Computer Science and Artificial Intelligence Laboratory (CSAIL), MIT, Cambridge, MA 02139, USA
| | - Manolis Kellis
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Computer Science and Artificial Intelligence Laboratory (CSAIL), MIT, Cambridge, MA 02139, USA
| | - Sarah J Hill
- Department of Genetics, Harvard Medical School, Boston, MA 02215, USA; Department of Cancer Biology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215, USA
| | - Giovanni Parmigiani
- Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215, USA; Department of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA
| | | | - David M Livingston
- Department of Genetics, Harvard Medical School, Boston, MA 02215, USA; Department of Cancer Biology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215, USA.
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84
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Pettapiece-Phillips R, Narod SA, Kotsopoulos J. The role of body size and physical activity on the risk of breast cancer in BRCA mutation carriers. Cancer Causes Control 2015; 26:333-44. [PMID: 25579073 DOI: 10.1007/s10552-014-0521-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 12/23/2014] [Indexed: 01/18/2023]
Abstract
Women who inherit a BRCA mutation face a high lifetime risk of developing breast cancer. Given the high penetrance of these mutations, prevention is of extreme importance. Here, we review the literature regarding the role of body size and of physical activity in the context of BRCA-associated breast cancer. There is some evidence to support a protective role of a healthy body size and of regular physical activity among mutation carriers, particularly during adolescence or early adulthood. Factors which increase the physiologic expression of the normal copy of the BRCA1 or BRCA2 gene and thereby normalize protein levels, contribute to stem cell homeostasis, and/or affect hormone levels, might mitigate the effects of an inherited BRCA mutation. Preliminary evidence from one in vivo study and from one epidemiologic report suggests that an increase in BRCA1 mRNA expression occurs with increasing levels of physical activity. The prospect of changing lifestyle for the purpose of preventing breast cancer in high-risk women, complemented by mechanistic evidence, warrants evaluation in large-scale prospective studies.
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Affiliation(s)
- Rachael Pettapiece-Phillips
- Women's College Research Institute, Women's College Hospital, 790 Bay Street, 7th Floor, Toronto, ON, M5G 1N8, Canada
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85
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Albarakati N, Abdel-Fatah TMA, Doherty R, Russell R, Agarwal D, Moseley P, Perry C, Arora A, Alsubhi N, Seedhouse C, Rakha EA, Green A, Ball G, Chan S, Caldas C, Ellis IO, Madhusudan S. Targeting BRCA1-BER deficient breast cancer by ATM or DNA-PKcs blockade either alone or in combination with cisplatin for personalized therapy. Mol Oncol 2015; 9:204-17. [PMID: 25205036 PMCID: PMC5528668 DOI: 10.1016/j.molonc.2014.08.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 07/23/2014] [Accepted: 08/11/2014] [Indexed: 11/17/2022] Open
Abstract
BRCA1, a key factor in homologous recombination (HR) repair may also regulate base excision repair (BER). Targeting BRCA1-BER deficient cells by blockade of ATM and DNA-PKcs could be a promising strategy in breast cancer. We investigated BRCA1, XRCC1 and pol β protein expression in two cohorts (n = 1602 sporadic and n = 50 germ-line BRCA1 mutated) and mRNA expression in two cohorts (n = 1952 and n = 249). Artificial neural network analysis for BRCA1-DNA repair interacting genes was conducted in 249 tumours. Pre-clinically, BRCA1 proficient and deficient cells were DNA repair expression profiled and evaluated for synthetic lethality using ATM and DNA-PKcs inhibitors either alone or in combination with cisplatin. In human tumours, BRCA1 negativity was strongly associated with low XRCC1, and low pol β at mRNA and protein levels (p < 0.0001). In patients with BRCA1 negative tumours, low XRCC1 or low pol β expression was significantly associated with poor survival in univariate and multivariate analysis compared to high XRCC1 or high pol β expressing BRCA1 negative tumours (ps < 0.05). Pre-clinically, BRCA1 negative cancer cells exhibit low mRNA and low protein expression of XRCC1 and pol β. BRCA1-BER deficient cells were sensitive to ATM and DNA-PKcs inhibitor treatment either alone or in combination with cisplatin and synthetic lethality was evidenced by DNA double strand breaks accumulation, cell cycle arrest and apoptosis. We conclude that XRCC1 and pol β expression status in BRCA1 negative tumours may have prognostic significance. BRCA1-BER deficient cells could be targeted by ATM or DNA-PKcs inhibitors for personalized therapy.
