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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

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

    2016-06-12

    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.

  3. 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

  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. Factors forming the BRCA1-A complex orchestrate BRCA1 recruitment to the sites of DNA damage.

    PubMed

    Her, Joonyoung; Soo Lee, Nam; Kim, Yonghwan; Kim, Hongtae

    2016-07-01

    Sustaining genomic integrity is essential for preventing onset of cancers. Therefore, human cells evolve to have refined biological pathways to defend genetic materials from various genomic insults. DNA damage response and DNA repair pathways essential for genome maintenance are accomplished by cooperative executions of multiple factors including breast cancer type 1 susceptibility protein (BRCA1). BRCA1 is initially identified as an altered gene in the hereditary breast cancer patients. Since then, tremendous efforts to understand the functions of BRAC1 reveal that BRCA1 is found in distinct complexes, including BRCA1-A, BRCA1-B, BRCA1-C, and the BRCA1/PALB2/BRCA2 complex, and plays diverse roles in a context-dependent manner. Among the complexes, BRCA1-A is critical for BRCA1 recruitment to the sites of DNA damage. Factors comprising the BRCA1-A include RAP80, CCDC98/Abraxas, BRCC36, BRCC45, BARD1, BRCA1, and MERIT40, a RAP80-associated factor. In this review, we summarize recent findings of the factors that form the BRCA1-A complex.

  7. Factors forming the BRCA1-A complex orchestrate BRCA1 recruitment to the sites of DNA damage.

    PubMed

    Her, Joonyoung; Soo Lee, Nam; Kim, Yonghwan; Kim, Hongtae

    2016-07-01

    Sustaining genomic integrity is essential for preventing onset of cancers. Therefore, human cells evolve to have refined biological pathways to defend genetic materials from various genomic insults. DNA damage response and DNA repair pathways essential for genome maintenance are accomplished by cooperative executions of multiple factors including breast cancer type 1 susceptibility protein (BRCA1). BRCA1 is initially identified as an altered gene in the hereditary breast cancer patients. Since then, tremendous efforts to understand the functions of BRAC1 reveal that BRCA1 is found in distinct complexes, including BRCA1-A, BRCA1-B, BRCA1-C, and the BRCA1/PALB2/BRCA2 complex, and plays diverse roles in a context-dependent manner. Among the complexes, BRCA1-A is critical for BRCA1 recruitment to the sites of DNA damage. Factors comprising the BRCA1-A include RAP80, CCDC98/Abraxas, BRCC36, BRCC45, BARD1, BRCA1, and MERIT40, a RAP80-associated factor. In this review, we summarize recent findings of the factors that form the BRCA1-A complex. PMID:27325824

  8. 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

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

    PubMed

    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

  10. Isolation of tetranucleotide repeat polymorphisms flanking the BRCA1 gene

    SciTech Connect

    Bennett-Baker, P.E.; Kiousis, S.; King, S.E.

    1996-02-15

    This article reports on the isolation of tetranucleotide repeat polymorphisms which flank the BRCA1 gene on human chromosome 17. BRCA1 has been linked to both hereditary breast and ovarian cancer. Fifteen new short tandem repeat polymorphisms (STRPs) flanking the BRCA1 locus are reported. 18 refs., 2 figs., 1 tab.

  11. 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

  12. 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

  13. Hereditary truncating mutations of DNA repair and other genes in BRCA1/BRCA2/PALB2-negatively tested breast cancer patients.

    PubMed

    Lhota, F; Zemankova, P; Kleiblova, P; Soukupova, J; Vocka, M; Stranecky, V; Janatova, M; Hartmannova, H; Hodanova, K; Kmoch, S; Kleibl, Z

    2016-10-01

    Hereditary breast cancer comprises a minor but clinically meaningful breast cancer (BC) subgroup. Mutations in the major BC-susceptibility genes are important prognostic and predictive markers; however, their carriers represent only 25% of high-risk BC patients. To further characterize variants influencing BC risk, we performed SOLiD sequencing of 581 genes in 325 BC patients (negatively tested in previous BRCA1/BRCA2/PALB2 analyses). In 105 (32%) patients, we identified and confirmed 127 truncating variants (89 unique; nonsense, frameshift indels, and splice site), 19 patients harbored more than one truncation. Forty-six (36 unique) truncating variants in 25 DNA repair genes were found in 41 (12%) patients, including 16 variants in the Fanconi anemia (FA) genes. The most frequent variant in FA genes was c.1096_1099dupATTA in FANCL that also show a borderline association with increased BC risk in subsequent analysis of enlarged groups of BC patients and controls. Another 81 (53 unique) truncating variants were identified in 48 non-DNA repair genes in 74 patients (23%) including 16 patients carrying variants in genes coding proteins of estrogen metabolism/signaling. Our results highlight the importance of mutations in the FA genes' family, and indicate that estrogen metabolism genes may reveal a novel candidate genetic component for BC susceptibility. PMID:26822949

  14. 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

  15. Battle brewing over the BRCA1/2 gene patents.

    PubMed

    Agovic, Amina

    2010-01-01

    The revolutionary discovery of the DNA and the successful mapping of the human genome have allowed scientists worldwide to engage in an unprecedented research on the cutting-edge biomedical technology such as the genetic engineering (gene-splicing or recombinant DNA). However, as is often the case with modern bio-technologies, genes related innovation is heavily dependent on strong patent protection primarily due to high costs of research and commercialisation in this area. The aim of this paper is to provide a description of the District Court Ruling in the case of Association for Molecular Pathology et al v United States Patent and Trademark Office et al (ACLU v Myriad). In doing so, the article provides information on the relevant background at issues, including a brief introduction to general patentability requirements in relation to genes and the controversy surrounding the patentability of genetic material. The analysis of the complaint filed in the ACLU v Myriad case and the details of the District Court Ruling follows. The paper concludes with an outlook of the future legal actions involving Myriad's BRCA1/2 and the assessment of the potential impact that the BRCA1/2 District Court Ruling and subsequent appeal(s) may have on the American patent law.

  16. BRCA1 and CtIP suppress long tract gene conversion between sister chromatids

    PubMed Central

    Chandramouly, Gurushankar; Kwok, Amy; Huang, Bin; Willis, Nicholas A.; Xie, Anyong; Scully, Ralph

    2013-01-01

    BRCA1 controls early steps of the synthesis-dependent strand annealing (SDSA) pathway of homologous recombination, but has no known role following Rad51-mediated synapsis. Here we show that BRCA1 influences post-synaptic homologous recombination events, controlling the balance between short- (STGC) and long-tract gene conversion (LTGC) between sister chromatids. Brca1 mutant cells reveal a bias towards LTGC that is corrected by expression of wild type but not cancer-predisposing BRCA1 alleles. The LTGC bias is enhanced by depletion of CtIP but reversed by inhibition of 53BP1, implicating DNA end resection as a contributor to the STGC/LTGC balance. The impact of BRCA1/CtIP loss on the STGC/LTGC balance is abolished when the second (non-invading) end of the break is unable to support termination of STGC by homologous pairing (“annealing”). This suggests that BRCA1/CtIP-mediated processing of the second end of the break controls the annealing step that normally terminates SDSA, thereby suppressing the error-prone LTGC outcome. PMID:23994874

  17. A fluorescent multiplex-DGGE screening test for mutations in the BRCA1 gene.

    PubMed

    Kuperstein, Graciela; Jack, Elaine; Narod, Steven A

    2006-01-01

    Screening for mutations in the BRCA1 gene is challenging because of the wide spectrum of mutations found in this large gene. As the extensive exon 11 is commonly screened by the protein truncation test (PTT), here a fluorescent multiplex denaturing gradient gel electrophoresis (FMD) mutation screening technique was developed to test the remaining numerous small exons and splice sites of the gene. The method is based upon the use of an efficient multiplex polymerase chain reaction (PCR) amplification of the target regions, followed by denaturing gradient gel electrophoresis (DGGE) separation of the amplicon mixture, and the immediate achievement of results by wet gel scanning. The technique was applied to screen 16 samples with different BRCA1 sequence variants distributed over 12 exons. All variants were detected. In addition, 188 DNA samples from ovarian cancer patients were screened, identifying 22 new sequence variants (11.7% of the samples) and 243 common polymorphisms in the BRCA1 locus. Variants included 16 single nucleotide substitutions, 3 deletions of 2 nucleotides, 1 deletion of 4 nucleotides, and 2 insertions of 1 nucleotide. The FMD test provides an accurate, fast, nonradioactive and cost-efficient way to scan the BRCA1 gene with high sensitivity and an ease of result interpretation. This technique may prove to be a useful research tool for the detection of mutations and polymorphisms in the BRCA1 gene and for large-scale epidemiologic studies. PMID:16544996

  18. gDNA Enrichment by a Transposase-based Technology for NGS Analysis of the Whole Sequence of BRCA1, BRCA2, and 9 Genes Involved in DNA Damage Repair

    PubMed Central

    Chevrier, Sandy; Boidot, Romain

    2014-01-01

    The widespread use of Next Generation Sequencing has opened up new avenues for cancer research and diagnosis. NGS will bring huge amounts of new data on cancer, and especially cancer genetics. Current knowledge and future discoveries will make it necessary to study a huge number of genes that could be involved in a genetic predisposition to cancer. In this regard, we developed a Nextera design to study 11 complete genes involved in DNA damage repair. This protocol was developed to safely study 11 genes (ATM, BARD1, BRCA1, BRCA2, BRIP1, CHEK2, PALB2, RAD50, RAD51C, RAD80, and TP53) from promoter to 3'-UTR in 24 patients simultaneously. This protocol, based on transposase technology and gDNA enrichment, gives a great advantage in terms of time for the genetic diagnosis thanks to sample multiplexing. This protocol can be safely used with blood gDNA. PMID:25350069

  19. gDNA enrichment by a transposase-based technology for NGS analysis of the whole sequence of BRCA1, BRCA2, and 9 genes involved in DNA damage repair.

    PubMed

    Chevrier, Sandy; Boidot, Romain

    2014-10-06

    The widespread use of Next Generation Sequencing has opened up new avenues for cancer research and diagnosis. NGS will bring huge amounts of new data on cancer, and especially cancer genetics. Current knowledge and future discoveries will make it necessary to study a huge number of genes that could be involved in a genetic predisposition to cancer. In this regard, we developed a Nextera design to study 11 complete genes involved in DNA damage repair. This protocol was developed to safely study 11 genes (ATM, BARD1, BRCA1, BRCA2, BRIP1, CHEK2, PALB2, RAD50, RAD51C, RAD80, and TP53) from promoter to 3'-UTR in 24 patients simultaneously. This protocol, based on transposase technology and gDNA enrichment, gives a great advantage in terms of time for the genetic diagnosis thanks to sample multiplexing. This protocol can be safely used with blood gDNA.

  20. 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

  1. RAP80 Targets BRCA1 to Specific Ubiquitin Structures at DNA Damage Sites

    PubMed Central

    Sobhian, Bijan; Shao, Genze; Lilli, Dana R.; Culhane, Aedín C.; Moreau, Lisa A.; Xia, Bing; Livingston, David M.; Greenberg, Roger A.

    2009-01-01

    Mutations affecting the BRCT domains of the breast cancer–associated tumor suppressor BRCA1 disrupt the recruitment of this protein to DNA double-strand breaks (DSBs). The molecular structures at DSBs recognized by BRCA1 are presently unknown. We report the interaction of the BRCA1 BRCT domain with RAP80, a ubiquitin-binding protein. RAP80 targets a complex containing the BRCA1-BARD1 (BRCA1-associated ring domain protein 1) E3 ligase and the deubiquitinating enzyme (DUB) BRCC36 to MDC1-γH2AX–dependent lysine6- and lysine63-linked ubiquitin polymers at DSBs. These events are required for cell cycle checkpoint and repair responses to ionizing radiation, implicating ubiquitin chain recognition and turnover in the BRCA1-mediated repair of DSBs. PMID:17525341

  2. 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

  3. [Breast cancer genetics. BRCA1 and BRCA2: the main genes for disease predisposition].

    PubMed

    Ruiz-Flores, P; Calderón-Garcidueñas, A L; Barrera-Saldaña, H A

    2001-01-01

    Breast cancer is among the most common world cancers. In Mexico this neoplasm has been progressively increasing since 1990 and is expected to continue. The risk factors for this disease are age, some reproductive factors, ionizing radiation, contraceptives, obesity and high fat diets, among other factors. The main risk factor for BC is a positive family history. Several families, in which clustering but no mendelian inheritance exists, the BC is due probably to mutations in low penetrance genes and/or environmental factors. In families with autosomal dominant trait, the BRCA1 and BRCA2 genes are frequently mutated. These genes are the two main BC susceptibility genes. BRCA1 predispose to BC and ovarian cancer, while BRCA2 mutations predispose to BC in men and women. Both are long genes, tumor suppressors, functioning in a cell cycle dependent manner, and it is believed that both switch on the transcription of several genes, and participate in DNA repair. The mutations profile of these genes is known in developed countries, while in Latin America their search has just began. A multidisciplinary group most be responsible of the clinical management of patients with mutations in BRCA1 and BRCA2, and the risk assignment and Genetic counseling most be done carefully.

  4. 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

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

    PubMed

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

    2016-04-01

    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

  6. 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

  7. DNA repair capacity is impaired in healthy BRCA1 heterozygous mutation carriers.

    PubMed

    Vaclová, Tereza; Gómez-López, Gonzalo; Setién, Fernando; Bueno, José María García; Macías, José Antonio; Barroso, Alicia; Urioste, Miguel; Esteller, Manel; Benítez, Javier; Osorio, Ana

    2015-07-01

    BRCA1 germline mutations increase the lifetime risk of developing breast and ovarian cancers. However, taking into account the differences in disease manifestation among mutation carriers, it is probable that different BRCA1 mutations have distinct haploinsufficiency effects and lead to the formation of different phenotypes. Using lymphoblastoid cell lines derived from heterozygous BRCA1 mutation carriers and non-carriers, we investigated the haploinsufficiency effects of various mutation types using qPCR, immunofluorescence, and microarray technology. Lymphoblastoid cell lines carrying a truncating mutation showed significantly lower BRCA1 mRNA and protein levels and higher levels of gamma-H2AX than control cells or those harboring a missense mutation, indicating greater spontaneous DNA damage. Cells carrying either BRCA1 mutation type showed impaired RAD51 foci formation, suggesting defective repair in mutated cells. Moreover, compared to controls, cell lines carrying missense mutations displayed a more distinct expression profile than cells with truncating mutations, which is consistent with different mutations giving rise to distinct phenotypes. Alterations in the immune response pathway in cells harboring missense mutations point to possible mechanisms of breast cancer initiation in carriers of these mutations. Our findings offer insight into how various heterozygous mutations in BRCA1 could lead to impairment of BRCA1 function and provide strong evidence of haploinsufficiency in BRCA1 mutation carriers.

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

    PubMed

    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

  9. 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

  10. 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

  11. BRCA1-CtIP interaction in the repair of DNA double-strand breaks.

    PubMed

    Aparicio, Tomas; Gautier, Jean

    2016-07-01

    DNA termini at double-strand breaks are often chemically heterogeneous and require processing before initiation of repair. In a recent report, we demonstrated that CtIP and the MRE11-RAD50-NBS1 (MRN) nuclease complex cooperate with BRCA1 to specifically repair topoisomerase II-DNA adducted breaks. In contrast, BRCA1 is dispensable for repair of restriction endonuclease-generated double-strand breaks. PMID:27652321

  12. BRCA1-CtIP interaction in the repair of DNA double-strand breaks.

    PubMed

    Aparicio, Tomas; Gautier, Jean

    2016-07-01

    DNA termini at double-strand breaks are often chemically heterogeneous and require processing before initiation of repair. In a recent report, we demonstrated that CtIP and the MRE11-RAD50-NBS1 (MRN) nuclease complex cooperate with BRCA1 to specifically repair topoisomerase II-DNA adducted breaks. In contrast, BRCA1 is dispensable for repair of restriction endonuclease-generated double-strand breaks.

  13. 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

  14. 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

  15. Molecular insights into the OGG1 gene, a cancer risk modifier in BRCA1 and BRCA2 mutations carriers

    PubMed Central

    Benitez-Buelga, Carlos; Vaclová, Tereza; Ferreira, Sofia; Urioste, Miguel; Inglada-Perez, Lucia; Soberón, Nora; Blasco, Maria A.; Osorio, Ana; Benitez, Javier

    2016-01-01

    We have recently shown that rs2304277 variant in the OGG1 glycosidase gene of the Base Excision Repair pathway can increase ovarian cancer risk in BRCA1 mutation carriers. In the present study, we aimed to explore the role of this genetic variant on different genome instability hallmarks to explain its association with cancer risk. We have evaluated the effect of this polymorphism on OGG1 transcriptional regulation and its contribution to telomere shortening and DNA damage accumulation. For that, we have used a series of 89 BRCA1 and BRCA2 mutation carriers, 74 BRCAX cases, 60 non-carrier controls and 23 lymphoblastoid cell lines (LCL) derived from BRCA1 mutation carriers and non-carriers. We have identified that this SNP is associated to a significant OGG1 transcriptional down regulation independently of the BRCA mutational status and that the variant may exert a synergistic effect together with BRCA1 or BRCA2 mutations on DNA damage and telomere shortening. These results suggest that this variant, could be associated to a higher cancer risk in BRCA1 mutation carriers, due to an OGG1 transcriptional down regulation and its effect on genome instability. PMID:27015555

  16. 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

  17. Histone Ubiquitination Associates with BRCA1-Dependent DNA Damage Response▿ †

    PubMed Central

    Wu, Jiaxue; Huen, Michael S. Y.; Lu, Lin-Yu; Ye, Lin; Dou, Yali; Ljungman, Mats; Chen, Junjie; Yu, Xiaochun

    2009-01-01

    Histone ubiquitination participates in multiple cellular processes, including the DNA damage response. However, the molecular mechanisms involved are not clear. Here, we have identified that RAP80/UIMC1 (ubiquitin interaction motif containing 1), a functional partner of BRCA1, recognizes ubiquitinated histones H2A and H2B. The interaction between RAP80 and ubiquitinated histones H2A and H2B is increased following DNA damage. Since RAP80 facilitates BRCA1's translocation to DNA damage sites, our results indicate that ubiquitinated histones H2A and H2B could be upstream partners of the BRCA1/RAP80 complex in the DNA damage response. Moreover, we have found that RNF8 (ring finger protein 8), an E3 ubiquitin ligase, regulates ubiquitination of both histones H2A and H2B. In RNF8-deficient mouse embryo fibroblasts, ubiquitination of both histones H2A and H2B is dramatically reduced, which abolishes the DNA damage-induced BRCA1 and RAP80 accumulation at damage lesions on the chromatin. Taken together, our results suggest that ubiquitinated histones H2A and H2B may recruit the BRCA1 complex to DNA damage lesions on the chromatin. PMID:19015238

  18. 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.

  19. A case of familial breast cancer with double heterozygosity for BRCA1 and BRCA2 genes.

    PubMed

    Nomizu, Tadashi; Matsuzaki, Masami; Katagata, Naoto; Kobayashi, Yusuke; Sakuma, Takeshi; Monma, Tomoyuki; Saito, Motonobu; Watanabe, Fumiaki; Midorikawa, Shinichi; Yamaguchi, Yoshiko

    2015-09-01

    We report an extremely rare case of familial breast cancer with deleterious germline mutations in both BRCA1 and BRCA2 genes, of which, to date, no such case has been reported among Japanese breast/ovarian cancer patients. Genetic testing of the family members indicated that the same double heterozygosity for BRCA1 and BRCA2 genes was transmitted to the paternal cousin, and the same BRCA2 mutation to the younger sister with bilateral breast cancer, younger brother with stomach cancer, and proband's son and daughter without cancer. Immunohistochemical analysis of BRCA protein expression was performed using breast cancer tissues from the proband with double heterozygosity for BRCA1 and BRCA2 genes and from her sibling without BRCA1 mutation but with BRCA2 mutation. There was no staining of either BRCA in the proband and no staining of BRCA2 in the sibling.

  20. Selenium supplementation reduced oxidative DNA damage in adnexectomized BRCA1 mutations carriers.

    PubMed

    Dziaman, Tomasz; Huzarski, Tomasz; Gackowski, Daniel; Rozalski, Rafal; Siomek, Agnieszka; Szpila, Anna; Guz, Jolanta; Lubinski, Jan; Wasowicz, Wojciech; Roszkowski, Krzysztof; Olinski, Ryszard

    2009-11-01

    Some experimental evidence suggests that BRCA1 plays a role in repair of oxidative DNA damage. Selenium has anticancer properties that are linked with protection against oxidative stress. To assess whether supplementation of BRCA1 mutation carriers with selenium have a beneficial effect concerning oxidative stress/DNA damage in the present double-blinded placebo control study, we determined 8-oxodG level in cellular DNA and urinary excretion of 8-oxodG and 8-oxoGua in the mutation carriers. We found that 8-oxodG level in leukocytes DNA is significantly higher in BRCA1 mutation carriers. In the distinct subpopulation of BRCA1 mutation carriers without symptoms of cancer who underwent adnexectomy and were supplemented with selenium, the level of 8-oxodG in DNA decreased significantly in comparison with the subgroup without supplementation. Simultaneously in the same group, an increase of urinary 8-oxoGua, the product of base excision repair (hOGG1 glycosylase), was observed. Therefore, it is likely that the selenium supplementation of the patients is responsible for the increase of BER enzymes activities, which in turn may result in reduction of oxidative DNA damage. Importantly, in a double-blinded placebo control prospective study, it was shown that in the same patient groups, reduction in cancer incidents was observed. Altogether, these results suggest that BRCA1 deficiency contributes to 8-oxodG accumulation in cellular DNA, which in turn may be a factor responsible for cancer development in women with mutations, and that the risk to developed breast cancer in BRCA1 mutation carriers may be reduced in selenium-supplemented patients who underwent adnexectomy. PMID:19843683

  1. Single-step capture and sequencing of natural DNA for detection of BRCA1 mutations

    PubMed Central

    Thompson, John F.; Reifenberger, Jeffrey G.; Giladi, Eldar; Kerouac, Kristen; Gill, Jaime; Hansen, Erik; Kahvejian, Avak; Kapranov, Philipp; Knope, Travis; Lipson, Doron; Steinmann, Kathleen E.; Milos, Patrice M.

