Science.gov

Sample records for gene brca1 dna

  1. Microelectronic DNA assay for the detection of BRCA1 gene mutations

    NASA Technical Reports Server (NTRS)

    Chen, Hua; Han, Jie; Li, Jun; Meyyappan, Meyya

    2004-01-01

    Mutations in BRCA1 are characterized by predisposition to breast cancer, ovarian cancer and prostate cancer as well as colon cancer. Prognosis for this cancer survival depends upon the stage at which cancer is diagnosed. Reliable and rapid mutation detection is crucial for the early diagnosis and treatment. We developed an electronic assay for the detection of a representative single nucleotide polymorphism (SNP), deletion and insertion in BRCA1 gene by the microelectronics microarray instrumentation. The assay is rapid, and it takes 30 minutes for the immobilization of target DNA samples, hybridization, washing and readout. The assay is multiplexing since it is carried out at the same temperature and buffer conditions for each step. The assay is also highly specific, as the signal-to-noise ratio is much larger than recommended value (72.86 to 321.05 vs. 5) for homozygotes genotyping, and signal ratio close to the perfect value 1 for heterozygotes genotyping (1.04).

  2. DNA Repair Genes ERCC1 and BRCA1 Expression in Non-Small Cell Lung Cancer Chemotherapy Drug Resistance

    PubMed Central

    Wang, Shuai; Liu, Feng; Zhu, Jingyan; Chen, Peng; Liu, Hongxing; Liu, Qi; Han, Junqing

    2016-01-01

    Background Surgery combined with chemotherapy is an important therapy for non-small cell lung cancer (NSCLC). However, chemotherapy drug resistance seriously hinders the curative effect. Studies show that DNA repair genes ERCC1 and BRCA1 are associated with NSCLC chemotherapy, but their expression and mechanism in NSCLC chemotherapy drug-resistant cells has not been elucidated. Material/Methods NSCLC cell line A549 and drug resistance cell line A549/DDP were cultured. Real-time PCR and Western blot analyses were used to detect ERCC1 and BRCA1 mRNA expression. A549/DDP cells were randomly divided into 3 groups: the control group; the siRNA-negative control group (scramble group); and the siRNA ERCC1 and BRCA1siRNA transfection group. Real-time PCR and Western blot analyses were used to determine ERCC1 and BRCA1 mRNA and protein expression. MTT was used to detect cell proliferation activity. Caspase 3 activity was tested by use of a kit. Western blot analysis was performed to detect PI3K, AKT, phosphorylated PI3K, and phosphorylated AKT protein expression. Results ERCC1 and BRCA1 were overexpressed in A549/DDP compared with A549 (P<0.05). ERCC1 and BRCA1siRNA transfection can significantly reduce ERCC1 and BRCA1 mRNA and protein expression (P<0.05). Downregulating ERCC1 and BRCA1 expression obviously inhibited cell proliferation and increased caspase 3 activity (P<0.05). Downregulating ERCC1 and BRCA1 significantly decreased PI3K and AKT phosphorylation levels (P<0.05). Conclusions ERCC1 and BRCA1 were overexpressed in NSCLC drug-resistant cells, and they regulated lung cancer occurrence and development through the phosphorylating PI3K/AKT signaling pathway. PMID:27289442

  3. DNA Repair Genes ERCC1 and BRCA1 Expression in Non-Small Cell Lung Cancer Chemotherapy Drug Resistance.

    PubMed

    Wang, Shuai; Liu, Feng; Zhu, Jingyan; Chen, Peng; Liu, Hongxing; Liu, Qi; Han, Junqing

    2016-01-01

    BACKGROUND Surgery combined with chemotherapy is an important therapy for non-small cell lung cancer (NSCLC). However, chemotherapy drug resistance seriously hinders the curative effect. Studies show that DNA repair genes ERCC1 and BRCA1 are associated with NSCLC chemotherapy, but their expression and mechanism in NSCLC chemotherapy drug-resistant cells has not been elucidated. MATERIAL AND METHODS NSCLC cell line A549 and drug resistance cell line A549/DDP were cultured. Real-time PCR and Western blot analyses were used to detect ERCC1 and BRCA1 mRNA expression. A549/DDP cells were randomly divided into 3 groups: the control group; the siRNA-negative control group (scramble group); and the siRNA ERCC1 and BRCA1siRNA transfection group. Real-time PCR and Western blot analyses were used to determine ERCC1 and BRCA1 mRNA and protein expression. MTT was used to detect cell proliferation activity. Caspase 3 activity was tested by use of a kit. Western blot analysis was performed to detect PI3K, AKT, phosphorylated PI3K, and phosphorylated AKT protein expression. RESULTS ERCC1 and BRCA1 were overexpressed in A549/DDP compared with A549 (P<0.05). ERCC1 and BRCA1siRNA transfection can significantly reduce ERCC1 and BRCA1 mRNA and protein expression (P<0.05). Downregulating ERCC1 and BRCA1 expression obviously inhibited cell proliferation and increased caspase 3 activity (P<0.05). Downregulating ERCC1 and BRCA1 significantly decreased PI3K and AKT phosphorylation levels (P<0.05). CONCLUSIONS ERCC1 and BRCA1 were overexpressed in NSCLC drug-resistant cells, and they regulated lung cancer occurrence and development through the phosphorylating PI3K/AKT signaling pathway. PMID:27289442

  4. Color bar coding the BRCA1 gene on combed DNA: a useful strategy for detecting large gene rearrangements.

    PubMed

    Gad, S; Aurias, A; Puget, N; Mairal, A; Schurra, C; Montagna, M; Pages, S; Caux, V; Mazoyer, S; Bensimon, A; Stoppa-Lyonnet, D

    2001-05-01

    Genetic linkage data have shown that alterations of the BRCA1 gene are responsible for the majority of hereditary breast and ovarian cancers. BRCA1 germline mutations, however, are found less frequently than expected. Mutation detection strategies, which are generally based on the polymerase chain reaction, therefore focus on point and small gene alterations. These approaches do not allow for the detection of large gene rearrangements, which also can be involved in BRCA1 alterations. Indeed, a few of them, spread over the entire BRCA1 gene, have been detected recently by Southern blotting or transcript analysis. We have developed an alternative strategy allowing a panoramic view of the BRCA1 gene, based on dynamic molecular combing and the design of a full four-color bar code of the BRCA1 region. The strategy was tested with the study of four large BRCA1 rearrangements previously reported. In addition, when screening a series of 10 breast and ovarian cancer families negatively tested for point mutation in BRCA1/2, we found an unreported 17-kb BRCA1 duplication encompassing exons 3 to 8. The detection of rearrangements as small as 2 to 6 kb with respect to the normal size of the studied fragment is achieved when the BRCA1 region is divided into 10 fragments. In addition, as the BRCA1 bar code is a morphologic approach, the direct observation of complex and likely underreported rearrangements, such as inversions and insertions, becomes possible. PMID:11284038

  5. BRCA1 and BRCA2 gene testing

    MedlinePlus

    ... gov/ency/patientinstructions/000690.htm BRCA1 and BRCA2 gene testing To use the sharing features on this ... br east ca ncer. What is the BRCA Gene Mutation? BRCA1 and BRCA2 are genes that suppress ...

  6. BRCA1-mediated repression of select X chromosome genes.

    PubMed

    Jazaeri, Amir A; Chandramouli, Gadisetti VR; Aprelikova, Olga; Nuber, Ulrike A; Sotiriou, Christos; Liu, Edison T; Ropers, H Hilger; Yee, Cindy J; Boyd, Jeff; Barrett, J Carl

    2004-09-21

    Recently BRCA1 has been implicated in the regulation of gene expression from the X chromosome. In this study the influence of BRCA1 on expression of X chromosome genes was investigated. Complementary DNA microarrays were used to compare the expression levels of X chromosome genes in 18 BRCA1-associated ovarian cancers to those of the 13 "BRCA1-like" and 14 "BRCA2-like" sporadic tumors (as defined by previously reported expression profiling). Significance was determined using parametric statistics with P < 0.005 as a cutoff. Forty of 178 total X-chromosome transcripts were differentially expressed between the BRCA1-associated tumors and sporadic cancers with a BRCA2-like molecular profile. Thirty of these 40 genes showed higher mean expression in the BRCA1-associated samples including all 11 transcripts that mapped to Xp11. In contrast, four of 178 total X chromosome transcripts showed significant differential expression between BRCA1-associated and sporadic tumors with a BRCA1-like molecular profile. All four mapped to Xp11 and showed higher mean expression in BRCA1-associated tumors. Re-expression of BRCA1 in HCC1937 BRCA1-deficient breast cancer cell resulted in the repression of 21 transcripts. Eleven of the 21 (54.5%) transcripts mapped to Xp11. However, there was no significant overlap between these Xp11 genes and those found to be differentially expressed between BRCA1-associated and sporadic ovarian cancer samples. These results demonstrate that BRCA1 mediates the repression of several X chromosome genes, many of which map to the Xp11 locus. PMID:15383145

  7. Breast cancer risk and the DNA double-strand break end-joining capacity of nonhomologous end-joining genes are affected by BRCA1.

    PubMed

    Bau, Da-Tian; Fu, Yi-Ping; Chen, Shou-Tung; Cheng, Ting-Chih; Yu, Jyh-Cherng; Wu, Pei-Ei; Shen, Chen-Yang

    2004-07-15

    A tumorigenic role of the nonhomologous end-joining (NHEJ) pathway for the repair of DNA double-strand breaks (DSBs) has been suggested by the finding of a significant association between increased breast cancer risk and a cooperative effect of single nucleotide polymorphisms (SNPs) in NHEJ genes. However, the lack of an association between hereditary breast cancer and defective NHEJ genes prevents conclusions from being drawn about a link between NHEJ and breast cancer development. Recently, BRCA1-deficient mouse embryonic fibroblasts were found to have significantly reduced NHEJ activity, suggesting an accessory role of BRCA1 in NHEJ. The present study was performed to confirm this observation in human breast cancer cell lines and to examine whether the interaction between BRCA1 and NHEJ was of tumorigenic significance. Support for this hypothesis came from the findings that (a) a case-control study (469 breast cancer patients and 740 healthy controls) showed that the breast cancer risk associated with high-risk genotypes of NHEJ genes was significantly modified by the BRCA1 genotype. A significant increase in the cancer risk associated either with harboring one additional putative high-risk NHEJ genotype or with the joint effect of having reproductive risk factors (reflected by an interval of > or =12 years between menarche and first full-term pregnancy) and a higher number of high-risk genotypes of the NHEJ genes was only seen in women with at least one variant BRCA1 allele (i.e., the Glu/Gly or Gly/Gly forms of BRCA1 Glu(1038)Gly); and (b) a phenotype-based study measuring in vitro and in vivo NHEJ capacity showed that the precise end-joining capacity was different in breast cancer cell lines with different BRCA1 statuses being higher in BRCA1-expressing MCF-7 cells than in HCC1937 cells (defective BRCA1 expression). Furthermore, this end-joining capacity was decreased in MCF-7 cells in which BRCA1 expression was blocked using small interfering RNA and

  8. BRCA1 in the DNA damage response and at telomeres

    PubMed Central

    Rosen, Eliot M.

    2013-01-01

    Mutations of the breast and ovarian cancer susceptibility gene 1 (BRCA1) account for about 40–45% of hereditary breast cancer cases. Moreover, a significant fraction of sporadic (non-hereditary) breast and ovarian cancers exhibit reduced or absent expression of the BRCA1 protein, suggesting an additional role for BRCA1 in sporadic cancers. BRCA1 follows the classic pattern of a highly penetrant Knudsen-type tumor suppressor gene in which one allele is inactivated through a germ-line mutation and the other is mutated or deleted within the tumor. BRCA1 is a multi-functional protein but it is not fully understood which function(s) is (are) most important for tumor suppression, nor is it clear why BRCA1-mutations confer a high risk for breast and ovarian cancers and not a broad spectrum of tumor types. Here, we will review BRCA1 functions in the DNA damage response (DDR), which are likely to contribute to tumor suppression. In the process, we will highlight some of the controversies and unresolved issues in the field. We will also describe a recently identified and under-investigated role for BRCA1 in the regulation of telomeres and the implications of this role in the DDR and cancer suppression. PMID:23802008

  9. BRCA1 and BRCA2 gene testing

    MedlinePlus

    The BRCA1 and BRCA2 gene test is a blood test that can tell you if you have a higher risk of getting cancer. The name ... BRCA1 and BRCA2 are genes that suppress malignant tumors (cancer) in ... change (become mutated) they do not suppress tumors like they ...

  10. MERIT40 facilitates BRCA1 localization and DNA damage repair

    PubMed Central

    Feng, Lin; Huang, Jun; Chen, Junjie

    2009-01-01

    The product of breast cancer susceptibility gene 1, BRCA1, plays pivotal roles in the maintenance of genomic integrity. Mounting evidence indicates that BRCA1 associates with many proteins or protein complexes to regulate diverse processes important for the cellular response to DNA damage. One of these complexes, which mediates the accumulation of BRCA1 at sites of DNA breaks, involves the ubiquitin-binding motif (UIM)-containing protein RAP80, a coiled-coil domain protein CCDC98/Abraxas, and a deubiquitinating enzyme BRCC36. Here we describe the characterization of a novel component of this complex, MERIT40 (Mediator of Rap80 Interactions and Targeting 40 kd), which together with an adaptor protein BRE/BRCC45, enforces the BRCA1-dependent DNA damage response. MERIT40 is assembled into this RAP80/CCDC98-containing complex via its direct interaction with BRE/BRCC45. Importantly, MERIT40 regulates BRCA1 retention at DNA breaks and checkpoint function primarily via a role in maintaining the stability of BRE and this five-subunit protein complex at sites of DNA damage. Together, our study reveals that a stable complex containing MERIT40 acts early in DNA damage response and regulates damage-dependent BRCA1 localization. PMID:19261748

  11. DNA repair genes implicated in triple negative familial non-BRCA1/2 breast cancer predisposition

    PubMed Central

    Ollier, Marie; Radosevic-Robin, Nina; Kwiatkowski, Fabrice; Ponelle, Flora; Viala, Sandrine; Privat, Maud; Uhrhammer, Nancy; Bernard-Gallon, Dominique; Penault-Llorca, Frédérique; Bignon, Yves-Jean; Bidet, Yannick

    2015-01-01

    Among breast cancers, 10 to 15% of cases would be due to hereditary risk. In these familial cases, mutations in BRCA1 and BRCA2 are found in only 15% to 20%, meaning that new susceptibility genes remain to be found. Triple-negative breast cancers represent 15% of all breast cancers, and are generally aggressive tumours without targeted therapies available. Our hypothesis is that some patients with triple negative breast cancer could share a genetic susceptibility different from other types of breast cancers. We screened 36 candidate genes, using pyrosequencing, in all the 50 triple negative breast cancer patients with familial history of cancer but no BRCA1 or BRCA2 mutation of a population of 3000 families who had consulted for a familial breast cancer between 2005 and 2013. Any mutations were also sequenced in available relatives of cases. Protein expression and loss of heterozygosity were explored in tumours. Seven deleterious mutations in 6 different genes (RAD51D, MRE11A, CHEK2, MLH1, MSH6, PALB2) were observed in one patient each, except the RAD51D mutation found in two cases. Loss of heterozygosity in the tumour was found for 2 of the 7 mutations. Protein expression was absent in tumour tissue for 5 mutations. Taking into consideration a specific subtype of tumour has revealed susceptibility genes, most of them in the homologous recombination DNA repair pathway. This may provide new possibilities for targeted therapies, along with better screening and care of patients. PMID:26328243

  12. Modification of BRCA1-Associated Breast and Ovarian Cancer Risk by BRCA1 Interacting Genes

    PubMed Central

    Rebbeck, Timothy R.; Mitra, Nandita; Domchek, Susan M.; Wan, Fei; Friebel, Tara M.; Tran, Teo V.; Singer, Christian F.; Tea, Muy-Kheng Maria; Blum, Joanne L.; Tung, Nadine; Olopade, Olufunmilayo I.; Weitzel, Jeffrey N.; Lynch, Henry T.; Snyder, Carrie L.; Garber, Judy E.; Antoniou, Antonis C.; Peock, Susan; Evans, D. Gareth; Paterson, Joan; Kennedy, M. John; Donaldson, Alan; Dorkins, Huw; Easton, Douglas F.; Rubinstein, Wendy S.; Daly, Mary B.; Isaacs, Claudine; Nevanlinna, Heli; Couch, Fergus J.; Andrulis, Irene L.; Freidman, Eitan; Laitman, Yael; Ganz, Patricia A.; Tomlinson, Gail E.; Neuhausen, Susan L.; Narod, Steven A.; Phelan, Catherine M.; Greenberg, Roger; Nathanson, Katherine L.

    2011-01-01

    Inherited BRCA1 mutations confer elevated breast cancer risk. Recent studies have identified genes that encode proteins that interact with BRCA1 as modifiers of BRCA1-associated breast cancer. We evaluated a comprehensive set of genes that encode most known BRCA1 interactors to evaluate the role of these genes as modifiers of cancer risk. A cohort of 2,825 BRCA1 mutation carriers was used to evaluate the association of haplotypes at ATM, BRCC36, BRCC45 (BRE), BRIP1 (BACH1/FANCJ), CTIP, ABRA1 (FAM175A), MERIT40, MRE11A, NBS1, PALB2 (FANCN), RAD50, RAD51, RAP80, TOPBP1 and time to breast and ovarian cancer diagnosis. False Discovery Rate (FDR) adjusted p-value for overall association of haplotypes (pFDR) with breast cancer were identified at ATM (pFDR =0.029), BRCC45 (pFDR=0.0.19), BRIP1 (pFDR =0.008), CTIP (pFDR =0.017), MERIT40 (pFDR =0.019), NBS1 (pFDR=0.003), RAD50 (pFDR=0.014), and TOPBP1 (pFDR =0.011) and were associated with breast cancer risk. Haplotypes at ABRA1 (pFDR=0.007), BRCC45 (pFDR=0.016 and pFDR=0.005 in two haplotype blocks) and RAP80 (pFDR<0.001) were associated with ovarian cancer risk. Overall, the data suggest that genomic variation at multiple loci that encode proteins that interact biologically with BRCA1 are associated with modified breast cancer and ovarian cancer risk in women who carry BRCA1 mutations. PMID:21799032

  13. Physical mapping, cloning, and identification of genes within a 500-kb region containing BRCA1.

    PubMed Central

    Brown, M A; Jones, K A; Nicolai, H; Bonjardim, M; Black, D; McFarlane, R; de Jong, P; Quirk, J P; Lehrach, H; Solomon, E

    1995-01-01

    BRCA1 is a breast/ovarian cancer susceptibility gene on human chromosome 17q21. We describe a complete and detailed physical map of a 500-kb region of genomic DNA containing the BRCA1 gene and the partial cloning in phage P1 artificial chromosomes. Approximately 70 exons were isolated from this region, 11 of which were components of the BRCA1 gene. Analysis of the other exons revealed a rho-related G protein and the interferon-induced leucine-zipper protein IFP-35. Images Fig. 1 Fig. 2 Fig. 4 PMID:7753812

  14. Growth Retardation, DNA Repair Defects, and Lack of Spermatogenesis in BRCA1-Deficient Mice

    PubMed Central

    Cressman, Victoria L.; Backlund, Dana C.; Avrutskaya, Anna V.; Leadon, Steven A.; Godfrey, Virginia; Koller, Beverly H.

    1999-01-01

    BRCA1 is a nuclear phosphoprotein expressed in a broad spectrum of tissues during cell division. The inheritance of a mutant BRCA1 allele dramatically increases a woman’s lifetime risk for developing both breast and ovarian cancers. A number of mouse lines carrying mutations in the Brca1 gene have been generated, and mice homozygous for these mutations generally die before day 10 of embryonic development. We report here the survival of a small number of mice homozygous for mutations in both the p53 and Brca1 genes. The survival of these mice is likely due to additional unknown mutations or epigenetic effects. Analysis of the Brca1−/− p53−/− animals indicates that BRCA1 is not required for the development of most organ systems. However, these mice are growth retarded, males are infertile due to meiotic failure, and the mammary gland of the female mouse is underdeveloped. Growth deficiency due to loss of BRCA1 was more thoroughly examined in an analysis of primary fibroblast lines obtained from these animals. Like p53−/− fibroblasts, Brca1−/− p53−/− cells proliferate more rapidly than wild-type cells; however, a high level of cellular death in these cultures results in reduced overall growth rates in comparison to p53−/− fibroblasts. Brca1−/− p53−/− fibroblasts are also defective in transcription-coupled repair and display increased sensitivity to DNA-damaging agents. We show, however, that after continued culture, and perhaps accelerated by the loss of BRCA1 repair functions, populations of Brca1−/− p53−/− fibroblasts with increased growth rates can be isolated. The increased survival of BRCA1-deficient fibroblasts in the absence of p53, and with the subsequent accumulation of additional growth-promoting changes, may mimic the events that occur during malignant transformation of BRCA1-deficient epithelia. PMID:10490643

  15. Unsolved mystery: the role of BRCA1 in DNA end-joining

    PubMed Central

    Saha, Janapriya; Davis, Anthony J.

    2016-01-01

    Heritable mutations in the tumor suppressor gene BRCA1 increase a woman's lifetime risk of developing breast and ovarian cancer. BRCA1's tumor suppressor function is directly linked to its myriad of functions in the cellular response to DNA double-strand breaks (DSBs). BRCA1 interacts with an extensive array of DNA damage responsive proteins and plays important roles in DSB repair, mediated by the homologous recombination pathway, and in the activation of cell cycle checkpoints. However, the role of BRCA1 in the other two DSB repair pathways, classical non-homologous end-joining (C-NHEJ) and alternative NHEJ (A-NHEJ), remains unclear. In this review, we will discuss the current literature on BRCA1's potential role(s) in modulating both C-NHEJ and A-NHEJ. We also present a model showing that BRCA1 contributes to genomic maintenance by promoting precise DNA repair across all cell cycle phases via the direct modulation of DNA end-joining. PMID:27170701

  16. Detection of a novel mutation in exon 20 of the BRCA1 gene.

    PubMed

    Chakraborty, Abhijit; Katarkar, Atul; Chaudhuri, Keya; Mukhopadhyay, Ashis; Basak, Jayasri

    2013-12-01

    Hereditary breast cancer constitutes 5-10% of all breast cancer cases. Inherited mutations in the BRCA1 and BRCA2 tumor-suppressor genes account for the majority of hereditary breast cancer cases. The BRCA1 C-terminal region (BRCT) has a functional duplicated globular domain, which helps with DNA damage repair and cell cycle checkpoint protein control. More than 100 distinct BRCA1 missense variants with structural and functional effects have been documented within the BRCT domain. Interpreting the results of mutation screening of tumor-suppressor genes that can have high-risk susceptibility mutations is increasingly important in clinical practice. This study includes a novel mutation, p.His1746 Pro (c.5237A>C), which was found in BRCA1 exon 20 of a breast cancer patient. In silico analysis suggests that this mutation could alter the stability and orientation of the BRCT domain and the differential binding of the BACH1 substrate. PMID:24297685

  17. BRCA1 Gene Mutation Screening for the Hereditary Breast and/or Ovarian Cancer Syndrome in Breast Cancer Cases: a First High Resolution DNA Melting Analysis in Indonesia.

    PubMed

    Mundhofir, Farmaditya Ep; Wulandari, Catharina Endah; Prajoko, Yan Wisnu; Winarni, Tri Indah

    2016-01-01

    Specific patterns of the hereditary breast and ovarian cancer (HBOC) syndrome are related to mutations in the BRCA1 gene. One hundred unrelated breast cancer patients were interviewed to obtain clinical symptoms and signs, pedigree and familial history of HBOC syndrome related cancer. Subsequently, data were calculated using the Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA) risk prediction model. Patients with high score of BOADICEA were offered genetic testing. Eleven patients with high score of BOADICEA, 2 patients with low score of BOADICEA, 2 patient's family members and 15 controls underwent BRCA1 genetic testing. Mutation screening using PCR-HRM was carried out in 22 exons (41 amplicons) of BRCA1 gene. Sanger sequencing was subjected in all samples with aberrant graph. This study identified 10 variants in the BRCA1 gene, consisting of 6 missense mutations (c.1480C>A, c.2612C>T, c.2566T>C, c.3113A>G, c.3548 A>G, c.4837 A>G), 3 synonymous mutations (c.2082 C> T, c.2311 T> C and c.4308T>C) and one intronic mutation (c.134+35 G>T). All variants tend to be polymorphisms and unclassified variants. However, no known pathogenic mutations were found. PMID:27039803

  18. BRCA1/BARD1 orthologs required for DNA repair in Caenorhabditis elegans.

    PubMed

    Boulton, Simon J; Martin, Julie S; Polanowska, Jolanta; Hill, David E; Gartner, Anton; Vidal, Marc

    2004-01-01

    Inherited germline mutations in the tumor suppressor gene BRCA1 predispose individuals to early onset breast and ovarian cancer. BRCA1 together with its structurally related partner BARD1 is required for homologous recombination and DNA double-strand break repair, but how they perform these functions remains elusive. As part of a comprehensive search for DNA repair genes in C. elegans, we identified a BARD1 ortholog. In protein interaction screens, Ce-BRD-1 was found to interact with components of the sumoylation pathway, the TACC domain protein TAC-1, and most importantly, a homolog of mammalian BRCA1. We show that animals depleted for either Ce-brc-1 or Ce-brd-1 display similar abnormalities, including a high incidence of males, elevated levels of p53-dependent germ cell death before and after irradiation, and impaired progeny survival and chromosome fragmentation after irradiation. Furthermore, depletion of ubc-9 and tac-1 leads to radiation sensitivity and a high incidence of males, respectively, potentially linking these genes to the C. elegans BRCA1 pathway. Our findings support a shared role for Ce-BRC-1 and Ce-BRD-1 in C. elegans DNA repair processes, and this role will permit studies of the BRCA1 pathway in an organism amenable to rapid genetic and biochemical analysis. PMID:14711411

  19. Identification of BRCA1/2 Founder Mutations in Southern Chinese Breast Cancer Patients Using Gene Sequencing and High Resolution DNA Melting Analysis

    PubMed Central

    Kwong, Ava; Ng, Enders Kai On; Wong, Chris Lei Po; Law, Fian Bic Fai; Au, Tommy; Wong, Hong Nei; Kurian, Allison W.; West, Dee W.; Ford, James M.; Ma, Edmond Siu Kwan

    2012-01-01

    Background Ethnic variations in breast cancer epidemiology and genetics have necessitated investigation of the spectra of BRCA1 and BRCA2 mutations in different populations. Knowledge of BRCA mutations in Chinese populations is still largely unknown. We conducted a multi-center study to characterize the spectra of BRCA mutations in Chinese breast and ovarian cancer patients from Southern China. Methodology/Principal Findings A total of 651 clinically high-risk breast and/or ovarian cancer patients were recruited from the Hong Kong Hereditary Breast Cancer Family Registry from 2007 to 2011. Comprehensive BRCA1 and BRCA2 mutation screening was performed using bi-directional sequencing of all coding exons of BRCA1 and BRCA2. Sequencing results were confirmed by in-house developed full high resolution DNA melting (HRM) analysis. Among the 451 probands analyzed, 69 (15.3%) deleterious BRCA mutations were identified, comprising 29 in BRCA1 and 40 in BRCA2. The four recurrent BRCA1 mutations (c.470_471delCT, c.3342_3345delAGAA, c.5406+1_5406+3delGTA and c.981_982delAT) accounted for 34.5% (10/29) of all BRCA1 mutations in this cohort. The four recurrent BRCA2 mutations (c.2808_2811delACAA, c.3109C>T, c.7436_7805del370 and c.9097_9098insA) accounted for 40% (16/40) of all BRCA2 mutations. Haplotype analysis was performed to confirm 1 BRCA1 and 3 BRCA2 mutations are putative founder mutations. Rapid HRM mutation screening for a panel of the founder mutations were developed and validated. Conclusion In this study, our findings suggest that BRCA mutations account for a substantial proportion of hereditary breast/ovarian cancer in Southern Chinese population. Knowing the spectrum and frequency of the founder mutations in this population will assist in the development of a cost-effective rapid screening assay, which in turn facilitates genetic counseling and testing for the purpose of cancer risk assessment. PMID:22970155

  20. Regulated recruitment of tumor suppressor BRCA1 to the p21 gene by coactivator methylation

    PubMed Central

    Lee, Young-Ho; Bedford, Mark T.; Stallcup, Michael R.

    2011-01-01

    Tumor suppression by p53 and BRCA1 involves regulation of cell cycle, apoptosis, and DNA repair and is influenced by transcriptional coactivators and post-translational modifications. Here we show that coactivator-associated arginine methyltransferase 1 (CARM1) methylates Arg 754 in the KIX region of coactivator p300. Methylated p300 and p300 protein fragments are preferentially recognized by BRCT domains of BRCA1, identifying the BRCT domain as a novel methylarginine-binding module. CARM1 and p300 cooperate with BRCA1 and p53 to induce expression of the critical cell cycle and proliferation regulator p21WAF1/CIP1 in response to DNA damage. This induction was severely attenuated by elimination of CARM1 or its methyltransferase activity, or by mutation of Arg 754 of p300. Absence of CARM1 methyltransferase activity led to failure of cells to arrest in the G1 phase of the cell cycle in response to DNA damage. CARM1 methyltransferase activity was required for induction of some p53 target genes (p21 and Gadd45) but not others (Bax) by DNA damage. Recruitment of BRCA1 to the p53-binding region of the p21 promoter in response to DNA damage required methylation of Arg 754 of p300 by CARM1. Thus, coactivator methylation may be crucial for fine-tuning the tumor suppressor function of BRCA1 and other BRCT domain proteins. PMID:21245169

  1. Targeting BRCA1-BER deficient breast cancer by ATM or DNA-PKcs blockade either alone or in combination with cisplatin for personalized therapy.

    PubMed

    Albarakati, Nada; Abdel-Fatah, Tarek M A; Doherty, Rachel; Russell, Roslin; Agarwal, Devika; Moseley, Paul; Perry, Christina; Arora, Arvind; Alsubhi, Nouf; Seedhouse, Claire; Rakha, Emad A; Green, Andrew; Ball, Graham; Chan, Stephen; Caldas, Carlos; Ellis, Ian O; Madhusudan, Srinivasan

    2015-01-01

    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. PMID:25205036

  2. Genetic suppression reveals DNA repair-independent antagonism between BRCA1 and COBRA1 in mammary gland development.

    PubMed

    Nair, Sreejith J; Zhang, Xiaowen; Chiang, Huai-Chin; Jahid, Md Jamiul; Wang, Yao; Garza, Paula; April, Craig; Salathia, Neeraj; Banerjee, Tapahsama; Alenazi, Fahad S; Ruan, Jianhua; Fan, Jian-Bing; Parvin, Jeffrey D; Jin, Victor X; Hu, Yanfen; Li, Rong

    2016-01-01

    The breast cancer susceptibility gene BRCA1 is well known for its function in double-strand break (DSB) DNA repair. While BRCA1 is also implicated in transcriptional regulation, the physiological significance remains unclear. COBRA1 (also known as NELF-B) is a BRCA1-binding protein that regulates RNA polymerase II (RNAPII) pausing and transcription elongation. Here we interrogate functional interaction between BRCA1 and COBRA1 during mouse mammary gland development. Tissue-specific deletion of Cobra1 reduces mammary epithelial compartments and blocks ductal morphogenesis, alveologenesis and lactogenesis, demonstrating a pivotal role of COBRA1 in adult tissue development. Remarkably, these developmental deficiencies due to Cobra1 knockout are largely rescued by additional loss of full-length Brca1. Furthermore, Brca1/Cobra1 double knockout restores developmental transcription at puberty, alters luminal epithelial homoeostasis, yet remains deficient in homologous recombination-based DSB repair. Thus our genetic suppression analysis uncovers a previously unappreciated, DNA repair-independent function of BRCA1 in antagonizing COBRA1-dependent transcription programme during mammary gland development. PMID:26941120

  3. Genetic suppression reveals DNA repair-independent antagonism between BRCA1 and COBRA1 in mammary gland development

    PubMed Central

    Nair, Sreejith J.; Zhang, Xiaowen; Chiang, Huai-Chin; Jahid, Md Jamiul; Wang, Yao; Garza, Paula; April, Craig; Salathia, Neeraj; Banerjee, Tapahsama; Alenazi, Fahad S.; Ruan, Jianhua; Fan, Jian-Bing; Parvin, Jeffrey D.; Jin, Victor X.; Hu, Yanfen; Li, Rong

    2016-01-01

    The breast cancer susceptibility gene BRCA1 is well known for its function in double-strand break (DSB) DNA repair. While BRCA1 is also implicated in transcriptional regulation, the physiological significance remains unclear. COBRA1 (also known as NELF-B) is a BRCA1-binding protein that regulates RNA polymerase II (RNAPII) pausing and transcription elongation. Here we interrogate functional interaction between BRCA1 and COBRA1 during mouse mammary gland development. Tissue-specific deletion of Cobra1 reduces mammary epithelial compartments and blocks ductal morphogenesis, alveologenesis and lactogenesis, demonstrating a pivotal role of COBRA1 in adult tissue development. Remarkably, these developmental deficiencies due to Cobra1 knockout are largely rescued by additional loss of full-length Brca1. Furthermore, Brca1/Cobra1 double knockout restores developmental transcription at puberty, alters luminal epithelial homoeostasis, yet remains deficient in homologous recombination-based DSB repair. Thus our genetic suppression analysis uncovers a previously unappreciated, DNA repair-independent function of BRCA1 in antagonizing COBRA1-dependent transcription programme during mammary gland development. PMID:26941120

  4. Functional variant analyses (FVAs) predict pathogenicity in the BRCA1 DNA double-strand break repair pathway.

    PubMed

    Loke, Johnny; Pearlman, Alexander; Upadhyay, Kinnari; Tesfa, Lydia; Shao, Yongzhao; Ostrer, Harry

    2015-06-01

    Heritable mutations in the BRCA1 and BRCA2 and other genes in the DNA double-strand break (DSB) repair pathway disrupt binding of the encoded proteins, transport into the nucleus and initiation of homologous recombination, thereby increasing cancer risk [Scully, R., Chen, J., Plug, A., Xiao, Y., Weaver, D., Feunteun, J., Ashley, T. and Livingston, D.M. (1997) Association of BRCA1 with Rad51 in mitotic and meiotic cells. Cell, 88, 265-275, Chen, J., Silver, D.P., Walpita, D., Cantor, S.B., Gazdar, A.F., Tomlinson, G., Couch, F.J., Weber, B.L., Ashley, T., Livingston, D.M. et al. (1998) Stable interaction between the products of the BRCA1 and BRCA2 tumor suppressor genes in mitotic and meiotic cells. Mol. Cell, 2, 317-328]. To meet the challenge of correct classification, flow cytometry-based functional variant analyses (FVAs) were developed to determine whether variants in DSB repair genes disrupted the binding of BRCA1 to BARD1, PALB2, BRCA2 and FANCD2, phosphorylation of p53 or BRCA1 nuclear localization in response to DNA damage caused by diepoxybutane, mitomycin C and bleomycin. Lymphoblastoid cells from individuals with BRCA1 pathogenic mutations, benign variants, and variants of uncertain significance or with known BRCA2, FANCC or NBN mutations were tested. Mutations in BRCA1 decreased nuclear localization of BRCA1 in response to individual or combination drug treatment. Mutations in BRCA1 reduced binding to co-factors, PALB2 and FANCD2 and decreased phosphorylation of p53. Mutations in BRCA2, FANCC and NBN decreased nuclear localization of BRCA1 in response to drug treatment, cofactors binding and p53 phosphorylation. Unsupervised cluster analysis of all and as few as two assays demonstrated two apparent clusters, high-risk BRCA1 mutations and phenocopies and low-risk, fully sequenced controls and variants of uncertain significance (VUS). Thus, two FVA assays distinguish BRCA1 mutations and phenocopies from benign variants and categorize most VUS as benign

  5. DNA methylation profiling to assess pathogenicity of BRCA1 unclassified variants in breast cancer

    PubMed Central

    Flower, Kirsty J; Shenker, Natalie S; El-Bahrawy, Mona; Goldgar, David E; Parsons, Michael T; Spurdle, Amanda B; Morris, Joanna R; Brown, Robert; Flanagan, James M

    2015-01-01

    Germline pathogenic mutations in BRCA1 increase risk of developing breast cancer. Screening for mutations in BRCA1 frequently identifies sequence variants of unknown pathogenicity and recent work has aimed to develop methods for determining pathogenicity. We previously observed that tumor DNA methylation can differentiate BRCA1-mutated from BRCA1-wild type tumors. We hypothesized that we could predict pathogenicity of variants based on DNA methylation profiles of tumors that had arisen in carriers of unclassified variants. We selected 150 FFPE breast tumor DNA samples [47 BRCA1 pathogenic mutation carriers, 65 BRCAx (BRCA1-wild type), 38 BRCA1 test variants] and analyzed a subset (n=54) using the Illumina 450K methylation platform, using the remaining samples for bisulphite pyrosequencing validation. Three validated markers (BACH2, C8orf31, and LOC654342) were combined with sequence bioinformatics in a model to predict pathogenicity of 27 variants (independent test set).  Predictions were compared with standard multifactorial likelihood analysis. Prediction was consistent for c.5194-12G>A (IVS 19-12 G>A) (P>0.99); 13 variants were considered not pathogenic or likely not pathogenic using both approaches. We conclude that tumor DNA methylation data alone has potential to be used in prediction of BRCA1 variant pathogenicity but is not independent of estrogen receptor status and grade, which are used in current multifactorial models to predict pathogenicity. PMID:26727311

  6. Discordant pattern of BRCA1 gene epimutation in blood between mothers and daughters.

    PubMed

    Wojdacz, Tomasz K; Harari, Florencia; Vahter, Marie; Broberg, Karin

    2015-07-01

    Methylation of the promoter of BRCA1 gene in peripheral blood (epimutation) has been associated with increased risk for breast cancer. Some studies have indicated that this epimutation is of constitutional origin and hence it could potentially be transmitted across generations. We used methylation sensitive high resolution melting technique to measure methylation of BRCA1 promoter in blood samples from 226 healthy women from the Andean region in Salta province, northern Argentina. In total 29 (13%) of the women showed detectable methylation of this gene. The analyses of mother-daughter pairs in this study, showed discordant methylation of BRCA1 between generations, with mothers tested positive for BRCA1 methylation in blood having daughters without signs of BRCA1 methylation, and vice versa. Our results show that the BRCA1 epimutation is unlikely transmitted from mother to daughters and hence may be a consequence of environmental exposure. PMID:25878326

  7. Breast cancer 1 (BRCA1)-deficient embryos develop normally but are more susceptible to ethanol-initiated DNA damage and embryopathies☆

    PubMed Central

    Shapiro, Aaron M.; Miller-Pinsler, Lutfiya; Wells, Peter G.

    2015-01-01

    The breast cancer 1 (brca1) gene is associated with breast and ovarian cancers, and heterozygous (+/−) brca1 knockout progeny develop normally, suggesting a negligible developmental impact. However, our results show BRCA1 plays a broader biological role in protecting the embryo from oxidative stress. Sox2-promoted Cre-expressing hemizygous males were mated with floxed brca1 females, and gestational day 8 +/− brca1 conditional knockout embryos with a 28% reduction in protein expression were exposed in culture to the reactive oxygen species (ROS)-initiating drug ethanol (EtOH). Untreated +/− brca1-deficient embryos developed normally, but when exposed to EtOH exhibited increased levels of oxidatively damaged DNA, measured as 8-oxo-2'-deoxyguanosine, γH2AX, which is a marker of DNA double strand breaks that can result from 8-oxo-2'-deoxyguanosine, formation, and embryopathies at EtOH concentrations that did not affect their brca1-normal littermates. These results reveal that even modest BRCA1 deficiencies render the embryo more susceptible to drug-enhanced ROS formation, and corroborate a role for DNA oxidation in the mechanism of EtOH teratogenesis. PMID:26629949

  8. Human BRCA1-BARD1 ubiquitin ligase activity counteracts chromatin barriers to DNA resection.

    PubMed

    Densham, Ruth M; Garvin, Alexander J; Stone, Helen R; Strachan, Joanna; Baldock, Robert A; Daza-Martin, Manuel; Fletcher, Alice; Blair-Reid, Sarah; Beesley, James; Johal, Balraj; Pearl, Laurence H; Neely, Robert; Keep, Nicholas H; Watts, Felicity Z; Morris, Joanna R

    2016-07-01

    The opposing activities of 53BP1 and BRCA1 influence pathway choice in DNA double-strand-break repair. How BRCA1 counteracts the inhibitory effect of 53BP1 on DNA resection and homologous recombination is unknown. Here we identify the site of BRCA1-BARD1 required for priming ubiquitin transfer from E2∼ubiquitin and demonstrate that BRCA1-BARD1's ubiquitin ligase activity is required for repositioning 53BP1 on damaged chromatin. We confirm H2A ubiquitination by BRCA1-BARD1 and show that an H2A-ubiquitin fusion protein promotes DNA resection and repair in BARD1-deficient cells. BRCA1-BARD1's function in homologous recombination requires the chromatin remodeler SMARCAD1. SMARCAD1 binding to H2A-ubiquitin and optimal localization to sites of damage and activity in DNA repair requires its ubiquitin-binding CUE domains. SMARCAD1 is required for 53BP1 repositioning, and the need for SMARCAD1 in olaparib or camptothecin resistance is alleviated by 53BP1 loss. Thus, BRCA1-BARD1 ligase activity and subsequent SMARCAD1-dependent chromatin remodeling are critical regulators of DNA repair. PMID:27239795

  9. Understanding missense mutations in the BRCA1 gene: An evolutionary approach

    PubMed Central

    Fleming, Melissa A.; Potter, John D.; Ramirez, Christina J.; Ostrander, Gary K.; Ostrander, Elaine A.

    2003-01-01

    The role of missense changes in BRCA1 in breast cancer susceptibility has been difficult to establish. We used comparative evolutionary methods to identify potential functionally important amino acid sites in exon 11 and missense changes likely to disrupt gene function, aligning sequences from 57 eutherian mammals and categorizing amino acid sites by degree of conservation. We used Bayesian phylogenetic analyses to determine relationships among orthologs and identify codons evolving under positive selection. Most conserved residues occur in a region with the highest concentration of protein-interacting domains. Rapidly evolving residues are concentrated in the RAD51-interacting domain, suggesting that selection is acting most strongly on the role of BRCA1 in DNA repair. Investigation of the functional role of missense changes in breast-cancer susceptibility should focus on 38 missense changes in conserved and 3 in rapidly evolving regions of exon 11. PMID:12531920

  10. A PP1-binding motif present in BRCA1 plays a role in its DNA repair function

    PubMed Central

    Yu, Young-Mi; Pace, Serena M.; Allen, Susan R.; Deng, Chu-Xia; Hsu, Lih-Ching

    2008-01-01

    Protein phosphatase 1α (PP1α) regulates phosphorylation of BRCA1, which contains a PP1-binding motif 898KVTF901. Mutation of this motif greatly reduces the interaction between BRCA1 and PP1α. Here we show that mutation of the PP1-binding motif abolishes the ability of BRCA1 to enhance survival of Brca1-deficient mouse mammary tumor cells after DNA damage. The Rad51 focus formation and comet assays revealed that the DNA repair function of BRCA1 was impaired when the PP1-binding motif was mutated. Analysis of subnuclear localization of GFP-tagged BRCA1 demonstrated that mutation of the PP1-binding motif affected BRCA1 redistribution in response to DNA damage. BRCA1 is required for the formation of Rad51 subnuclear foci after DNA damage. Mutation of the PP1-binding motif in BRCA1 also affected recruitment of Rad51 to sites of DNA damage. Consistent with these findings, knockdown of PP1α in BRCA1-proficient cells by small interfering RNA also significantly reduced Rad51 focus formation induced by DNA damage. Further analysis indicated that mutation of the PP1-binding motif compromised BRCA1 activities in homologous recombination. Altogether, our data implicate that interaction with PP1α is important for BRCA1 function in DNA repair. PMID:18953404

  11. Genetic evaluation of BRCA1-A complex genes with triple-negative breast cancer susceptibility in Chinese women

    PubMed Central

    Zheng, Yi-Zi; Qiao, Feng; Yao, Ling; Cao, Zhi-Gang; Ye, Fu-Gui; Wu, Jiong; Hu, Xin; Wang, Bin; Shao, Zhi-Ming

    2016-01-01

    Background The tumor suppressor BRCA1 plays a pivotal role in maintaining genomic stability and tumor suppression. The BRCA1-A complex is required for recruitment of BRCA1 to DNA damage sites, DNA repair and cell cycle checkpoint control. Since germline mutations of BRCA1 often lead to breast tumors that are triple-negative breast cancer (TNBC) type, we aimed to investigate whether genetic deficiency in genes of the BRCA1-A complex is associated with risk to TNBC development. Results We found that rs7250266 in the promoter region of NBA1 confers a decreased risk to TNBC development, but not to non-TNBC susceptibility. In addition, the haplotypes containing two polymorphisms rs7250266 and rs2278256 are associated with a lower chance of TNBC development specifically. Our studies also showed that the protective alleles of rs7250266 (C > G) and rs2278256 (T > C) down-regulate promoter activity of NBA1 in mammary epithelial cells. Methods We investigated associations between the BRCA1-A complex genes and TNBC developing risk in first case-control study of Chinese Han Women population including 414 patients with TNBC and 354 cancer-free controls. We detected 37 common variants in ABRAXAS, RAP80, BRE, BRCC36 and NBA1/MERIT40 genes encoding the BRCA1-A complex and evaluated their genetic susceptibility to the risk of TNBC. An additional cohort with 652 other types of breast cancer (non-TNBC) cases and 890 controls was used to investigate the associations between TNBC-specific SNPs genotype and non-TNBCs susceptibility. Conclusions Genetic variants in NBA1 may be an important genetic determinant of TNBC susceptibility. Further investigation and validation of these SNPs in larger cohorts may facilitate in predication and prevention of TNBC and in counseling individuals for risk of TNBC development. PMID:26848770

  12. DNA repair factor BRCA1 depletion occurs in Alzheimer brains and impairs cognitive function in mice

    PubMed Central

    Suberbielle, Elsa; Djukic, Biljana; Evans, Mark; Kim, Daniel H.; Taneja, Praveen; Wang, Xin; Finucane, Mariel; Knox, Joseph; Ho, Kaitlyn; Devidze, Nino; Masliah, Eliezer; Mucke, Lennart

    2015-01-01

    Maintaining DNA integrity is vital for all cells and organisms. Defective DNA repair may contribute to neurological disorders, including Alzheimer's disease (AD). We found reduced levels of BRCA1, but not of other DNA repair factors, in the brains of AD patients and human amyloid precursor protein (hAPP) transgenic mice. Amyloid-β oligomers reduced BRCA1 levels in primary neuronal cultures. In wild-type mice, knocking down neuronal BRCA1 in the dentate gyrus caused increased DNA double-strand breaks, neuronal shrinkage, synaptic plasticity impairments, and learning and memory deficits, but not apoptosis. Low levels of hAPP/Amyloid-β overexpression exacerbated these effects. Physiological neuronal activation increased BRCA1 levels, whereas stimulating predominantly extrasynaptic N-methyl-D-aspartate receptors promoted the proteasomal degradation of BRCA1. We conclude that BRCA1 is regulated by neuronal activity, protects the neuronal genome, and critically supports neuronal integrity and cognitive functions. Pathological accumulation of Aβ depletes neuronal BRCA1, which may contribute to cognitive deficits in AD. PMID:26615780

  13. Gene expression profiling integrated into network modelling reveals heterogeneity in the mechanisms of BRCA1 tumorigenesis

    PubMed Central

    Fernández-Ramires, R; Solé, X; De Cecco, L; Llort, G; Cazorla, A; Bonifaci, N; Garcia, M J; Caldés, T; Blanco, I; Gariboldi, M; Pierotti, M A; Pujana, M A; Benítez, J; Osorio, A

    2009-01-01

    Background: Gene expression profiling has distinguished sporadic breast tumour classes with genetic and clinical differences. Less is known about the molecular classification of familial breast tumours, which are generally considered to be less heterogeneous. Here, we describe molecular signatures that define BRCA1 subclasses depending on the expression of the gene encoding for oestrogen receptor, ESR1. Methods: For this purpose, we have used the Oncochip v2, a cancer-related cDNA microarray to analyze 14 BRCA1-associated breast tumours. Results: Signatures were found to be molecularly associated with different biological processes and transcriptional regulatory programs. The signature of ESR1-positive tumours was mainly linked to cell proliferation and regulated by ER, whereas the signature of ESR1-negative tumours was mainly linked to the immune response and possibly regulated by transcription factors of the REL/NFκB family. These signatures were then verified in an independent series of familial and sporadic breast tumours, which revealed a possible prognostic value for each subclass. Over-expression of immune response genes seems to be a common feature of ER-negative sporadic and familial breast cancer and may be associated with good prognosis. Interestingly, the ESR1-negative tumours were substratified into two groups presenting slight differences in the magnitude of the expression of immune response transcripts and REL/NFκB transcription factors, which could be dependent on the type of BRCA1 germline mutation. Conclusion: This study reveals the molecular complexity of BRCA1 breast tumours, which are found to display similarities to sporadic tumours, and suggests possible prognostic implications. PMID:19826428

  14. Direct visualization of the highly polymorphic RNU2 locus in proximity to the BRCA1 gene.

    PubMed

    Tessereau, Chloé; Buisson, Monique; Monnet, Nastasia; Imbert, Marine; Barjhoux, Laure; Schluth-Bolard, Caroline; Sanlaville, Damien; Conseiller, Emmanuel; Ceppi, Maurizio; Sinilnikova, Olga M; Mazoyer, Sylvie

    2013-01-01

    Although the breast cancer susceptibility gene BRCA1 is one of the most extensively characterized genetic loci, much less is known about its upstream variable number tandem repeat element, the RNU2 locus. RNU2 encodes the U2 small nuclear RNA, an essential splicing element, but this locus is missing from the human genome assembly due to the inherent difficulty in the assembly of repetitive sequences. To fill the gap between RNU2 and BRCA1, we have reconstructed the physical map of this region by re-examining genomic clone sequences of public databases, which allowed us to precisely localize the RNU2 array 124 kb telomeric to BRCA1. We measured by performing FISH analyses on combed DNA for the first time the exact number of repeats carried by each of the two alleles in 41 individuals and found a range of 6-82 copies and a level of heterozygosity of 98%. The precise localisation of the RNU2 locus in the genome reference assembly and the implementation of a new technical tool to study it will make the detailed exploration of this locus possible. This recently neglected macrosatellite could be valuable for evaluating the potential role of structural variations in disease due to its location next to a major cancer susceptibility gene. PMID:24146815

  15. BRCA1 positively regulates FOXO3 expression by restricting FOXO3 gene methylation and epigenetic silencing through targeting EZH2 in breast cancer

    PubMed Central

    Gong, C; Yao, S; Gomes, A R; Man, E P S; Lee, H J; Gong, G; Chang, S; Kim, S-B; Fujino, K; Kim, S-W; Park, S K; Lee, J W; Lee, M H; Khoo, U S; Lam, E W-F

    2016-01-01

    BRCA1 mutation or depletion correlates with basal-like phenotype and poor prognosis in breast cancer but the underlying reason remains elusive. RNA and protein analysis of a panel of breast cancer cell lines revealed that BRCA1 deficiency is associated with downregulation of the expression of the pleiotropic tumour suppressor FOXO3. Knockdown of BRCA1 by small interfering RNA (siRNA) resulted in downregulation of FOXO3 expression in the BRCA1-competent MCF-7, whereas expression of BRCA1 restored FOXO3 expression in BRCA1-defective HCC70 and MDA-MB-468 cells, suggesting a role of BRCA1 in the control of FOXO3 expression. Treatment of HCC70 and MDA-MB-468 cells with either the DNA methylation inhibitor 5-aza-2'-deoxycitydine, the N-methyltransferase enhancer of zeste homologue 2 (EZH2) inhibitor GSK126 or EZH2 siRNA induced FOXO3 mRNA and protein expression, but had no effect on the BRCA1-competent MCF-7 cells. Chromatin immunoprecipitation (ChIP) analysis demonstrated that BRCA1, EZH2, DNMT1/3a/b and histone H3 lysine 27 trimethylation (H3K27me3) are recruited to the endogenous FOXO3 promoter, further advocating that these proteins interact to modulate FOXO3 methylation and expression. In addition, ChIP results also revealed that BRCA1 depletion promoted the recruitment of the DNA methyltransferases DNMT1/3a/3b and the enrichment of the EZH2-mediated transcriptional repressive epigenetic marks H3K27me3 on the FOXO3 promoter. Methylated DNA immunoprecipitation assays also confirmed increased CpG methylation of the FOXO3 gene on BRCA1 depletion. Analysis of the global gene methylation profiles of a cohort of 33 familial breast tumours revealed that FOXO3 promoter methylation is significantly associated with BRCA1 mutation. Furthermore, immunohistochemistry further suggested that FOXO3 expression was significantly associated with BRCA1 status in EZH2-positive breast cancer. Consistently, high FOXO3 and EZH2 mRNA levels were significantly associated with good and poor

  16. Scientists find a new function for breast cancer gene BRCA1

    Cancer.gov

    Scientists at the National Cancer Institute (NCI) have uncovered a new function for BRCA1, a gene most commonly associated with hereditary breast and ovarian cancer. Working on mouse cells in the lab, they discovered that BRCA1 suppresses the expression o

  17. BRCA1 functions independently of homologous recombination in DNA interstrand cross-link repair

    PubMed Central

    Bunting, Samuel F; Callen, Elsa; Kozak, Marina L; Kim, Jung-Min; Wong, Nancy; Lopez-Contreras, Andres J; Ludwig, Thomas; Baer, Richard; Faryabi, Robert B; Malhowski, Amy; Chen, Hua-Tang; Fernandez-Capetillo, Oscar; D’Andrea, Alan; Nussenzweig, Andre

    2012-01-01

    Brca1 is required for DNA repair by homologous recombination (HR) and normal embryonic development. Here we report that deletion of the DNA damage response factor 53BP1 overcomes embryonic lethality in Brca1-nullizygous mice, and rescues HR deficiency, as measured by hypersensitivity to PARP (polyADP-ribose polymerase) inhibition. However, Brca1,53BP1 double-deficient cells are hypersensitive to DNA interstrand cross-links (ICLs), indicating that BRCA1 has an additional role in DNA cross-link repair that is distinct from HR. Disruption of the non-homologous end-joining (NHEJ) factor, Ku, promotes DNA repair in Brca1-deficient cells; however deletion of either Ku or 53BP1 exacerbates genomic instability in cells lacking FANCD2, a mediator of the Fanconi Anemia pathway for ICL repair. BRCA1 therefore has two separate roles in ICL repair, whereas FANCD2 provides a key activity that can not be bypassed by ablation of 53BP1 or Ku. PMID:22445484

  18. DNA Binding Region” of BRCA1 Affects Genetic Stability through modulating the Intra-S-Phase Checkpoint

    PubMed Central

    Masuda, Takaaki; Xu, Xiaoling; Dimitriadis, Emilios K.; Lahusen, Tyler; Deng, Chu-Xia

    2016-01-01

    The breast cancer associated gene 1 (BRCA1) contains 3 domains: an N-terminal RING domain with ubiquitin E3 ligase activity, C-terminal BRCT protein interaction domain and a central region. RING and BRCT domains are well characterized, yet the function of the central region remains unclear. In this study, we identified an essential DNA binding region (DBR: 421-701 amino acids) within the central region of human BRCA1, and found that BRCA1 brings DNA together and preferably binds to splayed-arm DNA in a sequence-independent manner. To investigate the biological role of the DBR, we generated mouse ES cells, which lack the DBR (ΔDBR) by using the TALEN method. The ΔDBR cells exhibited decreased survival as compared to the wild type (WT) cells treated with a PARP inhibitor, however they have an intact ability to conduct DNA repair mediated by homologous recombination (HR). The ΔDBR cells continued to incorporate more EdU in the presence of hydroxyurea (HU), which causes replication stress and exhibited reduced viability than the WT cells. Moreover, phosphorylation of CHK1, which regulates the intra-S phase checkpoint, was moderately decreased in ΔDBR cells. These data suggest that DNA binding by BRCA1 affects the stability of DNA replication folks, resulting in weakened intra-S-phase checkpoint control in the ΔDBR cells. The ΔDBR cells also exhibited an increased number of abnormal chromosome structures as compared with WT cells, indicating that the ΔDBR cells have increased genetic instability. Thus, we demonstrated that the DBR of BRCA1 modulates genetic stability through the intra-S-phase checkpoint activated by replication stress. PMID:26884712

  19. Roles of DNA mutation in the coding region and DNA methylation in the 5' flanking region of BRCA1 in canine mammary tumors.

    PubMed

    Qiu, Hengbin; Lin, Deigui

    2016-07-01

    The Breast cancer 1, early onset gene (BRCA1) is known to be significantly associated with human familial breast cancer and is identified to play an important role in canine mammary tumors. Here, genetic variations in the coding region and DNA methylation in the 5' flanking region of BRCA1 in canine mammary tumor samples, 15 each of benign and malignant against 10 normal canine mammary tissue samples, were analyzed using the direct sequencing method. The results indicated two point mutations each in the coding region of canine BRCA1 in one benign mammary tumor sample (4702G >T and 4765G >T) and in one malignant canine mammary tumor sample (3619A >G and 4006G >A). No mutations were detected in the normal canine mammary tissue samples. The 4702G >T mutation was found to terminate further translation. The physical effect of the 4765G >T mutation was found to be the repalacement of the glutamate residue with glutamine. The physical effect of the 3619A >G mutation was found to be the replacement of the threonine residue with alanine, and that of mutation 4006G >A was the replacement of the valine residue with isoleucine in the BRCA1 protein. Bisulfite sequencing detected methylated CpG sites in one canine malignant mammary tumor sample. In conclusion, the present study elucidated the mutational status of the BRCA1 coding region and methylation status of the 5' flanking region of BRCA1 in canine mammary tumors. PMID:26888582

  20. Roles of DNA mutation in the coding region and DNA methylation in the 5′ flanking region of BRCA1 in canine mammary tumors

    PubMed Central

    QIU, Hengbin; LIN, Deigui

    2016-01-01

    The Breast cancer 1, early onset gene (BRCA1) is known to be significantly associated with human familial breast cancer and is identified to play an important role in canine mammary tumors. Here, genetic variations in the coding region and DNA methylation in the 5′ flanking region of BRCA1 in canine mammary tumor samples, 15 each of benign and malignant against 10 normal canine mammary tissue samples, were analyzed using the direct sequencing method. The results indicated two point mutations each in the coding region of canine BRCA1 in one benign mammary tumor sample (4702G >T and 4765G >T) and in one malignant canine mammary tumor sample (3619A >G and 4006G >A). No mutations were detected in the normal canine mammary tissue samples. The 4702G >T mutation was found to terminate further translation. The physical effect of the 4765G >T mutation was found to be the repalacement of the glutamate residue with glutamine. The physical effect of the 3619A >G mutation was found to be the replacement of the threonine residue with alanine, and that of mutation 4006G >A was the replacement of the valine residue with isoleucine in the BRCA1 protein. Bisulfite sequencing detected methylated CpG sites in one canine malignant mammary tumor sample. In conclusion, the present study elucidated the mutational status of the BRCA1 coding region and methylation status of the 5′ flanking region of BRCA1 in canine mammary tumors. PMID:26888582

  1. BRCA1 — EDRN Public Portal

    Cancer.gov

    BRCA1 is a nuclear phosphoprotein that functions as a tumor suppressor. BRCA1 combines with other tumor suppressors, DNA damage sensors, and signal transducers to form a large multi-subunit protein complex known as the BRCA1-associated genome surveillance complex (BASC). BRCA1 associates with RNA polymerase II, and through the C-terminal domain, also interacts with histone deacetylase complexes. This protein thus plays a role in transcription, DNA repair of double-stranded breaks, and recombination. Mutations in this gene are responsible for approximately 40% of inherited breast cancers and more than 80% of inherited breast and ovarian cancers.

  2. A phase I trial of retroviral BRCA1sv gene therapy in ovarian cancer.

    PubMed

    Tait, D L; Obermiller, P S; Redlin-Frazier, S; Jensen, R A; Welcsh, P; Dann, J; King, M C; Johnson, D H; Holt, J T

    1997-11-01

    Gene transfer of BRCA1sv (a normal splice variant of BRCA1) into ovarian cancer cells produces growth inhibition in vitro and tumor suppression in nude mouse xenografts. As an initial step toward gene replacement therapy for ovarian cancer, we conducted a Phase I trial to assess the pharmacokinetics and toxicity of i.p. BRCA1sv retroviral vector therapy. Following placement of an indwelling Port-a-Cath in patients, a dose escalation study was performed of four daily i.p. infusions spanning doses from 3 to 300 ml (i.e., 10(10) viral particles) at half-log intervals (23 cycles in 12 patients). Gene transfer and expression were documented by PCR, Southern blot, reverse transcription-PCR, and nuclease protection assays. Pharmacokinetics were assessed by PCR and Southern blots detecting vector DNA, and toxicity was evaluated by clinical exam and fluid analysis. Three of 12 patients developed an acute sterile peritonitis, which spontaneously resolved within 48 h. Plasma and peritoneal antibodies to the retroviral envelope protein were detected only in patients treated with the highest dose levels but not in others, despite repeat dosing for an interval of up to 4 months. Eight patients showed stable disease for 4-16 weeks, and three patients showed tumor reduction with diminished miliary tumor implants at reoperation (two patients) and radiographic shrinkage of measurable disease (one patient). The vector-related complication of peritonitis was observed in three patients but resolved quickly as in preclinical mouse studies. Ovarian cancer may provide an important model for retroviral gene therapy studies due to vector stability, minimal antibody response, and access to tumor by i.p. therapy. PMID:9815585

  3. A strong candidate for the breast and ovarian cancer susceptibility gene BRCA1

    SciTech Connect

    Miki, Y.; Swenson, J.; Yakumo, K.; Lewis, C.; Neuhausen, S.; Goldgar, D.; Shattuck-Eidens, D.; Harshman, K.; Tavtigian, S.; Liu, Q.

    1994-10-07

    A strong candidate for the 17q-linked BRCA1 gene, which influences susceptibility to breast and ovarian cancer, has been identified by positional cloning methods. Probable predisposing mutations have been detected in five of eight kindreds presumed to segregate BRCA1 susceptibility alleles. The mutations include an 11-base pair deletion, a 1-base pair insertion, a stop codon, a missense substitution, and an inferred regulatory mutation. The BRCA1 gene is expressed in numerous tissues, including breast and ovary, and encodes a predicted protein of 1863 amino acids. This protein contains a zinc finger domain in its amino-terminal region, but is otherwise unrelated to previously described proteins. Identification of BRCA1 should facilitate early diagnosis of breast and ovarian cancer susceptibility in some individuals as well as a better understanding of breast cancer biology.

  4. Evaluation of the XRCC1 gene as a phenotypic modifier in BRCA1/2 mutation carriers. Results from the consortium of investigators of modifiers of BRCA1/BRCA2

    PubMed Central

    Osorio, A; Milne, R L; Alonso, R; Pita, G; Peterlongo, P; Teulé, A; Nathanson, K L; Domchek, S M; Rebbeck, T; Lasa, A; Konstantopoulou, I; Hogervorst, F B; Verhoef, S; van Dooren, M F; Jager, A; Ausems, M G E M; Aalfs, C M; van Asperen, C J; Vreeswijk, M; Waisfisz, Q; Van Roozendaal, C E; Ligtenberg, M J; Easton, D F; Peock, S; Cook, M; Oliver, C T; Frost, D; Curzon, B; Evans, D G; Lalloo, F; Eeles, R; Izatt, L; Davidson, R; Adlard, J; Eccles, D; Ong, K-r; Douglas, F; Downing, S; Brewer, C; Walker, L; Nevanlinna, H; Aittomäki, K; Couch, F J; Fredericksen, Z; Lindor, N M; Godwin, A; Isaacs, C; Caligo, M A; Loman, N; Jernström, H; Barbany-Bustinza, G; Liljegren, A; Ehrencrona, H; Stenmark-Askmalm, M; Feliubadaló, L; Manoukian, S; Peissel, B; Zaffaroni, D; Bonanni, B; Fortuzzi, S; Johannsson, O T; Chenevix-Trench, G; Chen, X-C; Beesley, J; Spurdle, A B; Sinilnikova, O M; Healey, S; McGuffog, L; Antoniou, A C; Brunet, J; Radice, P; Benítez, J

    2011-01-01

    Background: Single-nucleotide polymorphisms (SNPs) in genes involved in DNA repair are good candidates to be tested as phenotypic modifiers for carriers of mutations in the high-risk susceptibility genes BRCA1 and BRCA2. The base excision repair (BER) pathway could be particularly interesting given the relation of synthetic lethality that exists between one of the components of the pathway, PARP1, and both BRCA1 and BRCA2. In this study, we have evaluated the XRCC1 gene that participates in the BER pathway, as phenotypic modifier of BRCA1 and BRCA2. Methods: Three common SNPs in the gene, c.-77C>T (rs3213245) p.Arg280His (rs25489) and p.Gln399Arg (rs25487) were analysed in a series of 701 BRCA1 and 576 BRCA2 mutation carriers. Results: An association was observed between p.Arg280His-rs25489 and breast cancer risk for BRCA2 mutation carriers, with rare homozygotes at increased risk relative to common homozygotes (hazard ratio: 22.3, 95% confidence interval: 14.3–34, P<0.001). This association was further tested in a second series of 4480 BRCA1 and 3016 BRCA2 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1 and BRCA2. Conclusions and inte No evidence of association was found when the larger series was analysed which lead us to conclude that none of the three SNPs are significant modifiers of breast cancer risk for mutation carriers. PMID:21427728

  5. BRCA1 Haploinsufficiency Leads to Altered Expression of Genes Involved in Cellular Proliferation and Development

    PubMed Central

    Feilotter, Harriet E.; Michel, Claire; Uy, Paolo; Bathurst, Lauren; Davey, Scott

    2014-01-01

    The assessment of BRCA1 and BRCA2 coding sequences to identify pathogenic mutations associated with inherited breast/ovarian cancer syndrome has provided a method to identify high-risk individuals, allowing them to seek preventative treatments and strategies. However, the current test is expensive, and cannot differentiate between pathogenic variants and those that may be benign. Focusing only on one of the two BRCA partners, we have developed a biological assay for haploinsufficiency of BRCA1. Using a series of EBV-transformed cell lines, we explored gene expression patterns in cells that were BRCA1 wildtype compared to those that carried (heterozygous) BRCA1 pathogenic mutations. We identified a subset of 43 genes whose combined expression pattern is a sensitive predictor of BRCA1 status. The gene set was disproportionately made up of genes involved in cellular differentiation, lending credence to the hypothesis that single copy loss of BRCA1 function may impact differentiation, rendering cells more susceptible to undergoing malignant processes. PMID:24950059

  6. Nucleolar exit of RNF8 and BRCA1 in response to DNA damage

    SciTech Connect

    Guerra-Rebollo, Marta; Mateo, Francesca; Franke, Kristin; Huen, Michael S.Y.; Lopitz-Otsoa, Fernando; Rodriguez, Manuel S.; Plans, Vanessa; Thomson, Timothy M.

    2012-11-01

    The induction of DNA double-strand breaks (DSBs) elicits a plethora of responses that redirect many cellular functions to the vital task of repairing the injury, collectively known as the DNA damage response (DDR). We have found that, in the absence of DNA damage, the DSB repair factors RNF8 and BRCA1 are associated with the nucleolus. Shortly after exposure of cells to {gamma}-radiation, RNF8 and BRCA1 translocated from the nucleolus to damage foci, a traffic that was reverted several hours after the damage. RNF8 interacted through its FHA domain with the ribosomal protein RPSA, and knockdown of RPSA caused a depletion of nucleolar RNF8 and BRCA1, suggesting that the interaction of RNF8 with RPSA is critical for the nucleolar localization of these DDR factors. Knockdown of RPSA or RNF8 impaired bulk protein translation, as did {gamma}-irradiation, the latter being partially countered by overexpression of exogenous RNF8. Our results suggest that RNF8 and BRCA1 are anchored to the nucleolus through reversible interactions with RPSA and that, in addition to its known functions in DDR, RNF8 may play a role in protein synthesis, possibly linking the nucleolar exit of this factor to the attenuation of protein synthesis in response to DNA damage. -- Highlights: Black-Right-Pointing-Pointer RNF8 and BRCA1 are associated with the nucleolus of undamaged cells. Black-Right-Pointing-Pointer Upon {gamma}-radiation, RNF8 and BRCA1 are translocated from the nucleolus to damage foci. Black-Right-Pointing-Pointer The ribosomal protein RPSA anchors RNF8 to the nucleolus. Black-Right-Pointing-Pointer RNF8 may play previously unsuspected roles in protein synthesis.

  7. Role of BRCA1 and BRCA2 gene mutations in epithelial ovarian cancer in Indian population: a pilot study

    PubMed Central

    Sharma, Shikha; Rajaram, Shalini; Sharma, Tusha; Goel, Neerja; Agarwal, Sarla; Banerjee, Basu Dev

    2014-01-01

    Ovarian cancer is a silent killer as most patients have non-specific symptoms and usually present in advanced stage of the disease. It occurs due to certain genetic alterations and mutations namely founder mutations, 187delAG and 5385insC in BRCA1 and 6174delT in BRCA2 which are associated with specific family histories. These highly penetrant susceptibility genes responsible for approximately half of families containing 2 or more ovarian cancer cases account for less than 40% of the familial excess malignancy risk. The remaining risk may be due to single nucleotide polymorphisms (SNPs) which are single base change in a DNA sequence with usual alternatives of two possible nucleotides at a given position. Preliminary study involving 30 women with histologically proven epithelial ovarian cancer was conducted and their detailed genetic analysis was carried out. Regions of founder mutations on BRCA1 and BRCA2 were amplified and sequenced using primers designed based on 200 bp upstream and downstream regions of the mutation sites. Five sequence variants in BRCA1 were identified of which three novel sequence variants were found in 23 patients while in BRCA2, one novel sequence variant was found. The three founder mutations 187delAG, 5385insC in BRCA1 and 6174delT in BRCA2 were not seen in any of the subjects. PMID:24955283

  8. Genetic Variation of the Brca1 and Brca2 Genes in Macedonian Patients

    PubMed Central

    Maleva, I; Madjunkova, S; Bozhinovski, G; Smickova, E; Kondov, G; Spiroski, Z; Arsovski, A; Plaseska-Karanfilska, D

    2012-01-01

    The most significant and well characterized genetic risk factors for breast and/or ovarian cancer are germline mutations in the BRCA1 and BRCA2 genes. The BRCA1 and BRCA2 gene mutations strikingly increase breast cancer risk, suggesting that polymorphisms in these genes are logical candidates in seeking to identify low penetrance susceptibility alleles. The aim of this study was to initiate a screen for BRCA1/2 gene mutations in order to identify the genetic variants in the Republic of Macedonia, and to evaluate the association of several single nucleotide polymorphisms (SNPs) in these genes with breast cancer risk. In this study, we included 100 patients with invasive breast cancer from the Republic of Macedonia, classified according to their family history and 100 controls. The methodology included direct sequencing, single nucleotide primer extension method and multiplex ligation probe amplification (MLPA) analysis, all followed by capillary electrophoresis (CE) on an ABI PRISM™ 3130 Genetic Analyzer. We identified a total of seven carriers of mutations in the BRCA1/2 genes. None of the tested polymorphisms was associated with sporadic breast cancer risk, however, polymorphism rs8176267 in BRCA1 and N372H in BRCA2 showed an association with breast cancer risk in patients with at least one family member with breast cancer. PMID:24052750

  9. MRN, CtIP, and BRCA1 mediate repair of topoisomerase II–DNA adducts

    PubMed Central

    Aparicio, Tomas; Baer, Richard; Gottesman, Max

    2016-01-01

    Repair of DNA double-strand breaks (DSBs) with complex ends poses a special challenge, as additional processing is required before DNA ligation. For example, protein–DNA adducts must be removed to allow repair by either nonhomologous end joining or homology-directed repair. Here, we investigated the processing of topoisomerase II (Top2)–DNA adducts induced by treatment with the chemotherapeutic agent etoposide. Through biochemical analysis in Xenopus laevis egg extracts, we establish that the MRN (Mre11, Rad50, and Nbs1) complex, CtIP, and BRCA1 are required for both the removal of Top2–DNA adducts and the subsequent resection of Top2-adducted DSB ends. Moreover, the interaction between CtIP and BRCA1, although dispensable for resection of endonuclease-generated DSB ends, is required for resection of Top2-adducted DSBs, as well as for cellular resistance to etoposide during genomic DNA replication. PMID:26880199

  10. DNA glycosylases involved in base excision repair may be associated with cancer risk in BRCA1 and BRCA2 mutation carriers.