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Affiliation(s)
- Nada Albarakati
- Academic Unit of Oncology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham NG51PB, UK
| | | | - Rachel Doherty
- Academic Unit of Oncology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham NG51PB, UK
| | - Roslin Russell
- Cancer Research UK, Cambridge Research Institute, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Devika Agarwal
- School of Science and Technology, Nottingham Trent University, Clifton Campus, Nottingham NG11 8NS, UK
| | - Paul Moseley
- Department of Oncology, Nottingham University Hospitals, Nottingham NG51PB, UK
| | - Christina Perry
- Academic Unit of Oncology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham NG51PB, UK
| | - Arvind Arora
- Academic Unit of Oncology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham NG51PB, UK
| | - Nouf Alsubhi
- Academic Unit of Oncology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham NG51PB, UK
| | - Claire Seedhouse
- Academic Haematology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham NG51PB, UK
| | - Emad A Rakha
- Department of Pathology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham NG51PB, UK
| | - Andrew Green
- Department of Pathology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham NG51PB, UK
| | - Graham Ball
- School of Science and Technology, Nottingham Trent University, Clifton Campus, Nottingham NG11 8NS, UK
| | - Stephen Chan
- Department of Oncology, Nottingham University Hospitals, Nottingham NG51PB, UK
| | - Carlos Caldas
- Cancer Research UK, Cambridge Research Institute, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Ian O Ellis
- Department of Pathology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham NG51PB, UK
| | - Srinivasan Madhusudan
- Academic Unit of Oncology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham University Hospitals, Nottingham NG51PB, UK; Department of Oncology, Nottingham University Hospitals, Nottingham NG51PB, UK.
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86
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Gupta R, Liu AY, Glazer PM, Wajapeyee N. LKB1 preserves genome integrity by stimulating BRCA1 expression. Nucleic Acids Res 2014; 43:259-71. [PMID: 25488815 PMCID: PMC4288185 DOI: 10.1093/nar/gku1294] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Serine/threonine kinase 11 (STK11, also known as LKB1) functions as a tumor suppressor in many human cancers. However, paradoxically loss of LKB1 in mouse embryonic fibroblast results in resistance to oncogene-induced transformation. Therefore, it is unclear why loss of LKB1 leads to increased predisposition to develop a wide variety of cancers. Here, we show that LKB1 protects cells from genotoxic stress. Cells lacking LKB1 display increased sensitivity to irradiation, accumulates more DNA double-strand breaks, display defective homology-directed DNA repair (HDR) and exhibit increased mutation rate, compared with that of LKB1-expressing cells. Conversely, the ectopic expression of LKB1 in cells lacking LKB1 protects them against genotoxic stress-induced DNA damage and prevents the accumulation of mutations. We find that LKB1 post-transcriptionally stimulates HDR gene BRCA1 expression by inhibiting the cytoplasmic localization of the RNA-binding protein, HU antigen R, in an AMP kinase-dependent manner and stabilizes BRCA1 mRNA. Cells lacking BRCA1 similar to the cell lacking LKB1 display increased genomic instability and ectopic expression of BRCA1 rescues LKB1 loss-induced sensitivity to genotoxic stress. Collectively, our results demonstrate that LKB1 is a crucial regulator of genome integrity and reveal a novel mechanism for LKB1-mediated tumor suppression with direct therapeutic implications for cancer prevention.
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Affiliation(s)
- Romi Gupta
- Department of Pathology, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Alex Y Liu
- Department of Pathology, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Peter M Glazer
- Department of Therapeutic Radiology and Genetics, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Narendra Wajapeyee
- Department of Pathology, Yale University School of Medicine, New Haven, CT 06510, USA
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87
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Kumaraswamy E, Wendt KL, Augustine LA, Stecklein SR, Sibala EC, Li D, Gunewardena S, Jensen RA. BRCA1 regulation of epidermal growth factor receptor (EGFR) expression in human breast cancer cells involves microRNA-146a and is critical for its tumor suppressor function. Oncogene 2014; 34:4333-46. [PMID: 25417703 DOI: 10.1038/onc.2014.363] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Revised: 09/03/2014] [Accepted: 09/05/2014] [Indexed: 01/27/2023]
Abstract
Breast cancer 1 (BRCA1)-associated breast cancers are mostly basal-like high-grade ductal carcinomas that frequently overexpress epidermal growth factor receptor (EGFR). Aberrant EGFR expression is correlated with disease progression, resistance to radiation and chemotherapy, and poor clinical prognosis. Although BRCA1 is involved in multiple cellular processes, its functional role in EGFR regulation remains enigmatic. Here, we report a previously unrecognized posttranscriptional mechanism by which BRCA1 regulates EGFR expression through the induction of miR-146a. We demonstrate that EGFR expression correlates negatively with BRCA1, whereas miR-146a levels increase with BRCA1. We show that BRCA1 binds to MIR146A promoter and activates transcription, which in turn attenuates EGFR expression. Knockdown of miR-146a in BRCA1-overexpressing cells negated this effect and suppressed its ability to inhibit proliferation and transformation. In archived triple-negative breast cancer samples, we show a strong positive correlation between BRCA1 and miR-146a expression. We also show that low expression of miR-146a strongly predicts positive lymph node status and is associated with distinctively poor overall survival of patients. Together, these observations provide an insight into a novel BRCA1miR-146aEGFR paradigm by which BRCA1 carries out an aspect of tumor suppressor function that is potentially amenable to therapeutic intervention.