    2012-01-01

    Genetic testing for disease risk is an increasingly important component of medical care. However, testing can be expensive, which can lead to patients and physicians having limited access to the genetic information needed for medical decisions. To simplify DNA sample preparation and lower costs, we have developed a system in which any gene can be captured and sequenced directly from human genomic DNA without amplification, using no proteins or enzymes prior to sequencing. Extracted whole-genome DNA is acoustically sheared and loaded in a flow cell channel for single-molecule sequencing. Gene isolation, amplification, or ligation is not necessary. Accurate and low-cost detection of DNA sequence variants is demonstrated for the BRCA1 gene. Disease-causing mutations as well as common variants from well-characterized samples are identified. Single-molecule sequencing generates very reproducible coverage patterns, and these can be used to detect any size insertion or deletion directly, unlike PCR-based methods, which require additional assays. Because no gene isolation or amplification is required for sequencing, the exceptionally low costs of sample preparation and analysis could make genetic tests more accessible to those who wish to know their own disease susceptibility. Additionally, this approach has applications for sequencing integration sites for gene therapy vectors, transposons, retroviruses, and other mobile DNA elements in a more facile manner than possible with other methods. PMID:21765009

  2. Single-step capture and sequencing of natural DNA for detection of BRCA1 mutations.

    PubMed

    Thompson, John F; Reifenberger, Jeffrey G; Giladi, Eldar; Kerouac, Kristen; Gill, Jaime; Hansen, Erik; Kahvejian, Avak; Kapranov, Philipp; Knope, Travis; Lipson, Doron; Steinmann, Kathleen E; Milos, Patrice M

    2012-02-01

    Genetic testing for disease risk is an increasingly important component of medical care. However, testing can be expensive, which can lead to patients and physicians having limited access to the genetic information needed for medical decisions. To simplify DNA sample preparation and lower costs, we have developed a system in which any gene can be captured and sequenced directly from human genomic DNA without amplification, using no proteins or enzymes prior to sequencing. Extracted whole-genome DNA is acoustically sheared and loaded in a flow cell channel for single-molecule sequencing. Gene isolation, amplification, or ligation is not necessary. Accurate and low-cost detection of DNA sequence variants is demonstrated for the BRCA1 gene. Disease-causing mutations as well as common variants from well-characterized samples are identified. Single-molecule sequencing generates very reproducible coverage patterns, and these can be used to detect any size insertion or deletion directly, unlike PCR-based methods, which require additional assays. Because no gene isolation or amplification is required for sequencing, the exceptionally low costs of sample preparation and analysis could make genetic tests more accessible to those who wish to know their own disease susceptibility. Additionally, this approach has applications for sequencing integration sites for gene therapy vectors, transposons, retroviruses, and other mobile DNA elements in a more facile manner than possible with other methods.

  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. First BRCA1 and BRCA2 gene testing implemented in the health care system of Stockholm.

    PubMed

    Arver, B; Borg, A; Lindblom, A

    2001-01-01

    The aim of the study was to optimize the criteria for the BRCA1 and BRCA2 gene testing and to improve oncogenetic counseling in the Stockholm region. Screening for inherited breast cancer genes is laborious and a majority of tested samples turn out to be negative. The frequencies of mutations in the BRCA1 and BRCA2 genes differ across populations. Between 1997 and 2000, 160 families with breast and/or ovarian cancer were counseled and screened for mutations in the two genes. Twenty-five BRCA1 and two BRCA2 disease-causing mutations were found. Various factors associated with the probability of finding a BRCA1 mutation in the families were estimated. Age of onset in different generations and other malignancies were also studied. Families from our region in which both breast and ovarian cancer occur were likely to carry a BRCA1 mutation (34%). In breast-only cancer families, mutations were found only in those with very early onset. All breast- only cancer families with a mutation had at least one case of onset before 36 years of age and a young median age of onset (<43 years). Other malignancies than breast and ovarian cancers did not segregate in the BRCA1 families and surveillance for other malignancies is not needed, in general. Decreasing age of onset with successive generations was common and must be taken into account when surveillance options are considered. PMID:11336395

  5. Plasmonics nanoprobes: detection of single-nucleotide polymorphisms in the breast cancer BRCA1 gene.

    PubMed

    Wabuyele, Musundi B; Yan, Fei; Vo-Dinh, Tuan

    2010-09-01

    This paper describes the application of plasmonics-based nanoprobes that combine the modulation of the plasmonics effect to change the surface-enhanced Raman scattering (SERS) of a Raman label and the specificity of a DNA hairpin loop sequence to recognize and discriminate a variety of molecular target sequences. Hybridization with target DNA opens the hairpin and physically separates the Raman label from the metal nanoparticle thus reducing the plasmonics effect and quenching the SERS signal of the label. We have successfully demonstrated the specificity and selectivity of the nanoprobes in the detection of a single-nucleotide polymorphism (SNP) in the breast cancer BRCA1 gene in a homogenous solution at room temperature. In addition, the potential application of plasmonics nanoprobes for quantitative DNA diagnostic testing is discussed.

  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. BRCA1 is Required for Post-replication Repair After UV-induced DNA Damage

    PubMed Central

    Pathania, Shailja; Nguyen, Jenna; Hill, Sarah J.; Scully, Ralph; Feunteun, Jean; Livingston, David M.

    2011-01-01

    BRCA1 contributes to the response to UV irradiation. Utilizing its BRCT motifs, it is recruited during S/G2 to UV-damaged sites in a DNA replication-dependent, but nucleotide excision repair- independent manner. More specifically, at UV- stalled replication forks, it promotes photoproduct excision, suppression of translesion synthesis, and the localization and activation of replication factor C complex (RFC) subunits. The last function, in turn, triggers post-UV checkpoint activation and post- replicative repair. These BRCA1 functions differ from those required for DSBR. PMID:21963239

  8. 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

  9. 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.

  10. 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

  11. Localization of the VHR phosphatase gene and its analysis as a candidate for BRCA1

    SciTech Connect

    Kamb, A.; Rosenthal, J.; Tran, T.

    1994-09-01

    The VH1-related human protein (VHR) gene was localized to human chromosome 17q21 in a region thought to contain the BCRA1 locus, a locus that confers susceptibility to breast and ovarian cancer. VHR encodes a phosphatase with dual specificity for tyrosine and serine residues. Thus it is a plausible candidate for a tumor suppressor gene such as BRCA1. To test this possibility, the VHR coding sequence was screened in individuals with familial breast cancer and in sporadic breast tumor and breast cancer cell lines. No mutations were detected, suggesting that the VHR gene is not BRCA1. 18 refs., 3 figs.

  12. HP1 promotes tumor suppressor BRCA1 functions during the DNA damage response

    PubMed Central

    Lee, Young-Ho; Kuo, Ching-Ying; Stark, Jeremy M.; Shih, Hsiu-Ming; Ann, David K.

    2013-01-01

    The DNA damage response (DDR) involves both the control of DNA damage repair and signaling to cell cycle checkpoints. Therefore, unraveling the underlying mechanisms of the DDR is important for understanding tumor suppression and cellular resistance to clastogenic cancer therapeutics. Because the DDR is likely to be influenced by chromatin regulation at the sites of DNA damage, we investigated the role of heterochromatin protein 1 (HP1) during the DDR process. We monitored double-strand breaks (DSBs) using the γH2AX foci marker and found that depleting cells of HP1 caused genotoxic stress, a delay in the repair of DSBs and elevated levels of apoptosis after irradiation. Furthermore, we found that these defects in repair were associated with impaired BRCA1 function. Depleting HP1 reduced recruitment of BRCA1 to DSBs and caused defects in two BRCA1-mediated DDR events: (i) the homologous recombination repair pathway and (ii) the arrest of cell cycle at the G2/M checkpoint. In contrast, depleting HP1 from cells did not affect the non-homologous end-joining (NHEJ) pathway: instead it elevated the recruitment of the 53BP1 NHEJ factor to DSBs. Notably, all three subtypes of HP1 seemed to be almost equally important for these DDR functions. We suggest that the dynamic interaction of HP1 with chromatin and other DDR factors could determine DNA repair choice and cell fate after DNA damage. We also suggest that compromising HP1 expression could promote tumorigenesis by impairing the function of the BRCA1 tumor suppressor. PMID:23589625

  13. Novel mutations in the BRCA1 and BRCA2 genes in Iranian women with early-onset breast cancer

    PubMed Central

    Yassaee, Vahid R; Zeinali, Sirous; Harirchi, Iraj; Jarvandi, Soghra; Mohagheghi, Mohammad A; Hornby, David P; Dalton, Ann

    2002-01-01

    Background Breast cancer is the most common female malignancy and a major cause of death in middle-aged women. So far, germline mutations in the BRCA1 and BRCA2 genes in patients with early-onset breast and/or ovarian cancer have not been identified within the Iranian population. Methods With the collaboration of two main centres for cancer in Iran, we obtained clinical information, family history and peripheral blood from 83 women under the age of 45 with early-onset breast cancer for scanning of germline mutations in the BRCA1 and BRCA2 genes. We analysed BRCA1 exons 11 and BRCA2 exons 10 and 11 by the protein truncation test, and BRCA1 exons 2, 3, 5, 13 and 20 and BRCA2 exons 9, 17, 18 and 23 with the single-strand conformation polymorphism assay on genomic DNA amplified by polymerase chain reaction. Results Ten sequence variants were identified: five frameshifts (putative mutations – four novel); three missense changes of unknown significance and two polymorphisms, one seen commonly in both Iranian and British populations. Conclusions Identification of these novel mutations suggests that any given population should develop a mutation database for its programme of breast cancer screening. The pattern of mutations seen in the BRCA genes seems not to differ from other populations studied. Early-onset breast cancer (less than 45 years) and a limited family history is sufficient to justify mutation screening with a detection rate of over 25% in this group, whereas sporadic early-onset breast cancer (detection rate less than 5%) is unlikely to be cost-effective. PMID:12100744

  14. Analysis of BRCA1 and mtDNA haplotypes and mtDNA polymorphism in familial breast cancer.

    PubMed

    Gutiérrez Povedano, Cristina; Salgado, Josefa; Gil, Carmen; Robles, Maitane; Patiño-García, Ana; García-Foncillas, Jesús

    2015-04-01

    Mitochondrial DNA (mtDNA) defects have been postulated to play an important role in the modulation and/or progression of cancer. In the past decade, a wide spectrum of mtDNA variations have been suggested as potentially sensitive and specific biomarkers for several human cancer types. In this context, single nucleotide polymorphisms (SNPs) described as protective or risk variants have been published, in particular in breast cancer, though not without controversy. Moreover, many mtDNA haplogroups have been associated with different phenotypes and diseases. We genotyped 18 SNPs, 15 of them defining European mtDNA haplogroups, including SNPs described as protective or risk variants, 7 SNPs that determine BRCA1 haplotypes and a BRCA1 intron 7 polymorphism. We included in this study 90 Caucasian unrelated women with breast cancer with familial criteria and 96 controls. Our aim was to clarify the importance of any of these SNPs, mitochondrial haplogroups and BRCA1 haplotypes in the modulation of breast cancer. We detected no significant differences in the distribution of BRCA1 haplotypes between patients and controls. Haplogroup U and the 12308G variant of mtDNA were overrepresented within the control group (p = 0.005 and p = 0.036, respectively) compared to breast cancer. Finally, we identified a significant association between the BRCA1 intron 7 polymorphism and BRCA1 haplotypes. Specifically, (TTC)6/6 and (TTC)6/7 genotypes with the seven polymorphic site cassette of "H2-like" haplotypes, and the (TTC)7/7 genotype associated with the "H1-like" haplotypes (p < 0.001).

  15. Gain of function mutant p53 proteins cooperate with E2F4 to transcriptionally downregulate RAD17 and BRCA1 gene expression.

    PubMed

    Valenti, Fabio; Ganci, Federica; Fontemaggi, Giulia; Sacconi, Andrea; Strano, Sabrina; Blandino, Giovanni; Di Agostino, Silvia

    2015-03-20

    Genomic instability (IN) is a common feature of many human cancers. The TP53 tumour suppressor gene is mutated in approximately half of human cancers. Here, we show that BRCA1 and RAD17 genes, whose derived proteins play a pivotal role in DNA damage repair, are transcriptional targets of gain-of-function mutant p53 proteins. Indeed, high levels of mutp53 protein facilitate DNA damage accumulation and severely impair BRCA1 and RAD17 expression in proliferating cancer cells. The recruitment of mutp53/E2F4 complex onto specific regions of BRCA1 and RAD17 promoters leads to the inhibition of their expression. BRCA1 and RAD17 mRNA expression is reduced in HNSCC patients carrying TP53 mutations when compared to those bearing wt-p53 gene. Furthermore, the analysis of gene expression databases for breast cancer patients reveals that low expression of DNA repair genes correlates significantly with reduced relapse free survival of patients carrying TP53 gene mutations. Collectively, these findings highlight the direct involvement of transcriptionally active gain of function mutant p53 proteins in genomic instability through the impairment of DNA repair mechanisms.

  16. Large genomic rearrangement of BRCA1 and BRCA2 genes in familial breast cancer patients in Korea.

    PubMed

    Cho, Ja Young; Cho, Dae-Yeon; Ahn, Sei Hyun; Choi, Su-Youn; Shin, Inkyung; Park, Hyun Gyu; Lee, Jong Won; Kim, Hee Jeong; Yu, Jong Han; Ko, Beom Seok; Ku, Bo Kyung; Son, Byung Ho

    2014-06-01

    We screened large genomic rearrangements of the BRCA1 and BRCA2 genes in Korean, familial breast cancer patients. Multiplex ligation-dependent probe amplification assay was used to identify BRCA1 and BRCA2 genomic rearrangements in 226 Korean familial breast cancer patients with risk factors for BRCA1 and BRCA2 mutations, who previously tested negative for point mutations in the two genes. We identified only one large deletion (c.4186-1593_4676-1465del) in BRCA1. No large rearrangements were found in BRCA2. Our result indicates that large genomic rearrangement in the BRCA1 and BRCA2 genes does not seem like a major determinant of breast cancer susceptibility in the Korean population. A large-scale study needs to validate our result in Korea.

  17. 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

    Daniels, Sarah L; 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

  18. 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

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

    PubMed

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

    2015-02-01

    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 tRNA(Leu) 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.

  20. 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

  1. 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.

  2. Application of a miniature biochip using the molecular beacon probe in breast cancer gene BRCA1 detection.

    PubMed

    Culha, Mustafa; Stokes, David L; Griffin, Guy D; Vo-Dinh, Tuan

    2004-04-15

    We report for the first time the application of a biochip using the molecular beacon (MB) detection scheme. The usability of this biochip novel detection system for the analysis of the breast cancer gene BRCA1 is demonstrated using molecular beacon probes. The MB is designed for the BRCA1 gene and a miniature biochip system is used for detection. The performance of the biochip-MB detection system is evaluated. The optimum conditions for the MB system for highest fluorescence detection sensitivity are investigated for the detection system. The detection of BRCA1 gene is successfully demonstrated in solution and the limit of detection (LOD) is estimated as 70 nM.

  3. 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.

  4. 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

  5. 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

  6. 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

  7. Expression profile of BRCA1 and BRCA2 genes in premenopausal Mexican women with breast cancer: clinical and immunohistochemical correlates.

    PubMed

    Loredo-Pozos, Gloria; Chiquete, Erwin; Oceguera-Villanueva, Antonio; Panduro, Arturo; Siller-López, Fernando; Ramos-Márquez, Martha E

    2009-01-01

    Low BRCA1 gene expression is associated with increased invasiveness and influences the response of breast carcinoma (BC) to chemotherapeutics. However, expression of BRCA1 and BRCA2 genes has not been completely characterized in premenopausal BC. We analyzed the clinical and immunohistochemical correlates of BRCA1 and BRCA2 expression in young BC women. We studied 62 women (mean age 38.8 years) who developed BC before the age of 45 years. BRCA1 and BRCA2 mRNA expression was assessed by reverse transcriptase-polymerase chain reaction (RT-PCR) and that of HER-2 and p53 proteins by immunohistochemistry. Body mass index (BMI) > or = 27 (52%) and a declared family history of BC (26%) were the main risk factors. Ductal infiltrative adenocarcinoma was found in 86% of the cases (tumor size >5 cm in 48%). Disease stages I-IV occurred in 2, 40, 55, and 3%, respectively (73% implicating lymph nodes). Women aged < or = 35 years (24%) had more family history of cervical cancer, stage III/IV disease, HER-2 positivity, and lower BRCA1 expression than older women (P < 0.05). BRCA1 and BRCA2 expression correlated in healthy, but not in tumor tissues (TT). Neither BRCA1 nor BRCA2 expression was associated with tumor histology, differentiation, nodal metastasis or p53 and HER-2 expression. After multivariate analysis, only disease stage explained BRCA1 mRNA levels in the lowest quartile. Premenopausal BC has aggressive clinical and molecular characteristics. Low BRCA1 mRNA expression is associated mainly with younger ages and advanced clinical stage of premenopausal BC. BRCA2 expression is not associated with disease severity in young BC women.

  8. 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

  9. 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

  10. 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.

  11. 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

  12. BRCA1-like signature in triple negative breast cancer: Molecular and clinical characterization reveals subgroups with therapeutic potential.

    PubMed

    Severson, Tesa M; Peeters, Justine; Majewski, Ian; Michaut, Magali; Bosma, Astrid; Schouten, Philip C; Chin, Suet-Feung; Pereira, Bernard; Goldgraben, Mae A; Bismeijer, Tycho; Kluin, Roelof J C; Muris, Jettie J F; Jirström, Karin; Kerkhoven, Ron M; Wessels, Lodewyk; Caldas, Carlos; Bernards, René; Simon, Iris M; Linn, Sabine

    2015-10-01

    Triple negative (TN) breast cancers make up some 15% of all breast cancers. Approximately 10-15% are mutant for the tumor suppressor, BRCA1. BRCA1 is required for homologous recombination-mediated DNA repair and deficiency results in genomic instability. BRCA1-mutated tumors have a specific pattern of genomic copy number aberrations that can be used to classify tumors as BRCA1-like or non-BRCA1-like. BRCA1 mutation, promoter methylation, BRCA1-like status and genome-wide expression data was determined for 112 TN breast cancer samples with long-term follow-up. Mutation status for 21 known DNA repair genes and PIK3CA was assessed. Gene expression and mutation frequency in BRCA1-like and non-BRCA1-like tumors were compared. Multivariate survival analysis was performed using the Cox proportional hazards model. BRCA1 germline mutation was identified in 10% of patients and 15% of tumors were BRCA1 promoter methylated. Fifty-five percent of tumors classified as BRCA1-like. The functions of genes significantly up-regulated in BRCA1-like tumors included cell cycle and DNA recombination and repair. TP53 was found to be frequently mutated in BRCA1-like (P < 0.05), while PIK3CA was frequently mutated in non-BRCA1-like tumors (P < 0.05). A significant association with worse prognosis was evident for patients with BRCA1-like tumors (adjusted HR = 3.32, 95% CI = 1.30-8.48, P = 0.01). TN tumors can be further divided into two major subgroups, BRCA1-like and non-BRCA1-like with different mutation and expression patterns and prognoses. Based on these molecular patterns, subgroups may be more sensitive to specific targeted agents such as PI3K or PARP inhibitors.

  13. Lack of correlation between BRCA1 carrier status and HER-2/neu (ERBB2) gene amplification in breast cancer

    SciTech Connect

    Sanford, J.S.; Giraldez, R.A.; Flom, K.

    1994-09-01

    We examined 4{mu}m paraffin-embedded tissue sections from twenty female breast tumors for the presence of HER-2/neu (ERBB2) gene amplification. The study population consisted of ten BRCA1 carriers and ten non-BRCA1 carriers. Carrier status was assessed through linkage analysis. Detection of HER-2/neu gene amplification was performed blinded with respect to BRCA1 status. Forty cells representing at least two different areas of each tumor were analyzed by fluorescence in situ hybridization (FISH) using a HER-2/neu cosmid probe. We did not find any cases which showed the typical HER-2/neu gene amplification profile (homogeneous distribution of cells with > 4 signals per cell). In half of the cases, small foci that appeared amplified were identified as clusters of cells with > 4 signals. Modifying our analysis to compensate for this, cases were considered to be amplified if nine or more cells out of forty contained over four HER-2/neu signals. For the 10 BRCA1 carrier positive samples, 5 were HER-2/neu amplified and 5 were not. Similarly, of the 10 BRCA1 carrier negative samples, 5 were HER-2/neu amplified and 5 were not. Therefore, we found no statistical correlation between BRCA1 carrier status and amplification of the HER-2/neu gene in the tumors studied.

  14. 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.

  15. Mutational analysis of the breast cancer susceptibility gene BRIP1 /BACH1/FANCJ in high-risk non-BRCA1/BRCA2 breast cancer families.

    PubMed

    Guénard, Frédéric; Labrie, Yvan; Ouellette, Geneviève; Joly Beauparlant, Charles; Simard, Jacques; Durocher, Francine

    2008-01-01

    The BRIP1 gene encodes a helicase interacting with BRCA1, which contributes to BRCA1-associated DNA repair function. Germ-line BRIP1 mutations affecting the helicase domain activity have been identified in early onset breast cancer patients. In addition, BRIP1 was recently identified as deficient in Fanconi anemia (FA) complementation group J. Given the growing evidence now linking BRCA1, BRCA2, and the FA pathway, as well as the involvement of FA proteins (BRCA2/FANCD1 and PALB2/FANCN) in breast cancer susceptibility, we sought to evaluate the contribution of FANCJ gene alterations regarding breast cancer susceptibility among our cohort of 96 breast cancer individuals from high-risk non-BRCA1/2 French Canadian families. No deleterious mutation, exon deletion, or retention of intronic portions could be identified. However, extensive analysis of the promoter and whole exonic and flanking intronic regions of FANCJ led to the identification of 42 variants, including 22 novel variants not previously reported, four of which were located in the promoter region. Transcription factors analysis revealed a potential involvement of FANCJ promoter variants in regulation of FANCJ expression, and reporter gene assays were performed. The allelic frequency was assessed in a cohort of 73 unaffected French Canadian individuals, and haplotype analysis and tagging single nucleotide polymorphism (SNP) identification were also performed. Although our study unlikely involves FANCJ as a high-risk predisposition gene in non-BRCA1/2 high-risk French Canadian families, the possible association of FANCJ missense variants with phenotypes associated with FA, such as childhood cancer, cannot be excluded.

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

    PubMed

    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

    2014-09-01

    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.

  17. 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

  18. 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

  19. 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.

  20. 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

  1. Screening for the breast cancer gene (BRCA1) using a biochip system and molecular beacon probes immobilized on solid surfaces.