    PubMed

    Osorio, Ana; Milne, Roger L; Kuchenbaecker, Karoline; Vaclová, Tereza; Pita, Guillermo; Alonso, Rosario; Peterlongo, Paolo; Blanco, Ignacio; de la Hoya, Miguel; Duran, Mercedes; Díez, Orland; Ramón Y Cajal, Teresa; Konstantopoulou, Irene; Martínez-Bouzas, Cristina; Andrés Conejero, Raquel; Soucy, Penny; McGuffog, Lesley; Barrowdale, Daniel; Lee, Andrew; Swe-Brca; Arver, Brita; Rantala, Johanna; Loman, Niklas; Ehrencrona, Hans; Olopade, Olufunmilayo I; Beattie, Mary S; Domchek, Susan M; Nathanson, Katherine; Rebbeck, Timothy R; Arun, Banu K; Karlan, Beth Y; Walsh, Christine; Lester, Jenny; John, Esther M; Whittemore, Alice S; Daly, Mary B; Southey, Melissa; Hopper, John; Terry, Mary B; Buys, Saundra S; Janavicius, Ramunas; Dorfling, Cecilia M; van Rensburg, Elizabeth J; Steele, Linda; Neuhausen, Susan L; Ding, Yuan Chun; Hansen, Thomas V O; Jønson, Lars; Ejlertsen, Bent; Gerdes, Anne-Marie; Infante, Mar; Herráez, Belén; Moreno, Leticia Thais; Weitzel, Jeffrey N; Herzog, Josef; Weeman, Kisa; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Scuvera, Giulietta; Bonanni, Bernardo; Mariette, Frederique; Volorio, Sara; Viel, Alessandra; Varesco, Liliana; Papi, Laura; Ottini, Laura; Tibiletti, Maria Grazia; Radice, Paolo; Yannoukakos, Drakoulis; Garber, Judy; Ellis, Steve; Frost, Debra; Platte, Radka; Fineberg, Elena; Evans, Gareth; Lalloo, Fiona; Izatt, Louise; Eeles, Ros; Adlard, Julian; Davidson, Rosemarie; Cole, Trevor; Eccles, Diana; Cook, Jackie; Hodgson, Shirley; Brewer, Carole; Tischkowitz, Marc; Douglas, Fiona; Porteous, Mary; Side, Lucy; Walker, Lisa; Morrison, Patrick; Donaldson, Alan; Kennedy, John; Foo, Claire; Godwin, Andrew K; Schmutzler, Rita Katharina; Wappenschmidt, Barbara; Rhiem, Kerstin; Engel, Christoph; Meindl, Alfons; Ditsch, Nina; Arnold, Norbert; Plendl, Hans Jörg; Niederacher, Dieter; Sutter, Christian; Wang-Gohrke, Shan; Steinemann, Doris; Preisler-Adams, Sabine; Kast, Karin; Varon-Mateeva, Raymonda; Gehrig, Andrea; Stoppa-Lyonnet, Dominique; Sinilnikova, Olga M; Mazoyer, Sylvie; Damiola, Francesca; Poppe, Bruce; Claes, Kathleen; Piedmonte, Marion; Tucker, Kathy; Backes, Floor; Rodríguez, Gustavo; Brewster, Wendy; Wakeley, Katie; Rutherford, Thomas; Caldés, Trinidad; Nevanlinna, Heli; Aittomäki, Kristiina; Rookus, Matti A; van Os, Theo A M; van der Kolk, Lizet; de Lange, J L; Meijers-Heijboer, Hanne E J; van der Hout, A H; van Asperen, Christi J; Gómez Garcia, Encarna B; Hoogerbrugge, Nicoline; Collée, J Margriet; van Deurzen, Carolien H M; van der Luijt, Rob B; Devilee, Peter; Hebon; Olah, Edith; Lázaro, Conxi; Teulé, Alex; Menéndez, Mireia; Jakubowska, Anna; Cybulski, Cezary; Gronwald, Jacek; Lubinski, Jan; Durda, Katarzyna; Jaworska-Bieniek, Katarzyna; Johannsson, Oskar Th; Maugard, Christine; Montagna, Marco; Tognazzo, Silvia; Teixeira, Manuel R; Healey, Sue; Investigators, Kconfab; Olswold, Curtis; Guidugli, Lucia; Lindor, Noralane; Slager, Susan; Szabo, Csilla I; Vijai, Joseph; Robson, Mark; Kauff, Noah; Zhang, Liying; Rau-Murthy, Rohini; Fink-Retter, Anneliese; Singer, Christian F; Rappaport, Christine; Geschwantler Kaulich, Daphne; Pfeiler, Georg; Tea, Muy-Kheng; Berger, Andreas; Phelan, Catherine M; Greene, Mark H; Mai, Phuong L; Lejbkowicz, Flavio; Andrulis, Irene; Mulligan, Anna Marie; Glendon, Gord; Toland, Amanda Ewart; Bojesen, Anders; Pedersen, Inge Sokilde; Sunde, Lone; Thomassen, Mads; Kruse, Torben A; Jensen, Uffe Birk; Friedman, Eitan; Laitman, Yael; Shimon, Shani Paluch; Simard, Jacques; Easton, Douglas F; Offit, Kenneth; Couch, Fergus J; Chenevix-Trench, Georgia; Antoniou, Antonis C; Benitez, Javier

    2014-04-01

    Single Nucleotide Polymorphisms (SNPs) in genes involved in the DNA Base Excision Repair (BER) pathway could be associated with cancer risk in carriers of mutations in the high-penetrance susceptibility genes BRCA1 and BRCA2, given the relation of synthetic lethality that exists between one of the components of the BER pathway, PARP1 (poly ADP ribose polymerase), and both BRCA1 and BRCA2. In the present study, we have performed a comprehensive analysis of 18 genes involved in BER using a tagging SNP approach in a large series of BRCA1 and BRCA2 mutation carriers. 144 SNPs were analyzed in a two stage study involving 23,463 carriers from the CIMBA consortium (the Consortium of Investigators of Modifiers of BRCA1 and BRCA2). Eleven SNPs showed evidence of association with breast and/or ovarian cancer at p<0.05 in the combined analysis. Four of the five genes for which strongest evidence of association was observed were DNA glycosylases. The strongest evidence was for rs1466785 in the NEIL2 (endonuclease VIII-like 2) gene (HR: 1.09, 95% CI (1.03-1.16), p = 2.7 × 10(-3)) for association with breast cancer risk in BRCA2 mutation carriers, and rs2304277 in the OGG1 (8-guanine DNA glycosylase) gene, with ovarian cancer risk in BRCA1 mutation carriers (HR: 1.12 95%CI: 1.03-1.21, p = 4.8 × 10(-3)). DNA glycosylases involved in the first steps of the BER pathway may be associated with cancer risk in BRCA1/2 mutation carriers and should be more comprehensively studied. PMID:24698998

  11. DNA Glycosylases Involved in Base Excision Repair May Be Associated with Cancer Risk in BRCA1 and BRCA2 Mutation Carriers

    PubMed Central

    Osorio, Ana; Milne, Roger L.; Kuchenbaecker, Karoline; Vaclová, Tereza; Pita, Guillermo; Alonso, Rosario; Peterlongo, Paolo; Blanco, Ignacio; de la Hoya, Miguel; Duran, Mercedes; Díez, Orland; Ramón y Cajal, Teresa; Konstantopoulou, Irene; Martínez-Bouzas, Cristina; Andrés Conejero, Raquel; Soucy, Penny; McGuffog, Lesley; Barrowdale, Daniel; Lee, Andrew; SWE-BRCA; Arver, Brita; Rantala, Johanna; Loman, Niklas; Ehrencrona, Hans; Olopade, Olufunmilayo I.; Beattie, Mary S.; Domchek, Susan M.; Nathanson, Katherine; Rebbeck, Timothy R.; Arun, Banu K.; Karlan, Beth Y.; Walsh, Christine; Lester, Jenny; John, Esther M.; Whittemore, Alice S.; Daly, Mary B.; Southey, Melissa; Hopper, John; Terry, Mary B.; Buys, Saundra S.; Janavicius, Ramunas; Dorfling, Cecilia M.; van Rensburg, Elizabeth J.; Steele, Linda; Neuhausen, Susan L.; Ding, Yuan Chun; Hansen, Thomas v. O.; Jønson, Lars; Ejlertsen, Bent; Gerdes, Anne-Marie; Infante, Mar; Herráez, Belén; Moreno, Leticia Thais; Weitzel, Jeffrey N.; Herzog, Josef; Weeman, Kisa; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Scuvera, Giulietta; Bonanni, Bernardo; Mariette, Frederique; Volorio, Sara; Viel, Alessandra; Varesco, Liliana; Papi, Laura; Ottini, Laura; Tibiletti, Maria Grazia; Radice, Paolo; Yannoukakos, Drakoulis; Garber, Judy; Ellis, Steve; Frost, Debra; Platte, Radka; Fineberg, Elena; Evans, Gareth; Lalloo, Fiona; Izatt, Louise; Eeles, Ros; Adlard, Julian; Davidson, Rosemarie; Cole, Trevor; Eccles, Diana; Cook, Jackie; Hodgson, Shirley; Brewer, Carole; Tischkowitz, Marc; Douglas, Fiona; Porteous, Mary; Side, Lucy; Walker, Lisa; Morrison, Patrick; Donaldson, Alan; Kennedy, John; Foo, Claire; Godwin, Andrew K.; Schmutzler, Rita Katharina; Wappenschmidt, Barbara; Rhiem, Kerstin; Engel, Christoph; Meindl, Alfons; Ditsch, Nina; Arnold, Norbert; Plendl, Hans Jörg; Niederacher, Dieter; Sutter, Christian; Wang-Gohrke, Shan; Steinemann, Doris; Preisler-Adams, Sabine; Kast, Karin; Varon-Mateeva, Raymonda; Gehrig, Andrea; Stoppa-Lyonnet, Dominique; Sinilnikova, Olga M.; Mazoyer, Sylvie; Damiola, Francesca; Poppe, Bruce; Claes, Kathleen; Piedmonte, Marion; Tucker, Kathy; Backes, Floor; Rodríguez, Gustavo; Brewster, Wendy; Wakeley, Katie; Rutherford, Thomas; Caldés, Trinidad; Nevanlinna, Heli; Aittomäki, Kristiina; Rookus, Matti A.; van Os, Theo A. M.; van der Kolk, Lizet; de Lange, J. L.; Meijers-Heijboer, Hanne E. J.; van der Hout, A. H.; van Asperen, Christi J.; Gómez Garcia, Encarna B.; Hoogerbrugge, Nicoline; Collée, J. Margriet; van Deurzen, Carolien H. M.; van der Luijt, Rob B.; Devilee, Peter; HEBON; Olah, Edith; Lázaro, Conxi; Teulé, Alex; Menéndez, Mireia; Jakubowska, Anna; Cybulski, Cezary; Gronwald, Jacek; Lubinski, Jan; Durda, Katarzyna; Jaworska-Bieniek, Katarzyna; Johannsson, Oskar Th.; Maugard, Christine; Montagna, Marco; Tognazzo, Silvia; Teixeira, Manuel R.; Healey, Sue; Investigators, kConFab; Olswold, Curtis; Guidugli, Lucia; Lindor, Noralane; Slager, Susan; Szabo, Csilla I.; Vijai, Joseph; Robson, Mark; Kauff, Noah; Zhang, Liying; Rau-Murthy, Rohini; Fink-Retter, Anneliese; Singer, Christian F.; Rappaport, Christine; Geschwantler Kaulich, Daphne; Pfeiler, Georg; Tea, Muy-Kheng; Berger, Andreas; Phelan, Catherine M.; Greene, Mark H.; Mai, Phuong L.; Lejbkowicz, Flavio; Andrulis, Irene; Mulligan, Anna Marie; Glendon, Gord; Toland, Amanda Ewart; Bojesen, Anders; Pedersen, Inge Sokilde; Sunde, Lone; Thomassen, Mads; Kruse, Torben A.; Jensen, Uffe Birk; Friedman, Eitan; Laitman, Yael; Shimon, Shani Paluch; Simard, Jacques; Easton, Douglas F.; Offit, Kenneth; Couch, Fergus J.; Chenevix-Trench, Georgia; Antoniou, Antonis C.; Benitez, Javier

    2014-01-01

    Single Nucleotide Polymorphisms (SNPs) in genes involved in the DNA Base Excision Repair (BER) pathway could be associated with cancer risk in carriers of mutations in the high-penetrance susceptibility genes BRCA1 and BRCA2, given the relation of synthetic lethality that exists between one of the components of the BER pathway, PARP1 (poly ADP ribose polymerase), and both BRCA1 and BRCA2. In the present study, we have performed a comprehensive analysis of 18 genes involved in BER using a tagging SNP approach in a large series of BRCA1 and BRCA2 mutation carriers. 144 SNPs were analyzed in a two stage study involving 23,463 carriers from the CIMBA consortium (the Consortium of Investigators of Modifiers of BRCA1 and BRCA2). Eleven SNPs showed evidence of association with breast and/or ovarian cancer at p<0.05 in the combined analysis. Four of the five genes for which strongest evidence of association was observed were DNA glycosylases. The strongest evidence was for rs1466785 in the NEIL2 (endonuclease VIII-like 2) gene (HR: 1.09, 95% CI (1.03–1.16), p = 2.7×10−3) for association with breast cancer risk in BRCA2 mutation carriers, and rs2304277 in the OGG1 (8-guanine DNA glycosylase) gene, with ovarian cancer risk in BRCA1 mutation carriers (HR: 1.12 95%CI: 1.03–1.21, p = 4.8×10−3). DNA glycosylases involved in the first steps of the BER pathway may be associated with cancer risk in BRCA1/2 mutation carriers and should be more comprehensively studied. PMID:24698998

  12. FANCD2 Maintains Fork Stability in BRCA1/2-Deficient Tumors and Promotes Alternative End-Joining DNA Repair.

    PubMed

    Kais, Zeina; Rondinelli, Beatrice; Holmes, Amie; O'Leary, Colin; Kozono, David; D'Andrea, Alan D; Ceccaldi, Raphael

    2016-06-14

    BRCA1/2 proteins function in homologous recombination (HR)-mediated DNA repair and cooperate with Fanconi anemia (FA) proteins to maintain genomic integrity through replication fork stabilization. Loss of BRCA1/2 proteins results in DNA repair deficiency and replicative stress, leading to genomic instability and enhanced sensitivity to DNA-damaging agents. Recent studies have shown that BRCA1/2-deficient tumors upregulate Polθ-mediated alternative end-joining (alt-EJ) repair as a survival mechanism. Whether other mechanisms maintain genomic integrity upon loss of BRCA1/2 proteins is currently unknown. Here we show that BRCA1/2-deficient tumors also upregulate FANCD2 activity. FANCD2 is required for fork protection and fork restart in BRCA1/2-deficient tumors. Moreover, FANCD2 promotes Polθ recruitment at sites of damage and alt-EJ repair. Finally, loss of FANCD2 in BRCA1/2-deficient tumors enhances cell death. These results reveal a synthetic lethal relationship between FANCD2 and BRCA1/2, and they identify FANCD2 as a central player orchestrating DNA repair pathway choice at the replication fork. PMID:27264184

  13. BRCA1: a movement toward cancer prevention

    PubMed Central

    Alli, Elizabeth; Ford, James M

    2015-01-01

    Breast cancer susceptibility gene 1 (BRCA1) was first identified in 1994 and has since been shown to encode a tumor suppressor protein that maintains genetic stability through DNA damage response pathways. Carriers of mutations in BRCA1 are predisposed to breast and ovarian cancer; however, their cancers lack the targets for existing anticancer drugs. We describe a novel chemoprevention approach that uses DNA repair-activating agents to enhance the repair of oxidative DNA damage and, in turn, prevent tumorigenesis in the presence of mutant BRCA1. PMID:27308455

  14. Polo-like kinase 1 mediates BRCA1 phosphorylation and recruitment at DNA double-strand breaks

    PubMed Central

    Chabalier-Taste, Corinne; Canitrot, Yvan; Calsou, Patrick; Larminat, Florence

    2016-01-01

    Accurate repair of DNA double-strand breaks (DSB) caused during DNA replication and by exogenous stresses is critical for the maintenance of genomic integrity. There is growing evidence that the Polo-like kinase 1 (Plk1) that plays a number of pivotal roles in cell proliferation can directly participate in regulation of DSB repair. In this study, we show that Plk1 regulates BRCA1, a key mediator protein required to efficiently repair DSB through homologous recombination (HR). Following induction of DSB, BRCA1 concentrates in distinctive large nuclear foci at damage sites where multiple DNA repair factors accumulate. First, we found that inhibition of Plk1 shortly before DNA damage sensitizes cells to ionizing radiation and reduces DSB repair by HR. Second, we provide evidence that BRCA1 foci formation induced by DSB is reduced when Plk1 is inhibited or depleted. Third, we identified BRCA1 as a novel Plk1 substrate and determined that Ser1164 is the major phosphorylation site for Plk1 in vitro. In cells, mutation of Plk1 sites on BRCA1 significantly delays BRCA1 foci formation following DSB, recapitulating the phenotype observed upon Plk1 inhibition. Our data then assign a key function to Plk1 in BRCA1 foci formation at DSB, emphasizing Plk1 importance in the HR repair of human cells. PMID:26745677

  15. Levels of DNA Methylation Vary at CpG Sites across the BRCA1 Promoter, and Differ According to Triple Negative and “BRCA-Like” Status, in Both Blood and Tumour DNA

    PubMed Central

    Burghel, George J.; Chambers, Philip; Al-Baba, Shadi; Connley, Daniel D.; Brock, Ian W.; Cramp, Helen E.; Dotsenko, Olena; Wilks, Octavia; Wyld, Lynda; Cross, Simon S.; Cox, Angela

    2016-01-01

    Triple negative breast cancer is typically an aggressive and difficult to treat subtype. It is often associated with loss of function of the BRCA1 gene, either through mutation, loss of heterozygosity or methylation. This study aimed to measure methylation of the BRCA1 gene promoter at individual CpG sites in blood, tumour and normal breast tissue, to assess whether levels were correlated between different tissues, and with triple negative receptor status, histopathological scoring for BRCA-like features and BRCA1 protein expression. Blood DNA methylation levels were significantly correlated with tumour methylation at 9 of 11 CpG sites examined (p<0.0007). The levels of tumour DNA methylation were significantly higher in triple negative tumours, and in tumours with high BRCA-like histopathological scores (10 of 11 CpG sites; p<0.01 and p<0.007 respectively). Similar results were observed in blood DNA (6 of 11 CpG sites; p<0.03 and 7 of 11 CpG sites; p<0.02 respectively). This study provides insight into the pattern of CpG methylation across the BRCA1 promoter, and supports previous studies suggesting that tumours with BRCA1 promoter methylation have similar features to those with BRCA1 mutations, and therefore may be suitable for the same targeted therapies. PMID:27463681

  16. Alteration of BRCA1 expression affects alcohol-induced transcription of RNA Pol III-dependent genes

    PubMed Central

    Zhong, Qian; Shi, Ganggang; Zhang, Yanmei; Lu, Lei; Levy, Daniel; Zhong, Shuping

    2014-01-01

    Emerging evidence has indicated that alcohol consumption is an established risk factor for breast cancer. Deregulation of RNA polymerase III (Pol III) transcription enhances cellular Pol III gene production, leading to an increase in translational capacity to promote cell transformation and tumor formation. We have reported that alcohol intake increases Pol III gene transcription to promote cell transformation and tumor formation in vitro and in vivo. Studies revealed that tumor suppressors, pRb, p53, PTEN and Maf1 repress the transcription of Pol III genes. BRCA1 is a tumor suppressor and its mutation is tightly related to breast cancer development. However, it is not clear whether BRCA1 expression affects alcohol-induced transcription of Pol III genes. At the present studies, we report that restoring BRCA1 in HCC 1937 cells, which is a BRCA1 deficient cell line, represses Pol III gene transcription. Expressing mutant or truncated BRCA1 in these cells does not affect the ability of repression on Pol III genes. Our analysis has demonstrated that alcohol induces Pol III gene transcription. More importantly, overexpression of BRCA1 in estrogen receptor positive (ER+) breast cancer cells (MCF-7) decreases the induction of tRNALeu and 5S rRNA genes by alcohol, whereas reduction of BRCA1 by its siRNA slightly increases the transcription of the class of genes. This suggests that BRCA1 is associated with alcohol-induced deregulation of Pol III genes. These studies for the first time demonstrate the role of BRCA1 in induction of Pol III genes by alcohol and uncover a novel mechanism of alcohol-associated breast cancer. PMID:25447904

  17. Common variants of the BRCA1 wild-type allele modify the risk of breast cancer in BRCA1 mutation carriers

    PubMed Central

    Cox, David G.; Simard, Jacques; Sinnett, Daniel; Hamdi, Yosr; Soucy, Penny; Ouimet, Manon; Barjhoux, Laure; Verny-Pierre, Carole; McGuffog, Lesley; Healey, Sue; Szabo, Csilla; Greene, Mark H.; Mai, Phuong L.; Andrulis, Irene L.; Thomassen, Mads; Gerdes, Anne-Marie; Caligo, Maria A.; Friedman, Eitan; Laitman, Yael; Kaufman, Bella; Paluch, Shani S.; Borg, Åke; Karlsson, Per; Stenmark Askmalm, Marie; Barbany Bustinza, Gisela; Nathanson, Katherine L.; Domchek, Susan M.; Rebbeck, Timothy R.; Benítez, Javier; Hamann, Ute; Rookus, Matti A.; van den Ouweland, Ans M.W.; Ausems, Margreet G.E.M.; Aalfs, Cora M.; van Asperen, Christi J.; Devilee, Peter; Gille, Hans J.J.P.; Peock, Susan; Frost, Debra; Evans, D. Gareth; Eeles, Ros; Izatt, Louise; Adlard, Julian; Paterson, Joan; Eason, Jacqueline; Godwin, Andrew K.; Remon, Marie-Alice; Moncoutier, Virginie; Gauthier-Villars, Marion; Lasset, Christine; Giraud, Sophie; Hardouin, Agnès; Berthet, Pascaline; Sobol, Hagay; Eisinger, François; Bressac de Paillerets, Brigitte; Caron, Olivier; Delnatte, Capucine; Goldgar, David; Miron, Alex; Ozcelik, Hilmi; Buys, Saundra; Southey, Melissa C.; Terry, Mary Beth; Singer, Christian F.; Dressler, Anne-Catharina; Tea, Muy-Kheng; Hansen, Thomas V.O.; Johannsson, Oskar; Piedmonte, Marion; Rodriguez, Gustavo C.; Basil, Jack B.; Blank, Stephanie; Toland, Amanda E.; Montagna, Marco; Isaacs, Claudine; Blanco, Ignacio; Gayther, Simon A.; Moysich, Kirsten B.; Schmutzler, Rita K.; Wappenschmidt, Barbara; Engel, Christoph; Meindl, Alfons; Ditsch, Nina; Arnold, Norbert; Niederacher, Dieter; Sutter, Christian; Gadzicki, Dorothea; Fiebig, Britta; Caldes, Trinidad; Laframboise, Rachel; Nevanlinna, Heli; Chen, Xiaoqing; Beesley, Jonathan; Spurdle, Amanda B.; Neuhausen, Susan L.; Ding, Yuan C.; Couch, Fergus J.; Wang, Xianshu; Peterlongo, Paolo; Manoukian, Siranoush; Bernard, Loris; Radice, Paolo; Easton, Douglas F.; Chenevix-Trench, Georgia; Antoniou, Antonis C.; Stoppa-Lyonnet, Dominique; Mazoyer, Sylvie; Sinilnikova, Olga M.

    2011-01-01

    Mutations in the BRCA1 gene substantially increase a woman's lifetime risk of breast cancer. However, there is great variation in this increase in risk with several genetic and non-genetic modifiers identified. The BRCA1 protein plays a central role in DNA repair, a mechanism that is particularly instrumental in safeguarding cells against tumorigenesis. We hypothesized that polymorphisms that alter the expression and/or function of BRCA1 carried on the wild-type (non-mutated) copy of the BRCA1 gene would modify the risk of breast cancer in carriers of BRCA1 mutations. A total of 9874 BRCA1 mutation carriers were available in the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) for haplotype analyses of BRCA1. Women carrying the rare allele of single nucleotide polymorphism rs16942 on the wild-type copy of BRCA1 were at decreased risk of breast cancer (hazard ratio 0.86, 95% confidence interval 0.77–0.95, P = 0.003). Promoter in vitro assays of the major BRCA1 haplotypes showed that common polymorphisms in the regulatory region alter its activity and that this effect may be attributed to the differential binding affinity of nuclear proteins. In conclusion, variants on the wild-type copy of BRCA1 modify risk of breast cancer among carriers of BRCA1 mutations, possibly by altering the efficiency of BRCA1 transcription. PMID:21890493

  18. Common variants of the BRCA1 wild-type allele modify the risk of breast cancer in BRCA1 mutation carriers.

    PubMed

    Cox, David G; Simard, Jacques; Sinnett, Daniel; Hamdi, Yosr; Soucy, Penny; Ouimet, Manon; Barjhoux, Laure; Verny-Pierre, Carole; McGuffog, Lesley; Healey, Sue; Szabo, Csilla; Greene, Mark H; Mai, Phuong L; Andrulis, Irene L; Thomassen, Mads; Gerdes, Anne-Marie; Caligo, Maria A; Friedman, Eitan; Laitman, Yael; Kaufman, Bella; Paluch, Shani S; Borg, Åke; Karlsson, Per; Askmalm, Marie Stenmark; Bustinza, Gisela Barbany; Nathanson, Katherine L; Domchek, Susan M; Rebbeck, Timothy R; Benítez, Javier; Hamann, Ute; Rookus, Matti A; van den Ouweland, Ans M W; Ausems, Margreet G E M; Aalfs, Cora M; van Asperen, Christi J; Devilee, Peter; Gille, Hans J J P; Peock, Susan; Frost, Debra; Evans, D Gareth; Eeles, Ros; Izatt, Louise; Adlard, Julian; Paterson, Joan; Eason, Jacqueline; Godwin, Andrew K; Remon, Marie-Alice; Moncoutier, Virginie; Gauthier-Villars, Marion; Lasset, Christine; Giraud, Sophie; Hardouin, Agnès; Berthet, Pascaline; Sobol, Hagay; Eisinger, François; Bressac de Paillerets, Brigitte; Caron, Olivier; Delnatte, Capucine; Goldgar, David; Miron, Alex; Ozcelik, Hilmi; Buys, Saundra; Southey, Melissa C; Terry, Mary Beth; Singer, Christian F; Dressler, Anne-Catharina; Tea, Muy-Kheng; Hansen, Thomas V O; Johannsson, Oskar; Piedmonte, Marion; Rodriguez, Gustavo C; Basil, Jack B; Blank, Stephanie; Toland, Amanda E; Montagna, Marco; Isaacs, Claudine; Blanco, Ignacio; Gayther, Simon A; Moysich, Kirsten B; Schmutzler, Rita K; Wappenschmidt, Barbara; Engel, Christoph; Meindl, Alfons; Ditsch, Nina; Arnold, Norbert; Niederacher, Dieter; Sutter, Christian; Gadzicki, Dorothea; Fiebig, Britta; Caldes, Trinidad; Laframboise, Rachel; Nevanlinna, Heli; Chen, Xiaoqing; Beesley, Jonathan; Spurdle, Amanda B; Neuhausen, Susan L; Ding, Yuan C; Couch, Fergus J; Wang, Xianshu; Peterlongo, Paolo; Manoukian, Siranoush; Bernard, Loris; Radice, Paolo; Easton, Douglas F; Chenevix-Trench, Georgia; Antoniou, Antonis C; Stoppa-Lyonnet, Dominique; Mazoyer, Sylvie; Sinilnikova, Olga M

    2011-12-01

    Mutations in the BRCA1 gene substantially increase a woman's lifetime risk of breast cancer. However, there is great variation in this increase in risk with several genetic and non-genetic modifiers identified. The BRCA1 protein plays a central role in DNA repair, a mechanism that is particularly instrumental in safeguarding cells against tumorigenesis. We hypothesized that polymorphisms that alter the expression and/or function of BRCA1 carried on the wild-type (non-mutated) copy of the BRCA1 gene would modify the risk of breast cancer in carriers of BRCA1 mutations. A total of 9874 BRCA1 mutation carriers were available in the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) for haplotype analyses of BRCA1. Women carrying the rare allele of single nucleotide polymorphism rs16942 on the wild-type copy of BRCA1 were at decreased risk of breast cancer (hazard ratio 0.86, 95% confidence interval 0.77-0.95, P = 0.003). Promoter in vitro assays of the major BRCA1 haplotypes showed that common polymorphisms in the regulatory region alter its activity and that this effect may be attributed to the differential binding affinity of nuclear proteins. In conclusion, variants on the wild-type copy of BRCA1 modify risk of breast cancer among carriers of BRCA1 mutations, possibly by altering the efficiency of BRCA1 transcription. PMID:21890493

  19. Estimates of the gene frequency of BRCA1 and its contribution to breast and ovarian cancer incidence

    SciTech Connect

    Ford, D.; Easton, D.F.; Peto, J.

    1995-12-01

    The majority of multiple-case families that segregate both breast and ovarian cancer in a dominant fashion are due to mutations in the BRCA1 gene on chromosome 17q. In this paper, we have combined penetrance estimates for BRCA1 with the results of two population-based genetic epidemiological studies to estimate the gene frequency of BRCA1. On the assumption that the excess risk of ovarian cancer in first degree relatives of breast cancer patients and the breast cancer excess in relatives of ovarian cancer patients are both entirely accounted for by BRCA1, we estimate that the BRCA1 gene frequency is 0.0006 (95% confidence interval [0.0002-0.001]) and that the proportion of breast cancer cases in the general population due to BRCA1 is 5.3% below age 40 years, 2.2% between ages 40 and 49 years, and 1.1% between ages 50 and 70 years. The corresponding estimates for ovarian cancer are 5.7%, 4.6%, and 2.1%, respectively. Our results suggest that the majority of breast cancer families with less than four cases and no ovarian cancer are not due to rare highly penetrant genes such as BRCA1 but are more likely to be due either to chance or to more common genes of lower penetrance. 22 refs., 3 tabs.

  20. Mitochondrial localization, ELK-1 transcriptional regulation and Growth inhibitory functions of BRCA1, BRCA1a and BRCA1b proteins

    PubMed Central

    Maniccia, Anna W; Lewis, Catherine; Begum, Nurjahan; Xu, Jingyao; Cui, Jianqi; Chipitsyna, Galina; Aysola, Kartik; Reddy, Vaishali; Bhat, Ganapathy; Fujimura, Yasuo; Henderson, Beric; Reddy, E. Shyam P.; Rao, Veena N.

    2009-01-01

    BRCA1 is a tumor suppressor gene that is mutated in families with breast and ovarian cancer. Several BRCA1 splice variants are found in different tissues, but their subcellular localization and functions are poorly understood at the moment. We previously described BRCA1 splice variant BRCA1a to induce apoptosis and function as a tumor suppressor of triple negative breast, ovarian and prostate cancers. In this study we have analyzed the function of BRCA1 isoforms (BRCA1a and BRCA1b) and compared them to the wild type BRCA1 protein using several criteria like studying expression in normal and tumor cells by RNase protection assays, sub cellular localization/fractionation by immunofluorescence microscopy and western blot analysis, transcription regulation of biological relevant proteins and growth suppression in breast cancer cells. We are demonstrating for the first time that ectopically expressed GFP-tagged BRCA1, BRCA1a, and BRCA1b proteins are localized to the mitochondria, repress ELK-1 transcriptional activity and possess antiproliferative activity on breast cancer cells. These results suggest that the exon 9,10 and 11 sequences (aa 263 – 1365) which contain two nuclear localization signals, p53, Rb, c-Myc, γ- tubulin, Stat, Rad 51, Rad 50 binding domains, angiopoietin-1 repression domain are not absolutely required for mitochondrial localization and growth suppressor function of these proteins. Since mitochondrial dysfunction is a hallmark of cancer, we can speculate that the mitochondrial localization of BRCA1 proteins may be functionally significant in regulating both the mitochondrial DNA damage as well as apoptotic activity of BRCA1 proteins and mislocalization causes cancer. PMID:19170108

  1. Double heterozygosity in the BRCA1 and BRCA2 genes in the Jewish population

    PubMed Central

    Lavie, O.; Narod, S.; Lejbkowicz, F.; Dishon, S.; Goldberg, Y.; Gemer, O.; Rennert, G.

    2011-01-01

    Background: The frequency and characteristics of disease in individuals who concomitantly harbor pathogenic mutations in both BRCA1 and BRCA2 genes are not established. Materials and methods: Data were collected from the database of Clalit Health Services National Familial Cancer Consultation Service. Probands referred to this clinical service and their family members are routinely tested for the three Jewish founder mutations (BRCA1:185delAG, 5382insC, BRCA2:6174delT). In addition, carriers identified in a population-based cohort of all cases diagnosed with breast cancer in Israel in 1987–1988 allowed the estimation of the population frequency of this phenomenon. Results: In the clinic-based series of 1191 carriers of mutations in BRCA1 or BRCA2 belonging to 567 families, 22 males and females (1.85%) from 17 different families (3.0%) were found to harbor two different mutations. These included 18 individuals (1.51%) who concomitantly carried the 185delAG BRCA1 and the 6174delT BRCA2 mutations and four individuals (0.34%) who carried the 5382insC BRCA1 and the 6174delT mutations. All individuals were heterozygote carriers and none had a double mutation of both founder mutations in the BRCA1 gene itself. Seven of the 16 double carrier women (46.7%) had a personal history of breast carcinoma, diagnosed at a mean age of 44.6, compared with 372/926 (40.2%) carriers of a single mutation diagnosed with a mean age at diagnosis of 48.1 [odds ratio (OR) = 1.3, 95% confidence interval (CI) 0.4–4.0]. One case (6.7%) had a personal history of ovarian carcinoma diagnosed at the age of 53 compared with 55/926 (5.9%) of the women with single mutation (OR = 1.1, CI = 0.2–7.6). The frequency of double mutations in the population-based national breast cancer cohort was 2.2% of all carriers, and 0.3% of all breast cancer cases in the Ashkenazi population in the cohort. The mean age at diagnosis of breast cancer was younger in the carriers of two mutations. Conclusion: Double

  2. Hereditary Ovarian Cancer: Not Only BRCA 1 and 2 Genes

    PubMed Central

    Toss, Angela; Tomasello, Chiara; Razzaboni, Elisabetta; Contu, Giannina; Grandi, Giovanni; Cagnacci, Angelo; Schilder, Russell J.; Cortesi, Laura

    2015-01-01

    More than one-fifth of ovarian tumors have hereditary susceptibility and, in about 65–85% of these cases, the genetic abnormality is a germline mutation in BRCA genes. Nevertheless, several other suppressor genes and oncogenes have been associated with hereditary ovarian cancers, including the mismatch repair (MMR) genes in Lynch syndrome, the tumor suppressor gene, TP53, in the Li-Fraumeni syndrome, and several other genes involved in the double-strand breaks repair system, such as CHEK2, RAD51, BRIP1, and PALB2. The study of genetic discriminators and deregulated pathways involved in hereditary ovarian syndromes is relevant for the future development of molecular diagnostic strategies and targeted therapeutic approaches. The recent development and implementation of next-generation sequencing technologies have provided the opportunity to simultaneously analyze multiple cancer susceptibility genes, reduce the delay and costs, and optimize the molecular diagnosis of hereditary tumors. Particularly, the identification of mutations in ovarian cancer susceptibility genes in healthy women may result in a more personalized cancer risk management with tailored clinical and radiological surveillance, chemopreventive approaches, and/or prophylactic surgeries. On the other hand, for ovarian cancer patients, the identification of mutations may provide potential targets for biologic agents and guide treatment decision-making. PMID:26075229

  3. Hereditary ovarian cancer: not only BRCA 1 and 2 genes.

    PubMed

    Toss, Angela; Tomasello, Chiara; Razzaboni, Elisabetta; Contu, Giannina; Grandi, Giovanni; Cagnacci, Angelo; Schilder, Russell J; Cortesi, Laura

    2015-01-01

    More than one-fifth of ovarian tumors have hereditary susceptibility and, in about 65-85% of these cases, the genetic abnormality is a germline mutation in BRCA genes. Nevertheless, several other suppressor genes and oncogenes have been associated with hereditary ovarian cancers, including the mismatch repair (MMR) genes in Lynch syndrome, the tumor suppressor gene, TP53, in the Li-Fraumeni syndrome, and several other genes involved in the double-strand breaks repair system, such as CHEK2, RAD51, BRIP1, and PALB2. The study of genetic discriminators and deregulated pathways involved in hereditary ovarian syndromes is relevant for the future development of molecular diagnostic strategies and targeted therapeutic approaches. The recent development and implementation of next-generation sequencing technologies have provided the opportunity to simultaneously analyze multiple cancer susceptibility genes, reduce the delay and costs, and optimize the molecular diagnosis of hereditary tumors. Particularly, the identification of mutations in ovarian cancer susceptibility genes in healthy women may result in a more personalized cancer risk management with tailored clinical and radiological surveillance, chemopreventive approaches, and/or prophylactic surgeries. On the other hand, for ovarian cancer patients, the identification of mutations may provide potential targets for biologic agents and guide treatment decision-making. PMID:26075229

  4. Structure of BRCA1-BRCT/Abraxas Complex Reveals Phosphorylation-Dependent BRCT Dimerization at DNA Damage Sites

    PubMed Central

    Wu, Qian; Paul, Atanu; Su, Dan; Mehmood, Shahid; Foo, Tzeh Keong; Ochi, Takashi; Bunting, Emma L.; Xia, Bing; Robinson, Carol V.; Wang, Bin; Blundell, Tom L.

    2016-01-01

    Summary BRCA1 accumulation at DNA damage sites is an important step for its function in the DNA damage response and in DNA repair. BRCA1-BRCT domains bind to proteins containing the phosphorylated serine-proline-x-phenylalanine (pSPxF) motif including Abraxas, Bach1/FancJ, and CtIP. In this study, we demonstrate that ionizing radiation (IR)-induces ATM-dependent phosphorylation of serine 404 (S404) next to the pSPxF motif. Crystal structures of BRCT/Abraxas show that phosphorylation of S404 is important for extensive interactions through the N-terminal sequence outside the pSPxF motif and leads to formation of a stable dimer. Mutation of S404 leads to deficiency in BRCA1 accumulation at DNA damage sites and cellular sensitivity to IR. In addition, two germline mutations of BRCA1 are found to disrupt the dimer interface and dimer formation. Thus, we demonstrate a mechanism involving IR-induced phosphorylation and dimerization of the BRCT/Abraxas complex for regulating Abraxas-mediated recruitment of BRCA1 in response to IR. PMID:26778126

  5. Large-scale genomic analyses link reproductive aging to hypothalamic signaling, breast cancer susceptibility and BRCA1-mediated DNA repair.

    PubMed

    Day, Felix R; Ruth, Katherine S; Thompson, Deborah J; Lunetta, Kathryn L; Pervjakova, Natalia; Chasman, Daniel I; Stolk, Lisette; Finucane, Hilary K; Sulem, Patrick; Bulik-Sullivan, Brendan; Esko, Tõnu; Johnson, Andrew D; Elks, Cathy E; Franceschini, Nora; He, Chunyan; Altmaier, Elisabeth; Brody, Jennifer A; Franke, Lude L; Huffman, Jennifer E; Keller, Margaux F; McArdle, Patrick F; Nutile, Teresa; Porcu, Eleonora; Robino, Antonietta; Rose, Lynda M; Schick, Ursula M; Smith, Jennifer A; Teumer, Alexander; Traglia, Michela; Vuckovic, Dragana; Yao, Jie; Zhao, Wei; Albrecht, Eva; Amin, Najaf; Corre, Tanguy; Hottenga, Jouke-Jan; Mangino, Massimo; Smith, Albert V; Tanaka, Toshiko; Abecasis, Gonçalo R; Andrulis, Irene L; Anton-Culver, Hoda; Antoniou, Antonis C; Arndt, Volker; Arnold, Alice M; Barbieri, Caterina; Beckmann, Matthias W; Beeghly-Fadiel, Alicia; Benitez, Javier; Bernstein, Leslie; Bielinski, Suzette J; Blomqvist, Carl; Boerwinkle, Eric; Bogdanova, Natalia V; Bojesen, Stig E; Bolla, Manjeet K; Borresen-Dale, Anne-Lise; Boutin, Thibaud S; Brauch, Hiltrud; Brenner, Hermann; Brüning, Thomas; Burwinkel, Barbara; Campbell, Archie; Campbell, Harry; Chanock, Stephen J; Chapman, J Ross; Chen, Yii-Der Ida; Chenevix-Trench, Georgia; Couch, Fergus J; Coviello, Andrea D; Cox, Angela; Czene, Kamila; Darabi, Hatef; De Vivo, Immaculata; Demerath, Ellen W; Dennis, Joe; Devilee, Peter; Dörk, Thilo; Dos-Santos-Silva, Isabel; Dunning, Alison M; Eicher, John D; Fasching, Peter A; Faul, Jessica D; Figueroa, Jonine; Flesch-Janys, Dieter; Gandin, Ilaria; Garcia, Melissa E; García-Closas, Montserrat; Giles, Graham G; Girotto, Giorgia G; Goldberg, Mark S; González-Neira, Anna; Goodarzi, Mark O; Grove, Megan L; Gudbjartsson, Daniel F; Guénel, Pascal; Guo, Xiuqing; Haiman, Christopher A; Hall, Per; Hamann, Ute; Henderson, Brian E; Hocking, Lynne J; Hofman, Albert; Homuth, Georg; Hooning, Maartje J; Hopper, John L; Hu, Frank B; Huang, Jinyan; Humphreys, Keith; Hunter, David J; Jakubowska, Anna; Jones, Samuel E; Kabisch, Maria; Karasik, David; Knight, Julia A; Kolcic, Ivana; Kooperberg, Charles; Kosma, Veli-Matti; Kriebel, Jennifer; Kristensen, Vessela; Lambrechts, Diether; Langenberg, Claudia; Li, Jingmei; Li, Xin; Lindström, Sara; Liu, Yongmei; Luan, Jian'an; Lubinski, Jan; Mägi, Reedik; Mannermaa, Arto; Manz, Judith; Margolin, Sara; Marten, Jonathan; Martin, Nicholas G; Masciullo, Corrado; Meindl, Alfons; Michailidou, Kyriaki; Mihailov, Evelin; Milani, Lili; Milne, Roger L; Müller-Nurasyid, Martina; Nalls, Michael; Neale, Benjamin M; Nevanlinna, Heli; Neven, Patrick; Newman, Anne B; Nordestgaard, Børge G; Olson, Janet E; Padmanabhan, Sandosh; Peterlongo, Paolo; Peters, Ulrike; Petersmann, Astrid; Peto, Julian; Pharoah, Paul D P; Pirastu, Nicola N; Pirie, Ailith; Pistis, Giorgio; Polasek, Ozren; Porteous, David; Psaty, Bruce M; Pylkäs, Katri; Radice, Paolo; Raffel, Leslie J; Rivadeneira, Fernando; Rudan, Igor; Rudolph, Anja; Ruggiero, Daniela; Sala, Cinzia F; Sanna, Serena; Sawyer, Elinor J; Schlessinger, David; Schmidt, Marjanka K; Schmidt, Frank; Schmutzler, Rita K; Schoemaker, Minouk J; Scott, Robert A; Seynaeve, Caroline M; Simard, Jacques; Sorice, Rossella; Southey, Melissa C; Stöckl, Doris; Strauch, Konstantin; Swerdlow, Anthony; Taylor, Kent D; Thorsteinsdottir, Unnur; Toland, Amanda E; Tomlinson, Ian; Truong, Thérèse; Tryggvadottir, Laufey; Turner, Stephen T; Vozzi, Diego; Wang, Qin; Wellons, Melissa; Willemsen, Gonneke; Wilson, James F; Winqvist, Robert; Wolffenbuttel, Bruce B H R; Wright, Alan F; Yannoukakos, Drakoulis; Zemunik, Tatijana; Zheng, Wei; Zygmunt, Marek; Bergmann, Sven; Boomsma, Dorret I; Buring, Julie E; Ferrucci, Luigi; Montgomery, Grant W; Gudnason, Vilmundur; Spector, Tim D; van Duijn, Cornelia M; Alizadeh, Behrooz Z; Ciullo, Marina; Crisponi, Laura; Easton, Douglas F; Gasparini, Paolo P; Gieger, Christian; Harris, Tamara B; Hayward, Caroline; Kardia, Sharon L R; Kraft, Peter; McKnight, Barbara; Metspalu, Andres; Morrison, Alanna C; Reiner, Alex P; Ridker, Paul M; Rotter, Jerome I; Toniolo, Daniela; Uitterlinden, André G; Ulivi, Sheila; Völzke, Henry; Wareham, Nicholas J; Weir, David R; Yerges-Armstrong, Laura M; Price, Alkes L; Stefansson, Kari; Visser, Jenny A; Ong, Ken K; Chang-Claude, Jenny; Murabito, Joanne M; Perry, John R B; Murray, Anna

    2015-11-01

    Menopause timing has a substantial impact on infertility and risk of disease, including breast cancer, but the underlying mechanisms are poorly understood. We report a dual strategy in ∼70,000 women to identify common and low-frequency protein-coding variation associated with age at natural menopause (ANM). We identified 44 regions with common variants, including two regions harboring additional rare missense alleles of large effect. We found enrichment of signals in or near genes involved in delayed puberty, highlighting the first molecular links between the onset and end of reproductive lifespan. Pathway analyses identified major association with DNA damage response (DDR) genes, including the first common coding variant in BRCA1 associated with any complex trait. Mendelian randomization analyses supported a causal effect of later ANM on breast cancer risk (∼6% increase in risk per year; P = 3 × 10(-14)), likely mediated by prolonged sex hormone exposure rather than DDR mechanisms. PMID:26414677

  6. Large-scale genomic analyses link reproductive ageing to hypothalamic signaling, breast cancer susceptibility and BRCA1-mediated DNA repair

    PubMed Central

    Lunetta, Kathryn L.; Pervjakova, Natalia; Chasman, Daniel I.; Stolk, Lisette; Finucane, Hilary K.; Sulem, Patrick; Bulik-Sullivan, Brendan; Esko, Tõnu; Johnson, Andrew D.; Elks, Cathy E.; Franceschini, Nora; He, Chunyan; Altmaier, Elisabeth; Brody, Jennifer A.; Franke, Lude L.; Huffman, Jennifer E.; Keller, Margaux F.; McArdle, Patrick F.; Nutile, Teresa; Porcu, Eleonora; Robino, Antonietta; Rose, Lynda M.; Schick, Ursula M.; Smith, Jennifer A.; Teumer, Alexander; Traglia, Michela; Vuckovic, Dragana; Yao, Jie; Zhao, Wei; Albrecht, Eva; Amin, Najaf; Corre, Tanguy; Hottenga, Jouke-Jan; Mangino, Massimo; Smith, Albert V.; Tanaka, Toshiko; Abecasis, Goncalo; Andrulis, Irene L.; Anton-Culver, Hoda; Antoniou, Antonis C.; Arndt, Volker; Arnold, Alice M.; Barbieri, Caterina; Beckmann, Matthias W.; Beeghly-Fadiel, Alicia; Benitez, Javier; Bernstein, Leslie; Bielinski, Suzette J.; Blomqvist, Carl; Boerwinkle, Eric; Bogdanova, Natalia V.; Bojesen, Stig E.; Bolla, Manjeet K.; Borresen-Dale, Anne-Lise; Boutin, Thibaud S; Brauch, Hiltrud; Brenner, Hermann; Brüning, Thomas; Burwinkel, Barbara; Campbell, Archie; Campbell, Harry; Chanock, Stephen J.; Chapman, J. Ross; Chen, Yii-Der Ida; Chenevix-Trench, Georgia; Couch, Fergus J.; Coviello, Andrea D.; Cox, Angela; Czene, Kamila; Darabi, Hatef; De Vivo, Immaculata; Demerath, Ellen W.; Dennis, Joe; Devilee, Peter; Dörk, Thilo; dos-Santos-Silva, Isabel; Dunning, Alison M.; Eicher, John D.; Fasching, Peter A.; Faul, Jessica D.; Figueroa, Jonine; Flesch-Janys, Dieter; Gandin, Ilaria; Garcia, Melissa E.; García-Closas, Montserrat; Giles, Graham G.; Girotto, Giorgia G.; Goldberg, Mark S.; González-Neira, Anna; Goodarzi, Mark O.; Grove, Megan L.; Gudbjartsson, Daniel F.; Guénel, Pascal; Guo, Xiuqing; Haiman, Christopher A.; Hall, Per; Hamann, Ute; Henderson, Brian E.; Hocking, Lynne J.; Hofman, Albert; Homuth, Georg; Hooning, Maartje J.; Hopper, John L.; Hu, Frank B.; Huang, Jinyan; Humphreys, Keith; Hunter, David J.; Jakubowska, Anna; Jones, Samuel E.; Kabisch, Maria; Karasik, David; Knight, Julia A.; Kolcic, Ivana; Kooperberg, Charles; Kosma, Veli-Matti; Kriebel, Jennifer; Kristensen, Vessela; Lambrechts, Diether; Langenberg, Claudia; Li, Jingmei; Li, Xin; Lindström, Sara; Liu, Yongmei; Luan, Jian’an; Lubinski, Jan; Mägi, Reedik; Mannermaa, Arto; Manz, Judith; Margolin, Sara; Marten, Jonathan; Martin, Nicholas G.; Masciullo, Corrado; Meindl, Alfons; Michailidou, Kyriaki; Mihailov, Evelin; Milani, Lili; Milne, Roger L.; Müller-Nurasyid, Martina; Nalls, Michael; Neale, Ben M.; Nevanlinna, Heli; Neven, Patrick; Newman, Anne B.; Nordestgaard, Børge G.; Olson, Janet E.; Padmanabhan, Sandosh; Peterlongo, Paolo; Peters, Ulrike; Petersmann, Astrid; Peto, Julian; Pharoah, Paul D.P.; Pirastu, Nicola N.; Pirie, Ailith; Pistis, Giorgio; Polasek, Ozren; Porteous, David; Psaty, Bruce M.; Pylkäs, Katri; Radice, Paolo; Raffel, Leslie J.; Rivadeneira, Fernando; Rudan, Igor; Rudolph, Anja; Ruggiero, Daniela; Sala, Cinzia F.; Sanna, Serena; Sawyer, Elinor J.; Schlessinger, David; Schmidt, Marjanka K.; Schmidt, Frank; Schmutzler, Rita K.; Schoemaker, Minouk J.; Scott, Robert A.; Seynaeve, Caroline M.; Simard, Jacques; Sorice, Rossella; Southey, Melissa C.; Stöckl, Doris; Strauch, Konstantin; Swerdlow, Anthony; Taylor, Kent D.; Thorsteinsdottir, Unnur; Toland, Amanda E.; Tomlinson, Ian; Truong, Thérèse; Tryggvadottir, Laufey; Turner, Stephen T.; Vozzi, Diego; Wang, Qin; Wellons, Melissa; Willemsen, Gonneke; Wilson, James F.; Winqvist, Robert; Wolffenbuttel, Bruce B.H.R.; Wright, Alan F.; Yannoukakos, Drakoulis; Zemunik, Tatijana; Zheng, Wei; Zygmunt, Marek; Bergmann, Sven; Boomsma, Dorret I.; Buring, Julie E.; Ferrucci, Luigi; Montgomery, Grant W.; Gudnason, Vilmundur; Spector, Tim D.; van Duijn, Cornelia M; Alizadeh, Behrooz Z.; Ciullo, Marina; Crisponi, Laura; Easton, Douglas F.; Gasparini, Paolo P.; Gieger, Christian; Harris, Tamara B.; Hayward, Caroline; Kardia, Sharon L.R.; Kraft, Peter; McKnight, Barbara; Metspalu, Andres; Morrison, Alanna C.; Reiner, Alex P.; Ridker, Paul M.; Rotter, Jerome I.; Toniolo, Daniela; Uitterlinden, André G.; Ulivi, Sheila; Völzke, Henry; Wareham, Nicholas J.; Weir, David R.; Yerges-Armstrong, Laura M.; Price, Alkes L.; Stefansson, Kari; Visser, Jenny A.; Ong, Ken K.; Chang-Claude, Jenny; Murabito, Joanne M.; Perry, John R.B.; Murray, Anna

    2015-01-01

    Menopause timing has a substantial impact on infertility and risk of disease, including breast cancer, but the underlying mechanisms are poorly understood. We report a dual strategy in ~70,000 women to identify common and low-frequency protein-coding variation associated with age at natural menopause (ANM). We identified 44 regions with common variants, including two harbouring additional rare missense alleles of large effect. We found enrichment of signals in/near genes involved in delayed puberty, highlighting the first molecular links between the onset and end of reproductive lifespan. Pathway analyses revealed a major association with DNA damage-response (DDR) genes, including the first common coding variant in BRCA1 associated with any complex trait. Mendelian randomisation analyses supported a causal effect of later ANM on breast cancer risk (~6% risk increase per-year, P=3×10−14), likely mediated by prolonged sex hormone exposure, rather than DDR mechanisms. PMID:26414677

  7. Identification and frequency of the rs12516 and rs8176318 BRCA1 gene polymorphisms among different populations

    PubMed Central

    YANG, FANG; CHEN, FENGXIA; XU, JIN; GUAN, XIAOXIANG

    2016-01-01

    Genetic mutation of breast cancer 1 (BRCA1) is one of the most notable factors responsible for a proportion of breast cancer cases. BRCA1 encodes a 1,863-amino acid protein and functions as a negative regulator of tumor growth. Thus, investigation of the underlying mechanisms that regulate BRCA1 gene expression provide further insight into possible targets for breast cancer therapy. Previous studies have demonstrated that the genetic variants in the BRCA1 3′ untranslated region (3′UTR), in addition to the cytosine-phosphate-guanine (CpG) islands in the promoter region, are significantly associated with breast cancer risk; however, the role of single nucleotide polymorphisms (SNPs) in the BRCA1 3′UTR remains unclear. The present study aimed to investigate the association between SNPs and BRCA1 mRNA expression levels. Bioinformatics analysis demonstrated that 2 SNPs in the BRCA1 3′UTR (rs12516 and rs8176318 with putative microRNA binding sites) were significantly correlated with mRNA expression in lymphoblastoid cell lines (P=2.55×10-4 and P=8.78×10−5, respectively). Furthermore, the genotype frequency distribution varied between populations worldwide. In addition, 3 CpG islands and several transcription factor binding sites in the BRCA1 promoter region were established. The identification of such polymorphisms and CpG islands may aid in designing improved therapeutic strategies to treat patients with BRCA1-associated breast cancer. PMID:27073502

  8. Identification and evaluation of 55 genetic variations in the BRCA1 and the BRCA2 genes of patients from 50 Japanese breast cancer families.

    PubMed

    Kawahara, Masanori; Sakayori, Masato; Shiraishi, Kazuko; Nomizu, Tadashi; Takeda, Motohiro; Abe, Rikiya; Ohuchi, Noriaki; Takenoshita, Seiichi; Ishioka, Chikashi

    2004-01-01

    We sequenced approximately 23 kb genomic regions containing all the coding exons and their franking introns of two breast cancer susceptibility genes, BRCA1 and BRCA2, of 55 individuals from 50 unrelated Japanese breast cancer families. We identified 55 single-nucleotide polymorphisms (SNPs) (21 in BRCA1 and 34 in BRCA2) containing nine pathogenic protein-truncating mutations (four in BRCA1 and five in BRCA2 from ten patients). Among the remaining 46 SNPs, allele frequencies of 40 were examined in both the breast cancer patients and 28 healthy volunteers with no breast cancer family history by PCR-RFLP or by direct DNA sequencing. Twenty-eight SNPs were common and were also found in the healthy volunteers and/or a SNP database. The remaining 18 were rare (allele frequency <0.05) and were not found in the healthy volunteers and/or the database. The pathogenic significance of these coding SNPs (cSNPs) remains to be clarified. The SNP information from this study will be useful in the future genetic testing of both BRCA1 and BRCA2 genes in the Japanese population. PMID:15168169

  9. Mutations in BRCA1 and BRCA2 in breast cancer families: Are there more breast cancer-susceptibility genes?

    SciTech Connect

    Serova, O.M.; Mazoyer, S.; Putet, N.

    1997-03-01

    To estimate the proportion of breast cancer families due to BRCA1 or BRCA2, we performed mutation screening of the entire coding regions of both genes supplemented with linkage analysis of 31 families, 8 containing male breast cancers and 23 site-specific female breast cancer. A combination of protein-truncation test and SSCP or heteroduplex analyses was used for mutation screening complemented, where possible, by the analysis of expression level of BRCA1 and BRCA2 alleles. Six of the eight families with male breast cancer revealed frameshift mutations, two in BRCA1 and four in BRCA2. Although most families with female site-specific breast cancers were thought to be due to mutations in either BRCA1 or BRCA2, we identified only eight mutations in our series of 23 site-specific female breast cancer families (34%), four in BRCA1 and four in BRCA2. According to the posterior probabilities calculated for mutation-negative families, based on linkage data and mutation screening results, we would expect 8-10 site-specific female breast cancer families of our series to be due to neither BRCA1 nor BRCA2. Thus, our results suggest the existence of at least one more major breast cancer-susceptibility gene. 24 refs., 1 fig., 3 tabs.

  10. The contribution of deleterious germline mutations in BRCA1, BRCA2 and the mismatch repair genes to ovarian cancer in the population

    PubMed Central

    Song, Honglin; Cicek, Mine S.; Dicks, Ed; Harrington, Patricia; Ramus, Susan J.; Cunningham, Julie M.; Fridley, Brooke L.; Tyrer, Jonathan P.; Alsop, Jennifer; Jimenez-Linan, Mercedes; Gayther, Simon A.; Goode, Ellen L.; Pharoah, Paul D.P.

    2014-01-01

    The aim of this study was to estimate the contribution of deleterious mutations in BRCA1, BRCA2, MLH1, MSH2, MSH6 and PMS2 to invasive epithelial ovarian cancer (EOC) in the population. The coding sequence and splice site boundaries of all six genes were amplified in germline DNA from 2240 invasive EOC cases and 1535 controls. Barcoded fragment libraries were sequenced using the Illumina GAII or HiSeq and sequence data for each subject de-multiplexed prior to interpretation. GATK and Annovar were used for variant detection and annotation. After quality control 2222 cases (99.2%) and 1528 controls (99.5%) were included in the final analysis. We identified 193 EOC cases (8.7%) carrying a deleterious mutation in at least one gene compared with 10 controls (0.65%). Mutations were most frequent in BRCA1 and BRCA2, with 84 EOC cases (3.8%) carrying a BRCA1 mutation and 94 EOC cases (4.2%) carrying a BRCA2 mutation. The combined BRCA1 and BRCA2 mutation prevalence was 11% in high-grade serous disease. Seventeen EOC cases carried a mutation in a mismatch repair gene, including 10 MSH6 mutation carriers (0.45%) and 4 MSH2 mutation carriers (0.18%). At least 1 in 10 women with high-grade serous EOC has a BRCA1 or BRCA2 mutation. The development of next generation sequencing technologies enables rapid mutation screening for multiple susceptibility genes at once, suggesting that routine clinical testing of all incidence cases should be considered. PMID:24728189

  11. Streamlined ion torrent PGM-based diagnostics: BRCA1 and BRCA2 genes as a model

    PubMed Central

    Tarabeux, Julien; Zeitouni, Bruno; Moncoutier, Virginie; Tenreiro, Henrique; Abidallah, Khadija; Lair, Séverine; Legoix-Né, Patricia; Leroy, Quentin; Rouleau, Etienne; Golmard, Lisa; Barillot, Emmanuel; Stern, Marc-Henri; Rio-Frio, Thomas; Stoppa-Lyonnet, Dominique; Houdayer, Claude

    2014-01-01

    To meet challenges in terms of throughput and turnaround time, many diagnostic laboratories are shifting from Sanger sequencing to higher throughput next-generation sequencing (NGS) platforms. Bearing in mind that the performance and quality criteria expected from NGS in diagnostic or research settings are strikingly different, we have developed an Ion Torrent's PGM-based routine diagnostic procedure for BRCA1/2 sequencing. The procedure was first tested on a training set of 62 control samples, and then blindly validated on 77 samples in parallel with our routine technique. The training set was composed of difficult cases, for example, insertions and/or deletions of various sizes, large-scale rearrangements and, obviously, mutations occurring in homopolymer regions. We also compared two bioinformatic solutions in this diagnostic context, an in-house academic pipeline and the commercially available NextGene software (Softgenetics). NextGene analysis provided higher sensitivity, as four previously undetected single-nucleotide variations were found. Regarding specificity, an average of 1.5 confirmatory Sanger sequencings per patient was needed for complete BRCA1/2 screening. Large-scale rearrangements were identified by two distinct analyses, that is, bioinformatics and fragment analysis with electrophoresis profile comparison. Turnaround time was enhanced, as a series of 30 patients were sequenced by one technician, making the results available for the clinician in 10 working days following blood sampling. BRCA1/2 genes are a good model, representative of the difficulties commonly encountered in diagnostic settings, which is why we believe our findings are of interest for the whole community, and the pipeline described can be adapted by any user of PGM for diagnostic purposes. PMID:23942203

  12. Multicolor FISH mapping with Alu-PCR-amplified YAC clone DNA determines the order of markers in the BRCA1 region on chromosome 17q12-q21

    SciTech Connect

    Flejter, W.J.; Glover, T.W.; Barcroft, C.L.; Guo, Sun Wei; Boehnke, M.; Chandrasekharappa, S.; Collins, F.S. Howard Hughes Medical Institute, Ann Arbor, MI ); Lynch, E.D. ); Hayes, S. ); Weber, B.L. )

    1993-09-01

    A gene designated BRCA1, implicated in the susceptibility to early-onset familial breast cancer, has recently been localized to chromosome 17q12-q21. To date, the order of DNA markers mapped within this region has been based on genetic linkage analysis. The authors report the use of multicolor fluorescence in situ hybridization to establish a physically based map of five polymorphic DNA markers and 10 cloned genes spanning this region. Three cosmid clones and Alu-PCR-Generated products derived from 12 yeast artificial chromosome clones representing each of these markers were used in two-color mapping experiments to determine an initial proximity of markers relative to each other on metaphase chromosomes. Interphase mapping was then employed to determine the order and orientation of closely spaced loci by direct visualization of fluorescent signals following hybridization of three probes, each detected in a different color. Statistical analysis of the combined data suggests that the order of markers in the BRCA1 regions is cen-THRA1-TOP2-GAS-OF2-17HSD-248yg9-RNU2-OF3-PPY/p131-EPB3-Mfd188-WNT3-HOX2-GP3A-tel. This map is consistent with that determined by radiation-reduced hybrid mapping and will facilitate positional cloning strategies in efforts to isolate and characterize the BRCA1 gene. 27 refs., 2 figs., 3 tabs.

  13. Suppression of BRCA1 sensitizes cells to proteasome inhibitors

    PubMed Central

    Gu, Y; Bouwman, P; Greco, D; Saarela, J; Yadav, B; Jonkers, J; Kuznetsov, S G

    2014-01-01

    BRCA1 is a multifunctional protein best known for its role in DNA repair and association with breast and ovarian cancers. To uncover novel biologically significant molecular functions of BRCA1, we tested a panel of 198 approved and experimental drugs to inhibit growth of MDA-MB-231 breast cancer cells depleted for BRCA1 by siRNA. 26S proteasome inhibitors bortezomib and carfilzomib emerged as a new class of selective BRCA1-targeting agents. The effect was confirmed in HeLa and U2OS cancer cell lines using two independent siRNAs, and in mouse embryonic stem (ES) cells with inducible deletion of Brca1. Bortezomib treatment did not cause any increase in nuclear foci containing phosphorylated histone H2AX, and knockdown of BRCA2 did not entail sensitivity to bortezomib, suggesting that the DNA repair function of BRCA1 may not be directly involved. We found that a toxic effect of bortezomib on BRCA1-depleted cells is mostly due to deregulated cell cycle checkpoints mediated by RB1-E2F pathway and 53BP1. Similar to BRCA1, depletion of RB1 also conferred sensitivity to bortezomib, whereas suppression of E2F1 or 53BP1 together with BRCA1 reduced induction of apoptosis after bortezomib treatment. A gene expression microarray study identified additional genes activated by bortezomib treatment only in the context of inactivation of BRCA1 including a critical involvement of the ERN1-mediated unfolded protein response. Our data indicate that BRCA1 has a novel molecular function affecting cell cycle checkpoints in a manner dependent on the 26S proteasome activity. PMID:25522274

  14. Suppression of BRCA1 sensitizes cells to proteasome inhibitors.

    PubMed

    Gu, Y; Bouwman, P; Greco, D; Saarela, J; Yadav, B; Jonkers, J; Kuznetsov, S G

    2014-01-01

    BRCA1 is a multifunctional protein best known for its role in DNA repair and association with breast and ovarian cancers. To uncover novel biologically significant molecular functions of BRCA1, we tested a panel of 198 approved and experimental drugs to inhibit growth of MDA-MB-231 breast cancer cells depleted for BRCA1 by siRNA. 26S proteasome inhibitors bortezomib and carfilzomib emerged as a new class of selective BRCA1-targeting agents. The effect was confirmed in HeLa and U2OS cancer cell lines using two independent siRNAs, and in mouse embryonic stem (ES) cells with inducible deletion of Brca1. Bortezomib treatment did not cause any increase in nuclear foci containing phosphorylated histone H2AX, and knockdown of BRCA2 did not entail sensitivity to bortezomib, suggesting that the DNA repair function of BRCA1 may not be directly involved. We found that a toxic effect of bortezomib on BRCA1-depleted cells is mostly due to deregulated cell cycle checkpoints mediated by RB1-E2F pathway and 53BP1. Similar to BRCA1, depletion of RB1 also conferred sensitivity to bortezomib, whereas suppression of E2F1 or 53BP1 together with BRCA1 reduced induction of apoptosis after bortezomib treatment. A gene expression microarray study identified additional genes activated by bortezomib treatment only in the context of inactivation of BRCA1 including a critical involvement of the ERN1-mediated unfolded protein response. Our data indicate that BRCA1 has a novel molecular function affecting cell cycle checkpoints in a manner dependent on the 26S proteasome activity. PMID:25522274

  15. BRCA1 and Oxidative Stress

    PubMed Central

    Yi, Yong Weon; Kang, Hyo Jin; Bae, Insoo

    2014-01-01

    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. PMID:24704793

  16. Inhibition of RNA polymerase III transcription by BRCA1.

    PubMed

    Veras, Ingrid; Rosen, Eliot M; Schramm, Laura

    2009-04-01

    RNA polymerase III (RNA pol III) transcribes structural RNAs involved in RNA processing (U6 snRNA) and translation (tRNA), thereby regulating the growth rate of cells. Proper initiation by RNA pol III requires the transcription factor TFIIIB. Gene-external U6 snRNA transcription requires TFIIIB consisting of Bdp1, TBP, and Brf2. Transcription from the gene-internal tRNA promoter requires TFIIIB composed of Bdp1, TBP, and Brf1. TFIIIB is a target of tumor suppressors, including PTEN, ARF, p53, and RB, and RB-related pocket proteins. Breast cancer susceptibility gene 1 (BRCA1) tumor suppressor plays a role in DNA repair, cell cycle regulation, apoptosis, genome integrity, and ubiquitination. BRCA1 has a conserved amino-terminal RING domain, an activation domain 1 (AD1), and an acidic carboxyl-terminal domain (BRCA1 C-terminal region). In Saccharomyces cerevisiae, TFIIB interacts with the BRCA1 C-terminal region domain of Fcp1p, an RNA polymerase II phosphatase. The TFIIIB subunits Brf1 and Brf2 are structurally similar to TFIIB. Hence, we hypothesize that RNA pol III may be regulated by BRCA1 via the TFIIB family members Brf1 and Brf2. Here we report that: (1) BRCA1 inhibits both VAI (tRNA) and U6 snRNA RNA pol III transcription; (2) the AD1 of BRCA1 is responsible for inhibition of U6 snRNA transcription, whereas the RING domain and AD1 of BRCA1 are required for VAI transcription inhibition; and (3) overexpression of Brf1 and Brf2 alleviates inhibition of U6 snRNA and VAI transcription by BRCA1. Taken together, these data suggest that BRCA1 is a general repressor of RNA pol III transcription. PMID:19361418

  17. Frequency of 5382insC mutation of BRCA1 gene among breast cancer patients: an experience from Eastern India.

    PubMed

    Chakraborty, Abhijit; Mukhopadhyay, Ashis; Bhattacharyya, Deboshree; Bose, Chinmoy Kr; Choudhuri, Keya; Mukhopadhyay, Soma; Basak, Jayasri

    2013-09-01

    The incidence of breast cancer in India is on the rise and is rapidly becoming the number one cancer in females pushing the cervical cancer to the second position. The mutations in two breast cancer susceptibility genes, BRCA1 and BRCA2, are frequently associated with familial breast cancer. The main objective of the study was to determine the frequency of the mutation 5382insC in BRCA1 of eastern Indian breast cancer patients and also study the hormonal receptor status and histopathology of the patients. Altogether 92 patients affected with breast cancer were included in this study. ARMS-PCR based amplification was used to detect the presence of mutation. The mutations were considered only after pedigree analysis. Out of 92 patients (age range: 20-77 years) with family history (57 individuals) and without family history (35 individuals) were screened. Fifty controls have been systematically investigated. Seven patients and two family members were found to be carriers of 5382insC mutation in BRCA1 gene. We have found 42.64 % ER(-)/PR(-) cancer and 20.58 % triple negative cancer. Invasive ductal carcinoma is the most common histology among the investigated individuals. The presented data confirm a noticeable contribution of BRCA1 5382insC mutation in BC development in Eastern India, which may justify an extended BRCA1 5382insC testing within this patient population. We found HER-2/neu negativity and BRCA1 positivity associated with familial breast cancer. From the hospital's patient history, it was revealed that the age of menarche plays an important role in development of breast cancer. PMID:23232912

  18. Interaction of BARD1 and HP1 is required for BRCA1 retention at sites of DNA damage

    PubMed Central

    Wu, Wenwen; Nishikawa, Hiroyuki; Fukuda, Takayo; Vittal, Vinayak; Asano, Masahide; Miyoshi, Yasuo; Klevit, Rachel E.; Ohta, Tomohiko

    2016-01-01

    Stable retention of BRCA1/BARD1 complexes at sites of DNA damage is required for the proper response to DNA double-strand breaks (DSB). Here, we demonstrate that the BRCT domain of BARD1 is crucial for its retention through interaction with HP1. In response to DNA damage, BARD1 interacts with Lys9-dimethylated histone H3 (H3K9me2) in an ATM-dependent but RNF168-independent manner. This interaction is mediated primarily by HP1γ. A conserved HP1-binding motif in the BARD1 BRCT domain directly interacted with the chromoshadow domain of HP1 in vitro. Mutations in this motif (or simultaneous depletion of all three HP1 isoforms) disrupted retention of BARD1, BRCA1 and CtIP at DSB sites and allowed ectopic accumulation of RIF1, an effector of non-homologous end joining, at damaged loci in S phase. UNC0638, a small molecule inhibitor of histone lysine methyltransferase (HKMT), abolished retention and cooperated with the poly(ADP-ribose) polymerase inhibitor olaparib to block cancer cell growth. Taken together, our findings show how BARD1 promotes retention of the BRCA1/BARD1 complex at damaged DNA sites, and suggest the use of HKMT inhibitors to leverage the application of PARP inhibitors to treat breast cancer. PMID:25634209

  19. Analysis of PALB2 Gene in BRCA1/BRCA2 Negative Spanish Hereditary Breast/Ovarian Cancer Families with Pancreatic Cancer Cases

    PubMed Central

    de la Hoya, Miguel; Osorio, Ana; Diez, Orland; Miramar, María Dolores; Infante, Mar; Martinez-Bouzas, Cristina; Torres, Asunción; Lasa, Adriana; Llort, Gemma; Brunet, Joan; Graña, Begoña; Perez Segura, Pedro; Garcia, María José; Gutiérrez-Enríquez, Sara; Carracedo, Ángel; Tejada, María-Isabel; Velasco, Eladio A.; Calvo, María-Teresa; Balmaña, Judith; Benitez, Javier; Caldés, Trinidad

    2013-01-01

    Background The PALB2 gene, also known as FANCN, forms a bond and co-localizes with BRCA2 in DNA repair. Germline mutations in PALB2 have been identified in approximately 1% of familial breast cancer and 3–4% of familial pancreatic cancer. The goal of this study was to determine the prevalence of PALB2 mutations in a population of BRCA1/BRCA2 negative breast cancer patients selected from either a personal or family history of pancreatic cancer. Methods 132 non-BRCA1/BRCA2 breast/ovarian cancer families with at least one pancreatic cancer case were included in the study. PALB2 mutational analysis was performed by direct sequencing of all coding exons and intron/exon boundaries, as well as multiplex ligation-dependent probe amplification. Results Two PALB2 truncating mutations, the c.1653T>A (p.Tyr551Stop) previously reported, and c.3362del (p.Gly1121ValfsX3) which is a novel frameshift mutation, were identified. Moreover, several PALB2 variants were detected; some of them were predicted as pathological by bioinformatic analysis. Considering truncating mutations, the prevalence rate of our population of BRCA1/2-negative breast cancer patients with pancreatic cancer is 1.5%. Conclusions The prevalence rate of PALB2 mutations in non-BRCA1/BRCA2 breast/ovarian cancer families, selected from either a personal or family pancreatic cancer history, is similar to that previously described for unselected breast/ovarian cancer families. Future research directed towards identifying other gene(s) involved in the development of breast/pancreatic cancer families is required. PMID:23935836

  20. The importance of BRCA1 and BRCA2 genes mutations in breast cancer development

    PubMed Central

    Mehrgou, Amir; Akouchekian, Mansoureh

    2016-01-01

    Many factors including genetic, environmental, and acquired are involved in breast cancer development across various societies. Among all of these factors in families with a history of breast cancer throughout several generations, genetics, like predisposing genes to develop this disease, should be considered more. Early detection of mutation carriers in these genes, in turn, can play an important role in its prevention. Because this disease has a high prevalence in half of the global population, female screening of reported mutations in predisposing genes, which have been seen in breast cancer patients, seems necessary. In this review, a number of mutations in two predisposing genes (BRCA1 and BRCA2) that occurred in patients with a family history was investigated. We studied published articles about mutations in genes predisposed to breast cancer between 2000 and 2015. We then summarized and classified reported mutations in these two genes to recommend some exons which have a high potential to mutate. According to previous studies, exons have been reported as most mutated exons presented in this article. Considering the large size and high cost of screening all exons in these two genes in patients with a family history, especially in developing countries, the results of this review article can be beneficial and helpful in the selection of exon to screen for patients with this disease. PMID:27493913

  1. The importance of BRCA1 and BRCA2 genes mutations in breast cancer development.

    PubMed

    Mehrgou, Amir; Akouchekian, Mansoureh

    2016-01-01

    Many factors including genetic, environmental, and acquired are involved in breast cancer development across various societies. Among all of these factors in families with a history of breast cancer throughout several generations, genetics, like predisposing genes to develop this disease, should be considered more. Early detection of mutation carriers in these genes, in turn, can play an important role in its prevention. Because this disease has a high prevalence in half of the global population, female screening of reported mutations in predisposing genes, which have been seen in breast cancer patients, seems necessary. In this review, a number of mutations in two predisposing genes (BRCA1 and BRCA2) that occurred in patients with a family history was investigated. We studied published articles about mutations in genes predisposed to breast cancer between 2000 and 2015. We then summarized and classified reported mutations in these two genes to recommend some exons which have a high potential to mutate. According to previous studies, exons have been reported as most mutated exons presented in this article. Considering the large size and high cost of screening all exons in these two genes in patients with a family history, especially in developing countries, the results of this review article can be beneficial and helpful in the selection of exon to screen for patients with this disease. PMID:27493913

  2. BRCA1-BARD1 complexes are required for p53Ser-15 phosphorylation and a G1/S arrest following ionizing radiation-induced DNA damage.

    PubMed

    Fabbro, Megan; Savage, Kienan; Hobson, Karen; Deans, Andrew J; Powell, Simon N; McArthur, Grant A; Khanna, Kum Kum

    2004-07-23

    BRCA1 is a major player in the DNA damage response. This is evident from its loss, which causes cells to become sensitive to a wide variety of DNA damaging agents. The major BRCA1 binding partner, BARD1, is also implicated in the DNA damage response, and recent reports indicate that BRCA1 and BARD1 co-operate in this pathway. In this report, we utilized small interfering RNA to deplete BRCA1 and BARD1 to demonstrate that the BRCA1-BARD1 complex is required for ATM/ATR (ataxia-telangiectasia-mutated/ATM and Rad3-related)-mediated phosphorylation of p53(Ser-15) following IR- and UV radiation-induced DNA damage. In contrast, phosphorylation of a number of other ATM/ATR targets including H2AX, Chk2, Chk1, and c-jun does not depend on the presence of BRCA1-BARD1 complexes. Moreover, prior ATM/ATR-dependent phosphorylation of BRCA1 at Ser-1423 or Ser-1524 regulates the ability of ATM/ATR to phosphorylate p53(Ser-15) efficiently. Phosphorylation of p53(Ser-15) is necessary for an IR-induced G(1)/S arrest via transcriptional induction of the cyclin-dependent kinase inhibitor p21. Consistent with these data, repressing p53(Ser-15) phosphorylation by BRCA1-BARD1 depletion compromises p21 induction and the G(1)/S checkpoint arrest in response to IR but not UV radia-tion. These findings suggest that BRCA1-BARD1 complexes act as an adaptor to mediate ATM/ATR-directed phosphorylation of p53, influencing G(1)/S cell cycle progression after DNA damage. PMID:15159397

  3. BRCA1/2 testing in newly diagnosed breast and ovarian cancer patients without prior genetic counselling: the DNA-BONus study.

    PubMed

    Høberg-Vetti, Hildegunn; Bjorvatn, Cathrine; Fiane, Bent E; Aas, Turid; Woie, Kathrine; Espelid, Helge; Rusken, Tone; Eikesdal, Hans Petter; Listøl, Wenche; Haavind, Marianne T; Knappskog, Per M; Haukanes, Bjørn Ivar; Steen, Vidar M; Hoogerbrugge, Nicoline

    2016-06-01

    Germline BRCA1/2 testing of breast and ovarian cancer patients is growing rapidly as the result affects both treatment and cancer prevention in patients and relatives. Through the DNA-BONus study we offered BRCA1/2 testing and familial risk assessment to all new patients with breast (N=893) or ovarian (N=122) cancer diagnosed between September 2012 and April 2015, irrespective of family history or age, and without prior face-to-face genetic counselling. BRCA1/2 testing was accepted by 405 (45.4%) and 83 (68.0%) of the patients with breast or ovarian cancer, respectively. A pathogenic BRCA1/2 variant was found in 7 (1.7%) of the breast cancer patients and 19 (22.3%) of the ovarian cancer patients. In retrospect, all BRCA1/2 mutation carriers appeared to fulfill current criteria for BRCA1/2 testing. Hospital Anxiety and Depression Scale (HADS) scores showed that the mean levels of anxiety and depression were comparable to those reported for breast and gynecological cancer patients in general, with a significant drop in anxiety symptoms during a 6-month follow-up period, during which the test result was forwarded to the patients. These results show that BRCA1/2 testing is well accepted in newly diagnosed breast and ovarian cancer patients. Current test criteria based on age and family history are sufficient to identify most BRCA1/2 mutation carriers among breast cancer patients. We recommend germline BRCA1/2 testing in all patients with epithelial ovarian cancer because of the high prevalence of pathogenic BRCA1/2 variants. PMID:26350514

  4. Brca1 deficiency causes bone marrow failure and spontaneous hematologic malignancies in mice.

    PubMed

    Vasanthakumar, Aparna; Arnovitz, Stephen; Marquez, Rafael; Lepore, Janet; Rafidi, George; Asom, Anase; Weatherly, Madison; Davis, Elizabeth M; Neistadt, Barbara; Duszynski, Robert; Vardiman, James W; Le Beau, Michelle M; Godley, Lucy A; Churpek, Jane E

    2016-01-21

    BRCA1 is critical for maintenance of genomic stability and interacts directly with several proteins that regulate hematopoietic stem cell function and are part of the Fanconi anemia (FA) double-strand break DNA repair pathway. The effects of complete BRCA1 deficiency on bone marrow (BM) function are unknown. To test the hypothesis that Brca1 is essential in hematopoiesis, we developed a conditional mouse model with Mx1-Cre-mediated Brca1 deletion. Mice lacking Brca1 in the BM have baseline cytopenias and develop spontaneous bone marrow failure or diverse hematologic malignancies by 6 months of age. Brca1(-/-) BM cells have a reduced capacity to form hematopoietic colonies in vitro and to reconstitute hematopoiesis in irradiated recipients, consistent with a hematopoietic progenitor functional defect. Brca1(-/-) BM cells also show FA-like hypersensitivity to the DNA crosslinking agent mitomycin C, and karyotypes feature genomic instability. Taken together, our results show that loss of Brca1 in murine BM causes hematopoietic defects similar to those seen in people with FA, which provides strong evidence that Brca1 is critical for normal hematopoiesis and that Brca1 is a bona fide FA-like gene. PMID:26644450

  5. Persistent Activation of NF-κB in BRCA1-Deficient Mammary Progenitors Drives Aberrant Proliferation and Accumulation of DNA Damage.

    PubMed

    Sau, Andrea; Lau, Rosanna; Cabrita, Miguel A; Nolan, Emma; Crooks, Peter A; Visvader, Jane E; Pratt, M A Christine

    2016-07-01

    Human BRCA1 mutation carriers and BRCA1-deficient mouse mammary glands contain an abnormal population of mammary luminal progenitors that can form 3D colonies in a hormone-independent manner. The intrinsic cellular regulatory defect in these presumptive breast cancer precursors is not known. We have discovered that nuclear factor kappaB (NF-κB) (p52/RelB) is persistently activated in a subset of BRCA1-deficient mammary luminal progenitors. Hormone-independent luminal progenitor colony formation required NF-κB, ataxia telangiectasia-mutated (ATM), and the inhibitor of kappaB kinase, IKKα. Progesterone (P4)-stimulated proliferation resulted in a marked enhancement of DNA damage foci in Brca1(-/-) mouse mammary. In vivo, NF-κB inhibition prevented recovery of Brca1(-/-) hormone-independent colony-forming cells. The majority of human BRCA1(mut/+) mammary glands showed marked lobular expression of nuclear NF-κB. We conclude that the aberrant proliferative capacity of Brca1(-/-) luminal progenitor cells is linked to the replication-associated DNA damage response, where proliferation of mammary progenitors is perpetuated by damage-induced, autologous NF-κB signaling. PMID:27292187

  6. The BRCA1-interacting protein, Abraxas, is required for genomic stability and tumor suppression

    PubMed Central

    Castillo, Andy; Paul, Atanu; Sun, Baohua; Huang, Ting Hsiang; Wang, Yucai; Yazinski, Stephanie A.; Tyler, Jessica; Li, Lei; You, M James; Zou, Lee; Yao, Jun; Wang, Bin

    2014-01-01

    Summary Germline mutations of BRCA1 confer hereditary susceptibility to breast and ovarian cancer. However, somatic mutation of BRCA1 is infrequent in sporadic breast cancers. The BRCA1 protein C-terminus BRCT domains interact with multiple proteins and are required for BRCA1's tumor suppressor function. In this study, we demonstrated that Abraxas, a BRCA1 BRCT domain-interacting protein, plays a role in tumor suppression. Abraxas exerts its function through binding to BRCA1 to regulate DNA repair and maintain genome stability. Both homozygous and heterozygous Abraxas knockout mice exhibited decreased survival and increased tumor incidence. The gene encoding Abraxas suffers from gene copy loss and somatic mutations in multiple human cancers including breast, ovarian, and endometrial cancers, suggesting that mutation and loss of function of Abraxas may contribute to tumor development in human patients. PMID:25066119

  7. First application of next-generation sequencing in Moroccan breast/ovarian cancer families and report of a novel frameshift mutation of the BRCA1 gene

    PubMed Central

    Jouali, Farah; Laarabi, Fatima-Zahra; Marchoudi, Nabila; Ratbi, Ilham; Elalaoui, Siham Chafai; Rhaissi, Houria; Fekkak, Jamal; Sefiani, Abdelaziz

    2016-01-01

    At present, breast cancer is the most common type of cancer in females. The majority of cases are sporadic, but 5–10% are due to an inherited predisposition to develop breast and ovarian cancers, which are transmitted as an autosomal dominant form with incomplete penetrance. The beneficial effects of clinical genetic testing, including next generation sequencing (NGS) for BRCA1/2 mutations, is major; in particular, it benefits the care of patients and the counseling of relatives that are at risk of breast cancer, in order to reduce breast cancer mortality. BRCA genetic testing was performed in 15 patients with breast cancer and a family with positivity for the heterozygous c.6428C>A mutation of the BRCA2 gene. Informed consent was obtained from all the subjects. Genomic DNAs were extracted and the NGS for genes was performed using the Ion Torrent Personal Genome Machine (PGM) with a 316 chip. The reads were aligned with the human reference HG19 genome to elucidate variants in the BRCA1 and BRCA2 genes. Mutations detected by the PGM platform were confirmed by target direct Sanger sequencing on a second patient DNA sample. In total, 4 BRCA variants were identified in 6 families by NGS. Of these, 3 mutations had been previously reported: c.2126insA of BRCA1, and c.1310_1313delAAGA and c.7235insG of BRCA2. The fourth variant, c.3453delT in BRCA1, has, to the best of our knowledge, never been previously reported. The present study is the first to apply NGS of the BRCA1 and BRCA2 genes to a Moroccan population, prompting additional investigation into local founder mutations and variant characteristics in the region. The variants with no clear clinical significance may present a diagnostic challenge when performing targeted resequencing. These results confirm that an NGS approach based on Ampliseq libraries and PGM sequencing is a highly efficient, speedy and high-throughput mutation detection method, which may be preferable in lower income countries. PMID:27446417

  8. The Leu33Pro polymorphism in the ITGB3 gene does not modify BRCA1/2-associated breast or ovarian cancer risks: results from a multicenter study among 15,542 BRCA1 and BRCA2 mutation carriers

    PubMed Central

    Jakubowska, Anna; Rozkrut, Dominik; Antoniou, Antonis; Hamann, Ute; Lubinski, Jan

    2011-01-01

    Integrins containing the β3 subunit are key players in tumor growth and metastasis. A functional Leu33Pro polymorphism (rs5918) in the β3 subunit of the integrin gene (ITGB3) has previously been suggested to act as a modifier of ovarian cancer risk in Polish BRCA1 mutation carriers. To investigate the association further, we genotyped 9,998 BRCA1 and 5,544 BRCA2 mutation carriers from 34 studies from the Consortium of Investigators of Modifiers of BRCA1/2 for the ITGB3 Leu33Pro polymorphism. Data were analysed within a Cox-proportional hazards framework using a retrospective likelihood approach. There was marginal evidence that the ITGB3 polymorphism was associated with an increased risk of ovarian cancer for BRCA1 mutation carriers (per-allele Hazard Ratio (HR) 1.11, 95% CI 1.00–1.23, p-trend 0.05). However, when the original Polish study was excluded from the analysis, the polymorphism was no longer significantly associated with ovarian cancer risk (HR 1.07, 95% CI 0.96–1.19, p-trend 0.25). There was no evidence of an association with ovarian cancer risk for BRCA2 mutation carriers (HR 1.09, 95% CI 0.89–1.32). The polymorphism was not associated with breast cancer risk for either BRCA1 or BRCA2 mutation carriers. The ITGB3 Leu33Pro polymorphism does not modify breast or ovarian cancer risk in BRCA1 or BRCA2 mutation carriers. PMID:19876733

  9. Recurrent germline mutations in BRCA1 and BRCA2 genes in high risk families in Israel.

    PubMed

    Laitman, Yael; Simeonov, Monica; Herskovitz, Liron; Kushnir, Anya; Shimon-Paluch, Shani; Kaufman, Bella; Zidan, Jamal; Friedman, Eitan

    2012-06-01

    The spectrum of germline mutations among Jewish non Ashkenazi high risk breast/ovarian cancer families includes a few predominant mutations in BRCA1 (185delAG and Tyr978X) and BRCA2 (8765delAG). A few additional recurring mutations [A1708E, 981delAT, C61G (BRCA1) R2336P, and IVS2 + 1G > A (BRCA2)] have been reported in Jewish non Ashkenazi families. The 4153delA*BRCA1 C61G*BRCA1 and the 4075delGT*BRCA2 has been reported to recur in Russian/Polish non Jews and Ashkenazim, respectively. The rate of these recurring mutations has not been reported in Israeli high risk families. Genotyping for these recurring mutations by restriction enzyme digest and sequencing method was applied to high risk, predominantly cancer affected, unrelated Israeli individuals of Ashkenazi (n = 827), non Ashkenazi (n = 2,777), non Jewish Caucasians (n = 193), and 395 of mixed ethnicity. Jewish participants included 827 Ashkenazi, 804 Balkans, 847 North Africans, 234 Yemenites, and 892 Asians (Iraq and Iran). Age at diagnosis of breast cancer (median ± SD) (n = 2,484) was 47.2 ± 9.6 for all women participants. Males (n = 236) were also included, of whom 24 had breast cancer and 35 had pancreatic cancer. Overall, 8/282 (2.8%) of the Balkan cases carried the BRCA1*A1708E mutation, 4/180 (2.2%) the R2336P mutation, and 0/270 the IVS2 + 1G > A BRCA2 mutations, respectively. Of North Africans, 7/264 (2.65%) carried the BRCA1*981delAT mutation. The BRCA1*C61G mutation was detected in 3/269 Ashkenazi, non Ashkenazi, and non Jewish Russians; the BRCA1*Tyr978X mutation was detected in 23/3220 individuals of non Ashkenazi origin, exclusively of Asian ethnicity (23/892, 2.6% of the Asians tested). The BRCA1*4153delA mutation was noted in 2/285 non Jewish Caucasians, and none of the Ashkenazim (n = 500) carried the BRCA2*4075delGT mutation. Jewish high risk families of North African, Asian, and Balkan descent should be screened for the 981delAT, Tyr978X, A1708E BRCA1, and the R2336P BRCA2 mutations

  10. Cell cycle-dependent DNA damage signaling induced by ICRF-193 involves ATM, ATR, CHK2, and BRCA1

    SciTech Connect

    Park, Iha; Avraham, Hava Karsenty . E-mail: havraham@bidmc.harvard.edu

    2006-07-01

    Topoisomerase II is essential for cell proliferation and survival and has been a target of various anticancer drugs. ICRF-193 has long been used as a catalytic inhibitor to study the function of topoisomerase II. Here, we show that ICRF-193 treatment induces DNA damage signaling. Treatment with ICRF-193 induced G2 arrest and DNA damage signaling involving {gamma}-H2AX foci formation and CHK2 phosphorylation. DNA damage by ICRF-193 was further demonstrated by formation of the nuclear foci of 53BP1, NBS1, BRCA1, MDC1, and FANCD2 and increased comet tail moment. The DNA damage signaling induced by ICRF-193 was mediated by ATM and ATR and was restricted to cells in specific cell cycle stages such as S, G2, and mitosis including late and early G1 phases. Downstream signaling of ATM and ATR involved the phosphorylation of CHK2 and BRCA1. Altogether, our results demonstrate that ICRF-193 induces DNA damage signaling in a cell cycle-dependent manner and suggest that topoisomerase II might be essential for the progression of the cell cycle at several stages including DNA decondensation.

  11. In situ hybridization chain reaction mediated ultrasensitive enzyme-free and conjugation-free electrochemcial genosensor for BRCA-1 gene in complex matrices.

    PubMed

    Yang, Hui; Gao, Yang; Wang, Siqi; Qin, You; Xu, Lu; Jin, Dan; Yang, Fan; Zhang, Guo-Jun

    2016-06-15

    In this study, we report an enzyme-free and conjugation-free electrochemical genosensor enabling an ultrasensitive readout of BRCA-1, a breast cancer susceptibility gene. The sensor employs a target-responsive hybridization chain reaction (HCR) to significantly amplify the detectable current signals. By means of a functional auxiliary probe pair and a versatile initiator sequence, a linear DNA concatemer structure can be formed via spontaneous and continuous polymerization of DNA oligomers in the presence of target sequence. Such a DNA nanoassembly endows the genosensor an ultrahigh sensitivity up to 1 aM, which is higher than that of the nanomaterials-based or enzyme mediated amplification approaches by several orders of magnitude. More importantly, the sensor's responsive peak current exhibits a favorable linear correlation to the logarithm of the concentrations of target sequence ranging from 1aM to 10pM. In addition, the sensor is highly selective, and can discriminate a single mismatched sequence. This HCR-based genosensor is also capable of probing low-abundance BRCA-1 gene sequence directly in complex matrices, such as 50% human serum, with minimal interference. These advantages will make our tailor-engineered HCR-based electrochemical genosensor appealing to genetic analysis and clinical diagnostics. PMID:26875018

  12. BRCA1/FANCD2/BRG1-Driven DNA Repair Stabilizes the Differentiation State of Human Mammary Epithelial Cells.

    PubMed

    Wang, Hua; Bierie, Brian; Li, Andrew G; Pathania, Shailja; Toomire, Kimberly; Dimitrov, Stoil D; Liu, Ben; Gelman, Rebecca; Giobbie-Hurder, Anita; Feunteun, Jean; Polyak, Kornelia; Livingston, David M

    2016-07-21

    An abnormal differentiation state is common in BRCA1-deficient mammary epithelial cells, but the underlying mechanism is unclear. Here, we report a convergence between DNA repair and normal, cultured human mammary epithelial (HME) cell differentiation. Surprisingly, depleting BRCA1 or FANCD2 (Fanconi anemia [FA] proteins) or BRG1, a mSWI/SNF subunit, caused HME cells to undergo spontaneous epithelial-to-mesenchymal transition (EMT) and aberrant differentiation. This also occurred when wild-type HMEs were exposed to chemicals that generate DNA interstrand crosslinks (repaired by FA proteins), but not in response to double-strand breaks. Suppressed expression of ΔNP63 also occurred in each of these settings, an effect that links DNA damage to the aberrant differentiation outcome. Taken together with somatic breast cancer genome data, these results point to a breakdown in a BRCA/FA-mSWI/SNF-ΔNP63-mediated DNA repair and differentiation maintenance process in mammary epithelial cells that may contribute to sporadic breast cancer development. PMID:27373334

  13. Ubc9 Mediates Nuclear Localization and Growth Suppression of BRCA1 and BRCA1a Proteins

    PubMed Central

    QIN, YUNLONG; XU, JINGYAO; AYSOLA, KARTIK; BEGUM, NURJAHAN; REDDY, VAISHALI; CHAI, YULI; GRIZZLE, WILLIAM E.; PARTRIDGE, EDWARD E.; REDDY, E. SHYAM P.; RAO, VEENA N.