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Affiliation(s)
- E Kumaraswamy
- 1] Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS, USA [2] The University of Kansas Cancer Center, Kansas City, KS, USA
| | - K L Wendt
- The University of Kansas Cancer Center, Kansas City, KS, USA
| | - L A Augustine
- The University of Kansas Cancer Center, Kansas City, KS, USA
| | - S R Stecklein
- Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS, USA
| | - E C Sibala
- The University of Kansas Cancer Center, Kansas City, KS, USA
| | - D Li
- The University of Kansas Cancer Center, Kansas City, KS, USA
| | - S Gunewardena
- 1] Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA [2] Department of Biostatistics, University of Kansas Medical Center, Kansas City, KS, USA
| | - R A Jensen
- 1] Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS, USA [2] The University of Kansas Cancer Center, Kansas City, KS, USA [3] Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS, USA [4] Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS, USA [5] Department of Molecular Biosciences, University of Kansas, Lawrence, KS, USA
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88
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Pathania S, Bade S, Le Guillou M, Burke K, Reed R, Bowman-Colin C, Su Y, Ting DT, Polyak K, Richardson AL, Feunteun J, Garber JE, Livingston DM. BRCA1 haploinsufficiency for replication stress suppression in primary cells. Nat Commun 2014; 5:5496. [PMID: 25400221 PMCID: PMC4243249 DOI: 10.1038/ncomms6496] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 10/07/2014] [Indexed: 12/14/2022] Open
Abstract
BRCA1—a breast and ovarian cancer suppressor gene—promotes genome integrity. To study the functionality of BRCA1 in the heterozygous state, we established a collection of primary human BRCA1+/+ and BRCA1mut/+ mammary epithelial cells and fibroblasts. Here we report that all BRCA1mut/+ cells exhibited multiple normal BRCA1 functions, including the support of homologous recombination- type double-strand break repair (HR-DSBR), checkpoint functions, centrosome number control, spindle pole formation, Slug expression and satellite RNA suppression. In contrast, the same cells were defective in stalled replication fork repair and/or suppression of fork collapse, that is, replication stress. These defects were rescued by reconstituting BRCA1mut/+ cells with wt BRCA1. In addition, we observed ‘conditional’ haploinsufficiency for HR-DSBR in BRCA1mut/+ cells in the face of replication stress. Given the importance of replication stress in epithelial cancer development and of an HR defect in breast cancer pathogenesis, both defects are candidate contributors to tumorigenesis in BRCA1-deficient mammary tissue. BRCA1 is a key breast and ovarian cancer suppressor involved in DSB repair. Here, the authors show that cells heterozygous for several BRCA1 mutations are universally defective in the response to replication stress, which could contribute to the BRCA1 breast cancer development pathway.
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Affiliation(s)
- Shailja Pathania
- 1] Harvard Medical School, Boston, Massachusetts 02115, USA [2] Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
| | - Sangeeta Bade
- Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
| | - Morwenna Le Guillou
- Stabilité Génétique et Oncogenèse, Université Paris-Sud, CNRS-UMR8200, Gustave-Roussy, Villejuif 94805, France
| | - Karly Burke
- Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Rachel Reed
- Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
| | - Christian Bowman-Colin
- 1] Harvard Medical School, Boston, Massachusetts 02115, USA [2] Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
| | - Ying Su
- Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
| | - David T Ting
- 1] Harvard Medical School, Boston, Massachusetts 02115, USA [2] Department of Hematology/Oncology, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA
| | - Kornelia Polyak
- 1] Harvard Medical School, Boston, Massachusetts 02115, USA [2] Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
| | - Andrea L Richardson
- 1] Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA [2] Brigham and Women's Hospital, Harvard Medical School, 75 Francis St, Boston, Massachusetts 02115, USA
| | - Jean Feunteun
- Stabilité Génétique et Oncogenèse, Université Paris-Sud, CNRS-UMR8200, Gustave-Roussy, Villejuif 94805, France
| | - Judy E Garber
- 1] Harvard Medical School, Boston, Massachusetts 02115, USA [2] Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
| | - David M Livingston
- 1] Harvard Medical School, Boston, Massachusetts 02115, USA [2] Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
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89
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Hill SJ, Clark AP, Silver DP, Livingston DM. BRCA1 pathway function in basal-like breast cancer cells. Mol Cell Biol 2014; 34:3828-42. [PMID: 25092866 PMCID: PMC4187718 DOI: 10.1128/mcb.01646-13] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 02/20/2014] [Accepted: 07/21/2014] [Indexed: 01/10/2023] Open
Abstract