    PubMed

    Culha, Mustafa; Stokes, David L; Griffin, Guy D; Vo-Dinh, Tuan

    2004-01-01

    We describe the use of a biochip based on complementary metal oxide semiconductor (CMOS) technology for detection of specific genetic sequences using molecular beacons (MB) immobilized on solid surfaces as probes. The applicability of this miniature detection system for screening for the BRCA1 gene is evaluated using MB probes, designed especially for the BRCA1 gene. MB probes are immobilized on a zeta-probe membrane by biotin-streptavidin immobilization. Two immobilization strategies are investigated to obtain optimal assay sensitivity. The MB is immobilized by manual spotting on zeta-probe membrane surfaces with the use of a custom-made stamping system. The detection of the BRCA1 gene using an MB probe is successfully demonstrated and expands the use of the CMOS biochip for medical applications.

  2. Repair versus Checkpoint Functions of BRCA1 Are Differentially Regulated by Site of Chromatin Binding.

    PubMed

    Goldstein, Michael; Kastan, Michael B

    2015-07-01

    The product of the Brca1 tumor-suppressor gene is involved in multiple aspects of the cellular DNA damage response (DDR), including activation of cell-cycle arrests and DNA double-stranded break (DSB) repair by homologous recombination. Prior reports demonstrated that BRCA1 recruitment to areas of DNA breakage depended on RAP80 and the RNF8/RNF168 E3 ubiquitin ligases. Here, we extend these findings by showing that RAP80 is only required for the binding of BRCA1 to regions flanking the DSB, whereas BRCA1 binding directly to DNA breaks requires Nijmegen breakage syndrome 1 (NBS1). These differential recruitment mechanisms differentially affect BRCA1 functions: (i) RAP80-dependent recruitment of BRCA1 to chromatin flanking DNA breaks is required for BRCA1 phosphorylation at serine 1387 and 1423 by ATM and, consequently, for the activation of S and G(2) checkpoints; and (ii) BRCA1 interaction with NBS1 upon DSB induction results in an NBS1-dependent recruitment of BRCA1 directly to the DNA break and is required for nonhomologous end-joining repair. Together, these findings illustrate that spatially distinct fractions of BRCA1 exist at the DSB site, which are recruited by different mechanisms and execute different functions in the DDR.

  3. Role of BRCA1 in brain development.

    PubMed

    Pao, Gerald M; Zhu, Quan; Perez-Garcia, Carlos G; Chou, Shen-Ju; Suh, Hoonkyo; Gage, Fred H; O'Leary, Dennis D M; Verma, Inder M

    2014-04-01

    Breast cancer susceptibility gene 1 (BRCA1) is a breast and ovarian cancer tumor suppressor whose loss leads to DNA damage and defective centrosome functions. Despite its tumor suppression functions, BRCA1 is most highly expressed in the embryonic neuroepithelium when the neural progenitors are highly proliferative. To determine its functional significance, we deleted BRCA1 in the developing brain using a neural progenitor-specific driver. The phenotype is characterized by severe agenesis of multiple laminated cerebral structures affecting most notably the neocortex, hippocampus, cerebellum, and olfactory bulbs. Major phenotypes are caused by excess apoptosis, as these could be significantly suppressed by the concomitant deletion of p53. Certain phenotypes attributable to centrosomal and cell polarity functions could not be rescued by p53 deletion. A double KO with the DNA damage sensor kinase ATM was able to rescue BRCA1 loss to a greater extent than p53. Our results suggest distinct apoptotic and centrosomal functions of BRCA1 in neural progenitors, with important implications to understand the sensitivity of the embryonic brain to DNA damage, as well as the developmental regulation of brain size. PMID:24639535

  4. BRCA1 gene variant p.P142H associated with male breast cancer: a two-generation genealogic study and literature review.

    PubMed

    Spinelli, Claudio; Strambi, Silvia; Piccini, Lorenzo; Rossi, Leonardo; Aretini, Paolo; Caligo, Adelaide

    2015-12-01

    Breast cancer occurs rarely in male patient. BRCA1 gene mutation seems to be related to male breast cancer, but its role is not clearly defined. We have identified in a male patient affected by breast cancer the BRCA1 gene variant p.P142H. We performed a literature research using the keywords "male breast cancer", "male breast cancer mutations" and "BRCA" and we reviewed the cases. We found ew other studies regarding BRCA1 variant p.P142H, about female subjects. At the moment, BRCA1 gene variant p.P142H is not certainly classified as neutral or deleterious. Genetic testing for BRCA1 and BRCA2 and PALB2 mutation gene has been performed on our patient. Segregation analysis for this p.P142H BRCA1 variant has been extended to the second generation of the family. Genetic tests revealed a clear inheritance regarding the BRCA1 gene p. P142H variant. Of the eight patients with this specific genetic mutation, four presented breast cancer (bilateral in one case), two female and two male. None of the subjects in the family without the BRCA1 gene variant p. P142H presented breast cancer or other BRCA1 gene mutation-related cancers. Our analysis suggests that the BRCA1 gene variant p.P142H mutation is related with male breast cancer. Starting from these data, it can be inferred that more studies on MBC and its relation with the BRCA1 gene mutation P142H variant must be undertaken to improve prognostic and therapeutic strategies. PMID:26085381

  5. Polymorphic variations in the FANCA gene in high-risk non-BRCA1/2 breast cancer individuals from the French Canadian population.

    PubMed

    Litim, Nadhir; Labrie, Yvan; Desjardins, Sylvie; Ouellette, Geneviève; Plourde, Karine; Belleau, Pascal; Durocher, Francine

    2013-02-01

    The majority of genes associated with breast cancer susceptibility, including BRCA1 and BRCA2 genes, are involved in DNA repair mechanisms. Moreover, among the genes recently associated with an increased susceptibility to breast cancer, four are Fanconi Anemia (FA) genes: FANCD1/BRCA2, FANCJ/BACH1/BRIP1, FANCN/PALB2 and FANCO/RAD51C. FANCA is implicated in DNA repair and has been shown to interact directly with BRCA1. It has been proposed that the formation of FANCA/G (dependent upon the phosphorylation of FANCA) and FANCB/L sub-complexes altogether with FANCM, represent the initial step for DNA repair activation and subsequent formation of other sub-complexes leading to ubiquitination of FANCD2 and FANCI. As only approximately 25% of inherited breast cancers are attributable to BRCA1/2 mutations, FANCA therefore becomes an attractive candidate for breast cancer susceptibility. We thus analyzed FANCA gene in 97 high-risk French Canadian non-BRCA1/2 breast cancer individuals by direct sequencing as well as in 95 healthy control individuals from the same population. Among a total of 85 sequence variants found in either or both series, 28 are coding variants and 19 of them are missense variations leading to amino acid change. Three of the amino acid changes, namely Thr561Met, Cys625Ser and particularly Ser1088Phe, which has been previously reported to be associated with FA, are predicted to be damaging by the SIFT and PolyPhen softwares. cDNA amplification revealed significant expression of 4 alternative splicing events (insertion of an intronic portion of intron 10, and the skipping of exons 11, 30 and 31). In silico analyzes of relevant genomic variants have been performed in order to identify potential variations involved in the expression of these spliced transcripts. Sequence variants in FANCA could therefore be potential spoilers of the Fanconi-BRCA pathway and as a result, they could in turn have an impact in non-BRCA1/2 breast cancer families.

  6. BRCA1 as target for breast cancer prevention and therapy.

    PubMed

    Romagnolo, Alberto P G; Romagnolo, Donato F; Selmin, Ornella I

    2015-01-01

    The Breast Cancer 1 protein (BRCA1) is a tumor suppressor involved in basic cellular functions necessary for cell replication and DNA synthesis, but reduced expression of BRCA1, due to mutations or epigenetic inactivation, leads to impaired mammary gland differentiation and increased risk of breast cancer development. Although BRCA1 acts as a tumor suppressor and is present in all cells, where it is essential for the maintenance of the genome integrity, it is still not clear why mutations in the BRCA1 gene predispose to breast and ovarian, but not to other types of cancer. In the first part of this review, we briefly discuss the function and regulation of the BRCA1 protein, including its role associated with familial and sporadic breast cancer. The second part is an overview of the therapeutic compounds used for breast cancer treatment targeting BRCA1, and the natural food components that hold potential preventive effect against those types of breast cancer in which BRCA1 expression is either reduced or lacking. Further studies elucidating the interactions between dietary compounds and cellular pathways, involved in regulation of BRCA1expression, are necessary for the development of strategies that may successfully prevent or treat breast cancer.

  7. BRCA1 splice variants exhibit overlapping and distinct transcriptional transactivation activities.

    PubMed

    McEachern, Kristen A; Archey, William B; Douville, Karen; Arrick, Bradley A

    2003-05-01

    The global changes in gene expression induced by transient increased expression of full length BRCA1 as well as the spliced variant BRCA1(S) were evaluated by cDNA expression array in a human non-tumorigenic mammary epithelial cell line, MCF10A. Over 30 genes were identified that displayed an altered expression pattern in response to the expression of BRCA1 splice variants. The expression of NFkappaB inducing kinase was markedly down-regulated in BRCA1(L) transfected cells. However, a NFkappaB-responsive promoter construct yielded increased basal activity in BRCA1(L) transfected cells, as well as following treatment with tumor necrosis factor-alpha or lymphotoxin. In addition, nuclear extracts from BRCA1(L) transfected cells displayed increased DNA binding to the kappaB consensus site. The transcriptional activity of a panel of promoter constructs was evaluated following expression of wild type or mutant BRCA1. Full length BRCA1 transactivated the estrogen receptor-alpha (ERalpha) and BCL2 promoters as well as AP-1, SRE, and CRE containing promoters. Transactivation activity of the exon 11-deleted BRCA1(S) was more limited and usually of lower magnitude. The ability of a pathogenic mutation, 5382insC, to abrogate the transcriptional transactivation by BRCA1(L) and BRCA1(S) was also investigated. Mutant BRCA1 retained wild type levels of transcriptional activity for the ERalpha promoter as well as for the NFkappaB, AP-1, and CRE-responsive promoters but had reduced or no activity with the BCL2 and SRE promoters. These results show that BRCA1 isoforms have both overlapping and distinct transcriptional transactivation activity, and that a mutant form of BRCA1 implicated in carcinogenesis is not devoid of all activity.

  8. Promoter methylation and expression changes of BRCA1 in cancerous tissues of patients with sporadic breast cancer

    PubMed Central

    LI, QIUYUN; WEI, WEI; JIANG, YI; YANG, HUAWEI; LIU, JIANLUN

    2015-01-01

    BRCA1 is a susceptibility gene that has a genetic predisposition for breast cancer. BRCA1 gene mutation is closely associated with familial hereditary breast cancer, but the BRCA1 gene mutation is rarely found in sporadic breast cancer. According to previous studies, decreased expression of BRCA1 was detected in certain types of sporadic breast cancer. Aberrant methylation of DNA promoter CpG islands is one of the mechanisms by which tumor suppressor gene expression and function is lost. The aim of the present study was to investigate BRCA1 gene expression, methylation status and clinical significance in sporadic types of breast cancer. Quantitative polymerase chain reaction (PCR) and bisulfite sequencing PCR were respectively used to detect expression differences of BRCA1 mRNA and BRCA1 methylation in the 49 cancerous and paired non-cancerous samples from patients with breast cancer. The associations of BRCA1 expression and methylation status with the clinicopathologic characteristics were analysed. BRCA1 mRNA expression levels in the 49 breast cancer tissues were lower than those in the paired non-cancerous tissues. There was a significant statistical difference (P=0.001). BRCA1 mRNA expression was not associated with the main clinicopathologic characteristics. Frequency of the BRCA1 promoter methylation in the breast cancerous tissues was significantly higher than that in the non-cancerous tissues (P=0.007); BRCA1 gene methylation status was negatively correlated with mRNA expression (P=0.029); and BRCA1 methylation exhibited no association with all clinicopathological features. DNA promoter hypermethylation may be the potential mechanism accounting for BRCA1 expression silence in part of sporadic types of breast cancer. Some patients with hypermethylated BRCA1 may display favorable clinicopathological status. PMID:25789047

  9. 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

  10. 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

  11. Mutational analysis of BRCA1/2 gene and pathologic characteristics from Kazakh population with sporadic breast cancer in northwestern China.

    PubMed

    Yang, S Y; Aisimutula, D; Li, H F; Hu, Y; Du, X; Li, J; Luan, M X

    2015-10-27

    Mutations in the BRCA1/2 genes are associated with an increased risk of breast cancer, but no large-scale research have examined the BRCA1/2 mutations in Chinese Kazakh women. We evaluated the frequency and distributions of BRCA1 and BRCA2 gene mutations in Kazakh sporadic breast cancer patients and healthy women in China. The association between the clinical-pathologic features of Kazakh breast cancer patients and BRCA1/2 mutations were also investigated. Two unclassified variants (T539M and T1915M) and 16 polymorphisms were detected in this study, 4 of which (G356A, His743, Asn991Asp, Val1269) were detected more frequently in breast cancer patients than in healthy controls. We observed a higher prevalence of BRCA1/2 common sequence alterations and a large number of Kazakh women carrying multiple co-existing BRCA1/2 mutations. The prevalence of BRCA1 mutations was similar to that of BRCA2 mutations. Although no significant differences were observed, BRCA1/2 carriers were generally younger at diagnosis of wild-type breast cancer patients. BRCA1-associated Kazakh sporadic breast cancers present with high tumor grade, early stage, negative lymph node status, absence of estrogen receptor expression and progesterone-positive status. Estrogen receptor expression was the only predominant histological type in BRCA2 carriers. In this study, we determined the BRCA1 and BRCA2 gene mutation status and determined the association with clinical-pathologic characteristics in a Chinese Kazakh population. Larger population-based screening studies screening the entire coding region of BRCA1/2 are required to evaluate the breast cancer risk induced by the sequence alterations detected in this study.

  12. 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.

  13. 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

  14. 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

  15. 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

  16. BRCA1 promoter hypermethylation, 53BP1 protein expression and PARP-1 activity as biomarkers of DNA repair deficit in breast cancer

    PubMed Central

    2013-01-01

    Background Poly(adenosine diphosphate–ribose) polymerase 1 (PARP-1) and the balance between BRCA1 and 53BP1 play a key role in the DNA repair and cell stress response. PARP inhibitors show promising clinical activity in metastatic triple negative (TN) or BRCA-mutated breast cancer. However, a comprehensive analysis of PARP-1 activity, BRCA1 promoter methylation and 53BP1 expression in tumours without known BRCA1 mutation has not yet been carried out. Methods We investigated cytosolic PARP-1 activity, 53BP1 protein levels and BRCA1 promoter methylation in 155 surgical breast tumour samples from patients without familial breast cancer history or known BRCA1 mutations who were treated between January 2006 and November 2009 and evaluated their statistical association with classical predictive and prognostic factors. Results The mitotic count score was the only parameter clearly associated with PARP-1 activity. BRCA1 promoter hypermethylation (15.4% of all cancers) was significantly associated with uPA and PAI-1 levels, tumour grade, mitotic count score, hormone receptor and HER2 negative status and TN profile (29% of TN tumours showed BRCA1 promoter hypermethylation compared to 5% of grade II-III hormone receptor-positive/HER2-negative and 2% of HER2-positive tumours). No statistical association was found between BRCA1 promoter hypermethylation and PARP-1 activity. High 53BP1 protein levels correlated with lymph node positivity, hormone receptor positivity, molecular grouping, unmethylated BRCA1 promoter and PARP-1 activity. In TN tumours, BRCA1 promoter methylation was only marginally associated with age, PARP-1 activity was not associated with any of the tested clinico-pathological factors and high 53BP1 protein levels were significantly associated with lymph node positivity. Only 3 of the 14 TN tumours with BRCA1 promoter hypermethylation presented high 53BP1 protein levels. Conclusions Breast cancers that harbour simultaneously high 53BP1 protein level and BRCA1

  17. 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.

  18. Effectiveness of preventive interventions in BRCA1/2 gene mutation carriers: a systematic review.

    PubMed

    Bermejo-Pérez, M J; Márquez-Calderón, S; Llanos-Méndez, A

    2007-07-15

    A systematic review of the literature was conducted to assess the outcomes of preventive interventions (prophylactic surgery, intensive cancer screening, and chemoprevention) in women who carry mutations in BRCA1/2 genes, in terms of reducing breast and gynaecological cancer incidence and/or mortality. A search for relevant articles published between 1996 and 2005 (inclusive) was run on Medline, Embase and other databases. From the 749 journal articles retrieved from this search strategy, 18 studies were eligible for this review (2 systematic reviews, 10 cohort studies and 6 case-control studies). The critical appraisal of the studies was performed by two independent reviewers with a list of ad hoc selected criteria. The synthesis of results was qualitative. Mastectomy and prophylactic gynaecological surgery (oophorectomy or salpingo-oophorectomy) reduced breast and gynaecological cancer incidence in carriers of BRCA mutations, by comparison to surveillance. However, all the studies presented flaws in internal and external validity, none of these preventive interventions is risk-free, and protection against breast and gynaecological cancer, as well as other cancers linked to BRCA mutations, is incomplete. No studies comparing surveillance programmes of varying intensity were found. Exposure to drugs (tamoxifen, and oral contraceptives) in women carrying BRCA mutations was assessed through a limited number of papers. All of these were case-control studies with prevalent cases and presented major methodological flaws.

  19. 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

  20. 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 1 aM to 10 pM. 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.

  1. A high incidence of BRCA1 mutations in 20 breast-ovarian cancer families.

    PubMed Central

    Serova, O.; Montagna, M.; Torchard, D.; Narod, S. A.; Tonin, P.; Sylla, B.; Lynch, H. T.; Feunteun, J.; Lenoir, G. M.

    1996-01-01

    We have analyzed 20 breast-ovarian cancer families, the majority of which show positive evidence of linkage to chromosome 17q12 for germ-line mutations in the BRCA1 gene. BRCA1 mutations cosegregating with breast and ovarian cancer susceptibility were identified in 16 families, including 1 family with a case of male breast cancer. Nine of these mutations have not been reported previously. The majority of mutations were found to generate a premature stop codon leading to the formation of a truncated BRCA1 protein of 2%-88% of the expected normal length. Two mutations altered the RING finger domain. Sequencing of genomic DNA led to the identification of a mutation in the coding region of BRCA1 in 12 families, and cDNA analysis revealed an abnormal or missing BRCA1 transcript in 4 of the 8 remaining families. A total of eight mutations were associated with a reduced quantity of BRCA1 transcript. We were unable to detect BRCA1 mutations in 4 of the 20 families, but only 1 of these was clearly linked to BRCA1. It is expected that the majority of clear examples of the breast-ovarian syndrome will be associated with germ-line mutations in the coding region of BRCA1. Images Figure 1 PMID:8554067

  2. A high incidence of BRCA1 mutations in 20 breast-ovarian cancer families

    SciTech Connect

    Serova, O.; Montagna, M.; Sylla, B.

    1996-01-01

    We have analyzed 20 breast-ovarian cancer families, the majority of which show positive evidence of linkage to chromosome 17q12, for germ-line mutations in the BRCA1 gene. BRCA1 mutations cosegregating with breast and ovarian cancer susceptibility were identified in 16 families, including 1 family with a case of male breast cancer. Nine of these mutations have not been reported previously. The majority of mutations were found to generate a premature stop codon leading to the formation of a truncated BRCA1 protein of 2%-88% of the expected normal length. Two mutations altered the RING finger domain. Sequencing of genomic DNA led to the identification of a mutation in the coding region of BRCA1 in 12 families, and cDNA analysis revealed an abnormal or missing BRCA1 transcript in 4 of the 8 remaining families. A total of eight mutations were associated with a reduced quantity of BRCA1 transcript. We were unable to detect BRCA1 mutations in 4 of the 20 families, but only 1 of these was clearly linked to BRCA1. It is expected that the majority of clear examples of the breast-ovarian cancer syndrome will be associated with germ-line mutations in the coding region of BRCA1. 30 refs., 4 figs., 3 tabs.

  3. Studying therapy response and resistance in mouse models for BRCA1-deficient breast cancer.

    PubMed

    Michalak, Ewa Malgorzata; Jonkers, Jos

    2011-04-01

    Worldwide, more than one million women are diagnosed with breast cancer every year, making it the most common malignancy of females in the developed world. Germline mutations in the breast cancer susceptibility genes BRCA1 and BRCA2 account for 4-6% of all breast cancer cases, and mutation carriers have a lifetime risk of 80% for developing breast cancer and 40% for developing ovarian cancer. Current treatment options are limited and often do not lead to cure. In the 17 years since the discovery of BRCA1, the generation of mouse models for BRCA1 deficiency has greatly aided our understanding of it's role in tumorigenesis. In contrast to human BRCA1 mutation carriers, mice carrying heterozygous mutations in Brca1 did not develop spontaneous tumors. This led to the generation of conditional mouse models in which tissue-specific Brca1 deletion induces formation of mammary tumors that closely resemble human BRCA1-mutated breast tumors. These models have proven useful for studying BRCA1-related tumor development, drug response and resistance. BRCA1-deficient cancer cells are defective in DNA repair mediated by homologous recombination (HR) and therefore highly sensitive to DNA-damaging agents such as platinum drugs and poly(ADP-ribose) polymerase (PARP) inhibitors. However, BRCA1-mutated tumors can develop resistance to these drugs; hence improved treatment strategies are critical. Existing mouse models have already proven useful for preclinical testing of (combinations of) therapeutic agents that may be beneficial for the treatment of patients with BRCA1-mutated tumors. In this review, we discuss the progress made towards modeling BRCA1-deficient breast cancer in mice and what we have learned from preclinical studies using these models.

  4. 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

  5. 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

  6. BRCA1 Is Required for Maintenance of Phospho-Chk1 and G2/M Arrest during DNA Cross-Link Repair in DT40 Cells

    PubMed Central

    Draga, Margarethe; Madgett, Elizabeth B.; Vandenberg, Cassandra J.; du Plessis, David; Kaufmann, Aisling; Werler, Petra; Chakraborty, Prasun; Lowndes, Noel F.

    2015-01-01

    The Fanconi anemia DNA repair pathway is pivotal for the efficient repair of DNA interstrand cross-links. Here, we show that FA-defective (Fancc−) DT40 cells arrest in G2 phase following cross-link damage and trigger apoptosis. Strikingly, cell death was reduced in Fancc− cells by additional deletion of the BRCA1 tumor suppressor, resulting in elevated clonogenic survival. Increased resistance to cross-link damage was not due to loss of toxic BRCA1-mediated homologous recombination but rather through the loss of a G2 checkpoint. This proapoptotic role also required the BRCA1-A complex member ABRAXAS (FAM175A). Finally, we show that BRCA1 promotes G2 arrest and cell death by prolonging phosphorylation of Chk1 on serine 345 after DNA damage to sustain arrest. Our data imply that DNA-induced cross-link death in cells defective in the FA pathway is dependent on the ability of BRCA1 to prolong cell cycle arrest in G2 phase. PMID:26324327

  7. BRCA1: a new candidate gene for bovine mastitis and its association analysis between single nucleotide polymorphisms and milk somatic cell score.