    2012-01-01

    BRCA1 gene mutations are responsible for hereditary breast and ovarian cancers. In sporadic breast tumors, BRCA1 dysfunction or aberrant subcellular localization is thought to be common. BRCA1 is a nuclear–cytoplasm shuttling protein and the reason for cytoplasmic localization of BRCA1 in young breast cancer patients is not yet known. We have previously reported BRCA1 proteins unlike K109R and cancer-predisposing mutant C61G to bind Ubc9 and modulate ER-α turnover. In the present study, we have examined the consequences of altered Ubc9 binding and knockdown on the subcellular localization and growth inhibitory function of BRCA1 proteins. Our results using live imaging of YFP, GFP, RFP-tagged BRCA1, BRCA1a and BRCA1b proteins show enhanced cytoplasmic localization of K109 R and C61G mutant BRCA1 proteins in normal and cancer cells. Furthermore, down-regulation of Ubc9 in MCF-7 cells using Ubc9 siRNA resulted in enhanced cytoplasmic localization of BRCA1 protein and exclusive cytoplasmic retention of BRCA1a and BRCA1b proteins. These mutant BRCA1 proteins were transforming and impaired in their capacity to inhibit growth of MCF-7 and CAL51 breast cancer cells. Interestingly, cytoplasmic BRCA1a mutants showed more clonogenicity in soft agar and higher levels of expression of Ubc9 than parental MCF7 cells. This is the first report demonstrating the physiological link between cytoplasmic mislocalization of mutant BRCA1 proteins, loss of ER-α repression, loss of ubiquitin ligase activity and loss of growth suppression of BRCA1 proteins. Thus, binding of BRCA1 proteins to nuclear chaperone Ubc9 provides a novel mechanism for nuclear import and control of tumor growth. PMID:21344391

  14. BRCA1 epigenetic inactivation predicts sensitivity to platinum-based chemotherapy in breast and ovarian cancer

    PubMed Central

    Stefansson, Olafur A.; Villanueva, Alberto; Vidal, August; Martí, Lola; Esteller, Manel

    2012-01-01

    Germline mutations in the BRCA1 or BRCA2 genes are associated with an increased risk of breast and ovarian cancer development. Both genes are involved in DNA repair, and tumors harboring genetic defects in them are thought to be more sensitive to DNA-damaging agents used in chemotherapy. However, as only a minority of breast and ovarian cancer patients carry BRCA1 or BRCA2 mutations, few patients are likely to benefit from these pharmacogenetic biomarkers. Herein, we show that, in cancer cell lines and xenografted tumors, BRCA1 CpG island promoter hypermethylation-associated silencing also predicts enhanced sensitivity to platinum-derived drugs to the same extent as BRCA1 mutations. Most importantly, BRCA1 hypermethylation proves to be a predictor of longer time to relapse and improved overall survival in ovarian cancer patients undergoing chemotherapy with cisplatin. PMID:23069641

  15. BRCA1 polymorphism in breast cancer patients from Argentina

    PubMed Central

    JAURE, OMAR; ALONSO, ELIANA N.; BRAICO, DIEGO AGUILERA; NIETO, ALVARO; OROZCO, MANUELA; MORELLI, CECILIA; FERRO, ALEJANDRO M.; BARUTTA, ELENA; VINCENT, ESTEBAN; MARTÍNEZ, DOMINGO; MARTÍNEZ, IGNACIO; MAEGLI, MARIA INES; FRIZZA, ALEJANDRO; KOWALYZYN, RUBEN; SALVADORI, MARISA; GINESTET, PAUL; GONZALEZ DONNA, MARIA L.; BALOGH, GABRIELA A.

    2015-01-01

    Breast cancer is the most common type of cancer in females in Argentina, with an incidence rate similar to that in the USA. However, the contribution of the BRCA1 or BRCA2 mutation in breast cancer incidence has not yet been investigated in Argentina. In order to evaluate which BRCA1 polymorphisms or mutations characterize female breast cancer in Argentina, the current study enrolled 206 females with breast cancer from several hospitals from the southeast of Argentina. A buccal smear sample was obtained in duplicate from each patient and the DNA samples were processed for polymorphism analysis using the single-strand conformational polymorphism technique. The polymorphisms in BRCA1 were investigated using a combination of 15 primers to analyze exons 2, 3, 5, 20 and 11 (including the 11.1 to 11.12 regions). The BRCA1 mutations were confirmed by direct sequencing. Samples were successfully examined from 154 females and, among these, 16 mutations were identified in the BRCA1 gene representing 13.9% of the samples analyzed. One patient was identified with a polymorphism in exon 2 (0.86%), four in exon 20 (3.48%), four in exon 11.3 (3.48%), one in exon 11.7 (0.86%), two in exon 11.8 (1.74%), one in exon 11.10 (0.86%) and one in exon 11.11 (0.86%). The most prevalent alteration in BRCA1 was located in exon 11 (11 out of 16 patients; 68.75%). The objective of our next study is to evaluate the prevalence of mutations in the BRCA2 gene and analyze the BRCA1 gene in the healthy relatives of BRCA1 mutation carriers. PMID:25624909

  16. RNF4-dependent hybrid SUMO-ubiquitin chains are signals for RAP80 and thereby mediate the recruitment of BRCA1 to sites of DNA damage.

    PubMed

    Guzzo, Catherine M; Berndsen, Christopher E; Zhu, Jianmei; Gupta, Vibhor; Datta, Ajit; Greenberg, Roger A; Wolberger, Cynthia; Matunis, Michael J

    2012-12-01

    The DNA repair function of the breast cancer susceptibility protein BRCA1 depends in part on its interaction with RAP80, which targets BRCA1 to DNA double-strand breaks (DSBs) through recognition of K63-linked polyubiquitin chains. The localization of BRCA1 to DSBs also requires sumoylation. We demonstrated that, in addition to having ubiquitin-interacting motifs, RAP80 also contains a SUMO-interacting motif (SIM) that is critical for recruitment to DSBs. In combination with the ubiquitin-binding activity of RAP80, this SIM enabled RAP80 to bind with nanomolar affinity to hybrid chains consisting of ubiquitin conjugated to SUMO. Furthermore, RNF4, a SUMO-targeted ubiquitin E3 ligase that synthesizes hybrid SUMO-ubiquitin chains, localized to DSBs and was critical for the recruitment of RAP80 and BRCA1 to sites of DNA damage. Our findings, therefore, connect ubiquitin- and SUMO-dependent DSB recognition, revealing that RNF4-synthesized hybrid SUMO-ubiquitin chains are recognized by RAP80 to promote BRCA1 recruitment and DNA repair. PMID:23211528

  17. Detection of BRCA1 and BRCA2 gene mutation in Egyptian females with breast cancer and their relatives by PCR-SSCP method.

    PubMed

    Fattouh, Mona; Ahmed, Hydi; Hafez, Elsayed El-Sayed

    2011-01-01

    Germline mutations in the BRCA1 or BRCA2 genes predispose their carriers to breast or/and ovarian cancers during their lifetime. This study was performed to identify germline mutations in BRCA1 and BRCA2 genes for the early detection of pre-symptomatic mutation carriers in Egyptian healthy females who were first-degree relatives of affected women from families with and without family history of breast cancer. Sixty-two patients (index cases) with invasive breast cancer belonging to sixty families and their asymptomatic female first-degree relatives (300 cases) were studied for germline mutations of BRCA1 and BRCA2 genes. Five mutations were detected in 52 families (86.7%) with inherited mutations in either BRCA1 or BRCA2. Sixty percent of these families had BRCA1 mutation and 26.7% had BRCA2 mutations. They were identified by using the combination of SSCP and heteroduplex analysis. All but one of the mutations were detected within the BRCA1 gene in addition to one mutation in the BRCA2 gene. PMID:23082475

  18. Screening of the BRCA1 gene in Brazilian patients with breast and/or ovarian cancer via high-resolution melting reaction analysis.

    PubMed

    de Oliveira, Eneida Santos; Soares, Bárbara Luisa; Lemos, Sara; Rosa, Reginaldo Cruz Alves; Rodrigues, Angélica Nogueira; Barbosa, Leandro Augusto; de Oliveira Lopes, Débora; dos Santos, Luciana Lara

    2016-04-01

    The aim of this study was to evaluate the profile of BRCA1 mutations among cancer-affected Brazilian women from the Midwest region of Minas Gerais state with clearly defined risk factors for hereditary breast and ovarian cancer (HBOC) syndrome. In this Brazilian region, the first Center for Hereditary Cancer Control began operation in 2011, and 90% of patients receive assistance from the public health service. Eighteen patients at high risk for HBOC were subjected to molecular analysis. Primers were designed for 22 coding exons of the gene; DNA was extracted; and real-time PCR followed by high-resolution melting reaction was performed. The amplicons were sequenced to confirm the identified profiles. Only exon 11 was directly sequenced due its length. Multiplex ligation-dependent probe amplification (MLPA) was performed for those patients in whom no pathogenic mutations were found. Among the 14 alterations identified in this study, the c.5263_5264insC pathogenic mutation was present in two patients (11.1%). Four alterations showed no clinical relevance; one exhibited inconclusive clinical relevance according to the examined databases; and eight alterations presented a divergent classification between the databases. No deletions or duplications were found using the MLPA technique. The HRM methodology was highly sensitive in identifying variants in the BRCA1 gene and can dramatically reduce the amount of sequencing required to identify germline mutations in BRCA genes, enabling cheaper tests and increasing their availability to Brazilian women assisted by the public health service. PMID:26666763

  19. Localization of BRCA1 protein in breast cancer tissue and cell lines with mutations

    PubMed Central

    2013-01-01

    Background The breast and ovarian cancer susceptibility gene (BRCA1) encodes a tumor suppressor. The BRCA1 protein is found primarily in cell nuclei and plays an important role in the DNA damage response and transcriptional regulation. Deficiencies in DNA repair capabilities have been associated with higher histopathological grade and worse prognosis in breast cancer. Methods In order to investigate the subcellular distribution of BRCA1 in tumor tissue we randomly selected 22 breast carcinomas and tested BRCA1 protein localization in frozen and contiguous formalin-fixed, paraffin embedded (FFPE) tissue, using pressure cooker antigen-retrieval and the MS110 antibody staining. To assess the impact of BRCA1 germline mutations on protein localization, we retrospectively tested 16 of the tumor specimens to determine whether they contained the common Ashkenazi Jewish founder mutations in BRCA1 (185delAG, 5382insC), and BRCA2 (6174delT). We also compared co-localization of BRCA1 and nucleolin in MCF7 cells (wild type) and a mutant BRCA1 cell line, HCC1937 (5382insC). Results In FFPE tissue, with MS110 antibody staining, we frequently found reduced BRCA1 nuclear staining in breast tumor tissue compared to normal tissue, and less BRCA1 staining with higher histological grade in the tumors. However, in the frozen sections, BRCA1 antibody staining showed punctate, intra-nuclear granules in varying numbers of tumor, lactating, and normal cells. Two mutation carriers were identified and were confirmed by gene sequencing. We have also compared co-localization of BRCA1 and nucleolin in MCF7 cells (wild type) and a mutant BRCA1 cell line, HCC1937 (5382insC) and found altered sub-nuclear and nucleolar localization patterns consistent with a functional impact of the mutation on protein localization. Conclusions The data presented here support a role for BRCA1 in the pathogenesis of sporadic and inherited breast cancers. The use of well-characterized reagents may lead to further

  20. Photocatalytic electrosensor for label-free and ultrasensitive detection of BRCA1 gene.

    PubMed

    Qin, Xiaojiao; Xu, Shuxia; Deng, Li; Huang, Rongfu; Zhang, Xinfeng

    2016-11-15

    In this work, we have developed an electrochemical sensor for label-free and ultrasensitive detection of DNA (exemplified by breast cancer 1 gene) by using a photocatalytic reaction. Upon recognition of target DNA, the ethidium bromide molecules which were embedded in the hybridized double strand DNA (dsDNA, target DNA and capture DNA) could photo-catalytically generate singlet oxygen upon green light emitting diode irradiation, leading to an efficient cleave of the dsDNA. As a result, the voltammetry for the [Fe(CN)6](3-/4-) was improved remarkably because of less blocking of electrode and weaker charge repulsion. Such a simple strategy provided an ultrasensitive detection of breast cancer 1 gene down to the attomolar level with a broad linear range (10 aM-100 nM). The sensor is by far the most sensitive electrochemical method for detection of breast cancer 1 gene without an amplification procedure. Also the sensor can discriminate mismatched DNA from perfectly matched target DNA with high selectivity. Therefore, simplicity, high sensitivity and specificity provided by this photocatalytic eletrosensor will make it a promising tool for early diagnosis of gene-related diseases. PMID:27317999

  1. A whole-genome massively parallel sequencing analysis of BRCA1 mutant oestrogen receptor negative and positive breast cancers

    PubMed Central

    Weigelt, Britta; Wilkerson, Paul M; Manie, Elodie; Grigoriadis, Anita; A’Hern, Roger; van der Groep, Petra; Kozarewa, Iwanka; Popova, Tatiana; Mariani, Odette; Turaljic, Samra; Furney, Simon J; Marais, Richard; Rodruigues, Daniel-Nava; Flora, Adriana C; Wai, Patty; Pawar, Vidya; McDade, Simon; Carroll, Jason; Stoppa-Lyonnet, Dominique; Green, Andrew R; Ellis, Ian O; Swanton, Charles; van Diest, Paul; Delattre, Olivier; Lord, Christopher J; Foulkes, William D; Vincent-Salomon, Anne; Ashworth, Alan; Stern, Marc Henri; Reis-Filho, Jorge S

    2016-01-01

    BRCA1 encodes a tumour suppressor protein that plays pivotal roles in homologous recombination (HR) DNA repair, cell-cycle checkpoints, and transcriptional regulation. BRCA1 germline mutations confer a high risk of early-onset breast and ovarian cancer. In >80% of cases, tumours arising in BRCA1 germline mutation carriers are oestrogen receptor (ER)-negative, however up to 15% are ER-positive. It has been suggested that BRCA1 ER-positive breast cancers constitute sporadic cancers arising in the context of a BRCA1 germline mutation rather than being causally related to BRCA1 loss-of-function. Whole-genome massively parallel sequencing of ER-positive and ER-negative BRCA1 breast cancers, and their respective germline DNAs, was used to characterise the genetic landscape of BRCA1 cancers at base-pair resolution. Only BRCA1 germline mutations and somatic loss of the wild-type allele, and TP53 somatic mutations were recurrently found in the index cases. BRCA1 breast cancers displayed a mutational signature consistent with that caused by lack of HR DNA repair in both ER-positive and ER-negative cases. Sequencing analysis of independent cohorts of hereditary BRCA1 and sporadic non-BRCA1 breast cancers for the presence of recurrent pathogenic mutations and/or homozygous deletions found in the index cases revealed that DAPK3, TMEM135, KIAA1797, PDE4D and GATA4 are potential additional drivers of breast cancers. This study demonstrates that BRCA1 pathogenic germline mutations coupled with somatic loss of the wild-type allele are not sufficient for hereditary breast cancers to display an ER-negative phenotype, and has led to the identification of three potential novel breast cancer genes (i.e. DAPK3, TMEM135 and GATA4). PMID:22362584

  2. BRCA1 Mutation: A Predictive Marker for Radiation Therapy?

    PubMed

    Kan, Charlene; Zhang, Junran

    2015-10-01

    DNA repair, in particular, DNA double-strand break (DSB) repair, is essential for the survival of both normal and cancer cells. An elaborate repair mechanism has been developed in cells to efficiently repair the damaged DNA. The pathways predominately involved in DSB repair are homologous recombination and classic nonhomologous end-joining, although the alternative NHEJ pathway, a third DSB repair pathway, could also be important in certain contexts. The protein of BRCA1 encoded by the tumor suppressor gene BRCA1 regulates all DSB repair pathways. Given that DSBs represent the most biologically significant lesions induced by ionizing radiation and that impaired DSB repair leads to radiation sensitivity, it has been expected that cancer patients with BRCA1 mutations should benefit from radiation therapy. However, the clinical data have been conflicting and inconclusive. We provide an overview about the current status of the data regarding BRCA1 deficiency and radiation therapy sensitivity in both experimental models and clinical investigations. In addition, we discuss a strategy to potentiate the effects of radiation therapy by poly(ADP-ribose) polymerase inhibitors, the pharmacologic drugs being investigated as monotherapy for the treatment of patients with BRCA1/2 mutations. PMID:26383678

  3. BRCA1 Mutation: A Predictive Marker for Radiation Therapy?

    SciTech Connect

    Kan, Charlene; Zhang, Junran

    2015-10-01

    DNA repair, in particular, DNA double-strand break (DSB) repair, is essential for the survival of both normal and cancer cells. An elaborate repair mechanism has been developed in cells to efficiently repair the damaged DNA. The pathways predominately involved in DSB repair are homologous recombination and classic nonhomologous end-joining, although the alternative NHEJ pathway, a third DSB repair pathway, could also be important in certain contexts. The protein of BRCA1 encoded by the tumor suppressor gene BRCA1 regulates all DSB repair pathways. Given that DSBs represent the most biologically significant lesions induced by ionizing radiation and that impaired DSB repair leads to radiation sensitivity, it has been expected that cancer patients with BRCA1 mutations should benefit from radiation therapy. However, the clinical data have been conflicting and inconclusive. We provide an overview about the current status of the data regarding BRCA1 deficiency and radiation therapy sensitivity in both experimental models and clinical investigations. In addition, we discuss a strategy to potentiate the effects of radiation therapy by poly(ADP-ribose) polymerase inhibitors, the pharmacologic drugs being investigated as monotherapy for the treatment of patients with BRCA1/2 mutations.

  4. Characterization of a novel large deletion and single point mutations in the BRCA1 gene in a Greek cohort of families with suspected hereditary breast cancer

    PubMed Central

    Belogianni, Ioulia; Apessos, Angela; Mihalatos, Markos; Razi, Evangelia; Labropoulos, Stefanos; Petounis, Andreas; Gaki, Vasiliki; Keramopoulos, Antonios; Pandis, Nikos; Kyriacou, Kyriacos; Hadjisavvas, Andreas; Kosmidis, Paris; Yannoukakos, Drakoulis; Nasioulas, Georgios

    2004-01-01

    Background Germline mutations in BRCA1 and BRCA2 predispose to breast and ovarian cancer. A multitude of mutations have been described and are found to be scattered throughout these two large genes. We describe analysis of BRCA1 in 25 individuals from 18 families from a Greek cohort. Methods The approach used is based on dHPLC mutation screening of the BRCA1 gene, followed by sequencing of fragments suspected to carry a mutation including intron – exon boundaries. In patients with a strong family history but for whom no mutations were detected, analysis was extended to exons 10 and 11 of the BRCA2 gene, followed by MLPA analysis for screening for large genomic rearrangements. Results A pathogenic mutation in BRCA1 was identified in 5/18 (27.7 %) families, where four distinct mutations have been observed. Single base putative pathogenic mutations were identified by dHPLC and confirmed by sequence analysis in 4 families: 5382insC (in two families), G1738R, and 5586G > A (in one family each). In addition, 18 unclassified variants and silent polymorphisms were detected including a novel silent polymorphism in exon 11 of the BRCA1 gene. Finally, MLPA revealed deletion of exon 20 of the BRCA1 gene in one family, a deletion that encompasses 3.2 kb of the gene starting 21 bases into exon 20 and extending 3.2 kb into intron 20 and leads to skipping of the entire exon 20. The 3' breakpoint lies within an AluSp repeat but there are no recognizable repeat motifs at the 5' breakpoint implicating a mechanism different to Alu-mediated recombination, responsible for the majority of rearrangements in the BRCA1 gene. Conclusions We conclude that a combination of techniques capable of detecting both single base mutations and small insertions / deletions and large genomic rearrangements is necessary in order to accurately analyze the BRCA1 gene in patients at high risk of carrying a germline mutation as determined by their family history. Furthermore, our results suggest that in

  5. Interpersonal Responses Among Sibling Dyads Tested for BRCA1/BRCA2 Gene Mutations

    PubMed Central

    Hamann, Heidi A.; Croyle, Robert T.; Smith, Timothy W.; Smith, Ken R.; Ruiz, John M.; Kircher, John C.; Botkin, Jeffrey R.

    2013-01-01

    Objective The familial context plays an important role in psychosocial responses to genetic testing. The purpose of this study was to compare sibling pairs with different combinations of BRCA1/BRCA2 test results on measures of affect, interpersonal responses, and physiological reactions. Design Forty-nine sibling dyads with different combinations of BRCA1/BRCA2 test results (i.e., mixed, positive, negative) completed a questionnaire, and 35 of the dyads also participated in a laboratory-based discussion of genetic testing. Main Outcome Measures The primary outcome variables included participant reports of supportive actions toward their sibling, state anger and anxiety, perceptions of sibling behavior, and electrodermal responses. Results Compared to positive and negative dyads, mixed pairs reported less friendly general support actions, noted more anger, and perceived their sibling to be less friendly and more dominant during the interactions. In comparisons between same-result (i.e., positive, negative) pairs, positive dyads reported more dominant support behaviors and perceived their sibling to be friendlier during the interactions. Conclusion Data suggest that siblings who have different test results may experience more interpersonal strain than siblings who have the same test result. Future research on genetic testing and family relationships can expand upon these findings. PMID:18230020

  6. BRCA1-directed, enhanced and aberrant homologous recombination

    PubMed Central

    Dever, Seth M; White, E Railey; Hartman, Matthew CT

    2012-01-01

    Despite intense studies, questions still remain regarding the molecular mechanisms leading to the development of hereditary breast and ovarian cancers. Research focused on elucidating the role of the breast cancer susceptibility gene 1 (BRCA1) in the DNA damage response may be of the most critical importance to understanding these processes. The BRCA1 protein has an N-terminal RING domain possessing E3 ubiquitin-ligase activity and a C-terminal BRCT domain involved in binding specific phosphoproteins. These domains are involved directly or indirectly in DNA double-strand break (DSB) repair. As the two terminal domains of BRCA1 represent two separate entities, understanding how these domains communicate and are functionally altered in regards to DSB repair is critical for understanding the development of BRCA1-related breast and ovarian cancers and for developing novel therapeutics. Herein, we review recent findings of how altered functions of these domains might lead to cancer through a mechanism of increased aberrant homologous recombination and possible implications for the development of BRCA1 inhibitors. PMID:22306997

  7. 53BP1, BRCA1, and the Choice between Recombination and End Joining at DNA Double-Strand Breaks

    PubMed Central

    Sung, Patrick

    2014-01-01

    When DNA double-strand breaks occur, the cell cycle stage has a major influence on the choice of the repair pathway employed. Specifically, nonhomologous end joining is the predominant mechanism used in the G1 phase of the cell cycle, while homologous recombination becomes fully activated in S phase. Studies over the past 2 decades have revealed that the aberrant joining of replication-associated breaks leads to catastrophic genome rearrangements, revealing an important role of DNA break repair pathway choice in the preservation of genome integrity. 53BP1, first identified as a DNA damage checkpoint protein, and BRCA1, a well-known breast cancer tumor suppressor, are at the center of this choice. Research on how these proteins function at the DNA break site has advanced rapidly in the recent past. Here, we review what is known regarding how the repair pathway choice is made, including the mechanisms that govern the recruitment of each critical factor, and how the cell transitions from end joining in G1 to homologous recombination in S/G2. PMID:24469398

  8. The Exon 13 Duplication in the BRCA1 Gene Is a Founder Mutation Present in Geographically Diverse Populations

    PubMed Central

    2000-01-01

    Recently, a 6-kb duplication of exon 13, which creates a frameshift in the coding sequence of the BRCA1 gene, has been described in three unrelated U.S. families of European ancestry and in one Portuguese family. Here, our goal was to estimate the frequency and geographic diversity of carriers of this duplication. To do this, a collaborative screening study was set up that involved 39 institutions from 19 countries and included 3,580 unrelated individuals with a family history of the disease and 934 early-onset breast and/or ovarian cancer cases. A total of 11 additional families carrying this mutation were identified in Australia (1), Belgium (1), Canada (1), Great Britain (6), and the United States (2). Haplotyping showed that they are likely to derive from a common ancestor, possibly of northern British origin. Our results demonstrate that it is strongly advisable, for laboratories carrying out screening either in English-speaking countries or in countries with historical links with Britain, to include within their BRCA1 screening protocols the polymerase chain reaction–based assay described in this report. PMID:10827109

  9. p53 suppresses hyper-recombination by modulating BRCA1 function

    PubMed Central

    Dong, Chao; Zhang, Fengmei; Luo, Yue; Wang, Hui; Zhao, Xipeng; Guo, Gongshe; Powell, Simon N.; Feng, Zhihui

    2015-01-01

    Both p53 and BRCA1 are tumor suppressors and are involved in a number of cellular processes including cell cycle arrest, apoptosis, transcriptional regulation, and DNA damage repair. Some studies have suggested that the association of BRCA1 and p53 is required for transcriptional regulation of genes involved in cell replication and DNA repair pathways. However, the relationship between the two proteins in molecular mechanisms of DNA repair is still not clear. Therefore, we sought to determine whether there is a functional link between p53 and BRCA1 in DNA repair. Firstly, using a plasmid recombination substrate, pDR-GFP, integrated into the genome of breast cancer cell line MCF7, we have demonstrated that p53 suppressed Rad51-mediated hyper-recombinational repair by two independent cell models of HPV-E6 induced p53 inactivation and p53 knockdown assay. Our study further indicated that p53 mediated homologous recombination (HR) through inhibiting BRCA1 over-function via mechanism of transcription regulation in response to DNA repair. Since it was found p53 and BRCA1 existed in a protein complex, indicating both proteins may be associated at post-transcriptional level. Moreover, defective p53-induced hyper-recombination was associated with cell radioresistance and chromosomal stability, strongly supporting the involvement of p53 in the inhibition of hyper-recombination, which led to genetic stability and cellular function in response to DNA damage. In addition, it was found that p53 loss rescued BRCA1 deficiency via recovering HR and chromosomal stability, suggesting that p53 is also involved in the HR-inhibition independently of BRCA1. Thus, our data indicated that p53 was involved in inhibiting recombination by both BRCA1-dependent and -independent mechanisms, and there is a functional link between p53-suppression and BRCA1-promotion in regulation of HR activity at transcription level and possible post-transcription level. PMID:26162908

  10. The rs2910164:G>C SNP in the MIR146A gene is not associated with breast cancer risk in BRCA1 and BRCA2 mutation carriers.

    PubMed

    Garcia, Amandine I; Cox, David G; Barjhoux, Laure; Verny-Pierre, Carole; Barnes, Daniel; Antoniou, Antonis C; Stoppa-Lyonnet, Dominique; Sinilnikova, Olga M; Mazoyer, Sylvie

    2011-09-01

    The rs2910164:G>C SNP is located in the gene for miR-146a, a microRNA that binds the 3' UTR of the BRCA1 transcript. Preliminary data based on the analysis of a small number of cases suggested that this single nucleotide polymorphism (SNP) might be associated with the age of onset of familial breast and ovarian cancer. This effect was not confirmed on a large series of familial breast cancer cases negative for a BRCA1 or BRCA2 mutation. We show here a lack of association of the rs2910164:G>C SNP with breast cancer risk in a series of 1,166 BRCA1 and 560 BRCA2 mutation carriers. In conclusion, the polymorphism in the miR-146a gene is unlikely to be of substantial significance regarding breast cancer risk. PMID:21591024

  11. RANK ligand as a potential target for breast cancer prevention in BRCA1-mutation carriers.

    PubMed

    Nolan, Emma; Vaillant, François; Branstetter, Daniel; Pal, Bhupinder; Giner, Göknur; Whitehead, Lachlan; Lok, Sheau W; Mann, Gregory B; Rohrbach, Kathy; Huang, Li-Ya; Soriano, Rosalia; Smyth, Gordon K; Dougall, William C; Visvader, Jane E; Lindeman, Geoffrey J

    2016-08-01

    Individuals who have mutations in the breast-cancer-susceptibility gene BRCA1 (hereafter referred to as BRCA1-mutation carriers) frequently undergo prophylactic mastectomy to minimize their risk of breast cancer. The identification of an effective prevention therapy therefore remains a 'holy grail' for the field. Precancerous BRCA1(mut/+) tissue harbors an aberrant population of luminal progenitor cells, and deregulated progesterone signaling has been implicated in BRCA1-associated oncogenesis. Coupled with the findings that tumor necrosis factor superfamily member 11 (TNFSF11; also known as RANKL) is a key paracrine effector of progesterone signaling and that RANKL and its receptor TNFRSF11A (also known as RANK) contribute to mammary tumorigenesis, we investigated a role for this pathway in the pre-neoplastic phase of BRCA1-mutation carriers. We identified two subsets of luminal progenitors (RANK(+) and RANK(-)) in histologically normal tissue of BRCA1-mutation carriers and showed that RANK(+) cells are highly proliferative, have grossly aberrant DNA repair and bear a molecular signature similar to that of basal-like breast cancer. These data suggest that RANK(+) and not RANK(-) progenitors are a key target population in these women. Inhibition of RANKL signaling by treatment with denosumab in three-dimensional breast organoids derived from pre-neoplastic BRCA1(mut/+) tissue attenuated progesterone-induced proliferation. Notably, proliferation was markedly reduced in breast biopsies from BRCA1-mutation carriers who were treated with denosumab. Furthermore, inhibition of RANKL in a Brca1-deficient mouse model substantially curtailed mammary tumorigenesis. Taken together, these findings identify a targetable pathway in a putative cell-of-origin population in BRCA1-mutation carriers and implicate RANKL blockade as a promising strategy in the prevention of breast cancer. PMID:27322743

  12. Loss of INPP4B causes a DNA repair defect through loss of BRCA1, ATM and ATR and can be targeted with PARP inhibitor treatment.

    PubMed

    Ip, Laura R H; Poulogiannis, George; Viciano, Felipe Cia; Sasaki, Junko; Kofuji, Satoshi; Spanswick, Victoria J; Hochhauser, Daniel; Hartley, John A; Sasaki, Takehiko; Gewinner, Christina A

    2015-04-30

    Treatment options for ovarian cancer patients remain limited and overall survival is less than 50% despite recent clinical advances. The lipid phosphatase inositol polyphosphate 4-phosphatase type II (INPP4B) has been described as a tumor suppressor in the PI3K/Akt pathway with loss of expression found most pronounced in breast, ovarian cancer and melanoma. Using microarray technology we identified a DNA repair defect in INPP4B-deficient cells, which we further characterized by comet assays and quantification of γH2AX, RAD51 and 53BP1 foci formation. INPP4B loss resulted in significantly increased sensitivity towards PARP inhibition, comparable to loss of BRCA1 in two- and three-dimensional in vitro models, as well as in in vivo xenograft models. Mechanistically, we discovered that INPP4B forms a protein complex with the key players of DNA repair, ATR and BRCA1, in GST pulldown and 293T overexpression assays, and INPP4B loss affects BRCA1, ATM and ATR protein stability resulting in the observed DNA repair defect. Given that INPP4B loss has been found in 40% of ovarian cancer patients, this study provides the rationale for establishing INPP4B as a biomarker of PARP inhibitor response, and consequently offers novel therapeutic options for a significant subset of patients. Loss of the tumor suppressor inositol polyphosphate 4-phosphatase type II (INPP4B) results in a DNA repair defect due to concomitant loss of BRCA1, ATR and ATM and can be therapeutically targeted with PARP inhibitors. PMID:25868852

  13. BRCA1 Regulates IFI16 Mediated Nuclear Innate Sensing of Herpes Viral DNA and Subsequent Induction of the Innate Inflammasome and Interferon-β Responses

    PubMed Central

    Veettil, Mohanan Valiya; Roy, Arunava; Ansari, Mairaj Ahmed; Iqbal, Jawed; Chikoti, Leela; Kumar, Binod; Johnson, Karen E.; Chandran, Bala

    2015-01-01

    The innate immune system pattern recognition receptors (PRR) are the first line of host defenses recognizing the various pathogen- or danger-associated molecular patterns and eliciting defenses by regulating the production of pro-inflammatory cytokines such as IL-1β, IL-18 or interferon β (IFN-β). NOD-like receptors (NLRs) and AIM2-like receptors (ALRs) are cytoplasmic inflammasome sensors of foreign molecules, including DNA. IFI16, a sequence-independent nuclear innate sensor ALR, recognizes episomal dsDNA genomes of herpes viruses such as KSHV, EBV, and HSV-1 in the infected cell nuclei, forms an inflammasome complex with ASC and procaspase1, and relocates into the cytoplasm leading into Caspase-1 and IL-1β generation. IFI16 also induces IFN-β during HSV-1 infection via the cytoplasmic STING-TBK1-IRF3 pathway. Thus far, whether IFI16 recognizes foreign DNA directly or utilizes other host protein(s) is unknown. Here, we demonstrate that BRCA1, a DNA damage repair sensor and transcription regulator, is in complex with IFI16 in the host cell nucleus, and their association increases in the presence of nuclear viral genomes during de novo KSHV, EBV and HSV-1 infection, and in latent KSHV or EBV infection, but not by DNA damage responses (DDR) induced by bleomycin and vaccinia virus cytoplasmic dsDNA. BRCA1 is a constituent of the triggered IFI16-inflammasome and is translocated into the cytoplasm after genome recognition along with the IFI16-inflammasome. The absence of BRCA1 abrogated IFI16-viral genome association, inflammasome assembly, IFI16 cytoplasmic localization, and Caspase-1 and IL-1β production. The absence of BRCA1 also abolished the cytoplasmic IFI16-STING interaction, downstream IRF3 phosphorylation, nuclear translocation of pIRF3 and IFN-β production during de novo KSHV and HSV-1 infection. These findings highlight that BRCA1 plays a hitherto unidentified innate immunomodulatory role by facilitating nuclear foreign DNA sensing by IFI16

  14. LKB1 preserves genome integrity by stimulating BRCA1 expression

    PubMed Central

    Gupta, Romi; Liu, Alex. Y.; Glazer, Peter M.; Wajapeyee, Narendra

    2015-01-01

    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. PMID:25488815

  15. Relationship between three novel SNPs of BRCA1 and canine mammary tumors

    PubMed Central

    SUN, Weidong; YANG, Xu; QIU, Hengbin; ZHANG, Di; WANG, Huanan; HUANG, Jian; LIN, Degui

    2015-01-01

    The BRCA1 gene plays an important role in the development of human breast cancer, and recent research indicated that genetic variations of BRCA1 are also related to canine mammary tumors (CMTs). Here, using rapid amplification of cDNA ends (RACE), we cloned the 5′- and 3′-UTRs of BRCA1. By direct sequencing of the flanking sequences of the 5′- and 3′-UTRs of BRCA1, three previously unreported single-nucleotide polymorphisms (SNPs) were identified, two (−1228T >C, −1173C >T) in the putative promoter regions and one non-synonymous SNP (63449G >A) in exon 23. Compared with 16 normal samples, the sequences from 34 CMTs suggested that SNP (−1173C >T) was associated with the development of CMTs (odds ratio (OR)=2.57, 95% confidence interval (CI): 1.07–6.15). PMID:26156012

  16. Critical role for BRCA1 expression as a marker of chemosensitivity response and prognosis.

    PubMed

    De Luca, Paola; De Siervi, Adriana

    2016-01-01

    Chemotherapy is still the leader option for cancer treatment. Nevertheless some patients develop chemotherapy resistance. One major research goal is to identify the critical genes involved in chemotherapy response to predict the best therapy option for patients. Germline mutations in the BReast Cancer susceptibility gene (BRCA1) are associated to increased risk of developing breast, ovarian and other types of cancers. However, due to harmful BRCA1 gene mutations are relatively rare in the general population, nowadays most researchers focused on BRCA1 expression downregulation and/or epigenetic inactivation in sporadic tumors as a prognosis tool for chemotherapy response in patients. Chemotherapy response can be dramatically different depending on BRCA1 expression status, tumor type and drug. Hence, the chemotherapy response could be dissimilar in breast, ovarian, uterine, prostate, esophageal, gastric and lung cancers. Additionally, differential BRCA1 expression in sporadic tumors shows different response to DNA-damaging agents, mitotic inhibitors or PARP inhibitors. In this review we will examine the response to different chemotherapy agents in several cancer types depending on BRCA1 expression status. PMID:26709647

  17. Targeted sequencing of BRCA1 and BRCA2 across a large unselected breast cancer cohort suggests that one-third of mutations are somatic

    PubMed Central

    Winter, C.; Nilsson, M. P.; Olsson, E.; George, A. M.; Chen, Y.; Kvist, A.; Törngren, T.; Vallon-Christersson, J.; Hegardt, C.; Häkkinen, J.; Jönsson, G.; Grabau, D.; Malmberg, M.; Kristoffersson, U.; Rehn, M.; Gruvberger-Saal, S. K.; Larsson, C.; Borg, Å.; Loman, N.; Saal, L. H.

    2016-01-01

    Background A mutation found in the BRCA1 or BRCA2 gene of a breast tumor could be either germline or somatically acquired. The prevalence of somatic BRCA1/2 mutations and the ratio between somatic and germline BRCA1/2 mutations in unselected breast cancer patients are currently unclear. Patients and methods Paired normal and tumor DNA was analyzed for BRCA1/2 mutations by massively parallel sequencing in an unselected cohort of 273 breast cancer patients from south Sweden. Results Deleterious germline mutations in BRCA1 (n = 10) or BRCA2 (n = 10) were detected in 20 patients (7%). Deleterious somatic mutations in BRCA1 (n = 4) or BRCA2 (n = 5) were detected in 9 patients (3%). Accordingly, about 1 in 9 breast carcinomas (11%) in our cohort harbor a BRCA1/2 mutation. For each gene, the tumor phenotypes were very similar regardless of the mutation being germline or somatically acquired, whereas the tumor phenotypes differed significantly between wild-type and mutated cases. For age at diagnosis, the patients with somatic BRCA1/2 mutations resembled the wild-type patients (median age at diagnosis, germline BRCA1: 41.5 years; germline BRCA2: 49.5 years; somatic BRCA1/2: 65 years; wild-type BRCA1/2: 62.5 years). Conclusions In a population without strong germline founder mutations, the likelihood of a BRCA1/2 mutation found in a breast carcinoma being somatic was ∼1/3 and germline 2/3. This may have implications for treatment and genetic counseling. PMID:27194814

  18. The BRCA1 Breast Cancer Suppressor: Regulation of Transport, Dynamics, and Function at Multiple Subcellular Locations

    PubMed Central

    Henderson, Beric R.

    2012-01-01

    Inherited mutations in the BRCA1 gene predispose to a higher risk of breast/ovarian cancer. The BRCA1 tumor suppressor is a 1863 amino acid protein with multiple protein interaction domains that facilitate its roles in regulating DNA repair and maintenance, cell cycle progression, transcription, and cell survival/apoptosis. BRCA1 was first identified as a nuclear phosphoprotein, but has since been shown to contain different transport sequences including nuclear export and nuclear localization signals that enable it to shuttle between specific sites within the nucleus and cytoplasm, including DNA repair foci, centrosomes, and mitochondria. BRCA1 nuclear transport and ubiquitin E3 ligase enzymatic activity are tightly regulated by the BRCA1 dimeric binding partner BARD1 and further modulated by cancer mutations and diverse signaling pathways. This paper will focus on the transport, dynamics, and multiple intracellular destinations of BRCA1 with emphasis on how regulation of these events has impact on, and determines, a broad range of important cellular functions. PMID:24278741

  19. A role of BRCA1 and BRCA2 germline mutations in breast cancer susceptibility within Sardinian population

    PubMed Central

    2009-01-01

    Background In recent years, numerous studies have assessed the prevalence of germline mutations in BRCA1 and BRCA2 genes in various cohorts. We here extensively investigated the prevalence and geographical distribution of BRCA1-2 mutations in the entire genetically-homogeneous Sardinian population. The occurrence of phenotypic characteristics which may be predictive for the presence of BRCA1-2 germline mutations was also evaluated. Methods Three hundred and forty-eight breast cancer patients presenting a familial recurrence of invasive breast or ovarian carcinoma with at least two affected family members were screened for BRCA1-2 mutations by DHPLC analysis and DNA sequencing. Association of BRCA1 and BRCA2 mutational status with clinical and pathological parameters was evaluated by Pearson's Chi-Squared test. Results and Conclusion Overall, 8 BRCA1 and 5 BRCA2 deleterious mutations were detected in 35/348 (10%) families; majority (23/35;66%) of mutations was found in BRCA2 gene. The geographical distribution of BRCA1-2 mutations was related to three specific large areas of Sardinia, reflecting its ancient history: a) the Northern area, linguistically different from the rest of the island (where a BRCA2 c.8764_8765delAG mutation with founder effect was predominant); b) the Middle area, land of the ancient Sardinian population (where BRCA2 mutations are still more common than BRCA1 mutations); and c) the South-Western area, with many Phoenician and Carthaginian locations (where BRCA1 mutations are prevalent). We also found that phenotypic features such as high tumor grading and lack of expression of estrogen/progesterone receptors together with age at diagnosis and presence of ovarian cancer in the family may be predictive for the presence of BRCA1-2 germline mutations. PMID:19619314

  20. Isolation of the mouse homologue of BRCA1 and genetic mapping to mouse chromosome 11

    SciTech Connect

    Bennett, L.M.; Haugen-Strano, A.; Cochran, C.

    1995-10-10

    The BRCA1 gene is in large part responsible for hereditary human breast and ovarian cancer. Here we report the isolation of the murine Brca1 homologue cDNA clones. In addition, we identified genomic P1 clones that contain most, if not all, of the mouse Brca1 locus. DNA sequence analysis revealed that the mouse and human coding regions are 75% identical at the nucleotide level while the predicted amino acid identity is only 58%. A DNA sequence variant in the Brcal locus was identified and used to map this gene on a (Mus m. musculus Czech II x C57BL/KsJ)F1 x C57BL/KsJ intersubspecific backcross to distal mouse chromosome 11. The mapping of this gene to a region highly syntenic with human chromosome 17, coupled with Southern and Northern analyses, confirms that we isolated the murine Brcal homologue rather than a related RING finger gene. The isolation of the mouse Brca1 homologue will facilitate the creation of mouse models for germline BRCA1 defects. 12 refs., 3 figs.

  1. Conditional inactivation of Brca1 in the mouse ovarian surface epithelium results in an increase in preneoplastic changes

    SciTech Connect

    Clark-Knowles, Katherine V. . E-mail: kclar075@uottawa.ca; Garson, Kenneth; Jonkers, Jos; Vanderhyden, Barbara C.

    2007-01-01

    Epithelial ovarian cancer (EOC) is thought to arise from the ovarian surface epithelium (OSE); however, the molecular events underlying this transformation are poorly understood. Germline mutations in the BRCA1 tumor suppressor gene result in a significantly increased risk of developing EOC and a large proportion of sporadic EOCs display some sort of BRCA1 dysfunction. Using mice with conditional expression of Brca1, we inactivated Brca1 in the murine OSE and demonstrate that this inactivation results in the development of preneoplastic changes, such as hyperplasia, epithelial invaginations, and inclusion cysts, which arise earlier and are more numerous than in control ovaries. These changes resemble the premalignant lesions that have been reported in human prophylactic oophorectomy specimens from women with BRCA1 germline mutation. We also report that inactivation of Brca1 in primary cultures of murine OSE cells leads to a suppression of proliferation due to increased apoptosis that can be rescued by concomitant inactivation of p53. These observations, along with our finding that these cells display an increased sensitivity to the DNA-damaging agent cisplatin, indicate that loss of function of Brca1 in OSE cells impacts both cellular growth control and DNA-damage repair which results in altered cell behavior manifested as morphological changes in vivo that arise earlier and are more numerous than what can be attributed to ageing.

  2. Quantitative copy number analysis by Multiplex Ligation-dependent Probe Amplification (MLPA) of BRCA1-associated breast cancer regions identifies BRCAness

    PubMed Central

    2011-01-01

    Introduction Our group has previously employed array Comparative Genomic Hybridization (aCGH) to assess the genomic patterns of BRCA1-mutated breast cancers. We have shown that the so-called BRCA1-likeaCGH profile is also present in about half of all triple-negative sporadic breast cancers and is predictive for benefit from intensified alkylating chemotherapy. As aCGH is a rather complex method, we translated the BRCA1aCGH profile to a Multiplex Ligation-dependent Probe Amplification (MLPA) assay, to identify both BRCA1-mutated breast cancers and sporadic cases with a BRCA1-likeaCGH profile. Methods The most important genomic regions of the original aCGH based classifier (3q22-27, 5q12-14, 6p23-22, 12p13, 12q21-23, 13q31-34) were mapped to a set of 34 MLPA probes. The training set consisted of 39 BRCA1-likeaCGH breast cancers and 45 non-BRCA1-likeaCGH breast cancers, which had previously been analyzed by aCGH. The BRCA1-likeaCGH group consisted of germline BRCA1-mutated cases and sporadic tumours with low BRCA1 gene expression and/or BRCA1 promoter methylation. We trained a shrunken centroids classifier on the training set and validation was performed on an independent test set of 40 BRCA1-likeaCGH breast cancers and 32 non-BRCA1-likeaCGH breast cancer tumours. In addition, we validated the set prospectively on 69 new triple-negative tumours. Results BRCAness in the training set of 84 tumours could accurately be predicted by prediction analysis of microarrays (PAM) (accuracy 94%). Application of this classifier on the independent validation set correctly predicted BRCA-like status of 62 out of 72 breast tumours (86%). Sensitivity and specificity were 85% and 87%, respectively. When the MLPA-test was subsequently applied to 46 breast tumour samples from a randomized clinical trial, the same survival benefit for BRCA1-like tumours associated with intensified alkylating chemotherapy was shown as was previously reported using the aCGH assay. Conclusions Since the MLPA

  3. [Should knowledge of BRCA1 status impact the choice of chemotherapy in metastatic breast cancer: a review].

    PubMed

    Clergue, Océane; Jones, Natalie; Sévenet, Nicolas; Quenel-Tueux, Nathalie; Debled, Marc

    2015-03-01

    BRCA1 and BRCA2 mutations account for 40% of cancer predisposition gene mutations identified in the current French diagnostic setting. The proteins encoded by these genes are implicated in DNA repair pathways. As a result, loss of BRCA1 or BRCA2 function may modify chemo-sensitivity. This literature review aims to determine whether BRCA1 mutation status should influence the choice of systemic treatment in breast cancer. Fourteen articles and four abstracts from 12 retrospective analyses and 6 prospective studies were identified in the literature review. CMF-type and taxane-based protocols appear to be insufficiently effective, while anthracycline activity does not seem to be affected by BRCA1 status. BRCA1-mutated tumours appear to be highly sensitive to platinum, in both the neoadjuvant and metastatic setting. Olaparib, a PARP inhibitor, has only been evaluated in one study in metastatic patients, with promising results. The presence of a BRCA1 mutation can lead to an adaptation of therapies in the metastatic stages in breast cancer. The rapid identification of BRCA1 mutations and the adaptation of treatment according to this status in the (neo)adjuvant setting is likely to become a reality in the coming years. PMID:25758301

  4. Recurrent BRCA1 and BRCA2 mutations in breast cancer patients of African ancestry.

    PubMed

    Zhang, Jing; Fackenthal, James D; Zheng, Yonglan; Huo, Dezheng; Hou, Ningqi; Niu, Qun; Zvosec, Cecilia; Ogundiran, Temidayo O; Hennis, Anselm J; Leske, Maria Cristina; Nemesure, Barbara; Wu, Suh-Yuh; Olopade, Olufunmilayo I

    2012-07-01

    Recurrent mutations constituted nearly three quarters of all BRCA1 mutations and almost half of all BRCA2 mutations identified in the first cohort of the Nigerian Breast Cancer Study. To further characterize breast/ovarian cancer risks associated with BRCA1/BRCA2 mutations in the African diaspora, we genotyped recurrent mutations among Nigerian, African American, and Barbadian breast cancer patients. A replication cohort of 356 Nigerian breast cancer patients was genotyped for 12 recurrent BRCA1/2 mutant alleles (Y101X, 1742insG, 4241delTG, M1775R, 4359insC, C64Y, 1623delTTAAA, Q1090X, and 943ins10 from BRCA1, and 1538delAAGA, 2630del11, and 9045delGAAA from BRCA2) by means of SNaPshot followed by direct sequencing or by direct sequencing alone. In addition, 260 African Americans and 118 Barbadians were genotyped for six of the recurrent BRCA1 mutations by SNaPshot assay. Of all the BRCA1/2 recurrent mutations we identified in the first cohort, six were identified in 11 patients in the replication study. These mutation carriers constitute 3.1 % [95 % Confidence Interval (CI) 1.6-5.5 %] of the replication cohort. By comparison, 6.9 % (95 % CI 4.7-9.7 %) of the discovery cohort carried BRCA1/2 recurrent mutations. For the subset of recurrent mutations we tested in breast cancer cases from Barbados or the United States, only two 943ins10 carriers were identified in African Americans. Nigerian breast cancer patients from Ibadan carry a broad and unique spectrum of BRCA1/2 mutations. Our data suggest that BRCA1/2 mutation testing limited to recurrent mutations is not sufficient to understand the BRCA1/2-associated breast cancer risk in African populations in the diaspora. As the cost of Sanger sequencing is considerably reduced, deploying innovative technologies such as high throughput DNA sequencing of BRCA1/2 and other cancer susceptibility genes will be essential for identifying high-risk individuals and families to reduce the burden of aggressive early onset breast

  5. Characterization of three alternative transcripts of the BRCA1 gene in patients with breast cancer and a family history of breast and/or ovarian cancer who tested negative for pathogenic mutations

    PubMed Central

    GAMBINO, GAETANA; TANCREDI, MARIELLA; FALASCHI, ELISABETTA; ARETINI, PAOLO; CALIGO, MARIA ADELAIDE

    2015-01-01

    The study of BRCA1 and BRCA2 genes and their alterations has been essential to the understanding of the development of familial breast and ovarian cancers. Many of the variants identified have an unknown pathogenic significance. These include variants which determine alternative mRNA splicing, identified in the intronic regions and those are capable of destroying the splicing ability. The aim of this study was to detect BRCA1/BRCA2 aberrant transcripts resulting from alternative splicing, in women with a known family history and/or early onset of breast and/or ovarian cancer, tested wild-type for BRCA1 and BRCA2. The identification and characterization of aberrant transcripts through the analysis of mRNA levels in blood lymphocytes may help us to recognize families otherwise misclassified as wild-type BRCA1 and BRCA2. Blood samples were collected from 13 women that had a family history of breast and/or ovarian cancer and tested negative for pathogenic mutations in the BRCA1 and BRCA2 genes. Total RNA was analyzed for the presence of BRCA1 and BRCA2 naturally occuring and pathological transcripts using RT-PCR. In 2 out of the 13 samples, 2 alternative transcripts of the BRCA1 gene were identified. These were probably pathogenic as they lacked exon 17 and exon 15, respectively, giving rise to a truncated protein. In addition to these, we identified the Δ17–19 transcript in 1 patient, which gives rise to a protein with an in-frame deletion of 69 amino acids. In conclusion, this study on alternative transcripts of the BRCA1 and BRCA2 genes revealed the presence of isoforms (prevalence of 15%) in blood samples from women with breast and ovarian cancer that were probably pathogenic, that were not detected by conventional methods of mutation screening based on direct sequencing of all coding regions, intron-exons junctions and MLPA analysis. PMID:25683334

  6. Toxicity of (neo)adjuvant chemotherapy for BRCA1- and BRCA2-associated breast cancer.

    PubMed

    Drooger, Jan C; Heemskerk-Gerritsen, Bernadette A M; Smallenbroek, Nyrée; Epskamp, Cynthia; Seynaeve, Caroline M; Jager, Agnes

    2016-04-01

    Treatment with (neo)adjuvant chemotherapy for breast cancer, as currently given, causes cell damage by induction of double-strand DNA breaks. Because BRCA1 and BRCA2 proteins play a role in the repair of DNA damage, the efficacy of (neo)adjuvant chemotherapy may be increased in BRCA1/2-associated breast cancer patients. As a downside, acute chemotherapy-related toxicity may also be increased. We selected all female patients who were treated at the Erasmus MC Cancer Institute, with (neo)adjuvant chemotherapy for primary or locoregional recurrence of breast cancer (PBC/LR) between January 1, 2004 and December 31, 2014. The primary outcome was the relative total dose intensity (RTDI), calculated for anthracyclines and taxanes separately. Secondary outcomes were the occurrence of febrile neutropenia, delay in chemotherapy administration, and switch to another chemotherapy regimen due to toxicity. In total, 701 patients treated for PBC/LR were eligible for data analyses, among which 85 BRCA1/2 mutation carriers (n = 67 BRCA1 and n = 18 BRCA2). The mean RTDI for anthracyclines was not significantly different between both groups (98.7 % in the BRCA1/2, 96.6 % in the sporadic group, p = 0.27). Also the mean RTDI for taxanes was not significantly different between the groups (93.6 % in the BRCA1/2-associated, 90.0 % in the sporadic group, p = 0.12). Linear regression analysis revealed no significant effect of BRCA1/2 mutation carriership on the RTDIs. No significant differences were found in the percentages of patients presenting with febrile neutropenia, having a delay in chemotherapy administration or switching to an altered chemotherapy regimen. Additionally, the odds ratios showed no significant effect of BRCA1/2 mutation carriership on the secondary outcome variables. (Neo)adjuvant chemotherapy-related toxicity was not different between BRCA1/2-associated and sporadic breast cancer patients suggesting that the DNA damage repair mechanism of non-cancer cells

  7. A method to assess the clinical significance of unclassified variants in the BRCA1 and BRCA2 genes based on cancer family history

    PubMed Central

    Gómez García, Encarna B; Oosterwijk, Jan C; Timmermans, Maarten; van Asperen, Christi J; Hogervorst, Frans BL; Hoogerbrugge, Nicoline; Oldenburg, Rogier; Verhoef, Senno; Dommering, Charlotte J; Ausems, Margreet GEM; van Os, Theo AM; van der Hout, Annemarie H; Ligtenberg, Marjolijn; van den Ouweland, Ans; van der Luijt, Rob B; Wijnen, Juul T; Gille, Jan JP; Lindsey, Patrick J; Devilee, Peter; Blok, Marinus J; Vreeswijk, Maaike PG

    2009-01-01

    Introduction Unclassified variants (UVs) in the BRCA1/BRCA2 genes are a frequent problem in counseling breast cancer and/or ovarian cancer families. Information about cancer family history is usually available, but has rarely been used to evaluate UVs. The aim of the present study was to identify which is the best combination of clinical parameters that can predict whether a UV is deleterious, to be used for the classification of UVs. Methods We developed logistic regression models with the best combination of clinical features that distinguished a positive control of BRCA pathogenic variants (115 families) from a negative control population of BRCA variants initially classified as UVs and later considered neutral (38 families). Results The models included a combination of BRCAPRO scores, Myriad scores, number of ovarian cancers in the family, the age at diagnosis, and the number of persons with ovarian tumors and/or breast tumors. The areas under the receiver operating characteristic curves were respectively 0.935 and 0.836 for the BRCA1 and BRCA2 models. For each model, the minimum receiver operating characteristic distance (respectively 90% and 78% specificity for BRCA1 and BRCA2) was chosen as the cutoff value to predict which UVs are deleterious from a study population of 12 UVs, present in 59 Dutch families. The p.S1655F, p.R1699W, and p.R1699Q variants in BRCA1 and the p.Y2660D, p.R2784Q, and p.R3052W variants in BRCA2 are classified as deleterious according to our models. The predictions of the p.L246V variant in BRCA1 and of the p.Y42C, p.E462G, p.R2888C, and p.R3052Q variants in BRCA2 are in agreement with published information of them being neutral. The p.R2784W variant in BRCA2 remains uncertain. Conclusions The present study shows that these developed models are useful to classify UVs in clinical genetic practice. PMID:19200354

  8. Suppression of tumorigenicity of breast cancer cells by transfer of human chromosome 17 does not require transferred BRCA1 and p53 genes.

    PubMed

    Theile, M; Hartmann, S; Scherthan, H; Arnold, W; Deppert, W; Frege, R; Glaab, F; Haensch, W; Scherneck, S

    1995-02-01

    A number of candidate tumor suppressor genes located on the human chromosome 17 are thought to have a role to play in the development of breast cancer. In addition to the p53 gene on 17p13.1 and the BRCA1 gene mapped to 17q12-21, other chromosomal regions for tumor suppressor genes have been suggested to exist on 17p13.3 and both the central and the distal parts of 17q, although definitive functional proof of their involvement in breast cancer tumorigenesis is still lacking. In this report we show that microcell transfer of a human chromosome 17 into wild-type p53 breast cancer cells CAL51 results in loss of tumorigenicity and anchorage-independent growth, changes in cell morphology and a reduction of cell growth rates of the neo-selected microcell hybrids. In the hybrid cells, which express the p53 wild-type protein, only the p- and the distal parts of the q arm of donor chromosome 17 are transferred. Thus, our results provide functional evidence for the presence of one or more tumor suppressor gene(s) on chromosome 17, which are distinct from the p53 and the BRCA1 genes. PMID:7845668

  9. Ovarian carcinomas with genetic and epigenetic BRCA1 loss have distinct molecular abnormalities

    SciTech Connect

    Gilks, C. Blake; Press, Joshua Z.; De Luca, Alessandro; Boyd, Niki; Young, Sean; Troussard, Armelle; Ridge, Yolanda; Kaurah, Pardeep; Kalloger, Steve E.; Blood, Katherine A.; Smith, Margaret; Spellman, Paul T.; Wang, Yuker; Miller, Dianne M.; Horsman, Doug; Faham, Malek; Gilks, C. Blake; Gray, Joe; Huntsman, David G.

    2008-05-02

    Subclassification of ovarian carcinomas can be used to guide treatment and determine prognosis. Germline and somatic mutations, loss of heterozygosity (LOH), and epigenetic events such as promoter hypermethylation can lead to decreased expression of BRCA1/2 in ovarian cancers. The mechanism of BRCA1/2 loss is a potential method of subclassifying high grade serous carcinomas. A consecutive series of 49 ovarian cancers was assessed for mutations status of BRCA1 and BRCA2, LOH at the BRCA1 and BRCA2 loci, methylation of the BRCA1 promoter, BRCA1, BRCA2, PTEN, and PIK3CA transcript levels, PIK3CA gene copy number, and BRCA1, p21, p53, and WT-1 immunohistochemistry. Eighteen (37%) of the ovarian carcinomas had germline or somatic BRCA1 mutations, or epigenetic loss of BRCA1. All of these tumors were high-grade serous or undifferentiated type. None of the endometrioid (n=5), clear cell (n=4), or low grade serous (n=2) carcinomas showed loss of BRCA1, whereas 47% of the 38 high-grade serous or undifferentiated carcinomas had loss of BRCA1. It was possible to distinguish high grade serous carcinomas with BRCA1 mutations from those with epigenetic BRCA1 loss: tumors with BRCA1 mutations typically had decreased PTEN mRNA levels while those with epigenetic loss of BRCA1 had copy number gain of PIK3CA. Overexpression of p53 with loss of p21 expression occurred significantly more frequently in high grade serous carcinomas with epigenetic loss of BRCA1, compared to high grade serous tumors without loss of BRCA1. High grade serous carcinomas can be subclassified into three groups: BRCA1 loss (genetic), BRCA1 loss (epigenetic), and no BRCA1 loss. Tumors in these groups show distinct molecular alterations involving the PI3K/AKT and p53 pathways.

  10. Ovarian carcinomas with genetic and epigenetic BRCA1 loss havedistinct molecular abnormalities

    SciTech Connect

    Press, Joshua Z.; De Luca, Alessandro; Boyd, Niki; Young, Sean; Troussard, Armelle; Ridge, Yolanda; Kaurah, Pardeep; Kalloger, Steve E.; Blood, Katherine A.; Smith, Margaret; Spellman, Paul T.; Wang, Yuker; Miller, Dianne M.; Horsman, Doug; Faham, Malek; Gilks, C. Blake; Gray,Joe; Huntsman, David G.

    2007-07-23

    Subclassification of ovarian carcinomas can be used to guide treatment and determine prognosis. Germline and somatic mutations, loss of heterozygosity (LOH), and epigenetic events such as promoter hypermethylation can lead to decreased expression of BRCA1/2 in ovarian cancers. The mechanism of BRCA1/2 loss is a potential method of subclassifying high grade serous carcinomas. A consecutive series of 49 ovarian cancers was assessed for mutations status of BRCA1 and BRCA2, LOH at the BRCA1 and BRCA2 loci, methylation of the BRCA1 promoter, BRCA1, BRCA2, PTEN, and PIK3CA transcript levels, PIK3CA gene copy number, and BRCA1, p21, p53, and WT-1 immunohistochemistry. Eighteen (37%) of the ovarian carcinomas had germline or somatic BRCA1 mutations, or epigenetic loss of BRCA1. All of these tumors were high-grade serous or undifferentiated type. None of the endometrioid (n = 5), clear cell (n = 4), or low grade serous (n = 2) carcinomas showed loss of BRCA1, whereas 47% of the 38 high-grade serous or undifferentiated carcinomas had loss of BRCA1. It was possible to distinguish high grade serous carcinomas with BRCA1 mutations from those with epigenetic BRCA1 loss: tumors with BRCA1 mutations typically had decreased PTEN mRNA levels while those with epigenetic loss of BRCA1 had copy number gain of PIK3CA. Overexpression of p53 with loss of p21 expression occurred significantly more frequently in high grade serous carcinomas with epigenetic loss of BRCA1, compared to high grade serous tumors without loss of BRCA1. High grade serous carcinomas can be subclassified into three groups: BRCA1 loss (genetic), BRCA1 loss (epigenetic), and no BRCA1 loss. Tumors in these groups show distinct molecular alterations involving the PI3K/AKT and p53 pathways.

  11. Regulation of BRCA1, BRCA2 and BARD1 intracellular trafficking.

    PubMed

    Henderson, Beric R

    2005-09-01

    The subcellular location and function of many proteins are regulated by nuclear-cytoplasmic shuttling. BRCA1 and BARD1 provide an interesting model system for understanding the influence of protein dimerization on nuclear transport and localization. These proteins function predominantly in the nucleus to regulate cell cycle progression, DNA repair/recombination and gene transcription, and their export to the cytoplasm has been linked to apoptosis. Germ-line mutations in the BRCA1/BRCA2 and BARD1 genes predispose to risk of breast/ovarian cancer, and certain mutations impair protein function and nuclear accumulation. BRCA1 and BARD1 shuttle between the nucleus and cytoplasm; however heterodimerization masks the nuclear export signals located within each protein, causing nuclear retention of the BRCA1-BARD1 complex and potentially influencing its role in DNA repair, cell survival and regulation of centrosome duplication. This review discusses BRCA1, BRCA2 and BARD1 subcellular localization with emphasis on regulation of transport by protein dimerization and its functional implications. PMID:16108063

  12. High frequency of BRCA1, but not CHEK2 or NBS1 (NBN), founder mutations in Russian ovarian cancer patients

    PubMed Central

    Suspitsin, Evgeny N; Sherina, Nathalia Yu; Ponomariova, Daria N; Sokolenko, Anna P; Iyevleva, Aglaya G; Gorodnova, Tatyana V; Zaitseva, Olga A; Yatsuk, Olga S; Togo, Alexandr V; Tkachenko, Nathalia N; Shiyanov, Grigory A; Lobeiko, Oksana S; Krylova, Nadezhda Yu; Matsko, Dmitry E; Maximov, Sergey Ya; Urmancheyeva, Adel F; Porhanova, Nathalia V; Imyanitov, Evgeny N

    2009-01-01

    Background A significant portion of ovarian cancer (OC) cases is caused by germ-line mutations in BRCA1 or BRCA2 genes. BRCA testing is cheap in populations with founder effect and therefore recommended for all patients with OC diagnosis. Recurrent mutations constitute the vast majority of BRCA defects in Russia, however their impact in OC morbidity has not been yet systematically studied. Furthermore, Russian population is characterized by a relatively high frequency of CHEK2 and NBS1 (NBN) heterozygotes, but it remains unclear whether these two genes contribute to the OC risk. Methods The study included 354 OC patients from 2 distinct, geographically remote regions (290 from North-Western Russia (St.-Petersburg) and 64 from the south of the country (Krasnodar)). DNA samples were tested by allele-specific PCR for the presence of 8 founder mutations (BRCA1 5382insC, BRCA1 4153delA, BRCA1 185delAG, BRCA1 300T>G, BRCA2 6174delT, CHEK2 1100delC, CHEK2 IVS2+1G>A, NBS1 657del5). In addition, literature data on the occurrence of BRCA1, BRCA2, CHEK2 and NBS1 mutations in non-selected ovarian cancer patients were reviewed. Results BRCA1 5382insC allele was detected in 28/290 (9.7%) OC cases from the North-West and 11/64 (17.2%) OC patients from the South of Russia. In addition, 4 BRCA1 185delAG, 2 BRCA1 4153delA, 1 BRCA2 6174delT, 2 CHEK2 1100delC and 1 NBS1 657del5 mutation were detected. 1 patient from Krasnodar was heterozygous for both BRCA1 5382insC and NBS1 657del5 variants. Conclusion Founder BRCA1 mutations, especially BRCA1 5382insC variant, are responsible for substantial share of OC morbidity in Russia, therefore DNA testing has to be considered for every OC patient of Russian origin. Taken together with literature data, this study does not support the contribution of CHEK2 in OC risk, while the role of NBS1 heterozygosity may require further clarification. PMID:19338682

  13. BRCA1 mutations in primary breast and ovarian carcinomas

    SciTech Connect

    Futreal, P.A.; Cochran, C.; Bennett, L.M.; Haugen-Strano, A.; Terry, L.; Barrett, J.C.; Wiseman, R.; Liu, Q.; Shattuck-Eidens, D.; Harshman, K.

    1994-10-07

    Loss of heterozygosity data from familial tumors suggested that BRCA1, a gene that confers susceptibility to ovarian and early-onset breast cancer, encodes a tumor suppressor. The BRCA1 region is also subject to allelic loss in sporadic breast and ovarian cancers, an indication that BRCA1 mutations may occur somatically in these tumors. The BRCA1 coding region was examined for mutations in primary breast and ovarian tumors that show allele loss at the BRCA1 locus. Mutations were detected in 3 of 32 breast and 1 of 12 ovarian carcinomas; all four mutations were germline alterations and occurred in early-onset cancers. These results suggest that mutation of BRCA1 may not be critical in the development of the majority of breast and ovarian cancers that arise in the absence of a mutant germline allele.

  14. BRCA1 loses the ring but lords over resistance.

    PubMed

    Powell, Simon N

    2016-08-01

    Germline breast cancer 1 (BRCA1) variants are associated with a high risk of breast and ovarian cancers. Many BRCA1-mediated cancers are initially responsive to platinum-based therapy; however, resistance commonly develops. The BRCA1185delAG mutation is common in the Ashkenazi Jewish population and has been thought to result in loss of function due to the introduction of a stop codon in the 5' region of the BRCA1 transcript. Two studies in this issue of the JCI reveal that the BRCA1185delAG mutation results in the production of BRCA1 that lacks the N-terminal really interesting new gene (RING) domain. RING-less BRCA1 was shown to directly mediate chemoresistance, while maintaining some homologous recombination function. These results provide important insight into BRCA1 function and indicate that other truncated proteins could arise through similar alterations in codon usage. PMID:27454288

  15. Comprehensive BRCA1 and BRCA2 mutational profile in Lithuania.

    PubMed

    Janavičius, Ramūnas; Rudaitis, Vilius; Mickys, Ugnius; Elsakov, Pavel; Griškevičius, Laimonas

    2014-05-01

    There is limited knowledge about the BRCA1/2 mutational profile in Lithuania. We aimed to define the full BRCA1 and BRCA2 mutational spectrum and the clinically relevant prevalence of these gene mutations in Lithuania. A data set of 753 unrelated probands, recruited through a clinical setting, was used and consisted of 380 female breast cancer cases, 213 epithelial ovarian cancer cases, 20 breast and ovarian cancer cases, and 140 probands with positive family history of breast or ovarian cancer. A comprehensive mutation analysis of the BRCA1/2 genes by high resolution melting analysis coupled with Sanger sequencing and multiplex ligation-dependent probe amplification analysis was performed. Genetic analysis revealed 32 different pathogenic germline BRCA1/2 mutations: 20 in the BRCA1 gene and 12 in the BRCA2 gene, including four different large genomic rearrangements in the BRCA1 gene. In all, 10 novel BRCA1/2 mutations were found. Nine different recurrent BRCA1 mutations and two recurrent BRCA2 mutations were identified, which comprised 90.4% of all BRCA1/2 mutations. BRCA1 exon 1-3 deletion and BRCA2 c.658_659del are reported for the first time as recurrent mutations, pointing to a possible Baltic founder effect. Approximately 7% of breast cancer and 22% of ovarian cancer patients without family history and an estimated 0.5-0.6% of all Lithuanian women were found to be carriers of mutations in the BRCA1 or BRCA2 gene. PMID:25066507

  16. Ionizing radiation or mitomycin-induced micronuclei in lymphocytes of BRCA1 or BRCA2 mutation carriers.

    PubMed

    Gutiérrez-Enríquez, Sara; Ramón Y Cajal, Teresa; Alonso, Carmen; Corral, Anna; Carrasco, Pablo; Cornet, Mónica; Sanz, Judith; Ribas, Montserrat; Baiget, Montserrat; Diez, Orland

    2011-06-01

    BRCA1 and BRCA2 genes are essential in preserving the integrity of genome, and it is not unambiguously clear whether the heterozygosity status may affect BRCA1 or BRCA2 functions. This may have implications for the clinical management of BRCA1 and BRCA2 mutation carriers both in breast cancer (BC) screening modality and in cancer treatment based on DNA-damaging or DNA-repair-inhibiting drugs. We investigated whether lymphocytes carrying BRCA1 or BRCA2 mutations displayed an increased sensitivity to radiation or mitomycin C (MMC) in vitro treatments. Peripheral blood from 21 BRCA1 mutation carriers (12 with BC and 9 healthy), 24 BRCA2 carriers (13 with BC and 11 healthy), 15 familial BC patients without detected mutation in BRCA1 or BRCA2 and 16 controls without familial history of cancer (5 with BC and 11 healthy) were irradiated or treated with MMC. Chromosomal damage was measured using the cytokinesis-block micronucleus assay. We evaluated micronuclei (MN) and nucleoplasmic bridges (NPBs). The BRCA2 mutation carriers and familial BC patients without detected mutation in BRCA1 or BRCA2 showed less basal NPB than BRCA1 carriers and controls. The BRCA1 (+/-) or BRCA2 (+/-) lymphocytes did not have increased frequencies of MN or NPB after irradiation. In contrast, BRCA2 (+/-) lymphocytes presented higher levels of MN after MMC exposure than BRCA1 carriers and controls. The monoallelic BRCA1 or BRCA2 pathogenic mutations seem not to be associated with an enhanced radiosensitivity. The mutation of one BRCA2 allele conferred an increased sensitivity to MMC, presumably because of the role of this gene in the repair of MMC-induced DNA damage. This finding indicates that the MMC-induced MN analysis could be useful in identifying functional deficiencies of BRCA2 or genes related to BRCA2. Since MMC can be used as an anti-cancer drug, these data may be relevant for the management and follow-up of BRCA2 mutation carriers. PMID:20625817

  17. BRCA1/2 mutations perturb telomere biology: characterization of structural and functional abnormalities in vitro and in vivo

    PubMed Central

    Zuriano, Lital; Naser, Shaden; Beery, Einat; Nordenberg, Jardena; Lubin, Ido; Adel, Yonatan; Shepshelovich, Daniel; Yavin, Hagai; Aharon, Irit Ben; Pery, Shlomit; Rizel, Shulamit; Pasmanik-Chor, Metsada; Frumkin, Dan; Lahav, Meir

    2016-01-01

    BRCA1 mutation is associated with carcinogenesis, especially of breast tissue. Telomere maintenance is crucial for malignant transformation. Being a part of the DNA repair machinery, BRCA1 may be implicated in telomere biology. We explored the role of BRCA1 in telomere maintenance in lymphocytes of BRCA1/2 mutation carriers and in in vitro system by knocking down its expression in non-malignant breast epithelial cells. The results in both systems were similar. BRCA1/2 mutation caused perturbation of telomere homeostasis, shortening of the single stranded telomere overhang and increased the intercellular telomere length variability as well as the number of telomere free chromosomal ends and telomeric circles. These changes resulted in an increased DNA damage status. Telomerase activity, inducibility and expression remained unchanged. BRCA1 mutation resulted also in changes in the binding of shelterin proteins to telomeres. DNMT-1 levels were markedly reduced both in the carriers and in in vitro system. The methylation pattern of the sub-telomeric regions in carriers suggested hypomethylation in chromosome 10. The expression of a distinct set of genes was also changed, some of which may relate to pre-disposition to malignancy. These results show that BRCA gene products have a role in telomere length homeostasis. It is plausible that these perturbations contribute to malignant transformation in BRCA mutants. PMID:26515461

  18. BRCA1/2 mutations perturb telomere biology: characterization of structural and functional abnormalities in vitro and in vivo.

    PubMed

    Uziel, Orit; Yerushalmi, Rinat; Zuriano, Lital; Naser, Shaden; Beery, Einat; Nordenberg, Jardena; Lubin, Ido; Adel, Yonatan; Shepshelovich, Daniel; Yavin, Hagai; Ben Aharon, Irit; Pery, Shlomit; Rizel, Shulamit; Pasmanik-Chor, Metsada; Frumkin, Dan; Lahav, Meir

    2016-01-19

    BRCA1 mutation is associated with carcinogenesis, especially of breast tissue. Telomere maintenance is crucial for malignant transformation. Being a part of the DNA repair machinery, BRCA1 may be implicated in telomere biology. We explored the role of BRCA1 in telomere maintenance in lymphocytes of BRCA1/2 mutation carriers and in in vitro system by knocking down its expression in non-malignant breast epithelial cells.The results in both systems were similar. BRCA1/2 mutation caused perturbation of telomere homeostasis, shortening of the single stranded telomere overhang and increased the intercellular telomere length variability as well as the number of telomere free chromosomal ends and telomeric circles. These changes resulted in an increased DNA damage status. Telomerase activity, inducibility and expression remained unchanged. BRCA1 mutation resulted also in changes in the binding of shelterin proteins to telomeres. DNMT-1 levels were markedly reduced both in the carriers and in in vitro system. The methylation pattern of the sub-telomeric regions in carriers suggested hypomethylation in chromosome 10. The expression of a distinct set of genes was also changed, some of which may relate to pre-disposition to malignancy.These results show that BRCA gene products have a role in telomere length homeostasis. It is plausible that these perturbations contribute to malignant transformation in BRCA mutants. PMID:26515461

  19. Accuracy of recall of information about a cancer-predisposing BRCA1/2 gene mutation among patients and relatives

    PubMed Central

    Jacobs, Chris; Dancyger, Caroline; Smith, Jonathan A; Michie, Susan

    2015-01-01

    This observational study aimed to (i) compare the accuracy of information recalled by patients and relatives following genetic counselling about a newly identified BRCA1/2 mutation, (ii) identify differences in accuracy of information about genetics and hereditary cancer and (iii) investigate whether accuracy among relatives improved when information was provided directly by genetics health professionals. Semistructured interviews following results from consultations with 10 breast/ovarian cancer patients and 22 relatives were audio-recorded and transcribed. Information provided by the genetics health professional was tracked through the families and coded for accuracy. Accuracy was analysed using the Wilcoxon Signed-Ranks test. Sources of information were tested using Spearman's rank-order correlation coefficient. Fifty-three percent of the information recalled by patients was accurate. Accuracy of recall among relatives was significantly lower than that among patients (P=0.017). Both groups recalled a lower proportion of information about hereditary cancer than about genetics (P=0.005). Relatives who learnt the information from the patient alone recalled significantly less accurate information than those informed directly by genetics health professionals (P=0.001). Following genetic counselling about a BRCA1/2 mutation, accuracy of recall was low among patients and relatives, particularly about hereditary cancer. Multiple sources of information, including direct contact with genetics health professionals, may improve the accuracy of information among relatives. PMID:24848747

  20. A multigenic study on breast cancer risk associated with genetic polymorphisms of ER Alpha, COMT and CYP19 gene in BRCA1/BRCA2 negative Shanghai women with early onset breast cancer or affected relatives.

    PubMed

    Hu, Zhen; Song, Chuan-Gui; Lu, Jing-Song; Luo, Jian-Min; Shen, Zhen-Zhou; Huang, Wei; Shao, Zhi-Ming

    2007-12-01

    High penetrance genes such as BRCA1 or BRCA2 account for only a small proportion of familial breast cancer in Chinese population. Estrogen has been proposed to participate in the proliferation and carcinogenesis of breast cancer. To investigate the association between genetic polymorphisms in genes encoding estrogen metabolizing, estrogen biosynthesizing enzyme and estrogen receptor and the breast cancer risk in BRCA1/BRCA2 negative Shanghai women, we conducted a case-control study including 114 cases with early-onset breast cancer or affected relatives and 121 healthy controls. The genotypes of estrogen receptor alpha (ERalpha), aromatase (CYP19), and catechol-O-methyltransferase (COMT) genes were analyzed by direct DNA-sequencing. Compared with H/H genotype of COMT Val158Met, COMT Val158Met L/L genotype was associated with a nonsignificantly elevated risk of breast cancer (OR: 3.72; 95% CI: 0.99-13.96, P=0.051). There was no statistically significant difference in genotype frequency of the ERalpha PvuII, ERalpha XbaI and CYP19 Arg264Cys polymorphism between controls and cases. When stratified by menopausal status, COMT Val158Met L/L (OR: 11.94; 95% CI: 1.48-96.03, P=0.02) and ERalpha PvuII P/p genotypes (OR: 2.67; 95% CI: 1.01-7.05, P=0.048) were associated with a significantly elevated risk of breast cancer in premenopausal women, and there was a association between ERalpha XbaI x/x genotype and the nonsignificantly increased risk of breast cancer in premenopausal women (OR: 6.88; 95% CI: 0.80-59.15, P=0.079). The multigenic analysis showed maybe these high risk genotypes had combined effect on breast cancer risk. Our findings suggest that polymorphism of genes involving estrogen-metabolizing pathway, estrogen- biosynthesizing pathway and estrogen receptor pathway may play an important role in the etiology of BRCA1/2 negative breast cancer with hereditary predisposing factors. PMID:17562079

  1. BRCA1 and BRCA2: different roles in a common pathway of genome protection

    PubMed Central

    Roy, Rohini; Chun, Jarin; Powell, Simon N.

    2016-01-01

    The proteins encoded by the two major breast cancer susceptibility genes, BRCA1 and BRCA2, work in a common pathway of genome protection. However, the two proteins work at different stages in the DNA damage response (DDR) and in DNA repair. BRCA1 is a pleiotropic DDR protein that functions in both checkpoint activation and DNA repair, whereas BRCA2 is a mediator of the core mechanism of homologous recombination. The links between the two proteins are not well understood, but they must exist to explain the marked similarity of human cancer susceptibility that arises with germline mutations in these genes. As discussed here, the proteins work in concert to protect the genome from double-strand DNA damage during DNA replication. PMID:22193408

  2. Characterization of BRCA1 Protein Targeting, Dynamics, and Function at the Centrosome

    PubMed Central

    Brodie, Kirsty M.; Henderson, Beric R.

    2012-01-01

    BRCA1 is a DNA damage response protein and functions in the nucleus to stimulate DNA repair and at the centrosome to inhibit centrosome overduplication in response to DNA damage. The loss or mutation of BRCA1 causes centrosome amplification and abnormal mitotic spindle assembly in breast cancer cells. The BRCA1-BARD1 heterodimer binds and ubiquitinates γ-tubulin to inhibit centrosome amplification and promote microtubule nucleation; however regulation of BRCA1 targeting and function at the centrosome is poorly understood. Here we show that both N and C termini of BRCA1 are required for its centrosomal localization and that BRCA1 moves to the centrosome independently of BARD1 and γ-tubulin. Mutations in the C-terminal phosphoprotein-binding BRCT domain of BRCA1 prevented localization to centrosomes. Photobleaching experiments identified dynamic (60%) and immobilized (40%) pools of ectopic BRCA1 at the centrosome, and these are regulated by the nuclear export receptor CRM1 (chromosome region maintenance 1) and BARD1. CRM1 mediates nuclear export of BRCA1, and mutation of the export sequence blocked BRCA1 regulation of centrosome amplification in irradiated cells. CRM1 binds to undimerized BRCA1 and is displaced by BARD1. Photobleaching assays implicate CRM1 in driving undimerized BRCA1 to the centrosome and revealed that when BRCA1 subsequently binds to BARD1, it is less well retained at centrosomes, suggesting a mechanism to accelerate BRCA1 release after formation of the active heterodimer. Moreover, Aurora A binding and phosphorylation of BRCA1 enhanced its centrosomal retention and regulation of centrosome amplification. Thus, CRM1, BARD1 and Aurora A promote the targeting and function of BRCA1 at centrosomes. PMID:22262852

  3. Pathogenicity of the BRCA1 Missense Variant M1775K is Determined by the Disruption of the BRCT Phosphopeptide-Binding Pocket: a Multi-Modal Approach

    SciTech Connect

    Tischkowitz,M.; Hamel, N.; Carvalho, M.; Birrane, G.; Soni, A.; van Beers, E.; Joosse, S.; Wong, N.; Novak, D.; et al

    2008-01-01

    A number of germ-line mutations in the BRCA1 gene confer susceptibility to breast and ovarian cancer. However, it remains difficult to determine whether many single amino-acid (missense) changes in the BRCA1 protein that are frequently detected in the clinical setting are pathologic or not. Here, we used a combination of functional, crystallographic, biophysical, molecular and evolutionary techniques, and classical genetic segregation analysis to demonstrate that the BRCA1 missense variant M1775K is pathogenic. Functional assays in yeast and mammalian cells showed that the BRCA1 BRCT domains carrying the amino-acid change M1775K displayed markedly reduced transcriptional activity, indicating that this variant represents a deleterious mutation. Importantly, the M1775K mutation disrupted the phosphopeptide-binding pocket of the BRCA1 BRCT domains, thereby inhibiting the BRCA1 interaction with the proteins BRIP1 and CtIP, which are involved in DNA damage-induced checkpoint control. These results indicate that the integrity of the BRCT phosphopeptide-binding pocket is critical for the tumor suppression function of BRCA1. Moreover, this study demonstrates that multiple lines of evidence obtained from a combination of functional, structural, molecular and evolutionary techniques, and classical genetic segregation analysis are required to confirm the pathogenicity of rare variants of disease-susceptibility genes and obtain important insights into the underlying pathogenetic mechanisms.