Sporadic basal-like cancers (BLCs) are a common subtype of breast cancer that share multiple biological properties with BRCA1-mutated breast tumors. Despite being BRCA1(+/+), sporadic BLCs are widely viewed as phenocopies of BRCA1-mutated breast cancers, because they are hypothesized to manifest a BRCA1 functional defect or breakdown of a pathway(s) in which BRCA1 plays a major role. The role of BRCA1 in the repair of double-strand DNA breaks by homologous recombination (HR) is its best understood function and the function most often implicated in BRCA1 breast cancer suppression. Therefore, it is suspected that sporadic BLCs exhibit a defect in HR. To test this hypothesis, multiple DNA damage repair assays focused on several types of repair were performed on a group of cell lines classified as sporadic BLCs and on controls. The sporadic BLC cell lines failed to exhibit an overt HR defect. Rather, they exhibited defects in the repair of stalled replication forks, another BRCA1 function. These results provide insight into why clinical trials of poly(ADP-ribose) polymerase (PARP) inhibitors, which require an HR defect for efficacy, have been unsuccessful in sporadic BLCs, unlike cisplatin, which elicits DNA damage that requires stalled fork repair and has shown efficacy in sporadic BLCs.
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Affiliation(s)
- Sarah J Hill
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, USA Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Allison P Clark
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Daniel P Silver
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - David M Livingston
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, USA Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
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90
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Long DT, Joukov V, Budzowska M, Walter JC. BRCA1 promotes unloading of the CMG helicase from a stalled DNA replication fork. Mol Cell 2014; 56:174-85. [PMID: 25219499 DOI: 10.1016/j.molcel.2014.08.012] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 06/30/2014] [Accepted: 08/07/2014] [Indexed: 11/19/2022]
Abstract
The tumor suppressor protein BRCA1 promotes homologous recombination (HR), a high-fidelity mechanism to repair DNA double-strand breaks (DSBs) that arise during normal replication and in response to DNA-damaging agents. Recent genetic experiments indicate that BRCA1 also performs an HR-independent function during the repair of DNA interstrand crosslinks (ICLs). Here we show that BRCA1 is required to unload the CMG helicase complex from chromatin after replication forks collide with an ICL. Eviction of the stalled helicase allows leading strands to be extended toward the ICL, followed by endonucleolytic processing of the crosslink, lesion bypass, and DSB repair. Our results identify BRCA1-dependent helicase unloading as a critical, early event in ICL repair.
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Affiliation(s)
- David T Long
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Vladimir Joukov
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Magda Budzowska
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Johannes C Walter
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA.
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91
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Gierach GL, Li H, Loud JT, Greene MH, Chow CK, Lan L, Prindiville SA, Eng-Wong J, Soballe PW, Giambartolomei C, Mai PL, Galbo CE, Nichols K, Calzone KA, Olopade OI, Gail MH, Giger ML. Relationships between computer-extracted mammographic texture pattern features and BRCA1/2 mutation status: a cross-sectional study. Breast Cancer Res 2014. [PMID: 25159706 DOI: 10.1186/preaccept-1744229618121391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
INTRODUCTION Mammographic density is similar among women at risk of either sporadic or BRCA1/2-related breast cancer. It has been suggested that digitized mammographic images contain computer-extractable information within the parenchymal pattern, which may contribute to distinguishing between BRCA1/2 mutation carriers and non-carriers. METHODS We compared mammographic texture pattern features in digitized mammograms from women with deleterious BRCA1/2 mutations (n = 137) versus non-carriers (n = 100). Subjects were stratified into training (107 carriers, 70 non-carriers) and testing (30 carriers, 30 non-carriers) datasets. Masked to mutation status, texture features were extracted from a retro-areolar region-of-interest in each subject's digitized mammogram. Stepwise linear regression analysis of the training dataset identified variables to be included in a radiographic texture analysis (RTA) classifier model aimed at distinguishing BRCA1/2 carriers from non-carriers. The selected features were combined using a Bayesian Artificial Neural Network (BANN) algorithm, which produced a probability score rating the likelihood of each subject's belonging to the mutation-positive group. These probability scores were evaluated in the independent testing dataset to determine whether their distribution differed between BRCA1/2 mutation carriers and non-carriers. A receiver operating characteristic analysis was performed to estimate the model's discriminatory capacity. RESULTS In the testing dataset, a one standard deviation (SD) increase in the probability score from the BANN-trained classifier was associated with a two-fold increase in the odds of predicting BRCA1/2 mutation status: unadjusted odds ratio (OR) = 2.00, 95% confidence interval (CI): 1.59, 2.51, P = 0.02; age-adjusted OR = 1.93, 95% CI: 1.53, 2.42, P = 0.03. Additional adjustment for percent mammographic density did little to change the OR. The area under the curve for the BANN-trained classifier to distinguish between BRCA1/2 mutation carriers and non-carriers was 0.68 for features alone and 0.72 for the features plus percent mammographic density. CONCLUSIONS Our findings suggest that, unlike percent mammographic density, computer-extracted mammographic texture pattern features are associated with carrying BRCA1/2 mutations. Although still at an early stage, our novel RTA classifier has potential for improving mammographic image interpretation by permitting real-time risk stratification among women undergoing screening mammography.