    PubMed

    Yuan, Zhengrong; Chu, Guiyan; Dan, Yang; Li, Jiao; Zhang, Lupei; Gao, Xue; Gao, Huijiang; Li, Junya; Xu, Shangzhong; Liu, Zhihua

    2012-06-01

    Bovine mastitis is a very complex and common disease of dairy cattle and a major source of economic losses to the dairy industry worldwide. In this study, the bovine breast cancer 1, early onset gene (BRCA1) was taken as a candidate gene for mastitis resistance. The main object of this study was to investigate whether the BRCA1 gene was associated with mastitis in cattle. Through DNA sequencing, Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) and Created Restriction Site PCR (CRS-PCR) methods, three SNPs (G22231T, T25025A, and C28300A) were detected and twenty-four combinations of these SNPs were observed. The single SNP and their genetic effects on somatic cell score (SCS) were evaluated and a significant association with SCS was found in C28300A. The mean of genotype EE was significantly lower than those of genotypes EF and FF. The results of combined genotypes analysis of three SNPs showed that BBDDFF genotype with the highest SCS were easily for the mastitis susceptibility, whereas AACCEE genotype with the lowest SCS were favorable for the mastitis resistance. The information provided in the present study will be very useful for improving mastitis resistance in dairy cattle by marker-assisted selection.

  8. 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

  9. Polymorphisms in the BRCA1 and ABCB1 genes modulate menopausal hormone therapy associated breast cancer risk in postmenopausal women.

    PubMed

    2010-04-01

    Menopausal hormone therapy (HT) is associated with an increased breast cancer risk among postmenopausal women. In this study, we investigated genetic effect modification of HT associated breast cancer risk in 3,149 postmenopausal breast cancer patients and 5,489 controls from the two German population-based case-control studies MARIE and GENICA. Twenty-eight polymorphisms of 14 candidate genes including two drug and hormone transporter genes (ABCB1/MDR1 and SHBG), four genes involved in cell cycle regulation (BRCA1, P21/CDKN1A, STK15/AURKA and TP53), six cytokine genes (IGFBP3, IL6, TGFB1, TNF, LTA and IGF1), and two cytokine receptor genes (EGFR and ERBB2) were genotyped using validated methods. Conditional logistic regression was used to assess multiplicative statistical interaction between polymorphisms and duration of estrogen-progestagen therapy and estrogen monotherapy use with regard to breast cancer risk assuming log-additive and co-dominant modes of inheritance. Women homozygous for the major ABCB1_rs2214102_G allele were found to be at a significantly increased breast cancer risk associated with combined estrogen-progestagen therapy [odds ratio (OR) = 1.17, 95% confidence interval (CI) = 1.12-1.23, P (interaction) = 0.022]. Additionally, risk associated with estrogen monotherapy was modified by BRCA1_rs799917. We observed a trend with increasing minor T alleles leading to the highest risk in homozygous carriers of the minor allele [OR (95% CI) = 1.17 (0.98-1.39), 1.06 (0.98-1.14), and 1.02 (0.94-1.11) for homozygous minor, heterozygous, and homozygous major allele carriers, respectively; P (interaction) = 0.032]. Our results suggest that genetic variants in ABCB1 and BRCA1 may modify the effect of HT on postmenopausal breast cancer risk.

  10. 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

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

    PubMed Central

    Kan, Charlene; Zhang, Junran

    2015-01-01

    DNA repair, particularly DNA double strand breaks (DSBs) repair, is essential for the survival of both normal and cancer cells. An elaborate repair mechanism has been developed in cells in order to efficiently repair the damaged DNA. The pathways that are predominately involved in DSBs repair are homologous recombination (HR) and classical nonhomologous end-joining (cNHEJ) although alternative NHEJ (aNHEJ), a third DSBs repair pathway, may also be important in certain contexts. The protein of BRCA1 encoded by the tumor suppressor gene BRCA1 regulates all DSBs repair pathways. Given the fact that DSBs represent the most biologically significant lesions induced by ionizing radiation (IR) and impaired DSBs repair leads to radiation sensitivity it has been expected that cancer patients with BRCA1 mutations should benefit from radiation therapy (RT). However, the clinical data are conflicting and inconclusive. Here, we provide an overview about the current status of the data regarding BRCA1 deficiency and RT sensitivity in both experimental models and clinical investigations. In addition, we will discuss a strategy to potentiate the effects of RT by poly(ADP ribose) polymerase (PARP) inhibitors, the pharmacologic drugs that are being investigated as a monotherapy for the treatment of patients with BRCA 1/2 mutations. PMID:26383678

  12. 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.

  13. 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

  14. Expression of cancer related BRCA1 missense variants decreases MMS-induced recombination in Saccharomyces cerevisiae without altering its nuclear localization.

    PubMed

    Lodovichi, Samuele; Vitello, Martina; Cervelli, Tiziana; Galli, Alvaro

    2016-10-17

    BRCA1 tumor suppressor gene is found mutated in familial breast and ovarian cancer. Most cancer related mutations were found located at the RING (Really Interesting New Gene) and at the BRCT (BRca1 C-Terminal) domain. However, 20 y after its identification, the biological role of BRCA1 and which domains are more relevant for tumor suppression are still being elucidated. We previously reported that expression of BRCA1 cancer related variants in the RING and BRCT domain increases spontaneous homologous recombination in yeast indicating that BRCA1 may interact with yeast DNA repair/recombination. To finally demonstrate whether BRCA1 interacts with yeast DNA repair, we exposed yeast cells expressing BRCA1wt, the cancer-related variants C-61G and M1775R to different doses of the alkylating agent methyl methane-sulfonate (MMS) and then evaluated the effect on survival and homologous recombination. Cells expressing BRCA1 cancer variants were more sensitive to MMS and less inducible to recombination as compared to cell expressing BRCA1wt. Moreover, BRCA1-C61G and -M1775R did not change their nuclear localization form as compared to the BRCA1wt or the neutral variant R1751Q indicating a difference in the DNA damage processing. We propose a model where BRCA1 cancer variants interact with the DNA double strand break repair pathways producing DNA recombination intermediates, that maybe less repairable and decrease MMS-induced recombination and survival. Again, this study strengthens the use of yeast as model system to characterize the mechanisms leading to cancer in humans carrying the BRCA1 missense variant.

  15. 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

  16. p53 suppresses hyper-recombination by modulating BRCA1 function.

    PubMed

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

    2015-09-01

    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.

  17. 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

  18. Expression of DNA Damage Response Molecules PARP1, γH2AX, BRCA1, and BRCA2 Predicts Poor Survival of Breast Carcinoma Patients1

    PubMed Central

    Park, See-Hyoung; Noh, Sang Jae; Kim, Kyoung Min; Bae, Jun Sang; Kwon, Keun Sang; Jung, Sung Hoo; Kim, Jung Ryul; Lee, Ho; Chung, Myoung Ja; Moon, Woo Sung; Kang, Myoung Jae; Jang, Kyu Yun

    2015-01-01

    BACKGROUND: Poly(ADP-ribose) polymerase 1 (PARP1), γH2AX, BRCA1, and BRCA2 are conventional molecular indicators of DNA damage in cells and are often overexpressed in various cancers. In this study, we aimed, using immunohistochemical detection, whether the co-expression of PARP1, γH2AX, BRCA1, and BRCA2 in breast carcinoma (BCA) tissue can provide more reliable prediction of survival of BCA patients. MATERIALS AND METHODS: We investigated immunohistochemical expression and prognostic significance of the expression of PARP1, γH2AX, BRCA1, and BRCA2 in 192 cases of BCAs. RESULTS: The expression of these four molecules predicted earlier distant metastatic relapse, shorter overall survival (OS), and relapse-free survival (RFS) by univariate analysis. Multivariate analysis revealed the expression of PARP1, γH2AX, and BRCA2 as independent poor prognostic indicators of OS and RFS. In addition, the combined expressional pattern of BRCA1, BRCA2, PARP1, and γH2AX (CSbbph) was an additional independent prognostic predictor for OS (P < .001) and RFS (P < .001). The 10-year OS rate was 95% in the CSbbph-low (CSbbph scores 0 and 1) subgroup, but that was only 35% in the CSbbph-high (CSbbph score 4) subgroup. CONCLUSION: This study has demonstrated that the individual and combined expression patterns of PARP1, γH2AX, BRCA1, and BRCA2 could be helpful in determining an accurate prognosis for BCA patients and for the selection of BCA patients who could potentially benefit from anti-PARP1 therapy with a combination of genotoxic chemotherapeutic agents. PMID:26310369

  19. 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

  20. An RNF168 fragment defective for focal accumulation at DNA damage is proficient for inhibition of homologous recombination in BRCA1 deficient cells

    PubMed Central

    Muñoz, Meilen C.; Yanez, Diana A.; Stark, Jeremy M.

    2014-01-01

    The E3 ubiquitin ligase RNF168 is a DNA damage response (DDR) factor that promotes monoubiquitination of H2A/H2AX at K13/15, facilitates recruitment of other DDR factors (e.g. 53BP1) to DNA damage, and inhibits homologous recombination (HR) in cells deficient in the tumor suppressor BRCA1. We have examined the domains of RNF168 important for these DDR events, including chromosomal HR that is induced by several nucleases (I-SceI, CAS9-WT and CAS9-D10A), since the inducing nuclease affects the relative frequency of distinct repair outcomes. We found that an N-terminal fragment of RNF168 (1-220/N221*) efficiently inhibits HR induced by each of these nucleases in BRCA1 depleted cells, and promotes recruitment of 53BP1 to DNA damage and H2AX monoubiquitination at K13/15. Each of these DDR events requires a charged residue in RNF168 (R57). Notably, RNF168-N221* fails to self-accumulate into ionizing radiation induced foci (IRIF). Furthermore, expression of RNF168 WT and N221* can significantly bypass the role of another E3 ubiquitin ligase, RNF8, for inhibition of HR in BRCA1 depleted cells, and for promotion of 53BP1 IRIF. We suggest that the ability for RNF168 to promote H2A/H2AX monoubiquitination and 53BP1 IRIF, but not RNF168 self-accumulation into IRIF, is important for inhibition of HR in BRCA1 deficient cells. PMID:24829461

  1. Genetic heterogeneity and penetrance analysis of the BRCA1 and BRCA2 genes in breast cancer families. The Breast Cancer Linkage Consortium.

    PubMed Central

    Ford, D; Easton, D F; Stratton, M; Narod, S; Goldgar, D; Devilee, P; Bishop, D T; Weber, B; Lenoir, G; Chang-Claude, J; Sobol, H; Teare, M D; Struewing, J; Arason, A; Scherneck, S; Peto, J; Rebbeck, T R; Tonin, P; Neuhausen, S; Barkardottir, R; Eyfjord, J; Lynch, H; Ponder, B A; Gayther, S A; Zelada-Hedman, M

    1998-01-01

    The contribution of BRCA1 and BRCA2 to inherited breast cancer was assessed by linkage and mutation analysis in 237 families, each with at least four cases of breast cancer, collected by the Breast Cancer Linkage Consortium. Families were included without regard to the occurrence of ovarian or other cancers. Overall, disease was linked to BRCA1 in an estimated 52% of families, to BRCA2 in 32% of families, and to neither gene in 16% (95% confidence interval [CI] 6%-28%), suggesting other predisposition genes. The majority (81%) of the breast-ovarian cancer families were due to BRCA1, with most others (14%) due to BRCA2. Conversely, the majority of families with male and female breast cancer were due to BRCA2 (76%). The largest proportion (67%) of families due to other genes was found in families with four or five cases of female breast cancer only. These estimates were not substantially affected either by changing the assumed penetrance model for BRCA1 or by including or excluding BRCA1 mutation data. Among those families with disease due to BRCA1 that were tested by one of the standard screening methods, mutations were detected in the coding sequence or splice sites in an estimated 63% (95% CI 51%-77%). The estimated sensitivity was identical for direct sequencing and other techniques. The penetrance of BRCA2 was estimated by maximizing the LOD score in BRCA2-mutation families, over all possible penetrance functions. The estimated cumulative risk of breast cancer reached 28% (95% CI 9%-44%) by age 50 years and 84% (95% CI 43%-95%) by age 70 years. The corresponding ovarian cancer risks were 0.4% (95% CI 0%-1%) by age 50 years and 27% (95% CI 0%-47%) by age 70 years. The lifetime risk of breast cancer appears similar to the risk in BRCA1 carriers, but there was some suggestion of a lower risk in BRCA2 carriers <50 years of age. PMID:9497246

  2. Minding the gap: The underground functions of BRCA1 and BRCA2 at stalled replication forks

    PubMed Central

    Nagaraju, Ganesh; Scully, Ralph

    2010-01-01

    The hereditary breast and ovarian cancer predisposition genes, BRCA1 and BRCA2, participate in the repair of DNA double strand breaks by homologous recombination. Circumstantial evidence implicates these genes in recombinational responses to DNA polymerase stalling during the S phase of the cell cycle. These responses play a key role in preventing genomic instability and cancer. Here, we review the current literature implicating the BRCA pathway in HR at stalled replication forks and explore the hypothesis that BRCA1 and BRCA2 participate in the recombinational resolution of single stranded DNA lesions termed “daughter strand gaps”, generated during replication across a damaged DNA template. PMID:17379580

  3. Genetic sequence variations of BRCA1-interacting genes AURKA, BAP1, BARD1 and DHX9 in French Canadian families with high risk of breast cancer.

    PubMed

    Guénard, Frédéric; Labrie, Yvan; Ouellette, Geneviève; Beauparlant, Charles Joly; Durocher, Francine

    2009-03-01

    Breast cancer is a heterogeneous disease displaying some degree of familial clustering. Highly penetrant breast cancer susceptibility genes represent approximately 20-25% of the familial aggregation of breast cancer. A significant proportion of this familial aggregation of breast cancer is thus yet to be explained by other breast cancer susceptibility genes. Given the high susceptibility conferred by the two major breast cancer predisposition genes, BRCA1 and BRCA2 and the implication of these genes in many key cellular processes, assessment of genes encoding BRCA1-interacting proteins as plausible breast cancer candidate genes is thus attractive. In this study, four genes encoding BRCA1-interacting proteins were analyzed in a cohort of 96 breast cancer individuals from high-risk non-BRCA1/BRCA2 French Canadian families. Although no deleterious truncating germline mutations or aberrant spliced mRNA species were identified, a total of 10, 4, 11 and 6 variants were found in the AURKA, BAP1, BARD1 and DHX9 genes, respectively. The allele frequency of each variant was further ascertained in a cohort of 98 healthy French Canadian unrelated women and a difference in allele frequency was observed for one BARD1 variant based on single-marker analysis. Haplotype estimation, haplotype blocks and tagging SNPs identification were then performed for each gene, providing a valuable tool for further searches of common disease-associated variants in these genes and therefore further analyses on these genes in larger cohorts is warranted in the search of low-to-moderate penetrance breast cancer susceptibility alleles.

  4. 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.

  5. 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

  6. Monozygotic twins discordant for constitutive BRCA1 promoter methylation, childhood cancer and secondary cancer.

    PubMed

    Galetzka, Danuta; Hansmann, Tamara; El Hajj, Nady; Weis, Eva; Irmscher, Benjamin; Ludwig, Marco; Schneider-Rätzke, Brigitte; Kohlschmidt, Nicolai; Beyer, Vera; Bartsch, Oliver; Zechner, Ulrich; Spix, Claudia; Haaf, Thomas

    2012-01-01

    We describe monozygotic twins discordant for childhood leukemia and secondary thyroid carcinoma. We used bisulfite pyrosequencing to compare the constitutive promoter methylation of BRCA1 and several other tumor suppressor genes in primary fibroblasts. The affected twin displayed an increased BRCA1 methylation (12%), compared with her sister (3%). Subsequent bisulfite plasmid sequencing demonstrated that 13% (6 of 47) BRCA1 alleles were fully methylated in the affected twin, whereas her sister displayed only single CpG errors without functional implications. This between-twin methylation difference was also found in irradiated fibroblasts and untreated saliva cells. The BRCA1 epimutation may have originated by an early somatic event in the affected twin: approximately 25% of her body cells derived from different embryonic cell lineages carry one epigenetically inactivated BRCA1 allele. This epimutation was associated with reduced basal protein levels and a higher induction of BRCA1 after DNA damage. In addition, we performed a genome-wide microarray analysis of both sisters and found several copy number variations, i.e., heterozygous deletion and reduced expression of the RSPO3 gene in the affected twin. This monozygotic twin pair represents an impressive example of epigenetic somatic mosaicism, suggesting a role for constitutive epimutations, maybe along with de novo genetic alterations in recurrent tumor development.

  7. 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.

  8. FOXA1 repression is associated with loss of BRCA1 and increased promoter methylation and chromatin silencing in breast cancer.

    PubMed

    Gong, C; Fujino, K; Monteiro, L J; Gomes, A R; Drost, R; Davidson-Smith, H; Takeda, S; Khoo, U S; Jonkers, J; Sproul, D; Lam, E W-F

    2015-09-24

    FOXA1 expression correlates with the breast cancer luminal subtype and patient survival. RNA and protein analysis of a panel of breast cancer cell lines revealed that BRCA1 deficiency is associated with the downregulation of FOXA1 expression. Knockdown of BRCA1 resulted in the downregulation of FOXA1 expression and enhancement of FOXA1 promoter methylation in MCF-7 breast cancer cells, whereas the reconstitution of BRCA1 in Brca1-deficent mouse mammary epithelial cells (MMECs) promoted Foxa1 expression and methylation. These data suggest that BRCA1 suppresses FOXA1 hypermethylation and silencing. Consistently, the treatment of MMECs with the DNA methylation inhibitor 5-aza-2'-deoxycitydine induced Foxa1 mRNA expression. Furthermore, treatment with GSK126, an inhibitor of EZH2 methyltransferase activity, induced FOXA1 expression in BRCA1-deficient but not in BRCA1-reconstituted MMECs. Likewise, the depletion of EZH2 by small interfering RNA enhanced FOXA1 mRNA expression. Chromatin immunoprecipitation (ChIP) analysis demonstrated that BRCA1, EZH2, DNA methyltransferases (DNMT)1/3a/3b and H3K27me3 are recruited to the endogenous FOXA1 promoter, further supporting the hypothesis that these proteins interact to modulate FOXA1 methylation and repression. Further co-immunoprecipitation and ChIP analysis showed that both BRCA1 and DNMT3b form complexes with EZH2 but not with each other, consistent with the notion that BRCA1 binds to EZH2 and negatively regulates its methyltransferase activity. We also found that EZH2 promotes and BRCA1 impairs the deposit of the gene silencing histone mark H3K27me3 on the FOXA1 promoter. These associations were validated in a familial breast cancer patient cohort. Integrated analysis of the global gene methylation and expression profiles of a set of 33 familial breast tumours revealed that FOXA1 promoter methylation is inversely correlated with the transcriptional expression of FOXA1 and that BRCA1 mutation breast cancer is significantly

  9. 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.

  10. [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.

  11. Cell biology of cancer: BRCA1 and sister chromatid pairing reactions?

    PubMed

    Skibbens, Robert V

    2008-02-15

    A significant portion of familial breast/ovarian cancer patients harbors a mutation in Breast Cancer Associated gene 1 (BRCA1). Cells deficient for BRCA1 exhibit chromosome aberrations such as whole chromosome duplications, translocations, inter-sister gaps and gene mis-regulation. Here, new evidence is reviewed that defects in sister chromatid cohesion may contribute directly to cancer cell phenotypes-especially those of BRCA1 mutant cells. Linking cohesion to BRCA1-dependent tumorigenesis are reports that BRCA1-associated components (DNA helicase, RFC, PCNA and genome surveillance factors) are required for efficient sister chromatid cohesion. Other cohesion factors (WAPL, EFO2/ESCO2 and hSecurin) are tightly correlated with various cell-type specific carcinogenesis, in support of a generalized model for cohesion in cancer. Recent findings further reveal that a reciprocal relationship exists in that DNA damage induces new Ctf7/Eco1-dependent sister chromatid pairing reactions that, in turn, are required for efficient DNA repair. Future research into sister chromatid pairing mechanisms are likely to provide critical new insights into the underlying causes of cancer.

  12. Molecular classification of familial non-BRCA1/BRCA2 breast cancer.

    PubMed

    Hedenfalk, Ingrid; Ringner, Markus; Ben-Dor, Amir; Yakhini, Zohar; Chen, Yidong; Chebil, Gunilla; Ach, Robert; Loman, Niklas; Olsson, Håkan; Meltzer, Paul; Borg, Ake; Trent, Jeffrey

    2003-03-01

    In the decade since their discovery, the two major breast cancer susceptibility genes BRCA1 and BRCA2, have been shown conclusively to be involved in a significant fraction of families segregating breast and ovarian cancer. However, it has become equally clear that a large proportion of families segregating breast cancer alone are not caused by mutations in BRCA1 or BRCA2. Unfortunately, despite intensive effort, the identification of additional breast cancer predisposition genes has so far been unsuccessful, presumably because of genetic heterogeneity, low penetrance, or recessive/polygenic mechanisms. These non-BRCA1/2 breast cancer families (termed BRCAx families) comprise a histopathologically heterogeneous group, further supporting their origin from multiple genetic events. Accordingly, the identification of a method to successfully subdivide BRCAx families into recognizable groups could be of considerable value to further genetic analysis. We have previously shown that global gene expression analysis can identify unique and distinct expression profiles in breast tumors from BRCA1 and BRCA2 mutation carriers. Here we show that gene expression profiling can discover novel classes among BRCAx tumors, and differentiate them from BRCA1 and BRCA2 tumors. Moreover, microarray-based comparative genomic hybridization (CGH) to cDNA arrays revealed specific somatic genetic alterations within the BRCAx subgroups. These findings illustrate that, when gene expression-based classifications are used, BRCAx families can be grouped into homogeneous subsets, thereby potentially increasing the power of conventional genetic analysis.

  13. 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

  14. 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

    Gambino, Gaetana; Tancredi, Mariella; Falaschi, Elisabetta; Aretini, Paolo; Caligo, Maria Adelaide

    2015-04-01

    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 occurring 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.

  15. 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.

  16. 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.

  17. 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.

  18. Analysis of BRCA1 Variants in Double-Strand Break Repair by Homologous Recombination and Single-Strand Annealing

    PubMed Central

    Towler, William I.; Zhang, Jie; Ransburgh, Derek J. R.; Toland, Amanda E.; Ishioka, Chikashi; Chiba, Natsuko; Parvin, Jeffrey D.