  4. Identifying the Effects of BRCA1 Mutations on Homologous Recombination using Cells that Express Endogenous Wild-type BRCA1

    PubMed Central

    Parvin, Jeffrey; Chiba, Natsuko; Ransburgh, Derek

    2011-01-01

    expressed in these cells, it failed to restore BRCA1-dependent homologous recombination. By contrast, expression of another variant, also of unknown significance, BRCA1(I21V) fully restored BRCA1-dependent homologous recombination function. This strategy of testing the function of BRCA1 missense mutations has been applied to another biological system assaying for centrosome function (Kais et al, unpublished observations). Overall, this approach is suitable for the analysis of missense mutants in any gene that must be analyzed recessively. PMID:21372787

  5. Identification and functional characterization of a PP1-binding site in BRCA1

    PubMed Central

    Hsu, Lih-Ching

    2007-01-01

    The phosphorylation state of the tumor suppressor protein BRCA1 is tightly associated with its functions including cell cycle control and DNA repair. Protein kinases involved in the DNA damage checkpoint control, such as ATM, ATR, and hCds1/Chk2, have been shown to phosphorylate and activate BRCA1 upon DNA damage. We reported previously that protein phosphatase 1α(PP1α) interacts with and dephosphorylates hCds1/Chk2-phosphorylated BRCA1. This study demonstrates the identification of a PP1-binding motif 898KVTF901 in BRCA1. Mutation or deletion of critical residues in this PP1-binding motif substantially reduces the interaction between BRCA1 and PP1α. PP1α can also dephosphorylate ATM and ATR phosphorylation sites in BRCA1 and may serve as a general regulator for BRCA1 phosphorylation. Unlike wild-type BRCA1, expression of the PP1 non-binding mutant BRCA1 protein in BRCA1-deficient cells failed to enhance survival after DNA damage. Taken together, these results suggest that interaction with PP1α is important for BRCA1 function. PMID:17603999

  6. BRCA Genetic Screening in Middle Eastern and North African: Mutational Spectrum and Founder BRCA1 Mutation (c.798_799delTT) in North African

    PubMed Central

    Laraqui, Abdelilah; Uhrhammer, Nancy; EL Rhaffouli, Hicham; Sekhsokh, Yassine; Lahlou-Amine, Idriss; Bajjou, Tahar; Hilali, Farida; El Baghdadi, Jamila; Al Bouzidi, Abderrahmane; Bakri, Youssef; Amzazi, Said; Bignon, Yves-Jean

    2015-01-01

    Background. The contribution of BRCA1 mutations to both hereditary and sporadic breast and ovarian cancer (HBOC) has not yet been thoroughly investigated in MENA. Methods. To establish the knowledge about BRCA1 mutations and their correlation with the clinical aspect in diagnosed cases of HBOC in MENA populations. A systematic review of studies examining BRCA1 in BC women in Cyprus, Jordan, Egypt, Lebanon, Morocco, Algeria, and Tunisia was conducted. Results. Thirteen relevant references were identified, including ten studies which performed DNA sequencing of all BRCA1 exons. For the latter, 31 mutations were detected in 57 of the 547 patients ascertained. Familial history of BC was present in 388 (71%) patients, of whom 50 were mutation carriers. c.798_799delTT was identified in 11 North African families, accounting for 22% of total identified BRCA1 mutations, suggesting a founder allele. A broad spectrum of other mutations including c.68_69delAG, c.181T>G, c.5095C>T, and c.5266dupC, as well as sequence of unclassified variants and polymorphisms, was also detected. Conclusion. The knowledge of genetic structure of BRCA1 in MENA should contribute to the assessment of the necessity of preventive programs for mutation carriers and clinical management. The high prevalence of BC and the presence of frequent mutations of the BRCA1 gene emphasize the need for improving screening programs and individual testing/counseling. PMID:25814778

  7. Ovarian cancer in BRCA1 and BRCA2 gene mutation carriers: analysis of prognostic factors and survival

    PubMed Central

    Biglia, Nicoletta; Sgandurra, Paola; Bounous, Valentina Elisabetta; Maggiorotto, Furio; Piva, Eleonora; Pivetta, Emanuele; Ponzone, Riccardo; Pasini, Barbara

    2016-01-01

    Objectives To compare clinical–pathological characteristics and outcome between sporadic ovarian cancer and ovarian cancer in patents with hereditary breast and ovarian cancer syndrome (HBOC). Methods Twenty-four patients with ovarian cancer treated between 2000 and 2009 who tested positive for BRCA1/2 mutation (BRCA+) and a control group of 64 age-matched patients with no family history of breast/ovarian cancer (controls) were enrolled. Clinical–pathological characteristics, surgical outcome, overall (OS), and progression-free survival (PFS) were compared between the two groups. Results The high-grade serous histotype was more represented in BRCA+ than in controls (70.8% versus 53.1%) (p > 0.05). BRCA+ cancers were more frequently diagnosed at stage II than controls (20.83% versus 4.69%) (p = 0.024). Radical primary surgery was performed in 70% of women in both groups, with no difference in debulking results. In patients undergoing surgery after neoadjuvant chemotherapy, in all BRCA+ patients, optimal cytoreduction was achieved (versus 70% of the controls). PFS was significantly longer for BRCA+ patients compared to controls (60 months versus 22 months; p = 0.039). No significant difference was observed in OS between BRCA+ patients and controls. Conclusions At a median follow-up time of 46 months, BRCA+ patients have a better prognosis than controls in terms of PFS. Higher chemosensitivity of BRCA+ tumours was observed. PMID:27350785

  8. Preliminary crystallographic studies of BRCA1 BRCT-ABRAXAS complex.

    PubMed

    Badgujar, Dilip C; Sawant, Ulka; Yadav, Lumbini; Hosur, M V; Varma, Ashok K

    2013-12-01

    The BRCA1 holoenzyme complex plays an important role in DNA damage repair. ABRAXAS is a newly discovered component of this complex and its C-terminal region directly binds to the BRCA1 BRCT domain. Single crystals of the BRCA1 BRCT-ABRAXAS complex grown by co-crystallization belonged to space group P4(1)2(1)2, with unit-cell parameters a = b = 187.18, c = 85.31 Å. Diffraction data were collected on the BM-14 beamline at the ESRF. Molecular-replacement calculations using Phaser led to three molecules in the asymmetric unit and a high solvent content of 76%. PMID:24316840

  9. Comprehensive analysis of BRCA1, BRCA2 and TP53 germline mutation and tumor characterization: a portrait of early-onset breast cancer in Brazil.

    PubMed

    Carraro, Dirce Maria; Koike Folgueira, Maria Aparecida Azevedo; Garcia Lisboa, Bianca Cristina; Ribeiro Olivieri, Eloisa Helena; Vitorino Krepischi, Ana Cristina; de Carvalho, Alex Fiorini; de Carvalho Mota, Louise Danielle; Puga, Renato David; do Socorro Maciel, Maria; Michelli, Rodrigo Augusto Depieri; de Lyra, Eduardo Carneiro; Grosso, Stana Helena Giorgi; Soares, Fernando Augusto; Achatz, Maria Isabel Alves de Souza Waddington; Brentani, Helena; Moreira-Filho, Carlos Alberto; Brentani, Maria Mitzi

    2013-01-01

    Germline mutations in BRCA1, BRCA2 and TP53 genes have been identified as one of the most important disease-causing issues in young breast cancer patients worldwide. The specific defective biological processes that trigger germline mutation-associated and -negative tumors remain unclear. To delineate an initial portrait of Brazilian early-onset breast cancer, we performed an investigation combining both germline and tumor analysis. Germline screening of the BRCA1, BRCA2, CHEK2 (c.1100delC) and TP53 genes was performed in 54 unrelated patients <35 y; their tumors were investigated with respect to transcriptional and genomic profiles as well as hormonal receptors and HER2 expression/amplification. Germline mutations were detected in 12 out of 54 patients (22%) [7 in BRCA1 (13%), 4 in BRCA2 (7%) and one in TP53 (2%) gene]. A cancer familial history was present in 31.4% of the unrelated patients, from them 43.7% were carriers for germline mutation (37.5% in BRCA1 and in 6.2% in the BRCA2 genes). Fifty percent of the unrelated patients with hormone receptor-negative tumors carried BRCA1 mutations, percentage increasing to 83% in cases with familial history of cancer. Over-representation of DNA damage-, cellular and cell cycle-related processes was detected in the up-regulated genes of BRCA1/2-associated tumors, whereas cell and embryo development-related processes were over-represented in the up-regulated genes of BRCA1/2-negative tumors, suggesting distinct mechanisms driving the tumorigenesis. An initial portrait of the early-onset breast cancer patients in Brazil was generated pointing out that hormone receptor-negative tumors and positive familial history are two major risk factors for detection of a BRCA1 germline mutation. Additionally, the data revealed molecular factors that potentially trigger the tumor development in young patients. PMID:23469205

  10. Functional isogenic modeling of BRCA1 alleles reveals distinct carrier phenotypes

    PubMed Central

    Cochran, Rory L.; Cidado, Justin; Kim, Minsoo; Zabransky, Daniel J.; Croessmann, Sarah; Chu, David; Wong, Hong Yuen; Beaver, Julia A.; Cravero, Karen; Erlanger, Bracha; Parsons, Heather; Heaphy, Christopher M.; Meeker, Alan K.; Lauring, Josh; Park, Ben Ho

    2015-01-01

    Clinical genetic testing of BRCA1 and BRCA2 is commonly performed to identify specific individuals at risk for breast and ovarian cancers who may benefit from prophylactic therapeutic interventions. Unfortunately, it is evident that deleterious BRCA1 alleles demonstrate variable penetrance and that many BRCA1 variants of unknown significance (VUS) exist. In order to further refine hereditary risks that may be associated with specific BRCA1 alleles, we performed gene targeting to establish an isogenic panel of immortalized human breast epithelial cells harboring eight clinically relevant BRCA1 alleles. Interestingly, BRCA1 mutations and VUS had distinct, quantifiable phenotypes relative to isogenic parental BRCA1 wild type cells and controls. Heterozygous cells with known deleterious BRCA1 mutations (185delAG, C61G and R71G) demonstrated consistent phenotypes in radiation sensitivity and genomic instability assays, but showed variability in other assays. Heterozygous BRCA1 VUS cells also demonstrated assay variability, with some VUS demonstrating phenotypes more consistent with deleterious alleles. Taken together, our data suggest that BRCA1 deleterious mutations and VUS can differ in their range of tested phenotypes, suggesting they might impart varying degrees of risk. These results demonstrate that functional isogenic modeling of BRCA1 alleles could aid in classifying BRCA1 mutations and VUS, and determining BRCA allele cancer risk. PMID:26246475

  11. Functional isogenic modeling of BRCA1 alleles reveals distinct carrier phenotypes.

    PubMed

    Cochran, Rory L; Cidado, Justin; Kim, Minsoo; Zabransky, Daniel J; Croessmann, Sarah; Chu, David; Wong, Hong Yuen; Beaver, Julia A; Cravero, Karen; Erlanger, Bracha; Parsons, Heather; Heaphy, Christopher M; Meeker, Alan K; Lauring, Josh; Park, Ben Ho

    2015-09-22

    Clinical genetic testing of BRCA1 and BRCA2 is commonly performed to identify specific individuals at risk for breast and ovarian cancers who may benefit from prophylactic therapeutic interventions. Unfortunately, it is evident that deleterious BRCA1 alleles demonstrate variable penetrance and that many BRCA1 variants of unknown significance (VUS) exist. In order to further refine hereditary risks that may be associated with specific BRCA1 alleles, we performed gene targeting to establish an isogenic panel of immortalized human breast epithelial cells harboring eight clinically relevant BRCA1 alleles. Interestingly, BRCA1 mutations and VUS had distinct, quantifiable phenotypes relative to isogenic parental BRCA1 wild type cells and controls. Heterozygous cells with known deleterious BRCA1 mutations (185delAG, C61G and R71G) demonstrated consistent phenotypes in radiation sensitivity and genomic instability assays, but showed variability in other assays. Heterozygous BRCA1 VUS cells also demonstrated assay variability, with some VUS demonstrating phenotypes more consistent with deleterious alleles. Taken together, our data suggest that BRCA1 deleterious mutations and VUS can differ in their range of tested phenotypes, suggesting they might impart varying degrees of risk. These results demonstrate that functional isogenic modeling of BRCA1 alleles could aid in classifying BRCA1 mutations and VUS, and determining BRCA allele cancer risk. PMID:26246475

  12. BRCA1-associated Protein 1 (BAP1) Deubiquitinase Antagonizes the Ubiquitin-mediated Activation of FoxK2 Target Genes*

    PubMed Central

    Okino, Yuki; Machida, Yuka; Frankland-Searby, Sarah; Machida, Yuichi J.

    2015-01-01

    BRCA1-associated protein 1 (BAP1), which is frequently mutated in cancer, functions as a deubiquitinase (DUB) for histone H2A. Although BAP1 interacts with a transcriptional regulator, HCF-1, and transcription factors FoxK1 and FoxK2, how BAP1 controls gene expression remains unclear. This study investigates the importance of BAP1 DUB activity and the interactions with FoxK2 and HCF-1 in the regulation of FoxK2 target genes. We show that FoxK2 recruits BAP1 to the target genes through the forkhead-associated domain, which interacts with Thr(P)-493 on BAP1. BAP1, in turn, recruits HCF-1, thereby forming a ternary complex in which BAP1 bridges FoxK2 and HCF-1. BAP1 represses FoxK2 target genes, and this effect requires BAP1 DUB activity but not interaction with HCF-1. Importantly, BAP1 depletion causes up-regulation of FoxK2 target genes only in the presence of the Ring1B-Bmi1 complex, an E3 ubiquitin ligase for histone H2A, indicating an antagonizing role of BAP1 against Ring1B-Bmi1. Our findings suggest that BAP1 deficiency causes increased expression of target genes in a Ring1B-Bmi1-dependent manner. PMID:25451922

  13. Prevalence of mutations in a panel of breast cancer susceptibility genes in BRCA1/2 negative patients with early onset breast cancer

    PubMed Central

    Maxwell, Kara N.; Wubbenhorst, Bradley; D’Andrea, Kurt; Garman, Bradley; Long, Jessica M.; Powers, Jacquelyn; Rathbun, Katherine; Stopfer, Jill E.; Zhu, Jiajun; Bradbury, Angela R.; Simon, Michael S.; DeMichele, Angela; Domchek, Susan M.; Nathanson, Katherine L.

    2014-01-01

    Purpose Clinical testing for germline variation in multiple cancer susceptibility genes is available using massively parallel sequencing. Limited information is available for pre-test genetic counseling regarding the spectrum of mutations and variants of uncertain significance (VUSs) in defined patient populations. Methods We performed massively parallel sequencing using targeted capture of 22 cancer susceptibility genes in 278 BRCA1/2 negative patients with early onset breast cancer (diagnosed under age 40). Results Thirty-one patients (11%) were found to have at least one deleterious or likely deleterious variant. Seven patients (2.5% overall) were found to have deleterious or likely deleterious variants in genes for which clinical guidelines exist for management, namely TP53 (4), CDKN2A (1) MSH2 (1), and MUTYH (double heterozygote). Twenty-four patients (8.6%) had deleterious or likely deleterious variants in a cancer susceptibility gene for which clinical guidelines are lacking, such as CHEK2 and ATM. Fifty-four patients (19%) had at least one VUS, and six patients were heterozygous for a variant in MUTYH. Conclusion These data demonstrate that massively parallel sequencing identifies reportable variants in known cancer susceptibility genes in over 30% of patients with early onset breast cancer. However, only rare patients (2.5%) have definitively actionable mutations given current clinical management guidelines. PMID:25503501

  14. Detection of eight BRCA1 mutations in 10 breast/ovarian cancer families, including 1 family with male breast cancer

    SciTech Connect

    Sruewing, J.P.; Brody, L.C.; Erdos, M.R.

    1995-07-01

    Genetic epidemiological evidence suggests that mutations in BRCA1 may be responsible for approximately one half of early onset familial breast cancer and the majority of familial breast/ovarian cancer. The recent cloning of BRCA1 allows for the direct detection of mutations, but the feasibility of presymptomatic screening for cancer susceptibility is unknown. We analyzed genomic DNA from one affected individual from each of 24 families with at least three cases of ovarian or breast cancer, using SSCP assays. Variant SSCP bands were subcloned and sequenced. Allele-specific oligonucleotide hybridization was used to verify sequence changes and to screen DNA from control individuals. Six frameshift and two missense mutations were detected in 10 different families. A frameshift mutation was detected in a male proband affected with both breast and prostate cancer. A 40-bp deletion was detected in a patient who developed intra-abdominal carcinomatosis 1 year after prophylactic oophorectomy. Mutations were detected throughout the gene, and only one was detected in more than a single family. These results provide further evidence that inherited breast and ovarian cancer can occur as a consequence of a wide array of BRCA1 mutations. These results suggests that development of a screening test for BRCA1 mutations will be technically challenging. The finding of a mutation in a family with male breast cancer, not previously thought to be related to BRCA1, also illustrates the potential difficulties of genetic counseling for individuals known to carry mutations. 37 refs., 1 fig., 1 tab.

  15. The prognostic value of BRCA1 promoter methylation in early stage triple negative breast cancer

    PubMed Central

    Kimler, Bruce F.; Sethi, Geetika; Petroff, Brian K.; Phillips, Teresa A.; Tawfik, Ossama W.; Godwin, Andrew K.; Jensen, Roy A.

    2014-01-01

    Introduction Methylation of the BRCA1 promoter is frequent in triple negative breast cancers (TNBC) and results in a tumor phenotype similar to BRCA1-mutated tumors. BRCA1 mutation-associated cancers are more sensitive to DNA damaging agents as compared to conventional chemotherapy agents. It is not known if there is an interaction between the presence of BRCA1 promoter methylation (PM) and response to chemotherapy agents in sporadic TNBC. We sought to investigate the prognostic significance of BRCA1 PM in TNBC patients receiving standard chemotherapy. Methods Subjects with stage I-III TNBC treated with chemotherapy were identified and their formalin-fixed paraffin-embedded (FFPE) tumor specimens retrieved. Genomic DNA was isolated and subjected to methylation-specific PCR (MSPCR). Results DNA was isolated from primary tumor of 39 subjects. BRCA1 PM was detected in 30% of patients. Presence of BRCA1 PM was associated with lower BRCA1 transcript levels, suggesting epigenetic BRCA1 silencing. All patients received chemotherapy (anthracycline:90%, taxane:69%). At a median follow-up of 64 months, 46% of patients have recurred and 36% have died. On univariate analysis, African-American race, node positivity, stage, and BRCA1 PM were associated with worse RFS and OS. Five year OS was 36% for patients with BRCA1 PM vs. 77% for patients without BRCA1 PM (p=0.004). On multivariable analysis, BRCA1 PM was associated with significantly worse RFS and OS. Conclusions We show that BRCA1 PM is common in TNBC and has the potential to identify a significant fraction of TNBC patients who have suboptimal outcomes with standard chemotherapy. PMID:25177489

  16. [Should a systematic fertility preservation be proposed to healthy women carrying a BRCA1/2 mutation?].

    PubMed

    Sénéchal, C; Rousset-Jablonski, C

    2015-12-01

    Should all women with BRCA1 or BRCA2 genes mutations be considered at risk of prematurely impaired fertility, and thus should a fertility preservation systematically be proposed? Women carrying mutations of BRCA1 or BRCA2 are at high risk for breast and tubo-ovarian cancer. The treatment of a breast cancer at a young age, unrare in this population, is associated with a risk of infertility, due to the ovarian toxicity of chemotherapy, to the recommended duration of hormonotherapy when indicated, and to the time advised before starting a pregnancy. Furthermore, some data in the literature suggest a higher risk of premature ovarian failure among women with BRCA1/2 mutation: advance of the age at menopause and poorer response to ovarian stimulation have been observed. Several pathophysiological hypotheses support this finding, as the involvement of the BRCA genes in maintaining telomere length, the DNA repair anomalies promoting oocyte apoptosis, differences in FMR1 genotype. Current fertility preservation techniques have limitations, some of them being specific to BRCA1/2 women: absence of oncological risk due to stimulation in BRCA1/2 women not clearly demonstrated, oocyte vitrification techniques limited rentability, graft of ovarian cortex not suitable in these women at high risk. Thus, data on the increased risk of premature ovarian failure remaining weak, such a systematic proposal seems questionable. PMID:26476890

  17. Elevated Levels of Somatic Mutation in a Manifesting BRCA1 Mutation Carrier

    PubMed Central

    GRANT, Stephen G.; DAS, Rubina; CERCEO, Christina M.; RUBINSTEIN, Wendy S.; LATIMER, Jean J.

    2015-01-01

    Homozygous loss of activity at the breast cancer-predisposing genes BRCA1 and BRCA2 (FANCD1) confers increased susceptibility to DNA double strand breaks, but this genotype occurs only in the tumor itself, following loss of heterozygosity at one of these loci. Thus, if these genes play a role in tumor etiology as opposed to tumor progression, they must manifest a heterozygous phenotype at the cellular level. To investigate the potential consequences of somatic heterozygosity for a BRCA1 mutation demonstrably associated with breast carcinogenesis on background somatic mutational burden, we applied the two standard assays of in vivo human somatic mutation to blood samples from a manifesting carrier of the Q1200X mutation in BRCA1 whose tumor was uniquely ascertained through an MRI screening study. The patient had an allele-loss mutation frequency of 19.4 × 10−6 at the autosomal GPA locus in erythrocytes and 17.1 × 10−6 at the X-linked HPRT locus in lymphocytes. Both of these mutation frequencies are significantly higher than expected from age-matched disease-free controls (P < 0.05). Mutation at the HPRT locus was similarly elevated in lymphoblastoid cell lines established from three other BRCA1 mutation carriers with breast cancer. Our patient’s GPA mutation frequency is below the level established for diagnosis of homozygous Fanconi anemia patients, but consistent with data from obligate heterozygotes. The increased HPRT mutation frequency is more reminiscent of data from patients with xeroderma pigmentosum, a disease characterized by UV sensitivity and deficiency in the nucleotide excision pathway of DNA repair. Therefore, this BRCA1-associated breast cancer patient manifests a unique phenotype of increased background mutagenesis that likely contributed to the development of her disease independent of loss of heterozygosity at the susceptibility locus. PMID:18158561

  18. BRCA1 proteins regulate growth of ovarian cancer cells by tethering Ubc9

    PubMed Central

    Qin, Yunlong; Xu, Jingyao; Aysola, Kartik; Oprea, Gabriela; Reddy, Avinash; Matthews, Roland; Okoli, Joel; Cantor, Alan; Grizzle, William E; Partridge, Edward E; Reddy, E Shyam P; Landen, Charles; Rao, Veena N

    2012-01-01

    Mutation in the BRCA1 gene is associated with increased risk for hereditary breast and ovarian cancers. In sporadic ovarian tumors, BRCA1 dysfunction is thought to be common. BRCA1 is a nuclear-cytoplasm shuttling protein. Our group has previously reported that BRCA1 proteins, unlike K109R and cancer-predisposing mutant C61G BRCA1 proteins, bind the sole SUMO E2-conjugating enzyme Ubc9. In this study, we examined the result of altered Ubc9 binding and knockdown on the sub-cellular localization and growth inhibitory function of BRCA1 proteins in ovarian cancer cells. Using live imaging of YFP, RFP-tagged BRCA1 and BRCA1a proteins, our results show enhanced cytoplasmic localization of K109R and C61G mutant BRCA1 proteins in ES-2, NIHOVCAR3 and UWB 1.289 ovarian cancer cells. Down-regulation of Ubc9 in ovarian cancer cells using Ubc9 siRNA resulted in cytoplasmic localization of BRCA1 and BRCA1a proteins. These mutant BRCA1a proteins were impaired in their capacity to inhibit growth of ES-2 ovarian cancer cells. Several ovarian cancer cells, including a BRCA1-null ovarian cancer cell line, showed higher levels of expression of Ubc9. This is the first study demonstrating the physiological link between loss of Ubc9 binding and loss of growth suppression of disease-associated mutant BRCA1a proteins in ovarian cancer cells. BRCA1, by turning off or on Ubc9 binding, regulates growth of ovarian cancers. PMID:22957306

  19. HERC2 is an E3 ligase that targets BRCA1 for degradation.

    PubMed

    Wu, Wenwen; Sato, Ko; Koike, Ayaka; Nishikawa, Hiroyuki; Koizumi, Hirotaka; Venkitaraman, Ashok R; Ohta, Tomohiko

    2010-08-01

    The breast cancer suppressor BRCA1 forms a stable heterodimeric E3 ubiquitin ligase with BARD1. Each protein controls the abundance and stability of the other, and loss of the interaction leads to BRCA1 degradation. Here, we show that HERC2, a protein recently implicated in DNA damage repair, targets BARD1-uncoupled BRCA1 for degradation. HERC2 shuttles between the nucleus and the cytoplasm. Its COOH-terminal HECT-containing domain interacts with an NH(2)-terminal degron domain in BRCA1. HERC2 ubiquitinates BRCA1; this reaction depends on Cys(4762) of HERC2, the catalytic ubiquitin binding site, and the degron of BRCA1. The HERC2-BRCA1 interaction is maximal during the S phase of the cell cycle and rapidly diminishes as cells enter G(2)-M, inversely correlated with the steady-state level of BRCA1. Significantly, HERC2 depletion antagonizes the effects of BARD1 depletion by restoring BRCA1 expression and G(2)-M checkpoint activity. Conversely, BARD1 protects BRCA1 from HERC2-mediated ubiquitination. Collectively, our findings identify a function for HERC2 in regulating BRCA1 stability in opposition to BARD1. The HERC2 expression in breast epithelial cells and breast carcinomas suggests that this mechanism may play a role in breast carcinogenesis. PMID:20631078

  20. Haplotype analysis of BRCA1 intragenic markers in Iranian patients with familial breast and ovarian cancer

    PubMed Central

    Miresmaeili, Seyed Mohsen; Kordi Tamandani, Dor Mohammad; Kalantar, Seyed Mehdi; Moshtaghioun, Seyed Mohammad

    2016-01-01

    Background: Breast cancer is the most common malignancy in women. Breast Cancer Type 1 Susceptibility gene (BRCA1) is a tumor suppressor gene, involved in DNA damage repair and in 81% of the breast-ovarian cancer families were due to BRCA1. In some clinically investigated genes, the intragenic marker polymorphism is important and the screening of such mutations is faster by using short tandem repeat (STR) polymorphism. Individual polymorphism of STR is a good evidence for following inheritance of repeat polymorphism. Objective: The aim of this study was to evaluate three intragenic BRCA1 marker polymorphisms in families, which have two or more patients with breast/ovarian cancer in comparison to healthy women. Materials and Methods: A total of 107 breast and/or ovarian cancer patients and 93 unrelated healthy women with no clinical phenotype of any malignancy or familial cancer history constitute the study groups. Haplotyping analysis, at 3 intragenic BRCA1 microsatellite markers (D17S855, D17S1322 and D17S1323), were performed for all subject and control groups using labeled primers. Results: After fragment analysis, significance differences were observed as follows: two alleles of D17S855; allele 146 (p=0.02) and 150 (p=0.006), and two alleles of D17S1322, allele 121 (p=0.015) and 142 (p=0.043). These differences were compared with control group. There was significance difference in 8 di/tri allelic haplotypes in present experimental subjects. Some haplotypes were observed to have approximately twice the relation risk for breast cancer. Conclusion: According to recent results, assessment of presence or absence of mentioned alleles in BRCA1 microsatellite can be used for prognosis in individuals, suspected of having or not having the breast cancer. PMID:27351029

  1. ATR, BRCA1 and gammaH2AX localize to unsynapsed chromosomes at the pachytene stage in human oocytes.

    PubMed

    Garcia-Cruz, R; Roig, I; Robles, P; Scherthan, H; Garcia Caldés, M

    2009-01-01

    Asynapsis of homologous chromosomes at the pachytene stage has been associated with gametogenic failure and infertility, but the cellular mechanisms involved are currently unknown in human meiocytes. In mice, the protein encoded by the breast-cancer susceptibility gene Brca1 has been described to direct kinase ATR (ataxia telangiectasia and Rad3 related) to any unpaired DNA at the pachytene stage, where ATR triggers H2AX phosphorylation, resulting in the silencing of those chromosomes. In this study, the distribution of ATR, BRCA1 and the phosphorylated histone gammaH2AX is assessed by immunofluorescence in human oocytes and it is found that they localize at unpaired chromosomes at the pachytene stage. Evidence is shown to propose that BRCA1, ATR and gammaH2AX in the human may be part of a system such as the one previously described in mouse, which signals unsynapsed chromosomes at pachytene and may lead to their silencing. PMID:19146767

  2. BRCA1 and FancJ cooperatively promote interstrand crosslinker induced centrosome amplification through the activation of polo-like kinase 1

    PubMed Central

    Zou, Jianqiu; Zhang, Deli; Qin, Guang; Chen, Xiangming; Wang, Hongmin; Zhang, Dong

    2014-01-01

    DNA damage response (DDR) and the centrosome cycle are 2 of the most critical cellular processes affecting the genome stability in animal cells. Yet the cross-talks between DDR and the centrosome are poorly understood. Here we showed that deficiency of the breast cancer 1, early onset gene (BRCA1) induces centrosome amplification in non-stressed cells as previously reported while attenuating DNA damage-induced centrosome amplification (DDICA) in cells experiencing prolonged genotoxic stress. Mechanistically, the function of BRCA1 in promoting DDICA is through binding and recruiting polo-like kinase 1 (PLK1) to the centrosome. In a recent study, we showed that FancJ also suppresses centrosome amplification in non-stressed cells while promoting DDICA in both hydroxyurea and mitomycin C treated cells. FancJ is a key component of the BRCA1 B-complex. Here, we further demonstrated that, in coordination with BRCA1, FancJ promotes DDICA by recruiting both BRCA1 and PLK1 to the centrosome in the DNA damaged cells. Thus, we have uncovered a novel role of BRCA1 and FancJ in the regulation of DDICA. Dysregulation of DDR or centrosome cycle leads to aneuploidy, which is frequently seen in both solid and hematological cancers. BRCA1 and FancJ are known tumor suppressors and have well-recognized functions in DNA damage checkpoint and DNA repair. Together with our recent findings, we demonstrated here that BRCA1 and FancJ also play an important role in centrosome cycle especially in DDICA. DDICA is thought to be an alternative fail-safe mechanism to prevent cells experiencing severe DNA damage from becoming carcinogenic. Therefore, BRCA1 and FancJ are potential liaisons linking early DDR with the DDICA. We propose that together with their functions in DDR, the role of BRCA1 and FancJ in the activation of DDICA is also crucial for their tumor suppression functions in vivo. PMID:25483079

  3. The basal-like mammary carcinomas induced by Brca1 or Bard1 inactivation implicate the BRCA1/BARD1 heterodimer in tumor suppression

    PubMed Central

    Shakya, Reena; Szabolcs, Matthias; McCarthy, Ellen; Ospina, Elson; Basso, Katia; Nandula, Subhadra; Murty, Vundavalli; Baer, Richard; Ludwig, Thomas

    2008-01-01

    Women with germ-line mutations of the BRCA1 tumor suppressor gene are highly susceptible to breast and ovarian cancer. The protein product of BRCA1 is involved in a broad spectrum of biological processes and interacts with many diverse proteins. One of these, BARD1, associates with BRCA1 to form a heterodimeric complex that is enzymatically active as an ubiquitin E3 ligase. Although the BRCA1/BARD1 heterodimer has been implicated in several aspects of BRCA1 function, its role in tumor suppression has not been evaluated. To address this question, we generated mouse strains carrying conditional alleles of either Bard1 or Brca1 and used Cre recombination to inactivate these genes in mammary epithelial cells. Significantly, the conditional Bard1- and Brca1-mutant mice developed breast carcinomas that are indistinguishable from each other (and from those of double conditional Bard1/Brca1-mutant animals) with respect to their frequency, latency, histopathology, and cytogenetic features. Reminiscent of the basal-like breast carcinomas seen in human BRCA1 mutation carriers, these tumors are “triple negative” for estrogen and progesterone receptor expression and HER2/neu amplification. They also express basal cytokeratins CK5 and CK14, have an elevated frequency of p53 lesions, and display high levels of chromosomal instability. The remarkable similarities between the mammary carcinomas of Bard1-, Brca1-, and Bard1/Brca1-mutant mice indicate that the tumor suppressor activities of both genes are mediated through the BRCA1/BARD1 heterodimer. PMID:18443292

  4. Targeting BRCA1 localization to augment breast tumor sensitivity to poly(ADP-ribose) polymerase inhibition

    PubMed Central

    Yang, Eddy S.; Nowsheen, Somaira; Rahman, Mohammad A.; Cook, Rebecca S.; Xia, Fen

    2013-01-01

    Poly(ADP-ribose) polymerase inhibitors have gained recent attention due to their highly selective killing of BRCA1/2 mutated and DNA double strand break (DSB) repair deficient tumors. Unfortunately, the majority of sporadic breast cancers carry wild-type BRCA1/2 and are proficient in DSB repair. We and others have shown that BRCA1 is a nuclear/cytoplasm shuttling protein which is transiently exported from the nucleus to the cytosol upon various stimuli. Thus, we hypothesized that depletion of nuclear BRCA1 would compromise DSB repair and subsequently render sporadic tumors susceptible to PARP inhibition. Indeed, in human sporadic breast cancer cells with functional BRCA1 and proficient DSB repair, a transient nuclear depletion of BRCA1 and subsequent HR repair deficit was induced with either truncated BRCA1 or irradiation. This rendered these human sporadic breast cancer cells susceptible to PARP inhibition. These observations were confirmed genetically using mislocated BRCA1 mutants as well as in vivo in mice bearing breast tumor xenografts. These data support the potential strategy of targeting BRCA1 location to convert BRCA1-proficient sporadic tumors to be susceptible to the synthetic lethal combination with PARP inhibitors. PMID:22962264

  5. THRA1 and D17S183 flank an interval of < 4 cM for the breast-ovarian cancer gene (BRCA1) on chromosome 17q21.

    PubMed Central

    Bowcock, A M; Anderson, L A; Friedman, L S; Black, D M; Osborne-Lawrence, S; Rowell, S E; Hall, J M; Solomon, E; King, M C

    1993-01-01

    In order to pinpoint the locale of the gene for early-onset familial breast and ovarian cancer (BRCA1), polymorphisms were developed within the locus for thyroid hormone receptor alpha (THRA1) and for several anonymous sequences at chromosome 17q12-q21. The THRA1 polymorphism is a dinucleotide repeat with 10 alleles and heterozygosity.79. Gene mapping in extended families with inherited, early-onset breast and ovarian cancer indicates that BRCA1 is distal to THRA1 and proximal to D17S183 (SCG43), an interval of < 4 cM. This locale excludes HER2, THRA1, WNT3, HOX2, NGFR, PHB, COLIA1, NME1, and NME2 as candidates for BRCA1 but does not exclude RARA or EDH17B. Resolving the remaining recombination events in these families by new polymorphisms in the THRA1-D17S183 interval will facilitate positional cloning of the breast-ovarian cancer gene on chromosome 17q12-q21. PMID:8460637

  6. THRA1 and D17S183 flank an interval of <4 cM for the breast-ovarian cancer gene (BRCA1) on chromosome 17q21

    SciTech Connect

    Bowcock, A.M.; Osborne-Lawrence, S. ); Anderson, L.A.; Friedman, L.S.; Rowell, S.E.; Hall, J.M.; King, M.C. ); Black, D.M.; Solomon, E. )

    1993-04-01

    In order to pinpoint the locale of the gene for early-onset familial breast and ovarian cancer (BRCA1), polymorphisms were developed within the locus for thyroid hormone receptor alpha (THRA1) and for several anonymous sequences at chromosome 17q12-q21. The THRA1 polymorphism is a dinucleotide repeat with 10 alleles and heterozygosity .79. Gene mapping in extended families with inherited, early-onset breast and ovarian cancer indicates that BRCA1 is distal to THRA1 and proximal to D17S183 (SCG43), an interval of <4 cM. This locale excludes HER2, THRA1, WNT3, HOX2, NGFR, PHB, COLIA1, NME1, and NME2 as candidates for BRCA1 but does not exclude RARA or EDH17B. Resolving the remaining recombination events in these families by new polymorphisms in the THRA1-D17S183 interval will facilitate positional cloning of the breast-ovarian cancer gene on chromosome 17q12-q21. 16 refs., 3 figs., 1 tab.

  7. Rare alleles of the HRAS polymorphism do not modify the risk of breast or ovarian cancer in BRCA1 carriers

    SciTech Connect

    Phelan, C.; Tonin, P.; Lynch, H.T.

    1994-09-01

    The presence of one of the rare alleles of a minisatellite polymorphism at the HRAS locus on chromosome 11p15 has been associated with a roughly two-fold increase in the risk of breast cancer. The BRCA1 gene on chromosome 17q12-21 is responsible for the majority of the families with the breast-ovarian cancer syndrome. It is estimated that 87% of BRCA1 carriers will be affected with breast cancer by age 70. The relative risk for premenopausal breast cancer in carriers, compared to non-carriers, is roughly 100. Because of the wide range in ages of onset of cancer among BRCA1 carriers, it is likely that additional factors modify the risk of cancer. The role of other modifying genetic loci has not been studied. Through haplotype analysis we have identified 199 female BRCA1 carriers above the age of 20 years in 25 linked families. 127 of these women have been diagnosed with cancer and 72 are currently healthy. DNA was available on 59 carriers. Each sample was typed for the HRAS polymorphism by PCR, using primers flanking the minisatellite. Rare alleles were identified in 18 carriers. The penetrance of the BRCA1 gene was not higher among those women who carried a rare HRAS allele (mean age of onset 49 years) than among those who carried two common alleles (mean age of onset 43 years) (p= 0.59; log rank test). Similar results were obtained for ovarian cancer. These data do not support the hypothesis that the HRAS locus modified the risk of cancer among carriers of mutations in BRCA1.

  8. Transgenic expression of BRCA1 disturbs hematopoietic stem and progenitor cells quiescence and function

    SciTech Connect

    Bai, Lin; Shi, Guiying; Zhang, Xu; Dong, Wei; Zhang, Lianfeng

    2013-10-15

    The balance between quiescence and proliferation of HSCs is an important regulator of hematopoiesis. Loss of quiescence frequently results in HSCs exhaustion, which underscores the importance of tight regulation of proliferation in these cells. Studies have indicated that cyclin-dependent kinases are involved in the regulation of quiescence in HSCs. BRCA1 plays an important role in the repair of DNA double-stranded breaks, cell cycle, apoptosis and transcription. BRCA1 is expressed in the bone marrow. However, the function of BRCA1 in HSCs is unknown. In our study, we generated BRCA1 transgenic mice to investigate the effects of BRCA1 on the mechanisms of quiescence and differentiation in HSCs. The results demonstrate that over-expression of BRCA1 in the bone marrow impairs the development of B lymphocytes. Furthermore, BRCA1 induced an increase in the number of LSKs, LT-HSCs, ST-HSCs and MPPs. A competitive transplantation assay found that BRCA1 transgenic mice failed to reconstitute hematopoiesis. Moreover, BRCA1 regulates the expression of p21{sup waf1}/cip1 and p57{sup kip2}, which results in a loss of quiescence in LSKs. Together, over-expression of BRCA1 in bone marrow disrupted the quiescent of LSKs, induced excessive accumulation of LSKs, and disrupted differentiation of the HSCs, which acts through the down-regulated of p21{sup waf1}/cip1 and p57{sup kip2}. - Highlights: • Over-expression of BRCA1 results in impaired B lymphocyte development. • BRCA1 transgenic mice disrupted the quiescent of LSKs, induced excessive accumulation of LSKs. • BRCA1 impairs the function of HSCs through the down-regulated of p21{sup waf1/cip1} and p57{sup kip2}.

  9. BRCA1 involved in regulation of Bcl-2 expression and apoptosis susceptibility to ionizing radiation

    NASA Astrophysics Data System (ADS)

    Wang, YanLing; Wang, Bing; Zhang, Hong; Li, Ning; Tanaka, Kaoru; Zhou, Xin; Chen, RuPing; Zhang, Xin

    2011-05-01

    BRCA1 has been proposed to be tightly linked to the resistance of tumor cells to ionizing radiation. The pathway leading to this phenomenon is not yet clear. In this work, we investigated the role of BRCA1 in the apoptosis regulation in response to carbon ion irradiation. We utilized three different cancer cell lines with various states for BRCA1 and p53 to identify the relationship between endogenous BRCA1 and the apoptosis-related genes, and determine whether p53 function would affect the role of BRCA1 in apoptosis regulation. By Western blot analysis, we found that Bax expressions were not significantly changed after irradiation in all of three cell lines. However, Bcl-2 expression showed an up-regulation by endogenous BRCA1 regardless of p53 status. Moreover, the changes in Bcl-2 protein were due to the increase in the transcriptional levels of Bcl-2 mRNA, based on real-time PCR assay. At the same time, BRCA1-deficient cells showed a greater apoptosis susceptibility to irradiation when compared with BRCA1-proficient cells. The results suggest that BRCA1 might exert p53-independent regulative activities for Bcl-2, which seems account for the low apoptosis susceptibility in BRCA1-proficient carcinomas.

  10. Detection of novel germline mutations for breast cancer in non-BRCA1/2 families.

    PubMed

    Aloraifi, Fatima; McDevitt, Trudi; Martiniano, Rui; McGreevy, Jonah; McLaughlin, Russell; Egan, Chris M; Cody, Nuala; Meany, Marie; Kenny, Elaine; Green, Andrew J; Bradley, Daniel G; Geraghty, James G; Bracken, Adrian P

    2015-09-01

    The identification of the breast cancer susceptibility genes BRCA1 and BRCA2 enhanced clinicians' ability to select high-risk individuals for aggressive surveillance and prevention, and led to the development of targeted therapies. However, BRCA1/2 mutations account for only 25% of familial breast cancer cases. To systematically identify rare, probably pathogenic variants in familial cases of breast cancer without BRCA1/2 mutations, we developed a list of 312 genes, and performed targeted DNA enrichment coupled to multiplex next-generation sequencing on 104 'BRCAx' patients and 101 geographically matched controls in Ireland. As expected, this strategy allowed us to identify mutations in several well-known high-susceptibility and moderate-susceptibility genes, including ATM (~ 5%), RAD50 (~ 3%), CHEK2 (~ 2%), TP53 (~ 1%), PALB2 (~ 1%), and MRE11A (~ 1%). However, we also identified novel pathogenic variants in 30 other genes, which, when taken together, potentially explain the etiology of the missing heritability in up to 35% of BRCAx patients. These included novel potential pathogenic mutations in MAP3K1, CASP8, RAD51B, ZNF217, CDKN2B-AS1, and ERBB2, including a splice site mutation, which we predict would generate a constitutively active HER2 protein. Taken together, this work extends our understanding of the genetics of familial breast cancer, and supports the need to implement hereditary multigene panel testing to more appropriately orientate clinical management. PMID:26094658

  11. Germline BRCA1 mutations increase prostate cancer risk

    PubMed Central

    Leongamornlert, D; Mahmud, N; Tymrakiewicz, M; Saunders, E; Dadaev, T; Castro, E; Goh, C; Govindasami, K; Guy, M; O'Brien, L; Sawyer, E; Hall, A; Wilkinson, R; Easton, D; Goldgar, D; Eeles, R; Kote-Jarai, Z

    2012-01-01

    Background: Prostate cancer (PrCa) is one of the most common cancers affecting men but its aetiology is poorly understood. Family history of PrCa, particularly at a young age, is a strong risk factor. There have been previous reports of increased PrCa risk in male BRCA1 mutation carriers in female breast cancer families, but there is a controversy as to whether this risk is substantiated. We sought to evaluate the role of germline BRCA1 mutations in PrCa predisposition by performing a candidate gene study in a large UK population sample set. Methods: We screened 913 cases aged 36–86 years for germline BRCA1 mutation, with the study enriched for cases with an early age of onset. We analysed the entire coding region of the BRCA1 gene using Sanger sequencing. Multiplex ligation-dependent probe amplification was also used to assess the frequency of large rearrangements in 460 cases. Results: We identified 4 deleterious mutations and 45 unclassified variants (UV). The frequency of deleterious BRCA1 mutation in this study is 0.45% three of the mutation carriers were affected at age ⩽65 years and one developed PrCa at 69 years. Using previously estimated population carrier frequencies, deleterious BRCA1 mutations confer a relative risk of PrCa of ∼3.75-fold, (95% confidence interval 1.02–9.6) translating to a 8.6% cumulative risk by age 65. Conclusion This study shows evidence for an increased risk of PrCa in men who harbour germline mutations in BRCA1. This could have a significant impact on possible screening strategies and targeted treatments. PMID:22516946

  12. Cardiovascular risk of BRCA1/2 mutation carriers: A review.

    PubMed

    van Westerop, L L M; Arts-de Jong, M; Hoogerbrugge, N; de Hullu, J A; Maas, A H E M

    2016-09-01

    BRCA1/2 mutation carriers are at high risk of breast and ovarian cancer. The number of studies on non-cancer endpoints in BRCA1/2 mutation carriers is still limited. BRCA1/2 mutation carriers may be at higher cardiovascular risk due to early menopause after risk-reducing salpingo-oophorectomy and/or due to the potential cardiotoxic effects of breast cancer treatment (radiotherapy and chemotherapy). Moreover, BRCA genes have a role as a gatekeeper in cardiac function and structure, which may affect susceptibility to cardiac damage. Our goal is to review current knowledge of cardiovascular risk among BRCA1/2 mutation carriers. PMID:27451331

  13. A recessive variant of XRCC4 predisposes to non-BRCA1/2 breast cancer in chinese women and impairs the DNA damage response via dysregulated nuclear localization

    PubMed Central

    He, Min; Hu, Xin; Chen, Li; Cao, A-Yong; Yu, Ke-Da; Shi, Ting-Yan; Kuang, Xia-Ying; Shi, Wen-Biao; Ling, Hong; Li, Shan; Qiao, Feng; Yao, Ling; Wei, Qingyi; Di, Gen-Hong; Shao, Zhi-Ming

    2014-01-01

    XRCC4 plays a crucial role in the non-homologous end joining pathway that maintains genome stability. In this two-stage case-control study with 1,764 non-BRCA1/2 breast cancer patients and 1,623 cancer-free controls, we investigated the contribution of genetic variants of XRCC4 to breast cancer susceptibility in Chinese women. We identified a recessive missense variant, rs3734091 (c.739G>T, p.Ala247Ser), of XRCC4 that was significantly associated with an increased risk of breast cancer (odds ratio [OR] = 3.92, P = 0.007), particularly with the risk of developing triple-negative breast cancer (OR = 18.65, P < 0.0001). This p.Ala247Ser variant disturbed the nuclear localization of XRCC4 in cells homozygous for the rs3734091-T allele but not in heterozygous cells at both the cellular and tissue levels. In heterozygous cells, wild-type XRCC4 facilitated the nuclear localization of the XRCC4A247S mutant, thus compensating for the impaired localization of XRCC4A247S. This provided a biological mechanism by which rs3734091 conferred an increased susceptibility to non-BRCA1/2 breast cancer exclusively under a recessive model. Further functional analyses revealed that p.Ala247Ser impaired the DNA damage repair capacity and ultimately perturbed genomic stability. Taken together, our findings document the role of XRCC4 in non-BRCA1/2 breast cancer predisposition and reveal its underlying biological mechanism of action. PMID:25360583

  14. Analysis of Induced Pluripotent Stem Cells from a BRCA1 Mutant Family

    PubMed Central

    Soyombo, Abigail A.; Wu, Yipin; Kolski, Lauren; Rios, Jonathan J.; Rakheja, Dinesh; Chen, Alice; Kehler, James; Hampel, Heather; Coughran, Alanna; Ross, Theodora S.

    2013-01-01

    Summary Understanding BRCA1 mutant cancers is hampered by difficulties in obtaining primary cells from patients. We therefore generated and characterized 24 induced pluripotent stem cell (iPSC) lines from fibroblasts of eight individuals from a BRCA1 5382insC mutant family. All BRCA1 5382insC heterozygous fibroblasts, iPSCs, and teratomas maintained equivalent expression of both wild-type and mutant BRCA1 transcripts. Although no difference in differentiation capacity was observed between BRCA1 wild-type and mutant iPSCs, there was elevated protein kinase C-theta (PKC-theta) in BRCA1 mutant iPSCs. Cancer cell lines with BRCA1 mutations and hormone-receptor-negative breast cancers also displayed elevated PKC-theta. Genome sequencing of the 24 iPSC lines showed a similar frequency of reprogramming-associated de novo mutations in BRCA1 mutant and wild-type iPSCs. These data indicate that iPSC lines can be derived from BRCA1 mutant fibroblasts to study the effects of the mutation on gene expression and genome stability. PMID:24319668

  15. The putative oncogene CEP72 inhibits the mitotic function of BRCA1 and induces chromosomal instability.

    PubMed

    Lüddecke, S; Ertych, N; Stenzinger, A; Weichert, W; Beissbarth, T; Dyczkowski, J; Gaedcke, J; Valerius, O; Braus, G H; Kschischo, M; Bastians, H

    2016-05-01

    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. PMID:26300001

  16. BRCA1--sowing the seeds crooked in the furrow.

    PubMed

    Foulkes, William D

    2008-01-01

    Breast tumors with deficiency in DNA double-strand break repair might be expected to show aneuploidy. A new study shows that microdeletions in PTEN, resulting in complete loss of PTEN protein, are signature lesions in these cancers, particularly those arising in BRCA1-mutation carriers. PMID:18163127

  17. Multimodal Assessment of Protein Functional Deficiency Supports Pathogenicity of BRCA1 p.V1688del

    PubMed Central

    De Nicolo, Arcangela; Parisini, Emilio; Zhong, Quan; Palma, Maurizia Dalla; Stoeckert, Kathryn A.; Domchek, Susan M.; Nathanson, Katherine L.; Caligo, Maria A.; Vidal, Marc; Cusick, Michael E.; Garber, Judy E.

    2009-01-01

    Unequivocal discrimination between neutral variants and deleterious mutations is crucial for appropriate counseling of individuals with a BRCA1 or BRCA2 sequence change. An increasing number of variants of uncertain significance (VUSs) are being identified, whose unclassified biological effect poses clinical concerns. A multifactorial likelihood-based approach recently suggested disease causality for BRCA1 p.V1688del, a VUS recurrent in Italian breast/ovarian cancer families. Whether and how this single amino acid deletion in the BRCA1 BRCT domain affects the function of the mutant protein (ΔValBRCA1) has not been elucidated. We undertook comprehensive functional characterization of ΔValBRCA1, comprising comparative structural modeling, analysis of protein stability and associations, and analysis of DNA repair function. Our model predicted BRCT domain destabilization and folding disruption caused by BRCA1 p.V1688del. Consistently, the recombinant ΔValBRCA1 was less stable than wtBRCA1 and, unlike the latter, failed to associate with BRIP1, CtIP, and Rap80, and to re-localize to sites of DNA damage. Yeast two-hybrid analysis revealed a compromised interaction with FHL2 and with KPNA2, which is likely responsible for improper subcellular localization of ΔValBRCA1. In addition, we found four new breast/ovarian cancer families of Italian ancestry who carried this sequence alteration. These results provide the first evidence of the effect of BRCA1 p.V1688del on protein stability and function, supporting the view that it is a deleterious mutation. Multimodal analyses like ours could advance understanding of tumor suppression by BRCA1, and ultimately contribute to developing efficient strategies for screening and characterization of VUSs. PMID:19706752

  18. Attitudes and distress levels in women at risk to carry a BRCA1/BRCA2 gene mutation who decline genetic testing.

    PubMed

    Lodder, Litanja; Frets, Petra G; Trijsburg, R Willem; Klijn, Jan G M; Seynaeve, Caroline; Tilanus, Madeleine M A; Bartels, Carina C M; Meijers-Heijboer, E Johanna; Verhoog, Leon C; Niermeijer, Martinus F

    2003-06-15

    Genetic testing enables women at risk for hereditary breast and/or ovarian cancer to find out whether they have inherited the gene mutation, and if so, to opt for undergoing frequent surveillance and/or prophylactic surgery. However, the option to know about one's genetic status is not always seen as a benefit by women at risk. Motives for declining genetic testing were explored in 13 women at 25% or 50% risk to be a BRCA1/BRCA2 mutation carrier, who participated in a surveillance program for breast/ovarian cancer (the non-tested group). We hypothesized that high anxiety might be an important motive to decline testing. In addition, we investigated whether the non-tested group differed from a reference group of women who did undergo the test (tested group; n = 85) with regard to biographical factors, experience with cancer in relatives, and personality traits. Most non-tested women (10/13) were satisfied with participating in the surveillance program. Four reported to feel emotionally unprepared to cope with the consequences of testing. Compared with the tested group, the non-tested women had similar mean distress levels (which were not high), but a higher education level, they were more often childless, showed more reluctance towards prophylactic surgery, were younger when first confronted with a relative affected with breast/ovarian cancer, and were longer aware of the genetic nature of the disease. This study showed that women were more likely to have thoroughly reflected on their decision not to undergo genetic testing, than to deny the whole issue due to high anxiety. Being confronted at a relatively young age with breast/ovarian cancer in a relative, and being aware of the genetic risk for a many years, may have resulted in the risk for cancer becoming an integrated part of their lives. However, generalization of these results to women who neither underwent the test nor participated in a surveillance program should be considered with caution. PMID:12784290

  19. Downregulation of BRCA1-BRCA2-containing complex subunit 3 sensitizes glioma cells to temozolomide.

    PubMed

    Chai, Kit Man; Wang, Chih-Yen; Liaw, Hung-Jiun; Fang, Kuan-Min; Yang, Chung-Shi; Tzeng, Shun-Fen

    2014-11-15

    We previously found that BRCA1-BRCA2-containing complex subunit 3 (BRCC3) was highly expressed in tumorigenic rat glioma cells. However, the functional role of BRCC3 in human glioma cells remains to be characterized. This study indicated that the upregulation of BRCC3 expression was induced in two human malignant glioblastoma U251 and A172 cell lines following exposure to the alkylating agent, temozolomide (TMZ). Homologous recombination (HR)-dependent DNA repair-associated genes (i.e. BRCA1, BRCA2, RAD51 and FANCD2) were also increased in U251 and A172 cells after treatment with TMZ. BRCC3 gene knockdown through lentivirus-mediated gene knockdown approach not only significantly reduced the clonogenic and migratory abilities of U251 and A172 cells, but also enhanced their sensitization to TMZ. The increase in phosphorylated H2AX foci (γH2AX) formation, an indicator of DNA damage, persisted in TMZ-treated glioma cells with stable knockdown BRCC3 expression, suggesting that BRCC3 gene deficiency is associated with DNA repair impairment. In summary, we demonstrate that by inducing DNA repair, BRCC3 renders glioma cells resistant to TMZ. The findings point to BRCC3 as a potential target for treatment of alkylating drug-resistant glioma. PMID:25337721

  20. Breast and ovarian cancer predisposition due to de novo BRCA1 and BRCA2 mutations.

    PubMed

    Golmard, L; Delnatte, C; Laugé, A; Moncoutier, V; Lefol, C; Abidallah, K; Tenreiro, H; Copigny, F; Giraudeau, M; Guy, C; Barbaroux, C; Amorim, G; Briaux, A; Guibert, V; Tarabeux, J; Caputo, S; Collet, A; Gesta, P; Ingster, O; Stern, M-H; Rouleau, E; de Pauw, A; Gauthier-Villars, M; Buecher, B; Bézieau, S; Stoppa-Lyonnet, D; Houdayer, C

    2016-03-10

    BRCA1 and BRCA2 are the two major genes predisposing to breast and ovarian cancer. Whereas high de novo mutation rates have been demonstrated for several genes, only 11 cases of de novo BRCA1/2 mutations have been reported to date and the BRCA1/2 de novo mutation rate remains unknown. The present study was designed to fill this gap based on a series of 12 805 consecutive unrelated patients diagnosed with breast and/or ovarian cancer who met the inclusion criteria for BRCA1/2 gene analysis according to French guidelines. BRCA1/2 mutations were detected in 1527 (12%) patients, and three BRCA1 mutations and one BRCA2 mutation were de novo. The BRCA1/2 de novo mutation rate was estimated to be 0.3% (0.1%; 0.7%). Although rare, it may be useful to take the possibility of de novo BRCA1/2 mutation into account in genetic counseling of relatives and to improve the understanding of complex family histories of breast and ovarian cancers. PMID:26028024

  1. Cell cycle-dependent colocalization of BARD1 and BRCA1 proteins in discrete nuclear domains

    PubMed Central

    Jin, Ying; Xu, Xie L.; Yang, Meng-Chun W.; Wei, Fanglin; Ayi, Teck-Choon; Bowcock, Anne M.; Baer, Richard

    1997-01-01

    Germ-line mutations of the BRCA1 gene predispose women to early-onset breast and ovarian cancer by compromising the gene’s presumptive function as a tumor suppressor. Although the biochemical properties of BRCA1 polypeptides are not understood, their expression pattern and subcellular localization suggest a role in cell-cycle regulation. When resting cells are induced to proliferate, the steady-state levels of BRCA1 increase in late G1 and reach a maximum during S phase. Moreover, in S phase cells, BRCA1 polypeptides are hyperphosphorylated and accumulate into discrete subnuclear foci termed “BRCA1 nuclear dots.” BRCA1 associates in vivo with a structurally related protein termed BARD1. Here we show that the steady-state levels of BARD1, unlike those of BRCA1, remain relatively constant during cell cycle progression. However, immunostaining revealed that BARD1 resides within BRCA1 nuclear dots during S phase of the cell cycle, but not during the G1 phase. Nevertheless, BARD1 polypeptides are found exclusively in the nuclear fractions of both G1- and S-phase cells. Therefore, progression to S phase is accompanied by the aggregation of nuclear BARD1 polypeptides into BRCA1 nuclear dots. This cell cycle-dependent colocalization of BARD1 and BRCA1 indicates a role for BARD1 in BRCA1-mediated tumor suppression. PMID:9342365

  2. Constitutive activation of the ATM/BRCA1 pathway prevents DNA damage-induced apoptosis in 5-azacytidine-resistant cell lines.

    PubMed

    Imanishi, Satoshi; Umezu, Tomohiro; Ohtsuki, Kazushige; Kobayashi, Chiaki; Ohyashiki, Kazuma; Ohyashiki, Junko H

    2014-06-01

    5-Azacytidine (AZA) exerts its anti-tumor effects by exerting cytotoxicity via its incorporation into RNA and DNA, which causes the reactivation of aberrantly silenced growth-regulatory genes by promoter demethylation, as well as DNA damage. AZA is used for patients with myelodysplastic syndrome and acute myeloid leukemia. However, some patients demonstrate resistance to AZA, the mechanisms of which are not fully elucidated. We therefore sought to better characterize the molecular mechanism of AZA resistance using an in vitro model of AZA resistance. We established AZA-resistant cell lines by exposing the human leukemia cell lines U937 and HL-60 to clinical concentrations of AZA, and characterized these cells. AZA-resistant cells showed a down-regulation of the DNMT3A protein, in correlation with their marked genome-wide DNA hypomethylation. Furthermore, genes involved in pyrimidine metabolism were down-regulated in both AZA-resistant cell lines; AZA sensitivity was restored by inhibition of CTP synthase. Of note is that the DNA damage response pathway is constitutively activated in the AZA-resistant cell lines, but not in the parental cell lines. Inhibition of the DNA damage response pathway canceled the AZA resistance, in association with an increase in apoptotic cells. We found that the molecular mechanism underlying AZA resistance involves pyrimidine metabolism and the DNA damage response through ATM kinase. This study therefore sheds light on the mechanisms underlying AZA resistance, and will enable better understanding of AZA resistance in patients undergoing AZA treatment. PMID:24680865

  3. Loss of BRCA1-A Complex Function in RAP80 Null Tumor Cells

    PubMed Central

    Cho, Kathleen; Yu, Xiaochun

    2012-01-01

    Receptor Associated Protein 80 (RAP80) is a subunit of the BRCA1-A complex and targets BRCA1 to DNA damage sites in response to DNA double strand breaks. Since mutations of BRCA1 are associated with familial ovarian cancers, we screened 26 ovarian cancer-derived cell lines for RAP80 mutations and found that TOV-21G cells harbor a RAP80 mutation (c.1107G >A). This mutation generates a stop codon at Trp369, which deletes the partial AIR region and the C-terminal zinc fingers of RAP80. Interestingly, both the mutant and wild type alleles of RAP80 lose their expression due to promoter hypermethylation, suggesting that TOV-21G is a RAP80-null cell line. In these cells, not only is the BRCA1-A complex disrupted, but the relocation of the remaining subunits in the BRCA1-A complex including BRCA1, CCDC98, NBA1, BRCC36 and BRE is significantly suppressed. Moreover, TOV-21G cells are hypersensitive to ionizing radiation, which is due to the compromised DNA damage repair capacity in these cells. Reconstitution of TOV-21G cells with wild type RAP80 rescues these cellular defects in response to DNA damage. Thus, our results demonstrate that RAP80 is a scaffold protein in the BRCA1-A complex. Identification of TOV-21G as a RAP80 null tumor cell line will be very useful for the study of the molecular mechanism in DNA damage response. PMID:22792303

  4. ENIGMA--evidence-based network for the interpretation of germline mutant alleles: an international initiative to evaluate risk and clinical significance associated with sequence variation in BRCA1 and BRCA2 genes.

    PubMed

    Spurdle, Amanda B; Healey, Sue; Devereau, Andrew; Hogervorst, Frans B L; Monteiro, Alvaro N A; Nathanson, Katherine L; Radice, Paolo; Stoppa-Lyonnet, Dominique; Tavtigian, Sean; Wappenschmidt, Barbara; Couch, Fergus J; Goldgar, David E

    2012-01-01

    As genetic testing for predisposition to human diseases has become an increasingly common practice in medicine, the need for clear interpretation of the test results is apparent. However, for many disease genes, including the breast cancer susceptibility genes BRCA1 and BRCA2, a significant fraction of tests results in the detection of a genetic variant for which disease association is not known. The finding of an "unclassified" variant (UV)/variant of uncertain significance (VUS) complicates genetic test reporting and counseling. As these variants are individually rare, a large collaboration of researchers and clinicians will facilitate studies to assess their association with cancer predisposition. It was with this in mind that the ENIGMA consortium (www.enigmaconsortium.org) was initiated in 2009. The membership is both international and interdisciplinary, and currently includes more than 100 research scientists and clinicians from 19 countries. Within ENIGMA, there are presently six working groups focused on the following topics: analysis, clinical, database, functional, tumor histopathology, and mRNA splicing. ENIGMA provides a mechanism to pool resources, exchange methods and data, and coordinately develop and apply algorithms for classification of variants in BRCA1 and BRCA2. It is envisaged that the research and clinical application of models developed by ENIGMA will be relevant to the interpretation of sequence variants in other disease genes. PMID:21990146

  5. Screening for Del 185 AG and 4627C>A BRCA1 Mutations in Breast Cancer Patients from Lahore, Pakistan.

    PubMed

    Aziz, Faiza; Fatima, Warda; Mahmood, Saqib; Khokher, Samina

    2016-01-01

    Breast cancer contributes to approximately 23% of the cancer cases identified and 14% of cancer related deaths worldwide. Including a strong association between genetic and environmental factors, breast cancer is a complex and multi factorial disorder. Two high penetration breast cancer susceptibility genes (BRCA1 and BRCA2) have been identified, and germ line mutations in these are thought to account for between 5% and 10% of all breast cancer cases. The human BRCA1 gene, located on 17q, is involved in the regulation of cell proliferation by aiding in DNA repair, transcriptional responses to DNA damage and cell cycle check points. Mutations in this gene enhance cell proliferation and facilitate formation of tumors. Two mutations, the 185 deletion of AG and the 4627 substitution from C to A, are founder mutations in the BRCA1 gene for breast cancer in Asian populations. Allele specific PCR was performed to detect these selected mutations in 120 samples. No mutation of 4627 C to A was detected in the samples and only one of the patients had the 185 del AG mutation in the heterozygous condition. Our collected samples had lower consanguinity and family history indicating the greater involvement of environmental as compared to genetic factors. PMID:27221844

  6. BRCA1 and BRCA2 mutations in Iranian breast cancer patients: A systematic review

    PubMed Central

    Neamatzadeh, Hossein; Shiryazdi, Seyed Mostafa; Kalantar, Seyed Mahdi

    2015-01-01

    Background: BRCA1/2 genes mutation prevalence varies among ethnic groups and may be influenced by founder mutations. Understanding BRCA1/2 genes mutations is important for reducing breast cancer (BC) incidence, accurate risk assessment and counseling. This systematic review of the literature was conducted to addressing BRCA1/2 mutations in Iranian BC patients. Materials and Methods: A search for relevant articles was run on before January 2014 using MedLine, PubMed, Science Iranian Database, Google, and Web sites related to the study topic. The key words included: BC and Iran with Genes, BRCA Genes, BRCA1 and BRCA2; “Cancer Genes,” and “Iran.” Results: Thirteen articles retrieved from this search strategy were eligible for this review. The overall BRCA1 mutation rate for Iranian female BC patients was detected 31.8% (377/1183). Although this gene mutation rate for male patients is <0.01%. Eight BRCA1 mutations (c. 4837A > G, c. 3419G > A, c. 3119G > A, c. 2612C > T, c. 3113A > G, c. 2311T > C, c. 4301T > C and c. 4308T > C in BRCA1, and one BRCA2 mutation (c. 6494G > C) were found in multiple case subjects and represent candidate founder mutations. Conclusion: According to these studies, there is heterogeneity in BRCA mutations in Iranian BC patients. PMID:26109977

  7. Copy number variations are not modifiers of phenotypic expression in a pair of identical twins carrying a BRCA1 mutation.

    PubMed

    Lasa, A; Ramón y Cajal, T; Llort, G; Suela, J; Cigudosa, J C; Cornet, M; Alonso, C; Barnadas, A; Baiget, M

    2010-10-01

    Mutations in BRCA1 and BRCA2 genes confer a high risk of breast and ovarian cancer but the incomplete penetrance of these mutations suggests that other genetic and/or environmental factors may modify this risk. We present a family where all affected members carried a mutation in the BRCA1 gene and the index case had suffered from cancer twice in the last 27 years, whereas her monozygotic twin sister, also a carrier of the mutation, remained healthy. As copy number variants (CNVs) contribute to phenotypic diversity, a comparative genomic hybridization array (CGH) was performed to see whether the differences in the CNV profile were a modifier factor of the phenotype in our monozygotic twins. Our results show that differences in the CNVs profile were not the cause of the extremely variable penetrance observed in our MZ twin. The search for an explanation should not therefore be limited to genetic changes at the level of the DNA sequence. PMID:20369283

  8. Prevalence of BRCA1 Mutations in Familial and Sporadic Greek Ovarian Cancer Cases

    PubMed Central

    Stavropoulou, Alexandra V.; Fostira, Florentia; Pertesi, Maroulio; Tsitlaidou, Marianthi; Voutsinas, Gerassimos E.; Triantafyllidou, Olga; Bamias, Aristotelis; Dimopoulos, Meletios A.; Timotheadou, Eleni; Pectasides, Dimitrios; Christodoulou, Christos; Klouvas, George; Papadimitriou, Christos; Makatsoris, Thomas; Pentheroudakis, George; Aravantinos, Gerasimos; Karydakis, Vassilis; Yannoukakos, Drakoulis; Fountzilas, George; Konstantopoulou, Irene

    2013-01-01

    Germline mutations in the BRCA1 and BRCA2 genes contribute to approximately 18% of hereditary ovarian cancers conferring an estimated lifetime risk from 15% to 50%. A variable incidence of mutations has been reported for these genes in ovarian cancer cases from different populations. In Greece, six mutations in BRCA1 account for 63% of all mutations detected in both BRCA1 and BRCA2 genes. This study aimed to determine the prevalence of BRCA1 mutations in a Greek cohort of 106 familial ovarian cancer patients that had strong family history or metachronous breast cancer and 592 sporadic ovarian cancer cases. All 698 patients were screened for the six recurrent Greek mutations (including founder mutations c.5266dupC, p.G1738R and the three large deletions of exon 20, exons 23–24 and exon 24). In familial cases, the BRCA1 gene was consequently screened for exons 5, 11, 12, 20, 21, 22, 23, 24. A deleterious BRCA1 mutation was found in 43/106 (40.6%) of familial cancer cases and in 27/592 (4.6%) of sporadic cases. The variant of unknown clinical significance p.V1833M was identified in 9/698 patients (1.3%). The majority of BRCA1 carriers (71.2%) presented a high-grade serous phenotype. Identifying a mutation in the BRCA1 gene among breast and/or ovarian cancer families is important, as it enables carriers to take preventive measures. All ovarian cancer patients with a serous phenotype should be considered for genetic testing. Further studies are warranted to determine the prevalence of mutations in the rest of the BRCA1 gene, in the BRCA2 gene, and other novel predisposing genes for breast and ovarian cancer. PMID:23536787

  9. CtIP-mediated resection is essential for viability and can operate independently of BRCA1.

    PubMed

    Polato, Federica; Callen, Elsa; Wong, Nancy; Faryabi, Robert; Bunting, Samuel; Chen, Hua-Tang; Kozak, Marina; Kruhlak, Michael J; Reczek, Colleen R; Lee, Wen-Hwa; Ludwig, Thomas; Baer, Richard; Feigenbaum, Lionel; Jackson, Stephen; Nussenzweig, André

    2014-06-01

    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. PMID:24842372

  10. The Effectiveness of Cucurbitacin B in BRCA1 Defective Breast Cancer Cells

    PubMed Central

    Chakrabarty, Subhas; Bögler, Oliver; Patmasiriwat, Pimpicha

    2013-01-01

    Cucurbitacin B (CuB) is one of the potential agents for long term anticancer chemoprevention. Cumulative evidences has shown that cucurbitacin B provides potent cellular biological activities such as hepatoprotective, anti-inflammatory and antimicrobial effects, but the precise mechanism of this agent is not clearly understood. We examine the biological effects on cancer cells of cucurbitacin B extracted from a Thai herb, Trichosanthes cucumerina L. The wild type (wt) BRCA1, mutant BRCA1, BRCA1 knocked-down and BRCA1 overexpressed breast cancer cells were treated with the cucurbitacin B and determined for the inhibitory effects on the cell proliferation, migration, invasion, anchorage-independent growth. The gene expressions in the treated cells were analyzed for p21/Waf1, p27Kip1 and survivin. Our previous study revealed that loss of BRCA1 expression leads to an increase in survivin expression, which is responsible for a reduction in sensitivity to paclitaxel. In this work, we showed that cucurbitacin B obviously inhibited knocked-down and mutant BRCA1 breast cancer cells rather than the wild type BRCA1 breast cancer cells in regards to the cellular proliferation, migration, invasion and anchorage-independent growth. Furthermore, forcing the cells to overexpress wild type BRCA1 significantly reduced effectiveness of cucurbitacin B on growth inhibition of the endogenous mutant BRCA1 cells. Interestingly, cucurbitacin B promotes the expression of p21/Waf1 and p27Kip1 but inhibit the expression of survivin. We suggest that survivin could be an important target of cucurbitacin B in BRCA1 defective breast cancer cells. PMID:23393598

  11. Association of BRCA1 promoter methylation with sporadic breast cancers: Evidence from 40 studies.

    PubMed

    Zhang, Li; Long, Xinghua

    2015-01-01

    Breast cancer susceptibility gene 1 (BRCA1) located at chromosome 17q12-21 is a classic tumor suppressor gene, and has been considered as a significant role in hereditary breast cancers. Moreover, numerous studies demonstrated the methylation status of CpG islands in the promoter regions of BRCA1 gene was aberrant in patients with sporadic breast tumors compared with healthy females or patients with benign diseases. However, these conclusions were not always consistent. Hence, a meta-analysis was performed to get a more precise estimate for these associations. Crude odds ratio with 95% confidence interval were used to assess the association of BRCA1 promoter methylation and the risk or clinicopathologic characteristics of breast cancers under fixed or random effect model. A total of 40 studies were eligible for this present study. We observed the frequency of BRCA1 promoter methylation was statistically significant higher in breast cancers than non-cancer controls. Furthermore, BRCA1 methylation was statistically associated with lymph node metastasis, histological grade 3, ER(-), PR(-), triple-negative phenotype, and decreased or lack levels of BRCA1 protein expression. In conclusion, this study indicated that BRCA1 promoter methylation appeared to be a useful predictive or prognostic biomarker for breast cancers in clinical assessment. PMID:26643130

  12. Association of BRCA1 promoter methylation with sporadic breast cancers: Evidence from 40 studies

    PubMed Central

    Zhang, Li; Long, Xinghua

    2015-01-01

    Breast cancer susceptibility gene 1 (BRCA1) located at chromosome 17q12-21 is a classic tumor suppressor gene, and has been considered as a significant role in hereditary breast cancers. Moreover, numerous studies demonstrated the methylation status of CpG islands in the promoter regions of BRCA1 gene was aberrant in patients with sporadic breast tumors compared with healthy females or patients with benign diseases. However, these conclusions were not always consistent. Hence, a meta-analysis was performed to get a more precise estimate for these associations. Crude odds ratio with 95% confidence interval were used to assess the association of BRCA1 promoter methylation and the risk or clinicopathologic characteristics of breast cancers under fixed or random effect model. A total of 40 studies were eligible for this present study. We observed the frequency of BRCA1 promoter methylation was statistically significant higher in breast cancers than non-cancer controls. Furthermore, BRCA1 methylation was statistically associated with lymph node metastasis, histological grade 3, ER(-), PR(-), triple-negative phenotype, and decreased or lack levels of BRCA1 protein expression. In conclusion, this study indicated that BRCA1 promoter methylation appeared to be a useful predictive or prognostic biomarker for breast cancers in clinical assessment. PMID:26643130

  13. Targeting BRCA1- and BRCA2-deficient cells with RAD52 small molecule inhibitors

    PubMed Central

    Huang, Fei; Goyal, Nadish; Sullivan, Katherine; Hanamshet, Kritika; Patel, Mikir; Mazina, Olga M.; Wang, Charles X.; An, W. Frank; Spoonamore, James; Metkar, Shailesh; Emmitte, Kyle A.; Cocklin, Simon; Skorski, Tomasz; Mazin, Alexander V.

    2016-01-01

    RAD52 is a member of the homologous recombination (HR) pathway that is important for maintenance of genome integrity. While single RAD52 mutations show no significant phenotype in mammals, their combination with mutations in genes that cause hereditary breast cancer and ovarian cancer like BRCA1, BRCA2, PALB2 and RAD51C are lethal. Consequently, RAD52 may represent an important target for cancer therapy. In vitro, RAD52 has ssDNA annealing and DNA strand exchange activities. Here, to identify small molecule inhibitors of RAD52 we screened a 372,903-compound library using a fluorescence-quenching assay for ssDNA annealing activity of RAD52. The obtained 70 putative inhibitors were further characterized using biochemical and cell-based assays. As a result, we identified compounds that specifically inhibit the biochemical activities of RAD52, suppress growth of BRCA1- and BRCA2-deficient cells and inhibit RAD52-dependent single-strand annealing (SSA) in human cells. We will use these compounds for development of novel cancer therapy and as a probe to study mechanisms of DNA repair. PMID:26873923

  14. Targeting BRCA1- and BRCA2-deficient cells with RAD52 small molecule inhibitors.

    PubMed

    Huang, Fei; Goyal, Nadish; Sullivan, Katherine; Hanamshet, Kritika; Patel, Mikir; Mazina, Olga M; Wang, Charles X; An, W Frank; Spoonamore, James; Metkar, Shailesh; Emmitte, Kyle A; Cocklin, Simon; Skorski, Tomasz; Mazin, Alexander V

    2016-05-19

    RAD52 is a member of the homologous recombination (HR) pathway that is important for maintenance of genome integrity. While single RAD52 mutations show no significant phenotype in mammals, their combination with mutations in genes that cause hereditary breast cancer and ovarian cancer like BRCA1, BRCA2, PALB2 and RAD51C are lethal. Consequently, RAD52 may represent an important target for cancer therapy. In vitro, RAD52 has ssDNA annealing and DNA strand exchange activities. Here, to identify small molecule inhibitors of RAD52 we screened a 372,903-compound library using a fluorescence-quenching assay for ssDNA annealing activity of RAD52. The obtained 70 putative inhibitors were further characterized using biochemical and cell-based assays. As a result, we identified compounds that specifically inhibit the biochemical activities of RAD52, suppress growth of BRCA1- and BRCA2-deficient cells and inhibit RAD52-dependent single-strand annealing (SSA) in human cells. We will use these compounds for development of novel cancer therapy and as a probe to study mechanisms of DNA repair. PMID:26873923

  15. Women with BRCA1 and BRCA2 mutations survive ovarian cancer at higher rates

    Cancer.gov

    Results from a National Cancer Institute (NCI) sponsored multicenter study published in the Journal of the American Medical Association on January 25, 2012, provides strong evidence that BRCA1 and BRCA2 gene mutation carriers with ovarian cancer were more

  16. Prevalence and Prognostic Role of BRCA1/2 Variants in Unselected Chinese Breast Cancer Patients

    PubMed Central

    Li, Jiayuan; Peng, Zuxiang; Deng, Ling; Zhu, Xuehua; Sun, Yun; Lu, Xuesong; Shen, Fuxiao; Su, Xinying; Zhang, Liying; Gu, Yi; Zheng, Hong

    2016-01-01

    Background The prevalence of BRCA1/2 variants in Chinese breast cancer patients varies among studies. Germline or somatic BRCA1/2 mutations are associated with sensitivity to poly(ADP-ribose) polymerase-1 inhibitors and DNA-damaging agents. We aimed to investigate the distribution of both somatic and germline BRCA1/2 variants in unselected Chinese breast cancer patients, and explore their roles in tumor phenotype and disease prognosis. Methods 507 breast cancer patients, unselected for family history of breast cancer or age at diagnosis, were prospectively enrolled from West China Hospital between Feb. 2008 and Feb. 2014. BRCA1/2 variants in the exons/flanking regions were detected in fresh-frozen tumors using next-generation sequencing and confirmed by independent methods. Germline/somatic status was validated by Sanger sequencing in paired blood/normal tissue. Results BRCA1/2 pathogenic or likely pathogenic (P/LP) variants were detected in 50 patients (9.9%), including 40 germline carriers (18 in BRCA1, 22 in BRCA2), 9 patients with somatic variants (3 in BRCA1, 6 in BRCA2), and 1 patient with concurrent germline/somatic variants in BRCA2. The triple-negative (21.4%) and Luminal B (9.7%) subtypes had higher rates of BRCA1/2 variants. In patients with disease stage 0~II, presence of a germline or somatic BRCA1 P/LP variant increased the risk of relapse as compared to non-carriers [univariate hazard ratio (HR): 3.70, P = 0.04]. Germline BRCA1 P/LP variants, which were associated with aggressive tumor phenotypes, predicted worse disease-free survival in the subgroup of stage 0~II (HR: 4.52, P = 0.02) and N0 (HR: 5.4, P = 0.04) compared to non-carriers. Conclusion A high frequency of germline and somatic BRCA1/2 P/LP variants was detected in unselected Chinese breast cancer patients. Luminal B subtype should be considered as a high-risk population of BRCA1/2 mutation, in addition to triple-negative breast cancer. BRCA1 status was associated with aggressive tumor

  17. Detection of somatic BRCA1/2 mutations in ovarian cancer - next-generation sequencing analysis of 100 cases.

    PubMed

    Koczkowska, Magdalena; Zuk, Monika; Gorczynski, Adam; Ratajska, Magdalena; Lewandowska, Marzena; Biernat, Wojciech; Limon, Janusz; Wasag, Bartosz

    2016-07-01

    The overall prevalence of germline BRCA1/2 mutations is estimated between 11% and 15% of all ovarian cancers. Individuals with germline BRCA1/2 alterations treated with the PARP1 inhibitors (iPARP1) tend to respond better than patients with wild-type BRCA1/2. Additionally, also somatic BRCA1/2 alterations induce the sensitivity to iPARP1. Therefore, the detection of both germline and somatic BRCA1/2 mutations is required for effective iPARP1 treatment. The aim of this study was to identify the frequency and spectrum of germline and somatic BRCA1/2 alterations in a group of Polish patients with ovarian serous carcinoma. In total, 100 formalin-fixed paraffin-embedded (FFPE) ovarian serous carcinoma tissues were enrolled to the study. Mutational analysis of BRCA1/2 genes was performed by using next-generation sequencing. The presence of pathogenic variants was confirmed by Sanger sequencing. In addition, to confirm the germline or somatic status of the mutation, the nonneoplastic tissue was analyzed by bidirectional Sanger sequencing. In total, 27 (28% of patient samples) mutations (20 in BRCA1 and 7 in BRCA2) were identified. For 22 of 27 patients, nonneoplastic cells were available and sequencing revealed the somatic character of two BRCA1 (2/16; 12.5%) and two BRCA2 (2/6; 33%) mutations. Notably, we identified six novel frameshift or nonsense BRCA1/2 mutations. The heterogeneity of the detected mutations confirms the necessity of simultaneous analysis of BRCA1/2 genes in all patients diagnosed with serous ovarian carcinoma. Moreover, the use of tumor tissue for mutational analysis allowed the detection of both somatic and germline BRCA1/2 mutations. PMID:27167707

  18. Co-occurrence of multiple sclerosis and cancer in a BRCA1 positive family.

    PubMed

    Holzmann, Carsten; Bauer, Ingrid; Meyer, Peter

    2013-10-01

    Multiple sclerosis is not known to be a risk factor for subsequent development of cancer. Recently, a multiple sclerosis locus was mapped adjacent to BRCA1 gene. We present a familial case affected by multiple sclerosis and cancer. We identified a c.5266dupC (5382insC) frameshift mutation in a 33-year-old woman with breast cancer, multiple malignant melanomas and multiple sclerosis. The patient's family history shows further cases of multiple sclerosis in BRCA1 mutation carriers. Therefore the presented family may carry a monogenic predisposition for multiple sclerosis nearby to BRCA1. PMID:23954390

  19. Pit-1 inhibits BRCA1 and sensitizes human breast tumors to cisplatin and vitamin D treatment

    PubMed Central

    Seoane, Samuel; Arias, Efigenia; Sigueiro, Rita; Sendon-Lago, Juan; Martinez-Ordoñez, Anxo; Castelao, Esteban; Eiró, Noemí; Garcia-Caballero, Tomás; Macia, Manuel; Lopez-Lopez, Rafael; Maestro, Miguel; Vizoso, Francisco; Mouriño, Antonio; Perez-Fernandez, Roman

    2015-01-01

    The POU class 1 homeobox 1 (POU1F1, also known as Pit-1), pertaining to the Pit-Oct-Unc (POU) family of transcription factors, has been related to tumor growth and metastasis in breast. However, its role in response to breast cancer therapy is unknown. We found that Pit-1 down-regulated DNA-damage and repair genes, and specifically inhibited BRCA1 gene expression, sensitizing breast cancer cells to DNA-damage agents. Administration of 1α, 25-dihydroxy-3-epi-vitamin D3 (3-Epi, an endogenous low calcemic vitamin D metabolite) reduced Pit-1 expression, and synergized with cisplatin, thus, decreasing cell proliferation and apoptosis in vitro, and reducing tumor growth in vivo. In addition, fifteen primary cultures of human breast tumors showed significantly decreased proliferation when treated with 3-Epi+cisplatin, compared to cisplatin alone. This response positively correlated with Pit-1 levels. Our findings demonstrate that high levels of Pit-1 and reduced BRCA1 levels increase breast cancer cell susceptibility to 3-Epi+cisplatin therapy. PMID:25992773

  20. BRCA1 and BRCA2 genetic test in high risk patients and families: counselling and management.

    PubMed

    Marchina, Eleonora; Fontana, Maria Grazia; Speziani, Michela; Salvi, Alessandro; Ricca, Giuseppe; Di Lorenzo, Diego; Gervasi, Maria; Caimi, Luigi; Barlati, Sergio

    2010-12-01

    Hereditary breast cancer accounts for 5-10% of all cases of breast cancer and 10-15% of ovarian cancer and is characterised by dominant inheritance, early onset, the severity of the disease and bilaterality. About 30% of cases with hereditary breast and ovarian cancer have mutations in the BRCA1 and BRCA2 genes. Women with a mutation in the BRCA1 gene have a 80-90% lifetime risk of developing breast cancer, and 40-65% chance of developing ovarian cancer. Most studies carried out throughout the world indicate that the prevalence of BRCA1 and BRCA2 mutation is lower than originally suggested by early studies on large families with several affected members. Studies performed in Italy have reported different prevalence of BRCA1 and BRCA2 mutations, probably due to different selection criteria and to the variability of the techniques used. In this study, we performed a screening of BRCA1 and BRCA2 in families from northern Italy with familial recurrence of breast cancer or ovarian cancer in which the individual risk of patients of being carriers of BRCA1 and BRCA2 mutation was evaluated using BRCAPRO (CAGene) software. We enrolled 27 patients of 101 unrelated families selected when they fulfilled the inclusion criteria of the American Society of Clinical Oncology (ASCO). Specific risk evaluation, genetic test administration if needed, and discussion of the results were offered during multi-disciplinary genetic, surgical and psychological counselling. Seven probands (35%) found BRCA1/2 sequence variation carriers; no BRCA1 and BRCA2 mutations were detected in the remaining 13 probands. Two (15%) patients had BRCA1 mutations and 5 (25%) patients had BRCA2 mutations. In the latter case, BRCA2 delA 9158fs+29stop mutation in exon 22, never previously described and a new sequence variation (T703N) in exon 11 were identified. PMID:21042765

  1. Successful personalized chemotherapy for metastatic gastric cancer based on quantitative BRCA1 mRNA expression level: A case report

    PubMed Central

    HUANG, YING; WU, PUYUAN; LIU, BAORUI; DU, JUAN

    2016-01-01

    Personalized chemotherapy is based on the specific genetic profile of individual patients and is replacing the traditional ‘one size fits all’ medicine. Breast cancer 1 (BRCA1) plays a central role in the chemotherapy-induced DNA damage response. It has been repeatedly demonstrated that BRCA1 mRNA levels were negatively associated with cisplatin sensitivity, but positively associated with docetaxel sensitivity in patients with gastric cancer in experimental and clinical studies. This feature leads to customized chemotherapy based on the BRCA1 mRNA expression level and results in a high efficacy of treatment. The present study describes the case of a 77-year-old patient with metastatic gastric cancer who was treated with personalized chemotherapy based on quantitative BRCA1 mRNA expression level. This study and the available literature data suggest that the expression level of BRCA1 mRNA is dynamic to BRCA1-based chemotherapy. More importantly, de novo assessment of BRCA1 status is a preferable option for ciscisplatin- or docetaxel-resistant patients, since the expression levels of BRCA1 mRNA in certain patients may alter significantly following treatment. Therefore, BRCA1 expression should be assessed for predicting differential chemosensitivity and tailoring chemotherapy in gastric cancer. PMID:27313763

  2. RANKL/RANK control Brca1 mutation-driven mammary tumors.

    PubMed

    Sigl, Verena; Owusu-Boaitey, Kwadwo; Joshi, Purna A; Kavirayani, Anoop; Wirnsberger, Gerald; Novatchkova, Maria; Kozieradzki, Ivona; Schramek, Daniel; Edokobi, Nnamdi; Hersl, Jerome; Sampson, Aishia; Odai-Afotey, Ashley; Lazaro, Conxi; Gonzalez-Suarez, Eva; Pujana, Miguel A; Cimba, For; Heyn, Holger; Vidal, Enrique; Cruickshank, Jennifer; Berman, Hal; Sarao, Renu; Ticevic, Melita; Uribesalgo, Iris; Tortola, Luigi; Rao, Shuan; Tan, Yen; Pfeiler, Georg; Lee, Eva Yhp; Bago-Horvath, Zsuzsanna; Kenner, Lukas; Popper, Helmuth; Singer, Christian; Khokha, Rama; Jones, Laundette P; Penninger, Josef M

    2016-07-01

    Breast cancer is the most common female cancer, affecting approximately one in eight women during their life-time. Besides environmental triggers and hormones, inherited mutations in the breast cancer 1 (BRCA1) or BRCA2 genes markedly increase the risk for the development of breast cancer. Here, using two different mouse models, we show that genetic inactivation of the key osteoclast differentiation factor RANK in the mammary epithelium markedly delayed onset, reduced incidence, and attenuated progression of Brca1;p53 mutation-driven mammary cancer. Long-term pharmacological inhibition of the RANK ligand RANKL in mice abolished the occurrence of Brca1 mutation-driven pre-neoplastic lesions. Mechanistically, genetic inactivation of Rank or RANKL/RANK blockade impaired proliferation and expansion of both murine Brca1;p53 mutant mammary stem cells and mammary progenitors from human BRCA1 mutation carriers. In addition, genome variations within the RANK locus were significantly associated with risk of developing breast cancer in women with BRCA1 mutations. Thus, RANKL/RANK control progenitor cell expansion and tumorigenesis in inherited breast cancer. These results present a viable strategy for the possible prevention of breast cancer in BRCA1 mutant patients. PMID:27241552

  3. Comprehensive spectrum of BRCA1 and BRCA2 deleterious mutations in breast cancer in Asian countries.

    PubMed

    Kwong, Ava; Shin, Vivian Y; Ho, John C W; Kang, Eunyoung; Nakamura, Seigo; Teo, Soo-Hwang; Lee, Ann S G; Sng, Jen-Hwei; Ginsburg, Ophira M; Kurian, Allison W; Weitzel, Jeffrey N; Siu, Man-Ting; Law, Fian B F; Chan, Tsun-Leung; Narod, Steven A; Ford, James M; Ma, Edmond S K; Kim, Sung-Won

    2016-01-01

    Approximately 5%-10% of breast cancers are due to genetic predisposition caused by germline mutations; the most commonly tested genes are BRCA1 and BRCA2 mutations. Some mutations are unique to one family and others are recurrent; the spectrum of BRCA1/BRCA2 mutations varies depending on the geographical origins, populations or ethnic groups. In this review, we compiled data from 11 participating Asian countries (Bangladesh, Mainland China, Hong Kong SAR, Indonesia, Japan, Korea, Malaysia, Philippines, Singapore, Thailand and Vietnam), and from ethnic Asians residing in Canada and the USA. We have additionally conducted a literature review to include other Asian countries mainly in Central and Western Asia. We present the current pathogenic mutation spectrum of BRCA1/BRCA2 genes in patients with breast cancer in various Asian populations. Understanding BRCA1/BRCA2 mutations in Asians will help provide better risk assessment and clinical management of breast cancer. PMID:26187060

  4. Analysis of novel mutations in BRCA1 in Iranian families with breast cancer.

    PubMed

    Sadr-Nabavi, Ariane; Dastpak, Mahtab; Homaei-Shandiz, Fatemeh; Bahrami, Ahmad Reza; Bidkhori, Hamid-Reza; Raeesolmohaddeseen, Mahmood

    2014-06-01

    In Iran and the rest of the world, breast cancer (BC) is the most common malignancy in women. Familial history and age are significant risk factors for the development of this disease in Iran. Most hereditary BCs are associated with inherited mutations in the BRCA1 and BRCA2 genes. Some recent studies demonstrated that BRCA1 mutations are seen in high-risk women with family histories of BC. In this report we investigated all BRCA1 exons from 40 female patients with family histories of BC and one BC twin, and report a novel mutation in this gene in one patient. As controls, BRCA1 exons from 100 normal women and the BC-free twin of the BC twin were also examined for this mutation. None of the women in the normal group harbored the mutation. Whether this variation is specific for the Iranian population or for special subgroups remains to be determined. PMID:25041116

  5. Pathogenicity evaluation of BRCA1 and BRCA2 unclassified variants identified in Portuguese breast/ovarian cancer families.