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Affiliation(s)
- Gretchen L Gierach
- Hormonal and Reproductive Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, 9609 Medical Center Drive, Rm, 7-E108, Bethesda 20892-9774, MD, USA.
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92
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Gierach GL, Li H, Loud JT, Greene MH, Chow CK, Lan L, Prindiville SA, Eng-Wong J, Soballe PW, Giambartolomei C, Mai PL, Galbo CE, Nichols K, Calzone KA, Olopade OI, Gail MH, Giger ML. Relationships between computer-extracted mammographic texture pattern features and BRCA1/2 mutation status: a cross-sectional study. Breast Cancer Res 2014; 16:424. [PMID: 25159706 PMCID: PMC4268674 DOI: 10.1186/s13058-014-0424-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 07/31/2014] [Indexed: 12/24/2022] Open
Abstract
Introduction Mammographic density is similar among women at risk of either sporadic or BRCA1/2-related breast cancer. It has been suggested that digitized mammographic images contain computer-extractable information within the parenchymal pattern, which may contribute to distinguishing between BRCA1/2 mutation carriers and non-carriers. Methods We compared mammographic texture pattern features in digitized mammograms from women with deleterious BRCA1/2 mutations (n = 137) versus non-carriers (n = 100). Subjects were stratified into training (107 carriers, 70 non-carriers) and testing (30 carriers, 30 non-carriers) datasets. Masked to mutation status, texture features were extracted from a retro-areolar region-of-interest in each subject’s digitized mammogram. Stepwise linear regression analysis of the training dataset identified variables to be included in a radiographic texture analysis (RTA) classifier model aimed at distinguishing BRCA1/2 carriers from non-carriers. The selected features were combined using a Bayesian Artificial Neural Network (BANN) algorithm, which produced a probability score rating the likelihood of each subject’s belonging to the mutation-positive group. These probability scores were evaluated in the independent testing dataset to determine whether their distribution differed between BRCA1/2 mutation carriers and non-carriers. A receiver operating characteristic analysis was performed to estimate the model’s discriminatory capacity. Results In the testing dataset, a one standard deviation (SD) increase in the probability score from the BANN-trained classifier was associated with a two-fold increase in the odds of predicting BRCA1/2 mutation status: unadjusted odds ratio (OR) = 2.00, 95% confidence interval (CI): 1.59, 2.51, P = 0.02; age-adjusted OR = 1.93, 95% CI: 1.53, 2.42, P = 0.03. Additional adjustment for percent mammographic density did little to change the OR. The area under the curve for the BANN-trained classifier to distinguish between BRCA1/2 mutation carriers and non-carriers was 0.68 for features alone and 0.72 for the features plus percent mammographic density. Conclusions Our findings suggest that, unlike percent mammographic density, computer-extracted mammographic texture pattern features are associated with carrying BRCA1/2 mutations. Although still at an early stage, our novel RTA classifier has potential for improving mammographic image interpretation by permitting real-time risk stratification among women undergoing screening mammography. Electronic supplementary material The online version of this article (doi:10.1186/s13058-014-0424-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Gretchen L Gierach
- Hormonal and Reproductive Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, 9609 Medical Center Drive, Rm, 7-E108, Bethesda 20892-9774, MD, USA.