    2014-01-01

    Missense substitutions of uncertain clinical significance in the BRCA1 gene are a vexing problem in genetic counseling for women who have a family history of breast cancer. In this study, we evaluated the functions of 29 missense substitutions of BRCA1 in two DNA repair pathways. Repair of double-strand breaks by homology-directed recombination (HDR) had been previously analyzed for 16 of these BRCA1 variants, and 13 more variants were analyzed in this study. All 29 variants were also analyzed for function in double-strand break repair by the single-strand annealing (SSA) pathway. We found that among the pathogenic mutations in BRCA1, all were defective for DNA repair by either pathway. The HDR assay was accurate because all pathogenic mutants were defective for HDR, and all nonpathogenic variants were fully functional for HDR. Repair by SSA accurately identified pathogenic mutants, but several nonpathogenic variants were scored as defective or partially defective. These results indicated that specific amino acid residues of the BRCA1 protein have different effects in the two related DNA repair pathways, and these results validate the HDR assay as highly correlative with BRCA1-associated breast cancer. PMID:23161852

  19. 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

  20. Expression of human BRCA1 variants in mouse ES cells allows functional analysis of BRCA1 mutations.

    PubMed

    Chang, Suhwan; Biswas, Kajal; Martin, Betty K; Stauffer, Stacey; Sharan, Shyam K

    2009-10-01

    To date, inheritance of a mutant BRCA1 or BRCA2 gene is the best-established indicator of an increased risk of developing breast cancer. Sequence analysis of these genes is being used to identify BRCA1/2 mutation carriers, though these efforts are hampered by the high frequency of variants of unknown clinical significance (VUSs). Functional evaluation of such variants has been restricted due to lack of a physiologically relevant assay. In this study we developed a functional assay using mouse ES cells to study variants of BRCA1. We introduced BAC clones with human wild-type BRCA1 or variants into Brca1-null ES cells and confirmed that only wild-type and a known neutral variant rescued cell lethality. The same neutral variant was also able to rescue embryogenesis in Brca1-null mice. A test of several BRCT domain mutants revealed all to be deleterious, including a VUS. Furthermore, we used this assay to determine the effects of BRCA1 variants on cell cycle regulation, differentiation, and genomic stability. Importantly, we discovered that ES cells rescued by S1497A BRCA1 exhibited significant hypersensitivity after gamma-irradiation. Our results demonstrate that this ES cell-based assay is a powerful and reliable method for analyzing the functional impact of BRCA1 variants, which we believe could be used to determine which patients may require preventative treatments. PMID:19770520

  1. BRCA1 interaction of centrosomal protein Nlp is required for successful mitotic progression.

    PubMed

    Jin, Shunqian; Gao, Hua; Mazzacurati, Lucia; Wang, Yang; Fan, Wenhong; Chen, Qiang; Yu, Wei; Wang, Mingrong; Zhu, Xueliang; Zhang, Chuanmao; Zhan, Qimin

    2009-08-21

    Breast cancer susceptibility gene BRCA1 is implicated in the control of mitotic progression, although the underlying mechanism(s) remains to be further defined. Deficiency of BRCA1 function leads to disrupted mitotic machinery and genomic instability. Here, we show that BRCA1 physically interacts and colocalizes with Nlp, an important molecule involved in centrosome maturation and spindle formation. Interestingly, Nlp centrosomal localization and its protein stability are regulated by normal cellular BRCA1 function because cells containing BRCA1 mutations or silenced for endogenous BRCA1 exhibit disrupted Nlp colocalization to centrosomes and enhanced Nlp degradation. Its is likely that the BRCA1 regulation of Nlp stability involves Plk1 suppression. Inhibition of endogenous Nlp via the small interfering RNA approach results in aberrant spindle formation, aborted chromosomal segregation, and aneuploidy, which mimic the phenotypes of disrupted BRCA1. Thus, BRCA1 interaction of Nlp might be required for the successful mitotic progression, and abnormalities of Nlp lead to genomic instability.

  2. Construction of a transcription map surrounding the BRCA1 locus of human chromosome 17

    SciTech Connect

    Brody, L.C.; Castilla, L.H.; McKinley, D.R.

    1995-01-01

    We have used a combination of methods to survey approximately 600 kb of genomic DNA surrounding the BRCA1 gene for transcribed sequences. We have cloned a set of fragments representing at least 26 genes. The DNA sequence of these clones reveals that 5 are previously cloned genes; the precise chromosomal location of 2 was previously unknown, and 3 have been cloned and mapped by others to this interval. Three other genes, including BRCA1 itself, have recently been mapped independently to this region. Sequences from 11 genes are similar but not identical matches to known genes; 5 of these appear to be the human homologues of genes cloned from other species. Another 7 genes have no similarity with known genes. In addition, 39 putative exons and 14 expressed sequence tags have been identified and mapped to individual cosmids. This transcript map provides a detailed description of gene organization for this region of the genome. 64 refs., 4 figs., 1 tab.

  3. Derepression of HMGA2 via Removal of ZBRK1/BRCA1/CtIP Complex Enhances Mammary Tumorigenesis*

    PubMed Central

    Ahmed, Kazi Mokim; Tsai, Connie Y.; Lee, Wen-Hwa

    2010-01-01

    The high mobility group AT-hook 2 (HMGA2), a DNA architectural protein, is highly regulated during development and plays an important role in tumorigenesis. Indeed, HMGA2 was overexpressed in many different kinds of tumors. However, the mechanisms regulating HMGA2 expression remain elusive. Using microarray analysis, we found that HMGA2, along with a dozen of other genes, was co-repressed by ZBRK1, BRCA1, and CtIP. BRCA1 exerts its transcriptional repression activity through interaction with the transcriptional repressor ZBRK1 in the central domain, and with CtIP in the C-terminal BRCT domain. Here, we show that ZBRK1, BRCA1, and CtIP form a repression complex that coordinately regulates HMGA2 expression via a ZBRK1 recognition site in the HMGA2 promoter. Depletion of any of the proteins in this complex via adenoviral RNA interference in MCF10A mammary epithelial cells activates HMGA2 expression, resulting in increased colony formation in soft agar. Similarly, depletion of ZBRK1, or ectopic overexpression of HMGA2, in MCF10A cells induces abnormal acinar size with increased cell number and inhibits normal acinar formation. Consistently, many BRCA1-deficient mouse breast tumors express higher levels of HMGA2 than BRCA1-proficient tumors. These results suggest that activation of HMGA2 gene expression through derepression of the ZBRK1/BRCA1/CtIP complex is a significant step in accelerating breast tumorigenesis. PMID:20007691

  4. BRCA1 regulates microRNA biogenesis via the DROSHA microprocessor complex.

    PubMed

    Kawai, Shinji; Amano, Atsuo

    2012-04-16

    MicroRNAs (miRNAs) are noncoding RNAs that function as key posttranscriptional regulators of gene expression. miRNA maturation is controlled by the DROSHA microprocessor complex. However, the detailed mechanism of miRNA biogenesis remains unclear. We show that the tumor suppressor breast cancer 1 (BRCA1) accelerates the processing of miRNA primary transcripts. BRCA1 increased the expressions of both precursor and mature forms of let-7a-1, miR-16-1, miR-145, and miR-34a. In addition, this tumor suppressor was shown to be directly associated with DROSHA and DDX5 of the DROSHA microprocessor complex, and it interacted with Smad3, p53, and DHX9 RNA helicase. We also found that BRCA1 recognizes the RNA secondary structure and directly binds with primary transcripts of miRNAs via a DNA-binding domain. Together, these results suggest that BRCA1 regulates miRNA biogenesis via the DROSHA microprocessor complex and Smad3/p53/DHX9. Our findings also indicate novel functions of BRCA1 in miRNA biogenesis, which may be linked to its tumor suppressor mechanism and maintenance of genomic stability.

  5. Genetic variants and haplotype analyses of the ZBRK1/ZNF350 gene in high-risk non BRCA1/2 French Canadian breast and ovarian cancer families.

    PubMed

    Desjardins, Sylvie; Belleau, Pascal; Labrie, Yvan; Ouellette, Geneviève; Bessette, Paul; Chiquette, Jocelyne; Laframboise, Rachel; Lépine, Jean; Lespérance, Bernard; Pichette, Roxane; Plante, Marie; Durocher, Francine

    2008-01-01

    Our current understanding of breast cancer susceptibility involves mutations in the 2 major genes BRCA1 and BRCA2, found in about 25% of high-risk families, as well as few other low penetrance genes such as ATM and CHEK2. Approximately two-thirds of the multiple cases families remain to be explained by mutations in still unknown genes. In a candidate gene approach to identify new genes potentially involved in breast cancer susceptibility, we analyzed genomic variants in the ZBRK1 gene, a co-repressor implicated in BRCA1-mediated repression of GADD45. Direct sequencing of ZBRK1 entire coding region in affected breast cancer individuals from 97 high-risk French Canadian breast/ovarian cancer families and 94 healthy controls led to the identification of 18 genomic variants. Haplotype analyses, using PHASE, COCAPHASE and HaploStats programs, put in evidence 3 specific haplotypes which could potentially modulate breast cancer risk, and among which 2 that are associated with a potential protective effect (p = 0.01135 and p = 0.00268), while another haplotype is over-represented in the case group (p = 0.00143). Further analyses of these haplotypes indicated that a strong component of the observed difference between both groups emerge from the first 5 variants (out of 12 used for haplotype determination). The present study also permitted to determine a set of tagging SNPs that could be useful for subsequent analyses in large scale association studies. Additional studies in large cohorts and other populations will however be needed to further evaluate if common and/or rare ZBRK1 sequence variants and haplotypes could be associated with a modest/intermediate breast cancer risk.

  6. 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.

  7. Effects of deletion and site-directed mutations on ligation steps of NAD+-dependent DNA ligase: a biochemical analysis of BRCA1 C-terminal domain.

    PubMed

    Feng, Hong; Parker, Jeremy M; Lu, Jing; Cao, Weiguo

    2004-10-01

    DNA strand joining entails three consecutive steps: enzyme adenylation to form AMP-ligase, substrate adenylation to form AMP-DNA, and nick closure. In this study, we investigate the effects on ligation steps by deletion and site-directed mutagenesis of the BRCA1 C-terminal (BRCT) domain using NAD(+)-dependent DNA ligase from Thermus species AK16D. Deletion of the BRCT domain resulted in substantial loss of ligation activity, but the mutant was still able to form an AMP-ligase intermediate, suggesting that the defects caused by deletion of the entire BRCT domain occur primarily at steps after enzyme adenylation. The lack of AMP-DNA accumulation by the domain deletion mutant as compared to the wild-type ligase indicates that the BRCT domain plays a role in the substrate adenylation step. Gel mobility shift analysis suggests that the BRCT domain and helix-hairpin-helix subdomain play a role in DNA binding. Similar to the BRCT domain deletion mutant, the G617I mutant showed a low ligation activity and lack of accumulation of AMP-DNA intermediate. However, the G617I mutant was only weakly adenylated, suggesting that a point mutation in the BRCT domain could also affect the enzyme adenylation step. The significant reduction of ligation activity by G634I appears to be attributable to a defect at the substrate adenylation step. The greater ligation of mismatched substrates by G638I is accountable by accelerated conversion of the AMP-DNA intermediate to a ligation product at the final nick closure step. The mutational effects of the BRCT domain on ligation steps in relation to protein-DNA and potential protein-protein interactions are discussed. PMID:15449954

  8. BRCA1185delAG tumors may acquire therapy resistance through expression of RING-less BRCA1

    PubMed Central

    Drost, Rinske; Dhillon, Kiranjit K.; van der Gulden, Hanneke; van der Heijden, Ingrid; Brandsma, Inger; Cruz, Cristina; Chondronasiou, Dafni; Castroviejo-Bermejo, Marta; van der Burg, Eline; Wientjens, Ellen; Pieterse, Mark; Klijn, Christiaan; Klarenbeek, Sjoerd; Loayza-Puch, Fabricio; Elkon, Ran; van Deemter, Liesbeth; Rottenberg, Sven; van de Ven, Marieke; Dekkers, Dick H.W.; Demmers, Jeroen A.A.; Agami, Reuven; Balmaña, Judith; Taniguchi, Toshiyasu; Bouwman, Peter

    2016-01-01

    Heterozygous germline mutations in breast cancer 1 (BRCA1) strongly predispose women to breast cancer. BRCA1 plays an important role in DNA double-strand break (DSB) repair via homologous recombination (HR), which is important for tumor suppression. Although BRCA1-deficient cells are highly sensitive to treatment with DSB-inducing agents through their HR deficiency (HRD), BRCA1-associated tumors display heterogeneous responses to platinum drugs and poly(ADP-ribose) polymerase (PARP) inhibitors in clinical trials. It is unclear whether all pathogenic BRCA1 mutations have similar effects on the response to therapy. Here, we have investigated mammary tumorigenesis and therapy sensitivity in mice carrying the Brca1185stop and Brca15382stop alleles, which respectively mimic the 2 most common BRCA1 founder mutations, BRCA1185delAG and BRCA15382insC. Both the Brca1185stop and Brca15382stop mutations predisposed animals to mammary tumors, but Brca1185stop tumors responded markedly worse to HRD-targeted therapy than did Brca15382stop tumors. Mice expressing Brca1185stop mutations also developed therapy resistance more rapidly than did mice expressing Brca15382stop. We determined that both murine Brca1185stop tumors and human BRCA1185delAG breast cancer cells expressed a really interesting new gene domain–less (RING-less) BRCA1 protein that mediated resistance to HRD-targeted therapies. Together, these results suggest that expression of RING-less BRCA1 may serve as a marker to predict poor response to DSB-inducing therapy in human cancer patients. PMID:27454287

  9. Germline mutations in the breast cancer susceptibility gene PTEN are rare in high-risk non-BRCA1/2 French Canadian breast cancer families.

    PubMed

    Guénard, Frédéric; Labrie, Yvan; Ouellette, Geneviève; Beauparlant, Charles Joly; Bessette, Paul; Chiquette, Jocelyne; Laframboise, Rachel; Lépine, Jean; Lespérance, Bernard; Pichette, Roxane; Plante, Marie; Durocher, Francine

    2007-01-01

    Cowden syndrome is a disease associated with an increase in breast cancer susceptibility. Alleles in PTEN and other breast cancer susceptibility genes would be responsible for approximately 25% of the familial component of breast cancer risk, BRCA1 and BRCA2 being the two major genes responsible for this inherited risk. In order to evaluate the proportion of high-risk French Canadian non-BRCA1/BRCA2 breast/ovarian cancer families potentially harboring a PTEN germline mutation, the whole coding and flanking intronic sequences were analyzed in a series of 98 breast cancer cases. Although no germline mutation has been identified in the coding region, our study led to the identification of four intronic variants. Further investigations were performed to analyze the effect of these variants, alone and/or in combination, on splicing and PTEN protein levels. Despite suggestive evidence emerging from in silico analyses, the presence of these intronic variants do not seem to alter RNA splicing or PTEN protein levels. In addition, as loss of PTEN or part of it has been reported, Western blot analysis has also been performed. No major deletion could be identified in our cohort. Therefore, assuming a Poisson distribution for the frequency of deleterious mutation in our cohort, if the frequency of such deleterious mutation was 2%, we would have had a 90% or greater chance of observing at least one such mutation. These results suggest that PTEN germline mutations are rare and are unlikely to account for a significant proportion of familial breast cancer cases in the French Canadian population.

  10. Preliminary crystallographic studies of BRCA1 BRCT–ABRAXAS complex

    PubMed Central

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

    2013-01-01

    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 P41212, 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

  11. Individual and Combined Expression of DNA Damage Response Molecules PARP1, γH2AX, BRCA1, and BRCA2 Predict Shorter Survival of Soft Tissue Sarcoma Patients

    PubMed Central

    Park, See-Hyoung; Park, Hye Jeong; Wang, Sung Il; Park, Ho Sung; Lee, Ho; Kwon, Keun Sang; Moon, Woo Sung; Lee, Dong Geun; Kim, Jung Ryul; Jang, Kyu Yun

    2016-01-01

    DNA damage response (DDR) molecules are protective against genotoxic stresses. DDR molecules are also involved in the survival of cancer cells in patients undergoing anti-cancer therapies. Therefore, DDR molecules are potential markers of cancer progression in addition to being potential therapeutic targets. In this study, we evaluated the immunohistochemical expression of PARP1, γH2AX, BRCA1, and BRCA2 and their prognostic significance in 112 cases of soft tissue sarcoma (STS). The expression of PARP1, γH2AX, BRCA1, and BRCA2 were significantly associated with each other and were associated with higher tumor stage and presence of distant metastasis. The expression of PARP1, γH2AX, and BRCA2 were significantly associated with shorter disease-specific survival (DSS) and event-free survival (EFS) by univariate analysis. BRCA1 expression was associated with shorter DSS. Multivariate analysis revealed the expression of PARP1 and γH2AX to be independent indicators of poor prognosis of DSS and EFS. BRCA2 expression was an independent indicator of poor prognosis of DSS. In addition, the combined expressional patterns of PARP1, γH2AX, BRCA1, and BRCA2 (CSddrm) were independent prognostic predictors of DSS (P < 0.001) and EFS (P = 0.016). The ten-year DSS rate of the CSddrm-low, CSddrm-intermediate, and CSddrm-high subgroups were 81%, 26%, and 0%, respectively. In conclusion, this study demonstrates that the individual and combined expression patterns of the DDR molecules PARP1, γH2AX, BRCA1, and BRCA2 could be predictive of the prognosis of STS patients and suggests that controlling the activity of these DDR molecules could be employed in new therapeutic stratagems for the treatment of STS. PMID:27643881

  12. Individual and Combined Expression of DNA Damage Response Molecules PARP1, γH2AX, BRCA1, and BRCA2 Predict Shorter Survival of Soft Tissue Sarcoma Patients.

    PubMed

    Kim, Kyoung Min; Moon, Young Jae; Park, See-Hyoung; Park, Hye Jeong; Wang, Sung Il; Park, Ho Sung; Lee, Ho; Kwon, Keun Sang; Moon, Woo Sung; Lee, Dong Geun; Kim, Jung Ryul; Jang, Kyu Yun

    2016-01-01

    DNA damage response (DDR) molecules are protective against genotoxic stresses. DDR molecules are also involved in the survival of cancer cells in patients undergoing anti-cancer therapies. Therefore, DDR molecules are potential markers of cancer progression in addition to being potential therapeutic targets. In this study, we evaluated the immunohistochemical expression of PARP1, γH2AX, BRCA1, and BRCA2 and their prognostic significance in 112 cases of soft tissue sarcoma (STS). The expression of PARP1, γH2AX, BRCA1, and BRCA2 were significantly associated with each other and were associated with higher tumor stage and presence of distant metastasis. The expression of PARP1, γH2AX, and BRCA2 were significantly associated with shorter disease-specific survival (DSS) and event-free survival (EFS) by univariate analysis. BRCA1 expression was associated with shorter DSS. Multivariate analysis revealed the expression of PARP1 and γH2AX to be independent indicators of poor prognosis of DSS and EFS. BRCA2 expression was an independent indicator of poor prognosis of DSS. In addition, the combined expressional patterns of PARP1, γH2AX, BRCA1, and BRCA2 (CSddrm) were independent prognostic predictors of DSS (P < 0.001) and EFS (P = 0.016). The ten-year DSS rate of the CSddrm-low, CSddrm-intermediate, and CSddrm-high subgroups were 81%, 26%, and 0%, respectively. In conclusion, this study demonstrates that the individual and combined expression patterns of the DDR molecules PARP1, γH2AX, BRCA1, and BRCA2 could be predictive of the prognosis of STS patients and suggests that controlling the activity of these DDR molecules could be employed in new therapeutic stratagems for the treatment of STS. PMID:27643881

  13. 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

  14. 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

  15. 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.

  16. 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

  17. 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.

  18. A radiation hybrid map of the BRCA1 region

    SciTech Connect

    O'Connell, P.; Taylor, T.; Hundley, J.E.; Johnson-Pais, T.L.; Reus, B.; Leach, R.J. )

    1994-03-01

    A locus on chromosome 17q, designated BRCA1', has been identified as a predisposition gene for breast cancer. A panel of chromosome 17-specific radiation-reduced somatic cell hybrid clones has been assembled for high-resolution mapping of chromosome 17. A series of 35 markers, known to span the BRCA1 locus, were tested against this hybrid panel by PCR assays. Statistical analysis of these data yields a BRCA1 radiation hybrid map at a density sufficient to initiate YAC cloning and pulsed-field gel electrophoretic mapping of the candidate regional In addition, many of the markers reveal genetic polymorphisms and may be tested in breast cancer families and in loss-of-heterozygosity studies of sporadic breast cancers to better define the BRCA1 gene candidate region. 33 refs., 1 fig., 2 tabs.

  19. 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

  20. BP1, an Isoform of DLX4 Homeoprotein, Negatively Regulates BRCA1 in Sporadic Breast Cancer

    PubMed Central

    Kluk, Brian J.; Fu, Yebo; Formolo, Trina A.; Zhang, Lei; Hindle, Anne K.; Man, Yan-gao; Siegel, Robert S.; Berg, Patricia E.; Deng, Chuxia; McCaffrey, Timothy A.; Fu, Sidney W.

    2010-01-01

    Introduction: Several lines of evidence point to an important role for BP1, an isoform of DLX4 homeobox gene, in breast carcinogenesis and progression. BRCA1 is a well-known player in the etiology of breast cancer. While familial breast cancer is often marked by BRCA1 mutation and subsequent loss of heterozygosity, sporadic breast cancers exhibit reduced expression of wild type BRCA1, and loss of BRCA1 expression may result in tumor development and progression. Methods: The Cister algorithm and Genomatix program were used to identify potential BP1 binding sites in BRCA1 gene. Real-time PCR, Western blot and immunohistochemistry analysis were performed to verify the expression of BRCA1 and BP1 in cell lines and breast cancer tissues. Double-stranded siRNA transfection was carried out for silencing BP1 expression. ChIP and EMSA were used to confirm that BP1 specifically binds to BRCA1. Results: A putative BP1 binding site was identified in the first intron of BRCA1, which was confirmed by chromatin immunoprecipiation and electrophoresis mobility shift assay. BP1 and BRCA1 expression were inversely correlated in breast cancer cell lines and tissues, suggesting that BP1 may suppress BRCA1 transcription through consensus sequence binding. Conclusions: BP1 homeoprotein represses BRCA1 expression through direct binding to its first intron, which is consistent with a previous study which identified a novel transcriptional repressor element located more than 500 base pairs into the first intron of BRCA1, suggesting that the first intron plays an important role in the negative regulation of BRCA1. Although further functional studies are necessary to confirm its repressor activity towards BRCA1, the elucidation of the role of BP1 in breast tumorigenesis holds great promise in establishing BP1 as a novel target for drug therapy. PMID:20877436

  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. Mouse Brca1: localization sequence analysis and identification of evolutionarily conserved domains.