    PubMed

    Santos, Catarina; Peixoto, Ana; Rocha, Patrícia; Pinto, Pedro; Bizarro, Susana; Pinheiro, Manuela; Pinto, Carla; Henrique, Rui; Teixeira, Manuel R

    2014-05-01

    Hereditary breast/ovarian cancer syndrome is caused by germline deleterious mutations in BRCA1 and BRCA2. A major problem of genetic testing and counseling is the finding of variants of uncertain significance (VUS). We sought to ascertain the pathogenicity of 25 BRCA1 and BRCA2 VUS identified in Portuguese families during genetic testing. We performed cosegregation analysis of VUS with cancer in families, evaluated their frequency in unaffected controls, and looked for loss of heterozygosity in tumors. In addition, three different bioinformatic algorithms were used (Interactive Biosoftware, ESEfinder, and PolyPhen). Finally, six VUS located in exon-intron boundaries were analyzed by RT-PCR. We found that seven variants segregated with the disease, six variants co-occurred with a pathogenic mutation in the same gene, and four variants co-occurred with a deleterious mutation in the other BRCA gene. By RT-PCR, we observed that four variants (BRCA1 c.4484G>T, BRCA2 c.682-2A>C, BRCA2 c.8488-1G>A, and BRCA2 c.8954-5A>G) disrupted splicing. After the combined analysis, we were able to classify 4 splicing variants as pathogenic mutations, 16 variants as neutral, and 3 variants as polymorphisms; only 2 variants remained classified as VUS. This work highlights the contribution of DNA, RNA, and in silico data to assess the pathogenicity of BRCA1/2 VUS, which, in turn, allows more accurate genetic counseling and clinical management of the families carrying them. PMID:24607278

  6. Loss of heterozygosity at the BRCA1 locus in Tunisian women with sporadic breast cancer.

    PubMed

    Charef-Hamza, Sameh; Trimeche, Mounir; Ziadi, Sonia; Amara, Khaled; Gaddas, Naim; Mokni, Moncef; Sriha, Badreddine; Yacoubi, Tahar; Korbi, Sadok

    2005-06-28

    Breast cancer in Tunisia is characterized by a much higher incidence of aggressiveness compared with Western countries. The pattern of allelic loss at the BRCA1 locus in Tunisian women with breast carcinoma has not been studied. Therefore, the aim of this present preliminary study was mainly focused on loss of heterozygosity (LOH) analysis of the BRCA1 gene to determine if this tumor suppressor gene is involved in sporadic breast carcinoma among Tunisian women. We investigate allelic losses by analyzing three microsatellite markers in the BRCA1 region, in a panel of 21 human breast tumors. D17S1322 marker had the highest frequency of LOH (59%), followed by the D17S1323 (35%), and EDH-17B (20%). Collectively out of 21 informative cases 13 (62%) showed LOH at at least one BRCA1 locus. This data provides evidence that allelic loss at BRCA1 is a frequent event in sporadic breast tumorigenesis among Tunisian women, and suggests that the BRCA1 gene might play an important role as a tumor suppressor gene. PMID:15914269

  7. Germline mutations in BRCA1, BRCA2, CHEK2 and TP53 in patients at high-risk for HBOC: characterizing a Northeast Brazilian Population

    PubMed Central

    Felix, Gabriela ES; Abe-Sandes, Camila; Machado-Lopes, Taísa MB; Bomfim, Thaís F; Guindalini, Rodrigo Santa Cruz; Santos, Vanessa Catarine SAR; Meyer, Lorena; Oliveira, Polyanna C; Cláudio Neiva, João; Meyer, Roberto; Romeo, Maura; Betânia Toralles, Maria; Nascimento, Ivana; Abe-Sandes, Kiyoko

    2014-01-01

    Considering the importance of BRCA1, BRCA2, CHEK2 and TP53 in the development of hereditary early-onset breast and ovarian cancer and that the genetic susceptibility profile of the Northeast population from Brazil has never been analyzed, this study aimed to verify the frequency of mutations of clinical significance in these genes in high-risk hereditary breast and ovarian cancer (HBOC) syndrome patients from that region. DNA samples from 106 high-risk unrelated patients mostly from Bahia, the biggest state in the Northeast region, were analyzed. These patients underwent full BRCA1 gene sequencing, screening for common founder mutations in the BRCA2, CHEK2 and TP53 genes and genetic ancestry analysis with nine ancestry informative markers. The positive results were confirmed by two sequencing reactions. Three mutations of clinical significance were found: BRCA1 p.R71G (4.71%), 3450del4 (3.77%) and TP53 p.R337H (0.94%). The genetic ancestry analysis showed a high European ancestry contribution (62.2%) as well as considerable African (31.2%) and Amerindian (6.6%) ancestry contributions (r2=0.991); this degree of heterogeneity was also significant in the population structure analysis (r=0.604). This population is highly admixed with a different spectrum of genetic susceptibility, with the Galician founder mutation BRCA1 p.R71G accounting for 50% of all identified mutations in high-risk HBOC patients. TP53 p.R337H was also significantly frequent; thus, the combined screening of BRCA1/2 and TP53 should be offered to high-risk HBOC patients from Northeast Brazil. PMID:27081505

  8. Tumor suppressor BRCA1 epigenetically controls oncogenic microRNA-155

    PubMed Central

    Chang, Suhwan; Wang, Rui-Hong; Akagi, Keiko; Kim, Kyung-Ae; Martin, Betty K; Cavallone, Luca; Haines, Diana C; Basik, Mark; Mai, Phuong; Poggi, Elizabeth; Isaacs, Claudine; Looi, Lai M; Mun, Kein S; Greene, Mark H; Byers, Stephen W; Teo, Soo H; Deng, Chu-Xia; Sharan, Shyam K

    2012-01-01

    BRCA1, a well-known tumor suppressor with multiple interacting partners, is predicted to have diverse biological functions. However, so far its only well-established role is in the repair of damaged DNA and cell cycle regulation. In this regard, the etiopathological study of low-penetrant variants of BRCA1 provides an opportunity to uncover its other physiologically important functions. Using this rationale, we studied the R1699Q variant of BRCA1, a potentially moderate-risk variant, and found that it does not impair DNA damage repair but abrogates the repression of microRNA-155 (miR-155), a bona fide oncomir. Mechanistically, we found that BRCA1 epigenetically represses miR-155 expression via its association with HDAC2, which deacetylates histones H2A and H3 on the miR-155 promoter. We show that overexpression of miR-155 accelerates whereas the knockdown of miR-155 attenuates the growth of tumor cell lines in vivo. Our findings demonstrate a new mode of tumor suppression by BRCA1 and suggest that miR-155 is a potential therapeutic target for BRCA1-deficient tumors. PMID:21946536

  9. BRCC36 is essential for ionizing radiation-induced BRCA1 phosphorylation and nuclear foci formation.

    PubMed

    Chen, Xiaowei; Arciero, Cletus A; Wang, Chunrong; Broccoli, Dominique; Godwin, Andrew K

    2006-05-15

    We have previously reported the identification and characterization of a novel BRCA1/2 interacting protein complex, BRCC (BRCA1/2-containing complex). BRCC36, one of the proteins in BRCC, directly interacts with BRCA1, and regulates the ubiquitin E3 ligase activity of BRCC. Importantly, BRCC36 is aberrantly expressed in the vast majority of breast tumors, indicating a potential role in the pathogenesis of this disease. To further elucidate the functional consequence of abnormal BRCC36 expression in breast cancer, we have done in vivo silencing studies using small interfering RNAs targeting BRCC36 in breast cancer cell lines, i.e., MCF-7, ZR-75-1, and T47D. Knock-down of BRCC36 alone does not affect cell growth, but when combined with ionizing radiation (IR) exposure, it leads to an increase in the percentage of cells undergoing apoptosis when compared with the small interfering RNA control group in breast cancer cells. Immunoblot analysis shows that inhibition of BRCC36 has no effect on the activation of ATM, expression of p21 and p53, or BRCA1-BARD1 interaction following IR exposure. Importantly, BRCC36 depletion disrupts IR-induced phosphorylation of BRCA1. Immunofluorescent staining of BRCA1 and gamma-H2AX indicates that BRCC36 depletion prevents the formation of BRCA1 nuclear foci in response to DNA damage in breast cancer cells. These results show that down-regulation of BRCC36 expression impairs the DNA repair pathway activated in response to IR by inhibiting BRCA1 activation, thereby sensitizing breast cancer cells to IR-induced apoptosis. PMID:16707425

  10. A germline mutation in the BRCA1 3’UTR predicts Stage IV breast cancer

    PubMed Central

    2014-01-01

    Background A germline, variant in the BRCA1 3’UTR (rs8176318) was previously shown to predict breast and ovarian cancer risk in women from high-risk families, as well as increased risk of triple negative breast cancer. Here, we tested the hypothesis that this variant predicts tumor biology, like other 3’UTR mutations in cancer. Methods The impact of the BRCA1-3’UTR-variant on BRCA1 gene expression, and altered response to external stimuli was tested in vitro using a luciferase reporter assay. Gene expression was further tested in vivo by immunoflourescence staining on breast tumor tissue, comparing triple negative patient samples with the variant (TG or TT) or non-variant (GG) BRCA1 3’UTR. To determine the significance of the variant on clinically relevant endpoints, a comprehensive collection of West-Irish breast cancer patients were tested for the variant. Finally, an association of the variant with breast screening clinical phenotypes was evaluated using a cohort of women from the High Risk Breast Program at the University of Vermont. Results Luciferase reporters with the BRCA1-3’UTR-variant (T allele) displayed significantly lower gene expression, as well as altered response to external hormonal stimuli, compared to the non-variant 3’UTR (G allele) in breast cancer cell lines. This was confirmed clinically by the finding of reduced BRCA1 gene expression in triple negative samples from patients carrying the homozygous TT variant, compared to non-variant patients. The BRCA1-3’UTR-variant (TG or TT) also associated with a modest increased risk for developing breast cancer in the West-Irish cohort (OR = 1.4, 95% CI 1.1-1.8, p = 0.033). More importantly, patients with the BRCA1-3’UTR-variant had a 4-fold increased risk of presenting with Stage IV disease (p = 0.018, OR = 3.37, 95% CI 1.3-11.0). Supporting that this finding is due to tumor biology, and not difficulty screening, obese women with the BRCA1-3’UTR-variant had

  11. Radiosensitivity to high energy iron ions is influenced by heterozygosity for Atm, Rad9 and Brca1

    NASA Astrophysics Data System (ADS)

    Zhou, G.; Smilenov, L. B.; Lieberman, H. B.; Ludwig, T.; Hall, E. J.

    2010-09-01

    Loss of function of DNA repair genes has been implicated in the development of many types of cancer. In the last several years, heterozygosity leading to haploinsufficiency for proteins involved in DNA repair was shown to play a role in genomic instability and carcinogenesis after DNA damage is induced, for example by ionizing radiation. Since the effect of heterozygosity for one gene is relatively small, we hypothesize that predisposition to cancer could be a result of the additive effect of heterozygosity for two or more genes critical to pathways that control DNA damage signaling, repair or apoptosis. We investigated the role of heterozygosity for Atm, Rad9 and Brca1 on cell oncogenic transformation and cell survival induced by 1 GeV/ n56Fe ions. Our results show that cells heterozygous for both Atm and Rad9 or Atm and Brca1 have high survival rates and are more sensitive to transformation by high energy iron ions when compared with wild-type controls or cells haploinsufficient for only one of these proteins. Since mutations or polymorphisms for similar genes exist in a small percentage of the human population, we have identified a radiosensitive sub-population. This finding has several implications. First, the existence of a radiosensitive sub-population may distort the shape of the dose-response relationship. Second, it would not be ethical to put exceptionally radiosensitive individuals into a setting where they may potentially be exposed to substantial doses of radiation.

  12. RADIOSENSITIVITY TO HIGH ENERGY IRON IONS IS INFLUENCED BY HETEROZYGOSITY for ATM, RAD9 and BRCA1.

    PubMed

    Zhou, G; Smilenov, L B; Lieberman, H B; Ludwig, T; Hall, E J

    2010-09-01

    Loss of function of DNA repair genes has been implicated in the development of many types of cancer. In the last several years, heterozygosity leading to haploinsufficiency for proteins involved in DNA repair was shown to play a role in genomic instability and carcinogenesis after DNA damage is induced, for example by ionizing radiation. Since the effect of heterozygosity for one gene is relatively small, we hypothesize that predisposition to cancer could be a result of the additive effect of heterozygosity for two or more genes critical to pathways that control DNA damage signaling, repair or apoptosis. We investigated the role of heterozygosity for Atm, Rad9 and Brca1 on cell oncogenic transformation and cell survival induced by 1GeV/n (56)Fe ions. Our results show that cells heterozygous for both Atm and Rad9 or Atm and Brca1 have high survival rates and are more sensitive to transformation by high energy Iron ions when compared with wild-type controls or cells haploinsufficient for only one of these proteins. Since mutations or polymorphisms for similar genes exist in a small percentage of the human population, we have identified a radiosensitive sub-population. This finding has several implications. First, the existence of a radiosensitive sub-population may distort the shape of the dose-response relationship. Second, it would not be ethical to put exceptionally radiosensitive individuals into a setting where they may potentially be exposed to substantial doses of radiation. PMID:24431481

  13. RADIOSENSITIVITY TO HIGH ENERGY IRON IONS IS INFLUENCED BY HETEROZYGOSITY for ATM, RAD9 and BRCA1

    PubMed Central

    Zhou, G.; Smilenov, L. B.; Lieberman, H. B.; Ludwig, T.; Hall, E. J.

    2013-01-01

    Loss of function of DNA repair genes has been implicated in the development of many types of cancer. In the last several years, heterozygosity leading to haploinsufficiency for proteins involved in DNA repair was shown to play a role in genomic instability and carcinogenesis after DNA damage is induced, for example by ionizing radiation. Since the effect of heterozygosity for one gene is relatively small, we hypothesize that predisposition to cancer could be a result of the additive effect of heterozygosity for two or more genes critical to pathways that control DNA damage signaling, repair or apoptosis. We investigated the role of heterozygosity for Atm, Rad9 and Brca1 on cell oncogenic transformation and cell survival induced by 1GeV/n 56Fe ions. Our results show that cells heterozygous for both Atm and Rad9 or Atm and Brca1 have high survival rates and are more sensitive to transformation by high energy Iron ions when compared with wild-type controls or cells haploinsufficient for only one of these proteins. Since mutations or polymorphisms for similar genes exist in a small percentage of the human population, we have identified a radiosensitive sub-population. This finding has several implications. First, the existence of a radiosensitive sub-population may distort the shape of the dose-response relationship. Second, it would not be ethical to put exceptionally radiosensitive individuals into a setting where they may potentially be exposed to substantial doses of radiation. PMID:24431481

  14. Analysis of SLX4/FANCP in non-BRCA1/2-mutated breast cancer families

    PubMed Central

    2012-01-01

    Background Genes that, when mutated, cause Fanconi anemia or greatly increase breast cancer risk encode for proteins that converge on a homology-directed DNA damage repair process. Mutations in the SLX4 gene, which encodes for a scaffold protein involved in the repair of interstrand cross-links, have recently been identified in unclassified Fanconi anemia patients. A mutation analysis of SLX4 in German or Byelorussian familial cases of breast cancer without detected mutations in BRCA1 or BRCA2 has been completed, with globally negative results. Methods The genomic region of SLX4, comprising all exons and exon-intron boundaries, was sequenced in 94 Spanish familial breast cancer cases that match a criterion indicating the potential presence of a highly-penetrant germline mutation, following exclusion of BRCA1 or BRCA2 mutations. Results This mutational analysis revealed extensive genetic variation of SLX4, with 21 novel single nucleotide variants; however, none could be linked to a clear alteration of the protein function. Nonetheless, genotyping 10 variants (nine novel, all missense amino acid changes) in a set of controls (138 women and 146 men) did not detect seven of them. Conclusions Overall, while the results of this study do not identify clearly pathogenic mutations of SLX4 contributing to breast cancer risk, further genetic analysis, combined with functional assays of the identified rare variants, may be warranted to conclusively assess the potential link with the disease. PMID:22401137

  15. The carboxyl-terminal of BRCA1 is required for subnuclear assembly of RAD51 after treatment with cisplatin but not ionizing radiation in human breast and ovarian cancer cells

    SciTech Connect

    Zhou Chenyi; Huang Peng; Liu Jinsong . E-mail: jliu@mdanderson.org

    2005-10-28

    BRCA1 plays an important role in maintaining genomic stability through its involvement in DNA repair. Although it is known that BRCA1 and RAD51 form distinct DNA repair subnuclear complexes, or foci, following environmental insults to the DNA, the role of BRCA1 in this process remains to be characterized. The purpose of the study was therefore to determine the role of BRCA1 in the formation of RAD51 foci following treatment with cisplatin and ionizing radiation. We found that although a functional BRCA1 is required for the subnuclear assembly of BRCA1 foci following treatment with either ionizing radiation or cisplatin, a functional BRCA1 is required for RAD51 foci to form following treatment with cisplatin but not with ionizing radiation. Similar results were obtained in SKOV-3 cells when the level of BRCA1 expression was knocked down by stable expression of a retrovirus-mediated small-interfering RNA against BRCA1. We also found that the carboxyl-terminal of BRCA1 contains uncharacterized phosphorylation sites that are responsive to cisplatin. The functional BRCA1 is also required for breast and ovarian cancer cells to mount resistance to cisplatin. These results suggest that the carboxyl-terminal of BRCA1 is required for the cisplatin-induced recruitment of RAD51 to the DNA-damage site, which may contribute to cisplatin resistance.

  16. HUWE1 interacts with BRCA1 and promotes its degradation in the ubiquitin–proteasome pathway (Biochemical and Biophysical Research Communications, v. 444, isse 4)

    SciTech Connect

    Wang, Xiaozhen; Lu, Guang; Li, Li; Yi, Juan; Yan, Kaowen; Wang, Yaqing; Zhu, Baili; Kuang, Jingyu; Lin, Ming; Zhang, Sha; Shao, Genze

    2014-02-21

    Highlights: • The 2000–2634aa region of HUWE1 mediates the interaction with BRCA1 degron. • HUWE1 promotes the degradation of BRCA1 through the ubiquitin–proteasome pathway. • HUWE1 expression is inversely correlated with BRCA1 in breast cancer cells. • RNAi inhibition of HUWE1 confers increased resistance of MCF-10F cells to IR and MMC. - Abstract: The cellular BRCA1 protein level is essential for its tumor suppression activity and is tightly regulated through multiple mechanisms including ubiquitn–proteasome system. E3 ligases are involved to promote BRCA1 for ubiquitination and degradation. Here, we identified HUWE1/Mule/ARF-BP1 as a novel BRCA1-interacting protein involved in the control of BRCA1 protein level. HUWE1 binds BRCA1 through its N-terminus degron domain. Depletion of HUWE1 by siRNA-mediated interference significantly increases BRCA1 protein levels and prolongs the half-life of BRCA1. Moreover, exogenous expression of HUWE1 promotes BRCA1 degradation through the ubiquitin–proteasome pathway, which could explain an inverse correlation between HUWE1 and BRCA1 levels in MCF10F, MCF7 and MDA-MB-231 breast cancer cells. Consistent with a functional role for HUWE1 in regulating BRCA1-mediated cellular response to DNA damage, depletion of HUWE1 by siRNA confers increased resistance to ionizing radiation and mitomycin. These data indicate that HUWE1 is a critical negative regulator of BRCA1 and suggest a new molecular mechanism for breast cancer pathogenesis.

  17. HUWE1 interacts with BRCA1 and promotes its degradation in the ubiquitin–proteasome pathway (Biochemical and Biophysical Research Communications, v. 444 issue 3)

    SciTech Connect

    Wang, Xiaozhen; Lu, Guang; Li, Li; Yi, Juan; Yan, Kaowen; Wang, Yaqing; Zhu, Baili; Kuang, Jingyu; Lin, Ming; Zhang, Sha; Shao, Genze

    2014-02-14

    Highlights: • The 2000–2634 aa region of HUWE1 mediates the interaction with BRCA1 degron. • HUWE1 promotes the degradation of BRCA1 through the ubiquitin–proteasome pathway. • HUWE1 expression is inversely correlated with BRCA1 in breast cancer cells. • RNAi inhibition of HUWE1 confers increased resistance of MCF-10F cells to IR and MMC. - Abstract: The cellular BRCA1 protein level is essential for its tumor suppression activity and is tightly regulated through multiple mechanisms including ubiquitn–proteasome system. E3 ligases are involved to promote BRCA1 for ubiquitination and degradation. Here, we identified HUWE1/Mule/ARF-BP1 as a novel BRCA1-interacting protein involved in the control of BRCA1 protein level. HUWE1binds BRCA1 through its N-terminus degron domain. Depletion of HUWE1 by siRNA-mediated interference significantly increases BRCA1 protein levels and prolongs the half-life of BRCA1. Moreover, exogenous expression of HUWE1 promotes BRCA1 degradation through the ubiquitin–proteasome pathway, which could explain an inverse correlation between HUWE1 and BRCA1 levels in MCF10F, MCF7 and MDA-MB-231 breast cancer cells. Consistent with a functional role for HUWE1 in regulating BRCA1-mediated cellular response to DNA damage, depletion of HUWE1 by siRNA confers increased resistance to ionizing radiation and mitomycin. These data indicate that HUWE1 is a critical negative regulator of BRCA1 and suggest a new molecular mechanism for breast cancer pathogenesis.

  18. Prevalence of BRCA1 and BRCA2 germline mutations in patients with triple-negative breast cancer.

    PubMed

    Wong-Brown, Michelle W; Meldrum, Cliff J; Carpenter, Jane E; Clarke, Christine L; Narod, Steven A; Jakubowska, Anna; Rudnicka, Helena; Lubinski, Jan; Scott, Rodney J

    2015-02-01

    Triple-negative breast cancers (TNBC) lack expression of oestrogen, progesterone and HER2 receptors. The gene expression profiles of TNBCs are similar to those of breast tumours in women with BRCA1 mutations. Reports to date indicate that up to 20 % of TNBC patients harbour germline BRCA mutations; however, the prevalence of BRCA mutations in TNBC patients varies widely between countries and from study to study. We studied 774 women with triple-negative breast cancer, diagnosed on average at age 58.0 years. Samples of genomic DNA were provided by the Australian Breast Cancer Tissue Bank (ABCTB) (439 patients) and by the Department of Genetics and Pathology of the Pomeranian Medical University (335 patients). The entire coding regions and the exon-intron boundaries of BRCA1 and BRCA2 were amplified and sequenced by next-generation sequencing. We identified a BRCA1 or BRCA2 mutation in 74 of 774 (9.6 %) triple-negative patients. The mutation prevalence was 9.3 % in Australia and was 9.9 % in Poland. In both countries, the mean age of diagnoses of BRCA1 mutation carriers was significantly lower than that of non-carriers, while the age of onset of BRCA2 mutation carriers was similar to that of non-carriers. In the Australian cohort, 59 % of the mutation-positive patients did not have a family history of breast or ovarian cancer, and would not have qualified for genetic testing. The triple-negative phenotype should be added as a criterion to genetic screening guidelines. PMID:25682074

  19. Design and validation of a next generation sequencing assay for hereditary BRCA1 and BRCA2 mutation testing

    PubMed Central

    Maguire, Jared R.; Chu, Clement S.; Haque, Imran S.; Lai, Henry; Mar-Heyming, Rebecca; Ready, Kaylene; Vysotskaia, Valentina S.; Evans, Eric A.

    2016-01-01

    Hereditary breast and ovarian cancer syndrome, caused by a germline pathogenic variant in the BRCA1 or BRCA2 (BRCA1/2) genes, is characterized by an increased risk for breast, ovarian, pancreatic and other cancers. Identification of those who have a BRCA1/2 mutation is important so that they can take advantage of genetic counseling, screening, and potentially life-saving prevention strategies. We describe the design and analytic validation of the Counsyl Inherited Cancer Screen, a next-generation-sequencing-based test to detect pathogenic variation in the BRCA1 and BRCA2 genes. We demonstrate that the test is capable of detecting single-nucleotide variants (SNVs), short insertions and deletions (indels), and copy-number variants (CNVs, also known as large rearrangements) with zero errors over a 114-sample validation set consisting of samples from cell lines and deidentified patient samples, including 36 samples with BRCA1/2pathogenic germline mutations. PMID:27375968

  20. A novel crosstalk between BRCA1 and poly (ADP-ribose) polymerase 1 in breast cancer

    PubMed Central

    Li, Da; Bi, Fang-Fang; Chen, Na-Na; Cao, Ji-Min; Sun, Wu-Ping; Zhou, Yi-Ming; Li, Chun-Yan; Yang, Qing

    2014-01-01

    BRCA mutations are the main known hereditary factor for breast cancer. Notably, poly (ADP-ribose) polymerase 1 (PARP1) expression status plays a critical role in breast cancer progression and the clinical development of PARP1 inhibitors to treat BRCA-mutated breast cancer has advanced rapidly. However, dynamic crosstalk between BRCA1 and PARP1 remains largely unknown. Here, we showed that: (i) BRCA1 inactivation events (mutation, promoter methylation, or knockdown) were accompanied by increased PARP1 and nicotinamide adenine dinucleotide (NAD) levels, and a subsequent increase in NAD-dependent PARP1 activity in MDA-MB-231 and primary breast cancer cells; (ii) the overexpression of BRCA1 resulted in decreased PARP1 and NAD levels, and a subsequent impairment in NAD-dependent PARP1 activity in MDA-MB-231 and primary breast cancer cells; and (iii) intracellular NAD levels were largely responsible for regulating PARP1 activity in breast cancer cells, and NAD levels were positively correlated with PARP1 activity in human breast cancer specimens (R = 0.647, P < 0.001). Interestingly, the high efficiency of PARP1 triggered by BRCA1 inactivation may further inhibit BRCA1 transcription by NAD depletion. These results highlight a novel interaction between BRCA1 and PARP1, which may be beneficial for the dynamic balance between BRCA1 and PARP1-related biologic processes, especially for maintaining stable DNA repair ability. All of this may improve our understanding of the basic molecular mechanism underlying BRCA1- and PARP1-related breast cancer progression. PMID:25485588

  1. BRCA1 deficiency in ovarian cancer is associated with alteration in expression of several key regulators of cell motility – A proteomics study

    PubMed Central

    Gau, David M; Lesnock, Jamie L; Hood, Brian L; Bhargava, Rohit; Sun, Mai; Darcy, Kathleen; Luthra, Soumya; Chandran, Uma; Conrads, Thomas P; Edwards, Robert P; Kelley, Joseph L; Krivak, Thomas C; Roy, Partha

    2015-01-01

    Functional loss of expression of breast cancer susceptibility gene 1(BRCA1) has been implicated in genomic instability and cancer progression. There is emerging evidence that BRCA1 gene product (BRCA1) also plays a role in cancer cell migration. We performed a quantitative proteomics study of EOC patient tumor tissues and identified changes in expression of several key regulators of actin cytoskeleton/cell adhesion and cell migration (CAPN1, 14-3-3, CAPG, PFN1, SPTBN1, CFN1) associated with loss of BRCA1 function. Gene expression analyses demonstrate that several of these proteomic hits are differentially expressed between early and advanced stage EOC thus suggesting clinical relevance of these proteins to disease progression. By immunohistochemistry of ovarian tumors with BRCA1+/+ and BRCA1null status, we further verified our proteomic-based finding of elevated PFN1 expression associated with BRCA1 deficiency. Finally, we established a causal link between PFN1 and BRCA1-induced changes in cell migration thus uncovering a novel mechanistic basis for BRCA1-dependent regulation of ovarian cancer cell migration. Overall, findings of this study open up multiple avenues by which BRCA1 can potentially regulate migration and metastatic phenotype of EOC cells. PMID:25927284

  2. CHK2–BRCA1 tumor-suppressor axis restrains oncogenic Aurora-A kinase to ensure proper mitotic microtubule assembly

    PubMed Central

    Ertych, Norman; Stolz, Ailine; Valerius, Oliver; Braus, Gerhard H.; Bastians, Holger

    2016-01-01

    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. PMID:26831064

  3. Characterization of Promiscuous Binding of Phosphor Ligands to Breast-Cancer-Gene 1 (BRCA1) C-Terminal (BRCT): Molecular Dynamics, Free Energy, Entropy and Inhibitor Design.

    PubMed

    You, Wanli; Huang, Yu-Ming M; Kizhake, Smitha; Natarajan, Amarnath; Chang, Chia-En A

    2016-08-01

    Inhibition of the protein-protein interaction (PPI) mediated by breast-cancer-gene 1 C-terminal (BRCT) is an attractive strategy to sensitize breast and ovarian cancers to chemotherapeutic agents that induce DNA damage. Such inhibitors could also be used for studies to understand the role of this PPI in DNA damage response. However, design of BRCT inhibitors is challenging because of the inherent flexibility associated with this domain. Several studies identified short phosphopeptides as tight BRCT binders. Here we investigated the thermodynamic properties of 18 phosphopeptides or peptide with phosphate mimic and three compounds with phosphate groups binding to BRCT to understand promiscuous molecular recognition and guide inhibitor design. We performed molecular dynamics (MD) simulations to investigate the interactions between inhibitors and BRCT and their dynamic behavior in the free and bound states. MD simulations revealed the key role of loops in altering the shape and size of the binding site to fit various ligands. The mining minima (M2) method was used for calculating binding free energy to explore the driving forces and the fine balance between configuration entropy loss and enthalpy gain. We designed a rigidified ligand, which showed unfavorable experimental binding affinity due to weakened enthalpy. This was because it lacked the ability to rearrange itself upon binding. Investigation of another phosphate group containing compound, C1, suggested that the entropy loss can be reduced by preventing significant narrowing of the energy well and introducing multiple new compound conformations in the bound states. From our computations, we designed an analog of C1 that introduced new intermolecular interactions to strengthen attractions while maintaining small entropic penalty. This study shows that flexible compounds do not always encounter larger entropy penalty, compared with other more rigid binders, and highlights a new strategy for inhibitor design. PMID

  4. Characterization of Promiscuous Binding of Phosphor Ligands to Breast-Cancer-Gene 1 (BRCA1) C-Terminal (BRCT): Molecular Dynamics, Free Energy, Entropy and Inhibitor Design

    PubMed Central

    Huang, Yu-ming M.; Kizhake, Smitha; Natarajan, Amarnath; Chang, Chia-en A.

    2016-01-01

    Inhibition of the protein-protein interaction (PPI) mediated by breast-cancer-gene 1 C-terminal (BRCT) is an attractive strategy to sensitize breast and ovarian cancers to chemotherapeutic agents that induce DNA damage. Such inhibitors could also be used for studies to understand the role of this PPI in DNA damage response. However, design of BRCT inhibitors is challenging because of the inherent flexibility associated with this domain. Several studies identified short phosphopeptides as tight BRCT binders. Here we investigated the thermodynamic properties of 18 phosphopeptides or peptide with phosphate mimic and three compounds with phosphate groups binding to BRCT to understand promiscuous molecular recognition and guide inhibitor design. We performed molecular dynamics (MD) simulations to investigate the interactions between inhibitors and BRCT and their dynamic behavior in the free and bound states. MD simulations revealed the key role of loops in altering the shape and size of the binding site to fit various ligands. The mining minima (M2) method was used for calculating binding free energy to explore the driving forces and the fine balance between configuration entropy loss and enthalpy gain. We designed a rigidified ligand, which showed unfavorable experimental binding affinity due to weakened enthalpy. This was because it lacked the ability to rearrange itself upon binding. Investigation of another phosphate group containing compound, C1, suggested that the entropy loss can be reduced by preventing significant narrowing of the energy well and introducing multiple new compound conformations in the bound states. From our computations, we designed an analog of C1 that introduced new intermolecular interactions to strengthen attractions while maintaining small entropic penalty. This study shows that flexible compounds do not always encounter larger entropy penalty, compared with other more rigid binders, and highlights a new strategy for inhibitor design. PMID

  5. BRCA1-IRIS regulates cyclin D1 expression in breast cancer cells

    SciTech Connect

    Nakuci, Enkeleda; Mahner, Sven; DiRenzo, James; ElShamy, Wael M. . E-mail: wael_elshamy@dfci.harvard.edu

    2006-10-01

    The regulator of cell cycle progression, cyclin D1, is up-regulated in breast cancer cells; its expression is, in part, dependent on ER{alpha} signaling. However, many ER{alpha}-negative tumors and tumor cell lines (e.g., SKBR3) also show over-expression of cyclin D1. This suggests that, in addition to ER{alpha} signaling, cyclin D1 expression is under the control of other signaling pathways; these pathways may even be over-expressed in the ER{alpha}-negative cells. We previously noticed that both ER{alpha}-positive and -negative cell lines over-express BRCA1-IRIS mRNA and protein. Furthermore, the level of over-expression of BRCA1-IRIS in ER{alpha}-negative cell lines even exceeded its over-expression level in ER{alpha}-positive cell lines. In this study, we show that: (1) BRCA1-IRIS forms complex with two of the nuclear receptor co-activators, namely, SRC1 and SRC3 (AIB1) in an ER{alpha}-independent manner. (2) BRCA1-IRIS alone, or in connection with co-activators, is recruited to the cyclin D1 promoter through its binding to c-Jun/AP1 complex; this binding activates the cyclin D1 expression. (3) Over-expression of BRCA1-IRIS in breast cells over-activates JNK/c-Jun; this leads to the induction of cyclin D1 expression and cellular proliferation. (4) BRCA1-IRIS activation of JNK/c-Jun/AP1 appears to account for this, because in cells that were depleted from BRCA1-IRIS, JNK remained inactive. However, depletion of SRC1 or SRC3 instead reduced c-Jun expression. Our data suggest that this novel signaling pathway links BRCA1-IRIS to cellular proliferation through c-Jun/AP1 nuclear pathway; finally, this culminates in the increased expression of the cyclin D1 gene.

  6. miR-342 Regulates BRCA1 Expression through Modulation of ID4 in Breast Cancer

    PubMed Central

    Crippa, Elisabetta; Lusa, Lara; De Cecco, Loris; Marchesi, Edoardo; Calin, George Adrian; Radice, Paolo; Manoukian, Siranoush; Peissel, Bernard; Daidone, Maria Grazia

    2014-01-01

    A miRNAs profiling on a group of familial and sporadic breast cancers showed that miRNA-342 was significantly associated with estrogen receptor (ER) levels. To investigate at functional level the role of miR-342 in the pathogenesis of breast cancer, we focused our attention on its “in silico” predicted putative target gene ID4, a transcription factor of the helix-loop-helix protein family whose expression is inversely correlated with that of ER. ID4 is expressed in breast cancer and can negatively regulate BRCA1 expression. Our results showed an inverse correlation between ID4 and miR-342 as well as between ID4 and BRCA1 expression. We functionally validated the interaction between ID4 and miR-342 in a reporter Luciferase system. Based on these findings, we hypothesized that regulation of ID4 mediated by miR-342 could be involved in the pathogenesis of breast cancer by downregulating BRCA1 expression. We functionally demonstrated the interactions between miR-342, ID4 and BRCA1 in a model provided by ER-negative MDA-MB-231 breast cancer cell line that presented high levels of ID4. Overexpression of miR-342 in these cells reduced ID4 and increased BRCA1 expression, supporting a possible role of this mechanism in breast cancer. In the ER-positive MCF7 and in the BRCA1-mutant HCC1937 cell lines miR-342 over-expression only reduced ID4. In the cohort of patients we studied, a correlation between miR-342 and BRCA1 expression was found in the ER-negative cases. As ER-negative cases were mainly BRCA1-mutant, we speculate that the mechanism we demonstrated could be involved in the decreased expression of BRCA1 frequently observed in non BRCA1-mutant breast cancers and could be implicated as a causal factor in part of the familial cases grouped in the heterogeneous class of non BRCA1 or BRCA2-mutant cases (BRCAx). To validate this hypothesis, the study should be extended to a larger cohort of ER-negative cases, including those belonging to the BRCAx class. PMID:24475217

  7. Synthetic lethality between CCNE1 amplification and loss of BRCA1.

    PubMed

    Etemadmoghadam, Dariush; Weir, Barbara A; Au-Yeung, George; Alsop, Kathryn; Mitchell, Gillian; George, Joshy; Davis, Sally; D'Andrea, Alan D; Simpson, Kaylene; Hahn, William C; Bowtell, David D L

    2013-11-26

    High-grade serous ovarian cancers (HGSCs) are characterized by a high frequency of TP53 mutations, BRCA1/2 inactivation, homologous recombination dysfunction, and widespread copy number changes. Cyclin E1 (CCNE1) gene amplification has been reported to occur independently of BRCA1/2 mutation, and it is associated with primary treatment failure and reduced patient survival. Insensitivity of CCNE1-amplified tumors to platinum cross-linking agents may be partly because of an intact BRCA1/2 pathway. Both BRCA1/2 dysfunction and CCNE1 amplification are known to promote genomic instability and tumor progression. These events may be mutually exclusive, because either change provides a path to tumor development, with no selective advantage to having both mutations. Using data from a genome-wide shRNA synthetic lethal screen, we show that BRCA1 and members of the ubiquitin pathway are selectively required in cancers that harbor CCNE1 amplification. Furthermore, we show specific sensitivity of CCNE1-amplified tumor cells to the proteasome inhibitor bortezomib. These findings provide an explanation for the observed mutual exclusivity of CCNE1 amplification and BRCA1/2 loss in HGSC and suggest a unique therapeutic approach for treatment-resistant CCNE1-amplified tumors. PMID:24218601

  8. Prevalence of BRCA1 and BRCA2 mutations in unselected breast cancer patients from medellín, Colombia

    PubMed Central

    2014-01-01

    Background Approximately 5% of all breast cancers can be attributed to a mutation in the BRCA1 or BRCA2 gene. The genetic component of breast cancer in Colombia has been, for the most part, studied on cases from the Bogota region. Five different founder mutations were in two studies of breast cancer patients in the Bogota region. It is important that the frequency of mutations be established among unselected cases of breast cancer of other regions of Colombia in order to estimate the genetic burden of this cancer in Colombia and to plan genetic services. The aim of this study was to establish the mutation frequencies of the BRCA genes in breast cancer patients unselected for family history or age, from Medellin, Colombia. Methods We enrolled 280 unselected women with breast cancer from a large public hospital in Medellin, Colombia. A detailed family history from each patient and a blood sample was obtained and processed for DNA analysis. Mutations in BRCA1 and BRCA2 were sought using a combination of techniques including a panel of recurrent Hispanic BRCA mutations which consists of fifty BRCA1 mutations and forty-six BRCA2 mutations, including the five recurrent Colombian BRCA mutations. All mutations were confirmed by direct sequencing. Results Genetic testing was successfully completed for 244 of the 280 cases (87%). Among the 244 cases, three deleterious mutations were identified (two in BRCA1 and one in BRCA2) representing 1.2% of the total. The average age of breast cancer in the mutation-positive cases was 34 years. The two BRCA1 mutations were known founder mutations (3450del4 in exon 11 and A1708E in exon 18). The BRCA2 mutation was in exon 11 (5844del5) and has not been previously reported in individuals of Colombian descent. Among the three mutation-positive families was a breast cancer family and two families with no history of breast or ovarian cancer. Conclusion The frequency of BRCA mutations in unselected breast cancer cases from the Medellin region

  9. Screening of BRCA1/2 Mutations Using Direct Sequencing in Indonesian Familial Breast Cancer Cases.

    PubMed

    Anwar, Sumadi Lukman; Haryono, Samuel J; Aryandono, Teguh; Datasena, I Gusti Bagus

    2016-01-01

    Breast cancer has emerged as the most prevalent cancer among women worldwide, including in Indonesia. The contribution of genes associated with high-risk breast-ovarian cancers, BRCA1 and BRCA2, in the Indonesian population is relatively unknown. We have characterized family history of patients with moderate- to high-risk of breast cancer predisposition in 26 unrelated cases from Indonesia for BRCA1/2 mutation analyses using direct sequencing. Known deleterious mutations were not found in either BRCA1 or BRCA2 genes. Seven variants in BRCA2 were documented in 10 of 26 patients (38%). All variants were categorized as unclassified (VUSs). Two synonymous variants, c.3623A>G and c.4035T>C, were found in 5 patients. One variant, c4600T>C, was found in a 38 year old woman with a family history of breast cancer. We have found 4 novel variants in BRCA2 gene including c.6718C>G, c.3281A>G, c.10176C>G, and c4490T>C in 4 unrelated patients, all of them having a positive family history of breast cancer. In accordance to other studies in Asian population, our study showed more frequent variants in BRCA2 compared to BRCA1. Further studies involving larger numbers of hereditary breast cancer patients are required to reveal contribution of BRCA1/2 mutations and/or other predisposing genes among familial breast cancer patients in Indonesia. PMID:27221885

  10. Contribution of BRCA1 and BRCA2 Germline Mutations to Early Algerian Breast Cancer

    PubMed Central

    Henouda, Sarra; Bensalem, Assia; Reggad, Rym; Serrar, Nedda; Rouabah, Leila; Pujol, Pascal

    2016-01-01

    Breast cancer is the most common female malignancy and the leading cancer mortality cause among Algerian women. Germline mutations in the BRCA1 and BRCA2 genes in patients with early-onset breast cancer have not been clearly identified within the Algerian population. It is necessary to study the BRCA1/2 genes involvement in the Algerian breast cancer occurrence. We performed this study to define germline mutations in BRCA1/2 and their implication in breast cancer among young women from eastern Algeria diagnosed or treated with primary invasive breast cancer at the age of 40 or less who were referred to Anti-Cancer Center of Setif, Algeria. Case series were unselected for family history. Eight distinct pathogenic mutations were identified in eight unrelated families. Three deleterious mutations and one large genomic rearrangement involving deletion of exon 2 were found in BRCA1 gene. In addition, four mutations within the BRCA2 gene and one large genomic rearrangement were identified. Novel mutation was found among Algerian population. Moreover, five variants of uncertain clinical significance and favor polymorphisms were identified. Our data suggest that BRCA1/2 mutations are responsible for a significant proportion of breast cancer in Algerian young women. PMID:26997744

  11. Contribution of BRCA1 and BRCA2 Germline Mutations to Early Algerian Breast Cancer.

    PubMed

    Henouda, Sarra; Bensalem, Assia; Reggad, Rym; Serrar, Nedda; Rouabah, Leila; Pujol, Pascal

    2016-01-01

    Breast cancer is the most common female malignancy and the leading cancer mortality cause among Algerian women. Germline mutations in the BRCA1 and BRCA2 genes in patients with early-onset breast cancer have not been clearly identified within the Algerian population. It is necessary to study the BRCA1/2 genes involvement in the Algerian breast cancer occurrence. We performed this study to define germline mutations in BRCA1/2 and their implication in breast cancer among young women from eastern Algeria diagnosed or treated with primary invasive breast cancer at the age of 40 or less who were referred to Anti-Cancer Center of Setif, Algeria. Case series were unselected for family history. Eight distinct pathogenic mutations were identified in eight unrelated families. Three deleterious mutations and one large genomic rearrangement involving deletion of exon 2 were found in BRCA1 gene. In addition, four mutations within the BRCA2 gene and one large genomic rearrangement were identified. Novel mutation was found among Algerian population. Moreover, five variants of uncertain clinical significance and favor polymorphisms were identified. Our data suggest that BRCA1/2 mutations are responsible for a significant proportion of breast cancer in Algerian young women. PMID:26997744

  12. Cell cycle-dependent inhibition of 53BP1 signaling by BRCA1

    PubMed Central

    Feng, Lin; Li, Nan; Li, Yujing; Wang, Jiadong; Gao, Min; Wang, Wenqi; Chen, Junjie

    2015-01-01

    DNA damage response mediator protein 53BP1 is a key regulator of non-homologous end-joining (NHEJ) repair. 53BP1 protects DNA broken ends from resection by recruiting two downstream factors, RIF1 (RAP1-interacting factor 1) and PTIP (Pax transactivation domain-interacting protein), to double-stranded breaks (DSBs) via ATM (ataxia telangiectasia mutated)-mediated 53BP1 phosphorylation, and competes with BRCA1-mediated homologous recombination (HR) repair in G1 phase. In contrast, BRCA1 antagonizes 53BP1-direct NHEJ repair in S/G2 phases. We and others have found that BRCA1 prevents the translocation of RIF1 to DSBs in S/G2 phases; however, the underlying mechanism remains unclear. Here we show that efficient ATM-dependent 53BP1 phosphorylation is restricted to the G1 phase of the cell cycle, as a consequence RIF1 and PTIP accumulation at DSB sites only occur in G1 phase. Mechanistically, both BRCT and RING domains of BRCA1 are required for the inhibition of 53BP1 phosphorylation in S and G2 phases. Thus, our findings reveal how BRCA1 antagonizes 53BP1 signaling to ensure that HR repair is the dominant repair pathway in S/G2 phases.

  13. SERS gene probe for DNA diagnostics

    NASA Astrophysics Data System (ADS)

    Stokes, David L.; Allain, Leonardo R.; Isola, Narayana R.; Vo-Dinh, Tuan

    2003-07-01

    We describe the development of a surface-enhanced Raman scattering gene (SERGen) probe technology for rapid screening for diseases and pathogens through DNA hybridization assays. The technology combines the use of gene probes labeled with SERS-active markers, and nanostructured metallic platforms for inducing the SERS effect. As a result, SERGen-based methods can offer the spectral selectivity and sensitivity of SERS as well as the molecular specificity of DNA sequence hybridization. Furthermore, these new probe s preclude the use of radioactive labels. As illustrated herein, SERGen probes have been used as primers in polymerase chain reaction (PCR) amplifications of specific DNA sequences, hence further boosting the sensitivity of the technology. We also describe several approaches to developing SERS-active DNA assay platforms, addressing the challenges of making the SERGen technology accessible and practical for clinical settings. The usefulness of the SERGen approach has been demonstrated in the detection of HIV, BRCA1 breast cancer, and BAX genes. There is great potential for the use of numerous SERGen probes for multiplexed detection of multiple biological targets.

  14. Variations in the NBN/NBS1 gene and the risk of breast cancer in non-BRCA1/2 French Canadian families with high risk of breast cancer

    PubMed Central

    2009-01-01

    Background The Nijmegen Breakage Syndrome is a chromosomal instability disorder characterized by microcephaly, growth retardation, immunodeficiency, and increased frequency of cancers. Familial studies on relatives of these patients indicated that they also appear to be at increased risk of cancer. Methods In a candidate gene study aiming at identifying genetic determinants of breast cancer susceptibility, we undertook the full sequencing of the NBN gene in our cohort of 97 high-risk non-BRCA1 and -BRCA2 breast cancer families, along with 74 healthy unrelated controls, also from the French Canadian population. In silico programs (ESEfinder, NNSplice, Splice Site Finder and MatInspector) were used to assess the putative impact of the variants identified. The effect of the promoter variant was further studied by luciferase gene reporter assay in MCF-7, HEK293, HeLa and LNCaP cell lines. Results Twenty-four variants were identified in our case series and their frequency was further evaluated in healthy controls. The potentially deleterious p.Ile171Val variant was observed in one case only. The p.Arg215Trp variant, suggested to impair NBN binding to histone γ-H2AX, was observed in one breast cancer case and one healthy control. A promoter variant c.-242-110delAGTA displayed a significant variation in frequency between both sample sets. Luciferase reporter gene assay of the promoter construct bearing this variant did not suggest a variation of expression in the MCF-7 breast cancer cell line, but indicated a reduction of luciferase expression in both the HEK293 and LNCaP cell lines. Conclusion Our analysis of NBN sequence variations indicated that potential NBN alterations are present, albeit at a low frequency, in our cohort of high-risk breast cancer cases. Further analyses will be needed to fully ascertain the exact impact of those variants on breast cancer susceptibility, in particular for variants located in NBN promoter region. PMID:19523210

  15. BRCA1-like profile predicts benefit of tandem high dose epirubicin-cyclophospamide-thiotepa in high risk breast cancer patients randomized in the WSG-AM01 trial.

    PubMed

    Schouten, Philip C; Gluz, Oleg; Harbeck, Nadia; Mohrmann, Svjetlana; Diallo-Danebrock, Raihana; Pelz, Enrico; Kruizinga, Janneke; Velds, Arno; Nieuwland, Marja; Kerkhoven, Ron M; Liedtke, Cornelia; Frick, Markus; Kates, Ronald; Linn, Sabine C; Nitz, Ulrike; Marme, Frederik

    2016-08-15

    BRCA1 is an important protein in the repair of DNA double strand breaks (DSBs), which are induced by alkylating chemotherapy. A BRCA1-like DNA copy number signature derived from tumors with a BRCA1 mutation is indicative for impaired BRCA1 function and associated with good outcome after high dose (HD) and tandem HD DSB inducing chemotherapy. We investigated whether BRCA1-like status was a predictive biomarker in the WSG AM 01 trial. WSG AM 01 randomized high-risk breast cancer patients to induction (2× epirubicin-cyclophosphamide) followed by tandem HD chemotherapy with epirubicin, cyclophosphamide and thiotepa versus dose dense chemotherapy (4× epirubicin-cyclophospamide followed by 3× cyclophosphamide-methotrexate-5-fluorouracil). We generated copy number profiles for 143 tumors and classified them as being BRCA1-like or non-BRCA1-like. Twenty-six out of 143 patients were BRCA1-like. BRCA1-like status was associated with high grade and triple negative tumors. With regard to event-free-survival, the primary endpoint of the trial, patients with a BRCA1-like tumor had a hazard rate of 0.2, 95% confidence interval (CI): 0.07-0.63, p = 0.006. In the interaction analysis, the combination of BRCA1-like status and HD chemotherapy had a hazard rate of 0.19, 95% CI: 0.067-0.54, p = 0.003. Similar results were observed for overall survival. These findings suggest that BRCA1-like status is a predictor for benefit of tandem HD chemotherapy with epirubicin-thiotepa-cyclophosphamide. PMID:26946057

  16. Genetic Mapping of the BRCA1 Region on Chromosome 17q21

    PubMed Central

    Albertsen, Hans; Plaetke, Rosemarie; Ballard, Linda; Fujimoto, Esther; Connolly, Judith; Lawrence, Elizabeth; Rodriguez, Pilar; Robertson, Margaret; Bradley, Paige; Milner, Bruce; Fuhrman, David; Marks, Andy; Sargent, Robert; Cartwright, Peter; Matsunami, Nori; White, Ray

    1994-01-01

    Chromosome 17q21 harbors a gene (BRCA1) associated with a hereditary form of breast cancer. As a step toward identification of this gene itself we developed a number of simple-sequence-repeat (SSR) markers for chromosome 17 and constructed a high-resolution genetic map of a 40-cM region around 17q21. As part of this effort we captured genotypes from five of the markers by using an ABI sequencing instrument and stored them in a locally developed database, as a step toward automated genotyping. In addition, YACs that physically link some of the SSR markers were identified. The results provided by this study should facilitate physical mapping of the BRCA1 region and isolation of the BRCA1 gene. ImagesFigure 2Figure 1 PMID:8116621

  17. Identification of BRCA1 missense substitutions that confer partial functional activity: potential moderate risk variants?

    PubMed Central

    Lovelock, Paul K; Spurdle, Amanda B; Mok, Myth TS; Farrugia, Daniel J; Lakhani, Sunil R; Healey, Sue; Arnold, Stephen; Buchanan, Daniel; Investigators, kConFab; Couch, Fergus J; Henderson, Beric R; Goldgar, David E; Tavtigian, Sean V; Chenevix-Trench, Georgia; Brown, Melissa A

    2007-01-01

    Introduction Many of the DNA sequence variants identified in the breast cancer susceptibility gene BRCA1 remain unclassified in terms of their potential pathogenicity. Both multifactorial likelihood analysis and functional approaches have been proposed as a means to elucidate likely clinical significance of such variants, but analysis of the comparative value of these methods for classifying all sequence variants has been limited. Methods We have compared the results from multifactorial likelihood analysis with those from several functional analyses for the four BRCA1 sequence variants A1708E, G1738R, R1699Q, and A1708V. Results Our results show that multifactorial likelihood analysis, which incorporates sequence conservation, co-inheritance, segregation, and tumour immunohistochemical analysis, may improve classification of variants. For A1708E, previously shown to be functionally compromised, analysis of oestrogen receptor, cytokeratin 5/6, and cytokeratin 14 tumour expression data significantly strengthened the prediction of pathogenicity, giving a posterior probability of pathogenicity of 99%. For G1738R, shown to be functionally defective in this study, immunohistochemistry analysis confirmed previous findings of inconsistent 'BRCA1-like' phenotypes for the two tumours studied, and the posterior probability for this variant was 96%. The posterior probabilities of R1699Q and A1708V were 54% and 69%, respectively, only moderately suggestive of increased risk. Interestingly, results from functional analyses suggest that both of these variants have only partial functional activity. R1699Q was defective in foci formation in response to DNA damage and displayed intermediate transcriptional transactivation activity but showed no evidence for centrosome amplification. In contrast, A1708V displayed an intermediate transcriptional transactivation activity and a normal foci formation response in response to DNA damage but induced centrosome amplification. Conclusion

  18. Detection of BRCA1 and BRCA2 germline mutations in Japanese population using next-generation sequencing

    PubMed Central

    Hirotsu, Yosuke; Nakagomi, Hiroshi; Sakamoto, Ikuko; Amemiya, Kenji; Mochizuki, Hitoshi; Omata, Masao

    2015-01-01

    Tumor suppressor genes BRCA1 and BRCA2 are the two main breast and ovarian cancer susceptibility genes, and their genetic testing has been used to evaluate the risk of hereditary breast and ovarian cancer (HBOC). While several studies have reported the prevalence of BRCA1 and BRCA2 mutations in Japanese populations, there is insufficient information about deleterious mutations compared with western countries. Moreover, because many rare variants are found in BRCA1 and BRCA2, both of which encode large proteins, it is difficult to sequence all coding regions using the Sanger method for mutation detection. In this study, therefore, we performed next-generation sequencing (NGS) analysis of the entire coding regions of BRCA1 and BRCA2 in 135 breast and/or ovarian cancer patients. Deleterious BRCA1 and BRCA2 mutations were detected in 10 patients (7.4%) by NGS analysis. Of these, one mutation in BRCA1 and two in BRCA2 had not been reported previously. Furthermore, a BRCA2 mutation found in a proband was also identified in two unaffected relatives. These data suggest the utility of screening BRCA1 and BRCA2 mutations by NGS in clinical diagnosis. PMID:25802882

  19. BRCA1 and BRCA2 mutations in Scotland and Northern Ireland

    PubMed Central

    2003-01-01

    BRCA1 and BRCA2 mutations have been identified in 107 families in Scotland and Northern Ireland. Ninety-seven of these families had been referred to regional cancer genetics centres and a further 10 were identified from a sequential series of male breast cancers treated in Edinburgh. Fifty-nine of the families had a mutation in BRCA1 and 46 in BRCA2. Two families had both. Family trees were extended and cancer diagnoses verified by means of the unusually complete and accessible Scottish and Northern Irish records. Ten specific recurring mutations (five in each gene) accounted for almost half of the total detected, and almost one-quarter were accounted for by just two (BRCA1 2800 delAA and BRCA2 6503 delTT). The prevalence of breast cancer is similar for BRCA1 and BRCA2 mutation families (average 3.7 and 3.6 per family), but the former have a much greater risk of ovarian cancer (average 1.5 and 0.6 per family, respectively). For breast cancer, age of onset tended to be younger in BRCA1 mutation carriers but, for ovarian cancer, there was no difference between BRCA1 and BRCA2 families in mean age at diagnosis. Mutations within the 5′ two-thirds of BRCA1 carry a significantly higher relative risk of ovarian cancer and the same is true for mutations within the central portion of BRCA2 (the ‘OCCR’). In the former case, this appears to be because of differences in absolute risk for both ovarian and breast cancer, while, in the latter, only ovarian cancer risk varies significantly. The findings confirm that founder mutations are present within the Scottish/Northern Irish population and have implications for the organisation of molecular screening services. PMID:12698193

  20. Founding BRCA1 mutations in hereditary breast and ovarian cancer in southern Sweden

    SciTech Connect

    Johannsson, O.; Hakansson, S.; Johannson, U.

    1996-03-01

    Nine different germ-line mutations in the BRCA1 breast and ovarian cancer susceptibility gene were identified in 15 of 47 kindreds from southern Sweden, by use of SSCP and heteroduplex analysis of all exons and flanking intron region and by a protein-truncation test for exon 11, followed by direct sequencing. All but one of the mutations are predicted to give rise to premature translation termination and include seven frameshift insertions or deletions, a nonsense mutation, and a splice acceptor site mutation. The remaining mutation is a missense mutation (Cys61Gly) in the zinc-binding motif. Four novel Swedish founding mutations were identified: the nucleotide 2595 deletion A was found in five families, the C 1806 T nonsense mutation in three families, the 3166 insertion TGAGA in three families, and the nucleotide 1201 deletion 11 in two families. Analysis of the intragenic polymorphism D17S855 supports common origins of the mutations. Eleven of the 15 kindreds manifesting BRCA1 mutations were breast-ovarian cancer families, several of them with a predominant ovarian cancer phenotype. The set of 32 families in which no BRCA1 alterations were detected included 1 breast-ovarian cancer kindred manifesting clear linkage to the BRCA1 region and loss of the wild-type chromosome in associated tumors. Other tumor types found in BRCA1 mutation/haplotype carriers included prostatic, pancreas, skin, and lung cancer, a malignant melanoma, an oligodendroglioma, and a carcinosarcoma. In all, 12 of 16 kindreds manifesting BRCA1 mutation or linkage contained ovarian cancer, as compared with only 6 of the remaining 31 families (P < .001). The present study confirms the involvement of BRCA1 in disease predisposition for a subset of hereditary breast cancer families often characterized by ovarian cancers. 28 refs., 3 figs., 4 tabs.

  1. An Estrogen Receptor-α/p300 Complex Activates the BRCA-1 Promoter at an AP-1 Site That Binds Jun/Fos Transcription Factors: Repressive Effects of p53 on BRCA-1 Transcription1

    PubMed Central

    Jeffy, Brandon D; Hockings, Jennifer K; Kemp, Michael Q; Morgan, Sherif S; Hager, Jill A; Beliakoff, Jason; Whitesell, Luke J; Bowden, G. Timothy; Romagnolo, Donato F

    2005-01-01

    Abstract One of the puzzles in cancer predisposition is that women carrying BRCA-1 mutations preferentially develop tumors in epithelial tissues of the breast and ovary. Moreover, sporadic breast tumors contain lower levels of BRCA-1 in the absence of mutations in the BRCA-1 gene. The problem of tissue specificity requires analysis of factors that are unique to tissues of the breast. For example, the expression of estrogen receptor-α (ERα) is inversely correlated with breast cancer risk, and 90% of BRCA-1 tumors are negative for ERα. Here, we show that estrogen stimulates BRCA-1 promoter activity in transfected cells and the recruitment of ERα and its cofactor p300 to an AP-1 site that binds Jun/Fos transcription factors. The recruitment of ERα/p300 coincides with accumulation in the S-phase of the cell cycle and is antagonized by the antiestrogen tamoxifen. Conversely, we document that overexpression of wild-type p53 prevents the recruitment of ERα to the AP-1 site and represses BRCA-1 promoter activity. Taken together, our findings support a model in which an ERα/AP-1 complex modulates BRCA-1 transcription under conditions of estrogen stimulation. Conversely, the formation of this transcription complex is abrogated in cells overexpressing p53. PMID:16229810

  2. Telomere length shows no association with BRCA1 and BRCA2 mutation status.

    PubMed

    Killick, Emma; Tymrakiewicz, Malgorzata; Cieza-Borrella, Clara; Smith, Paula; Thompson, Deborah J; Pooley, Karen A; Easton, Doug F; Bancroft, Elizabeth; Page, Elizabeth; Leongamornlert, Daniel; Kote-Jarai, Zsofia; Eeles, Rosalind A

    2014-01-01

    This study aimed to determine whether telomere length (TL) is a marker of cancer risk or genetic status amongst two cohorts of BRCA1 and BRCA2 mutation carriers and controls. The first group was a prospective set of 665 male BRCA1/2 mutation carriers and controls (mean age 53 years), all healthy at time of enrollment and blood donation, 21 of whom have developed prostate cancer whilst on study. The second group consisted of 283 female BRCA1/2 mutation carriers and controls (mean age 48 years), half of whom had been diagnosed with breast cancer prior to enrollment. TL was quantified by qPCR from DNA extracted from peripheral blood lymphocytes. Weighted and unweighted Cox regressions and linear regression analyses were used to assess whether TL was associated with BRCA1/2 mutation status or cancer risk. We found no evidence for association between developing cancer or being a BRCA1 or BRCA2 mutation carrier and telomere length. It is the first study investigating TL in a cohort of genetically predisposed males and although TL and BRCA status was previously studied in females our results don't support the previous finding of association between hereditary breast cancer and shorter TL. PMID:24489760

  3. Mutation of the BRCA1 SQ-cluster results in aberrant mitosis, reduced homologous recombination, and a compensatory increase in non-homologous end joining.

    PubMed

    Beckta, Jason M; Dever, Seth M; Gnawali, Nisha; Khalil, Ashraf; Sule, Amrita; Golding, Sarah E; Rosenberg, Elizabeth; Narayanan, Aarthi; Kehn-Hall, Kylene; Xu, Bo; Povirk, Lawrence F; Valerie, Kristoffer

    2015-09-29

    Mutations in the breast cancer susceptibility 1 (BRCA1) gene are catalysts for breast and ovarian cancers. Most mutations are associated with the BRCA1 N- and C-terminal domains linked to DNA double-strand break (DSB) repair. However, little is known about the role of the intervening serine-glutamine (SQ) - cluster in the DNA damage response beyond its importance in regulating cell cycle checkpoints. We show that serine-to-alanine alterations at critical residues within the SQ-cluster known to be phosphorylated by ATM and ATR result in reduced homologous recombination repair (HRR) and aberrant mitosis. While a S1387A BRCA1 mutant - previously shown to abrogate S-phase arrest in response to radiation - resulted in only a modest decrease in HRR, S1387A together with an additional alteration, S1423A (BRCA12P), reduced HRR to vector control levels and similar to a quadruple mutant also including S1457A and S1524A (BRCA14P). These effects appeared to be independent of PALB2. Furthermore, we found that BRCA14P promoted a prolonged and struggling HRR late in the cell cycle and shifted DSB repair from HRR to non-homologous end joining which, in the face of irreparable chromosomal damage, resulted in mitotic catastrophe. Altogether, SQ-cluster phosphorylation is critical for allowing adequate time for completing normal HRR prior to mitosis and preventing cells from entering G1 prematurely resulting in gross chromosomal aberrations. PMID:26320175

  4. Recently-Derived Variants of Brain-Size Genes "ASPM", "MCPH1", "CDK5RAP" and "BRCA1" Not Associated with General Cognition, Reading or Language

    ERIC Educational Resources Information Center

    Bates, Timothy C.; Luciano, Michelle; Lind, Penelope A.; Wright, Margaret J.; Montgomery, Grant W.; Martin, Nicholas G.

    2008-01-01

    Derived changes in genes associated with primary microcephaly (MCPH) have been suggested to be "currently sweeping to fixation" i.e., increasing in frequency in most populations, with the likely outcome that the derived allele will completely displace the ancestral allele over time. Possible causes for this sweep include effects on human reasoning…

  5. The Prognostic Value of BRCA1 mRNA Expression Levels Following Neoadjuvant Chemotherapy in Breast Cancer

    PubMed Central

    Margeli, Mireia; Cirauqui, Beatriz; Castella, Eva; Tapia, Gustavo; Costa, Carlota; Gimenez-Capitan, Ana; Barnadas, Agusti; Ronco, Maria Sanchez; Benlloch, Susana; Taron, Miquel; Rosell, Rafael

    2010-01-01

    Background A fraction of sporadic breast cancers has low BRCA1 expression. BRCA1 mutation carriers are more likely to achieve a pathological complete response with DNA-damage-based chemotherapy compared to non-mutation carriers. Furthermore, sporadic ovarian cancer patients with low levels of BRCA1 mRNA have longer survival following platinum-based chemotherapy than patients with high levels of BRCA1 mRNA. Methodology/Principal Findings Tumor biopsies were obtained from 86 breast cancer patients who were candidates for neoadjuvant chemotherapy, treated with four cycles of neoadjuvant fluorouracil, epirubicin and cyclophosphamide. Estrogen receptor (ER), progesterone receptor (PR), HER2, cytokeratin 5/6 and vimentin were examined by tissue microarray. HER2 were also assessed by chromogenic in situ hybridization, and BRCA1 mRNA was analyzed in a subset of 41 patients for whom sufficient tumor tissue was available by real-time quantitative PCR. Median time to progression was 42 months and overall survival was 55 months. In the multivariate analysis for time to progression and overall survival for 41 patients in whom BRCA1 could be assessed, low levels of BRCA1 mRNA, positive PR and negative lymph node involvement predicted a significantly lower risk of relapse, low levels of BRCA1 mRNA and positive PR were the only variables associated with significantly longer survival. Conclusions/Significance We provide evidence for a major role for BRCA1 mRNA expression as a marker of time to progression and overall survival in sporadic breast cancers treated with anthracycline-based chemotherapy. These findings can be useful for customizing chemotherapy. PMID:20209131

  6. BRCA1 and BRCA2 sequence variations detected with next-generation sequencing in patients with premature ovarian insufficiency

    PubMed Central

    Yılmaz, Nafiye Karakaş; Karagin, Peren Hatice; Terzi, Yunus Kasım; Kahyaoğlu, İnci; Yılmaz, Saynur; Erkaya, Salim; Şahin, Feride İffet

    2016-01-01

    Objective Although the association between BRCA1 and BRCA2 gene mutations and breast and ovarian cancer is known, there is insufficient data about premature ovarian insufficiency (POI). However, several studies have reported that there might be a relationship between POI and BRCA1 and BRCA2 gene mutation. Therefore, in the present study, we aimed to investigate the role of BRCA1 and BRCA2 gene mutations in the etiology of POI in a Turkish population. Material and Methods The cohort was classified into two groups: a study group, consisting of 56 individuals diagnosed with premature ovarian insufficiency (and who were younger than 40 years of age, had an antral follicle count <3–5, and FSH levels >12 IU/I), and a control group, consisting of 45 fertile individuals. A total of 101 individuals were analyzed by next-generation sequencing to detect BRCA1 and BRCA2 gene mutations. Results We detected four new variations (p.T1246N and p.R1835Q in BRCA1 and p.I3312V and IVS-7T>A in BRCA2) that had not been reported before. Conclusion We did not find an association between the BRCA1 and BRCA2 gene mutations and premature ovarian insufficiency. However, larger, functional studies are needed to clarify the association. PMID:27403073

  7. Fine tuning chemotherapy to match BRCA1 status

    PubMed Central

    Price, Melissa; Monteiro, Alvaro N.A.

    2010-01-01

    Targeted cancer therapies have been primarily directed at inhibiting oncogenes that are overexpressed or constitutively active in tumors. It is thought that as the cell’s circuitry gets rewired by the constitutive activation of some pathways it becomes exquisitely dependent on this activity. Tumor cell death normally results from inhibiting constitutively active pathways. The dependence of tumor cells on the activity of these pathways has been called oncogene addiction. Approaches that aim to exploit loss of function, rather than gain of function changes have also become a powerful addition to our arsenal of cancer therapies. In particular, when tumors acquire mutations that disrupt pathways in the DNA damage response they rely on alternative pathways that can be targeted pharmacologically. Here we review the use of BRCA1 as a marker of response to therapy with a particular focus on the use of Cisplatin and PARP inhibitors. We also explore the use of BRCA1 as a marker of response to microtubule inhibitors and how all these approaches will bring us closer to the goal of personalized medicine in cancer treatment. PMID:20510205

  8. Aberrant recombination and repair during immunoglobulin class switching in BRCA1-deficient human B cells

    PubMed Central

    Björkman, Andrea; Qvist, Per; Du, Likun; Bartish, Margarita; Zaravinos, Apostolos; Georgiou, Konstantinos; Børglum, Anders D.; Gatti, Richard A.; Törngren, Therese; Pan-Hammarström, Qiang

    2015-01-01

    Breast cancer type 1 susceptibility protein (BRCA1) has a multitude of functions that contribute to genome integrity and tumor suppression. Its participation in the repair of DNA double-strand breaks (DSBs) during homologous recombination (HR) is well recognized, whereas its involvement in the second major DSB repair pathway, nonhomologous end-joining (NHEJ), remains controversial. Here we have studied the role of BRCA1 in the repair of DSBs in switch (S) regions during immunoglobulin class switch recombination, a physiological, deletion/recombination process that relies on the classical NHEJ machinery. A shift to the use of microhomology-based, alternative end-joining (A-EJ) and increased frequencies of intra-S region deletions as well as insertions of inverted S sequences were observed at the recombination junctions amplified from BRCA1-deficient human B cells. Furthermore, increased use of long microhomologies was found at recombination junctions derived from E3 ubiquitin-protein ligase RNF168-deficient, Fanconi anemia group J protein (FACJ, BRIP1)-deficient, or DNA endonuclease RBBP8 (CtIP)-compromised cells, whereas an increased frequency of S-region inversions was observed in breast cancer type 2 susceptibility protein (BRCA2)-deficient cells. Thus, BRCA1, together with its interaction partners, seems to play an important role in repairing DSBs generated during class switch recombination by promoting the classical NHEJ pathway. This may not only provide a general mechanism underlying BRCA1’s function in maintaining genome stability and tumor suppression but may also point to a previously unrecognized role of BRCA1 in B-cell lymphomagenesis. PMID:25646469

  9. BRCA1, BRCA2, PALB2, and CDKN2A Mutations in Familial Pancreatic Cancer (FPC): A PACGENE Study

    PubMed Central

    Zhen, David B.; Rabe, Kari G.; Gallinger, Steven; Syngal, Sapna; Schwartz, Ann G.; Goggins, Michael G.; Hruban, Ralph H.; Cote, Michele L.; McWilliams, Robert R.; Roberts, Nicholas J.; Cannon-Albright, Lisa A.; Li, Donghui; Moyes, Kelsey; Wenstrup, Richard J.; Hartman, Anne-Renee; Seminara, Daniela; Klein, Alison P.; Petersen, Gloria M.

    2014-01-01

    Purpose Familial Pancreatic Cancer (FPC) kindreds contain at least two affected first-degree relatives (FDR). Comprehensive data are needed to assist clinical risk assessment and genetic testing. Methods Germline DNA samples from 727 unrelated probands with positive family history (521 met criteria for FPC) were CLIA-tested for mutations in BRCA1 and BRCA2 (including analysis of deletions and rearrangements), PALB2, and CDKN2A. We compared prevalence of deleterious mutations between FPC probands and non-FPC probands (kindreds containing at least two affected biologic relatives, but not FDR). We also examined the impact of family history of breast and ovarian cancer and melanoma. Results Prevalence of deleterious mutations (excluding variants of unknown significance) among FPC probands was: BRCA1, 1.2%; BRCA2, 3.7%; PALB2, 0.6%; CDKN2A, 2.5%. Four novel deleterious mutations were detected. FPC probands carry more mutations in the four genes (8.0%) than non-FPC probands (3.5%) (odds ratio=2.40, 95% CI=(1.06, 5.44), p=0.03). The probability of testing positive for deleterious mutations in any of the four genes ranges up to 10.4%, depending upon family history of cancers. BRCA2 and CDKN2A account for the majority of mutations in FPC. Conclusion Genetic testing of multiple relevant genes in probands with a positive family history is warranted, particularly for FPC. PMID:25356972

  10. The BRCA1-Δ11q Alternative Splice Isoform Bypasses Germline Mutations and Promotes Therapeutic Resistance to PARP Inhibition and Cisplatin.

    PubMed

    Wang, Yifan; Bernhardy, Andrea J; Cruz, Cristina; Krais, John J; Nacson, Joseph; Nicolas, Emmanuelle; Peri, Suraj; van der Gulden, Hanneke; van der Heijden, Ingrid; O'Brien, Shane W; Zhang, Yong; Harrell, Maribel I; Johnson, Shawn F; Candido Dos Reis, Francisco J; Pharoah, Paul D P; Karlan, Beth; Gourley, Charlie; Lambrechts, Diether; Chenevix-Trench, Georgia; Olsson, Håkan; Benitez, Javier J; Greene, Mark H; Gore, Martin; Nussbaum, Robert; Sadetzki, Siegal; Gayther, Simon A; Kjaer, Susanne K; D'Andrea, Alan D; Shapiro, Geoffrey I; Wiest, David L; Connolly, Denise C; Daly, Mary B; Swisher, Elizabeth M; Bouwman, Peter; Jonkers, Jos; Balmaña, Judith; Serra, Violeta; Johnson, Neil

    2016-05-01

    Breast and ovarian cancer patients harboring BRCA1/2 germline mutations have clinically benefitted from therapy with PARP inhibitor (PARPi) or platinum compounds, but acquired resistance limits clinical impact. In this study, we investigated the impact of mutations on BRCA1 isoform expression and therapeutic response. Cancer cell lines and tumors harboring mutations in exon 11 of BRCA1 express a BRCA1-Δ11q splice variant lacking the majority of exon 11. The introduction of frameshift mutations to exon 11 resulted in nonsense-mediated mRNA decay of full-length, but not the BRCA1-Δ11q isoform. CRISPR/Cas9 gene editing as well as overexpression experiments revealed that the BRCA1-Δ11q protein was capable of promoting partial PARPi and cisplatin resistance relative to full-length BRCA1, both in vitro and in vivo Furthermore, spliceosome inhibitors reduced BRCA1-Δ11q levels and sensitized cells carrying exon 11 mutations to PARPi treatment. Taken together, our results provided evidence that cancer cells employ a strategy to remove deleterious germline BRCA1 mutations through alternative mRNA splicing, giving rise to isoforms that retain residual activity and contribute to therapeutic resistance. Cancer Res; 76(9); 2778-90. ©2016 AACR. PMID:27197267

  11. BRCA1 controls homologous recombination at Tus/Ter-stalled mammalian replication forks.

    PubMed

    Willis, Nicholas A; Chandramouly, Gurushankar; Huang, Bin; Kwok, Amy; Follonier, Cindy; Deng, Chuxia; Scully, Ralph

    2014-06-26

    Replication fork stalling can promote genomic instability, predisposing to cancer and other diseases. Stalled replication forks may be processed by sister chromatid recombination (SCR), generating error-free or error-prone homologous recombination (HR) outcomes. In mammalian cells, a long-standing hypothesis proposes that the major hereditary breast/ovarian cancer predisposition gene products, BRCA1 and BRCA2, control HR/SCR at stalled replication forks. Although BRCA1 and BRCA2 affect replication fork processing, direct evidence that BRCA gene products regulate homologous recombination at stalled chromosomal replication forks is lacking, due to a dearth of tools for studying this process. Here we report that the Escherichia coli Tus/Ter complex can be engineered to induce site-specific replication fork stalling and chromosomal HR/SCR in mouse cells. Tus/Ter-induced homologous recombination entails processing of bidirectionally arrested forks. We find that the Brca1 carboxy (C)-terminal tandem BRCT repeat and regions of Brca1 encoded by exon 11-two Brca1 elements implicated in tumour suppression-control Tus/Ter-induced homologous recombination. Inactivation of either Brca1 or Brca2 increases the absolute frequency of 'long-tract' gene conversions at Tus/Ter-stalled forks, an outcome not observed in response to a site-specific endonuclease-mediated chromosomal double-strand break. Therefore, homologous recombination at stalled forks is regulated differently from homologous recombination at double-strand breaks arising independently of a replication fork. We propose that aberrant long-tract homologous recombination at stalled replication forks contributes to genomic instability and breast/ovarian cancer predisposition in BRCA mutant cells. PMID:24776801

  12. Germline BRCA1/2 mutation testing is indicated in every patient with epithelial ovarian cancer: A systematic review.

    PubMed

    Arts-de Jong, Marieke; de Bock, Geertruida H; van Asperen, Christi J; Mourits, Marian J E; de Hullu, Joanne A; Kets, C Marleen

    2016-07-01

    The presence of a germline BRCA1/2 mutation improves options for tailored risk-reducing strategies and treatment in both breast and ovarian cancer patients and their relatives. Currently, referral for germline BRCA1/2 mutation testing of women with epithelial ovarian cancer (EOC) varies widely, based on different criteria, such as age of onset, family history of breast and/or ovarian cancer and histological type of EOC. The overall probability of a germline BRCA1/2 mutation in women with EOC is above 10%, and a substantial part of the germline BRCA1/2 mutation carriers is missed when applying these criteria for referral. Therefore, we strongly recommend referral of all women with EOC for genetic counselling and DNA analysis. PMID:27209246

  13. A Comprehensive Focus on Global Spectrum of BRCA1 and BRCA2 Mutations in Breast Cancer

    PubMed Central

    Karami, Fatemeh; Mehdipour, Parvin

    2013-01-01

    Breast cancer (BC) is the most common cancer of women all over the world. BRCA1 and BRCA2 gene mutations comprise the most important genetic susceptibility of BC. Except for few common mutations, the spectrum of BRCA1 and BRCA2 mutations is heterogeneous in diverse populations. 185AGdel and 5382insC are the most important BRCA1 and BRCA2 alterations which have been encountered in most of the populations. After those Ashkenazi founder mutations, 300T>G also demonstrated sparse frequency in African American and European populations. This review affords quick access to the most frequent alterations among various populations which could be helpful in BRCA screening programs. PMID:24312913

  14. Multifactorial Likelihood Assessment of BRCA1 and BRCA2 Missense Variants Confirms That BRCA1:c.122A>G(p.His41Arg) Is a Pathogenic Mutation

    PubMed Central

    Whiley, Phillip J.; Parsons, Michael T.; Leary, Jennifer; Tucker, Kathy; Warwick, Linda; Dopita, Belinda; Thorne, Heather; Lakhani, Sunil R.; Goldgar, David E.; Brown, Melissa A.; Spurdle, Amanda B.