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93
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Khurana S, Kruhlak MJ, Kim J, Tran AD, Liu J, Nyswaner K, Shi L, Jailwala P, Sung MH, Hakim O, Oberdoerffer P. A macrohistone variant links dynamic chromatin compaction to BRCA1-dependent genome maintenance. Cell Rep 2014; 8:1049-62. [PMID: 25131201 PMCID: PMC4154351 DOI: 10.1016/j.celrep.2014.07.024] [Citation(s) in RCA: 157] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 04/28/2014] [Accepted: 07/16/2014] [Indexed: 02/07/2023] Open
Abstract
Appropriate DNA double-strand break (DSB) repair factor choice is essential for ensuring accurate repair outcome and genomic integrity. The factors that regulate this process remain poorly understood. Here, we identify two repressive chromatin components, the macrohistone variant macroH2A1 and the H3K9 methyltransferase and tumor suppressor PRDM2, which together direct the choice between the antagonistic DSB repair mediators BRCA1 and 53BP1. The macroH2A1/PRDM2 module mediates an unexpected shift from accessible to condensed chromatin that requires the ataxia telangiectasia mutated (ATM)-dependent accumulation of both proteins at DSBs in order to promote DSB-flanking H3K9 dimethylation. Remarkably, loss of macroH2A1 or PRDM2, as well as experimentally induced chromatin decondensation, impairs the retention of BRCA1, but not 53BP1, at DSBs. As a result, mac-roH2A1 and/or PRDM2 depletion causes epistatic defects in DSB end resection, homology-directed repair, and the resistance to poly(ADP-ribose) polymerase (PARP) inhibition—all hallmarks of BRCA1-deficient tumors. Together, these findings identify dynamic, DSB-associated chromatin reorganization as a critical modulator of BRCA1-dependent genome maintenance.
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Affiliation(s)
- Simran Khurana
- Laboratory of Receptor Biology and Gene Expression, NCI/NIH, Bethesda, MD 20892, USA
| | | | - Jeongkyu Kim
- Laboratory of Receptor Biology and Gene Expression, NCI/NIH, Bethesda, MD 20892, USA
| | - Andy D Tran
- Laboratory of Receptor Biology and Gene Expression, NCI/NIH, Bethesda, MD 20892, USA
| | - Jinping Liu
- Laboratory of Receptor Biology and Gene Expression, NCI/NIH, Bethesda, MD 20892, USA
| | | | - Lei Shi
- Department of Biochemistry and Molecular Biology, Tianjin Medical University, Tianjin 300070, China
| | - Parthav Jailwala
- Advanced Biomedical Computing Center, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc., Frederick, MD 21702, USA
| | - Myong-Hee Sung
- Laboratory of Receptor Biology and Gene Expression, NCI/NIH, Bethesda, MD 20892, USA
| | - Ofir Hakim
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Philipp Oberdoerffer
- Laboratory of Receptor Biology and Gene Expression, NCI/NIH, Bethesda, MD 20892, USA.
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94
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Polato F, Callen E, Wong N, Faryabi R, Bunting S, Chen HT, Kozak M, Kruhlak MJ, Reczek CR, Lee WH, Ludwig T, Baer R, Feigenbaum L, Jackson S, Nussenzweig A. CtIP-mediated resection is essential for viability and can operate independently of BRCA1. ACTA ACUST UNITED AC 2014; 211:1027-36. [PMID: 24842372 PMCID: PMC4042650 DOI: 10.1084/jem.20131939] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In contrast to BRCA1, CtIP has indispensable roles in promoting resection and embryonic development. Homologous recombination (HR) is initiated by DNA end resection, a process in which stretches of single-strand DNA (ssDNA) are generated and used for homology search. Factors implicated in resection include nucleases MRE11, EXO1, and DNA2, which process DNA ends into 3′ ssDNA overhangs; helicases such as BLM, which unwind DNA; and other proteins such as BRCA1 and CtIP whose functions remain unclear. CDK-mediated phosphorylation of CtIP on T847 is required to promote resection, whereas CDK-dependent phosphorylation of CtIP-S327 is required for interaction with BRCA1. Here, we provide evidence that CtIP functions independently of BRCA1 in promoting DSB end resection. First, using mouse models expressing S327A or T847A mutant CtIP as a sole species, and B cells deficient in CtIP, we show that loss of the CtIP-BRCA1 interaction does not detectably affect resection, maintenance of genomic stability or viability, whereas T847 is essential for these functions. Second, although loss of 53BP1 rescues the embryonic lethality and HR defects in BRCA1-deficient mice, it does not restore viability or genome integrity in CtIP−/− mice. Third, the increased resection afforded by loss of 53BP1 and the rescue of BRCA1-deficiency depend on CtIP but not EXO1. Finally, the sensitivity of BRCA1-deficient cells to poly ADP ribose polymerase (PARP) inhibition is partially rescued by the phospho-mimicking mutant CtIP (CtIP-T847E). Thus, in contrast to BRCA1, CtIP has indispensable roles in promoting resection and embryonic development.