    PubMed

    Abel, K J; Xu, J; Yin, G Y; Lyons, R H; Meisler, M H; Weber, B L

    1995-12-01

    The human genes BRCA1, conferring susceptibility to early-onset breast and ovarian cancer, has recently been isolated. Here we describe isolation of cDNAs, sequence analysis, and genomic localization of the murine homolog, Brac1. The mouse cDNA sequence predicts a protein of 1812 amino acids; a number of small gaps account for the 51 fewer residues in the mouse protein relative to human BRCA1. While the predicted mouse and human proteins display on the whole a high level of homology (58% identity, 73% similarity), the regions of greatest homology are at the respective amino and carboxyl termini. Most reported disease-associated missense mutations in human BCRA1 occurred within these more highly conserved terminal regions. A predicted zinc-building RING finger domain near the amino terminus lies within a 50 amino acid stretch that is perfectly conserved in both species. The strong conservation during mammalian evolution argues for the importance of this domain, perhaps mediating a role for BRCA1 in DNA and/or protein binding. We have also identified a conserved highly acidic domain in the carboxyl terminal half of the BCRA1 protein resembling acidic transactivation domains of certain transcription factors. Using an interspecific backcross panel, Brca1 was mapped to a region of mouse chromosome 11 that exhibits conserved linkage with 17q21. The sequence and isolated cDNAs will provide useful reagents for studying the expression of Brca1 in the mouse, and for testing the importance of the evolutionarily conserved domains.

  3. Next-generation sequencing meets genetic diagnostics: development of a comprehensive workflow for the analysis of BRCA1 and BRCA2 genes

    PubMed Central

    Feliubadaló, Lídia; Lopez-Doriga, Adriana; Castellsagué, Ester; del Valle, Jesús; Menéndez, Mireia; Tornero, Eva; Montes, Eva; Cuesta, Raquel; Gómez, Carolina; Campos, Olga; Pineda, Marta; González, Sara; Moreno, Victor; Brunet, Joan; Blanco, Ignacio; Serra, Eduard; Capellá, Gabriel; Lázaro, Conxi

    2013-01-01

    Next-generation sequencing (NGS) is changing genetic diagnosis due to its huge sequencing capacity and cost-effectiveness. The aim of this study was to develop an NGS-based workflow for routine diagnostics for hereditary breast and ovarian cancer syndrome (HBOCS), to improve genetic testing for BRCA1 and BRCA2. A NGS-based workflow was designed using BRCA MASTR kit amplicon libraries followed by GS Junior pyrosequencing. Data analysis combined Variant Identification Pipeline freely available software and ad hoc R scripts, including a cascade of filters to generate coverage and variant calling reports. A BRCA homopolymer assay was performed in parallel. A research scheme was designed in two parts. A Training Set of 28 DNA samples containing 23 unique pathogenic mutations and 213 other variants (33 unique) was used. The workflow was validated in a set of 14 samples from HBOCS families in parallel with the current diagnostic workflow (Validation Set). The NGS-based workflow developed permitted the identification of all pathogenic mutations and genetic variants, including those located in or close to homopolymers. The use of NGS for detecting copy-number alterations was also investigated. The workflow meets the sensitivity and specificity requirements for the genetic diagnosis of HBOCS and improves on the cost-effectiveness of current approaches. PMID:23249957

  4. BRCA1 protein level is not affected by peptide growth factors in MCF10A cell line.

    PubMed

    Aprelikova, O; Kuthiala, A; Bessho, M; Ethier, S; Liu, E T

    1996-12-01

    The breast cancer susceptibility gene (BRCA1) has been identified as a putative tumor suppressor on chromosome 17. We raised antibody against Ring-finger domain of BRCA1. The antibody recognizes a specific BRCA1 protein doublet of about 220 kD. The majority of BRCA1 protein is localized to the nuclear fraction of untreated MCF10A cells. Though BRCA1 is thought to be a growth suppressor gene, no change in BRCA1 protein level was found when MCF10A cells were arrested by growth factor deprivation or stimulation of cell proliferation by re-addition of growth factors. Furthermore the subcellular localization of the BRCA1 protein does not change throughout the cell cycle. These results suggest that BRCA1 may not be directly involved in the regulation of the cell cycle of breast cancer cell line.

  5. Comparison of techniques for the successful detection of BRCA1 mutations in fixed paraffin-embedded tissue.

    PubMed

    Bernstein, Jonine L; Thompson, W Douglas; Casey, Graham; DiCioccio, Richard A; Whittemore, Alice S; Diep, Anh T; Thakore, Seema S; Vaziri, Susan; Xue, Shanyan; Haile, Robert W

    2002-09-01

    Genomic DNA isolated from archived paraffin-embedded tissues (PETs) has important applicability in genetic epidemiological studies. To determine the accuracy of the sequence data, using DNA derived from PET among patients with known mutations characterized from blood, we conducted a blinded factorial experiment to simultaneously examine the influence of mutation type, age of the PET, PCR product type, and Taq DNA polymerase on BRCA1 gene mutation detection. The probability of detecting sequencing artifacts was also investigated. We found that: (a) gene detection was most accurate for newer PET; (b) high fidelity Taq with shorter PCR amplicon length yielded the highest mutation detection success rate and lowest artifact rate; and (c) base substitutions were more often correctly identified than frameshift mutations or wild-type sequences. We concluded that DNA derived from PET that archived for less than 18 years can be used successfully for detecting BRCA1 gene mutations if quality control is strictly maintained.

  6. Promoter mutation and reduced expression of BRCA1 in canine mammary tumors.

    PubMed

    Qiu, H B; Sun, W D; Yang, X; Jiang, Q Y; Chen, S; Lin, D G

    2015-12-01

    Breast cancer 1, early onset (BRCA1) is one of the most important genes in human familial breast cancer, which also plays an important role in canine mammary tumors. The objectives of this study were to determine the promoter sequence of canine BRCA1, to investigate its promoter mutation status and to describe BRCA1 expression pattern in canine mammary tumors. The promoter sequence of canine BRCA1 was acquired by aligning human BRCA1 promoter sequence with canine genomic sequence and confirmed by standard promoter activity analysis. Same as human BRCA1 promoter, the CAAT box and G/C box were found in canine BRCA1 promoter. In order to explore the mutation status of the promoter region and to investigate the expression pattern of this gene, 10 normal canine mammary tissues, 15 benign mammary tumors and 15 malignant mammary tumors were used. By sequencing, 46.7% of the malignant mammary tumors were found with a deletion of one cytosine in the promoter region. The mRNA expression of BRCA1 was significantly reduced in benign and malignant mammary tumors (P<0.05), and the protein expression of BRCA1 was significantly reduced in malignant mammary tumors (P<0.05). This study is the first time to determine the canine BRCA1 promoter sequence and to describe the promoter mutation status in canine mammary tumors. PMID:26679809

  7. Large genomic rearrangements in the familial breast and ovarian cancer gene BRCA1 are associated with an increased frequency of high risk features.

    PubMed

    James, Paul A; Sawyer, Sarah; Boyle, Samantha; Young, Mary-Anne; Kovalenko, Serguei; Doherty, Rebecca; McKinley, Joanne; Alsop, Kathryn; Beshay, Victoria; Harris, Marion; Fox, Stephen; Lindeman, Geoffrey J; Mitchell, Gillian

    2015-06-01

    Large genomic rearrangements (LGRs) account for at least 10% of the mutations in BRCA1 and 5% of BRCA2 mutations in outbred hereditary breast and ovarian cancer (HBOC) families. Data from some series suggest LGRs represent particularly penetrant mutations. 1,034 index cases from HBOC families underwent comprehensive BRCA1 and BRCA2 mutation testing, including screening for LGRs. The personal and family history of 254 identified mutation carriers were compared based on mutation type. Thirty-six LGRs were detected; 32/122 (26%) BRCA1 and 4/132 (3%) BRCA2 mutations. High risk features (bilateral breast cancer, diagnosis <40 years, ovarian cancer, male breast cancer) were more commonly associated with an LGR than a non-LGR mutation (p = 0.008), In families with a BRCA1 LGR the mean age of breast cancer diagnosis was younger than in families with a non-LGR BRCA1 mutation (42.5 vs. 46.1 years, p = 0.007). Across the entire group of mutation positive families the number of relatives affected by breast or ovarian cancer was increased [LGR 3.7 vs. non- LGR 2.8 per family, p value (adjusted for genotype) = 0.047]. Excluding index cases, the odds ratio for breast cancer in BRCA1 families with an LGR was 1.42 (95% CI 1.24-1.63) and for ovarian cancer 1.66 (95% CI 1.10-2.49). The increased cancer risk was reflected in significantly higher risk assessments by mutation prediction tools. LGRs are associated with higher cancer risks. If validated, LGRs could be included in cancer risk prediction tools to improve personalised cancer risk prediction estimates and may guide cost-minimising mutation screening strategies in some healthcare settings.

  8. 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.

  9. 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}.

  10. 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.

  11. 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.

  12. The role of germline mutations in the BRCA1/2 and mismatch repair genes in men ascertained for early-onset and/or familial prostate cancer.

    PubMed

    Maia, Sofia; Cardoso, Marta; Paulo, Paula; Pinheiro, Manuela; Pinto, Pedro; Santos, Catarina; Pinto, Carla; Peixoto, Ana; Henrique, Rui; Teixeira, Manuel R

    2016-01-01

    Prostate cancer (PrCa) is one of the most common cancers diagnosed worldwide and 5-10 % of all cases are estimated to be associated with inherited predisposition. Even though there is strong evidence that the genetic component is significant in PrCa, the genetic etiology of familial and early-onset disease is largely unknown. Although it has been suggested that men from families with hereditary breast/ovarian cancer (HBOC) and, more recently, with Lynch syndrome may have an increased risk for PrCa, the contribution of these syndromes to PrCa predisposition in families ascertained for early-onset and/or familial PrCa, independently of the presence of other cancers in the family, is uncertain. To quantify the contribution of genes associated with HBOC and Lynch syndromes to PrCa predisposition, we have tested for germline mutations 460 early-onset and/or familial PrCa patients. All patients were screened for the six mutations that are particularly common in Portugal and 38 of them were selected for complete sequencing of BRCA1/2 and/or MLH1, MSH2 and MSH6. Two patients were found to harbor the same MSH2 mutation and a third patient carried a Portuguese BRCA2 founder mutation. None of the alterations were identified in 288 control subjects. Furthermore, we reviewed the 62 PrCa diagnoses in all HBOC (n = 161) and Lynch syndrome (n = 124) families previously diagnosed at our department, and found five other BRCA2 mutation carriers and two additional MSH2 mutation carriers. The clinicopathological characteristics of mutation carriers are in concordance with earlier data suggesting an aggressive PrCa phenotype and support the hypothesis that mutation carriers might benefit from targeted screening according to the gene mutated in the germline.

  13. A subset of ATM- and ATR-dependent phosphorylation events requires the BRCA1 protein

    PubMed Central

    Foray, Nicolas; Marot, Didier; Gabriel, Anastasia; Randrianarison, Voahangy; Carr, Antony M.; Perricaudet, Michel; Ashworth, Alan; Jeggo, Penny

    2003-01-01

    BRCA1 is a central component of the DNA damage response mechanism and defects in BRCA1 confer sensitivity to a broad range of DNA damaging agents. BRCA1 is required for homologous recombination and DNA damage-induced S and G2/M phase arrest. We show here that BRCA1 is required for ATM- and ATR-dependent phosphorylation of p53, c-Jun, Nbs1 and Chk2 following exposure to ionizing or ultraviolet radiation, respectively, and is also required for ATM phosphorylation of CtIP. In contrast, DNA damage-induced phosphorylation of the histone variant H2AX is independent of BRCA1. We also show that the presence of BRCA1 is dispensable for DNA damage-induced phosphorylation of Rad9, Hus1 and Rad17, and for the relocalization of Rad9 and Hus1. We propose that BRCA1 facilitates the ability of ATM and ATR to phosphorylate downstream substrates that directly influence cell cycle checkpoint arrest and apoptosis, but that BRCA1 is dispensable for the phosphorylation of DNA-associated ATM and ATR substrates. PMID:12773400

  14. 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

  15. Stabilization of mutant BRCA1 protein confers PARP inhibitor and platinum resistance

    PubMed Central

    Johnson, Neil; Johnson, Shawn F.; Yao, Wei; Li, Yu-Chen; Choi, Young-Eun; Bernhardy, Andrea J.; Wang, Yifan; Capelletti, Marzia; Sarosiek, Kristopher A.; Moreau, Lisa A.; Chowdhury, Dipanjan; Wickramanayake, Anneka; Harrell, Maria I.; Liu, Joyce F.; D’Andrea, Alan D.; Miron, Alexander; Swisher, Elizabeth M.; Shapiro, Geoffrey I.

    2013-01-01

    Breast Cancer Type 1 Susceptibility Protein (BRCA1)-deficient cells have compromised DNA repair and are sensitive to poly(ADP-ribose) polymerase (PARP) inhibitors. Despite initial responses, the development of resistance limits clinical efficacy. Mutations in the BRCA C-terminal (BRCT) domain of BRCA1 frequently create protein products unable to fold that are subject to protease-mediated degradation. Here, we show HSP90-mediated stabilization of a BRCT domain mutant BRCA1 protein under PARP inhibitor selection pressure. The stabilized mutant BRCA1 protein interacted with PALB2-BRCA2-RAD51, was essential for RAD51 focus formation, and conferred PARP inhibitor as well as cisplatin resistance. Treatment of resistant cells with the HSP90 inhibitor 17-dimethylaminoethylamino-17-demethoxygeldanamycin reduced mutant BRCA1 protein levels and restored their sensitivity to PARP inhibition. Resistant cells also acquired a TP53BP1 mutation that facilitated DNA end resection in the absence of a BRCA1 protein capable of binding CtIP. Finally, concomitant increased mutant BRCA1 and decreased 53BP1 protein expression occur in clinical samples of BRCA1-mutated recurrent ovarian carcinomas that have developed resistance to platinum. These results provide evidence for a two-event mechanism by which BRCA1-mutant tumors acquire anticancer therapy resistance. PMID:24085845

  16. Homologous recombination and human health: the roles of BRCA1, BRCA2, and associated proteins.

    PubMed

    Prakash, Rohit; Zhang, Yu; Feng, Weiran; Jasin, Maria

    2015-04-01

    Homologous recombination (HR) is a major pathway for the repair of DNA double-strand breaks in mammalian cells, the defining step of which is homologous strand exchange directed by the RAD51 protein. The physiological importance of HR is underscored by the observation of genomic instability in HR-deficient cells and, importantly, the association of cancer predisposition and developmental defects with mutations in HR genes. The tumor suppressors BRCA1 and BRCA2, key players at different stages of HR, are frequently mutated in familial breast and ovarian cancers. Other HR proteins, including PALB2 and RAD51 paralogs, have also been identified as tumor suppressors. This review summarizes recent findings on BRCA1, BRCA2, and associated proteins involved in human disease with an emphasis on their molecular roles and interactions. PMID:25833843

  17. 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

  18. Massively Parallel Functional Analysis of BRCA1 RING Domain Variants

    PubMed Central

    Starita, Lea M.; Young, David L.; Islam, Muhtadi; Kitzman, Jacob O.; Gullingsrud, Justin; Hause, Ronald J.; Fowler, Douglas M.; Parvin, Jeffrey D.; Shendure, Jay; Fields, Stanley

    2015-01-01

    Interpreting variants of uncertain significance (VUS) is a central challenge in medical genetics. One approach is to experimentally measure the functional consequences of VUS, but to date this approach has been post hoc and low throughput. Here we use massively parallel assays to measure the effects of nearly 2000 missense substitutions in the RING domain of BRCA1 on its E3 ubiquitin ligase activity and its binding to the BARD1 RING domain. From the resulting scores, we generate a model to predict the capacities of full-length BRCA1 variants to support homology-directed DNA repair, the essential role of BRCA1 in tumor suppression, and show that it outperforms widely used biological-effect prediction algorithms. We envision that massively parallel functional assays may facilitate the prospective interpretation of variants observed in clinical sequencing. PMID:25823446

  19. BRCA1/2 genetic background-based therapeutic tailoring of human ovarian cancer: hope or reality?

    PubMed Central

    Tagliaferri, Pierosandro; Ventura, Monica; Baudi, Francesco; Cucinotto, Iole; Arbitrio, Mariamena; Di Martino, Maria Teresa; Tassone, Pierfrancesco

    2009-01-01

    Ovarian epithelial tumors are an hallmark of hereditary cancer syndromes which are related to the germ-line inheritance of cancer predisposing mutations in BRCA1 and BRCA2 genes. Although these genes have been associated with multiple different physiologic functions, they share an important role in DNA repair mechanisms and therefore in the whole genomic integrity control. These findings have risen a variety of issues in terms of treatment and prevention of breast and ovarian tumors arising in this context. Enhanced sensitivity to platinum-based anticancer drugs has been related to BRCA1/2 functional loss. Retrospective studies disclosed differential chemosensitivity profiles of BRCA1/2-related as compared to "sporadic" ovarian cancer and led to the identification of a "BRCA-ness" phenotype of ovarian cancer, which includes inherited BRCA1/2 germ-line mutations, a serous high grade histology highly sensitive to platinum derivatives. Molecularly-based tailored treatments of human tumors are an emerging issue in the "era" of molecular targeted drugs and molecular profiling technologies. We will critically discuss if the genetic background of ovarian cancer can indeed represent a determinant issue for decision making in the treatment selection and how the provocative preclinical findings might be translated in the therapeutic scenario. The presently available preclinical and clinical evidence clearly indicates that genetic background has an emerging role in treatment individualization for ovarian cancer patients. PMID:19825178

  20. Murine Brca1: sequence and significance for human missense mutations.

    PubMed

    Sharan, S K; Wims, M; Bradley, A

    1995-12-01

    We have cloned and sequenced a mouse homologue of the human breast and ovarian cancer susceptibility gene, BRCA1. The predicted mouse Brca1 protein is composed of 1812 amino acids. The murine protein is 60% identical and 72% similar to the human BRCA1 protein. Two regions of high homology have been identified between the two proteins. First is the Cys3-His-Cys4 type zinc-finger domain that is identical between the two proteins. The second region is defined by 115 amino acids near the carboxyl end of the Brca1 protein that is 83% identical to human BRCA1 sequence. Seven of eight amino acids involved in human missense mutations that are associated with the disease were found to be conserved between the two species. In contrast, most of the amino acids that are involved in polymorphic variations were not conserved. We therefore propose that the interspecies conservation of predicted amino acid sequences can be used as an additional criterion to determine the significance of human missense mutations.

  1. Characterization of direct selected cDNAs from the BRCA1 region of 17q21

    SciTech Connect

    Welcsh, P.L.; Osborne-Lawrence, S.L.; Spillman, M.A.

    1994-09-01

    A gene involved in the development of early-onset familial breast and ovarian cancer, BRCA1, has been mapped to human chromosome 17q21. Polymorphisms closely linked to BRCA1 has been sublocalized to a region of 17q21 which is defined by the markers D17S856 and D17S78. A physical map of this region, that consists of yeast artificial chromosome (YAC) and cosmid contigs, has been constructed and used to isolate potential coding sequences via direct selection. We have identified at least 23 unique transcripts in a 600 kb interval corresponding to approximately one gene every 30 kb. We have determined the expression profile of these cDNAs by generating cDNA-specific primers which have been used in a screen of cDNAs derived from wide variety of tissues and cell types. Full length cDNA clones are being obtained from cDNA libraries in which the genes have been shown to be expressed by a variety of techniques which include direct screening, 5{prime} and 3{prime} RACE, anchor PCR as well as modified selection procedures. We are currently screening for mutations in these candidate cDNAs in affected family members known to harbor a germ-line BRCA1 mutation and in sporadic breast and ovarian tumors. Mutation screening is being performed by Southern and Northern blotting, DNA sequencing, and SSCP analysis of germline DNA and cDNA. Finally, we are analyzing these candidate cDNAs in a number of breast and ovarian cancer cell lines for induction by known mitogenic factors such as estrogen and progesterone by Northern blotting and RT-PCR.

  2. 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

  3. BRCA1-mutated and basal-like breast cancers have similar aCGH profiles and a high incidence of protein truncating TP53 mutations

    PubMed Central

    2010-01-01

    Background Basal-like breast cancers (BLBC) are aggressive breast cancers for which, so far, no targeted therapy is available because they typically lack expression of hormone receptors and HER2. Phenotypic features of BLBCs, such as clinical presentation and early age of onset, resemble those of breast tumors from BRCA1-mutation carriers. The genomic instability of BRCA1-mutated tumors can be effectively targeted with DNA-damaging agents and poly-(ADP-ribose) polymerase 1 (PARP1) inhibitors. Molecular similarities between BLBCs and BRCA1-mutated tumors may therefore provide predictive markers for therapeutic response of BLBCs. Methods There are several known molecular features characteristic for BRCA1-mutated breast tumors: 1) increased numbers of genomic aberrations, 2) a distinct pattern of genomic aberrations, 3) a high frequency of TP53 mutations and 4) a high incidence of complex, protein-truncating TP53 mutations. We compared the frequency of TP53 mutations and the pattern and amount of genomic aberrations between BRCA1-mutated breast tumors, BLBCs and luminal breast tumors by TP53 gene sequencing and array-based comparative genomics hybridization (aCGH) analysis. Results We found that the high incidence of protein truncating TP53 mutations and the pattern and amount of genomic aberrations specific for BRCA1-mutated breast tumors are also characteristic for BLBCs and different from luminal breast tumors. Conclusions Complex, protein truncating TP53 mutations in BRCA1-mutated tumors may be a direct consequence of genomic instability caused by BRCA1 loss, therefore, the presence of these types of TP53 mutations in sporadic BLBCs might be a hallmark of BRCAness and a potential biomarker for sensitivity to PARP inhibition. Also, our data suggest that a small subset of genomic regions may be used to identify BRCA1-like BLBCs. BLBCs share molecular features that were previously found to be specific for BRCA1-mutated breast tumors. These features might be useful

  4. 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

  5. BRCA1 founder mutations compared to ovarian cancer in Belarus.

    PubMed

    Savanevich, Alena; Oszurek, Oleg; Lubiński, Jan; Cybulski, Cezary; Dębniak, Tadeusz; Narod, Steven A; Gronwald, Jacek

    2014-09-01

    In Belarus and other Slavic countries, founder mutations in the BRCA1 gene are responsible for a significant proportion of breast cancer cases, but the data on contribution of these mutations to ovarian cancers are limited. To estimate the proportion of ovarian cancers in Belarus, which are dependent on BRCA1 Slavic founder mutations, we sought the presence of three most frequent mutations (BRCA1: 5382insC, C61G and, 4153delA) in 158 consecutive unselected cases of ovarian cancer. One of the three founder mutations was present in 25 of 158 unselected cases of ovarian cancer (15.8 %). We recommend that all cases of ovarian cancer in Belarus be offered genetic testing for these founder mutations. Furthermore, genetic testing of the Belarusian population will provide the opportunity to prevent a significant proportion of ovarian cancer.