    2014-01-01

    Rare exonic, non-truncating variants in known cancer susceptibility genes such as BRCA1 and BRCA2 are problematic for genetic counseling and clinical management of relevant families. This study used multifactorial likelihood analysis and/or bioinformatically-directed mRNA assays to assess pathogenicity of 19 BRCA1 or BRCA2 variants identified following patient referral to clinical genetic services. Two variants were considered to be pathogenic (Class 5). BRCA1:c.4484G> C(p.Arg1495Thr) was shown to result in aberrant mRNA transcripts predicted to encode truncated proteins. The BRCA1:c.122A>G(p.His41Arg) RING-domain variant was found from multifactorial likelihood analysis to have a posterior probability of pathogenicity of 0.995, a result consistent with existing protein functional assay data indicating lost BARD1 binding and ubiquitin ligase activity. Of the remaining variants, seven were determined to be not clinically significant (Class 1), nine were likely not pathogenic (Class 2), and one was uncertain (Class 3).These results have implications for genetic counseling and medical management of families carrying these specific variants. They also provide additional multifactorial likelihood variant classifications as reference to evaluate the sensitivity and specificity of bioinformatic prediction tools and/or functional assay data in future studies. PMID:24489791

  15. Breast Cancer 1 (BrCa1) May Be behind Decreased Lipogenesis in Adipose Tissue from Obese Subjects

    PubMed Central

    Ortega, Francisco J.; Moreno-Navarrete, José M.; Mayas, Dolores; García-Santos, Eva; Gómez-Serrano, María; Rodriguez-Hermosa, José I.; Ruiz, Bartomeu; Ricart, Wifredo; Tinahones, Francisco J.; Frühbeck, Gema; Peral, Belen; Fernández-Real, José M.

    2012-01-01

    Context Expression and activity of the main lipogenic enzymes is paradoxically decreased in obesity, but the mechanisms behind these findings are poorly known. Breast Cancer 1 (BrCa1) interacts with acetyl-CoA carboxylase (ACC) reducing the rate of fatty acid biosynthesis. In this study, we aimed to evaluate BrCa1 in human adipose tissue according to obesity and insulin resistance, and in vitro cultured adipocytes. Research Design and Methods BrCa1 gene expression, total and phosphorylated (P-) BrCa1, and ACC were analyzed in adipose tissue samples obtained from a total sample of 133 subjects. BrCa1 expression was also evaluated during in vitro differentiation of human adipocytes and 3T3-L1 cells. Results BrCa1 gene expression was significantly up-regulated in both omental (OM; 1.36-fold, p = 0.002) and subcutaneous (SC; 1.49-fold, p = 0.001) adipose tissue from obese subjects. In parallel with increased BrCa1 mRNA, P-ACC was also up-regulated in SC (p = 0.007) as well as in OM (p = 0.010) fat from obese subjects. Consistent with its role limiting fatty acid biosynthesis, both BrCa1 mRNA (3.5-fold, p<0.0001) and protein (1.2-fold, p = 0.001) were increased in pre-adipocytes, and decreased during in vitro adipogenesis, while P-ACC decreased during differentiation of human adipocytes (p = 0.005) allowing lipid biosynthesis. Interestingly, BrCa1 gene expression in mature adipocytes was restored by inflammatory stimuli (macrophage conditioned medium), whereas lipogenic genes significantly decreased. Conclusions The specular findings of BrCa1 and lipogenic enzymes in adipose tissue and adipocytes reported here suggest that BrCa1 might help to control fatty acid biosynthesis in adipocytes and adipose tissue from obese subjects. PMID:22666314

  16. Familial site-specific Ovarian cancer is linked to BRCA1 on 17q12-21

    SciTech Connect

    Steichen-Gersdorf, E.; Gallion, H.H.; Ponder, M.A.; Pye, C.; Mazoyer, S.; Smith, S.A.; Ponder, B.A.J.; Ford, D.; Easton, D.F.; Girodet, C.

    1994-11-01

    In a study of nine families with {open_quotes}site-specific{close_quotes} ovarian cancer (criterion: three or more cases of epithelial ovarian cancer and no cases of breast cancer diagnosed at age <50 years) we have obtained evidence of linkage to the breast-ovarian cancer susceptibility gene, BRCA1 on 17q12-21. If the risk of cancer in these families is assumed to be restricted to the ovary, the best estimate of the proportion of families linked to BRCA1 is .78 (95% confidence interval .32-1.0). If predisposition to both breast and ovarian cancer is assumed, the proportion linked is 1.0 (95% confidence interval .46-1.0). The linkage of familial site-specific ovarian cancer to BRCA1 indicates the possibility of predictive testing in such families; however, this is only appropriate in families where the evidence for linkage to BRCA1 is conclusive. 17 refs., 3 figs., 1 tab.

  17. A critical re-assessment of DNA repair gene promoter methylation in non-small cell lung carcinoma

    PubMed Central

    Do, Hongdo; Wong, Nicholas C.; Murone, Carmel; John, Thomas; Solomon, Benjamin; Mitchell, Paul L.; Dobrovic, Alexander

    2014-01-01

    DNA repair genes that have been inactivated by promoter methylation offer potential therapeutic targets either by targeting the specific repair deficiency, or by synthetic lethal approaches. This study evaluated promoter methylation status for eight selected DNA repair genes (ATM, BRCA1, ERCC1, MGMT, MLH1, NEIL1, RAD23B and XPC) in 56 non-small cell lung cancer (NSCLC) tumours and 11 lung cell lines using the methylation-sensitive high resolution melting (MS-HRM) methodology. Frequent methylation in NEIL1 (42%) and infrequent methylation in ERCC1 (2%) and RAD23B (2%) are reported for the first time in NSCLC. MGMT methylation was detected in 13% of the NSCLCs. Contrary to previous studies, methylation was not detected in ATM, BRCA1, MLH1 and XPC. Data from The Cancer Genome Atlas (TCGA) was consistent with these findings. The study emphasises the importance of using appropriate methodology for accurate assessment of promoter methylation. PMID:24569633

  18. Characteristics of Triple-Negative Breast Cancer in Patients With a BRCA1 Mutation: Results From a Population-Based Study of Young Women

    PubMed Central

    Lee, Eunjung; McKean-Cowdin, Roberta; Ma, Huiyan; Spicer, Darcy V.; Van Den Berg, David; Bernstein, Leslie; Ursin, Giske

    2011-01-01

    Purpose Triple-negative breast cancers (TNBCs) are tumors with low or no expression of estrogen receptor, progesterone receptor, or human epidermal growth factor receptor 2. These tumors have a poor prognosis, remain a clinical challenge, and are more common among women with BRCA1 mutations. We tested whether there are distinguishing features of TNBC after BRCA1 mutation status has been taken into account. Patients and Methods We sequenced BRCA1 and BRCA2 genes in a population-based sample of 1,469 patients with incident breast cancer age 20 to 49 years from Los Angeles County (California). Information on tumor receptor status was available for 1,167 women. Clinical, pathologic, and hormone-related lifestyle characteristics were compared across patient subgroups defined by BRCA1 mutation status and triple-negative receptor status. Results Forty-eight percent of BRCA1 mutation carriers had TNBC compared with only 12% of noncarriers. Within BRCA1 mutation carriers, as well as within noncarriers, triple-negative receptor status was associated with younger age at diagnosis and higher tumor grade. Among women without a BRCA1 mutation, we observed that women with TNBC had higher premenopausal body mass index and earlier age at first full-term pregnancy than those with non-TNBC. Age at menarche and other reproductive factors were not associated with triple-negative status regardless of BRCA1 mutation status. Within BRCA1 mutation carriers, Ashkenazi Jewish women were about five times more likely to have TNBC than non–Ashkenazi Jewish women. Conclusion Our results suggest that among BRCA1 mutation carriers, as among noncarriers, there are unique characteristics associated with the triple-negative subtype. The findings in Ashkenazi Jewish BRCA1 mutation carriers should be confirmed. PMID:22010008

  19. Mutational analysis of BRCA1 and BRCA2 in hereditary breast and ovarian cancer families from Asturias (Northern Spain)

    PubMed Central

    2013-01-01

    Background The prevalence of BRCA1 and BRCA2 mutations in Spain is heterogeneous and varies according to geographical origin of studied families. The contribution of these mutations to hereditary breast and ovarian cancer has not been previously investigated in Asturian populations (Northern Spain). Methods In the present work, 256 unrelated high-risk probands with breast and/or ovarian cancer from families living in Asturias were analyzed for the presence of a BRCA1 or BRCA2 gene mutation from October 2007 to May 2012. The entire coding sequences and each intron/exon boundaries of BRCA1/2 genes were screened both by direct sequencing and Multiplex Ligation-dependent Probe Amplification (MLPA). Results A total of 59 families (23%) were found to carry a pathogenic germ line mutation, 39 in BRCA1 and 20 in BRCA2. Twenty nine additional families (12%) carried an unknown significance variant. We detected 28 distinct pathogenic mutations (16 in BRCA1 and 12 in BRCA2), of which 3 mutations in BRCA1 (c.1674delA, c.1965C>A and c.2900_2901dupCT) and 5 in BRCA2 (c.262_263delCT, c.2095C>T, c.3263dupC, c.4030_4035delinsC, c.8042_8043delCA) had not been previously described. The novel mutations c.2900_2901dupCT in BRCA1 and c.4030_4035delinsC in BRCA2 occurred in 8 and 6 families respectively and clustered in two separated small geographically isolated areas suggesting a founder effect. These 2 mutations, together with the Galician BRCA1 mutation c.211A>G (9 families), and the common BRCA1 mutation c.3331_3334delCAAG (6 families), account for approximately 50% of all affected families. By contrast, very frequent mutations in other Spanish series such as the BRCA1 Ashkenazi founder mutation c.68_69delAG, was found in only one family. Conclusions In this study we report the BRCA1 and BRCA2 spectrum of mutations and their geographical distribution in Asturias, which largely differ from other areas of Spain. Our findings may help design a first step recurrent mutation panel for

  20. BRCA1 and BRCA2 rearrangements in Brazilian individuals with Hereditary Breast and Ovarian Cancer Syndrome

    PubMed Central

    Ewald, Ingrid Petroni; Cossio, Silvia Liliana; Palmero, Edenir Inez; Pinheiro, Manuela; Nascimento, Ivana Lucia de Oliveira; Machado, Taisa Manuela Bonfim; Sandes, Kiyoko Abe; Toralles, Betânia; Garicochea, Bernardo; Izetti, Patricia; Pereira, Maria Luiza Saraiva; Bock, Hugo; Vargas, Fernando Regla; Moreira, Miguel Ângelo Martins; Peixoto, Ana; Teixeira, Manuel R.; Ashton-Prolla, Patricia

    2016-01-01

    Abstract Approximately 5-10% of breast cancers are caused by germline mutations in high penetrance predisposition genes. Among these, BRCA1 and BRCA2, which are associated with the Hereditary Breast and Ovarian Cancer (HBOC) syndrome, are the most frequently affected genes. Recent studies confirm that gene rearrangements, especially in BRCA1, are responsible for a significant proportion of mutations in certain populations. In this study we determined the prevalence of BRCA rearrangements in 145 unrelated Brazilian individuals at risk for HBOC syndrome who had not been previously tested for BRCA mutations. Using Multiplex Ligation-dependent Probe Amplification (MLPA) and a specific PCR-based protocol to identify a Portuguese founder BRCA2 mutation, we identified two (1,4%) individuals with germline BRCA1 rearrangements (c.547+240_5193+178del and c.4675+467_5075-990del) and three probands with the c.156_157insAlu founder BRCA2 rearrangement. Furthermore, two families with false positive MLPA results were shown to carry a deleterious point mutation at the probe binding site. This study comprises the largest Brazilian series of HBOC families tested for BRCA1 and BRCA2 rearrangements to date and includes patients from three regions of the country. The overall observed rearrangement frequency of 3.44% indicates that rearrangements are relatively uncommon in the admixed population of Brazil. PMID:27303907

  1. BRCA1 and BRCA2 rearrangements in Brazilian individuals with Hereditary Breast and Ovarian Cancer Syndrome.

    PubMed

    Ewald, Ingrid Petroni; Cossio, Silvia Liliana; Palmero, Edenir Inez; Pinheiro, Manuela; Nascimento, Ivana Lucia de Oliveira; Machado, Taisa Manuela Bonfim; Sandes, Kiyoko Abe; Toralles, Betânia; Garicochea, Bernardo; Izetti, Patricia; Pereira, Maria Luiza Saraiva; Bock, Hugo; Vargas, Fernando Regla; Moreira, Miguel Ângelo Martins; Peixoto, Ana; Teixeira, Manuel R; Ashton-Prolla, Patricia

    2016-01-01

    Approximately 5-10% of breast cancers are caused by germline mutations in high penetrance predisposition genes. Among these, BRCA1 and BRCA2, which are associated with the Hereditary Breast and Ovarian Cancer (HBOC) syndrome, are the most frequently affected genes. Recent studies confirm that gene rearrangements, especially in BRCA1, are responsible for a significant proportion of mutations in certain populations. In this study we determined the prevalence of BRCA rearrangements in 145 unrelated Brazilian individuals at risk for HBOC syndrome who had not been previously tested for BRCA mutations. Using Multiplex Ligation-dependent Probe Amplification (MLPA) and a specific PCR-based protocol to identify a Portuguese founder BRCA2 mutation, we identified two (1,4%) individuals with germline BRCA1 rearrangements (c.547+240_5193+178del and c.4675+467_5075-990del) and three probands with the c.156_157insAlu founder BRCA2 rearrangement. Furthermore, two families with false positive MLPA results were shown to carry a deleterious point mutation at the probe binding site. This study comprises the largest Brazilian series of HBOC families tested for BRCA1 and BRCA2 rearrangements to date and includes patients from three regions of the country. The overall observed rearrangement frequency of 3.44% indicates that rearrangements are relatively uncommon in the admixed population of Brazil. PMID:27303907

  2. TUSC4 functions as a tumor suppressor by regulating BRCA1 stability.

    PubMed

    Peng, Yang; Dai, Hui; Wang, Edward; Lin, Curtis Chun-Jen; Mo, Wei; Peng, Guang; Lin, Shiaw-Yih

    2015-01-15

    BRCA1 expression is lost frequently in breast cancers in which it promotes malignant development. In the present study, we performed a global expression analysis of breast cancer cells in which the tumor-suppressor candidate gene TUSC4 was silenced to gain insights into its function. TUSC4 silencing affected genes involved in cell cycle and cell death, which have broad reaching influence on cancer development. Most importantly, we found a cluster pattern of gene-expression profiles in TUSC4-silenced cells that defined a homologous recombination (HR) repair defect signature. Mechanistic investigations indicated that TUSC4 protein could physically interact with the E3 ligase Herc2, which prevents BRCA1 degradation through the ubiquitination pathway. TUSC4 silencing enhanced BRCA1 polyubiquitination, leading to its degradation and a marked reduction in HR repair efficiency. Notably, ectopic expression of TUSC4 suppressed the proliferation, invasion, and colony formation of breast cancer cells in vitro and tumorigenesis in vivo. Furthermore, TUSC4 silencing was sufficient to transform normal mammary epithelial cells and to enhance sensitivity to PARP inhibitors. Our results provide a set of genetic and biologic proofs that TUSC4 functions as a bona fide tumor suppressor by regulating the protein stability and function of BRCA1 in breast cancer. PMID:25480944

  3. A Common Region of Deletion on Chromosome 17q in Both Sporadic and Familial Epithelial Ovarian Tumors Distal to BRCA1

    PubMed Central

    Godwin, Andrew K.; Vanderveer, Lisa; Schultz, David C.; Lynch, Henry T.; Altomare, Deborah A.; Buetow, Kenneth H.; Daly, Mary; Getts, Lori A.; Masny, Agnes; Rosenblum, Norman; Hogan, Michael; Ozols, Robert F.; Hamilton, Thomas C.

    1994-01-01

    Linkage analysis in familial breast and ovarian cancer and studies of allelic deletion in sporadic ovarian tumors have identified a region on chromosome 17q containing a candidate tumor-suppressor gene (referred to as BRCA1) of likely importance in ovarian carcinogenesis. We have examined normal and tumor DNA samples from 32 patients with sporadic and 8 patients with familial forms of the disease, for loss of heterozygosity (LOH) at 21 loci on chromosome 17 (7 on 17p and 14 on 17q). LOH on 17p was 55% (22/40) for informative 17pl3.1 and 17pl3.3 markers. When six polymorphic markers flanking the familial breast/ovarian cancer susceptibility locus on 17ql2-q21 were used, LOH was 58% (23/40), with one tumor showing telomeric retention. Evaluation of a set of markers positioned telomeric to BRCA1 resulted in the highest degree of LOH, 73% (29/40), indicating that a candidate locus involved in ovarian cancer may reside distal to BRCA1. Five of the tumors demonstrating allelic loss for 17q markers were from individuals with a strong family history of breast and ovarian cancer. More important, two of these tumors (unique patient number [UPN] 57 and UPN 79) retained heterozygosity for all informative markers spanning the BRCA1 locus but showed LOH at loci distal to but not including the anonymous markers CMM86 (D17S74) and 42D6 (D17S588), respectively. Deletion mapping of seven cases (two familial and five sporadic) showing limited LOH on 17q revealed a common region of deletion, distal to GH and proximal to D17S4, that spans −25 cM. These results suggest that a potential tumor-suppressor gene involved in both sporadic and familial ovarian cancer may reside on the distal portion of chromosome 17q and is distinct from the BRCA1 gene. ImagesFigure 1Figure 3 PMID:7942844

  4. Selective Estrogen Receptor Modulators and Pharmacogenomic Variation in ZNF423 Regulation of BRCA1 Expression: Individualized Breast Cancer Prevention

    PubMed Central

    Ingle, James N.; Liu, Mohan; Wickerham, D. Lawrence; Schaid, Daniel J.; Wang, Liewei; Mushiroda, Taisei; Kubo, Michiaki; Costantino, Joseph P.; Vogel, Victor G.; Paik, Soonmyung; Goetz, Matthew P.; Ames, Matthew M.; Jenkins, Gregory D.; Batzler, Anthony; Carlson, Erin E.; Flockhart, David A.; Wolmark, Norman; Nakamura, Yusuke; Weinshilboum, Richard M.

    2013-01-01

    The selective estrogen receptor modulators (SERMs) tamoxifen and raloxifene can reduce the occurrence of breast cancer in high risk women by 50%, but this FDA-approved prevention therapy is not often used. We attempted to identify genetic factors that contribute to variation in SERM breast cancer prevention using DNA from the NSABP P-1 and P-2 breast cancer prevention trials. An initial discovery genome-wide association study identified common single nucleotide polymorphisms (SNPs) in or near the ZNF423 and CTSO genes that were associated with breast cancer risk during SERM therapy. We then showed that both ZNF423 and CTSO participated in the estrogen-dependent induction of BRCA1 expression, in both cases with SNP-dependent variation in induction. ZNF423 appeared to be an estrogen-inducible BRCA1 transcription factor. The odds ratio for differences in breast cancer risk during SERM therapy for subjects homozygous for both protective or both risk alleles for ZNF423 and CTSO was 5.71. PMID:23764426

  5. A BRCA1 deficient, NFκB driven immune signal predicts good outcome in triple negative breast cancer

    PubMed Central

    Buckley, Niamh E.; Haddock, Paula; De Matos Simoes, Ricardo; Parkes, Eileen; Irwin, Gareth; Emmert-Streib, Frank; McQuaid, Stephen; Kennedy, Richard; Mullan, Paul

    2016-01-01

    Triple negative (TNBCs) and the closely related Basal-like (BLBCs) breast cancers are a loosely defined collection of cancers with poor clinical outcomes. Both show strong similarities with BRCA1-mutant breast cancers and BRCA1 dysfunction, or ‘BRCAness’, is observed in a large proportion of sporadic BLBCs. BRCA1 expression and function has been shown in vitro to modulate responses to radiation and chemotherapy. Exploitation of this knowledge in the treatment of BRCA1-mutant patients has had varying degrees of success. This reflects the significant problem of accurately detecting those patients with BRCA1 dysfunction. Moreover, not all BRCA1 mutations/loss of function result in the same histology/pathology or indeed have similar effects in modulating therapeutic responses. Given the poor clinical outcomes and lack of targeted therapy for these subtypes, a better understanding of the biology underlying these diseases is required in order to develop novel therapeutic strategies. We have discovered a consistent NFκB hyperactivity associated with BRCA1 dysfunction as a consequence of increased Reactive Oxygen Species (ROS). This biology is found in a subset of BRCA1-mutant and triple negative breast cancer cases and confers good outcome. The increased NFκB signalling results in an anti-tumour microenvironment which may allow CD8+ cytotoxic T cells to suppress tumour progression. However, tumours lacking this NFκB-driven biology have a more tumour-promoting environment and so are associated with poorer prognosis. Tumour-derived gene expression data and cell line models imply that these tumours may benefit from alternative treatment strategies such as reprogramming the microenvironment and targeting the IGF and AR signalling pathways. PMID:26943587

  6. Genetic Variation at 9p22.2 and Ovarian Cancer Risk for BRCA1 and BRCA2 Mutation Carriers

    PubMed Central

    Kartsonaki, Christiana; Gayther, Simon A.; Pharoah, Paul D. P.; Sinilnikova, Olga M.; Beesley, Jonathan; Chen, Xiaoqing; McGuffog, Lesley; Healey, Sue; Couch, Fergus J.; Wang, Xianshu; Fredericksen, Zachary; Peterlongo, Paolo; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Roversi, Gaia; Barile, Monica; Viel, Alessandra; Allavena, Anna; Ottini, Laura; Papi, Laura; Gismondi, Viviana; Capra, Fabio; Radice, Paolo; Greene, Mark H.; Mai, Phuong L.; Andrulis, Irene L.; Glendon, Gord; Ozcelik, Hilmi; Thomassen, Mads; Gerdes, Anne-Marie; Kruse, Torben A.; Cruger, Dorthe; Jensen, Uffe Birk; Caligo, Maria Adelaide; Olsson, Håkan; Kristoffersson, Ulf; Lindblom, Annika; Arver, Brita; Karlsson, Per; Stenmark Askmalm, Marie; Borg, Ake; Neuhausen, Susan L.; Ding, Yuan Chun; Nathanson, Katherine L.; Domchek, Susan M.; Jakubowska, Anna; Lubiński, Jan; Huzarski, Tomasz; Byrski, Tomasz; Gronwald, Jacek; Górski, Bohdan; Cybulski, Cezary; Dębniak, Tadeusz; Osorio, Ana; Durán, Mercedes; Tejada, Maria-Isabel; Benítez, Javier; Hamann, Ute; Rookus, Matti A.; Verhoef, Senno; Tilanus-Linthorst, Madeleine A.; Vreeswijk, Maaike P.; Bodmer, Danielle; Ausems, Margreet G. E. M.; van Os, Theo A.; Asperen, Christi J.; Blok, Marinus J.; Meijers-Heijboer, Hanne E. J.; Peock, Susan; Cook, Margaret; Oliver, Clare; Frost, Debra; Dunning, Alison M.; Evans, D. Gareth; Eeles, Ros; Pichert, Gabriella; Cole, Trevor; Hodgson, Shirley; Brewer, Carole; Morrison, Patrick J.; Porteous, Mary; Kennedy, M. John; Rogers, Mark T.; Side, Lucy E.; Donaldson, Alan; Gregory, Helen; Godwin, Andrew; Stoppa-Lyonnet, Dominique; Moncoutier, Virginie; Castera, Laurent; Mazoyer, Sylvie; Barjhoux, Laure; Bonadona, Valérie; Leroux, Dominique; Faivre, Laurence; Lidereau, Rosette; Nogues, Catherine; Bignon, Yves-Jean; Prieur, Fabienne; Collonge-Rame, Marie-Agnès; Venat-Bouvet, Laurence; Fert-Ferrer, Sandra; Miron, Alex; Buys, Saundra S.; Hopper, John L.; Daly, Mary B.; John, Esther M.; Terry, Mary Beth; Goldgar, David; Hansen, Thomas v. O.; Jønson, Lars; Ejlertsen, Bent; Agnarsson, Bjarni A.; Offit, Kenneth; Kirchhoff, Tomas; Vijai, Joseph; Dutra-Clarke, Ana V. C.; Przybylo, Jennifer A.; Montagna, Marco; Casella, Cinzia; Imyanitov, Evgeny N.; Janavicius, Ramunas; Blanco, Ignacio; Lázaro, Conxi; Moysich, Kirsten B.; Karlan, Beth Y.; Gross, Jenny; Beattie, Mary S.; Schmutzler, Rita; Wappenschmidt, Barbara; Meindl, Alfons; Ruehl, Ina; Fiebig, Britta; Sutter, Christian; Arnold, Norbert; Deissler, Helmut; Varon-Mateeva, Raymonda; Kast, Karin; Niederacher, Dieter; Gadzicki, Dorothea; Caldes, Trinidad; de la Hoya, Miguel; Nevanlinna, Heli; Aittomäki, Kristiina; Simard, Jacques; Soucy, Penny; Spurdle, Amanda B.; Holland, Helene; Chenevix-Trench, Georgia; Easton, Douglas F.; Antoniou, Antonis C.

    2011-01-01

    Background Germline mutations in the BRCA1 and BRCA2 genes are associated with increased risks of breast and ovarian cancers. Although several common variants have been associated with breast cancer susceptibility in mutation carriers, none have been associated with ovarian cancer susceptibility. A genome-wide association study recently identified an association between the rare allele of the single-nucleotide polymorphism (SNP) rs3814113 (ie, the C allele) at 9p22.2 and decreased risk of ovarian cancer for women in the general population. We evaluated the association of this SNP with ovarian cancer risk among BRCA1 or BRCA2 mutation carriers by use of data from the Consortium of Investigators of Modifiers of BRCA1/2. Methods We genotyped rs3814113 in 10 029 BRCA1 mutation carriers and 5837 BRCA2 mutation carriers. Associations with ovarian and breast cancer were assessed with a retrospective likelihood approach. All statistical tests were two-sided. Results The minor allele of rs3814113 was associated with a reduced risk of ovarian cancer among BRCA1 mutation carriers (per-allele hazard ratio of ovarian cancer = 0.78, 95% confidence interval = 0.72 to 0.85; P = 4.8 × 10-9) and BRCA2 mutation carriers (hazard ratio of ovarian cancer = 0.78, 95% confidence interval = 0.67 to 0.90; P = 5.5 × 10-4). This SNP was not associated with breast cancer risk among either BRCA1 or BRCA2 mutation carriers. BRCA1 mutation carriers with the TT genotype at SNP rs3814113 were predicted to have an ovarian cancer risk to age 80 years of 48%, and those with the CC genotype were predicted to have a risk of 33%. Conclusion Common genetic variation at the 9p22.2 locus was associated with decreased risk of ovarian cancer for carriers of a BRCA1 or BRCA2 mutation. PMID:21169536

  7. The expression of ERCC1 and BRCA1 predicts prognosis of platinum-based chemotherapy in urothelial cancer

    PubMed Central

    Song, Wenhui; Ma, Hongshun

    2016-01-01

    Objective To investigate the expression and clinical significance of ERCC1 and BRCA1 genes in urothelial cancer patients. Methods Forty-two urothelial cancer patients who did not receive platinum-based chemotherapy during January 2009 to May 2013 were enrolled. The expression levels of ERCC1 and BRCA1 were determined by immunohistochemistry and the median survival time (MST) for these patients was calculated. Results ERCC1-positive patients who received oxaliplatin-based chemotherapy had a shorter MST than ERCC1-negative patients (P<0.05), whereas there is no difference of MST between BRCA1-positive and -negative patients. Furthermore, MST in ERCC1 and BRCA1 double-positive patients was shorter than ERCC1 and BRCA1 double-negative patients (P<0.05). The positive expression of ERCC1 had a significant positive correlation with BRCA1 (r=0.313, P=0.044). Conclusion The expression level of ERCC1 may be used as a prognostic marker for urothelial cancer patients who received postoperative adjuvant chemotherapy. PMID:27366083

  8. Selecting for BRCA1 testing using a combination of homogeneous selection criteria and immunohistochemical characteristics of breast cancers

    PubMed Central

    2009-01-01

    Background BRCA1 gene-related tumours are more frequently estrogen receptor (ER) and progesterone receptor (PR) negative with a lower prevalence of human epidermal growth factor receptor 2 (HER2) overexpression or amplification. We evaluated the effectiveness of a combination of homogeneously selected criteria and immunohistochemical (IHC) characteristics of Familial Breast Cancers (FBCs) in detecting BRCA1 mutation carriers. Methods Primary breast tumours from 93 FBC patients defined by specific eligibility criteria, based on personal and familial tumour history, were evaluated by Allred's method. The BRCA1 molecular analysis, including Multiplex Ligation-dependent Probe Amplification (MLPA), was considered as the gold standard assay. Results A total of 10 BRCA1 pathogenetic mutations was found. With the exclusion of the tumours characterized by double positive receptorial status and/or strong HER2 positivity (3+), we identified 22 patients, 10 of whom resulted as BRCA1 mutation carriers. The sensitivity, specificity, positive and negative predictive values were 100%, 83.3%, 45.4% and 100% respectively. Conclusion Our findings suggest that the IHC analysis by Allred's method improves our ability to select patients for BRCA1 testing. PMID:19818148

  9. Association of the BRCA1 promoter polymorphism rs11655505 with the risk of familial breast and/or ovarian cancer.

    PubMed

    Bielinska, Beata; Gaj, Pawel; Kluska, Anna; Nowakowska, Dorota; Balabas, Aneta; Dabrowska, Michalina; Niwinska, Anna; Gruchota, Jakub; Zub, Renata; Skasko, Elzbieta; Steffen, Jan; Ostrowski, Jerzy; Siedlecki, Janusz A

    2013-12-01

    Germline mutations in the BRCA1 tumor suppressor gene predispose affected individuals to breast cancer; however, incomplete cancer penetrance and the presence of phenocopies in BRCA1 families also indicate genetic and environmental modifiers of breast cancer risk. In this study, we have tested the single nucleotide polymorphism rs1655505 of the BRCA1 promoter, as candidate for the modifier of breast cancer risk. The polymorphic variants were genotyped in BRCA1-negative (729), familial breast and/or ovarian cancer cases (FBOC), including cases with a reported maternal history (154), nonfamilal (sporadic) cases (600), hereditary breast/ovarian cases with BRCA1 mutations (190) and population controls (1,590) from Central Poland. An association with the risk of FBOC was observed for the minor (T) allele and (TT) genotype (T: p = 0.006, OR = 1.40, 95% CI = 1.10-1.79; TT: p = 0.001, OR = 2.23, 95% CI = 1.37-3.62) in female cases with a reported maternal history, specifically in women with the onset of disease after 50 years of age (T: p = 0.004, OR = 1.77, 95% CI = 1.20-2.62; TT: p = 0.001, OR = 3.7, 95% CI = 1.62-8.46). The presented evidence suggests a need to conduct larger studies on the association between genetic variations at the BRCA1 promoter and the breast cancer risk, according to maternal/paternal lineage. PMID:23657760

  10. Recurrent BRCA1 and BRCA2 mutations in Mexican women with breast cancer

    PubMed Central

    Torres-Mejía, Gabriela; Royer, Robert; Llacuachaqui, Marcia; Akbari, Mohammad R.; Giuliano, Anna R.; Martínez-Matsushita, Louis; Angeles-Llerenas, Angélica; Ortega-Olvera, Carolina; Ziv, Elad; Lazcano-Ponce, Eduardo; Phelan, Catherine M.; Narod, Steven A.

    2015-01-01

    Background Germline mutations in the BRCA1 and BRCA2 genes confer an estimated 58–80% lifetime risk of breast cancer. In general, screening is done for cancer patients if a relative has been diagnosed with breast or ovarian cancer. There are few data on the prevalence of mutations in these genes in Mexican women with breast cancer and this hampers efforts to develop screening policies in Mexico. Methods We screened 810 unselected women with breast cancer from three cities in Mexico (Mexico City, Veracruz and Monterrey) for mutations in BRCA1 and BRCA2, including a panel of 26 previously reported mutations. Results Thirty-five mutations were identified in 34 women (4.3% of total) including 20 BRCA1 mutations and 15 BRCA2 mutations. Twenty-two of the 35 mutations were recurrent mutations (62.8%). Only five of the 34 mutation carriers had a first-degree relative with breast cancer (three with BRCA1 and two with BRCA2 mutations). Conclusion These results support the rationale for a strategy of screening for recurrent mutations in all women with breast cancer in Mexico, as opposed to restricting screening to those with a sister or mother with breast or ovarian cancer. Impact These results will impact cancer genetic testing in Mexico and the identification of at-risk individuals who will benefit from increased surveillance. PMID:25371446

  11. TGFβ Induces ‘BRCAness’ and Sensitivity to PARP Inhibition in Breast Cancer by Regulating DNA Repair Genes

    PubMed Central

    Liu, Liang; Zhou, Weiying; Cheng, Chun-Ting; Ren, Xiubao; Somlo, George; Fong, Miranda Y.; Chin, Andrew R.; Li, Hui; Yu, Yang; Xu, Yang; O'Connor, Sean Timothy Francis; O'Connor, Timothy R.; Ann, David K.; Stark, Jeremy M.; Wang, Shizhen Emily

    2014-01-01

    Transforming growth factor β (TGFβ) proteins are multitasking cytokines, whose high levels at tumor sites generally correlate with poor prognosis in human cancer patients. Previously it was reported that TGFβ downregulates the expression of ataxia telangiectasia mutated (ATM) and mutS homolog 2 (MSH2) in breast cancer (BC) cells through a miRNA-mediated mechanism. In this study, expression of a panel of DNA repair genes was examined, identifying breast cancer 1, early onset (BRCA1) as a target downregulated by TGFβ through the miR-181 family. Correlations between the expression levels of TGFβ1 and the miR-181/BRCA1 axis were observed in primary breast tumor specimens. By downregulating BRCA1, ATM, and MSH2, TGFβ orchestrates DNA damage response (DDR) in certain BC cells to induce a ‘BRCAness’ phenotype, including impaired DNA repair efficiency and synthetic lethality to the inhibition of poly (ADP-ribose) polymerase (PARP). Xenograft tumors with active TGFβ signaling exhibited resistance to the DNA-damaging agent doxorubicin but increased sensitivity to the PARP inhibitor ABT-888. Combination of doxorubicin with ABT-888 significantly improved the treatment efficacy in TGFβ-active tumors. Thus, TGFβ can induce ‘BRCAness’ in certain BCs carrying wild-type BRCA genes and enhance the responsiveness to PARP inhibition, and the molecular mechanism behind this is characterized. Implications: These findings enable better selection of sporadic breast cancer patients for PARP interventions, which have exhibited beneficial effects in patients carrying BRCA mutations. PMID:25103497

  12. A Macrohistone Variant Links Dynamic Chromatin Compaction to BRCA1-Dependent Genome Maintenance

    PubMed Central

    Khurana, Simran; Kruhlak, Michael J.; Kim, Jeongkyu; Tran, Andy D.; Liu, Jinping; Nyswaner, Katherine; Shi, Lei; Jailwala, Parthav; Sung, Myong-Hee; Hakim, Ofir; Oberdoerffer, Philipp

    2014-01-01

    SUMMARY 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. PMID:25131201

  13. Founder BRCA1 and BRCA2 mutations in French Canadian breast and ovarian cancer families.

    PubMed Central

    Tonin, P N; Mes-Masson, A M; Futreal, P A; Morgan, K; Mahon, M; Foulkes, W D; Cole, D E; Provencher, D; Ghadirian, P; Narod, S A

    1998-01-01

    We have identified four mutations in each of the breast cancer-susceptibility genes, BRCA1 and BRCA2, in French Canadian breast cancer and breast/ovarian cancer families from Quebec. To identify founder effects, we examined independently ascertained French Canadian cancer families for the distribution of these eight mutations. Mutations were found in 41 of 97 families. Six of eight mutations were observed at least twice. The BRCA1 C4446T mutation was the most common mutation found, followed by the BRCA2 8765delAG mutation. Together, these mutations were found in 28 of 41 families identified to have a mutation. The odds of detection of any of the four BRCA1 mutations was 18.7x greater if one or more cases of ovarian cancer were also present in the family. The odds of detection of any of the four BRCA2 mutations was 5.3x greater if there were at least five cases of breast cancer in the family. Interestingly, the presence of a breast cancer case <36 years of age was strongly predictive of the presence of any of the eight mutations screened. Carriers of the same mutation, from different families, shared similar haplotypes, indicating that the mutant alleles were likely to be identical by descent for a mutation in the founder population. The identification of common BRCA1 and BRCA2 mutations will facilitate carrier detection in French Canadian breast cancer and breast/ovarian cancer families. PMID:9792861

  14. Associations of High-Grade Prostate Cancer with BRCA1 and BRCA2 Founder Mutations

    PubMed Central

    Agalliu, Ilir; Gern, Robert; Leanza, Suzanne; Burk, Robert D.

    2013-01-01

    Purpose Protein-truncating mutations in BRCA1 and in particular BRCA2 genes have been associated with prostate cancer. However, there is still uncertainty about the magnitude of association particularly with Gleason score, and family history of prostate, breast, and ovary cancers. Experimental Design To further examine associations between three founder mutations located in BRCA1 (185delAG, 5382insC) or BRCA2 (6174delT) genes and prostate cancer, we conducted a study of 979 prostate cancer cases and 1,251 controls among Ashkenazi Jewish men. Detailed information was obtained on prostate cancer pathology, age at diagnosis, and family history of all cancers. Odds ratios (OR) and 95% confidence intervals (CIs) were estimated using logistic regression models. Results Prostate cancer risk was increased (OR, 1.9; 95% CI 0.9-4.1) for BRCA2 mutation carriers but not for BRCA1 mutation carriers. BRCA2 mutation carriers had an OR of 3.2 (95% CI, 1.4-7.3) for Gleason score of 7 to 10, but no association was observed for Gleason score of <7. Carriers of BRCA1-185delAG mutation also had an OR of 3.5 (95% CI, 1.2-10.3) for Gleason score of ≥7 tumors; however, the association of either BRCA1-185delAG or 5382insC mutation was not statistically significant. Associations between founder mutations and prostate cancer were stronger in men with no first-degree family history of breast and/or ovarian cancers but were unaffected by family history of prostate cancer. Conclusion These results indicate that the BRCA2 founder mutation confers a 3-fold elevated risk of high-grade prostate cancer. Although BRCA1 mutations were not associated with prostate cancer, the BRCA1-185delAG was associated with high Gleason score tumors. These findings should be carefully considered in genetic counseling and/or evaluating therapeutic options. PMID:19188187

  15. Brca1 Mutations Enhance Mouse Reproductive Functions by Increasing Responsiveness to Male-Derived Scent

    PubMed Central

    Liu, Ying; Pike, Malcolm C.; Wu, Nancy; Lin, Yvonne G.; Mucowski, Sara; Punj, Vasu; Tang, Yuan; Yen, Hai-Yun; Stanczyk, Frank Z.; Enbom, Elena; Austria, Theresa; Widschwendter, Martin; Maxson, Robert; Dubeau, Louis

    2015-01-01

    We compared the gene expression profiles of ovarian granulosa cells harboring either mutant or wild type Brca1 to follow up on our earlier observation that absence of a functional Brca1 in these important regulators of menstrual/estrous cycle progression leads to prolongation of the pre-ovulatory phase of the estrous cycle and to increased basal levels of circulating estradiol. Here we show that ovarian granulosa cells from mice carrying a conditional Brca1 gene knockout express substantially higher levels of olfactory receptor mRNA than granulosa cells from wild type littermates. This led us to hypothesize that reproductive functions in mutant female mice might be more sensitive to male-derived scent than in wild type female mice. Indeed, it is well established that isolation from males leads to complete cessation of mouse estrous cycle activity while exposure to olfactory receptor ligands present in male urine leads to resumption of such activity. We found that Brca1-/- female mice rendered anovulatory by unisexual isolation resumed ovulatory activity more rapidly than their wild type littermates when exposed to bedding from cages where males had been housed. The prime mediator of this increased responsiveness appears to be the ovary and not olfactory neurons. This conclusion is supported by the fact that wild type mice in which endogenous ovaries had been replaced by Brca1-deficient ovarian transplants responded to male-derived scent more robustly than mutant mice in which ovaries had been replaced by wild type ovarian transplants. Our findings not only have important implications for our understanding of the influence of olfactory signals on reproductive functions, but also provide insights into mechanisms whereby genetic risk factors for breast and extra uterine Müllerian carcinomas may influence menstrual activity in human, which is itself an independent risk factor for these cancers. PMID:26488398

  16. A YAC-, P1, and cosmid-based physical map of the BRCA1 region on chromosome 17q21

    SciTech Connect

    Couch, F.J.; Castilla, L.H.; Brody, L.C.

    1995-01-01

    A familial early-onset breast cancer gene (BRCA1) has been localized to chromosome 17q21. To characterize this region and to aid in the identification of the BRCA1 gene, a physical map of a region of 1.0-1.5 Mb between the EDH17B1 and the PPY loci on chromosome 17q21 was generated. The physical map is composed of a yeast artificial chromosome (YAC) and P1 phage contig with one gap. The majority of the interval has also been converted to a cosmid contig. Twenty-three PCR-based sequence-tagged sites (STSs) were mapped to these contigs, thereby confirming the order and overlap of individual clones. This complex physical map of the BRCA1 region was used to isolate genes by a number of gene identification techniques and to generate transcript maps of the region. 32 refs., 4 figs.

  17. Common genetic variation at BARD1 is not associated with Breast cancer risk in BRCA1 or BRCA2 mutation carriers

    PubMed Central

    Spurdle, Amanda B.; Marquart, Louise; McGuffog, Lesley; Healey, Sue; Sinilnikova, Olga; Wan, Fei; Chen, Xiaoqing; Beesley, Jonathan; Singer, Christian F; Dressler, Anne-Catharine; Gschwantler-Kaulich, Daphne; Blum, Joanne L.; Tung, Nadine; Weitzel, Jeff; Lynch, Henry; Garber, Judy; Easton, Douglas F.; Peock, Susan; Cook, Margaret; Oliver, Clare T.; Frost, Debra; Conroy, Don; Evans, D. Gareth; Lalloo, Fiona; Eeles, Ros; Izatt, Louise; Davidson, Rosemarie; Chu, Carol; Eccles, Diana; Selkirk, Christina G.; Daly, Mary; Isaacs, Claudine; Stoppa-Lyonnet, Dominique; Sinilnikova, Olga M.; Buecher, Bruno; Belotti, Muriel; Mazoyer, Sylvie; Barjhoux, Laure; Verny-Pierre, Carole; Lasset, Christine; Dreyfus, Hélène; Pujol, Pascal; Collonge-Rame, Marie-Agnès; Rookus, Matti A.; Verhoef, Senno; Kriege, Mieke; Hoogerbrugge, Nicoline; Ausems, Margreet G.E.M.; van Os, Theo A.; Wijnen, Juul; Devilee, Peter; Meijers-Heijboer, Hanne E.J.; Blok, Marinus J.; Heikkinen, Tuomas; Nevanlinna, Heli; Jakubowska, Anna; Lubiński, Jan; Huzarski, Tomasz; Byrski, Tomasz; Durocher, Francine; Couch, Fergus J.; Lindor, Noralane M.; Wang, Xianshu; Thomassen, Mads; Domchek, Susan; Nathanson, Kate; Caligo, MA; Jernström, Helena; Liljegren, Annelie; Ehrencrona, Hans; Karlsson, Per; Ganz, Patricia A.; Olopade, Olufunmilayo I.; Tomlinson, Gail; Neuhausen, Susan; Antoniou, Antonis C.; Chenevix-Trench, Georgia; Rebbeck, Timothy R.

    2011-01-01

    Background Inherited BRCA1 and BRCA2 (BRCA1/2) mutations confer elevated breast cancer risk. Knowledge of factors that can improve breast cancer risk assessment in BRCA1/2 mutation carriers may improve personalized cancer prevention strategies. Methods A cohort of 5,546 BRCA1 and 2,865 BRCA2 mutation carriers was used to evaluate risk of breast cancer associated with BARD1 Cys557Ser. In a second non-independent cohort of 1,537 of BRCA1 and 839 BRCA2 mutation carriers, BARD1 haplotypes were also evaluated. Results The BARD1 Cys557Ser variant was not significantly associated with risk of breast cancer from single SNP analysis, with a pooled effect estimate of 0.90 (95%CI: 0.71-1.15) in BRCA1 carriers and 0.87 (95%CI: 0.59-1.29) in BRCA2 carriers. Further analysis of haplotypes at BARD1 also revealed no evidence that additional common genetic variation not captured by Cys557Ser was associated with breast cancer risk. Conclusion Evidence to date does not support a role for BARD1 variation, including the Cy557Ser variant, as a modifier of risk in BRCA1/2 mutation carriers. Impact Interactors of BRCA1/2 have been implicated as modifiers of BRCA1/2-associated cancer risk. Our finding that BARD1 does not contribute to this risk modification may focus research on other genes that do modify BRCA1/2-associated cancer risk. PMID:21393566

  18. Comprehensive analysis of BRCA1 and BRCA2 germline mutations in a large cohort of 5931 Chinese women with breast cancer.

    PubMed

    Zhang, Juan; Sun, Jie; Chen, Jiuan; Yao, Lu; Ouyang, Tao; Li, Jinfeng; Wang, Tianfeng; Fan, Zhaoqing; Fan, Tie; Lin, Benyao; Xie, Yuntao

    2016-08-01

    We determined the prevalence and characteristics of BRCA1/2 germline mutations in a large cohort of Chinese women with breast cancer. A total of 5931 unselected Chinese women with breast cancer were enrolled in this study and underwent testing for BRCA1/2 mutations. Of these, 543 patients were familial breast cancer, 1033 were early-onset disease (≤40 years) without family history of breast cancer, and 4355 were sporadic breast cancer. In total, 232 patients (3.9 %) carried a BRCA1 or BRCA2 mutation (110 in BRCA1and 122 in BRCA2) in this cohort of 5931 patients. BRCA1/2 mutation rate was 16.9 % (92/543) in familial breast cancers, 5.2 % (54/1033) in early-onset breast cancers (≤40 years), and 2.0 % in sporadic breast cancers (>40 years), respectively. The BRCA1/2 mutation rate was 27.0 % in 111 familial breast cancers diagnosed at and before the age of 40. 41.4 % of mutations in this cohort were specific for Chinese population. Recurrent mutations accounted for 44.8 % of the entire mutations in 2382 cases that BRCA1 and BRCA2 genes were fully sequenced in this study. Both BRCA1 and BRCA2 mutation carriers were significantly more likely to be early-onset and bilateral breast cancers, high-grade cancer, and to have a family history of breast cancer compared with non-carriers. BRCA1 mutation carriers were more likely to be triple-negative cancer than BRCA2 mutation carriers and non-carriers. Our data provide guidelines for Chinese women with breast cancer who should undergo BRCA1/2 genetic testing; additionally, recurrent mutations account for nearly half of the mutations and some of them are specific for Chinese women. PMID:27393621

  19. Candidate genetic modifiers for breast and ovarian cancer risk in BRCA1 and BRCA2 mutation carriers

    PubMed Central

    Peterlongo, Paolo; Chang-Claude, Jenny; Moysich, Kirsten B.; Rudolph, Anja; Schmutzler, Rita K.; Simard, Jacques; Soucy, Penny; Eeles, Rosalind A.; Easton, Douglas F.; Hamann, Ute; Wilkening, Stefan; Chen, Bowang; Rookus, Matti A.; Schmidt, Marjanka K; van der Baan, Frederieke H.; Spurdle, Amanda B.; Walker, Logan C.; Lose, Felicity; Maia, Ana-Teresa; Montagna, Marco; Matricardi, Laura; Lubinski, Jan; Jakubowska, Anna; Gómez Garcia, Encarna B.; Olopade, Olufunmilayo I.; Nussbaum, Robert L.; Nathanson, Katherine L.; Domchek, Susan M.; Rebbeck, Timothy R.; Arun, Banu K.; Karlan, Beth Y.; Orsulic, Sandra; Lester, Jenny; Chung, Wendy K.; Miron, Alex; Southey, Melissa C.; Goldgar, David E.; Buys, Saundra S.; Janavicius, Ramunas; Dorfling, Cecilia M.; van Rensburg, Elizabeth J.; Ding, Yuan Chun; Neuhausen, Susan L.; Hansen, Thomas V. O.; Gerdes, Anne-Marie; Ejlertsen, Bent; Jønson, Lars; Osorio, Ana; Martínez-Bouzas, Cristina; Benitez, Javier; Conway, Edye E.; Blazer, Kathleen R.; Weitzel, Jeffrey N.; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Scuvera, Giulietta; Barile, Monica; Ficarazzi, Filomena; Mariette, Frederique; Fortuzzi, Stefano; Viel, Alessandra; Giannini, Giuseppe; Papi, Laura; Martayan, Aline; Tibiletti, Maria Grazia; Radice, Paolo; Vratimos, Athanassios; Fostira, Florentia; Garber, Judy E.; Donaldson, Alan; Brewer, Carole; Foo, Claire; Evans, D. Gareth R.; Frost, Debra; Eccles, Diana; Brady, Angela; Cook, Jackie; Tischkowitz, Marc; Adlard, Julian; Barwell, Julian; Walker, Lisa; Izatt, Louise; Side, Lucy E.; Kennedy, M. John; Rogers, Mark T.; Porteous, Mary E.; Morrison, Patrick J.; Platte, Radka; Davidson, Rosemarie; Hodgson, Shirley V.; Ellis, Steve; Cole, Trevor; Godwin, Andrew K.; Claes, Kathleen; Van Maerken, Tom; Meindl, Alfons; Gehrig, Andrea; Sutter, Christian; Engel, Christoph; Niederacher, Dieter; Steinemann, Doris; Plendl, Hansjoerg; Kast, Karin; Rhiem, Kerstin; Ditsch, Nina; Arnold, Norbert; Varon-Mateeva, Raymonda; Wappenschmidt, Barbara; Wang-Gohrke, Shan; Bressac-de Paillerets, Brigitte; Buecher, Bruno; Delnatte, Capucine; Houdayer, Claude; Stoppa-Lyonnet, Dominique; Damiola, Francesca; Coupier, Isabelle; Barjhoux, Laure; Venat-Bouvet, Laurence; Golmard, Lisa; Boutry-Kryza, Nadia; Sinilnikova, Olga M.; Caron, Olivier; Pujol, Pascal; Mazoyer, Sylvie; Belotti, Muriel; Piedmonte, Marion; Friedlander, Michael L.; Rodriguez, Gustavo C.; Copeland, Larry J; de la Hoya, Miguel; Segura, Pedro Perez; Nevanlinna, Heli; Aittomäki, Kristiina; van Os, Theo A.M.; Meijers-Heijboer, Hanne E.J.; van der Hout, Annemarie H.; Vreeswijk, Maaike P.G.; Hoogerbrugge, Nicoline; Ausems, Margreet G.E.M.; van Doorn, Helena C.; Collée, J. Margriet; Olah, Edith; Diez, Orland; Blanco, Ignacio; Lazaro, Conxi; Brunet, Joan; Feliubadalo, Lidia; Cybulski, Cezary; Gronwald, Jacek; Durda, Katarzyna; Jaworska-Bieniek, Katarzyna; Sukiennicki, Grzegorz; Arason, Adalgeir; Chiquette, Jocelyne; Teixeira, Manuel R.; Olswold, Curtis; Couch, Fergus J.; Lindor, Noralane M.; Wang, Xianshu; Szabo, Csilla I.; Offit, Kenneth; Corines, Marina; Jacobs, Lauren; Robson, Mark E.; Zhang, Liying; Joseph, Vijai; Berger, Andreas; Singer, Christian F.; Rappaport, Christine; Kaulich, Daphne Geschwantler; Pfeiler, Georg; Tea, Muy-Kheng M.; Phelan, Catherine M.; Greene, Mark H.; Mai, Phuong L.; Rennert, Gad; Mulligan, Anna Marie; Glendon, Gord; Tchatchou, Sandrine; Andrulis, Irene L.; Toland, Amanda Ewart; Bojesen, Anders; Pedersen, Inge Sokilde; Thomassen, Mads; Jensen, Uffe Birk; Laitman, Yael; Rantala, Johanna; von Wachenfeldt, Anna; Ehrencrona, Hans; Askmalm, Marie Stenmark; Borg, Åke; Kuchenbaecker, Karoline B.; McGuffog, Lesley; Barrowdale, Daniel; Healey, Sue; Lee, Andrew; Pharoah, Paul D.P.; Chenevix-Trench, Georgia; Antoniou, Antonis C.; Friedman, Eitan

    2014-01-01

    Background BRCA1 and BRCA2 mutation carriers are at substantially increased risk for developing breast and ovarian cancer. The incomplete penetrance coupled with the variable age at diagnosis in carriers of the same mutation suggests the existence of genetic and non-genetic modifying factors. In this study we evaluated the putative role of variants in many candidate modifier genes. Methods Genotyping data from 15,252 BRCA1 and 8,211 BRCA2 mutation carriers, for known variants (n=3,248) located within or around 445 candidate genes, were available through the iCOGS custom-designed array. Breast and ovarian cancer association analysis was performed within a retrospective cohort approach. Results The observed p-values of association ranged between 0.005-1.000. None of the variants was significantly associated with breast or ovarian cancer risk in either BRCA1 or BRCA2 mutation carriers, after multiple testing adjustments. Conclusion There is little evidence that any of the evaluated candidate variants act as modifiers of breast and/or ovarian cancer risk in BRCA1 or BRCA2 mutation carriers. Impact Genome-wide association studies have been more successful at identifying genetic modifiers of BRCA1/2 penetrance than candidate gene studies. PMID:25336561

  20. Significant clinical impact of recurrent BRCA1 and BRCA2 mutations in Mexico

    PubMed Central

    Villarreal-Garza, Cynthia; Alvarez-Gómez, Rosa María; Pérez-Plasencia, Carlos; Herrera, Luis A.; Herzog, Josef; Castillo, Danielle; Mohar, Alejandro; Castro, Clementina; Gallardo, Lenny N.; Gallardo, Dolores; Santibáñez, Miguel; Blazer, Kathleen R.; Weitzel, Jeffrey N.

    2014-01-01

    Background Frequent recurrent BRCA1 and BRCA2 gene (BRCA) mutations among Hispanics, including a large rearrangement Mexican founder mutation (BRCA1 ex9-12del), suggest that an ancestry-informed BRCA-testing strategy could reduce disparities and promote cancer prevention by enabling economical screening for hereditary breast and ovarian cancer in Mexico. Methods In a multistage approach, 188 cancer cases unselected for family cancer history (92 ovarian cancer and 96 breast cancer) were screened for BRCA mutations using a Hispanic mutation panel (HISPANEL®) of 115 recurrent mutations in a multiplex assay (114 on a mass spectroscopy platform, and a PCR assay for the BRCA1 ex9-12del mutation), followed by sequencing of all BRCA exons and adjacent intronic regions, and BRCA1 multiplex ligation-dependent probe amplification assay (MLPA) for HISPANEL negative cases. BRCA mutation prevalence was calculated and correlated with histology and tumor receptor status, and HISPANEL sensitivity was estimated. Results BRCA mutations were detected in 28% (26/92) of ovarian cancer cases and 15% (14/96) of breast cancer cases overall and 27% (9/33) of triple negative breast cancer. Most breast cancer cases were diagnosed with locally advanced disease. The Mexican founder mutation (BRCA1 ex9-12del) accounted for 35% of the BRCA-associated ovarian cancer cases and 29% of the BRCA-associated breast cancer cases. At 2% of the sequencing and MLPA cost, the HISPANEL detected 68% of all BRCA mutations. Conclusion In this study, we found a remarkably high prevalence of BRCA mutations among ovarian and breast cases not selected for family history, and BRCA1 ex9-12del explained one third of the total. The remarkable frequency of BRCA1 ex9-12del in Mexico City supports a nearby origin of this Mexican founder mutation and may constitute a regional public health problem. The HISPANEL presents a translational opportunity for cost-effective genetic testing to enable breast and ovarian cancer

  1. The Polycomb Group Protein EZH2 Impairs DNA Damage Repair Gene Expression in Human Uterine Fibroids.

    PubMed

    Yang, Qiwei; Nair, Sangeeta; Laknaur, Archana; Ismail, Nahed; Diamond, Michael P; Al-Hendy, Ayman

    2016-03-01

    Uterine fibroids are benign, smooth muscle tumors that occur in approximately 70%-80% of women by age 50 yr. The cellular and molecular mechanism(s) by which uterine fibroids (UFs) develop are not fully understood. Accumulating evidence demonstrates that several genetic abnormalities, including deletions, rearrangements, translocations, as well as mutations, have been found in UFs. These genetic anomalies suggest that low DNA damage repair capacity may be involved in UF formation. The objective of this study was to determine whether expression levels of DNA damage repair-related genes were altered, and how they were regulated in the pathogenesis of UFs. Expression levels of DNA repair-related genes RAD51 and BRCA1 were deregulated in fibroid tissues as compared to adjacent myometrial tissues. Expression levels of chromatin protein enhancer of zeste homolog 2 (EZH2) were higher in a subset of fibroids as compared to adjacent myometrial tissues by both immunohistochemistry and Western blot analysis. Treatment with an inhibitor of EZH2 markedly increased expression levels of RAD51 and BRCA1 in fibroid cells and inhibited cell proliferation paired with cell cycle arrest. Restoring the expression of RAD51 and BRCA1 by treatment with EZH2 inhibitor was dependent on reducing the enrichment of trimethylation of histone 3 lysine 27 epigenetic mark in their promoter regions. This study reveals the important role of EZH2-regulated DNA damage-repair genes via histone methylation in fibroid biology, and may provide novel therapeutic targets for the medical treatment of women with symptomatic UFs. PMID:26888970

  2. Haplotype analysis of the 185delAG BRCA1 mutation in ethnically diverse populations

    PubMed Central

    Laitman, Yael; Feng, Bing-Jian; Zamir, Itay M; Weitzel, Jeffrey N; Duncan, Paul; Port, Danielle; Thirthagiri, Eswary; Teo, Soo-Hwang; Evans, Gareth; Latif, Ayse; Newman, William G; Gershoni-Baruch, Ruth; Zidan, Jamal; Shimon-Paluch, Shani; Goldgar, David; Friedman, Eitan

    2013-01-01

    The 185delAG* BRCA1 mutation is encountered primarily in Jewish Ashkenazi and Iraqi individuals, and sporadically in non-Jews. Previous studies estimated that this is a founder mutation in Jewish mutation carriers that arose before the dispersion of Jews in the Diaspora ∼2500 years ago. The aim of this study was to assess the haplotype in ethnically diverse 185delAG* BRCA1 mutation carriers, and to estimate the age at which the mutation arose. Ethnically diverse Jewish and non-Jewish 185delAG*BRCA1 mutation carriers and their relatives were genotyped using 15 microsatellite markers and three SNPs spanning 12.5 MB, encompassing the BRCA1 gene locus. Estimation of mutation age was based on a subset of 11 markers spanning a region of ∼5 MB, using a previously developed algorithm applying the maximum likelihood method. Overall, 188 participants (154 carriers and 34 noncarriers) from 115 families were included: Ashkenazi, Iraq, Kuchin-Indians, Syria, Turkey, Iran, Tunisia, Bulgaria, non-Jewish English, non-Jewish Malaysian, and Hispanics. Haplotype analysis indicated that the 185delAG mutation arose 750–1500 years ago. In Ashkenazim, it is a founder mutation that arose 61 generations ago, and with a small group of founder mutations was introduced into the Hispanic population (conversos) ∼650 years ago, and into the Iraqi–Jewish community ∼450 years ago. The 185delAG mutation in the non-Jewish populations in Malaysia and the UK arose at least twice independently. We conclude that the 185delAG* BRCA1 mutation resides on a common haplotype among Ashkenazi Jews, and arose about 61 generations ago and arose independently at least twice in non-Jews. PMID:22763381

  3. Haplotype analysis of the 185delAG BRCA1 mutation in ethnically diverse populations.

    PubMed

    Laitman, Yael; Feng, Bing-Jian; Zamir, Itay M; Weitzel, Jeffrey N; Duncan, Paul; Port, Danielle; Thirthagiri, Eswary; Teo, Soo-Hwang; Evans, Gareth; Latif, Ayse; Newman, William G; Gershoni-Baruch, Ruth; Zidan, Jamal; Shimon-Paluch, Shani; Goldgar, David; Friedman, Eitan

    2013-02-01

    The 185delAG* BRCA1 mutation is encountered primarily in Jewish Ashkenazi and Iraqi individuals, and sporadically in non-Jews. Previous studies estimated that this is a founder mutation in Jewish mutation carriers that arose before the dispersion of Jews in the Diaspora ~2500 years ago. The aim of this study was to assess the haplotype in ethnically diverse 185delAG* BRCA1 mutation carriers, and to estimate the age at which the mutation arose. Ethnically diverse Jewish and non-Jewish 185delAG*BRCA1 mutation carriers and their relatives were genotyped using 15 microsatellite markers and three SNPs spanning 12.5 MB, encompassing the BRCA1 gene locus. Estimation of mutation age was based on a subset of 11 markers spanning a region of ~5 MB, using a previously developed algorithm applying the maximum likelihood method. Overall, 188 participants (154 carriers and 34 noncarriers) from 115 families were included: Ashkenazi, Iraq, Kuchin-Indians, Syria, Turkey, Iran, Tunisia, Bulgaria, non-Jewish English, non-Jewish Malaysian, and Hispanics. Haplotype analysis indicated that the 185delAG mutation arose 750-1500 years ago. In Ashkenazim, it is a founder mutation that arose 61 generations ago, and with a small group of founder mutations was introduced into the Hispanic population (conversos) ~650 years ago, and into the Iraqi-Jewish community ~450 years ago. The 185delAG mutation in the non-Jewish populations in Malaysia and the UK arose at least twice independently. We conclude that the 185delAG* BRCA1 mutation resides on a common haplotype among Ashkenazi Jews, and arose about 61 generations ago and arose independently at least twice in non-Jews. PMID:22763381

  4. A radiation hybrid map of the BRCA1 region of chromosome 17q12-q21

    SciTech Connect

    Abel, K.J.; Boehnke, M.; Prahalad, M.; Flejter, W.L.; Watkins, M.; Chandrasekharappa, S.C.; Glover, T.W. Howard Hughes Medical Institute, Ann Arbor, MI ); Ho, P.; VanderStoep, J.; Weber, B.L. ); Collins, F.S. Michigan Human Genome Center, Ann Arbor, MI Howard Hughes Medical Institute, Ann Arbor, MI )

    1993-09-01

    The chromosomal region 17q12-q21 contains a gene (BRCA1) conferring susceptibility to early-onset familial breast and ovarian cancer. An 8000-rad radiation-reduced hybrid (RH) panel was constructed to provide a resource for long-range mapping of this region. A large fraction of the hybrids ([approximately]90%) retained detectable human chromosome 17 sequences. The complete panel of 76 hybrids was scored for the presence or absence of 22 markers from this chromosomal region, including 14 cloned genes, seven microsatellite repeats, and one anonymous DNA segment. Statistical analysis of the marker retention data employing multipoint methods provided both comprehensive and framework maps of this chromosomal region, including distance estimates between adjacent markers. The comprehensive RH map includes 17 loci and spans 179 cRays[sub (8000)]. Likelihood ratios of at least 1000:1 support the 10-locus framework order: cen-D17S250-ERBB2-(THRA1, TOP2A)-D17S855-PPY-D17S190-MTBT1-GP3A-BTR-D17S588-tel. The order obtained from RH mapping, when used in conjunction with other methods, will be useful in linkage analysis of breast cancer families and will facilitate the development of a physical map of this region. 42 refs., 3 figs., 2 tabs.

  5. BRCA1-deficient mammary tumor cells are dependent on EZH2 expression and sensitive to Polycomb Repressive Complex 2-inhibitor 3-deazaneplanocin A

    PubMed Central

    Puppe, Julian; Drost, Rinske; Liu, Xiaoling; Joosse, Simon A; Evers, Bastiaan; Cornelissen-Steijger, Paulien; Nederlof, Petra; Yu, Qiang; Jonkers, Jos; van Lohuizen, Maarten; Pietersen, Alexandra M

    2009-01-01

    Introduction Treatment of breast cancer is becoming more individualized with the recognition of tumor subgroups that respond differently to available therapies. Breast cancer 1 gene (BRCA1)-deficient tumors are usually of the basal subtype and associated with poor survival rates, highlighting the need for more effective therapy. Methods We investigated a mouse model that closely mimics breast cancer arising in BRCA1-mutation carriers to better understand the molecular mechanism of tumor progression and tested whether targeting of the Polycomb-group protein EZH2 would be a putative therapy for BRCA1-deficient tumors. Results Gene expression analysis demonstrated that EZH2 is overexpressed in BRCA1-deficient mouse mammary tumors. By immunohistochemistry we show that an increase in EZH2 protein levels is also evident in tumors from BRCA1-mutation carriers. EZH2 is responsible for repression of genes driving differentiation and could thus be involved in the undifferentiated phenotype of these tumors. Importantly, we show that BRCA1-deficient cancer cells are selectively dependent on their elevated EZH2 levels. In addition, a chemical inhibitor of EZH2, 3-deazaneplanocin A (DZNep), is about 20-fold more effective in killing BRCA1-deficient cells compared to BRCA1-proficient mammary tumor cells. Conclusions We demonstrate by specific knock-down experiments that EZH2 overexpression is functionally relevant in BRCA1-deficient breast cancer cells. The effectiveness of a small molecule inhibitor indicates that EZH2 is a druggable target. The overexpression of EZH2 in all basal-like breast cancers warrants further investigation of the potential for targeting the genetic make-up of this particular breast cancer type. PMID:19709408

  6. Bias Correction Methods Explain Much of the Variation Seen in Breast Cancer Risks of BRCA1/2 Mutation Carriers

    PubMed Central

    Vos, Janet R.; Hsu, Li; Brohet, Richard M.; Mourits, Marian J.E.; de Vries, Jakob; Malone, Kathleen E.; Oosterwijk, Jan C.; de Bock, Geertruida H.

    2015-01-01

    Purpose Recommendations for treating patients who carry a BRCA1/2 gene are mainly based on cumulative lifetime risks (CLTRs) of breast cancer determined from retrospective cohorts. These risks vary widely (27% to 88%), and it is important to understand why. We analyzed the effects of methods of risk estimation and bias correction and of population factors on CLTRs in this retrospective clinical cohort of BRCA1/2 carriers. Patients and Methods The following methods to estimate the breast cancer risk of BRCA1/2 carriers were identified from the literature: Kaplan-Meier, frailty, and modified segregation analyses with bias correction consisting of including or excluding index patients combined with including or excluding first-degree relatives (FDRs) or different conditional likelihoods. These were applied to clinical data of BRCA1/2 families derived from our family cancer clinic for whom a simulation was also performed to evaluate the methods. CLTRs and 95% CIs were estimated and compared with the reference CLTRs. Results CLTRs ranged from 35% to 83% for BRCA1 and 41% to 86% for BRCA2 carriers at age 70 years width of 95% CIs: 10% to 35% and 13% to 46%, respectively). Relative bias varied from −38% to +16%. Bias correction with inclusion of index patients and untested FDRs gave the smallest bias: +2% (SD, 2%) in BRCA1 and +0.9% (SD, 3.6%) in BRCA2. Conclusion Much of the variation in breast cancer CLTRs in retrospective clinical BRCA1/2 cohorts is due to the bias-correction method, whereas a smaller part is due to population differences. Kaplan-Meier analyses with bias correction that includes index patients and a proportion of untested FDRs provide suitable CLTRs for carriers counseled in the clinic. PMID:26150446

  7. Human DNA repair genes.

    PubMed

    Wood, R D; Mitchell, M; Sgouros, J; Lindahl, T

    2001-02-16

    Cellular DNA is subjected to continual attack, both by reactive species inside cells and by environmental agents. Toxic and mutagenic consequences are minimized by distinct pathways of repair, and 130 known human DNA repair genes are described here. Notable features presently include four enzymes that can remove uracil from DNA, seven recombination genes related to RAD51, and many recently discovered DNA polymerases that bypass damage, but only one system to remove the main DNA lesions induced by ultraviolet light. More human DNA repair genes will be found by comparison with model organisms and as common folds in three-dimensional protein structures are determined. Modulation of DNA repair should lead to clinical applications including improvement of radiotherapy and treatment with anticancer drugs and an advanced understanding of the cellular aging process. PMID:11181991

  8. Mutation analysis of BRCA1 and BRCA2 in a male breast cancer population

    SciTech Connect

    Friedman, L.S.; Gayther, S.A.; Ponder, B.A.J.

    1997-02-01

    A population-based series of 54 male breast cancer cases from Southern California were analyzed for germ-line mutations in the inherited breast/ovarian cancer genes, BRCA1 and BRCA2. Nine (17%) of the patients had a family history of breast and/or ovarian cancer in at least one first-degree relative. A further seven (13%) of the patients reported breast/ovarian cancer in at least one second-degree relative and in no first-degree relatives. No germ-line BRCA1 mutations were found. Two male breast cancer patients (4% of the total) were found to carry novel truncating mutations in the BRCA2 gene. Only one of the two male breast cancer patients carrying a BRCA2 mutation had a family history of cancer, with one case of ovarian cancer in a first-degree relative. The remaining eight cases (89%) of male breast cancer with a family history of breast/ovarian cancer in first-degree relatives remain unaccounted for by mutations in either the BRCA1 gene or the BRCA2 gene. 23 refs., 1 fig., 5 tabs.

  9. The Novel Ribonucleotide Reductase Inhibitor COH29 Inhibits DNA Repair In Vitro

    PubMed Central

    Chen, Mei-Chuan; Zhou, Bingsen; Zhang, Keqiang; Yuan, Yate-Ching; Un, Frank; Hu, Shuya; Chou, Chih-Ming; Chen, Chun-Han; Wu, Jun; Wang, Yan; Liu, Xiyong; Smith, D. Lynne; Li, Hongzhi; Liu, Zheng; Warden, Charles D.; Su, Leila; Malkas, Linda H.; Chung, Young Min; Hu, Mickey C.-T.

    2015-01-01

    COH29 [N-(4-(3,4-dihydroxyphenyl)-5-phenylthiazol-2-yl)-3,4-dihydroxybenzamide], a novel antimetabolite drug developed at City of Hope Cancer Center, has anticancer activity that stems primarily from the inhibition of human ribonucleotide reductase (RNR). This key enzyme in deoxyribonucleotide biosynthesis is the target of established clinical agents such as hydroxyurea and gemcitabine because of its critical role in DNA replication and repair. Herein we report that BRCA-1–defective human breast cancer cells are more sensitive than wild-type BRCA-1 counterparts to COH29 in vitro and in vivo. Microarray gene expression profiling showed that COH29 reduces the expression of DNA repair pathway genes, suggesting that COH29 interferes with these pathways. It is well established that BRCA1 plays a role in DNA damage repair, especially homologous recombination (HR) repair, to maintain genome integrity. In BRCA1-defective HCC1937 breast cancer cells, COH29 induced more double-strand breaks (DSBs) and DNA-damage response than in HCC1937 + BRCA1 cells. By EJ5– and DR–green fluorescent protein (GFP) reporter assay, we found that COH29 could inhibit nonhomologous end joining (NHEJ) efficiency and that no HR activity was detected in HCC1937 cells, suggesting that repression of the NHEJ repair pathway may be involved in COH29-induced DSBs in BRCA1-deficient HCC1937 cells. Furthermore, we observed an accumulation of nuclear Rad51 foci in COH29-treated HCC1937 + BRCA1 cells, suggesting that BRCA1 plays a crucial role in repairing and recovering drug-induced DNA damage by recruiting Rad51 to damage sites. In summary, we describe here additional biologic effects of the RNR inhibitor COH29 that potentially strengthen its use as an anticancer agent. PMID:25814515

  10. The Novel Ribonucleotide Reductase Inhibitor COH29 Inhibits DNA Repair In Vitro.

    PubMed

    Chen, Mei-Chuan; Zhou, Bingsen; Zhang, Keqiang; Yuan, Yate-Ching; Un, Frank; Hu, Shuya; Chou, Chih-Ming; Chen, Chun-Han; Wu, Jun; Wang, Yan; Liu, Xiyong; Smith, D Lynne; Li, Hongzhi; Liu, Zheng; Warden, Charles D; Su, Leila; Malkas, Linda H; Chung, Young Min; Hu, Mickey C-T; Yen, Yun

    2015-06-01

    COH29 [N-(4-(3,4-dihydroxyphenyl)-5-phenylthiazol-2-yl)-3,4-dihydroxybenzamide], a novel antimetabolite drug developed at City of Hope Cancer Center, has anticancer activity that stems primarily from the inhibition of human ribonucleotide reductase (RNR). This key enzyme in deoxyribonucleotide biosynthesis is the target of established clinical agents such as hydroxyurea and gemcitabine because of its critical role in DNA replication and repair. Herein we report that BRCA-1-defective human breast cancer cells are more sensitive than wild-type BRCA-1 counterparts to COH29 in vitro and in vivo. Microarray gene expression profiling showed that COH29 reduces the expression of DNA repair pathway genes, suggesting that COH29 interferes with these pathways. It is well established that BRCA1 plays a role in DNA damage repair, especially homologous recombination (HR) repair, to maintain genome integrity. In BRCA1-defective HCC1937 breast cancer cells, COH29 induced more double-strand breaks (DSBs) and DNA-damage response than in HCC1937 + BRCA1 cells. By EJ5- and DR-green fluorescent protein (GFP) reporter assay, we found that COH29 could inhibit nonhomologous end joining (NHEJ) efficiency and that no HR activity was detected in HCC1937 cells, suggesting that repression of the NHEJ repair pathway may be involved in COH29-induced DSBs in BRCA1-deficient HCC1937 cells. Furthermore, we observed an accumulation of nuclear Rad51 foci in COH29-treated HCC1937 + BRCA1 cells, suggesting that BRCA1 plays a crucial role in repairing and recovering drug-induced DNA damage by recruiting Rad51 to damage sites. In summary, we describe here additional biologic effects of the RNR inhibitor COH29 that potentially strengthen its use as an anticancer agent. PMID:25814515

  11. Progesterone Receptor A Stability Is Mediated by Glycogen Synthase Kinase-3β in the Brca1-deficient Mammary Gland*

    PubMed Central

    Wang, Shaohui; Li, Ying; Hsu, Pang-Hung; Lee, Sou-Ying; Kim, Yoon; Lee, Eva Y.-H. P.

    2013-01-01

    Germ line mutations of the BRCA1 gene increase the risk of breast and ovarian cancer, but the basis of this tissue-specific tumor predisposition is not fully understood. Previously, we reported that the progesterone receptors are stabilized in Brca1-deficient mammary epithelial cells, and treating with anti-progesterone delays mammary tumorigenesis in Brca1/p53 conditional knock-out mice, suggesting that the progesterone has a critical role in breast carcinogenesis. To further explore how the stability of progesterone receptor is modulated, here, we have found that glycogen synthase kinase (GSK)-3β phosphorylation of progesterone receptor-A (PR-A) facilitates its ubiquitination. GSK-3β-mediated phosphorylation of serine 390 in PR-A regulates its subsequent ubiquitination and protein stability. Expression of PR-AS390A mutant in the human breast epithelial cells, MCF-10A, results in enhanced proliferation and formation of aberrant acini structure in the three-dimensional culture. Consistently, reduction of phosphorylation of serine 390 of PR-A and GSK-3β activity is observed in the Brca1-deficient mammary gland. Taken together, these results provide important aspects of tissue specificity of BRCA1-mediated suppression of breast carcinogenesis. PMID:23880761

  12. Development and Validation of a Next-Generation Sequencing Assay for BRCA1 and BRCA2 Variants for the Clinical Laboratory.

    PubMed

    Strom, Charles M; Rivera, Steven; Elzinga, Christopher; Angeloni, Taraneh; Rosenthal, Sun Hee; Goos-Root, Dana; Siaw, Martin; Platt, Jamie; Braastadt, Cory; Cheng, Linda; Ross, David; Sun, Weimin

    2015-01-01

    The objective of this study was to design and validate a next-generation sequencing assay (NGS) to detect BRCA1 and BRCA2 mutations. We developed an assay using random shearing of genomic DNA followed by RNA bait tile hybridization and NGS sequencing on both the Illumina MiSeq and Ion Personal Gene Machine (PGM). We determined that the MiSeq Reporter software supplied with the instrument could not detect deletions greater than 9 base pairs. Therefore, we developed an alternative alignment and variant calling software, Quest Sequencing Analysis Pipeline (QSAP), that was capable of detecting large deletions and insertions. In validation studies, we used DNA from 27 stem cell lines, all with known deleterious BRCA1 or BRCA2 mutations, and DNA from 67 consented control individuals who had a total of 352 benign variants. Both the MiSeq/QSAP combination and PGM/Torrent Suite combination had 100% sensitivity for the 379 known variants in the validation series. However, the PGM/Torrent Suite combination had a lower intra- and inter-assay precision of 96.2% and 96.7%, respectively when compared to the MiSeq/QSAP combination of 100% and 99.4%, respectively. All PGM/Torrent Suite inconsistencies were false-positive variant assignments. We began commercial testing using both platforms and in the first 521 clinical samples MiSeq/QSAP had 100% sensitivity for BRCA1/2 variants, including a 64-bp deletion and a 10-bp insertion not identified by PGM/Torrent Suite, which also suffered from a high false-positive rate. Neither the MiSeq nor PGM platform with their supplied alignment and variant calling software are appropriate for a clinical laboratory BRCA sequencing test. We have developed an NGS BRCA1/2 sequencing assay, MiSeq/QSAP, with 100% analytic sensitivity and specificity in the validation set consisting of 379 variants. The MiSeq/QSAP combination has sufficient performance for use in a clinical laboratory. PMID:26295337

  13. Development and Validation of a Next-Generation Sequencing Assay for BRCA1 and BRCA2 Variants for the Clinical Laboratory

    PubMed Central

    Strom, Charles M.; Rivera, Steven; Elzinga, Christopher; Angeloni, Taraneh; Rosenthal, Sun Hee; Goos-Root, Dana; Siaw, Martin; Platt, Jamie; Braastadt, Cory; Cheng, Linda; Ross, David; Sun, Weimin

    2015-01-01

    The objective of this study was to design and validate a next-generation sequencing assay (NGS) to detect BRCA1 and BRCA2 mutations. We developed an assay using random shearing of genomic DNA followed by RNA bait tile hybridization and NGS sequencing on both the Illumina MiSeq and Ion Personal Gene Machine (PGM). We determined that the MiSeq Reporter software supplied with the instrument could not detect deletions greater than 9 base pairs. Therefore, we developed an alternative alignment and variant calling software, Quest Sequencing Analysis Pipeline (QSAP), that was capable of detecting large deletions and insertions. In validation studies, we used DNA from 27 stem cell lines, all with known deleterious BRCA1 or BRCA2 mutations, and DNA from 67 consented control individuals who had a total of 352 benign variants. Both the MiSeq/QSAP combination and PGM/Torrent Suite combination had 100% sensitivity for the 379 known variants in the validation series. However, the PGM/Torrent Suite combination had a lower intra- and inter-assay precision of 96.2% and 96.7%, respectively when compared to the MiSeq/QSAP combination of 100% and 99.4%, respectively. All PGM/Torrent Suite inconsistencies were false-positive variant assignments. We began commercial testing using both platforms and in the first 521 clinical samples MiSeq/QSAP had 100% sensitivity for BRCA1/2 variants, including a 64-bp deletion and a 10-bp insertion not identified by PGM/Torrent Suite, which also suffered from a high false-positive rate. Neither the MiSeq nor PGM platform with their supplied alignment and variant calling software are appropriate for a clinical laboratory BRCA sequencing test. We have developed an NGS BRCA1/2 sequencing assay, MiSeq/QSAP, with 100% analytic sensitivity and specificity in the validation set consisting of 379 variants. The MiSeq/QSAP combination has sufficient performance for use in a clinical laboratory. PMID:26295337

  14. Chemotherapy for Patients with BRCA1 and BRCA2-Mutated Ovarian Cancer: Same or Different?

    PubMed

    Tan, David S P; Kaye, Stanley B

    2015-01-01

    Retrospective studies have shown an improved prognosis, higher response rates to platinum-containing regimens, and longer treatment-free intervals between relapses in patients with BRCA 1 and BRCA 2 (BRCA1/2)-mutated ovarian cancer (BMOC) compared with patients who are not carriers of this mutation. These features of BMOC are attributed to homologous-recombination repair (HR) deficiency in the absence of BRCA1/2 function, which results in an impaired ability of tumor cells to repair platinum-induced double-strand breaks (DSBs), thereby conferring increased chemosensitivity and increased sensitivity to poly(ADP-ribose) polymerase (PARP) enzyme inhibition and other DNA-damaging chemotherapeutic agents such as pegylated liposomal doxorubicin (PLD). Therefore, the chemotherapeutic approach for patients with BMOC should focus on treatment with platinum-based chemotherapy at first-line and recurrent-disease settings and measures to increase the platinum-free interval following early platinum-resistant relapse (i.e., progression-free survival of less than 6 months from last platinum-based chemotherapy) by using nonplatinum cytotoxic agents, with the aim of reintroducing platinum again at a later date. The role of first-line intraperitoneal platinum-based therapy in the specific context of BMOC also merits further analysis. Other than platinum, alternative DNA-damaging agents (including PLD and trabectedin) also may have a therapeutic role in patients with recurrent BMOC. The recent approval of olaparib for clinical use in Europe and the United States will also affect chemotherapeutic strategies for these patients. Further work to clarify the precise relationship between BRCA1/2 mutation genotype and clinical phenotype is crucial to delineating the optimal therapeutic choices in the future for patients with BMOC. PMID:25993149

  15. Depletion of eIF2·GTP·Met-tRNAi translation initiation complex up-regulates BRCA1 expression in vitro and in vivo.

    PubMed

    Aktas, Bertal H; Bordelois, Paula; Peker, Selen; Merajver, Sophia; Halperin, Jose A

    2015-03-30

    Most sporadic breast and ovarian cancers express low levels of the breast cancer susceptibility gene, BRCA1. The BRCA1 gene produces two transcripts, mRNAa and mRNAb. mRNAb, present in breast cancer but not in normal mammary epithelial cells, contains three upstream open reading frames (uORFs) in its 5'UTR and is translationally repressed. Comparable tandem uORFs are characteristically seen in mRNAs whose translational efficiency paradoxically increases when the overall translation rate is decreased due to phosphorylation of eukaryotic translation initiation factor 2 α (eIF2α). Here we show fish oil derived eicosopanthenoic acid (EPA) that induces eIF2α phosphorylation translationally up-regulates the expression of BRCA1 in human breast cancer cells. We demonstrate further that a diet rich in EPA strongly induces expression of BRCA1 in human breast cancer xenografts. PMID:25762631

  16. Sanger Sequencing for BRCA1 c.68_69del, BRCA1 c.5266dup and BRCA2 c.5946del Mutation Screen on Pap Smear Cytology Samples

    PubMed Central

    Lee, Sin Hang; Zhou, Shaoxia; Zhou, Tianjun; Hong, Guofan

    2016-01-01

    Three sets of polymerase chain reaction (PCR) primers were designed for heminested PCR amplification of the target DNA fragments in the human genome which include the site of BRCA1 c.68_69del, BRCA1 c.5266dup and BRCA2 c.5946del respectively, to prepare the templates for direct Sanger sequencing screen of these three founder mutations. With a robust PCR mixture, crude proteinase K digestate of the fixed cervicovaginal cells in the liquid-based Papanicolaou (Pap) cytology specimens can be used as the sample for target DNA amplification without pre-PCR DNA extraction, purification and quantitation. The post-PCR products can be used directly as the sequencing templates without further purification or quantitation. By simplifying the frontend procedures for template preparation, the cost for screening these three founder mutations can be reduced to about US $200 per test when performed in conjunction with human papillomavirus (HPV) assays now routinely ordered for cervical cancer prevention. With this projected price structure, selective patients in a high-risk population can be tested and each provided with a set of DNA sequencing electropherograms to document the absence or presence of these founder mutations in her genome to help assess inherited susceptibility to breast and ovarian cancer in this era of precision molecular personalized medicine. PMID:26867194

  17. Sanger Sequencing for BRCA1 c.68_69del, BRCA1 c.5266dup and BRCA2 c.5946del Mutation Screen on Pap Smear Cytology Samples.