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Affiliation(s)
- Federica Polato
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Elsa Callen
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Nancy Wong
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Robert Faryabi
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Samuel Bunting
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Hua-Tang Chen
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Marina Kozak
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Michael J Kruhlak
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Colleen R Reczek
- Institute for Cancer Genetics, Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032
| | - Wen-Hwa Lee
- Department of Biological Chemistry, School of Medicine, University of California, Irvine, CA 92697
| | - Thomas Ludwig
- Ohio State University Wexner Medical Center, Columbus, OH 43210
| | - Richard Baer
- Institute for Cancer Genetics, Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032
| | - Lionel Feigenbaum
- Science Applications International Corporation-Frederick National Cancer Institute-Frederick Cancer Research and Development Center, Frederick, MD 21704
| | - Stephen Jackson
- The Wellcome Trust and Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, England, UK The Wellcome Trust and Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, England, UK The Wellcome Trust Sanger Institute, Hinxton CB10 1SA, England, UK
| | - André Nussenzweig
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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95
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Yi YW, Kang HJ, Bae I. BRCA1 and Oxidative Stress. Cancers (Basel) 2014; 6:771-95. [PMID: 24704793 PMCID: PMC4074803 DOI: 10.3390/cancers6020771] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 03/20/2014] [Accepted: 03/24/2014] [Indexed: 01/07/2023] Open
Abstract
The breast cancer susceptibility gene 1 (BRCA1) has been well established as a tumor suppressor and functions primarily by maintaining genome integrity. Genome stability is compromised when cells are exposed to oxidative stress. Increasing evidence suggests that BRCA1 regulates oxidative stress and this may be another mechanism in preventing carcinogenesis in normal cells. Oxidative stress caused by reactive oxygen species (ROS) is implicated in carcinogenesis and is used strategically to treat human cancer. Thus, it is essential to understand the function of BRCA1 in oxidative stress regulation. In this review, we briefly summarize BRCA1's many binding partners and mechanisms, and discuss data supporting the function of BRCA1 in oxidative stress regulation. Finally, we consider its significance in prevention and/or treatment of BRCA1-related cancers.
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Affiliation(s)
- Yong Weon Yi
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA.
| | - Hyo Jin Kang
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA.
| | - Insoo Bae
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA.
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96
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Jackson KC, Gidlund EK, Norrbom J, Valencia AP, Thomson DM, Schuh RA, Neufer PD, Spangenburg EE. BRCA1 is a novel regulator of metabolic function in skeletal muscle. J Lipid Res 2014; 55:668-80. [PMID: 24565757 PMCID: PMC3966701 DOI: 10.1194/jlr.m043851] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2013] [Revised: 01/28/2014] [Indexed: 12/19/2022] Open
Abstract
Breast cancer type 1 (BRCA1) susceptibility protein is expressed across multiple tissues including skeletal muscle. The overall objective of this investigation was to define a functional role for BRCA1 in skeletal muscle using a translational approach. For the first time in both mice and humans, we identified the presence of multiple isoforms of BRCA1 in skeletal muscle. In response to an acute bout of exercise, we found increases in the interaction between the native forms of BRCA1 and the phosphorylated form of acetyl-CoA carboxylase. Decreasing BRCA1 content using a shRNA approach in cultured primary human myotubes resulted in decreased oxygen consumption by the mitochondria and increased reactive oxygen species production. The decreased BRCA1 content also resulted in increased storage of intracellular lipid and reduced insulin signaling. These results indicate that BRCA1 plays a critical role in the regulation of metabolic function in skeletal muscle. Collectively, these data reveal BRCA1 as a novel target to consider in our understanding of metabolic function and risk for development of metabolic-based diseases.
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Affiliation(s)
- Kathryn C. Jackson
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, MD
| | - Eva-Karin Gidlund
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Jessica Norrbom
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Ana P. Valencia
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, MD
| | - David M. Thomson
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT
| | - Rosemary A. Schuh
- Research Service, Maryland Veteran Affairs Health Care System, Baltimore, MD
- Department of Neurology, School of Medicine, University of Maryland, Baltimore, MD
| | - P. Darrell Neufer
- Departments of Physiology and Kinesiology, East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC
| | - Espen E. Spangenburg
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, MD
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97
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Abbas M, Shanmugam I, Bsaili M, Hromas R, Shaheen M. The role of the human psoralen 4 (hPso4) protein complex in replication stress and homologous recombination. J Biol Chem 2014; 289:14009-19. [PMID: 24675077 DOI: 10.1074/jbc.m113.520056] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Psoralen 4 (Pso4) is an evolutionarily conserved protein that has been implicated in a variety of cellular processes including RNA splicing and resistance to agents that cause DNA interstrand cross-links. Here we show that the hPso4 complex is required for timely progression through S phase and transition through the G2/M checkpoint, and it functions in the repair of DNA lesions that arise during replication. Notably, hPso4 depletion results in delayed resumption of DNA replication after hydroxyurea-induced stalling of replication forks, reduced repair of spontaneous and hydroxyurea-induced DNA double strand breaks (DSBs), and increased sensitivity to a poly(ADP-ribose) polymerase inhibitor. Furthermore, we show that hPso4 is involved in the repair of DSBs by homologous recombination, probably by regulating the BRCA1 protein levels and the generation of single strand DNA at DSBs. Together, our results demonstrate that hPso4 participates in cell proliferation and the maintenance of genome stability by regulating homologous recombination. The involvement of hPso4 in the recombinational repair of DSBs provides an explanation for the sensitivity of Pso4-deficient cells to DNA interstrand cross-links.