  6. BRCA1 mutations in southern England.

    PubMed Central

    Eccles, D. M.; Englefield, P.; Soulby, M. A.; Campbell, I. G.

    1998-01-01

    If genetic testing for breast and ovarian cancer predisposition is to become available within a public health care system there needs to be a rational and cost-effective approach to mutation analysis. We have screened for BRCA1 mutations in 230 women with breast cancer, all from the Wessex region of southern England, in order to establish the parameters on which to base a cost-effective regional mutation analysis strategy. Truncating mutations were detected in 10/155 (6.5%) consecutive cases selected only for diagnosis under the age of 40 (nine of these ten women had a strong family history of breast or ovarian cancer), 3/61 (4.9%) bilateral-breast cancer cases (all three mutations occurring among women for whom the first cancer was diagnosed under 40 years) and 8/30 (26.6%) breast cancer cases presenting to the genetics clinic (for whom a strong family history of breast and/or ovarian cancer was present). Ten different mutations were detected in 17 families, but three of these accounted for 10/17 (59%) of the families. The cost of screening the population for mutations in the entire BRCA1 gene is unacceptably high. However, the cost of screening a carefully selected patient cohort is low, the risk of misinterpretation much less and the potential clinical benefits clearer. PMID:9649133

  7. 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.

  8. Genetic heterogeneity in hereditary breast cancer: Role of BRCA1 and BRCA2

    SciTech Connect

    Rebbeck, T.R.; Couch, F.J.; Kant, J.

    1996-09-01

    The common hereditary forms of breast cancer have been largely attributed to the inheritance of mutations in the BRCA1 or BRCA2 genes. However, it is not yet clear what proportion of hereditary breast cancer is explained by BRCA1 and BRCA2 or by some other unidentified susceptibility gene(s). We describe the proportion of hereditary breast cancer explained by BRCA1 or BRCA2 in a sample of North American hereditary breast cancers and assess the evidence for additional susceptibility genes that may confer hereditary breast or ovarian cancer risk. Twenty-three families were identified through two high-risk breast cancer research programs. Genetic analysis was undertaken to establish linkage between the breast or ovarian cancer cases and markers on chromosomes 17q (BRCA1) and 13q (BRCA2). Mutation analysis in the BRCA1 and BRCA2 genes was also undertaken in all families. The pattern of hereditary cancer in 14 (61%) of the 23 families studied was attributed to BRCA1 by a combination of linkage and mutation analyses. No families were attributed to BRCA2. Five families (22%) provided evidence against linkage to both BRCA1 and BRCA2. No BRCA1 or BRCA2 mutations were detected in these five families. The BRCA1 or BRCA2 status of four families (17%) could not be determined. BRCA1 and BRCA2 probably explain the majority of hereditary breast cancer that exists in the North American population. However, one or more additional genes may yet be found that explain some proportion of hereditary breast cancer. 19 refs., 1 fig., 3 tabs.

  9. RING domain-deficient BRCA1 promotes PARP inhibitor and platinum resistance.

    PubMed

    Wang, Yifan; Krais, John J; Bernhardy, Andrea J; Nicolas, Emmanuelle; Cai, Kathy Q; Harrell, Maria I; Kim, Hyoung H; George, Erin; Swisher, Elizabeth M; Simpkins, Fiona; Johnson, Neil

    2016-08-01

    Patients with cancers that harbor breast cancer 1 (BRCA1) mutations initially respond well to platinum and poly(ADP-ribose) polymerase inhibitor (PARPi) therapy; however, resistance invariably arises in these patients and is a major clinical problem. The BRCA1185delAG allele is a common inherited mutation located close to the protein translation start site that is thought to produce a shortened, nonfunctional peptide. In this study, we investigated the mechanisms that lead to PARPi and platinum resistance in the SUM1315MO2 breast cancer cell line, which harbors a hemizygous BRCA1185delAG mutation. SUM1315MO2 cells were initially sensitive to PARPi and cisplatin but readily acquired resistance. PARPi- and cisplatin-resistant clones did not harbor secondary reversion mutations; rather, PARPi and platinum resistance required increased expression of a really interesting gene (RING) domain-deficient BRCA1 protein (Rdd-BRCA1). Initiation of translation occurred downstream of the frameshift mutation, probably at the BRCA1-Met-297 codon. In contrast to full-length BRCA1, Rdd-BRCA1 did not require BRCA1-associated RING domain 1 (BARD1) interaction for stability. Functionally, Rdd-BRCA1 formed irradiation-induced foci and supported RAD51 foci formation. Ectopic overexpression of Rdd-BRCA1 promoted partial PARPi and cisplatin resistance. Furthermore, Rdd-BRCA1 protein expression was detected in recurrent carcinomas from patients who carried germline BRCA1185delAG mutations. Taken together, these results indicate that RING-deficient BRCA1 proteins are hypomorphic and capable of contributing to PARPi and platinum resistance when expressed at high levels. PMID:27454289

  10. Large family with both parents affected by distinct BRCA1 mutations: implications for genetic testing

    PubMed Central

    Sokolenko, Anna P; Voskresenskiy, Dmitry A; Iyevleva, Aglaya G; Bit-Sava, Elena M; Gutkina, Nadezhda I; Anisimenko, Maxim S; Yu Sherina, Nathalia; Mitiushkina, Nathalia V; Ulibina, Yulia M; Yatsuk, Olga S; Zaitseva, Olga A; Suspitsin, Evgeny N; Togo, Alexandr V; Pospelov, Valery A; Kovalenko, Sergey P; Semiglazov, Vladimir F; Imyanitov, Evgeny N

    2009-01-01

    Although the probability of both parents being affected by BRCA1 mutations is not negligible, such families have not been systematically described in the literature. Here we present a large breast-ovarian cancer family, where 3 sisters and 1 half-sister inherited maternal BRCA1 5382insC mutation while the remaining 2 sisters carried paternal BRCA1 1629delC allele. No BRCA1 homozygous mutations has been detected, that is consistent with the data on lethality of BRCA1 knockout mice. This report exemplifies that the identification of a single cancer-predisposing mutation within the index patient may not be sufficient in some circumstances. Ideally, all family members affected by breast or ovarian tumor disease have to be subjected to the DNA testing, and failure to detect the mutation in any of them calls for the search of the second cancer-associated allele. PMID:19338681

  11. BRCA1-Associated Triple-Negative Breast Cancer and Potential Treatment for Ruthenium-Based Compounds.

    PubMed

    Hongthong, Khwanjira; Ratanaphan, Adisorn

    2016-01-01

    Triple-negative breast cancer (TNBC) is defined by the absence of expression of estrogen receptor (ER), progesterone receptor (PR), and a lack of overexpression or amplification of human epidermal growth factor receptor 2 (HER2). The clinicopathological characteristics of TNBC include a high grading, a high rate of cell proliferation and a greater degree of chromosomal rearrangement. Patients with triple-negative breast cancer are more likely to be drug resistant and more difficult to treat, and are also frequently BRCA1 mutants. Methylation of the BRCA1 promoter region is associated with a reduction of the BRCA1 mRNA level. TNBC patients with a methylated BRCA1 had a better disease-free survival compared with those with non-methylated BRCA1. From a therapeutic perspective, the expression level of BRCA1 has been a major determinant of the responses to different classes of chemotherapy. BRCA1-dysfunctional tumors are hypersensitive to DNA damaging chemotherapeutic agents like platinum drugs. Although platinum based drugs are currently widely used as conventional chemotherapeutic drugs in breast cancer chemotherapy, their use has several disadvantages. It is therefore of interest to seek out alternative therapeutic metal-based compounds that could overcome the limitations of these platinum based drugs. Ruthenium-based compounds could be the most promising alternative to the platinum drugs. This review highlights the use of BRCA1 as a predictive marker as well as for a potential drug target for anticancer ruthenium compounds.

  12. Determination of cancer risk associated with germ line BRCA1 missense variants by functional analysis.

    PubMed

    Carvalho, Marcelo A; Marsillac, Sylvia M; Karchin, Rachel; Manoukian, Siranoush; Grist, Scott; Swaby, Ramona F; Urmenyi, Turan P; Rondinelli, Edson; Silva, Rosane; Gayol, Luis; Baumbach, Lisa; Sutphen, Rebecca; Pickard-Brzosowicz, Jennifer L; Nathanson, Katherine L; Sali, Andrej; Goldgar, David; Couch, Fergus J; Radice, Paolo; Monteiro, Alvaro N A

    2007-02-15

    Germ line inactivating mutations in BRCA1 confer susceptibility for breast and ovarian cancer. However, the relevance of the many missense changes in the gene for which the effect on protein function is unknown remains unclear. Determination of which variants are causally associated with cancer is important for assessment of individual risk. We used a functional assay that measures the transactivation activity of BRCA1 in combination with analysis of protein modeling based on the structure of BRCA1 BRCT domains. In addition, the information generated was interpreted in light of genetic data. We determined the predicted cancer association of 22 BRCA1 variants and verified that the common polymorphism S1613G has no effect on BRCA1 function, even when combined with other rare variants. We estimated the specificity and sensitivity of the assay, and by meta-analysis of 47 variants, we show that variants with <45% of wild-type activity can be classified as deleterious whereas variants with >50% can be classified as neutral. In conclusion, we did functional and structure-based analyses on a large series of BRCA1 missense variants and defined a tentative threshold activity for the classification missense variants. By interpreting the validated functional data in light of additional clinical and structural evidence, we conclude that it is possible to classify all missense variants in the BRCA1 COOH-terminal region. These results bring functional assays for BRCA1 closer to clinical applicability.

  13. Loss of heterozygosity (LOH) in familial tumors of BRCA1 kindreds

    SciTech Connect

    Neuhausen, S.L.; Marshall, C.J.; Goldgar, D.E.

    1994-09-01

    In this study, we examined two families previously linked to BRCA1. Identification of recombinants in kindreds K2082 and K2035 had narrowed the region to between D17S776 and D17S1184, respectively. Further delineation of the region may be accomplished by examining loss of heterozygosity (LOH) in familial tumors. Five ovarian and six breast tumors from kindred K2082 (including two from sporadic breast cases) and three breast tumors from kindred K2035 were tested for LOH using six BRCA1-linked polymorphic STR markers and one marker at TP53. The two tumors from K2082 which did not share the linked haplotype did not show LOH in the BRCA1 region, nor did one of the tumors from a 17q-linked breast cancer case. Four ovarian and three breast tumors showed complete loss for the BRCA1 region. One ovarian and three breast tumors showed LOH only within the BRCA1 region. In all instances where LOH in the BRCA1 region was observed, the wild type allele was lost. These results therefore confirm the observation of Smith et al. (1992), and provide additional evidence that BRCA1 is a tumor suppressor gene. One of the breast tumors which showed loss within the BRCA1 region allowed us to narrow the region further.

  14. Identification of a founder BRCA1 mutation in the Moroccan population.

    PubMed

    Quiles, F; Teulé, À; Martinussen Tandstad, N; Feliubadaló, L; Tornero, E; Del Valle, J; Menéndez, M; Salinas, M; Wethe Rognlien, V; Velasco, A; Izquierdo, A; Capellá, G; Brunet, J; Lázaro, C

    2016-10-01

    Breast cancer (BC) is the most frequent cancer among women in Morocco. However, the role of the most prevalent BC-predisposing genes, BRCA1 and BRCA2, has been largely unexplored. To help define the role of BRCA1 in BC in Morocco, we characterized the first potential BRCA1 founder mutation in this population. Genetic testing of BRCA1 and BRCA2 in BC high-risk families identified mutation BRCA1 c.5309G>T, p.(Gly1770Val) or G1770V in five independent families from Morocco, suggesting a founder effect. To confirm this hypothesis, haplotype construction was performed using seven intragenic and flanking BRCA1 microsatellite markers. Clinical data were also compiled. Clinical data from carriers of mutation G1770V correspond to data from carriers of BRCA1 pathogenic mutations. Microsatellite analysis showed a common haplotype for the five families in a region comprising 1.54 Mb, confirming G1770V as the first specific founder BRCA1 mutation in the Moroccan population. Our findings contribute to a better understanding of BC genetics in the Moroccan population. Nevertheless, comprehensive studies of mutation G1770V in large series of BC patients from Morocco are needed to assess the real prevalence of this mutation and to improve genetic testing and risk assessment in this population.

  15. BRCA1/2 germline mutations and their clinical importance in Turkish breast cancer patients.

    PubMed

    Cecener, Gulsah; Egeli, Unal; Tunca, Berrin; Erturk, Elif; Ak, Secil; Gokgoz, Sehsuvar; Tasdelen, Ismet; Tezcan, Gulcin; Demirdogen, Elif; Bayram, Nuran; Avci, Nilufer; Evrensel, Turkkan

    2014-10-01

    BRCA1/BRCA2 genes were screened in 117 patients with breast cancer by sequencing. Fourteen percent of patients tested positive for BRCA1/BRCA2 mutations. Four frame shift mutations, four pathogenic missense mutations, and 25 different sequence variations were detected. BRCA mutation positivity was significantly associated with Ki67 (p = .001). BRCA protein expressions were decreased in the patients harboring important mutations and polymorphisms (BRCA1;P508 stop, V1740G, Q1182R, Q1756P and BRCA2;V2466A) related with disease. Our findings contribute significantly to the types of germline BRCA1/BRCA2 mutations and their biological effects in Turkish women. These data could help guide the management of BRCA1/BRCA2 mutation-carrying patients when considering breast-conserving therapy.

  16. Molecular profiles of BRCA1-mutated and matched sporadic breast tumours: relation with clinico-pathological features

    PubMed Central

    Berns, E M J J; Staveren, I L van; Verhoog, L; Ouweland, A M W van de; Gelder, M Meijer-van; Meijers-Heijboer, H; Portengen, H; Foekens, J A; Dorssers, L C J; Klijn, J G M

    2001-01-01

    About 5–10% of breast cancers are hereditary; a genetically and clinically heterogeneous disease in which several susceptibility genes, including BRCA1, have been identified. While distinct tumour features can be used to estimate the likelihood that a breast tumour is caused by a BRCA1 germline mutation it is not yet possible to categorize a BRCA1 mutated tumour. The aim of the present study is to molecularly classify BRCA1 mutated breast cancers by resolving gene expression patterns of BRCA1 and matched sporadic surgical breast tumour specimens. The expression profiles of 6 frozen breast tumour tissues with a proven BRCA1 gene mutation were weighed against those from 12 patients without a known family history but who had similar clinico-pathological characteristics. In addition two fibroblast cultures, the breast cancer cell-line HCC1937 and its corresponding B-lymphoblastoid cell line (heterozygous for mutation BRCA1 5382insC) and an epithelial ovarian cancer cell line (A2780) were studied. Using a high density membrane based array for screening of RNA isolated from these samples and standard algorithms and software, we were able to distinguish subgroups of sporadic cases and a group consisting mainly of BRCA1-mutated breast tumours. Furthermore this pilot analysis revealed a gene cluster that differentially expressed genes related to cell substrate formation, adhesion, migration and cell organization in BRCA1-mutated tumours compared to sporadic breast tumours. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11506493

  17. 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.

  18. A new scoring system for the chances of identifying a BRCA1/2 mutation outperforms existing models including BRCAPRO

    PubMed Central

    Evans, D; Eccles, D; Rahman, N; Young, K; Bulman, M; Amir, E; Shenton, A; Howell, A; Lalloo, F

    2004-01-01

    Methods: DNA samples from affected subjects from 422 non-Jewish families with a history of breast and/or ovarian cancer were screened for BRCA1 mutations and a subset of 318 was screened for BRCA2 by whole gene screening techniques. Using a combination of results from screening and the family history of mutation negative and positive kindreds, a simple scoring system (Manchester scoring system) was devised to predict pathogenic mutations and particularly to discriminate at the 10% likelihood level. A second separate dataset of 192 samples was subsequently used to test the model's predictive value. This was further validated on a third set of 258 samples and compared against existing models. Results: The scoring system includes a cut-off at 10 points for each gene. This equates to >10% probability of a pathogenic mutation in BRCA1 and BRCA2 individually. The Manchester scoring system had the best trade-off between sensitivity and specificity at 10% prediction for the presence of mutations as shown by its highest C-statistic and was far superior to BRCAPRO. Conclusion: The scoring system is useful in identifying mutations particularly in BRCA2. The algorithm may need modifying to include pathological data when calculating whether to screen for BRCA1 mutations. It is considerably less time-consuming for clinicians than using computer models and if implemented routinely in clinical practice will aid in selecting families most suitable for DNA sampling for diagnostic testing. PMID:15173236

  19. RAP80-directed tuning of BRCA1 homologous recombination function at ionizing radiation-induced nuclear foci

    PubMed Central

    Hu, Yiduo; Scully, Ralph; Sobhian, Bijan; Xie, Anyong; Shestakova, Elena; Livingston, David M.

    2011-01-01

    In response to DNA double-strand breaks (DSBs), BRCA1 forms biochemically distinct complexes with certain other DNA damage response proteins. These structures, some of which are required for homologous recombination (HR)-type DSB repair, concentrate at distinct nuclear foci that demarcate sites of genome breakage. Polyubiquitin binding by one of these structures, the RAP80/BRCA1 complex, is required for efficient BRCA1 focal recruitment, but the relationship of this process to the execution of HR has been unclear. We found that this complex actively suppresses otherwise exaggerated, BRCA1-driven HR. By controlling the kinetics by which other BRCA1-interacting proteins that promote HR concentrate together with BRCA1 in nuclear foci, RAP80/BRCA1 complexes suppress excessive DSB end processing, HR-type DSB repair, and overt chromosomal instability. Since chromosomal instability emerges when BRCA1 HR function is either unbridled or absent, active tuning of BRCA1 activity, executed in nuclear foci, is important to genome integrity maintenance. PMID:21406551

  20. Classification of BRCA1 missense variants of unknown clinical significance

    PubMed Central

    Phelan, C; Dapic, V; Tice, B; Favis, R; Kwan, E; Barany, F; Manoukian, S; Radice, P; van der Luijt, R B; van Nesselrooij, B P M; Chenevix-Trench, G; kConFab; Caldes, T; de La Hoya, M; Lindquist, S; Tavtigian, S; Goldgar, D; Borg, A; Narod, S; Monteiro, A

    2005-01-01

    Background: BRCA1 is a tumour suppressor with pleiotropic actions. Germline mutations in BRCA1 are responsible for a large proportion of breast–ovarian cancer families. Several missense variants have been identified throughout the gene but because of lack of information about their impact on the function of BRCA1, predictive testing is not always informative. Classification of missense variants into deleterious/high risk or neutral/low clinical significance is essential to identify individuals at risk. Objective: To investigate a panel of missense variants. Methods and results: The panel was investigated in a comprehensive framework that included (1) a functional assay based on transcription activation; (2) segregation analysis and a method of using incomplete pedigree data to calculate the odds of causality; (3) a method based on interspecific sequence variation. It was shown that the transcriptional activation assay could be used as a test to characterise mutations in the carboxy-terminus region of BRCA1 encompassing residues 1396–1863. Thirteen missense variants (H1402Y, L1407P, H1421Y, S1512I, M1628T, M1628V, T1685I, G1706A, T1720A, A1752P, G1788V, V1809F, and W1837R) were specifically investigated. Conclusions: While individual classification schemes for BRCA1 alleles still present limitations, a combination of several methods provides a more powerful way of identifying variants that are causally linked to a high risk of breast and ovarian cancer. The framework presented here brings these variants nearer to clinical applicability. PMID:15689452

  1. 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

  2. Low expression of bcl-2 in Brca1-associated breast cancers

    PubMed Central

    Freneaux, P; Stoppa-Lyonnet, D; Mouret, E; Kambouchner, M; Nicolas, A; Zafrani, B; Vincent-Salomon, A; Fourquet, A; Magdelenat, H; Sastre-Garau, X

    2000-01-01

    Little data are available concerning the molecular mechanisms of action of Brca1 and Brca2 in breast oncogenesis. Recent experimental results suggest that Brca1 plays a role in the regulation of apoptosis. In order to determine whether the analysis of human tumours would provide data supporting this hypothesis, we have assessed the expression of the antiapoptotic bcl-2 and of the proapoptotic p53 genes in Brca1- and Brca2-associated breast carcinomas. The levels of expression of these genes were compared to those observed in controls and to the mitotic and the apoptotic indexes. Our series were composed of 16 cases of breast carcinoma in women with a germline Brca1 gene mutation, and of four cases with Brca2 mutation. A group of 39 patients aged under 36 years and for whom the search for Brca1 gene mutations was negative, and a group of 36 cases of sporadic cancers without data on their Brca status were used as controls. Immunohistochemistry was used to detect p53 and bcl-2 gene products. Mitotic and apoptotic indexes were higher in Brca1-associated tumours than in controls. No significant difference in p53 immunostaining was observed between the four groups of patients. In contrast, the rate of bcl-2-positive tumours was lower (31%) in Brca1-carcinomas than in carcinomas without Brca1 mutation (90%) (P< 10–3). A strong Bcl-2 expression was found in the four cases of Brca2-associated carcinomas. No significant correlation was observed between p53 and Bcl-2 immunostainings, either in cases or in controls. The association between Brca1 status and Bcl-2 expression remained significant after adjustment for the oestrogen receptor status. Our study shows that a low expression of bcl-2 characterises most Brca1-associated breast carcinomas, a biological trait which seems not to be shared by Brca2-associated tumours nor to be related to oestrogen receptor and/or p53 status.bcl-2 might thus be one of the target genes involved in the oncogenesis related to Brca1 and its

  3. BRCA1 regulates PIG3-mediated apoptosis in a p53-dependent manner.

    PubMed

    Zhang, Wenwen; Luo, Jiayan; Chen, Fengxia; Yang, Fang; Song, Wei; Zhu, Aiyu; Guan, Xiaoxiang

    2015-04-10

    BRCA1 plays a key role in the regulation of p53-dependent target gene transcription activation. Meanwhile, the p53 inducible gene 3 (PIG3) is a downstream target of p53 and is involved in p53-initiated apoptosis. However, little is known about whether BRCA1 can regulate PIG3-mediated apoptosis. Using a tissue microarray containing 149 breast cancer patient samples, we found that BRCA1 and PIG3 expression status were significantly positively correlated (r = 0.678, P < 0.001) and identified a significant positive correlation between high expression of BRCA1 and/or PIG3 and overall survival (OS). Moreover, we reveal that overexpression of BRCA1 significantly increased expression of PIG3 in cells with intact p53, whereas no increase in PIG3 was observed in p53-null MDA-MB-157 cells and p53-depleted HCT116p53-/- cells. Meanwhile, ectopic expression of BRCA1 could not lead to an increase expression level of prohibitin (PHB), which we have previously identified to induce PIG3-mediated apoptosis. Finally, ChIP analysis revealed that PHB can bind to the PIG3 promoter and activate PIG3 transcription independent of p53, although p53 presence did enhance this process. Taken together, our findings suggest that BRCA1 regulates PIG3-mediated apoptosis in a p53-dependent manner, and that PIG3 expression is associated with a better OS in breast cancer patients.