    PubMed

    Lee, Sin Hang; Zhou, Shaoxia; Zhou, Tianjun; Hong, Guofan

    2016-01-01

    Three sets of polymerase chain reaction (PCR) primers were designed for heminested PCR amplification of the target DNA fragments in the human genome which include the site of BRCA1 c.68_69del, BRCA1 c.5266dup and BRCA2 c.5946del respectively, to prepare the templates for direct Sanger sequencing screen of these three founder mutations. With a robust PCR mixture, crude proteinase K digestate of the fixed cervicovaginal cells in the liquid-based Papanicolaou (Pap) cytology specimens can be used as the sample for target DNA amplification without pre-PCR DNA extraction, purification and quantitation. The post-PCR products can be used directly as the sequencing templates without further purification or quantitation. By simplifying the frontend procedures for template preparation, the cost for screening these three founder mutations can be reduced to about US $200 per test when performed in conjunction with human papillomavirus (HPV) assays now routinely ordered for cervical cancer prevention. With this projected price structure, selective patients in a high-risk population can be tested and each provided with a set of DNA sequencing electropherograms to document the absence or presence of these founder mutations in her genome to help assess inherited susceptibility to breast and ovarian cancer in this era of precision molecular personalized medicine. PMID:26867194

  18. BRCA1 and BRCA2 Mutations

    MedlinePlus

    ... testing may be offered. Genetic testing requires a DNA sample from blood or saliva. There are several ... specific BRCA mutation is present. This is called DNA sequencing. Your DNA then can be tested to ...

  19. Spectrum of BRCA1/2 point mutations and genomic rearrangements in high-risk breast/ovarian cancer Chilean families.

    PubMed

    Gonzalez-Hormazabal, Patricio; Gutierrez-Enriquez, Sara; Gaete, Daniel; Reyes, Jose M; Peralta, Octavio; Waugh, Enrique; Gomez, Fernando; Margarit, Sonia; Bravo, Teresa; Blanco, Rafael; Diez, Orland; Jara, Lilian

    2011-04-01

    The distribution of BRCA1/2 germline mutations in breast/ovarian cancer (BC/OC) families varies among different populations. In the Chilean population, there are only two reports of mutation analysis of BRCA1/2, and these included a low number of BC and/or OC patients. Moreover, the prevalence of BRCA1/2 genomic rearrangements in Chilean and in other South American populations is unknown. In this article, we present the mutation-detection data corresponding to a set of 326 high-risk families analyzed by conformation-sensitive gel electrophoresis and heteroduplex analysis. To determine the contribution of BRCA1/2 LGRs in Chilean BC patients, we analyzed 56 high-risk subjects with no pathogenic BRCA1/2 point mutations. Germline BRCA1/2 point mutations were found in 23 (7.1%) of the 326 Chilean families. Families which had at least three BC and/or OC cases showed the highest frequency of mutations (15.9%). We identified 14 point pathogenic mutations. Three recurrent mutations in BRCA1 (c.187_188delAG, c.2605_2606delTT, and c.3450_3453delCAAG) and three in BRCA2 (c.4969_4970insTG, c.5374_5377delTATG, and c.6503_6504delTT) contributed to 63.6 and 66.7% of all the deleterious mutations of each gene, which may reflect the presence of region-specific founder effects. Taken together BRCA1/2 recurrent point mutations account for 65.2% (15/23) of the BRCA1/2 (+) families. No large deletions or duplications involving BRCA1/2 were identified in a subgroup of 56 index cases negative for BRCA1/2 point mutations. Our study, which is the largest conducted to date in a South American population, provides a comprehensive analysis on the type and distribution of BRCA1/2 mutations and allelic variants. PMID:20859677

  20. Synchronous ovarian dysgerminoma and breast carcinoma in a patient with positive immunostain of BRCA1.

    PubMed

    Băltătescu, G I; Așchie, M; Sârbu, V

    2013-01-01

    Breast cancer is the most common malignant neoplastic process and the second cause of death for women. Ovarian cancer, despite having a lower incidence, represents an important cause of morbidity and mortality because it is usually discovered in advanced stages. The presence of both forms of cancer in a patient is associated with a high risk of BRCA1 gene mutations, which are responsible, together with BRCA2 gene mutations, for most of the breast and ovarian cancer family. Our case is special because it presents a synchronous and a rare association of a primary ovarian dysgerminoma (with an incidence of less than 1% of ovarian cancers) and a primary breast carcinoma in a patient of 46 years old. Immunohistochemical examination was performed using a panel of five biomarkers: oestrogen receptor, progesterone receptor, Herceptest, p53 and BRCA1. In our case, we identified a negative hormonal status and the absence of HER2/neu expression but a positive immuno-expression for p53 protein and BRCA1 protein. Postoperative course was favourable for the patient after each surgery, and she was discharged with the recommendation to perform a genetic counselling. PMID:23618579

  1. Alcohol consumption and the risk of breast cancer among BRCA1 and BRCA2 mutation carriers.

    PubMed

    Dennis, Jessica; Ghadirian, Parviz; Little, Julian; Lubinski, Jan; Gronwald, Jacek; Kim-Sing, Charmaine; Foulkes, William; Moller, Pal; Lynch, Henry T; Neuhausen, Susan L; Domchek, Susan; Armel, Susan; Isaacs, Claudine; Tung, Nadine; Sweet, Kevin; Ainsworth, Peter; Sun, Ping; Krewski, Daniel; Narod, Steven

    2010-12-01

    Alcohol consumption increases the risk of breast cancer among women in the general population, but its effect on women who carry a BRCA gene mutation is unclear. We conducted a case-control study of 1925 matched pairs of predominantly premenopausal women who carry a BRCA1 or a BRCA2 mutation. Information on current alcohol consumption was obtained from a questionnaire administered during the course of genetic counselling or at the time of enrollment. A modest inverse association between breast cancer and reported current alcohol consumption was observed among women with a BRCA1 mutation (OR = 0.82, 95% CI 0.70-0.96), but not among women with a BRCA2 mutation (OR = 1.00; 95% CI 0.71-1.41). Compared to non-drinkers, exclusive consumption of wine was associated with a significant reduction in the risk of breast cancer among BRCA1 carriers (p-trend = 0.01). Alcohol consumption does not appear to increase breast cancer risk in women carrying a BRCA gene mutation. PMID:20541936

  2. BRCA1 and BRCA2 Mutations in Ethnic Lebanese Arab Women With High Hereditary Risk Breast Cancer

    PubMed Central

    Zgheib, Nathalie K.; Assi, Hussein A.; Khoury, Katia E.; Bidet, Yannick; Jaber, Sara M.; Charara, Raghid N.; Farhat, Rania A.; Kreidieh, Firas Y.; Decousus, Stephanie; Romero, Pierre; Nemer, Georges M.; Salem, Ziad; Shamseddine, Ali; Tfayli, Arafat; Abbas, Jaber; Jamali, Faek; Seoud, Muhieddine; Armstrong, Deborah K.; Bignon, Yves-Jean; Uhrhammer, Nancy

    2015-01-01

    Purpose. Breast cancer is the most common malignancy among women in Lebanon and in Arab countries, with 50% of cases presenting before the age of 50 years. Methods. Between 2009 and 2012, 250 Lebanese women with breast cancer who were considered to be at high risk of carrying BRCA1 or BRCA2 mutations because of presentation at young age and/or positive family history (FH) of breast or ovarian cancer were recruited. Clinical data were analyzed statistically. Coding exons and intron-exon boundaries of BRCA1 and BRCA2 were sequenced from peripheral blood DNA. All patients were tested for BRCA1 rearrangements using multiplex ligation-dependent probe amplification (MLPA). BRCA2 MLPA was done in selected cases. Results. Overall, 14 of 250 patients (5.6%) carried a deleterious BRCA mutation (7 BRCA1, 7 BRCA2) and 31 (12.4%) carried a variant of uncertain significance. Eight of 74 patients (10.8%) aged ≤40 years with positive FH and only 1 of 74 patients (1.4%) aged ≤40 years without FH had a mutated BRCA. Four of 75 patients (5.3%) aged 41–50 years with FH had a deleterious mutation. Only 1 of 27 patients aged >50 years at diagnosis had a BRCA mutation. All seven patients with BRCA1 mutations had grade 3 infiltrating ductal carcinoma and triple-negative breast cancer. Nine BRCA1 and 17 BRCA2 common haplotypes were observed. Conclusion. Prevalence of deleterious BRCA mutations is lower than expected and does not support the hypothesis that BRCA mutations alone cause the observed high percentage of breast cancer in young women of Lebanese and Arab descent. Studies to search for other genetic mutations are recommended. PMID:25777348

  3. Peptide library approach to uncover phosphomimetic inhibitors of the BRCA1 C-terminal domain.

    PubMed

    White, E Railey; Sun, Luxin; Ma, Zhong; Beckta, Jason M; Danzig, Brittany A; Hacker, David E; Huie, Melissa; Williams, David C; Edwards, Ross A; Valerie, Kristoffer; Glover, J N Mark; Hartman, Matthew C T

    2015-05-15

    Many intracellular protein-protein interactions are mediated by the phosphorylation of serine, and phosphoserine-containing peptides can inhibit these interactions. However, hydrolysis of the phosphate by phosphatases, and the poor cell permeability associated with phosphorylated peptides has limited their utility in cellular and in vivo contexts. Compounding the problem, strategies to replace phosphoserine in peptide inhibitors with easily accessible mimetics (such as Glu or Asp) routinely fail. Here, we present an in vitro selection strategy for replacement of phosphoserine. Using mRNA display, we created a 10 trillion member structurally diverse unnatural peptide library. From this library, we found a peptide that specifically binds to the C-terminal domain (BRCT)2 of breast cancer associated protein 1 (BRCA1) with an affinity comparable to phosphorylated peptides. A crystal structure of the peptide bound reveals that the pSer-x-x-Phe motif normally found in BRCA1 (BRCT)2 binding partners is replaced by a Glu-x-x-4-fluoroPhe and that the peptide picks up additional contacts on the protein surface not observed in cognate phosphopeptide binding. Expression of the peptide in human cells led to defects in DNA repair by homologous recombination, a process BRCA1 is known to coordinate. Overall, this work validates a new in vitro selection approach for the development of inhibitors of protein-protein interactions mediated by serine phosphorylation. PMID:25654734

  4. Peptide Library Approach to Uncover Phosphomimetic Inhibitors of the BRCA1 C-Terminal Domain

    PubMed Central

    White, E. Railey; Sun, Luxin; Ma, Zhong; Beckta, Jason M.; Danzig, Brittany A.; Hacker, David E.; Huie, Melissa; Williams, David C.; Edwards, Ross A.; Valerie, Kristoffer; Mark Glover, J. N.; Hartman, Matthew C. T.

    2015-01-01

    Many intracellular protein–protein interactions are mediated by the phosphorylation of serine, and phosphoserine-containing peptides can inhibit these interactions. However, hydrolysis of the phosphate by phosphatases, and the poor cell permeability associated with phosphorylated peptides has limited their utility in cellular and in vivo contexts. Compounding the problem, strategies to replace phosphoserine in peptide inhibitors with easily accessible mimetics (such as Glu or Asp) routinely fail. Here, we present an in vitro selection strategy for replacement of phosphoserine. Using mRNA display, we created a 10 trillion member structurally diverse unnatural peptide library. From this library, we found a peptide that specifically binds to the C-terminal domain (BRCT)2 of breast cancer associated protein 1 (BRCA1) with an affinity comparable to phosphorylated peptides. A crystal structure of the peptide bound reveals that the pSer-x-x-Phe motif normally found in BRCA1 (BRCT)2 binding partners is replaced by a Glu-x-x-4-fluoroPhe and that the peptide picks up additional contacts on the protein surface not observed in cognate phosphopeptide binding. Expression of the peptide in human cells led to defects in DNA repair by homologous recombination, a process BRCA1 is known to coordinate. Overall, this work validates a new in vitro selection approach for the development of inhibitors of protein–protein interactions mediated by serine phosphorylation. PMID:25654734

  5. BRCA1 and BRCA2 as molecular targets for phytochemicals indole-3-carbinol and genistein in breast and prostate cancer cells

    PubMed Central

    Fan, S; Meng, Q; Auborn, K; Carter, T; Rosen, E M

    2006-01-01

    Indole-3-carbinol (I3C) and genistein are naturally occurring chemicals derived from cruciferous vegetables and soy, respectively, with potential cancer prevention activity for hormone-responsive tumours (e.g., breast and prostate cancers). Previously, we showed that I3C induces BRCA1 expression and that both I3C and BRCA1 inhibit oestrogen (E2)-stimulated oestrogen receptor (ER-α) activity in human breast cancer cells. We now report that both I3C and genistein induce the expression of both breast cancer susceptibility genes (BRCA1 and BRCA2) in breast (MCF-7 and T47D) and prostate (DU-145 and LNCaP) cancer cell types, in a time- and dose-dependent fashion. Induction of the BRCA genes occurred at low doses of I3C (20 μM) and genistein (0.5–1.0 μM), suggesting potential relevance to cancer prevention. A combination of I3C and genistein gave greater than expected induction of BRCA expression. Studies using small interfering RNAs (siRNAs) and BRCA expression vectors suggest that the phytochemical induction of BRCA2 is due, in part, to BRCA1. Functional studies suggest that I3C-mediated cytoxicity is, in part, dependent upon BRCA1 and BRCA2. Inhibition of E2-stimulated ER-α activity by I3C and genistein was dependent upon BRCA1; and inhibition of ligand-inducible androgen receptor (AR) activity by I3C and genistein was partially reversed by BRCA1-siRNA. Finally, we provide evidence suggesting that the phytochemical induction of BRCA1 expression is due, in part, to endoplasmic reticulum stress response signalling. These findings suggest that the BRCA genes are molecular targets for some of the activities of I3C and genistein. PMID:16434996

  6. Removal of Ovaries and Fallopian Tubes Cuts Cancer Risk for BRCA1/2 Carriers | Division of Cancer Prevention

    Cancer.gov

    Surgery that removes the ovaries and fallopian tubes, called salpingo-oophorectomy, is one of the most effective ways to decrease a woman's risk of breast and gynecologic cancer if she carries aBRCA1 or BRCA2 gene mutation. However, the true degree of risk reduction has not been precisely defined. |

  7. Population-based screening for breast and ovarian cancer risk due to BRCA1 and BRCA2

    PubMed Central

    Gabai-Kapara, Efrat; Lahad, Amnon; Kaufman, Bella; Friedman, Eitan; Segev, Shlomo; Renbaum, Paul; Beeri, Rachel; Gal, Moran; Grinshpun-Cohen, Julia; Djemal, Karen; Mandell, Jessica B.; Lee, Ming K.; Beller, Uziel; Catane, Raphael; King, Mary-Claire; Levy-Lahad, Ephrat

    2014-01-01

    In the Ashkenazi Jewish (AJ) population of Israel, 11% of breast cancer and 40% of ovarian cancer are due to three inherited founder mutations in the cancer predisposition genes BRCA1 and BRCA2. For carriers of these mutations, risk-reducing salpingo-oophorectomy significantly reduces morbidity and mortality. Population screening for these mutations among AJ women may be justifiable if accurate estimates of cancer risk for mutation carriers can be obtained. We therefore undertook to determine risks of breast and ovarian cancer for BRCA1 and BRCA2 mutation carriers ascertained irrespective of personal or family history of cancer. Families harboring mutations in BRCA1 or BRCA2 were ascertained by identifying mutation carriers among healthy AJ males recruited from health screening centers and outpatient clinics. Female relatives of the carriers were then enrolled and genotyped. Among the female relatives with BRCA1 or BRCA2 mutations, cumulative risk of developing either breast or ovarian cancer by age 60 and 80, respectively, were 0.60 (± 0.07) and 0.83 (± 0.07) for BRCA1 carriers and 0.33 (± 0.09) and 0.76 (± 0.13) for BRCA2 carriers. Risks were higher in recent vs. earlier birth cohorts (P = 0.006). High cancer risks in BRCA1 or BRCA2 mutation carriers identified through healthy males provide an evidence base for initiating a general screening program in the AJ population. General screening would identify many carriers who are not evaluated by genetic testing based on family history criteria. Such a program could serve as a model to investigate implementation and outcomes of population screening for genetic predisposition to cancer in other populations. PMID:25192939

  8. miR-342 overexpression results in a synthetic lethal phenotype in BRCA1-mutant HCC1937 breast cancer cells

    PubMed Central

    Crippa, Elisabetta; Folini, Marco; Pennati, Marzia; Zaffaroni, Nadia; Pierotti, Marco A.; Gariboldi, Manuela

    2016-01-01

    Expression of miR-342 has been strongly correlated with estrogen receptor (ER) status in breast cancer, where it is highest in ER-positive and lowest in triple-negative tumors. We investigated the effects of miR-342 transfection in the triple-negative breast cancer cell lines MDA-MB-231 and HCC1937, the latter carrying a germ-line BRCA1 mutation. Reconstitution of miR-342 led to caspase-dependent induction of apoptosis only in HCC1937 cells, while overexpression of wild-type BRCA1 in HCC1937 cells counteracted miR-342-mediated induction of apoptosis, suggesting that miR-342 overexpression and the lack of functional BRCA1 result in a synthetic lethal phenotype. Moreover, siRNA-mediated depletion of BRCA1 in MDA-MB-231 cells expressing the wild-type protein led to apoptosis upon transfection with miR-342. Using an in silico approach and a luciferase reporter system, we identified and functionally validated the Baculoviral IAP repeat-containing 6 gene (BIRC6), which encodes the anti-apoptotic factor Apollon/BRUCE, as a target of miR-342. In our model, BIRC6 likely acts as a determinant of the miRNA-dependent induction of apoptosis in BRCA1-mutant HCC1937 cells. Together, our findings suggest a tumor-suppressive function of miR-342 that could be exploited in the treatment of a subset of BRCA1-mutant hereditary breast cancers. PMID:26919240

  9. Quality of Life and Psychological State in Chinese Breast Cancer Patients Who Received BRCA1/2 Genetic Testing

    PubMed Central

    Qiu, Jiajia; Guan, Jiaqin; Yang, Xiaochen; Wu, Jiong; Liu, Guangyu; Di, Genhong; Chen, Canming; Hou, Yifeng; Han, Qixia; Shen, Zhenzhou; Shao, Zhimin; Hu, Zhen

    2016-01-01

    Background This study aims to understand the quality of life (QOL) and psychological state (PS) of Chinese breast cancer patients who received BRCA1/2 genetic testing; to examine the psychological changes between BRCA1/2 mutation carriers and non-carriers; and to further explore the psychological experience of BRCA1/2 mutation carriers. Methods This study was combined with quantitative and qualitative designs. First, we performed a quantitative investigation using FACT-B (Chinese version) and Irritability, Depression and Anxiety scale (IDA) to assess the QOL and PS in breast cancer patients who received BRCA1/2 genetic testing. Then semi-structured in-depth qualitative interviews among 13 mutation carriers were conducted in hospital. Results Results from the quantitative study showed QOL scores were relatively high and the IDA scores were relatively low among the patients, and there was no significant difference in the QOL or IDA scores between non-carriers and carriers. Based on the qualitative analysis, four main themes emerged: (1) Finding the reason for having breast cancer; (2) Negative emotions; (3) Behavioral changes; (4) Lack of information. Conclusions The present study showed that QOL and PS are good among the breast cancer patients who received genetic testing. Genetic testing itself does not cause long psychosocial effects. BRCA1/2 mutation carriers may have certain negative emotions at the first stage they knew the testing results and may initiate behavioral and lifestyle changes. The patients with a BRCA1/2 mutation desire knowledge with regard to genetic aspects in mainland China. Professional information and advice can be provided to relieve the patients’ negative emotions when they were informed of gene defect. PMID:27428375

  10. Brca1 is required for embryonic development of the mouse cerebral cortex to normal size by preventing apoptosis of early neural progenitors.

    PubMed

    Pulvers, Jeremy N; Huttner, Wieland B

    2009-06-01

    The extent of apoptosis of neural progenitors is known to influence the size of the cerebral cortex. Mouse embryos lacking Brca1, the ortholog of the human breast cancer susceptibility gene BRCA1, show apoptosis in the neural tube, but the consequences of this for brain development have not been studied. Here we investigated the role of Brca1 during mouse embryonic cortical development by deleting floxed Brca1 using Emx1-Cre, which leads to conditional gene ablation specifically in the dorsal telencephalon after embryonic day (E) 9.5. The postnatal Brca1-ablated cerebral cortex was substantially reduced in size with regard to both cortical thickness and surface area. Remarkably, although the thickness of the cortical layers (except for the upper-most layer) was decreased, cortical layering as such was essentially unperturbed. High levels of apoptosis were found at E11.5 and E13.5, but dropped to near-control levels by E16.5. The apoptosis at the early stage of neurogenesis occurred in both BrdU pulse-labeled neural progenitors and the neurons derived therefrom. No changes were observed in the mitotic index of apical (neuroepithelial, radial glial) progenitors and basal (intermediate) progenitors, indicating that Brca1 ablation did not affect cell cycle progression. Brca1 ablation did, however, result in the nuclear translocation of p53 in neural progenitors, suggesting that their apoptosis involved activation of the p53 pathway. Our results show that Brca1 is required for the cerebral cortex to develop to normal size by preventing the apoptosis of early cortical progenitors and their immediate progeny. PMID:19403657

  11. Characterization of an Italian Founder Mutation in the RING-Finger Domain of BRCA1

    PubMed Central

    Colombo, Mara; Congregati, Caterina; Sarkar, Mohosin; Magliery, Thomas J.; Ripamonti, Carla B.; Foglia, Claudia; Peissel, Bernard; Zaffaroni, Daniela; Manoukian, Siranoush; Tondini, Carlo; Barile, Monica; Pensotti, Valeria; Bernard, Loris

    2014-01-01

    The identification of founder mutations in cancer predisposing genes is important to improve risk assessment in geographically defined populations, since it may provide specific targets resulting in cost-effective genetic testing. Here, we report the characterization of the BRCA1 c.190T>C (p.Cys64Arg) mutation, mapped to the RING-finger domain coding region, that we detected in 43 hereditary breast/ovarian cancer (HBOC) families, for the large part originating from the province of Bergamo (Northern Italy). Haplotype analysis was performed in 21 families, and led to the identification of a shared haplotype extending over three BRCA1-associated marker loci (0.4 cM). Using the DMLE+2.2 software program and regional population demographic data, we were able to estimate the age of the mutation to vary between 3,100 and 3,350 years old. Functional characterization of the mutation was carried out at both transcript and protein level. Reverse transcriptase-PCR analysis on lymphoblastoid cells revealed expression of full length mRNA from the mutant allele. A green fluorescent protein (GFP)-fragment reassembly assay showed that the p.Cys64Arg substitution prevents the binding of the BRCA1 protein to the interacting protein BARD1, in a similar way as proven deleterious mutations in the RING-domain. Overall, 55 of 83 (66%) female mutation carriers had a diagnosis of breast and/or ovarian cancer. Our observations indicate that the BRCA1 c.190T>C is a pathogenic founder mutation present in the Italian population. Further analyses will evaluate whether screening for this mutation can be suggested as an effective strategy for the rapid identification of at-risk individuals in the Bergamo area. PMID:24516540

  12. CTLA-4 Blockade Synergizes Therapeutically with PARP Inhibition in BRCA1-Deficient Ovarian Cancer.

    PubMed

    Higuchi, Tomoe; Flies, Dallas B; Marjon, Nicole A; Mantia-Smaldone, Gina; Ronner, Lukas; Gimotty, Phyllis A; Adams, Sarah F

    2015-11-01

    Immune checkpoint blockade has shown significant therapeutic efficacy in melanoma and other solid tumors, but results in ovarian cancer have been limited. With evidence that tumor immunogenicity modulates the response to checkpoint blockade, and data indicating that BRCA-deficient ovarian cancers express higher levels of immune response genes, we hypothesized that BRCA(-) ovarian tumors would be vulnerable to checkpoint blockade. To test this hypothesis, we used an immunocompetent BRCA1-deficient murine ovarian cancer model to compare treatment with CTLA-4 or PD-1/PD-L1 antibodies alone or combined with targeted cytotoxic therapy using a PARP inhibitor. Correlative studies were performed in vitro using human BRCA1(-) cells. We found that CTLA-4 antibody, but not PD-1/PD-L1 blockade, synergized therapeutically with the PARP inhibitor, resulting in immune-mediated tumor clearance and long-term survival in a majority of animals (P < 0.0001). The survival benefit of this combination was T-cell mediated and dependent on increases in local IFNγ production in the peritoneal tumor environment. Evidence of protective immune memory was observed more than 60 days after completion of therapy. Similar increases in the cytotoxic effect of PARP inhibition in the presence of elevated levels of IFNγ in human BRCA1(-) cancer cells support the translational potential of this treatment protocol. These results demonstrate that CTLA-4 blockade combined with PARP inhibition induces protective antitumor immunity and significant survival benefit in the BRCA1(-) tumor model, and support clinical testing of this regimen to improve outcomes for women with hereditary ovarian cancer. PMID:26138335

  13. Polymorphisms in DNA Repair Pathway Genes, Body Mass Index, and Risk of Non-Hodgkin Lymphoma

    PubMed Central

    Chen, Yingtai; Zheng, Tongzhang; Lan, Qing; Kim, Christopher; Qin, Qin; Foss, Francine; Chen, Xuezhong; Holford, Theodore; Leaderer, Brian; Boyle, Peter; Wang, Chengfeng; Dai, Min; Liu, Zhenjiang; Ma, Shuangge; Chanock, Stephen J.; Rothman, Nathaniel; Zhang, Yawei

    2013-01-01

    We conducted a population-based case-control study in Connecticut women to test the hypothesis that genetic variations in DNA repair pathway genes may modify the relationship between body mass index (BMI) and risk of non-Hodgkin lymphoma (NHL). Compared to those with BMI < 25, women with BMI ≥ 25 had significantly increased risk of NHL among women who carried BRCA1 (rs799917) CT/TT, ERCC2 (rs13181) AA, XRCC1 (rs1799782) CC, and WRN (rs1801195) GG genotypes, but no increase in NHL risk among women who carried BRCA1 CC, ERCC2 AC/CC, XRCC1 CT/TT, and WRN GT/TT genotypes. A significant interaction with BMI was only observed for WRN (rs1801195, P=0.004) for T-cell lymphoma and ERCC2 (rs13181, P=0.002) for diffuse large B-cell lymphoma. The results suggest that common genetic variation in DNA repair pathway genes may modify the association between BMI and NHL risk. PMID:23619945

  14. Characteristics of BRCA1/2 Mutation-Positive Breast Cancers in Korea: A Comparison Study Based on Multicenter Data and the Korean Breast Cancer Registry

    PubMed Central

    Yu, Jong-Han; Son, Byung Ho; Kim, Sung-Won; Park, Sue K.; Lee, Min Hyuk; Kim, Lee Su; Noh, Woo-Chul; Kim, Eun-Kyu; Yoon, Dae Sung; Lee, Jeeyeon; Jung, Jin Hyang; Jung, Sang Seol; Gong, Gyungyup; Ahn, Sei-Hyun

    2014-01-01

    Purpose Mutations in BRCA genes are the main cause of hereditary breast cancer in Korea. The aim of this study was to investigate the characteristics of breast cancers involving BRCA1 (BRCA1 group) and BRCA2 (BRCA2 group) mutations. Methods We retrospectively reviewed the medical records of patients with BRCA1 (BRCA1 group) or BRCA2 (BRCA2 group) mutation positive breast cancer from multiple centers and compared the data to that of the Korean Breast Cancer Society registry (registry group). Results The patients of the BRCA1 group were diagnosed at a younger age (median age, 37 years) and had tumors of higher histological (61.3% with histological grade 3) and nuclear (37.5% with nuclear grade 3) grade than those of the registry group. In addition, the frequency of ductal carcinoma in situ in the BRCA1 group was lower (3.7%) than in the registry group, and the BRCA1 group were more likely to be triple-negative breast cancer (61.3%). Patients in the BRCA2 group were also younger at diagnosis (mean age, 41 years) and were more likely to have involvement of the axillary node than the registry group (45.5% vs. 33.5%, p=0.002). The BRCA1 and BRCA2 groups did not show a correlation between tumor size and axillary node involvement. Conclusion We report the characteristics of BRCA mutation positive breast cancer patients in the Korean population through multicenter data and nation-wide breast cancer registry study. However, BRCA-mutated breast cancers appear highly complex, and further research on their molecular basis is needed in Korea. PMID:25013433

  15. Increased Chromosomal Radiosensitivity in Women Carrying BRCA1/BRCA2 Mutations Assessed With the G2 Assay

    SciTech Connect

    Ernestos, Beroukas; Nikolaos, Pandis; Koulis, Giannoukakos; Eleni, Rizou; Konstantinos, Beroukas; Alexandra, Giatromanolaki; Michael, Koukourakis

    2010-03-15

    Purpose: Several in vitro studies suggest that BRCA1 and BRCA2 mutation carriers present increased sensitivity to ionizing radiation. Different assays for the assessment of deoxyribonucleic acid double-strand break repair capacity have been used, but results are rather inconsistent. Given the concerns about the possible risks of breast screening with mammography in mutation carrier women and the potentially damaging effects of radiotherapy, the purpose of this study was to further investigate the radiosensitivity of this population. Methods and Materials: The G2 chromosomal radiosensitivity assay was used to assess chromosomal breaks in lymphocyte cultures after exposure to 1 Gy. A group of familiar breast cancer patients carrying a mutation in the BRCA1 or BRCA2 gene (n = 15) and a group of healthy mutation carriers (n = 5) were investigated and compared with a reference group of healthy women carrying no mutation (n = 21). Results: BRCA1 and BRCA2 mutation carriers had a significantly higher number of mean chromatid breaks per cell (p = 0.006) and a higher maximum number of breaks (p = 0.0001) as compared with their matched controls. Both healthy carriers and carriers with a cancer history were more radiosensitive than controls (p = 0.002 and p = 0.025, respectively). Age was not associated with increased radiosensitivity (p = 0.868). Conclusions: Our results indicate that BRCA1 and BRCA2 mutation carriers show enhanced radiosensitivity, presumably because of the involvement of the BRCA genes in deoxyribonucleic acid repair and cell cycle control mechanisms.

  16. BRCA1 maps proximal to D17S579 on chromosome 17q21 by genetic analysis

    PubMed Central

    Chamberlain, Jeffrey S.; Boehnke, Michael; Frank, Thomas S.; Kiousis, Sam; Xu, Junxhe; Guo, Sun-Wei; Hauser, Elizabeth R.; Norum, Robert A.; Helmbold, Elizabeth A.; Markel, Dorene S.; Keshavarzi, Sima M.; Jackson, C. Eugene; Calzone, Kathleen; Garber, Judy; Collins, Francis S.; Weber, Barbara L.

    1993-01-01

    Previous studies have demonstrated linkage between early-onset breast cancer and ovarian cancer and genetic markers on chromosome 17q21. These markers define the location of a gene (BRCA1) which appears to be inherited as an autosomal dominant susceptibility allele. We analyzed five families with multiple affected individuals for evidence of linkage to the BRCA1 region. Two of the five families appear to be linked to BRCA1. One apparently linked family contains critical recombinants, suggesting that the gene is proximal to the marker D17S579 (Mfd188). These findings are consistent with the maximum-likelihood position estimated by the Breast Cancer Linkage Consortium and with recombination events detected in other linked families. Linkage analysis was greatly aided by PCR-based analysis of paraffin-embedded normal breast tissue from deceased family members, demonstrating the feasibility and importance of this approach. One of the two families with evidence of linkage between breast cancer and genetic markers flanking BRCA1 represents the first such family of African-American descent to be reported in detail. ImagesFigure 4 PMID:8460646

  17. BRCA1 interacts with Nrf2 to regulate antioxidant signaling and cell survival

    PubMed Central

    Gorrini, Chiara; Baniasadi, Pegah S.; Harris, Isaac S.; Silvester, Jennifer; Inoue, Satoshi; Snow, Bryan; Joshi, Purna A.; Wakeham, Andrew; Molyneux, Sam D.; Martin, Bernard; Bouwman, Peter; Cescon, David W.; Elia, Andrew J.; Winterton-Perks, Zoe; Cruickshank, Jennifer; Brenner, Dirk; Tseng, Alan; Musgrave, Melinda; Berman, Hal K.; Khokha, Rama; Jonkers, Jos

    2013-01-01

    Oxidative stress plays an important role in cancer development and treatment. Recent data implicate the tumor suppressor BRCA1 in regulating oxidative stress, but the molecular mechanism and the impact in BRCA1-associated tumorigenesis remain unclear. Here, we show that BRCA1 regulates Nrf2-dependent antioxidant signaling by physically interacting with Nrf2 and promoting its stability and activation. BRCA1-deficient mouse primary mammary epithelial cells show low expression of Nrf2-regulated antioxidant enzymes and accumulate reactive oxygen species (ROS) that impair survival in vivo. Increased Nrf2 activation rescues survival and ROS levels in BRCA1-null cells. Interestingly, 53BP1 inactivation, which has been shown to alleviate several defects associated with BRCA1 loss, rescues survival of BRCA1-null cells without restoring ROS levels. We demonstrate that estrogen treatment partially restores Nrf2 levels in the absence of BRCA1. Our data suggest that Nrf2-regulated antioxidant response plays a crucial role in controlling survival downstream of BRCA1 loss. The ability of estrogen to induce Nrf2 posits an involvement of an estrogen-Nrf2 connection in BRCA1 tumor suppression. Lastly, BRCA1-mutated tumors retain a defective antioxidant response that increases the sensitivity to oxidative stress. In conclusion, the role of BRCA1 in regulating Nrf2 activity suggests important implications for both the etiology and treatment of BRCA1-related cancers. PMID:23857982

  18. BRCA1 and CtIP promote alternative non-homologous end-joining at uncapped telomeres.

    PubMed

    Badie, Sophie; Carlos, Ana Rita; Folio, Cecilia; Okamoto, Keiji; Bouwman, Peter; Jonkers, Jos; Tarsounas, Madalena

    2015-02-01

    Loss of telomere protection occurs during physiological cell senescence and ageing, due to attrition of telomeric repeats and insufficient retention of the telomere-binding factor TRF2. Subsequently formed telomere fusions trigger rampant genomic instability leading to cell death or tumorigenesis. Mechanistically, telomere fusions require either the classical non-homologous end-joining (C-NHEJ) pathway dependent on Ku70/80 and LIG4, or the alternative non-homologous end-joining (A-NHEJ), which relies on PARP1 and LIG3. Here, we show that the tumour suppressor BRCA1, together with its interacting partner CtIP, both acting in end resection, also promotes end-joining of uncapped telomeres. BRCA1 and CtIP do not function in the ATM-dependent telomere damage signalling, nor in telomere overhang removal, which are critical for telomere fusions by C-NHEJ. Instead, BRCA1 and CtIP act in the same pathway as LIG3 to promote joining of de-protected telomeres by A-NHEJ. Our work therefore ascribes novel roles for BRCA1 and CtIP in end-processing and fusion reactions at uncapped telomeres, underlining the complexity of DNA repair pathways that act at chromosome ends lacking protective structures. Moreover, A-NHEJ provides a mechanism of previously unanticipated significance in telomere dysfunction-induced genome instability. PMID:25582120

  19. Timing of oral contraceptive use and the risk of breast cancer in BRCA1 mutation carriers.

    PubMed

    Kotsopoulos, Joanne; Lubinski, Jan; Moller, Pal; Lynch, Henry T; Singer, Christian F; Eng, Charis; Neuhausen, Susan L; Karlan, Beth; Kim-Sing, Charmaine; Huzarski, Tomasz; Gronwald, Jacek; McCuaig, Jeanna; Senter, Leigha; Tung, Nadine; Ghadirian, Parviz; Eisen, Andrea; Gilchrist, Dawna; Blum, Joanne L; Zakalik, Dana; Pal, Tuya; Sun, Ping; Narod, Steven A

    2014-02-01

    It is not clear if early oral contraceptive use increases the risk of breast cancer among young women with a breast cancer susceptibility gene 1 (BRCA1) mutation. Given the benefit of oral contraceptives for the prevention of ovarian cancer, estimating age-specific risk ratios for oral contraceptive use and breast cancer is important. We conducted a case-control study of 2,492 matched pairs of women with a deleterious BRCA1 mutation. Breast cancer cases and unaffected controls were matched on year of birth and country of residence. Detailed information about oral contraceptive use was collected from a routinely administered questionnaire. Conditional logistic regression was used to estimate the odds ratios (OR) and 95 % confidence intervals (CI) for the association between oral contraceptive and breast cancer, by age at first use and by age at diagnosis. Among BRCA1 mutation carriers, oral contraceptive use was significantly associated with an increased risk of breast cancer for women who started the pill prior to age 20 (OR 1.45; 95 % CI 1.20-1.75; P = 0.0001) and possibly between ages 20 and 25 as well (OR 1.19; 95 % CI 0.99-1.42; P = 0.06). The effect was limited to breast cancers diagnosed before age 40 (OR 1.40; 95 % CI 1.14-1.70; P = 0.001); the risk of early-onset breast cancer increased by 11 % with each additional year of pill use when initiated prior to age 20 (OR 1.11; 95 % CI 1.03-1.20; P = 0.008). There was no observed increase for women diagnosed at or after the age of 40 (OR 0.97; 95 % CI 0.79-1.20; P = 0.81). Oral contraceptive use before age 25 increases the risk of early-onset breast cancer among women with a BRCA1 mutation and the risk increases with duration of use. Caution should be taken when advising women with a BRCA1 mutation to take an oral contraceptive prior to age 25. PMID:24458845

  20. Evaluation of a candidate breast cancer associated SNP in ERCC4 as a risk modifier in BRCA1 and BRCA2 mutation carriers. Results from the Consortium of Investigators of Modifiers of BRCA1/BRCA2 (CIMBA)

    PubMed Central

    Osorio, A; Milne, R L; Pita, G; Peterlongo, P; Heikkinen, T; Simard, J; Chenevix-Trench, G; Spurdle, A B; Beesley, J; Chen, X; Healey, S; Neuhausen, S L; Ding, Y C; Couch, F J; Wang, X; Lindor, N; Manoukian, S; Barile, M; Viel, A; Tizzoni, L; Szabo, C I; Foretova, L; Zikan, M; Claes, K; Greene, M H; Mai, P; Rennert, G; Lejbkowicz, F; Barnett-Griness, O; Andrulis, I L; Ozcelik, H; Weerasooriya, N; Gerdes, A-M; Thomassen, M; Cruger, D G; Caligo, M A; Friedman, E; Kaufman, B; Laitman, Y; Cohen, S; Kontorovich, T; Gershoni-Baruch, R; Dagan, E; Jernström, H; Askmalm, M S; Arver, B; Malmer, B; Domchek, S M; Nathanson, K L; Brunet, J; Ramón y Cajal, T; Yannoukakos, D; Hamann, U; Hogervorst, F B L; Verhoef, S; García, EB Gómez; Wijnen, J T; van den Ouweland, A; Easton, D F; Peock, S; Cook, M; Oliver, C T; Frost, D; Luccarini, C; Evans, D G; Lalloo, F; Eeles, R; Pichert, G; Cook, J; Hodgson, S; Morrison, P J; Douglas, F; Godwin, A K; Sinilnikova, O M; Barjhoux, L; Stoppa-Lyonnet, D; Moncoutier, V; Giraud, S; Cassini, C; Olivier-Faivre, L; Révillion, F; Peyrat, J-P; Muller, D; Fricker, J-P; Lynch, H T; John, E M; Buys, S; Daly, M; Hopper, J L; Terry, M B; Miron, A; Yassin, Y; Goldgar, D; Singer, C F; Gschwantler-Kaulich, D; Pfeiler, G; Spiess, A-C; Hansen, Thomas v O; Johannsson, O T; Kirchhoff, T; Offit, K; Kosarin, K; Piedmonte, M; Rodriguez, G C; Wakeley, K; Boggess, J F; Basil, J; Schwartz, P E; Blank, S V; Toland, A E; Montagna, M; Casella, C; Imyanitov, E N; Allavena, A; Schmutzler, R K; Versmold, B; Engel, C; Meindl, A; Ditsch, N; Arnold, N; Niederacher, D; Deißler, H; Fiebig, B; Varon-Mateeva, R; Schaefer, D; Froster, U G; Caldes, T; de la Hoya, M; McGuffog, L; Antoniou, A C; Nevanlinna, H; Radice, P; Benítez, J

    2009-01-01

    Background: In this study we aimed to evaluate the role of a SNP in intron 1 of the ERCC4 gene (rs744154), previously reported to be associated with a reduced risk of breast cancer in the general population, as a breast cancer risk modifier in BRCA1 and BRCA2 mutation carriers. Methods: We have genotyped rs744154 in 9408 BRCA1 and 5632 BRCA2 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) and assessed its association with breast cancer risk using a retrospective weighted cohort approach. Results: We found no evidence of association with breast cancer risk for BRCA1 (per-allele HR: 0.98, 95% CI: 0.93–1.04, P=0.5) or BRCA2 (per-allele HR: 0.97, 95% CI: 0.89–1.06, P=0.5) mutation carriers. Conclusion: This SNP is not a significant modifier of breast cancer risk for mutation carriers, though weak associations cannot be ruled out. PMID:19920816

  1. Post-mortem testing; germline BRCA1/2 variant detection using archival FFPE non-tumor tissue. A new paradigm in genetic counseling.

    PubMed

    Petersen, Annabeth Høgh; Aagaard, Mads Malik; Nielsen, Henriette Roed; Steffensen, Karina Dahl; Waldstrøm, Marianne; Bojesen, Anders

    2016-08-01

    Accurate estimation of cancer risk in HBOC families often requires BRCA1/2 testing, but this may be impossible in deceased family members. Previous, testing archival formalin-fixed, paraffin-embedded (FFPE) tissue for germline BRCA1/2 variants was unsuccessful, except for the Jewish founder mutations. A high-throughput method to systematically test for variants in all coding regions of BRCA1/2 in archival FFPE samples of non-tumor tissue is described, using HaloPlex target enrichment and next-generation sequencing. In a validation study, correct identification of variants or wild-type was possible in 25 out of 30 (83%) FFPE samples (age range 1-14 years), with a known variant status in BRCA1/2. No false positive was found. Unsuccessful identification was due to highly degraded DNA or presence of large intragenic deletions. In clinical use, a total of 201 FFPE samples (aged 0-43 years) were processed. Thirty-six samples were rejected because of highly degraded DNA or failed library preparation. Fifteen samples were investigated to search for a known variant. In the remaining 150 samples (aged 0-38 years), three variants known to affect function and one variant likely to affect function in BRCA1, six variants known to affect function and one variant likely to affect function in BRCA2, as well as four variants of unknown significance (VUS) in BRCA1 and three VUS in BRCA2 were discovered. It is now possible to test for germline BRCA1/2 variants in deceased persons, using archival FFPE samples from non-tumor tissue. Accurate genetic counseling is achievable in families where variant testing would otherwise be impossible. PMID:26733283

  2. Gene-gene interactions in breast cancer susceptibility.

    PubMed

    Turnbull, Clare; Seal, Sheila; Renwick, Anthony; Warren-Perry, Margaret; Hughes, Deborah; Elliott, Anna; Pernet, David; Peock, Susan; Adlard, Julian W; Barwell, Julian; Berg, Jonathan; Brady, Angela F; Brewer, Carole; Brice, Glen; Chapman, Cyril; Cook, Jackie; Davidson, Rosemarie; Donaldson, Alan; Douglas, Fiona; Greenhalgh, Lynn; Henderson, Alex; Izatt, Louise; Kumar, Ajith; Lalloo, Fiona; Miedzybrodzka, Zosia; Morrison, Patrick J; Paterson, Joan; Porteous, Mary; Rogers, Mark T; Shanley, Susan; Walker, Lisa; Ahmed, Munaza; Eccles, Diana; Evans, D Gareth; Donnelly, Peter; Easton, Douglas F; Stratton, Michael R; Rahman, Nazneen

    2012-02-15

    There have been few definitive examples of gene-gene interactions in humans. Through mutational analyses in 7325 individuals, we report four interactions (defined as departures from a multiplicative model) between mutations in the breast cancer susceptibility genes ATM and CHEK2 with BRCA1 and BRCA2 (case-only interaction between ATM and BRCA1/BRCA2 combined, P = 5.9 × 10(-4); ATM and BRCA1, P= 0.01; ATM and BRCA2, P= 0.02; CHEK2 and BRCA1/BRCA2 combined, P = 2.1 × 10(-4); CHEK2 and BRCA1, P= 0.01; CHEK2 and BRCA2, P= 0.01). The interactions are such that the resultant risk of breast cancer is lower than the multiplicative product of the constituent risks, and plausibly reflect the functional relationships of the encoded proteins in DNA repair. These findings have important implications for models of disease predisposition and clinical translation. PMID:22072393

  3. Phosphatidylinositol 3-kinase/Akt signaling enhances nuclear localization and transcriptional activity of BRCA1

    SciTech Connect

    Hinton, Cimona V.; Fitzgerald, Latricia D.; Thompson, Marilyn E. . E-mail: methompson@mmc.edu

    2007-05-15

    Signaling pathways involved in regulating nuclear-cytoplasmic distribution of BRCA1 have not been previously reported. Here, we provide evidence that heregulin {beta}1-induced activation of the Akt pathway increases the nuclear content of BRCA1. First, treatment of T47D breast cancer cells with heregulin {beta}1 results in a two-fold increase in nuclear BRCA1 as assessed by FACS analysis, immunoblotting and immunofluorescence. This heregulin-induced increase in nuclear BRCA1 is blocked by siRNA-mediated down-regulation of Akt. Second, mutation of threonine 509 in BRCA1, the site of Akt phosphorylation, to an alanine, attenuates the ability of heregulin to induce BRCA1 nuclear accumulation. These data suggest that Akt-catalyzed phosphorylation of BRCA1 is required for the heregulin-regulated nuclear concentration of BRCA1. Because most functions ascribed to BRCA1 occur within the nucleus, we postulated that phosphorylation-dependent nuclear accumulation of BRCA1 would result in enhanced nuclear activity, specifically transcriptional activity, of BRCA1. This postulate is affirmed by our observation that the ability of BRCA1 to transactivate GADD45 promoter constructs was enhanced in T47D cells treated with heregulin {beta}1. Furthermore, the heterologous expression of BRCA1 in HCC1937 human breast cancer cells, which have constitutively active Akt, also induces GADD45 promoter activity, whereas the expression of BRCA1 in which threonine 509 has been mutated to an alanine is able to only minimally induce promoter activity. These findings implicate Akt in upstream events leading to BRCA1 nuclear localization and function.

  4. Phosphatidylinositol 3-kinase/Akt signaling enhances nuclear localization and transcriptional activity of BRCA1

    PubMed Central

    Hinton, Cimona V.; Fitzgerald, Latricia D.; Thompson, Marilyn E.

    2007-01-01

    Signaling pathways involved in regulating nuclear-cytoplasmic distribution of BRCA1 have not been previously reported. Here, we provide evidence that heregulin β1-induced activation of the Akt pathway increases the nuclear content of BRCA1. First, treatment of T47D breast cancer cells with heregulin β1 results in a two-fold increase in nuclear BRCA1 as assessed by FACS analysis, immunoblotting and immunofluorescence. This heregulin-induced increase in nuclear BRCA1 is blocked by siRNA-mediated down-regulation of Akt. Second, mutation of threonine 509 in BRCA1, the site of Akt phosphorylation, to an alanine, attenuates the ability of heregulin to induce BRCA1 nuclear accumulation. These data suggest that Akt-catalyzed phosphorylation of BRCA1 is required for the heregulin-regulated nuclear concentration of BRCA1. Because most functions ascribed to BRCA1 occur within the nucleus, we postulated that phosphorylation-dependent nuclear accumulation of BRCA1 would result in enhanced nuclear activity, specifically transcriptional activity, of BRCA1. This postulate is affirmed by our observation that the ability of BRCA1 to transactivate GADD45 promoter constructs was enhanced in T47D cells treated with heregulin β1. Furthermore, the heterologous expression of BRCA1 in HCC1937 human breast cancer cells, which have constitutively active Akt, also induces GADD45 promoter activity, whereas the expression of BRCA1 in which threonine 509 has been mutated to an alanine is able to only minimally induce promoter activity. These findings implicate Akt in upstream events leading to BRCA1 nuclear localization and function. PMID:17428466

  5. Haplotype and quantitative transcript analyses of Portuguese breast/ovarian cancer families with the BRCA1 R71G founder mutation of Galician origin.

    PubMed

    Santos, Catarina; Peixoto, Ana; Rocha, Patrícia; Vega, Ana; Soares, Maria José; Cerveira, Nuno; Bizarro, Susana; Pinheiro, Manuela; Pereira, Deolinda; Rodrigues, Helena; Castro, Fernando; Henrique, Rui; Teixeira, Manuel R

    2009-01-01

    We investigated the functional effect of the missense variant c.211A>G (R71G) localized at position -2 of exon 5 donor splice site in the BRCA1 gene and evaluated whether Portuguese and Galician families with this mutation share a common ancestry. Three unrelated Portuguese breast/ovarian cancer families carrying this variant were studied through qualitative and quantitative transcript analyses. We also evaluated the presence of loss of heterozigosity and the histopathologic characteristics of the carcinomas in those families. Informative families (two from Portugal and one from Galicia) were genotyped for polymorphic microsatellite markers flanking BRCA1 to reconstruct haplotypes. Qualitative RNA analysis revealed the presence of two alternative transcripts both in carriers of the BRCA1 R71G variant and in controls. Semi-quantitative fragment analysis and real-time RT-PCR showed a significant increase of the transcript with an out of frame deletion of the last 22nt of exon 5 (BRCA1-Delta22ntex5) and a decrease of the full-length transcript (BRCA1-ex5FL) in patients carrying the R71G mutation as compared to controls, whereas no significant differences were found for the transcript with in frame skipping of exon 5 (BRCA1-Deltaex5). One haplotype was found to segregate in the two informative Portuguese families and in the Galician family. We demonstrate that disruption of alternative transcript ratios is the mechanism causing hereditary breast/ovarian cancer associated with the BRCA1 R71G mutation. Furthermore, our findings indicate a common ancestry of the Portuguese and Galician families sharing this mutation. PMID:19123044

  6. Assessing Associations between the AURKA-HMMR-TPX2-TUBG1 Functional Module and Breast Cancer Risk in BRCA1/2 Mutation Carriers

    PubMed Central

    Blanco, Ignacio; Kuchenbaecker, Karoline; Cuadras, Daniel; Wang, Xianshu; Barrowdale, Daniel; de Garibay, Gorka Ruiz; Librado, Pablo; Sánchez-Gracia, Alejandro; Rozas, Julio; Bonifaci, Núria; McGuffog, Lesley; Pankratz, Vernon S.; Islam, Abul; Mateo, Francesca; Berenguer, Antoni; Petit, Anna; Català, Isabel; Brunet, Joan; Feliubadaló, Lidia; Tornero, Eva; Benítez, Javier; Osorio, Ana; Cajal, Teresa Ramón y; Nevanlinna, Heli; Aittomäki, Kristiina; Arun, Banu K.; Toland, Amanda E.; Karlan, Beth Y.; Walsh, Christine; Lester, Jenny; Greene, Mark H.; Mai, Phuong L.; Nussbaum, Robert L.; Andrulis, Irene L.; Domchek, Susan M.; Nathanson, Katherine L.; Rebbeck, Timothy R.; Barkardottir, Rosa B.; Jakubowska, Anna; Lubinski, Jan; Durda, Katarzyna; Jaworska-Bieniek, Katarzyna; Claes, Kathleen; Van Maerken, Tom; Díez, Orland; Hansen, Thomas V.; Jønson, Lars; Gerdes, Anne-Marie; Ejlertsen, Bent; de la Hoya, Miguel; Caldés, Trinidad; Dunning, Alison M.; Oliver, Clare; Fineberg, Elena; Cook, Margaret; Peock, Susan; McCann, Emma; Murray, Alex; Jacobs, Chris; Pichert, Gabriella; Lalloo, Fiona; Chu, Carol; Dorkins, Huw; Paterson, Joan; Ong, Kai-Ren; Teixeira, Manuel R.; Hogervorst, Frans B. L.; van der Hout, Annemarie H.; Seynaeve, Caroline; van der Luijt, Rob B.; Ligtenberg, Marjolijn J. L.; Devilee, Peter; Wijnen, Juul T.; Rookus, Matti A.; Meijers-Heijboer, Hanne E. J.; Blok, Marinus J.; van den Ouweland, Ans M. W.; Aalfs, Cora M.; Rodriguez, Gustavo C.; Phillips, Kelly-Anne A.; Piedmonte, Marion; Nerenstone, Stacy R.; Bae-Jump, Victoria L.; O'Malley, David M.; Ratner, Elena S.; Schmutzler, Rita K.; Wappenschmidt, Barbara; Rhiem, Kerstin; Engel, Christoph; Meindl, Alfons; Ditsch, Nina; Arnold, Norbert; Plendl, Hansjoerg J.; Niederacher, Dieter; Sutter, Christian; Wang-Gohrke, Shan; Steinemann, Doris; Preisler-Adams, Sabine; Kast, Karin; Varon-Mateeva, Raymonda; Gehrig, Andrea; Bojesen, Anders; Pedersen, Inge Sokilde; Sunde, Lone; Jensen, Uffe Birk; Thomassen, Mads; Kruse, Torben A.; Foretova, Lenka; Peterlongo, Paolo; Bernard, Loris; Peissel, Bernard; Scuvera, Giulietta; Manoukian, Siranoush; Radice, Paolo; Ottini, Laura; Montagna, Marco; Agata, Simona; Maugard, Christine; Simard, Jacques; Soucy, Penny; Berger, Andreas; Fink-Retter, Anneliese; Singer, Christian F.; Rappaport, Christine; Geschwantler-Kaulich, Daphne; Tea, Muy-Kheng; Pfeiler, Georg; John, Esther M.; Miron, Alex; Neuhausen, Susan L.; Terry, Mary Beth; Chung, Wendy K.; Daly, Mary B.; Goldgar, David E.; Janavicius, Ramunas; Dorfling, Cecilia M.; van Rensburg, Elisabeth J.; Fostira, Florentia; Konstantopoulou, Irene; Garber, Judy; Godwin, Andrew K.; Olah, Edith; Narod, Steven A.; Rennert, Gad; Paluch, Shani Shimon; Laitman, Yael; Friedman, Eitan; Liljegren, Annelie; Rantala, Johanna; Stenmark-Askmalm, Marie; Loman, Niklas; Imyanitov, Evgeny N.; Hamann, Ute; Spurdle, Amanda B.; Healey, Sue; Weitzel, Jeffrey N.; Herzog, Josef; Margileth, David; Gorrini, Chiara; Esteller, Manel; Gómez, Antonio; Sayols, Sergi; Vidal, Enrique; Heyn, Holger; Stoppa-Lyonnet, Dominique; Léoné, Melanie; Barjhoux, Laure; Fassy-Colcombet, Marion; de Pauw, Antoine; Lasset, Christine; Ferrer, Sandra Fert; Castera, Laurent; Berthet, Pascaline; Cornelis, François; Bignon, Yves-Jean; Damiola, Francesca; Mazoyer, Sylvie; Maxwell, Christopher A.; Vijai, Joseph; Robson, Mark; Kauff, Noah; Corines, Marina J.; Villano, Danylko; Cunningham, Julie; Lee, Adam; Lindor, Noralane; Lázaro, Conxi; Easton, Douglas F.; Offit, Kenneth; Chenevix-Trench, Georgia; Couch, Fergus J.; Antoniou, Antonis C.; Pujana, Miguel Angel

    2015-01-01

    While interplay between BRCA1 and AURKA-RHAMM-TPX2-TUBG1 regulates mammary epithelial polarization, common genetic variation in HMMR (gene product RHAMM) may be associated with risk of breast cancer in BRCA1 mutation carriers. Following on these observations, we further assessed the link between the AURKA-HMMR-TPX2-TUBG1 functional module and risk of breast cancer in BRCA1 or BRCA2 mutation carriers. Forty-one single nucleotide polymorphisms (SNPs) were genotyped in 15,252 BRCA1 and 8,211 BRCA2 mutation carriers and subsequently analyzed using a retrospective likelihood approach. The association of HMMR rs299290 with breast cancer risk in BRCA1 mutation carriers was confirmed: per-allele hazard ratio (HR) = 1.10, 95% confidence interval (CI) 1.04 – 1.15, p = 1.9 x 10−4 (false discovery rate (FDR)-adjusted p = 0.043). Variation in CSTF1, located next to AURKA, was also found to be associated with breast cancer risk in BRCA2 mutation carriers: rs2426618 per-allele HR = 1.10, 95% CI 1.03 – 1.16, p = 0.005 (FDR-adjusted p = 0.045). Assessment of pairwise interactions provided suggestions (FDR-adjusted pinteraction values > 0.05) for deviations from the multiplicative model for rs299290 and CSTF1 rs6064391, and rs299290 and TUBG1 rs11649877 in both BRCA1 and BRCA2 mutation carriers. Following these suggestions, the expression of HMMR and AURKA or TUBG1 in sporadic breast tumors was found to potentially interact, influencing patients’ survival. Together, the results of this study support the hypothesis of a causative link between altered function of AURKA-HMMR-TPX2-TUBG1 and breast carcinogenesis in BRCA1/2 mutation carriers. PMID:25830658

  7. MicroRNA deregulation in triple negative breast cancer reveals a role of miR-498 in regulating BRCA1 expression

    PubMed Central

    Matamala, Nerea; Vargas, Maria Teresa; González-Cámpora, Ricardo; Arias, Jose Ignacio; Menéndez, Primitiva; Andrés-León, Eduardo; Yanowsky, Kira; Llaneza-Folgueras, Ana; Miñambres, Rebeca; Martínez-Delgado, Beatriz; Benítez, Javier

    2016-01-01

    Emerging evidence suggests that BRCA1 pathway contributes to the behavior of sporadic triple negative breast cancer (TNBC), but little is known about the mechanisms underlying this association. Considering the central role that microRNAs (miRNAs) play in gene expression regulation, the aim of this study was to identify miRNAs specifically deregulated in TNBC and investigate their involvement in BRCA1 regulation. Using locked nucleic acid (LNA)-based microarrays, expression levels of 1919 miRNAs were measured in paraffin-embedded tissues from 122 breast tumors and 11 healthy breast tissue samples. Differential miRNA expression was explored among the main subtypes of breast cancer, and 105 miRNAs were identified as specific for triple negative tumors. In silico prediction revealed that miR-498 and miR-187-5p target BRCA1, and these results were confirmed by luciferase reporter assay. While miR-187-5p was found overexpressed in a luminal B cell line, miR-498 was highly expressed in a triple negative cell line, Hs578T, and its expression was negatively correlated with the levels of BRCA1. We functionally demonstrated that miR-498 inhibits BRCA1 in breast cancer cell lines, and showed that inhibition of miR-498 led to reduced proliferation in the triple negative cell line Hs578T. Our results indicate that miR-498 regulates BRCA1 expression in breast cancer and its overexpression could contribute to the pathogenesis of sporadic TNBC via BRCA1 downregulation. PMID:26933805

  8. ‘My funky genetics’: BRCA1/2 mutation carriers’ understanding of genetic inheritance and reproductive merger in the context of new repro-genetic technologies

    PubMed Central

    Rubin, Lisa R.; Doyle, Maya; Stern, Rikki; Savin, Katie; Hurley, Karen; Sagi, Michal

    2014-01-01

    INTRODUCTION Deleterious mutations in the BRCA1/BRCA2 genes elevate lifetime risk of breast and ovarian cancer. Each child of a mutation-positive parent has a 50% chance of inheriting it. Pre-implantation genetic diagnosis (PGD) permits prospective parents to avoid transmitting a BRCA1/2 mutation to a child, introducing predictability into a process historically defined by chance. This investigation explored how BRCA1/2 mutation carriers understand genetic inheritance and consider a child’s inheritance of a BRCA1/2 mutation, given the opportunities that exist to pursue PGD. METHOD 39 female and male BRCA1/2 mutation carriers of reproductive age were recruited from urban cancer and reproductive medical centers. Participants completed a standardized educational presentation on PGD and prenatal diagnosis, with pre- and post-test assessments. An interdisciplinary team of qualitative researchers analyzed data using grounded theory techniques. FINDINGS Participants expressed the belief that reproduction yields children with unique genetic strengths and challenges, including the BRCA1/2 mutation, family traits for which predictive tests do not exist, and hypothetical genetic risks. Participants expressed preference for biologically-related children, yet stated their genetically ‘well’ partner’s lineage would be marred through reproductive merger, requiring the well partner to assume the burden of the BRCA1/2 mutation via their children. Participants expressed diverse views of genetically ‘well’ partners’ participation in family planning and risk management decisions. DISCUSSION Pressure to use reprogenetic technology may grow as genetic susceptibility testing becomes more widely available. Work with individuals and couples across the disease spectrum must be attuned to they ways beliefs about genetic inheritance play into reproductive decision making. PMID:22709328

  9. Assessing associations between the AURKA-HMMR-TPX2-TUBG1 functional module and breast cancer risk in BRCA1/2 mutation carriers.

    PubMed

    Blanco, Ignacio; Kuchenbaecker, Karoline; Cuadras, Daniel; Wang, Xianshu; Barrowdale, Daniel; de Garibay, Gorka Ruiz; Librado, Pablo; Sánchez-Gracia, Alejandro; Rozas, Julio; Bonifaci, Núria; McGuffog, Lesley; Pankratz, Vernon S; Islam, Abul; Mateo, Francesca; Berenguer, Antoni; Petit, Anna; Català, Isabel; Brunet, Joan; Feliubadaló, Lidia; Tornero, Eva; Benítez, Javier; Osorio, Ana; Ramón y Cajal, Teresa; Nevanlinna, Heli; Aittomäki, Kristiina; Arun, Banu K; Toland, Amanda E; Karlan, Beth Y; Walsh, Christine; Lester, Jenny; Greene, Mark H; Mai, Phuong L; Nussbaum, Robert L; Andrulis, Irene L; Domchek, Susan M; Nathanson, Katherine L; Rebbeck, Timothy R; Barkardottir, Rosa B; Jakubowska, Anna; Lubinski, Jan; Durda, Katarzyna; Jaworska-Bieniek, Katarzyna; Claes, Kathleen; Van Maerken, Tom; Díez, Orland; Hansen, Thomas V; Jønson, Lars; Gerdes, Anne-Marie; Ejlertsen, Bent; de la Hoya, Miguel; Caldés, Trinidad; Dunning, Alison M; Oliver, Clare; Fineberg, Elena; Cook, Margaret; Peock, Susan; McCann, Emma; Murray, Alex; Jacobs, Chris; Pichert, Gabriella; Lalloo, Fiona; Chu, Carol; Dorkins, Huw; Paterson, Joan; Ong, Kai-Ren; Teixeira, Manuel R; Hogervorst, Frans B L; van der Hout, Annemarie H; Seynaeve, Caroline; van der Luijt, Rob B; Ligtenberg, Marjolijn J L; Devilee, Peter; Wijnen, Juul T; Rookus, Matti A; Meijers-Heijboer, Hanne E J; Blok, Marinus J; van den Ouweland, Ans M W; Aalfs, Cora M; Rodriguez, Gustavo C; Phillips, Kelly-Anne A; Piedmonte, Marion; Nerenstone, Stacy R; Bae-Jump, Victoria L; O'Malley, David M; Ratner, Elena S; Schmutzler, Rita K; Wappenschmidt, Barbara; Rhiem, Kerstin; Engel, Christoph; Meindl, Alfons; Ditsch, Nina; Arnold, Norbert; Plendl, Hansjoerg J; Niederacher, Dieter; Sutter, Christian; Wang-Gohrke, Shan; Steinemann, Doris; Preisler-Adams, Sabine; Kast, Karin; Varon-Mateeva, Raymonda; Gehrig, Andrea; Bojesen, Anders; Pedersen, Inge Sokilde; Sunde, Lone; Jensen, Uffe Birk; Thomassen, Mads; Kruse, Torben A; Foretova, Lenka; Peterlongo, Paolo; Bernard, Loris; Peissel, Bernard; Scuvera, Giulietta; Manoukian, Siranoush; Radice, Paolo; Ottini, Laura; Montagna, Marco; Agata, Simona; Maugard, Christine; Simard, Jacques; Soucy, Penny; Berger, Andreas; Fink-Retter, Anneliese; Singer, Christian F; Rappaport, Christine; Geschwantler-Kaulich, Daphne; Tea, Muy-Kheng; Pfeiler, Georg; John, Esther M; Miron, Alex; Neuhausen, Susan L; Terry, Mary Beth; Chung, Wendy K; Daly, Mary B; Goldgar, David E; Janavicius, Ramunas; Dorfling, Cecilia M; van Rensburg, Elisabeth J; Fostira, Florentia; Konstantopoulou, Irene; Garber, Judy; Godwin, Andrew K; Olah, Edith; Narod, Steven A; Rennert, Gad; Paluch, Shani Shimon; Laitman, Yael; Friedman, Eitan; Liljegren, Annelie; Rantala, Johanna; Stenmark-Askmalm, Marie; Loman, Niklas; Imyanitov, Evgeny N; Hamann, Ute; Spurdle, Amanda B; Healey, Sue; Weitzel, Jeffrey N; Herzog, Josef; Margileth, David; Gorrini, Chiara; Esteller, Manel; Gómez, Antonio; Sayols, Sergi; Vidal, Enrique; Heyn, Holger; Stoppa-Lyonnet, Dominique; Léoné, Melanie; Barjhoux, Laure; Fassy-Colcombet, Marion; de Pauw, Antoine; Lasset, Christine; Ferrer, Sandra Fert; Castera, Laurent; Berthet, Pascaline; Cornelis, François; Bignon, Yves-Jean; Damiola, Francesca; Mazoyer, Sylvie; Sinilnikova, Olga M; Maxwell, Christopher A; Vijai, Joseph; Robson, Mark; Kauff, Noah; Corines, Marina J; Villano, Danylko; Cunningham, Julie; Lee, Adam; Lindor, Noralane; Lázaro, Conxi; Easton, Douglas F; Offit, Kenneth; Chenevix-Trench, Georgia; Couch, Fergus J; Antoniou, Antonis C; Pujana, Miguel Angel

    2015-01-01

    While interplay between BRCA1 and AURKA-RHAMM-TPX2-TUBG1 regulates mammary epithelial polarization, common genetic variation in HMMR (gene product RHAMM) may be associated with risk of breast cancer in BRCA1 mutation carriers. Following on these observations, we further assessed the link between the AURKA-HMMR-TPX2-TUBG1 functional module and risk of breast cancer in BRCA1 or BRCA2 mutation carriers. Forty-one single nucleotide polymorphisms (SNPs) were genotyped in 15,252 BRCA1 and 8,211 BRCA2 mutation carriers and subsequently analyzed using a retrospective likelihood approach. The association of HMMR rs299290 with breast cancer risk in BRCA1 mutation carriers was confirmed: per-allele hazard ratio (HR) = 1.10, 95% confidence interval (CI) 1.04-1.15, p = 1.9 x 10(-4) (false discovery rate (FDR)-adjusted p = 0.043). Variation in CSTF1, located next to AURKA, was also found to be associated with breast cancer risk in BRCA2 mutation carriers: rs2426618 per-allele HR = 1.10, 95% CI 1.03-1.16, p = 0.005 (FDR-adjusted p = 0.045). Assessment of pairwise interactions provided suggestions (FDR-adjusted pinteraction values > 0.05) for deviations from the multiplicative model for rs299290 and CSTF1 rs6064391, and rs299290 and TUBG1 rs11649877 in both BRCA1 and BRCA2 mutation carriers. Following these suggestions, the expression of HMMR and AURKA or TUBG1 in sporadic breast tumors was found to potentially interact, influencing patients' survival. Together, the results of this study support the hypothesis of a causative link between altered function of AURKA-HMMR-TPX2-TUBG1 and breast carcinogenesis in BRCA1/2 mutation carriers. PMID:25830658

  10. Effect of the BRCA1-SIRT1-EGFR axis on cisplatin sensitivity in ovarian cancer

    PubMed Central

    Li, Da; Wu, Qi-Jun; Bi, Fang-Fang; Chen, Si-Lei; Zhou, Yi-Ming; Zhao, Yue; Yang, Qing

    2016-01-01

    There is accumulating evidence that breast cancer 1 (BRCA1), sirtuin 1 (SIRT1), and epidermal growth factor receptor (EGFR) help to modulate cisplatin cytotoxicity. The role of dynamic crosstalk among BRCA1, SIRT1, and EGFR in cisplatin sensitivity remains largely unknown. We found that BRCA1, SIRT1, and EGFR levels were increased in cisplatin-resistant ovarian cancers compared with those in cisplatin-sensitive ovarian cancers. Hypomethylation in the BRCA1 promoter was associated with BRCA1 activation, significantly elevated SIRT1 levels, decreased nicotinamide adenine dinucleotide (NAD)-mediated SIRT1 activity, and decreased EGFR levels. Treatment with 5 and 10 μg/ml cisplatin induced a gradual increase in BRCA1 and SIRT1 levels and a gradual decrease in NAD levels and NAD-mediated SIRT1 activity, whereas EGFR levels were increased or decreased by treatment with 5 or 10 μg/ml cisplatin, respectively. The overexpression of SIRT1 or the enhancement of SIRT1 activity synergistically enhanced the BRCA1-mediated effects on EGFR transcription. In contrast, the knockdown of SIRT1 or the inhibition of SIRT1 activity inhibited the BRCA1-mediated effects on EGFR transcription. BRCA1 regulates EGFR through a BRCA1-mediated balance between SIRT1 expression and activity. Those results improve our understanding of the basic molecular mechanism underlying BRCA1-related cisplatin resistance in ovarian cancer. PMID:27186285

  11. Altered Proliferation and Differentiation Properties of Primary Mammary Epithelial Cells from BRCA1 Mutation Carriers

    PubMed Central

    Burga, Laura N.; Tung, Nadine M.; Troyan, Susan L.; Bostina, Mihnea; Konstantinopoulos, Panagiotis A.; Fountzilas, Helena; Spentzos, Dimitrios; Miron, Alexander; Yassin, Yosuf A.; Lee, Bernard T.; Wulf, Gerburg M.

    2011-01-01

    Female BRCA1 mutation carriers have a nearly 80% probability of developing breast cancer during their life-time. We hypothesized that the breast epithelium at risk in BRCA1 mutation carriers harbors mammary epithelial cells (MEC) with altered proliferation and differentiation properties. Using a three-dimensional culture technique to grow MECs ex vivo, we found that the ability to form colonies, an indication of clonality, was restricted to the aldehyde dehydrogenase 1–positive fraction in MECs but not in HCC1937 BRCA1-mutant cancer cells. Primary MECs from BRCA1 mutation carriers (n = 9) had a 28% greater ability for clonal growth compared with normal controls (n= 6; P = 0.006), and their colonies were significantly larger. Colonies in controls and BRCA1 mutation carriers stained positive for BRCA1 by immunohistochemistry, and 79% of the examined single colonies from BRCA1 carriers retained heterozygosity for BRCA1 (ROH). Colonies from BRCA1 mutation carriers frequently showed high epidermal growth factor receptor (EGFR) expression (71% EGFR positive versus 44% in controls) and were negative for estrogen receptor (ERα; 32% ER negative, 44% mixed, 24% ER positive versus 90% ER positive in controls). Expression of CK14 and p63 were not significantly different. Microarray studies revealed that colonies from BRCA1-mutant PMECs anticipate expression profiles found in BRCA1-related tumors, and that the EGFR pathway is up-regulated. We conclude that BRCA1 haploin-sufficiency leads to an increased ability for clonal growth and proliferation in the PMECs of BRCA1 mutation carriers, possibly as a result of EGFR pathway activation. These altered growth and differentiation properties may render BRCA1-mutant PMECs vulnerable to transformation and predispose to the development of ER-negative, EGFR-positive breast cancers. PMID:19190334

  12. Parity and the risk of breast and ovarian cancer in BRCA1 and BRCA2 mutation carriers.

    PubMed

    Milne, Roger L; Osorio, Ana; Ramón y Cajal, Teresa; Baiget, Montserrat; Lasa, Adriana; Diaz-Rubio, Eduardo; de la Hoya, Miguel; Caldés, Trinidad; Teulé, Alex; Lázaro, Conxi; Blanco, Ignacio; Balmaña, Judith; Sánchez-Ollé, Gessamí; Vega, Ana; Blanco, Ana; Chirivella, Isabel; Esteban Cardeñosa, Eva; Durán, Mercedes; Velasco, Eladio; Martínez de Dueñas, Eduardo; Tejada, María-Isabel; Miramar, María-Dolores; Calvo, María-Teresa; Guillén-Ponce, Carmen; Salazar, Raquel; San Román, Carlos; Urioste, Miguel; Benítez, Javier

    2010-01-01

    Environmental or lifestyle factors are likely to explain part of the heterogeneity in breast and ovarian cancer risk among BRCA1 and BRCA2 mutation carriers. We assessed parity as a risk modifier in 515 and 503 Spanish female carriers of mutations in BRCA1 and BRCA2, respectively. Hazard ratios (HR) and their corresponding 95% confidence intervals (CI) were estimated using weighted Cox proportional hazards regression, adjusted for year of birth and study centre. The results for ever being parous and number of live-births were very similar for carriers of mutations in both genes. For all mutation carriers combined, the estimated HR associated with ever having had a live-birth was 0.74 (95% confidence interval [CI] = 0.55-1.01, P = 0.06), and that associated with each live-birth was 0.87 (95%CI = 0.77-0.98, P = 0.02). The latter association was observed only in women aged 40 and above (HR = 0.81, 95%CI = 0.70-0.94, P = 0.004 vs. HR = 0.99, 95%CI = 0.83-1.18, P = 0.9 for women under age 40), and this trend was highly consistently observed for carriers of mutations in each gene. There was no evidence of an association between breast cancer risk and age at first birth for parous BRCA1 or BRCA2 mutation carriers (P-trend >or= 0.3). The power to detect associations with ovarian cancer risk was much lower, especially for BRCA2 mutation carriers. Nevertheless, having a live-birth was associated with protection for BRCA1 mutation carriers (HR = 0.41, 95%CI = 0.18-0.94, P = 0.03), and a strong and consistent protective effect of age at first birth was observed for parous carriers of mutations in both genes (HR = 0.65, 95%CI = 0.52-0.83, P < 0.001). This is the third independent study to find that, as in the general population, parity appears to be associated with protection from breast cancer in women with mutations in BRCA1 and BRCA2. Parity appears to be protective for ovarian cancer in BRCA1 mutation carriers, but its role in BRCA2 mutation carriers remains unclear

  13. Prevalence of BRCA1 mutations among 403 women with triple-negative breast cancer: implications for genetic screening selection criteria: a Hellenic Cooperative Oncology Group Study.

    PubMed

    Fostira, Florentia; Tsitlaidou, Marianthi; Papadimitriou, Christos; Pertesi, Maroulio; Timotheadou, Eleni; Stavropoulou, Alexandra V; Glentis, Stavros; Bournakis, Evangelos; Bobos, Mattheos; Pectasides, Dimitrios; Papakostas, Pavlos; Pentheroudakis, George; Gogas, Helen; Skarlos, Pantelis; Samantas, Epaminontas; Bafaloukos, Dimitrios; Kosmidis, Paris A; Koutras, Angelos; Yannoukakos, Drakoulis; Konstantopoulou, Irene; Fountzilas, George

    2012-07-01

    In spite the close association of the triple-negative breast cancer immunophenotype with hereditary breast cancers and the BRCA1 pathway, there is a lack of population studies that determine the frequency of BRCA1 mutations among triple-negative breast cancer patients. To address this, we have screened a large sample of 403 women diagnosed with triple-negative invasive breast cancer, independently of their age or family history, for germline BRCA1 mutations. Median age at diagnosis was 50 years (range 20-83). The overall prevalence of triple-negative cases among the initial patient group with invasive breast cancer was 8%. BRCA1 was screened by direct DNA sequencing in all patients, including all exons where a mutation was previously found in the Greek population (exons 5, 11, 12, 16, 20, 21, 22, 23, 24-77% of the BRCA1 coding region), including diagnostic PCRs to detect the three Greek founder large genomic rearrangements. Sixty-five deleterious BRCA1 mutations were identified among the 403 triple-negative breast cancer patients (16%). Median age of onset for mutation carriers was 39 years. Among a total of 106 women with early-onset triple-negative breast cancer (<40 years), 38 (36%) had a BRCA1 mutation, while 27% of women with triple-negative breast cancer diagnosed before 50 years (56/208) had a BRCA1 mutation. A mutation was found in 48% (50/105) of the triple-negative breast cancer patients with family history of breast or ovarian cancer. It is noteworthy, however, that of the 65 carriers, 15 (23%) had no reported family history of related cancers. All but one of the carriers had grade III tumors (98%). These results indicate that women with early-onset triple-negative breast cancer, and ideally all triple-negative breast cancer patients, are candidates for BRCA1 genetic testing even in the absence of a family history of breast or ovarian cancer. PMID:22434525

  14. Role of BRCA1 and BRCA2 mutations in pancreatic cancer.

    PubMed

    Greer, Julia B; Whitcomb, David C

    2007-05-01

    Germline mutations in the tumour suppressor genes breast cancer antigen gene (BRCA)1 and BRCA2 have been proven to portend a drastically increased lifetime risk of breast and ovarian cancers in the individuals who carry them. A number of studies have shown that the third most common cancer associated with these mutations is pancreatic cancer. BRCA1/2 mutations are characterised by "allelic" or "phenotypic" heterogeneity, in that they demonstrate differing cancer expressivity between and within pedigrees that segregate their mutations. If the same mutation is present in all our cells, why do some families with a given mutation display predominantly breast cancer? Why do other lineages show a preponderance of ovarian cancer? And why would some families have members who develop mostly or exclusively pancreatic cancer--a cancer that occurs more commonly in men and that lacks consistent evidence for a hormonal basis to its aetiology--which is clearly the case for breast and ovarian cancer? The answer is that other modifying genetic and environmental factors must interact to preferentially incite carcinogenesis in one organ over another. We are just beginning to elucidate what these factors are. PMID:16973716

  15. Characterization of BRCA1 and BRCA2 splicing variants: a collaborative report by ENIGMA consortium members.

    PubMed

    Thomassen, Mads; Blanco, Ana; Montagna, Marco; Hansen, Thomas V O; Pedersen, Inge S; Gutiérrez-Enríquez, Sara; Menéndez, Mireia; Fachal, Laura; Santamariña, Marta; Steffensen, Ane Y; Jønson, Lars; Agata, Simona; Whiley, Phillip; Tognazzo, Silvia; Tornero, Eva; Jensen, Uffe B; Balmaña, Judith; Kruse, Torben A; Goldgar, David E; Lázaro, Conxi; Diez, Orland; Spurdle, Amanda B; Vega, Ana

    2012-04-01

    Mutations in BRCA1 and BRCA2 predispose carriers to early onset breast and ovarian cancer. A common problem in clinical genetic testing is interpretation of variants with unknown clinical significance. The Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA) consortium was initiated to evaluate and implement strategies to characterize the clinical significance of BRCA1 and BRCA2 variants. As an initial project of the ENIGMA Splicing Working Group, we report splicing and multifactorial likelihood analysis of 25 BRCA1 and BRCA2 variants from seven different laboratories. Splicing analysis was performed by reverse transcriptase PCR or mini gene assay, and sequencing to identify aberrant transcripts. The findings were compared to bioinformatic predictions using four programs. The posterior probability of pathogenicity was estimated using multifactorial likelihood analysis, including co-occurrence with a deleterious mutation, segregation and/or report of family history. Abnormal splicing patterns expected to lead to a non-functional protein were observed for 7 variants (BRCA1 c.441+2T>A, c.4184_4185+2del, c.4357+1G>A, c.4987-2A>G, c.5074G>C, BRCA2 c.316+5G>A, and c.8754+3G>C). Combined interpretation of splicing and multifactorial analysis classified an initiation codon variant (BRCA2 c.3G>A) as likely pathogenic, uncertain clinical significance for 7 variants, and indicated low clinical significance or unlikely pathogenicity for another 10 variants. Bioinformatic tools predicted disruption of consensus donor or acceptor sites with high sensitivity, but cryptic site usage was predicted with low specificity, supporting the value of RNA-based assays. The findings also provide further evidence that clinical RNA-based assays should be extended from analysis of invariant dinucleotides to routinely include all variants located within the donor and acceptor consensus splicing sites. Importantly, this study demonstrates the added value of

  16. No association of TGFB1 L10P genotypes and breast cancer risk in BRCA1 and BRCA2 mutation carriers: a multi-center cohort study

    PubMed Central

    Antoniou, Antonis C.; Llopis, Trinidad Caldes; Nevanlinna, Heli; Aittomäki, Kristiina; Simard, Jacques; Spurdle, Amanda B.; Couch, Fergus J.; Pereira, Lutecia H. Mateus; Greene, Mark H.; Andrulis, Irene L.; Pasche, Boris; Kaklamani, Virginia; Hamann, Ute; Szabo, Csilla; Peock, Susan; Cook, Margaret; Harrington, Patricia A.; Donaldson, Alan; Male, Allison M.; Gardiner, Carol Anne; Gregory, Helen; Side, Lucy E.; Robinson, Anne C.; Emmerson, Louise; Ellis, Ian; Peyrat, Jean-Philippe; Fournier, Joëlle; Vennin, Philippe; Adenis, Claude; Muller, Danièle; Fricker, Jean-Pierre; Longy, Michel; Sinilnikova, Olga M.; Stoppa-Lyonnet, Dominique; Schmutzler, Rita K.; Versmold, Beatrix; Engel, Christoph; Meindl, Alfons; Kast, Karin; Schaefer, Dieter; Froster, Ursula G.; Chenevix-Trench, Georgia; Easton, Douglas F.

    2008-01-01

    Background The transforming growth factor β-1 gene (TGFB1) is a plausible candidate for breast cancer susceptibility. The L10P variant of TGFB1 is associated with higher circulating levels and secretion of TGF-β, and recent large-scale studies suggest strongly that this variant is associated with breast cancer risk in the general population. Methods To evaluate whether TGFB1 L10P also modifies the risk of breast cancer in BRCA1 or BRCA2 mutation carriers, we undertook a multi-center study of 3,442 BRCA1 and 2,095 BRCA2 mutation carriers. Results We found no evidence of association between TGFB1 L10P and breast cancer risk in either BRCA1 or BRCA2 mutation carriers. The per-allele HR for the L10P variant was 1.01 (95%CI: 0.92–1.11) in BRCA1 carriers and 0.92 (95%CI: 0.81–1.04) in BRCA2 mutation carriers. Conclusions These results do not support the hypothesis that TGFB1 L10P genotypes modify the risk of breast cancer in BRCA1 or BRCA2 mutation carriers. PMID:18523885

  17. DNA Methylation Leads to DNA Repair Gene Down-Regulation and Trinucleotide Repeat Expansion in Patient-Derived Huntington Disease Cells.

    PubMed

    Mollica, Peter A; Reid, John A; Ogle, Roy C; Sachs, Patrick C; Bruno, Robert D

    2016-07-01

    Huntington disease (HD) is an autosomal dominantly inherited disease that exhibits genetic anticipation of affected progeny due to expansions of a trinucleotide repeat (TNR) region within the HTT gene. DNA repair machinery is a known effector of TNR instability; however, the specific defects in HD cells that lead to TNR expansion are unknown. We hypothesized that HD cells would be deficient in DNA repair gene expression. To test this hypothesis, we analyzed expression of select DNA repair genes involved in mismatch/loop-out repair (APEX1, BRCA1, RPA1, and RPA3) in patient-derived HD cells and found each was consistently down-regulated relative to wild-type samples taken from unaffected individuals in the same family. Rescue of DNA repair gene expression by 5-azacytidine treatment identified DNA methylation as a mediator of DNA repair gene expression deficiency. Bisulfite sequencing confirmed hypermethylation of the APEX1 promoter region in HD cells relative to control, as well as 5-azacytidine-induced hypomethylation. 5-Azacytidine treatments also resulted in stabilization of TNR expansion within the mutant HTT allele during long-term culture of HD cells. Our findings indicate that DNA methylation leads to DNA repair down-regulation and TNR instability in mitotically active HD cells and offer a proof of principle that epigenetic interventions can curb TNR expansions. PMID:27182645

  18. Low fouling label-free DNA sensor based on polyethylene glycols decorated with gold nanoparticles for the detection of breast cancer biomarkers.