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Affiliation(s)
- Mohammad Abbas
- From the Division of Hematology-Oncology, Department of Internal Medicine, University of New Mexico, Albuquerque, New Mexico 87131 and
| | - Ilanchezhian Shanmugam
- From the Division of Hematology-Oncology, Department of Internal Medicine, University of New Mexico, Albuquerque, New Mexico 87131 and
| | - Manal Bsaili
- From the Division of Hematology-Oncology, Department of Internal Medicine, University of New Mexico, Albuquerque, New Mexico 87131 and
| | - Robert Hromas
- the Department of Medicine, University of Florida, Gainesville, Florida 32611
| | - Monte Shaheen
- From the Division of Hematology-Oncology, Department of Internal Medicine, University of New Mexico, Albuquerque, New Mexico 87131 and
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98
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Loss of Caenorhabditis elegans BRCA1 promotes genome stability during replication in smc-5 mutants. Genetics 2014; 196:985-99. [PMID: 24424777 PMCID: PMC3982690 DOI: 10.1534/genetics.113.158295] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
DNA damage by ultraviolet (UV) light poses a risk for mutagenesis and a potential hindrance for cell cycle progression. Cells cope with UV-induced DNA damage through two general strategies to repair the damaged nucleotides and to promote cell cycle progression in the presence of UV-damaged DNA. Defining the genetic pathways and understanding how they function together to enable effective tolerance to UV remains an important area of research. The structural maintenance of chromosomes (SMC) proteins form distinct complexes that maintain genome stability during chromosome segregation, homologous recombination, and DNA replication. Using a forward genetic screen, we identified two alleles of smc-5 that exacerbate UV sensitivity in Caenorhabditis elegans. Germ cells of smc-5-defective animals show reduced proliferation, sensitivity to perturbed replication, chromatin bridge formation, and accumulation of RAD-51 foci that indicate the activation of homologous recombination at DNA double-strand breaks. Mutations in the translesion synthesis polymerase polh-1 act synergistically with smc-5 mutations in provoking genome instability after UV-induced DNA damage. In contrast, the DNA damage accumulation and sensitivity of smc-5 mutant strains to replication impediments are suppressed by mutations in the C. elegans BRCA1/BARD1 homologs, brc-1 and brd-1. We propose that SMC-5/6 promotes replication fork stability and facilitates recombination-dependent repair when the BRC-1/BRD-1 complex initiates homologous recombination at stalled replication forks. Our data suggest that BRC-1/BRD-1 can both promote and antagonize genome stability depending on whether homologous recombination is initiated during DNA double-strand break repair or during replication stalling.
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99
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Abstract
In this issue of Molecular Cell, Chiba and colleagues (Matsuzawa et al., 2014) identify Obg-like ATPase 1 (OLA1) as an additional member of the BRCA1/BARD1/γ-tubulin complex that is critically involved in centrosome amplification and microtubule aster formation.
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Affiliation(s)
- Valenti Gomez
- UCL Cancer Institute, University College London, London WC1E 6BT, UK
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100
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Mathematical model of dynamic protein interactions regulating p53 protein stability for tumor suppression. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2013; 2013:358980. [PMID: 24454532 PMCID: PMC3888710 DOI: 10.1155/2013/358980] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 12/08/2013] [Accepted: 12/09/2013] [Indexed: 12/20/2022]
Abstract
In the field of cancer biology, numerous genes or proteins form extremely complex regulatory network, which determines cancer cell fate and cancer cell survival. p53 is a major tumor suppressor that is lost in more than 50% of human cancers. It has been well known that a variety of proteins regulate its protein stability, which is essential for its tumor suppressive function. It remains elusive how we could understand and target p53 stabilization process through network analysis. In this paper we discuss the use of random walk and stationary distribution to measure the compound effect of a network of genes or proteins. This method is applied to the network of nine proteins that influence the protein stability of p53 via regulating the interaction between p53 and its regulator MDM2. Our study identifies that some proteins such as HDAC1 in the network of p53 regulators may have more profound effects on p53 stability, agreeing with the established findings on HDAC1. This work shows the importance of using mathematical analysis to dissect the complexity of biology networks in cancer.
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