    PubMed

    Wang, Wenting; Fan, Xiaojian; Xu, Shenghao; Davis, Jason J; Luo, Xiliang

    2015-09-15

    A label-free and low fouling biosensor based on functional polyethylene glycols selective for breast cancer susceptibility gene (BRCA1) is reported. Sensory interfaces were prepared through the modification of a glassy carbon electrode with highly cross-linked polyethylene glycol (PEG) film containing amine groups, followed by the self-assembly of gold nanoparticles and the immobilization of BRCA1 complementary single-strand 19-mer oligonucleotides. In the presence of a specific BRCA1 sequence capture and hybridization results in interfacial change sensitively monitored using electrochemical impedance spectroscopy. The combined utilization of a PEG polymer film and gold nanoparticle mixed interface enables very high levels of sensitivity and a highly effective assaying in patient samples. Assay linear range was from 50.0 fM to 1.0 nM, with a limit of detection of 1.72 fM. Furthermore, this label-free DNA sensor has been used for assaying BRCA1 in serum samples, showing its feasible potential for diagnostic applications in clinical analysis of breast cancer gene BRCA1. Foreseeable, this sensor made on this basis undoubtedly provide the most effective and sensitive detection for BRCA1. PMID:25884734

  19. BRCA1 and its phosphorylation involved in caffeine-inhibitable event upstream of G2 checkpoint

    NASA Astrophysics Data System (ADS)

    Li, Ning; Zhang, Hong; Wang, Yanling; Hao, Jifang

    2010-07-01

    Caffeine, which specifically inhibits ATM/ATR kinases, efficiently abrogates the ionizing radiation (IR)-induced G2 arrest and increases the sensitivity of various tumor cells to IR. Mechanisms for the effect of caffeine remain to be elucidated. As a target of ATM/ATR kinases, BRCA1 becomes activated and phosphorylated in response to IR. Thus, in this work, we investigated the possible role of BRCA1 in the effect of caffeine on G2 checkpoint and observed how BRCA1 phosphorylation was regulated in this process. For these purposes, the BRCA1 protein level and the phosphorylation states were analyzed by Western blotting by using an antibody against BRCA1 and phospho-specific antibodies against Ser-1423 and Ser-1524 residues in cells exposed to a combination of IR and caffeine. The results showed that caffeine down-regulated IR-induced BRCA1 expression and specifically abolished BRCA1 phosphorylation of Ser-1524, which was followed by an override of G2 arrest by caffeine. In addition, the ability of BRCA1 to transactivate p21 may be required for MCF-7 but not necessary for Hela response to caffeine. These data suggest that BRCA1 may be a potential target of caffeine. BRCA1 and its phosphorylation are most likely to be involved in the caffeine-inhibitable event upstream of G2 arrest.

  20. Prolactin inhibits a major tumor-suppressive function of wild type BRCA1.

    PubMed

    Chen, Kuan-Hui Ethan; Walker, Ameae M

    2016-06-01

    Even though mutations in the tumor suppressor, BRCA1, markedly increase the risk of breast and ovarian cancer, most breast and ovarian cancers express wild type BRCA1. An important question is therefore how the tumor-suppressive function of normal BRCA1 is overcome during development of most cancers. Because prolactin promotes these and other cancers, we investigated the hypothesis that prolactin interferes with the ability of BRCA1 to inhibit the cell cycle. Examining six different cancer cell lines with wild type BRCA1, and making use of both prolactin and the growth-inhibiting selective prolactin receptor modulator, S179D PRL, we demonstrate that prolactin activation of Stat5 results in the formation of a complex between phospho-Stat5 and BRCA1. Formation of this complex does not interfere with nuclear translocation or binding of BRCA1 to the p21 promoter, but does interfere with the ability of BRCA1 to transactivate the p21 promoter. Overexpression of a dominant-negative Stat5 in prolactin-stimulated cells resulted in increased p21 expression. We conclude that prolactin inhibits a major tumor-suppressive function of BRCA1 by interfering with BRCA1's upregulation of expression of the cell cycle inhibitor, p21. PMID:26970274

  1. BRCA1 as a nicotinamide adenine dinucleotide (NAD)-dependent metabolic switch in ovarian cancer

    PubMed Central

    Li, Da; Chen, Na-Na; Cao, Ji-Min; Sun, Wu-Ping; Zhou, Yi-Ming; Li, Chun-Yan; Wang, Xiu-Xia

    2014-01-01

    Both hereditary factors (e.g., BRCA1) and nicotinamide adenine dinucleotide (NAD)-dependent metabolic pathways are implicated in the initiation and progression of ovarian cancer. However, whether crosstalk exists between BRCA1 and NAD metabolism remains largely unknown. Here, we showed that: (i) BRCA1 inactivation events (mutation and promoter methylation) were accompanied by elevated levels of NAD; (ii) the knockdown or overexpression of BRCA1 was an effective way to induce an increase or decrease of nicotinamide phosphoribosyltransferase (Nampt)-related NAD synthesis, respectively; and (iii) BRCA1 expression patterns were inversely correlated with NAD levels in human ovarian cancer specimens. In addition, it is worth noting that: (i) NAD incubation induced increased levels of BRCA1 in a concentration-dependent manner; (ii) Nampt knockdown-mediated reduction in NAD levels was effective at inhibiting BRCA1 expression; and (iii) the overexpression of Nampt led to higher NAD levels and a subsequent increase in BRCA1 levels in primary ovarian cancer cells and A2780, HO-8910 and ES2 ovarian cancer cell lines. These results highlight a novel link between BRCA1 and NAD. Our findings imply that genetic (e.g., BRCA1 inactivation) and NAD-dependent metabolic pathways are jointly involved in the malignant progression of ovarian cancer. PMID:25486197

  2. Targeted Prostate Cancer Screening in BRCA1 and BRCA2 Mutation Carriers: Results from the Initial Screening Round of the IMPACT Study

    PubMed Central

    Bancroft, Elizabeth K.; Page, Elizabeth C.; Castro, Elena; Lilja, Hans; Vickers, Andrew; Sjoberg, Daniel; Assel, Melissa; Foster, Christopher S.; Mitchell, Gillian; Drew, Kate; Mæhle, Lovise; Axcrona, Karol; Evans, D. Gareth; Bulman, Barbara; Eccles, Diana; McBride, Donna; van Asperen, Christi; Vasen, Hans; Kiemeney, Lambertus A.; Ringelberg, Janneke; Cybulski, Cezary; Wokolorczyk, Dominika; Selkirk, Christina; Hulick, Peter J.; Bojesen, Anders; Skytte, Anne-Bine; Lam, Jimmy; Taylor, Louise; Oldenburg, Rogier; Cremers, Ruben; Verhaegh, Gerald; van Zelst-Stams, Wendy A.; Oosterwijk, Jan C.; Blanco, Ignacio; Salinas, Monica; Cook, Jackie; Rosario, Derek J.; Buys, Saundra; Conner, Tom; Ausems, Margreet G.; Ong, Kai-ren; Hoffman, Jonathan; Domchek, Susan; Powers, Jacquelyn; Teixeira, Manuel R.; Maia, Sofia; Foulkes, William D.; Taherian, Nassim; Ruijs, Marielle; den Enden, Apollonia T. Helderman-van; Izatt, Louise; Davidson, Rosemarie; Adank, Muriel A.; Walker, Lisa; Schmutzler, Rita; Tucker, Kathy; Kirk, Judy; Hodgson, Shirley; Harris, Marion; Douglas, Fiona; Lindeman, Geoffrey J.; Zgajnar, Janez; Tischkowitz, Marc; Clowes, Virginia E.; Susman, Rachel; Ramón y Cajal, Teresa; Patcher, Nicholas; Gadea, Neus; Spigelman, Allan; van Os, Theo; Liljegren, Annelie; Side, Lucy; Brewer, Carole; Brady, Angela F.; Donaldson, Alan; Stefansdottir, Vigdis; Friedman, Eitan; Chen-Shtoyerman, Rakefet; Amor, David J.; Copakova, Lucia; Barwell, Julian; Giri, Veda N.; Murthy, Vedang; Nicolai, Nicola; Teo, Soo-Hwang; Greenhalgh, Lynn; Strom, Sara; Henderson, Alex; McGrath, John; Gallagher, David; Aaronson, Neil; Ardern-Jones, Audrey; Bangma, Chris; Dearnaley, David; Costello, Philandra; Eyfjord, Jorunn; Rothwell, Jeanette; Falconer, Alison; Gronberg, Henrik; Hamdy, Freddie C.; Johannsson, Oskar; Khoo, Vincent; Kote-Jarai, Zsofia; Lubinski, Jan; Axcrona, Ulrika; Melia, Jane; McKinley, Joanne; Mitra, Anita V.; Moynihan, Clare; Rennert, Gad; Suri, Mohnish; Wilson, Penny; Killick, Emma; Moss, Sue; Eeles, Rosalind A.

    2014-01-01

    Background Men with germline breast cancer 1, early onset (BRCA1) or breast cancer 2, early onset (BRCA2) gene mutations have a higher risk of developing prostate cancer (PCa) than noncarriers. IMPACT (Identification of Men with a genetic predisposition to ProstAte Cancer: Targeted screening in BRCA1/2 mutation carriers and controls) is an international consortium of 62 centres in 20 countries evaluating the use of targeted PCa screening in men with BRCA1/2 mutations. Objective To report the first year's screening results for all men at enrolment in the study. Design, setting and participants We recruited men aged 40–69 yr with germline BRCA1/2 mutations and a control group of men who have tested negative for a pathogenic BRCA1 or BRCA2 mutation known to be present in their families. All men underwent prostate-specific antigen (PSA) testing at enrolment, and those men with PSA >3 ng/ml were offered prostate biopsy. Outcome measurements and statistical analysis PSA levels, PCa incidence, and tumour characteristics were evaluated. The Fisher exact test was used to compare the number of PCa cases among groups and the differences among disease types. Results and limitations We recruited 2481 men (791 BRCA1 carriers, 531 BRCA1 controls; 731 BRCA2 carriers, 428 BRCA2 controls). A total of 199 men (8%) presented with PSA >3.0 ng/ml, 162 biopsies were performed, and 59 PCas were diagnosed (18 BRCA1 carriers, 10 BRCA1 controls; 24 BRCA2 carriers, 7 BRCA2 controls); 66% of the tumours were classified as intermediate- or high-risk disease. The positive predictive value (PPV) for biopsy using a PSA threshold of 3.0 ng/ml in BRCA2 mutation carriers was 48%—double the PPV reported in population screening studies. A significant difference in detecting intermediate- or high-risk disease was observed in BRCA2 carriers. Ninety-five percent of the men were white, thus the results cannot be generalised to all ethnic groups. Conclusions The IMPACT screening network will be useful

  3. Plasma Proteomic Profiling in Hereditary Breast Cancer Reveals a BRCA1-Specific Signature: Diagnostic and Functional Implications

    PubMed Central

    Scumaci, Domenica; Tammè, Laura; Fiumara, Claudia Vincenza; Pappaianni, Giusi; Concolino, Antonio; Leone, Emanuela; Faniello, Maria Concetta; Quaresima, Barbara; Ricevuto, Enrico; Costanzo, Francesco Saverio; Cuda, Giovanni

    2015-01-01

    Background Breast cancer (BC) is a leading cause of death among women. Among the major risk factors, an important role is played by familial history of BC. Germ-line mutations in BRCA1/2 genes account for most of the hereditary breast and/or ovarian cancers. Gene expression profiling studies have disclosed specific molecular signatures for BRCA1/2-related breast tumors as compared to sporadic cases, which might help diagnosis and clinical follow-up. Even though, a clear hallmark of BRCA1/2-positive BC is still lacking. Many diseases are correlated with quantitative changes of proteins in body fluids. Plasma potentially carries important information whose knowledge could help to improve early disease detection, prognosis, and response to therapeutic treatments. The aim of this study was to develop a comprehensive approach finalized to improve the recovery of specific biomarkers from plasma samples of subjects affected by hereditary BC. Methods To perform this analysis, we used samples from patients belonging to highly homogeneous population previously reported. Depletion of high abundant plasma proteins, 2D gel analysis, liquid chromatography-tandem mass spectrometry (LC-MS/MS) and bioinformatics analysis were used into an integrated approach to investigate tumor-specific changes in the plasma proteome of BC patients and healthy family members sharing the same BRCA1 gene founder mutation (5083del19), previously reported by our group, with the aim to identify specific signatures. Results The comparative analysis of the experimental results led to the identification of gelsolin as the most promising biomarker. Conclusions Further analyses, performed using a panel of breast cancer cell lines, allowed us to further elucidate the signaling network that might modulate the expression of gelsolin in breast cancer. PMID:26061043

  4. Homologs of Breast Cancer Genes in Plants

    PubMed Central

    Trapp, Oliver; Seeliger, Katharina; Puchta, Holger

    2011-01-01

    Since the initial discovery of genes involved in hereditary breast cancer in humans, a vast wealth of information has been published. Breast cancer proteins were shown to work as tumor suppressors primarily through their involvement in DNA-damage repair. Surprisingly, homologs of these genes can be found in plant genomes, as well. Here, we want to give an overview of the identification and characterization of the biological roles of these proteins, in plants. In addition to the conservation of their function in DNA repair, new plant-specific characteristics have been revealed. BRCA1 is required for the efficient repair of double strand breaks (DSB) by homologous recombination in somatic cells of the model plant Arabidopsis thaliana. Bioinformatic analysis indicates that, whereas most homologs of key components of the different mammalian BRCA1 complexes are present in plant genomes, homologs of most factors involved in the recruitment of BRCA1 to the DSB cannot be identified. Thus, it is not clear at the moment whether differences exist between plants and animals at this important step. The most conserved region of BRCA1 and BARD1 homologs in plants is a PHD domain which is absent in mammals and which, in AtBARD1, might be involved in the transcriptional regulation of plant development. The presence of a plant-specific domain prompted us to reevaluate the current model for the evolution of BRCA1 homologs and to suggest a new hypothesis, in which we postulate that plant BRCA1 and BARD1 have one common predecessor that gained a PHD domain before duplication. Furthermore, work in Arabidopsis demonstrates that – as in animals – BRCA2 homologs are important for meiotic DNA recombination. Surprisingly, recent research has revealed that AtBRCA2 also has an important role in systemic acquired resistance. In Arabidopsis, BRCA2 is involved in the transcriptional regulation of pathogenesis-related (PR) genes via its interaction with the strand exchange protein RAD51. PMID

  5. The KL-VS sequence variant of Klotho and cancer risk in BRCA1 and BRCA2 mutation carriers

    PubMed Central

    Laitman, Yael; Kuchenbaecker, Karoline B.; Rantala, Johanna; Hogervorst, Frans; Peock, Susan; Godwin, Andrew K.; Arason, Adalgeir; Kirchhoff, Tomas; Offit, Kenneth; Isaacs, Claudine; Schmutzler, Rita K.; Wappenschmidt, Barbara; Nevanlinna, Heli; Chen, Xiaoqing; Chenevix-Trench, Georgia; Healey, Sue; Couch, Fergus; Peterlongo, Paolo; Radice, Paolo; Nathanson, Katherine L.; Caligo, Maria Adelaide; Neuhausen, Susan L.; Ganz, Patricia; Sinilnikova, Olga M.; McGuffog, Lesley; Easton, Douglas F.; Antoniou, Antonis C.; Wolf, Ido

    2012-01-01

    Klotho (KL) is a putative tumor suppressor gene in breast and pancreatic cancers located at chromosome 13q12. A functional sequence variant of Klotho (KL-VS) was previously reported to modify breast cancer risk in Jewish BRCA1 mutation carriers. The effect of this variant on breast and ovarian cancer risks in non-Jewish BRCA1/BRCA2 mutation carriers has not been reported. The KL-VS variant was genotyped in women of European ancestry carrying a BRCA mutation: 5,741 BRCA1 mutation carriers (2,997 with breast cancer, 705 with ovarian cancer, and 2,039 cancer free women) and 3,339 BRCA2 mutation carriers (1,846 with breast cancer, 207 with ovarian cancer, and 1,286 cancer free women) from 16 centers. Genotyping was accomplished using TaqMan® allelic discrimination or matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Data were analyzed within a retrospective cohort approach, stratified by country of origin and Ashkenazi Jewish origin. The per-allele hazard ratio (HR) for breast cancer was 1.02 (95% CI 0.93–1.12, P = 0.66) for BRCA1 mutation carriers and 0.92 (95% CI 0.82–1.04, P = 0.17) for BRCA2 mutation carriers. Results remained unaltered when analysis excluded prevalent breast cancer cases. Similarly, the per-allele HR for ovarian cancer was 1.01 (95% CI 0.84–1.20, P = 0.95) for BRCA1 mutation carriers and 0.9 (95% CI 0.66–1.22, P = 0.45) for BRCA2 mutation carriers. The risk did not change when carriers of the 6174delT mutation were excluded. There was a lack of association of the KL-VS Klotho variant with either breast or ovarian cancer risk in BRCA1 and BRCA2 mutation carriers. PMID:22212556

  6. Pregnancies, breast-feeding, and breast cancer risk in the International BRCA1/2 Carrier Cohort Study (IBCCS)

    PubMed Central

    Andrieu, Nadine; Goldgar, David E.; Easton, Douglas F.; Rookus, Matti; Brohet, Richard; Antoniou, Antonis C.; Peock, Susan; Evans, Gareth; Eccles, Diana; Douglas, Fiona; Noguès, Catherine; Gauthier-Villars, Marion; Chompret, Agnès; Van Leeuwen, Flora E.; Kluijt, Irma; Benitez, Javier; Arver, Brita; Olah, Edith; Chang-Claude, Jenny

    2006-01-01

    Background Multiparity, young age at first childbirth, and breastfeeding are associated with a reduced risk of breast cancer in the general population. The breast cancer predisposition gene, BRCA1, has been shown to have a central role in regulating normal cell differentiation. Reproductive factors may thus have an influence on breast cancer risk in BRCA1/2 carriers since mammary gland cells undergo cell division and differentiation during pregnancy. Methods We performed a retrospective cohort study of 1601 women who carried a mutation in BRCA1 or BRCA2. Information on reproductive factors was obtained from a questionnaire completed subsequent to genetic counseling. At censoring, 853 subjects were affected with breast cancer. Data analysis was performed using a weighted cohort approach. All statistical tests were two-sided. Results There was no statistically significant difference in the risk of breast cancer between parous and nulliparous women. Among parous women, an increasing number of full-term pregnancies was associated with a statistically significant decrease in the risk of breast cancer (Ptrend = .008); risk was reduced by 14% (95% confidence interval [CI]= 6% to 22%) for each additional birth. This association was the same for carriers of mutations in either BRCA1 or BRCA2 and was restricted to women older than 40 years. In BRCA2 mutation carriers, first childbirth at later ages was associated with a increased risk of breast cancer compared with first childbirth before age 20 years (20–24 years, HR = 2.33 [95% CI = 0.93 to 5.83], 25–29 years, HR = 2.68 [95% CI = 1.02 to 7.07], 30 or later, HR = 1.97 [95% CI = 0.67 to 5.81]), whereas in BRCA1 mutation carriers, first childbirth at age 30 or later was associated with a reduced risk compared with first childbirth before age 20 (HR = 0.58 [95% CI = 0.36 to 0.94]). Neither history of interrupted pregnancies nor history of breastfeeding was statistically significant associated with the risk of breast cancer

  7. BRCA1-2 diagnostic workflow from next-generation sequencing technologies to variant identification and final report.

    PubMed

    Pilato, Brunella; Pinto, Rosamaria; De Summa, Simona; Petriella, Daniela; Lacalamita, Rosanna; Danza, Katia; Paradiso, Angelo; Tommasi, Stefania

    2016-10-01

    The BRCA1-BRCA2 genes predispose to hereditary breast and ovarian cancer, and the germline and mutational status of these genes defines a target population that can benefit from PARP inhibitor treatments. To respond to the increasing number of BRCA1-BRCA2 tests, it is necessary to shift to high-throughput technologies that are reliable and less time consuming. Different methodological platforms are dedicated to this purpose with different approaches and algorithms for analysis. Our aim was to set up a cost-effective and low time-consuming BRCA1-BRCA2 mutation detection workflow using the Ion Torrent PGM technology. A retrospective cohort of 40 patients with familial breast/ovarian cancer previously tested by Sanger sequencing and a prospective cohort of 72 patients (validation set) were analyzed. The validation set included 64 patients affected by familial breast/ovarian cancer and eight sporadic ovarian cancer cases, who are potential candidates for PARPi treatments. A complete and standardized workflow easily usable and suitable in a certified laboratory has been proved and validated. This includes all steps from library preparation to the final report. The use of next-generation sequencing will be of benefit for patients enrolled in the genetic counseling process and, moreover, will enhance the process of selecting patients eligible for personalized treatments. © 2016 Wiley Periodicals, Inc. PMID:27225819

  8. Hereditary breast and ovarian cancer: new genes in confined pathways.

    PubMed

    Nielsen, Finn Cilius; van Overeem Hansen, Thomas; Sørensen, Claus Storgaard

    2016-09-01

    Genetic abnormalities in the DNA repair genes BRCA1 and BRCA2 predispose to hereditary breast and ovarian cancer (HBOC). However, only approximately 25% of cases of HBOC can be ascribed to BRCA1 and BRCA2 mutations. Recently, exome sequencing has uncovered substantial locus heterogeneity among affected families without BRCA1 or BRCA2 mutations. The new pathogenic variants are rare, posing challenges to estimation of risk attribution through patient cohorts. In this Review article, we examine HBOC genes, focusing on their role in genome maintenance, the possibilities for functional testing of putative causal variants and the clinical application of new HBOC genes in cancer risk management and treatment decision-making. PMID:27515922

  9. Recurrent gross mutations of the PTEN tumor suppressor gene in breast cancers with deficient DSB repair

    PubMed Central

    Saal, Lao H; Gruvberger-Saal, Sofia K; Persson, Camilla; Lövgren, Kristina; Jumppanen, Mervi; Staaf, Johan; Jönsson, Göran; Pires, Maira M; Maurer, Matthew; Holm, Karolina; Koujak, Susan; Subramaniyam, Shivakumar; Vallon-Christersson, Johan; Olsson, Haökan; Su, Tao; Memeo, Lorenzo; Ludwig, Thomas; Ethier, Stephen P; Krogh, Morten; Szabolcs, Matthias; Murty, Vundavalli VVS; Isola, Jorma; Hibshoosh, Hanina; Parsons, Ramon; Borg, Åke

    2010-01-01

    Basal-like breast cancer (BBC) is a subtype of breast cancer with poor prognosis1–3. Inherited mutations of BRCA1, a cancer susceptibility gene involved in double-strand DNA break (DSB) repair, lead to breast cancers that are nearly always of the BBC subtype3–5; however, the precise molecular lesions and oncogenic consequences of BRCA1 dysfunction are poorly understood. Here we show that heterozygous inactivation of the tumor suppressor gene Pten leads to the formation of basal-like mammary tumors in mice, and that loss of PTEN expression is significantly associated with the BBC subtype in human sporadic and BRCA1-associated hereditary breast cancers. In addition, we identify frequent gross PTEN mutations, involving intragenic chromosome breaks, inversions, deletions and micro copy number aberrations, specifically in BRCA1-deficient tumors. These data provide an example of a specific and recurrent oncogenic consequence of BRCA1-dependent dysfunction in DNA repair and provide insight into the pathogenesis of BBC with therapeutic implications. These findings also argue that obtaining an accurate census of genes mutated in cancer will require a systematic examination for gross gene rearrangements, particularly in tumors with deficient DSB repair. PMID:18066063

  10. Pre-test prediction models of BRCA1 or BRCA2 mutation in breast/ovarian families attending familial cancer clinics

    PubMed Central

    de la Hoya, M; Diez, O; Perez-Segura, P; Godino, J; Fernandez, J; Sanz, J; Alonso, C; Baiget, M; Diaz-Rubio, E; Caldes, T

    2003-01-01

    Objective: To test whether statistical models developed to calculate pre-test probability of being a BRCA1/2 carrier can differentiate better between the breast/ovarian families to be referred to the DNA test laboratory. Study design: A retrospective analysis was performed in 109 Spanish breast/ovarian families previously screened for germline mutations in both the BRCA1 and BRCA2 genes. Four easy to use logistic regression models originally developed in Spanish (HCSC model), Dutch (LUMC model), Finnish (HUCH model), and North American (U Penn model) families and one model based on empirical data of Frank 2002 were tested. A risk counsellor was asked to assign a subjective pre-test probability for each family. Sensitivity, specificity, negative and positive predictive values, and areas under receiver operator characteristics (ROC) curves were calculated in each case. Correlation between predicted probability and mutation prevalence was tested. All statistical tests were two sided. Results: Overall, the models performed well, improving the performances of a genetic counsellor. The median ROC curve area was 0.80 (range 0.77-0.82). At 100% sensitivity, the median specificity was 30% (range 25-33%). At 92% sensitivity, the median specificity was 42% (range 33.3-54.2%) and the median negative predictive value was 93% (range 89.7-98%). BRCA1 families tended to score higher risk than BRCA2 families in all models tested. Conclusions: All models increased the discrimination power of an experienced risk counsellor, suggesting that their use is valuable in the context of clinical counselling and genetic testing to optimise selection of patients for screening and allowing for more focused management. Models developed in different ethnic populations performed similarly well in a Spanish series of families, suggesting that models targeted to specific populations may not be necessary in all cases. Carrier probability as predicted by the models is consistent with actual prevalence

  11. BRCA1-linked marker in postmenopausal breast cancer families

    SciTech Connect

    Folsom, A.R.; Chen, P.L.; Sellers, T.A.

    1994-09-01

    A majority of breast and ovarian cancer families and half of the early-onset breast cancer families are linked to markers on 17q (BRCA1). While linkage has been demonstrated in families with premenopausal disease, few studies have tested these markers in families with postmenopausal breast cancer. In the Iowa Women`s Health Study, a population-based study of over 42,000 women, an association of waist-to-hip ratio (WHR) with the risk of postmenopausal breast cancer was found predominantly in women with a positive family history -- this interaction was associated with a 3.2-fold elevated risk. This effect was even more pronounced when the definition of family history included breast and ovarian cancer, known to be linked to 17q markers. We evaluated evidence for linkage with D17S579, a BRCA-1-linked marker, in 13 families in which the index case had postmenopausal breast cancer. Genotyping for alleles at D17S579 was performed on 84 blood samples. Linkage analysis assumed that the breast cancer trait had an autosomal dominant mode of inheritance with a penetrance of 80%. For the 13 families studied, the maximum lod score was 0.29 at a theta of 0.27. There was significant evidence against tight linkage of breast cancer with D17S579 (theta<0.4). Heterogeneity analysis suggested evidence for the presence of both linked and unlinked families. Partitioning informative families on WHR of the index case suggested heterogeneity. These data suggest that, in a subset of families identified by a postmenopausal breast cancer proband, risk of breast cancer may be mediated by BRCA1, with heterogeneity defined by WHR.

  12. Non-catalytic Roles for XPG with BRCA1 and BRCA2 in Homologous Recombination and Genome Stability.

    PubMed

    Trego, Kelly S; Groesser, Torsten; Davalos, Albert R; Parplys, Ann C; Zhao, Weixing; Nelson, Michael R; Hlaing, Ayesu; Shih, Brian; Rydberg, Björn; Pluth, Janice M; Tsai, Miaw-Sheue; Hoeijmakers, Jan H J; Sung, Patrick; Wiese, Claudia; Campisi, Judith; Cooper, Priscilla K

    2016-02-18

    XPG is a structure-specific endonuclease required for nucleotide excision repair, and incision-defective XPG mutations cause the skin cancer-prone syndrome xeroderma pigmentosum. Truncating mutations instead cause the neurodevelopmental progeroid disorder Cockayne syndrome, but little is known about how XPG loss results in this devastating disease. We identify XPG as a partner of BRCA1 and BRCA2 in maintaining genomic stability through homologous recombination (HRR). XPG depletion causes DNA double-strand breaks, chromosomal abnormalities, cell-cycle delays, defective HRR, inability to overcome replication fork stalling, and replication stress. XPG directly interacts with BRCA2, RAD51, and PALB2, and XPG depletion reduces their chromatin binding and subsequent RAD51 foci formation. Upstream in HRR, XPG interacts directly with BRCA1. Its depletion causes BRCA1 hyper-phosphorylation and persistent chromatin binding. These unexpected findings establish XPG as an HRR protein with important roles in genome stability and suggest how XPG defects produce severe clinical consequences including cancer and accelerated aging. PMID:26833090

  13. Gene Tied to Breast Cancer Raises Uterine Cancer Risk Too

    MedlinePlus

    ... news/fullstory_159652.html Gene Tied to Breast Cancer Raises Uterine Cancer Risk Too Women with BRCA1 may want to ... increased risk for a deadly form of uterine cancer, a new study finds. The BRCA1 gene mutation ...

  14. Identification of BRCA1 Deficiency Using Multi-Analyte Estimation of BRCA1 and Its Repressors in FFPE Tumor Samples from Patients with Triple Negative Breast Cancer

    PubMed Central

    Korlimarla, Aruna; Prabhu, Jyothi S.; Remacle, Jose; Rajarajan, Savitha; Raja, Uma; C. E., Anupama; Srinath, B. S.; Manjunath, Suraj; K. S., Gopinath; Correa, Marjorrie; M. S. N., Prasad; Sridhar, T. S.

    2016-01-01

    Purpose Apart from germ-line BRCA1-mutated breast cancers, a significant proportion of women with sporadic triple negative breast cancer (TNBC) sub-type are known to harbour varying levels of BRCA1-dysfuction. There is currently no established diagnostic method to identify these patients. Methods The analysis was performed on 183 primary breast cancer tumor specimens from our longitudinal case-series archived as formalin-fixed-paraffin-embedded (FFPE) blocks comprising 71 TNBCs and 112 Hormone receptor positive HER2 negative (HR+HER2-) tumors. Transcript levels of BRCA1 and two of its repressors ID4 and microRNA182 were determined by TaqMan quantitative PCR. BRCA1 protein was detected immunohistochemically with the MS110 antibody. Results The representation of BRCA1 and its repressor ID4 as a ratio led to improved separation of TNBCs from HR+HER2- compared to either measure by itself. We then dichotomised the continuous distribution of each of the three measurements (Protein, MIRNA and transcript:repressor ratio) into categories of deficient (0) and adequate (1). A composite BRCA1 Deficiency Score (BDS) was computed by the addition of the score for all three measures. Samples deficient on 2 or more measures were deemed to be BRCA1 deficient; and 40% of all TNBCs met this criterion. Conclusion We propose here a simple multi-level assay of BRCA1 deficiency using the BRCA1:ID4 ratio as a critical parameter that can be performed on FFPE samples in clinical laboratories by the estimation of only 3 bio-markers. The ease of testing will hopefully encourage adoption and clinical validation. PMID:27077368

  15. Triple-negative breast cancer: BRCAness and concordance of clinical features with BRCA1-mutation carriers

    PubMed Central

    Lips, E H; Mulder, L; Oonk, A; van der Kolk, L E; Hogervorst, F B L; Imholz, A L T; Wesseling, J; Rodenhuis, S; Nederlof, P M

    2013-01-01

    Background: BRCAness is defined as shared tumour characteristics between sporadic and BRCA-mutated cancers. However, how to exactly measure BRCAness and its frequency in breast cancer is not known. Assays to establish BRCAness would be extremely valuable for the clinical management of these tumours. We assessed BRCAness characteristics frequencies in a large cohort of triple-negative breast cancers (TNBCs). Methods: As a measure of BRCAness, we determined a specific BRCA1-like pattern by array Comparative Genomic Hybridisation (aCGH), and BRCA1 promoter methylation in 377 TNBCs, obtained from 3 different patient cohorts. Clinicopathological data were available for all tumours, BRCA1-germline mutation status and chemotherapy response data were available for a subset. Results: Of the tumours, 66–69% had a BRCA1-like aCGH profile and 27–37% showed BRCA1 promoter methylation. BRCA1-germline mutations and BRCA1 promoter methylation were mutually exclusive events (P=1 × 10−5). BRCAness was associated with younger age and grade 3 tumours. Chemotherapy response was significantly higher in BRCA1-mutated tumours, but not in tumours with BRCAness (63% (12 out of 19) vs 35% (18 out of 52) pathological complete remission rate, respectively). Conclusion: The majority of the TNBCs show BRCAness, and those tumours share clinicopathological characteristics with BRCA1-mutated tumours. A better characterisation of TNBC and the presence of BRCAness could have consequences for both hereditary breast cancer screening and the treatment of these tumours. PMID:23558900

  16. Anti-Müllerian hormone serum concentrations of women with germline BRCA1 or BRCA2 mutations

    PubMed Central

    Phillips, Kelly-Anne; Collins, Ian M.; Milne, Roger L.; McLachlan, Sue Anne; Friedlander, Michael; Hickey, Martha; Stern, Catharyn; Hopper, John L.; Fisher, Richard; Kannemeyer, Gordon; Picken, Sandra; Smith, Charmaine D.; Kelsey, Thomas W.; Anderson, Richard A.

    2016-01-01

    STUDY QUESTION Do women with BRCA1 or BRCA2 mutations have reduced ovarian reserve, as measured by circulating anti-Müllerian hormone (AMH) concentration? SUMMARY ANSWER Women with a germline mutation in BRCA1 have reduced ovarian reserve as measured by AMH. WHAT IS KNOWN ALREADY The DNA repair enzymes encoded by BRCA1 and BRCA2 are implicated in reproductive aging. Circulating AMH is a biomarker of ovarian reserve and hence reproductive lifespan. STUDY DESIGN, SIZE, DURATION This was a cross-sectional study of AMH concentrations of 693 women at the time of enrolment into the Kathleen Cuningham Foundation Consortium for research in the Familial Breast Cancer (kConFab) cohort study (recruitment from 19 August 1997 until 18 September 2012). AMH was measured on stored plasma samples between November 2014 and January 2015 using an electrochemiluminescence immunoassay platform. PARTICIPANTS/MATERIALS, SETTING, METHODS Eligible women were from families segregating BRCA1 or BRCA2 mutations and had known mutation status. Participants were aged 25–45 years, had no personal history of cancer, retained both ovaries and were not pregnant or breastfeeding at the time of plasma storage. Circulating AMH was measured for 172 carriers and 216 non-carriers from families carrying BRCA1 mutations, and 147 carriers and 158 non-carriers from families carrying BRCA2 mutations. Associations between plasma AMH concentration and carrier status were tested by linear regression, adjusted for age at plasma storage, oral contraceptive use, body mass index and cigarette smoking. MAIN RESULTS AND THE ROLE OF CHANCE Mean AMH concentration was negatively associated with age (P < 0.001). Mutation carriers were younger at blood draw than non-carriers (P ≤ 0.031). BRCA1 mutation carriers had, on average, 25% (95% CI: 5%–41%, P = 0.02) lower AMH concentrations than non-carriers and were more likely to have AMH concentrations in the lowest quartile for age (OR 1.84, 95% CI: 1.11–303, P = 0

  17. Distinct molecular pathogeneses of early-onset breast cancers in BRCA1 and BRCA2 mutation carriers: a population-based study.

    PubMed

    Armes, J E; Trute, L; White, D; Southey, M C; Hammet, F; Tesoriero, A; Hutchins, A M; Dite, G S; McCredie, M R; Giles, G G; Hopper, J L; Venter, D J

    1999-04-15

    Breast cancers arising in women with and without a germline mutation in the BRCA1 or BRCA2 gene display different histological features, which suggests unique mechanisms of molecular pathogenesis: We used a molecular pathological analysis to define the genetic abnormalities relevant to these specific pathogeneses. Tumor material was studied from 40 women with breast cancer diagnosed before 40 years of age, sampled from a population-based study and stratified by BRCA1 and BRCA2 germline mutation status. Cases were not selected for family history or ethnic origin, and none were known to be genetically related. Thus, germline mutation itself is likely to impact on the molecular pathogenesis of these tumors, with no substantial influence due to modifying genetic or environmental factors. Breast cancers occurring in BRCA1 mutation carriers had significantly higher levels of p53 expression, including the preinvasive (carcinoma in situ) stage of disease, compared with cancers occurring in BRCA2 mutation carriers or women with no detectable germline mutation. These cancers also had a higher proliferation rate as measured by Ki-67 antibody. Expression of the prognostic factors c-erbB-2, cyclin D1, and estrogen receptor was significantly less common in BRCA1 mutation carriers. Lower levels of cyclin D1 were also found in cancers from BRCA2 mutation carriers compared with non-mutation carriers. Direct p53 mutation analysis revealed mutations in 18% of all of the early-onset breast cancers within the study and included rare insertion and deletional mutations in cancers from BRCA1 mutation carriers. Our data indicate that a BRCA1 breast cancer phenotype may be recognized by an exceptionally high proliferation rate and early and frequent p53 overexpression but infrequent selection for overexpression of several other prognostic factor proteins known to be involved in breast oncogenesis. In contrast, breast cancers arising in BRCA2 mutation carriers have a more heterogeneous

  18. Interaction between Hormonal Receptor Status, Age and Survival in Patients with BRCA1/2 Germline Mutations: A Systematic Review and Meta-Regression

    PubMed Central

    Gonzalez, Laura Diez; Vera-Badillo, Francisco E.; Tibau, Ariadna; Goldstein, Robyn; Šeruga, Boštjan; Srikanthan, Amirrtha; Pandiella, Atanasio; Amir, Eitan; Ocana, Alberto

    2016-01-01

    Background Germline mutations in the BRCA1 and BRCA2 genes are the most frequent known hereditary causes of familial breast cancer. Little is known about the interaction of age at diagnosis, estrogen receptor (ER) and progesterone receptor (PgR) expression and outcomes in patients with BRCA1 or BRCA2 mutations. Methods A PubMed search identified publications exploring the association between BRCA mutations and clinical outcome. Hazard ratios (HR) for overall survival were extracted from multivariable analyses. Hazard ratios were weighted and pooled using generic inverse-variance and random-effect modeling. Meta-regression weighted by total study sample size was conducted to explore the influence of age, ER and PgR expression on the association between BRCA mutations and overall survival. Results A total of 16 studies comprising 10,180 patients were included in the analyses. BRCA mutations were not associated with worse overall survival (HR 1.06, 95% CI 0.84–1.34, p = 0.61). A similar finding was observed when evaluating the influence of BRCA1 and BRCA2 mutations on overall survival independently (BRCA1: HR 1.20, 95% CI 0.89–1.61, p = 0.24; BRCA2: HR 1.01, 95% CI 0.80–1.27, p = 0.95). Meta-regression identified an inverse association between ER expression and overall survival (β = -0.75, p = 0.02) in BRCA1 mutation carriers but no association with age or PgR expression (β = -0.45, p = 0.23 and β = 0.02, p = 0.97, respectively). No association was found for BRCA2 mutation status and age, ER, or PgR expression. Conclusion ER-expression appears to be an effect modifier in patients with BRCA1 mutations, but not among those with BRCA2 mutations. PMID:27149669

  19. "My funky genetics": BRCA1/2 mutation carriers' understanding of genetic inheritance and reproductive merger in the context of new reprogenetic technologies.

    PubMed

    Werner-Lin, Allison; Rubin, Lisa R; Doyle, Maya; Stern, Rikki; Savin, Katie; Hurley, Karen; Sagi, Michal

    2012-06-01

    Deleterious mutations in the BRCA1/BRCA2 genes elevate lifetime risk of breast and ovarian cancer. Each child of a mutation-positive parent has a 50% chance of inheriting it. Preimplantation genetic diagnosis (PGD) permits prospective parents to avoid the birth of a BRCA-mutation-positive child, introducing predictability into a process historically defined by chance. This investigation explored how BRCA1/2 mutation carriers understand genetic inheritance and consider a child's inheritance of a BRCA1/2 mutation, given the opportunities that exist to pursue PGD. Thirty-nine female and male BRCA1/2 mutation carriers of reproductive age were recruited from urban cancer and reproductive medical centers. Participants completed a standardized educational presentation on PGD and prenatal diagnosis, with pre- and posttest assessments. An interdisciplinary team of qualitative researchers analyzed data using grounded theory techniques. Participants expressed the belief that reproduction yields children with unique genetic strengths and challenges, including the BRCA1/2 mutation, family traits for which predictive tests do not exist, and hypothetical genetic risks. Participants expressed preference for biologically related children, yet stated their genetically "well" partner's lineage would be marred through reproductive merger, requiring the well partner to assume the burden of the BRCA1/2 mutation via their children. Participants expressed diverse views of genetically "well" partners' participation in family planning and risk management decisions. Pressure to use reprogenetic technology may grow as genetic susceptibility testing becomes more widely available. Work with individuals and couples across the disease spectrum must be attuned to the ways beliefs about genetic inheritance play into reproductive decision-making. PMID:22709328

  20. NGS-based BRCA1/2 mutation testing of high-grade serous ovarian cancer tissue: results and conclusions of the first international round robin trial.

    PubMed

    Endris, Volker; Stenzinger, Albrecht; Pfarr, Nicole; Penzel, Roland; Möbs, Markus; Lenze, Dido; Darb-Esfahani, Silvia; Hummel, Michael; Sabine-Merkelbach-Bruse; Jung, Andreas; Lehmann, Ulrich; Kreipe, Hans; Kirchner, Thomas; Büttner, Reinhard; Jochum, Wolfram; Höfler, Gerald; Dietel, Manfred; Weichert, Wilko; Schirmacher, Peter

    2016-06-01

    With the approval of olaparib as monotherapy treatment in platinum-sensitive, relapsed high-grade serous ovarian cancer by the European Medical Agency (EMA), comprehensive genotyping of BRCA1 and BRCA2 in tumor tissue has become a mandatory pre-therapeutic test. This requires significant advances in routine tumor test methodologies due to the large size of both genes and the lack of mutational hot spots. Classical focused screening approaches, like Sanger sequencing, do not allow for a sensitive, rapid, and economic analysis of tumor tissue. Next-generation sequencing (NGS) approaches employing targeted panels for BRCA1/2 to interrogate formalin-fixed and paraffin-embedded tumor samples from either surgical resection or biopsy specimens can overcome these limitations. Although focused NGS methods have been implemented by few centers in routine molecular diagnostics for the analysis of some druggable oncogenic mutations, the reliable diagnostic testing of the entire coding regions of BRCA1 and BRCA2 was a new challenge requiring extensive technological improvement and quality management. Here, we describe the implementation and results of the first round robin trial for BRCA1/2 mutation testing in tumor tissue that was conducted in central Europe on May 2015, shortly after the approval and prior to the official release of olaparib. The high success rate of 81 % (21/26 test centers) demonstrates that BRCA1/2 multicenter mutation testing is well feasible in FFPE tumor tissue, extending to other tumor entities beyond ovarian cancer. The high number of test centers passing the trial demonstrates the success of the concerted efforts by German, Swiss, and Austrian pathology centers to ensure quality-controlled NGS-based testing and proves the potential of this technology in routine molecular pathology. On the basis of our results, we provide recommendations for predictive testing of tumor tissue for BRCA1/2 to clinical decision making in ovarian cancer patients. PMID

  1. Risk-Reducing Salpingo-Oophorectomy for the Prevention of BRCA1- and BRCA2-Associated Breast and Gynecologic Cancer: A Multicenter, Prospective Study

    PubMed Central

    Kauff, Noah D.; Domchek, Susan M.; Friebel, Tara M.; Robson, Mark E.; Lee, Johanna; Garber, Judy E.; Isaacs, Claudine; Evans, D. Gareth; Lynch, Henry; Eeles, Rosalind A.; Neuhausen, Susan L.; Daly, Mary B.; Matloff, Ellen; Blum, Joanne L.; Sabbatini, Paul; Barakat, Richard R.; Hudis, Clifford; Norton, Larry; Offit, Kenneth; Rebbeck, Timothy R.

    2011-01-01

    Purpose Risk-reducing salpingo-oophorectomy (RRSO) has been widely adopted as a key component of breast and gynecologic cancer risk-reduction for women with BRCA1 and BRCA2 mutations. Despite 17% to 39% of all BRCA mutation carriers having a mutation in BRCA2, no prospective study to date has evaluated the efficacy of RRSO for the prevention of breast and BRCA-associated gynecologic (ovarian, fallopian tube or primary peritoneal) cancer when BRCA2 mutation carriers are analyzed separately from BRCA1 mutation carriers. Patients and Methods A total of 1,079 women 30 years of age and older with ovaries in situ and a deleterious BRCA1 or BRCA2 mutation were enrolled onto prospective follow-up studies at one of 11 centers from November 1, 1994 to December 1, 2004. Women self-selected RRSO or observation. Follow-up information through November 30, 2005, was collected by questionnaire and medical record review. The effect of RRSO on time to diagnosis of breast or BRCA-associated gynecologic cancer was analyzed using a Cox proportional-hazards model. Results During 3-year follow-up, RRSO was associated with an 85% reduction in BRCA1-associated gynecologic cancer risk (hazard ratio [HR] = 0.15; 95% CI, 0.04 to 0.56) and a 72% reduction in BRCA2-associated breast cancer risk (HR = 0.28; 95% CI, 0.08 to 0.92). While protection against BRCA1-associated breast cancer (HR = 0.61; 95% CI, 0.30 to 1.22) and BRCA2-associated gynecologic cancer (HR = 0.00; 95% CI, not estimable) was suggested, neither effect reached statistical significance. Conclusion The protection conferred by RRSO against breast and gynecologic cancers may differ between carriers of BRCA1 and BRCA2 mutations. Further studies evaluating the efficacy of risk-reduction strategies in BRCA mutation carriers should stratify by the specific gene mutated. PMID:18268356

  2. Molecular Mechanism Linking BRCA1 Dysfunction to High Grade Serous Epithelial Ovarian Cancers with Peritoneal Permeability and Ascites

    PubMed Central

    Desai, A; Xu, J; Aysola, K; Akinbobuyi, O; White, M; Reddy, VE; Okoli, J; Clark, C; Partridge, EE; Childs, Ed; Beech, DJ; Rice, MV; Reddy, ESP; Rao, VN

    2015-01-01

    Ovarian cancer constitutes the second most common gynecological cancer with a five-year survival rate of 40%. Among the various histotypes associated with hereditary ovarian cancer, high-grade serous epithelial ovarian carcinoma (HGSEOC) is the most predominant and women with inherited mutations in BRCA1 have a lifetime risk of 40–60%. HGSEOC is a challenge for clinical oncologists, due to late presentation of patient, diagnosis and high rate of relapse. Ovarian tumors have a wide range of clinical presentations including development of ascites as a result of deregulated endothelial function thereby causing increased vascular permeability of peritoneal vessels. The molecular mechanisms remain elusive. Studies have shown that fallopian tube cancers develop in women with BRCA1 gene mutations more often than previously suspected. Recent studies suggest that many primary peritoneal cancers and some high-grade serous epithelial ovarian carcinomas actually start in the fallopian tubes. In this article we have addressed the molecular pathway of a recently identified potential biomarker Ubc9 whose deregulated expression due to BRCA1 dysfunction can result in HGSEOC with peritoneal permeability and formation of ascites. We also discuss the role of downstream targets Caveolin-1 and Vascular Endothelial Growth Factor (VEGF) in the pathogenesis of ascites in ovarian carcinomas. Finally we hypothesize a signaling axis between Ubc9 over expression, loss of Caveolin-1 and induction of VEGF in BRCA1 mutant HGSEOC cells. We suggest that Ubc9-mediated stimulation of VEGF as a novel mechanism underlying ovarian cancer aggressiveness and ascites formation. Agents that target Ubc9 and VEGF signaling may represent a novel therapeutic strategy to impede peritoneal growth and spread of HGSEOC. PMID:26665166

  3. Knockdown of COUP-TFII inhibits cell proliferation and induces apoptosis through upregulating BRCA1 in renal cell carcinoma cells.

    PubMed

    Zheng, Jia; Qin, Weijun; Jiao, Dian; Ren, Jing; Wei, Ming; Shi, Shengjia; Xi, Wenjin; Wang, He; Yang, An-Gang; Huan, Yi; Wen, Weihong

    2016-10-01

    COUP-TFII belongs to the nuclear receptor family, which is highly expressed in many kinds of tumors. Previous studies have shown that COUP-TFII can promote tumor progression through regulating tumor angiogenesis and cell proliferation and migration of certain cancer cells. However, the function of COUP-TFII in renal cell carcinoma (RCC) is not clear. Here, we showed that clinical RCC tumor tissues showed much higher COUP-TFII expression level than adjacent normal tissues. When COUP-TFII was knocked down in RCC 769-P and 786-O cells by siRNA or shRNA-expressing lentivirus, the cell proliferation was markedly inhibited, and apoptosis increased. Moreover, the tumor growth of COUP-TFII knockdown 769-P and 786-O xenografts in nude mice was also obviously inhibited. Using qRT-PCR and Western blot, we showed that the expression of the tumor suppressor gene BRCA1 was upregulated in COUP-TFII knockdown cells. Simultaneously knockdown of BRCA1 and COUP-TFII partially rescued the inhibited cell proliferation and increased apoptosis in COUP-TFII single knockdown cells. These results indicate that COUP-TFII may play an oncogenic role in RCC, and COUP-TFII may promote tumor progression through inhibiting BRCA1. PMID:27193872

  4. IDENTIFICATION OF THE PREVALENT BRCA1 AND BRCA2 MUTATIONS IN THE FEMALE POPULATION OF PUERTO RICO

    PubMed Central

    Dutil, Julie; Colon-Colon, Jose L.; Matta, Jaime L.; Sutphen, Rebecca; Echenique, Miguel

    2012-01-01

    Mutations in the breast cancer 1, early onset (BRCA1) and breast cancer 2 (BRCA2) genes are responsible for the majority of hereditary breast cancers. Knowledge of the incidence and prevalence of BRCA mutations in a specific population or ethnic group is necessary to provide accurate genetic counseling for breast cancer patients and their families. However, these data have not been gathered in the population of Puerto Rico. We conducted a retrospective study of female breast cancer patients undergoing genetic testing for BRCA mutations in the highest volume breast surgery practices in San Juan, Puerto Rico. Data collection includes 3-generation family cancer history and results from complete BRCA sequencing. A total of 6 different deleterious mutations were observed, including 1 mutation in BRCA1 and 5 mutations in BRCA2. Three recurrent mutations (BRCA1 del exon1–2, BRCA2 4150G>T, and BRCA2 6027del4) account for over 70% of all the BRCA mutations observed in this study population. This study examines for the first time the characteristics of hereditary breast cancer in Puerto Rico, and assesses the accuracy of existing genetic risk assessment tools in that population. This data is expected to contribute to providing accurate and efficient tools for the clinical management of hereditary breast cancer in Puerto Rico. PMID:22682623

  5. BRCA1 and p53 Tumor Suppressor Molecules in Alzheimer’s Disease

    PubMed Central

    Nakanishi, Atsuko; Minami, Akari; Kitagishi, Yasuko; Ogura, Yasunori; Matsuda, Satoru

    2015-01-01

    Tumor suppressor molecules play a pivotal role in regulating DNA repair, cell proliferation, and cell death, which are also important processes in the pathogenesis of Alzheimer’s disease. Alzheimer’s disease is the most common neurodegenerative disorder, however, the precise molecular events that control the death of neuronal cells are unclear. Recently, a fundamental role for tumor suppressor molecules in regulating neurons in Alzheimer’s disease was highlighted. Generally, onset of neurodegenerative diseases including Alzheimer’s disease may be delayed with use of dietary neuro-protective agents against oxidative stresses. Studies suggest that dietary antioxidants are also beneficial for brain health in reducing disease-risk and in slowing down disease-progression. We summarize research advances in dietary regulation for the treatment of Alzheimer’s disease with a focus on its modulatory roles in BRCA1 and p53 tumor suppressor expression, in support of further therapeutic research in this field. PMID:25636033

  6. High-throughput fluorescence polarization assay to identify small molecule inhibitors of BRCT domains of breast cancer gene 1.

    PubMed

    Lokesh, G L; Rachamallu, Aparna; Kumar, G D Kishore; Natarajan, Amarnath

    2006-05-01

    The C-terminus region of the 1863 residue early onset of breast cancer gene 1 (BRCA1) nuclear protein contains a tandem globular carboxy terminus domain termed BRCT. The BRCT repeats in BRCA1 are phosphoserine- and/or phosphothreonine-specific binding modules. The interaction of the BRCT(BRCA1) domains with phosphorylated BRCA1-associated carboxyl terminal helicase (BACH1) is cell cycle regulated and is essential for DNA damage-induced checkpoint control during the transition from the G(2) phase to the M phase of the cell cycle. Development of a competitive, homogeneous, high-throughput fluorescence polarization (FP) assay to identify small molecule inhibitors of BRCT(BRCA1)-BACH1 interaction is reported here. The FP assay was used for measuring binding affinities and inhibition constants of BACH1 peptides and small molecule inhibitors of BRCT(BRCA1) domains, respectively. A fluorescently labeled wild-type BACH1 decapeptide (BDP1) containing the critical phosphoserine, a phenylalanine at (P+3), and a GST-BRCT fusion protein were used to establish the FP assay. BDP1 has a dissociation constant (K(d)) of 1.58+/-0.01microM and a dynamic range (DeltamP) of 164.9+/-1.9. The assay tolerates 20% dimethyl sulfoxide, which enables screening poorly soluble compounds. Under optimized conditions, a Z' factor of 0.87 was achieved in a 384-well format for high-throughput screening. PMID:16500609

  7. Comprehensive BRCA1 and BRCA2 mutation analyses and review of French Canadian families with at least three cases of breast cancer.

    PubMed

    Cavallone, Luca; Arcand, Suzanna L; Maugard, Christine M; Nolet, Serge; Gaboury, Louis A; Mes-Masson, Anne-Marie; Ghadirian, Parviz; Provencher, Diane; Tonin, Patricia N

    2010-12-01

    Few studies have reported on the comprehensive BRCA1/2 mutation analyses of hereditary breast cancer (HBC) families of French Canadian descent. Here we report the investigation of 82 families with at least 3 cases of breast cancer evaluated for mutations by DNA sequencing and/or multiplex ligation-dependent probe amplification (MLPA) assay. DNA sequencing identified pathogenic mutations in 37 (45.1%) families, of which 70.2% were one of three recurring mutations (BRCA1:R1443X, BRCA2:8765delAG, and BRCA2:E1953X) frequently reported in this founder population; and variants of uncertain clinical significance in 7 (8.5%) families of which two harbored BRCA2:E3002K. MLPA analysis of the 38 DNA sequence-negative families did not reveal any large rearrangements in BRCA1/2. A phenotypic characterization of the cancer families based on pathogenic mutation status revealed that there were significantly fewer very young age at diagnosis breast cancer cases (<36 years) in mutation-negative families (5.9%, 9 of 153) than in BRCA1 (22.8%, 13 of 57; P = 0.0003) or BRCA2 (22.9%, 27 of 118; P < 1× 10E5) mutation-positive families. There were significantly more mutation-positive families (29 of 36, 80.6%) with a very young age of onset of breast cancer case than those that did not (8 of 39, 20.5%) (P < 10E6). The comprehensive mutation analysis of BRCA1/2 suggests that genomic rearrangements are unlikely to account for sequence-negative HBC families and affirms that the presence of a very young age of diagnosis of breast cancer is strongly predictive of mutation carrier status of French Canadian HBC families. PMID:20694749

  8. BRCA1 loss pre-existing in small subpopulations of prostate cancer is associated with advanced disease and metastatic spread to lymph nodes and peripheral blood

    SciTech Connect

    Bednarz, Natalia; Eltze, Elke; Semjonow, Axel; Rink, Michael; Andreas, Antje; Mulder, Lennart; Hannemann, Juliane; Fisch, Margit; Pantel, Klaus; Weier, Heinz-Ulrich G.; Bielawski, Krzysztof P.; Brandt, Burkhard

    2010-03-19

    A recent study concluded that serum prostate specific antigen (PSA)-based screening is beneficial for reducing the lethality of PCa, but was also associated with a high risk of 'overdiagnosis'. Nevertheless, also PCa patients who suffered from organ confined tumors and had negative bone scans succumb to distant metastases after complete tumor resection. It is reasonable to assume that those tumors spread to other organs long before the overt manifestation of metastases. Our current results confirm that prostate tumors are highly heterogeneous. Even a small subpopulation of cells bearing BRCA1 losses can initiate PCa cell regional and distant dissemination indicating those patients which might be at high risk of metastasis. A preliminary study performed on a small cohort of multifocal prostate cancer (PCa) detected BRCA1 allelic imbalances (AI) among circulating tumor cells (CTCs). The present analysis was aimed to elucidate the biological and clinical role of BRCA1 losses on metastatic spread and tumor progression in prostate cancer patients. Experimental Design: To map molecular progression in PCa outgrowth we used FISH analysis of tissue microarrays (TMA), lymph node sections and CTC from peripheral blood. We found that 14% of 133 tested patients carried monoallelic BRCA1 loss in at least one tumor focus. Extended molecular analysis of chr17q revealed that this aberration was often a part of larger cytogenetic rearrangement involving chr17q21 accompanied by AI of the tumor suppressor gene PTEN and lack of the BRCA1 promoter methylation. The BRCA1 losses correlated with advanced T stage (p < 0.05), invasion to pelvic lymph nodes (LN, p < 0.05) as well as BR (p < 0.01). Their prevalence was twice as high within 62 LN metastases (LNMs) as in primary tumors (27%, p < 0.01). The analysis of 11 matched primary PCa-LNM pairs confirmed the suspected transmission of genetic abnormalities between those two sites. In 4 of 7 patients with metastatic disease, BRCA1 losses

  9. Common alleles at 6q25.1 and 1p11.2 are associated with breast cancer risk for BRCA1 and BRCA2 mutation carriers

    PubMed Central

    Antoniou, Antonis C; Kartsonaki, Christiana; Sinilnikova, Olga M.; Soucy, Penny; McGuffog, Lesley; Healey, Sue; Lee, Andrew; Peterlongo, Paolo; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Cattaneo, Elisa; Barile, Monica; Pensotti, Valeria; Pasini, Barbara; Dolcetti, Riccardo; Giannini, Giuseppe; Laura Putignano, Anna; Varesco, Liliana; Radice, Paolo; Mai, Phuong L.; Greene, Mark H.; Andrulis, Irene L.; Glendon, Gord; Ozcelik, Hilmi; Thomassen, Mads; Gerdes, Anne-Marie; Kruse, Torben A.; Birk Jensen, Uffe; Crüger, Dorthe G.; Caligo, Maria A.; Laitman, Yael; Milgrom, Roni; Kaufman, Bella; Paluch-Shimon, Shani; Friedman, Eitan; Loman, Niklas; Harbst, Katja; Lindblom, Annika; Arver, Brita; Ehrencrona, Hans; Melin, Beatrice; Nathanson, Katherine L.; Domchek, Susan M.; Rebbeck, Timothy; Jakubowska, Ania; Lubinski, Jan; Gronwald, Jacek; Huzarski, Tomasz; Byrski, Tomasz; Cybulski, Cezary; Gorski, Bohdan; Osorio, Ana; Ramón y Cajal, Teresa; Fostira, Florentia; Andrés, Raquel; Benitez, Javier; Hamann, Ute; Hogervorst, Frans B.; Rookus, Matti A.; Hooning, Maartje J.; Nelen, Marcel R.; van der Luijt, Rob B.; van Os, Theo A.M.; van Asperen, Christi J.; Devilee, Peter; Meijers-Heijboer, Hanne E.J.; Gómez Garcia, Encarna B.; Peock, Susan; Cook, Margaret; Frost, Debra; Platte, Radka; Leyland, Jean; Gareth Evans, D.; Lalloo, Fiona; Eeles, Ros; Izatt, Louise; Adlard, Julian; Davidson, Rosemarie; Eccles, Diana; Ong, Kai-ren; Cook, Jackie; Douglas, Fiona; Paterson, Joan; John Kennedy, M.; Miedzybrodzka, Zosia; Godwin, Andrew; Stoppa-Lyonnet, Dominique; Buecher, Bruno; Belotti, Muriel; Tirapo, Carole; Mazoyer, Sylvie; Barjhoux, Laure; Lasset, Christine; Leroux, Dominique; Faivre, Laurence; Bronner, Myriam; Prieur, Fabienne; Nogues, Catherine; Rouleau, Etienne; Pujol, Pascal; Coupier, Isabelle; Frénay, Marc; Hopper, John L.; Daly, Mary B.; Terry, Mary B.; John, Esther M.; Buys, Saundra S.; Yassin, Yosuf; Miron, Alexander; Goldgar, David; Singer, Christian F.; Tea, Muy-Kheng; Pfeiler, Georg; Catharina Dressler, Anne; Hansen, Thomas v.O.; Jønson, Lars; Ejlertsen, Bent; Bjork Barkardottir, Rosa; Kirchhoff, Tomas; Offit, Kenneth; Piedmonte, Marion; Rodriguez, Gustavo; Small, Laurie; Boggess, John; Blank, Stephanie; Basil, Jack; Azodi, Masoud; Ewart Toland, Amanda; Montagna, Marco; Tognazzo, Silvia; Agata, Simona; Imyanitov, Evgeny; Janavicius, Ramunas; Lazaro, Conxi; Blanco, Ignacio; Pharoah, Paul D.P.; Sucheston, Lara; Karlan, Beth Y.; Walsh, Christine S.; Olah, Edith; Bozsik, Aniko; Teo, Soo-Hwang; Seldon, Joyce L.; Beattie, Mary S.; van Rensburg, Elizabeth J.; Sluiter, Michelle D.; Diez, Orland; Schmutzler, Rita K.; Wappenschmidt, Barbara; Engel, Christoph; Meindl, Alfons; Ruehl, Ina; Varon-Mateeva, Raymonda; Kast, Karin; Deissler, Helmut; Niederacher, Dieter; Arnold, Norbert; Gadzicki, Dorothea; Schönbuchner, Ines; Caldes, Trinidad; de la Hoya, Miguel; Nevanlinna, Heli; Aittomäki, Kristiina; Dumont, Martine; Chiquette, Jocelyne; Tischkowitz, Marc; Chen, Xiaoqing; Beesley, Jonathan; Spurdle, Amanda B.; Neuhausen, Susan L.; Chun Ding, Yuan; Fredericksen, Zachary; Wang, Xianshu; Pankratz, Vernon S.; Couch, Fergus; Simard, Jacques; Easton, Douglas F.; Chenevix-Trench, Georgia

    2011-01-01

    Two single nucleotide polymorphisms (SNPs) at 6q25.1, near the ESR1 gene, have been implicated in the susceptibility to breast cancer for Asian (rs2046210) and European women (rs9397435). A genome-wide association study in Europeans identified two further breast cancer susceptibility variants: rs11249433 at 1p11.2 and rs999737 in RAD51L1 at 14q24.1. Although previously identified breast cancer susceptibility variants have been shown to be associated with breast cancer risk for BRCA1 and BRCA2 mutation carriers, the involvement of these SNPs to breast cancer susceptibility in mutation carriers is currently unknown. To address this, we genotyped these SNPs in BRCA1 and BRCA2 mutation carriers from 42 studies from the Consortium of Investigators of Modifiers of BRCA1/2. In the analysis of 14 123 BRCA1 and 8053 BRCA2 mutation carriers of European ancestry, the 6q25.1 SNPs (r2 = 0.14) were independently associated with the risk of breast cancer for BRCA1 mutation carriers [hazard ratio (HR) = 1.17, 95% confidence interval (CI): 1.11–1.23, P-trend = 4.5 × 10−9 for rs2046210; HR = 1.28, 95% CI: 1.18–1.40, P-trend = 1.3 × 10−8 for rs9397435], but only rs9397435 was associated with the risk for BRCA2 carriers (HR = 1.14, 95% CI: 1.01–1.28, P-trend = 0.031). SNP rs11249433 (1p11.2) was associated with the risk of breast cancer for BRCA2 mutation carriers (HR = 1.09, 95% CI: 1.02–1.17, P-trend = 0.015), but was not associated with breast cancer risk for BRCA1 mutation carriers (HR = 0.97, 95% CI: 0.92–1.02, P-trend = 0.20). SNP rs999737 (RAD51L1) was not associated with breast cancer risk for either BRCA1 or BRCA2 mutation carriers (P-trend = 0.27 and 0.30, respectively). The identification of SNPs at 6q25.1 associated with breast cancer risk for BRCA1 mutation carriers will lead to a better understanding of the biology of tumour development in these women. PMID:21593217

  10. Association of PHB 1630 C>T and MTHFR 677 C>T polymorphisms with breast and ovarian cancer risk in BRCA1/2 mutation carriers: results from a multicenter study

    PubMed Central

    Jakubowska, A; Rozkrut, D; Antoniou, A; Hamann, U; Scott, R J; McGuffog, L; Healy, S; Sinilnikova, O M; Rennert, G; Lejbkowicz, F; Flugelman, A; Andrulis, I L; Glendon, G; Ozcelik, H; Thomassen, M; Paligo, M; Aretini, P; Kantala, J; Aroer, B; von Wachenfeldt, A; Liljegren, A; Loman, N; Herbst, K; Kristoffersson, U; Rosenquist, R; Karlsson, P; Stenmark-Askmalm, M; Melin, B; Nathanson, K L; Domchek, S M; Byrski, T; Huzarski, T; Gronwald, J; Menkiszak, J; Cybulski, C; Serrano, P; Osorio, A; Cajal, T R; Tsitlaidou, M; Benítez, J; Gilbert, M; Rookus, M; Aalfs, C M; Kluijt, I; Boessenkool-Pape, J L; Meijers-Heijboer, H E J; Oosterwijk, J C; van Asperen, C J; Blok, M J; Nelen, M R; van den Ouweland, A M W; Seynaeve, C; van der Luijt, R B; Devilee, P; Easton, D F; Peock, S; Frost, D; Platte, R; Ellis, S D; Fineberg, E; Evans, D G; Lalloo, F; Eeles, R; Jacobs, C; Adlard, J; Davidson, R; Eccles, D; Cole, T; Cook, J; Godwin, A; Bove, B; Stoppa-Lyonnet, D; Caux-Moncoutier, V; Belotti, M; Tirapo, C; Mazoyer, S; Barjhoux, L; Boutry-Kryza, N; Pujol, P; Coupier, I; Peyrat, J-P; Vennin, P; Muller, D; Fricker, J-P; Venat-Bouvet, L; Johannsson, O Th; Isaacs, C; Schmutzler, R; Wappenschmidt, B; Meindl, A; Arnold, N; Varon-Mateeva, R; Niederacher, D; Sutter, C; Deissler, H; Preisler-Adams, S; Simard, J; Soucy, P; Durocher, F; Chenevix-Trench, G; Beesley, J; Chen, X; Rebbeck, T; Couch, F; Wang, X; Lindor, N; Fredericksen, Z; Pankratz, V S; Peterlongo, P; Bonanni, B; Fortuzzi, S; Peissel, B; Szabo, C; Mai, P L; Loud, J T; Lubinski, J

    2012-01-01

    Background: The variable penetrance of breast cancer in BRCA1/2 mutation carriers suggests that other genetic or environmental factors modify breast cancer risk. Two genes of special interest are prohibitin (PHB) and methylene-tetrahydrofolate reductase (MTHFR), both of which are important either directly or indirectly in maintaining genomic integrity. Methods: To evaluate the potential role of genetic variants within PHB and MTHFR in breast and ovarian cancer risk, 4102 BRCA1 and 2093 BRCA2 mutation carriers, and 6211 BRCA1 and 2902 BRCA2 carriers from the Consortium of Investigators of Modifiers of BRCA1 and BRCA2 (CIMBA) were genotyped for the PHB 1630 C>T (rs6917) polymorphism and the MTHFR 677 C>T (rs1801133) polymorphism, respectively. Results: There was no evidence of association between the PHB 1630 C>T and MTHFR 677 C>T polymorphisms with either disease for BRCA1 or BRCA2 mutation carriers when breast and ovarian cancer associations were evaluated separately. Analysis that evaluated associations for breast and ovarian cancer simultaneously showed some evidence that BRCA1 mutation carriers who had the rare homozygote genotype (TT) of the PHB 1630 C>T polymorphism were at increased risk of both breast and ovarian cancer (HR 1.50, 95%CI 1.10–2.04 and HR 2.16, 95%CI 1.24–3.76, respectively). However, there was no evidence of association under a multiplicative model for the effect of each minor allele. Conclusion: The PHB 1630TT genotype may modify breast and ovarian cancer risks in BRCA1 mutation carriers. This association need to be evaluated in larger series of BRCA1 mutation carriers. PMID:22669161

  11. Prevalence of the BRCA1 founder mutation c.5266dupin Brazilian individuals at-risk for the hereditary breast and ovarian cancer syndrome

    PubMed Central

    2011-01-01

    About 5-10% of breast and ovarian carcinomas are hereditary and most of these result from germline mutations in the BRCA1 and BRCA2 genes. In women of Ashkenazi Jewish ascendance, up to 30% of breast and ovarian carcinomas may be attributable to mutations in these genes, where 3 founder mutations, c.68_69del (185delAG) and c.5266dup (5382insC) in BRCA1 and c.5946del (6174delT) in BRCA2, are commonly encountered. It has been suggested by some authors that screening for founder mutations should be undertaken in all Brazilian women with breast cancer. Thus, the goal of this study was to determine the prevalence of three founder mutations, commonly identified in Ashkenazi individuals in a sample of non-Ashkenazi cancer-affected Brazilian women with clearly defined risk factors for hereditary breast and ovarian cancer (HBOC) syndrome. Among 137 unrelated Brazilian women from HBOC families, the BRCA1c.5266dup mutation was identified in seven individuals (5%). This prevalence is similar to that encountered in non-Ashkenazi HBOC families in other populations. However, among patients with bilateral breast cancer, the frequency of c.5266dup was significantly higher when compared to patients with unilateral breast tumors (12.1% vs 1.2%, p = 0.023). The BRCA1 c.68_69del and BRCA2 c.5946del mutations did not occur in this sample. We conclude that screening non-Ashkenazi breast cancer-affected women from the ethnically heterogeneous Brazilian populations for the BRCA1 c.68_69del and BRCA2 c.5946del is not justified, and that screening for BRCA1c.5266dup should be considered in high risk patients, given its prevalence as a single mutation. In high-risk patients, a negative screening result should always be followed by comprehensive BRCA gene testing. The finding of a significantly higher frequency of BRCA1 c.5266dup in women with bilateral breast cancer, as well as existence of other as yet unidentified founder mutations in this population, should be further assessed in a larger

  12. Large genomic rearrangements of BRCA1 and BRCA2 among patients referred for genetic analysis in Galicia (NW Spain): delimitation and mechanism of three novel BRCA1 rearrangements.

    PubMed

    Fachal, Laura; Blanco, Ana; Santamariña, Marta; Carracedo, Angel; Vega, Ana

    2014-01-01

    In the Iberian Peninsula, which includes mainly Spain and Portugal, large genomic rearrangements (LGRs) of BRCA1 and BRCA2 have respectively been found in up to 2.33% and 8.4% of families with hereditary breast and/or ovarian cancer (HBOC) that lack point mutations and small indels. In Galicia (Northwest Spain), the spectrum and frequency of BRCA1/BRCA2 point mutations differs from the rest of the Iberian populations. However, to date there are no Galician frequency reports of BRCA1/BRCA2 LGRs. Here we used multiplex ligation-dependent probe amplification (MLPA) to screen 651 Galician index cases (out of the 830 individuals referred for genetic analysis) without point mutations or small indels. We identified three different BRCA1 LGRs in four families. Two of them have been previously classified as pathogenic LGRs: the complete deletion of BRCA1 (identified in two unrelated families) and the deletion of exons 1 to 13. We also identified the duplication of exons 1 and 2 that is a LGR with unknown pathogenicity. Determination of the breakpoints of the BRCA1 LGRs using CNV/SNP arrays and sequencing identified them as NG_005905.2:g.70536_180359del, NG_005905.2:g.90012_97270dup, and NC_000017.10:g.41230935_41399840delinsAluSx1, respectively; previous observations of BRCA1 exon1-24del, exon1-2dup, and exon1-13del LGRs have not characterized them in such detail. All the BRCA1 LGRs arose from unequal homologous recombination events involving Alu elements. We also detected, by sequencing, one BRCA2 LGR, the Portuguese founder mutation c.156_157insAluYa5. The low frequency of BRCA1 LGRs within BRCA1 mutation carriers in Galicia (2.34%, 95% CI: 0.61-7.22) seems to differ from the Spanish population (9.93%, 95% CI: 6.76-14.27, P-value = 0.013) and from the rest of the Iberian population (9.76%, 95% CI: 6.69-13.94, P-value = 0.014). PMID:24686251

  13. Large Genomic Rearrangements of BRCA1 and BRCA2 among Patients Referred for Genetic Analysis in Galicia (NW Spain): Delimitation and Mechanism of Three Novel BRCA1 Rearrangements

    PubMed Central

    Fachal, Laura; Blanco, Ana; Santamariña, Marta; Carracedo, Angel; Vega, Ana

    2014-01-01

    In the Iberian Peninsula, which includes mainly Spain and Portugal, large genomic rearrangements (LGRs) of BRCA1 and BRCA2 have respectively been found in up to 2.33% and 8.4% of families with hereditary breast and/or ovarian cancer (HBOC) that lack point mutations and small indels. In Galicia (Northwest Spain), the spectrum and frequency of BRCA1/BRCA2 point mutations differs from the rest of the Iberian populations. However, to date there are no Galician frequency reports of BRCA1/BRCA2 LGRs. Here we used multiplex ligation-dependent probe amplification (MLPA) to screen 651 Galician index cases (out of the 830 individuals referred for genetic analysis) without point mutations or small indels. We identified three different BRCA1 LGRs in four families. Two of them have been previously classified as pathogenic LGRs: the complete deletion of BRCA1 (identified in two unrelated families) and the deletion of exons 1 to 13. We also identified the duplication of exons 1 and 2 that is a LGR with unknown pathogenicity. Determination of the breakpoints of the BRCA1 LGRs using CNV/SNP arrays and sequencing identified them as NG_005905.2:g.70536_180359del, NG_005905.2:g.90012_97270dup, and NC_000017.10:g.41230935_41399840delinsAluSx1, respectively; previous observations of BRCA1 exon1-24del, exon1-2dup, and exon1-13del LGRs have not characterized them in such detail. All the BRCA1 LGRs arose from unequal homologous recombination events involving Alu elements. We also detected, by sequencing, one BRCA2 LGR, the Portuguese founder mutation c.156_157insAluYa5. The low frequency of BRCA1 LGRs within BRCA1 mutation carriers in Galicia (2.34%, 95% CI: 0.61–7.22) seems to differ from the Spanish population (9.93%, 95% CI: 6.76–14.27, P-value = 0.013) and from the rest of the Iberian population (9.76%, 95% CI: 6.69–13.94, P-value = 0.014). PMID:24686251

  14. Pathology of breast and ovarian cancers among BRCA1 and BRCA2 mutation carriers: results from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA)

    PubMed Central

    Mavaddat, Nasim; Barrowdale, Daniel; Andrulis, Irene L.; Domchek, Susan M.; Eccles, Diana; Nevanlinna, Heli; Ramus, Susan J.; Spurdle, Amanda; Robson, Mark; Sherman, Mark; Mulligan, Anna Marie; Couch, Fergus J.; Engel, Christoph; McGuffog, Lesley; Healey, Sue; Sinilnikova, Olga M.; Southey, Melissa C.; Terry, Mary Beth; Goldgar, David; O’Malley, Frances; John, Esther M.; Janavicius, Ramunas; Tihomirova, Laima; Hansen, Thomas v O; Nielsen, Finn C.; Osorio, Ana; Stavropoulou, Alexandra; Benítez, Javier; Manoukian, Siranoush; Peissel, Bernard; Barile, Monica; Volorio, Sara; Pasini, Barbara; Dolcetti, Riccardo; Putignano, Anna Laura; Ottini, Laura; Radice, Paolo; Hamann, Ute; Rashid, Muhammad U.; Hogervorst, Frans B.; Kriege, Mieke; van der Luijt, Rob B.; Peock, Susan; Frost, Debra; Evans, D. Gareth; Brewer, Carole; Walker, Lisa; Rogers, Mark T.; Side, Lucy E.; Houghton, Catherine; Weaver, JoEllen; Godwin, Andrew K.; Schmutzler, Rita K.; Wappenschmidt, Barbara; Meindl, Alfons; Kast, Karin; Arnold, Norbert; Niederacher, Dieter; Sutter, Christian; Deissler, Helmut; Gadzicki, Doroteha; Preisler-Adams, Sabine; Varon-Mateeva, Raymonda; Schönbuchner, Ines; Gevensleben, Heidrun; Stoppa-Lyonnet, Dominique; Belotti, Muriel; Barjhoux, Laure; Isaacs, Claudine; Peshkin, Beth N.; Caldes, Trinidad; de al Hoya, Miguel; Cañadas, Carmen; Heikkinen, Tuomas; Heikkilä, Päivi; Aittomäki, Kristiina; Blanco, Ignacio; Lazaro, Conxi; Brunet, Joan; Agnarsson, Bjarni A.; Arason, Adalgeir; Barkardottir, Rosa B.; Dumont, Martine; Simard, Jacques; Montagna, Marco; Agata, Simona; D’Andrea, Emma; Yan, Max; Fox, Stephen; Rebbeck, Timothy R.; Rubinstein, Wendy; Tung, Nadine; Garber, Judy E.; Wang, Xianshu; Fredericksen, Zachary; Pankratz, Vernon S.; Lindor, Noralane M.; Szabo, Csilla; Offit, Kenneth; Sakr, Rita; Gaudet, Mia M.; Singer, Christian F.; Tea, Muy-Kheng; Rappaport, Christine; Mai, Phuong L.; Greene, Mark H.; Sokolenko, Anna; Imyanitov, Evgeny; Toland, Amanda Ewart; Senter, Leigha; Sweet, Kevin; Thomassen, Mads; Gerdes, Anne-Marie; Kruse, Torben; Caligo, Maria; Aretini, Paolo; Rantala, Johanna; von Wachenfeld, Anna; Henriksson, Karin; Steele, Linda; Neuhausen, Susan L.; Nussbaum, Bob; Beattie, Mary; Odunsi, Kunle; Sucheston, Lara; Gayther, Simon A; Nathanson, Kate; Gross, Jenny; Walsh, Christine; Karlan, Beth; Chenevix-Trench, Georgia; Easton, Douglas F.; Antoniou, Antonis C.

    2011-01-01

    Background Previous small studies found that BRCA1 and BRCA2 breast tumors differ in their pathology. Analysis of larger datasets of mutation carriers should allow further tumor characterization. Methods We used data from 4,325 BRCA1 and 2,568 BRCA2 mutation carriers to analyze the pathology of invasive breast, ovarian and contralateral breast cancers. Results There was strong evidence that the proportion of estrogen receptor (ER)-negative breast tumors decreased with age at diagnosis among BRCA1 (p-trend=1.2×10−5) but increased with age at diagnosis among BRCA2 carriers (p-trend=6.8×10−6). The proportion of triple negative tumors decreased with age at diagnosis in BRCA1 carriers but increased with age at diagnosis of BRCA2 carriers. In both BRCA1 and BRCA2 carriers, ER-negative tumors were of higher histological grade than ER-positive tumors (Grade 3 vs. Grade 1, p=1.2×10−13 for BRCA1 and p=0.001 for BRCA2). ER and progesterone receptor (PR) expression were independently associated with mutation carrier status (ER-positive odds ratio (OR) for BRCA2=9.4, 95%CI:7.0-12.6 and PR-positive OR=1.7, 95%CI:1.3-2.3, under joint analysis). Lobular tumors were more likely to be BRCA2-related (OR for BRCA2=3.3, 95%CI:2.4-4.4, p=4.4×10−14), and medullary tumors BRCA1-related (OR for BRCA2=0.25, 95%CI:0.18-0.35, p=2.3×10−15). ER-status of the first breast cancer was predictive of ER-status of asynchronous contralateral breast cancer (p=0.0004 for BRCA1; p=0.002 for BRCA2). There were no significant differences in ovarian cancer morphology between BRCA1 and BRCA2 carriers (serous:67%; mucinous:1%; endometriod:12%; clear-cell:2%). Conclusions/Impact Pathology characteristics of BRCA1 and BRCA2 tumors may be useful for improving risk prediction algorithms and informing clinical strategies for screening and prophylaxis. PMID:22144499

  15. Conserved Overlapping Gene Arrangement, Restricted Expression, and Biochemical Activities of DNA Polymerase ν (POLN)*

    PubMed Central

    Takata, Kei-ichi; Tomida, Junya; Reh, Shelley; Swanhart, Lisa M.; Takata, Minoru; Hukriede, Neil A.; Wood, Richard D.

    2015-01-01

    DNA polymerase ν (POLN) is one of 16 DNA polymerases encoded in vertebrate genomes. It is important to determine its gene expression patterns, biological roles, and biochemical activities. By quantitative analysis of mRNA expression, we found that POLN from the zebrafish Danio rerio is expressed predominantly in testis. POLN is not detectably expressed in zebrafish embryos or in mouse embryonic stem cells. Consistent with this, injection of POLN-specific morpholino antisense oligonucleotides did not interfere with zebrafish embryonic development. Analysis of transcripts revealed that vertebrate POLN has an unusual gene expression arrangement, sharing a first exon with HAUS3, the gene encoding augmin-like complex subunit 3. HAUS3 is broadly expressed in embryonic and adult tissues, in contrast to POLN. Differential expression of POLN and HAUS3 appears to arise by alternate splicing of transcripts in mammalian cells and zebrafish. When POLN was ectopically overexpressed in human cells, it specifically coimmunoprecipitated with the homologous recombination factors BRCA1 and FANCJ, but not with previously suggested interaction partners (HELQ and members of the Fanconi anemia core complex). Purified zebrafish POLN protein is capable of thymine glycol bypass and strand displacement, with activity dependent on a basic amino acid residue known to stabilize the primer-template. These properties are conserved with the human enzyme. Although the physiological function of pol ν remains to be clarified, this study uncovers distinctive aspects of its expression control and evolutionarily conserved properties of this DNA polymerase. PMID:26269593

  16. Lack of Correlation between Aberrant p16, RAR-β2, TIMP3, ERCC1, and BRCA1 Protein Expression and Promoter Methylation in Squamous Cell Carcinoma Accompanying Candida albicans-Induced Inflammation.

    PubMed

    Terayama, Yui; Matsuura, Tetsuro; Ozaki, Kiyokazu

    2016-01-01

    Hyperplastic candidiasis is characterized by thickening of the mucosal epithelia with Candida albicans infection with occasional progression to squamous cell carcinoma (SCC). C. albicans is a critical factor in tumor development; however, the oncogenic mechanism is unclear. We have previously produced an animal model for hyperplastic candidiasis in the rat forestomach. In the present study, we investigate whether impaired DNA methylation and associated protein expression of tumor suppressor and DNA repair genes are involved in the SCC carcinogenesis process using this hyperplastic candidiasis model. Promoter methylation and protein expression were analyzed by methylation specific PCR and immunohistochemical staining, respectively, of 5 areas in the forestomachs of alloxan-induced diabetic rats with hyperplastic candidiasis: normal squamous epithelia, squamous hyperplasia, squamous hyperplasia adjacent to SCC, squamous hyperplasia transitioning to SCC, and SCC. We observed nuclear p16 overexpression despite increases in p16 gene promoter methylation during the carcinogenic process. TIMP3 and RAR-β2 promoter methylation progressed until the precancerous stage but disappeared upon malignant transformation. In comparison, TIMP3 protein expression was suppressed during carcinogenesis and RAR-β2 expression was attenuated in the cytoplasm but enhanced in nuclei. ERCC1 and BRCA1 promoters were not methylated at any stage; however, their protein expression disappeared beginning at hyperplasia and nuclear protein re-expression in SCC was observed only for ERCC1. These results suggest that aberrant p16, RAR-β2, TIMP3, ERCC1, and BRCA1 expression might occur that is inconsistent with the respective gene promoter methylation status, and that this overexpression might serve to promote the inflammatory carcinogenesis caused by C. albicans infection. PMID:27410681