  4. 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

  5. Evaluation of the contribution of the three breast cancer susceptibility genes CHEK2, STK11, and PALB2 in non-BRCA1/2 French Canadian families with high risk of breast cancer.

    PubMed

    Guénard, Frédéric; Pedneault, Christopher St-Laurent; Ouellette, Geneviève; Labrie, Yvan; Simard, Jacques; Durocher, Francine

    2010-08-01

    Inactivating mutations of the CHEK2 and STK11 genes are responsible for Li-Fraumeni and Peutz-Jeghers syndrome, respectively, both autosomal dominant syndromes associated with an increased risk of breast cancer. The PALB2/FANCN gene encodes a nuclear partner of BRCA2 and acts as a linker between BRCA1 and BRCA2. Monoallelic PALB2 truncating mutations were shown to confer higher risk of breast cancer. To evaluate the proportion of French Canadian non-BRCA1/BRCA2 families with high risk of breast cancer potentially harboring alterations in these three breast cancer susceptibility genes, the whole coding and flanking intronic sequences were analyzed in a series of 96 high-risk breast cancer individuals. Despite no PALB2 deleterious truncating mutations being identified, the c.1100delC breast-cancer-associated CHEK2 mutation and a STK11 mutation reported to be the causative mutation in a Peutz-Jeghers family were identified. This extensive analysis also led to the identification of several variants in these genes. Ascertainment of allele frequency of these variants in a cohort of 96 healthy unrelated women suggests a difference in allele frequency for two STK11 intronic variants. In addition, large genomic rearrangements in both STK11 and PALB2 were also examined. Our analysis led to the conclusion that CHEK2, STK11, and PALB2 mutations or large genomic rearrangements of either STK11 or PALB2 are rare, and do not contribute to a substantial fraction of breast cancer susceptibility in high-risk French Canadian breast cancer families.

  6. 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

  7. 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.

  8. 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

  9. 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

  10. 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.

  11. 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

  12. Concerted Transcriptional Regulation by BRCA1 and COBRA1 in Breast Cancer Cells

    PubMed Central

    Aiyar, Sarah E.; Cho, HyungJun; Lee, Jae; Li, Rong

    2007-01-01

    Cofactor of BRCA1 (COBRA1) was first identified as a protein that binds to the breast cancer susceptibility gene product BRCA1. COBRA1 modulates estrogen-dependent and independent transcription and suppresses the growth of breast cancer cells. Its expression is significantly reduced in metastatic and recurrent breast cancer, pointing to a tumor suppressor function in breast cancer development. In light of these initial implications of COBRA1 in human breast cancer, the current investigation sought to obtain more direct functional evidence that links COBRA1 with BRCA1 in transcriptional regulation in breast cancer cells. Small hairpin RNA (shRNA)-mediated gene knockdown and gene expression microarray were used to study the impact of COBRA1 and BRCA1 on global transcription in the same breast cancer cell background. The gene expression profiling study in tissue culture cells uncovers a significant overlap of COBRA1- and BRCA1-regulated genes, many of which have been previously implicated in breast cancer progression. The data shown herein support the notion that COBRA1 and BRCA1 may engage in common gene regulatory pathways to suppress breast cancer progression. PMID:18071589

  13. Identification of a non-canonical nuclear localization signal (NLS) in BRCA1 that could mediate nuclear localization of splice variants lacking the classical NLS.

    PubMed

    Korlimarla, Aruna; Bhandary, Lekhana; Prabhu, Jyothi S; Shankar, Hema; Sankaranarayanan, Hari; Kumar, Pravin; Remacle, Jose; Natarajan, Dipa; Sridhar, T S

    2013-06-01

    The breast cancer type 1 susceptibility gene (BRCA1) is a tumor suppressor gene, mutations or loss of which lead to genomic instability and breast cancer. BRCA1 protein is part of a large multi-protein complex involved in a variety of DNA repair and transcription regulatory functions. At least four splice variants have been described and these differ in their function and tissue and spatio-temporal expression patterns. Structural analysis has revealed the presence of two nuclear localization signals (NLS) located in exon 11 of BRCA1. Interestingly, a splice variant of the protein that lacks both of the known NLS still manages to gain entry to the nucleus. While there is experimental proof for the translocation of these proteins by binding to other established nuclear proteins, we examined the possibility of a hitherto unidentified NLS in this particular variant. In this paper, we present evidence for the existence of a previously unreported non-canonical NLS contained within the first 39 amino acids of exon 11. A fusion protein with this 39mer and a reporter green fluorescent protein translocated into the nucleus when it was expressed in breast epithelial cells. We demonstrate the presence of a hitherto unreported noncanonical NLS in exon 11a of BRCA1. This NLS might aid proteins that were encoded by splice variants and lack the canonical NLS to localize to the nucleus. PMID:23666596

  14. BRCA1/BRCA2 founder mutations and cancer risks: impact in the western Danish population.

    PubMed

    Nielsen, Henriette Roed; Nilbert, Mef; Petersen, Janne; Ladelund, Steen; Thomassen, Mads; Pedersen, Inge Søkilde; Hansen, Thomas V O; Skytte, Anne-Bine; Borg, Åke; Therkildsen, Christina

    2016-10-01

    Mutations in the BRCA1 and BRCA2 genes significantly contribute to hereditary breast cancer and ovarian cancer, but the phenotypic effect from different mutations is insufficiently recognized. We used a western Danish clinic-based cohort of 299 BRCA families to study the female cancer risk in mutation carriers and their untested first-degree relatives. Founder mutations were characterized and the risk of cancer was assessed in relation to the specific mutations. In BRCA1, the cumulative cancer risk at age 70 was 35 % for breast cancer and 29 % for ovarian cancer. In BRCA2, the cumulative risk was 44 % for breast cancer and 15 % for ovarian cancer. We identified 47 distinct BRCA1 mutations and 48 distinct mutations in BRCA2. Among these, 8 founder mutations [BRCA1 c.81-?_4986+?del, c.3319G>T (p.Glu1107*), c.3874delT and c.5213G>A (p.Gly1738Glu) and BRCA2 c.6373delA, c.7008-1G>A, c.7617+1G>A and c.8474delC] were found to account for 23 % of the BRCA1 mutations and for 32 % of the BRCA2 mutations. The BRCA1 mutation c.3319G>T was, compared to other BRCA1 mutations, associated with a higher risk for ovarian cancer. In conclusion, founder mutations in BRCA1 and BRCA2 contribute to up to one-third of the families in western Denmark and among these the BRCA1 c.3319G>T mutation is potentially linked to an increased risk of ovarian cancer.

  15. 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.

  16. Rapid detection of regionally clustered germ-line BRCA1 mutations by multiplex heteroduplex analysis

    SciTech Connect

    Gayther, S.A.; Harrington, P.; Russell, P.

    1996-03-01

    Germ-line mutations of the BRCA1 gene are responsible for a substantial proportion of families with multiple cases of early-onset breast and/or ovarian cancer. Since the isolation of BRCA1 last year, >65 distinct mutations scattered throughout the coding region have been detected, making analysis of the gene time consuming and technically challenging. We have developed a multiplex heteroduplex analysis that is designed to analyze one-quarter of the coding sequence in a single-step screening procedure and that will detect {approximately}50% of all BRCA1 mutations so far reported in breast/ovarian cancer families. We have used this technique to analyze BRCA1 in 162 families with a history of breast and/or ovarian cancer and identified 12 distinct mutations in 35 families. 20 refs., 2 figs., 2 tabs.

  17. 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

  18. 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

  19. 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

  20. A BRCA1-interacting lncRNA regulates homologous recombination.

    PubMed

    Sharma, Vivek; Khurana, Simran; Kubben, Nard; Abdelmohsen, Kotb; Oberdoerffer, Philipp; Gorospe, Myriam; Misteli, Tom

    2015-11-01

    Long non-coding RNAs (lncRNAs) are important players in diverse biological processes. Upon DNA damage, cells activate a complex signaling cascade referred to as the DNA damage response (DDR). Using a microarray screen, we identify here a novel lncRNA, DDSR1 (DNA damage-sensitive RNA1), which is induced upon DNA damage. DDSR1 induction is triggered in an ATM-NF-κB pathway-dependent manner by several DNA double-strand break (DSB) agents. Loss of DDSR1 impairs cell proliferation and DDR signaling and reduces DNA repair capacity by homologous recombination (HR). The HR defect in the absence of DDSR1 is marked by aberrant accumulation of BRCA1 and RAP80 at DSB sites. In line with a role in regulating HR, DDSR1 interacts with BRCA1 and hnRNPUL1, an RNA-binding protein involved in DNA end resection. Our results suggest a role for the lncRNA DDSR1 in modulating DNA repair by HR.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. Two PALB2 germline mutations found in both BRCA1+ and BRCAx familial breast cancer.

    PubMed

    Downs, Bradley; Kim, Yeong C; Xiao, Fengxia; Snyder, Carrie; Chen, Peixian; Fleissner, Elizabeth A; Becirovic, Dina; Wen, Hongxiu; Sherman, Simon; Cowan, Kenneth H; Lynch, Henry T; Wang, San Ming

    2015-05-01

    Partner and localizer of BRCA2 (PALB2), plays an important functional role in DNA damage repair. Recent studies indicate that germline mutations in PALB2 predispose individuals to a high risk of developing familial breast cancer. Therefore, comprehensive identification of PALB2 germline mutations is potentially important for understanding their roles in tumorigenesis and for testing their potential utility as clinical targets. Most of the previous studies of PALB2 have focused on familial breast cancer cases with normal/wild-type BRCA1 and BRCA2 (BRCAx). We hypothesize that PALB2 genetic mutations also exist in individuals with BRCA mutations (BRCA+). To test this hypothesis, PALB2 germline mutations were screened in 107 exome data sets collected from familial breast cancer families who were either BRCA1+ or BRCAx. Two novel heterozygous mutations predicted to alter the function of PALB2 were identified (c.2014G>C, p.E672Q and c.2993G>A, p.G998E). Notably, both of these mutations co-existed in BRCA1+ and BRCA1x families. These studies show that mutations in PALB2 can occur independent of the status of BRCA1 mutations, and they highlight the importance to include BRCA1+ families in PALB2 mutation screens. PMID:25833210

  7. 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.

  8. 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

  9. 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

  10. 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

  11. 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.

  12. Breed-related differences in altered BRCA1 expression, phenotype and subtype in malignant canine mammary tumors.

    PubMed

    Im, Keum-Soon; Kim, Il-Hwan; Kim, Na-Hyun; Lim, Ha-Young; Kim, Jong-Hyuk; Sur, Jung-Hyang

    2013-03-01

    BRCA1 is a high-penetrance breast cancer susceptibility gene and BRCA1-associated breast cancer has a high familial prevalence that is more common among certain populations of humans. A similar high prevalence also exists for canine mammary tumors (CMTs) and the objective of this study was to determine the breed-related differences in malignant CMTs. Comparative analyses of the expression of various prognostic factors for CMTs, including BRCA1, estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2) were conducted on 139 malignant CMT cases from five breeds with the highest prevalence of CMTs in Korea. Significant breed-related differences were observed in the expression of BRCA1 (P=0.003), histological grade (P=0.038), and extensive lymphatic invasion (P=0.042). The Shih Tzu breed had the highest proportion of dogs with malignant CMT and strong overexpression of BRCA1. Cytoplasmic and membranous expression of BRCA1 was associated with the ER negative (P=0.004), PR negative (P=0.046), and triple negative (ER, PR, and HER-2 negative; P=0.016) phenotype and the basal-like molecular subtype (P=0.019) in Shih Tzu dogs. Since these features are similar to BRCA1-related human breast cancer, dogs with BRCA1-associated CMT, particularly Shih Tzu dogs, may serve as a suitable spontaneous model, although additional molecular studies are needed. PMID:22901454

  13. Double PALB2 and BRCA1/BRCA2 mutation carriers are rare in breast cancer and breast-ovarian cancer syndrome families from the French Canadian founder population

    PubMed Central

    ANCOT, FRÉDÉRIC; ARCAND, SUZANNA L.; MES-MASSON, ANNE-MARIE; PROVENCHER, DIANE M.; TONIN, PATRICIA N.

    2015-01-01

    French Canadian families with breast cancer and breast-ovarian cancer syndrome harbor specific BRCA1, BRCA2 and PALB2 germline mutations, which have been attributed to common founders. Mutations in these genes confer an increased risk to breast and ovarian cancers, and have been identified to play a role in and directly interact with the common homologous recombination DNA repair pathways. Our previous study described the case of a female diagnosed with breast cancer at 45 years old, who harbored the PALB2:c.2323C>T [p.Q775X] and BRCA2:c.9004G>A [p.E3002K] germline mutations, which have been found to recur in the French Canadian cancer families. As the frequency of double heterozygous carriers of breast-ovarian cancer susceptibility alleles is unknown, and due to the possibility that there may be implications for genetic counseling and management for these carriers, the present study investigated the co-occurrence of BRCA1/BRCA2 and PALB2 mutations in the French Canadian cancer families. The PALB2:c.2323C>T [p.Q775X] mutation, which is the only PALB2 mutation to have been identified in French Canadian cancer families, was screened in 214 breast cancer cases and 22 breast-ovarian cancer cases from 114 BRCA1/BRCA2 mutation-positive French Canadian breast cancer (n=61) and breast-ovarian cancer (n=53) families using a tailored polymerase chain reaction-based TaqMan® SNP Genotyping Assay. No additional PALB2:c.2323C>T [p.Q775X] mutation carriers were identified among the BRCA1/BRCA2 mutation carriers. The results suggest that carriers of the PALB2:c.2323C>T [p.Q775X] mutation rarely co-occur in French Canadian breast cancer and breast-ovarian cancer families harboring BRCA1 or BRCA2 mutations. PMID:26137147

  14. 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

  15. Breast Cancer Risk Assessment: Moving Beyond BRCA 1 and 2.

    PubMed

    Scalia-Wilbur, Jennifer; Colins, Bradley L; Penson, Richard T; Dizon, Don S

    2016-01-01

    The National Cancer Institute estimates that 12.3% of all women (about 1 in 8) would be diagnosed with breast cancer throughout their lifetime. In 2015, a projected 231,840 new cases are expected in the United States, accompanied by 40,290 deaths. Presently, breast cancer is responsible for 6.8% of all cancer deaths, and roughly 30% of all cancers in women. Since the discovery of the BRCA gene in 1994, efforts have been made to develop effective screening methods for breast cancer detection. Although the BRCA gene certainly opened the door to breast cancer genetics, a wide variety of new genes have recently been linked to breast cancer risk, and the tools to screen for genes beyond just BRCA1 and BRCA2 are available. However, the indications for both screening and prevention of inherited predispositions beyond BRCA1 and BRCA2 are not entirely clear, and as a result, much of the ongoing work is aimed at determining the role of broader genetic screening in women deemed at sufficiently high risk for breast cancer based on family history. On this topic, we provide a brief overview of the genes associated with breast cancer risk as well as the technological platforms available to patients. We conclude by discussing recommendations of expert groups and what they practically mean for patients.

  16. Genetic mapping of the BRCA1 region on chromosome 17q21

    SciTech Connect

    Albertson, H.; Plaetke, R.; Ballard, L.; Fujimoto, E.; Connolly, J.; Lawrence, E.; Rodriquez, P.; Robertson, M.; Bradley, P.; Milner, B. )

    1994-03-01

    Chromosome 17q21 harbors a gene (BRCA1) associated with a hereditary form of breast cancer. As a step toward identification of this gene itself the authors 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 they 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. 31 refs., 3 figs., 21 tabs.

  17. The status of poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors in ovarian cancer, part 2: extending the scope beyond olaparib and BRCA1/2 mutations.

    PubMed

    Miller, Rowan E; Ledermann, Jonathan A

    2016-09-01

    Poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors have shown clinical activity in epithelial ovarian cancer, leading both the US Food and Drug Administration (FDA) and the European Medicines Agency to approve olaparib for tumors characterized by BRCA1 and BRCA2 mutations. However, it is becoming increasingly evident that tumors that share molecular features with BRCA-mutant tumors-a concept known as BRCAness-also may exhibit defective homologous recombination DNA repair, and therefore will respond to PARP inhibition. A number of strategies have been proposed to identify BRCAness, including identifying defects in other genes that modulate homologous recombination and characterizing the mutational and transcriptional signatures of BRCAness. In addition to olaparib, a number of other PARP inhibitors are in clinical development. This article reviews the development of PARP inhibitors other than olaparib, and discusses the evidence for PARP inhibitors beyond BRCA1/2-mutant ovarian cancer. PMID:27673289

  18. Selective resistance to the PARP inhibitor olaparib in a mouse model for BRCA1-deficient metaplastic breast cancer

    PubMed Central

    Henneman, Linda; van Miltenburg, Martine H.; Michalak, Ewa M.; Braumuller, Tanya M.; Jaspers, Janneke E.; Drenth, Anne Paulien; de Korte-Grimmerink, Renske; Gogola, Ewa; Szuhai, Karoly; Schlicker, Andreas; Bin Ali, Rahmen; Pritchard, Colin; Huijbers, Ivo J.; Berns, Anton; Rottenberg, Sven; Jonkers, Jos

    2015-01-01

    Metaplastic breast carcinoma (MBC) is a rare histological breast cancer subtype characterized by mesenchymal elements and poor clinical outcome. A large fraction of MBCs harbor defects in breast cancer 1 (BRCA1). As BRCA1 deficiency sensitizes tumors to DNA cross-linking agents and poly(ADP-ribose) polymerase (PARP) inhibitors, we sought to investigate the response of BRCA1-deficient MBCs to the PARP inhibitor olaparib. To this end, we established a genetically engineered mouse model (GEMM) for BRCA1-deficient MBC by introducing the MET proto-oncogene into a BRCA1-associated breast cancer model, using our novel female GEMM ES cell (ESC) pipeline. In contrast to carcinomas, BRCA1-deficient mouse carcinosarcomas resembling MBC show intrinsic resistance to olaparib caused by increased P-glycoprotein (Pgp) drug efflux transporter expression. Indeed, resistance could be circumvented by using another PARP inhibitor, AZD2461, which is a poor Pgp substrate. These preclinical findings suggest that patients with BRCA1-associated MBC may show poor response to olaparib and illustrate the value of GEMM-ESC models of human cancer for evaluation of novel therapeutics. PMID:26100884

  19. Selective resistance to the PARP inhibitor olaparib in a mouse model for BRCA1-deficient metaplastic breast cancer.

    PubMed

    Henneman, Linda; van Miltenburg, Martine H; Michalak, Ewa M; Braumuller, Tanya M; Jaspers, Janneke E; Drenth, Anne Paulien; de Korte-Grimmerink, Renske; Gogola, Ewa; Szuhai, Karoly; Schlicker, Andreas; Bin Ali, Rahmen; Pritchard, Colin; Huijbers, Ivo J; Berns, Anton; Rottenberg, Sven; Jonkers, Jos

    2015-07-01

    Metaplastic breast carcinoma (MBC) is a rare histological breast cancer subtype characterized by mesenchymal elements and poor clinical outcome. A large fraction of MBCs harbor defects in breast cancer 1 (BRCA1). As BRCA1 deficiency sensitizes tumors to DNA cross-linking agents and poly(ADP-ribose) polymerase (PARP) inhibitors, we sought to investigate the response of BRCA1-deficient MBCs to the PARP inhibitor olaparib. To this end, we established a genetically engineered mouse model (GEMM) for BRCA1-deficient MBC by introducing the MET proto-oncogene into a BRCA1-associated breast cancer model, using our novel female GEMM ES cell (ESC) pipeline. In contrast to carcinomas, BRCA1-deficient mouse carcinosarcomas resembling MBC show intrinsic resistance to olaparib caused by increased P-glycoprotein (Pgp) drug efflux transporter expression. Indeed, resistance could be circumvented by using another PARP inhibitor, AZD2461, which is a poor Pgp substrate. These preclinical findings suggest that patients with BRCA1-associated MBC may show poor response to olaparib and illustrate the value of GEMM-ESC models of human cancer for evaluation of novel therapeutics.

  20. 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

  1. 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.

  2. 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

  3. Prevalence of BRCA1 and BRCA2 mutations in breast cancer patients from Cuba.

    PubMed

    Rodriguez, Rolando Comacho; Esperon, Antonio Alejandro; Ropero, Ramon; Rubio, Maria Caridad; Rodriguez, Ronald; Ortiz, Rosa M; Anta, Juan J Lence; de los Rios, Mario; Carnesolta, Deyanira; del Olivera, Maria C; Vansam, Somalia Stiu; Royer, Robert; Akbari, Mohammad R; Donenberg, Talia; Narod, Steven A

    2008-01-01

    The contribution of BRCA1 and BRCA2 to breast cancer incidence in Cuba has not yet been explored. In order to estimate the proportion of breast cancers due to BRCA1 and BRCA2 mutations in Cuba, and to identify possible Cuban founder mutations, we conducted a study of unselected breast cancer patients from Havana, Cuba. We enrolled 336 women with breast cancer from a large public hospital in the city. A family history of cancer was obtained from each patient and a blood sample was processed for DNA analysis. Mutations in BRCA1 and BRCA2 were sought using a combination of techniques, but all mutations were confirmed by direct sequencing. We were able to successfully complete testing on samples from 307 women. Among these, eight mutations were identified (seven in BRCA2 and one in BRCA1) representing 2.6% of the total, including 10% of familial cases and 10% of cases under age forty. One BRCA2 mutation (c.3394C > T) was found in two women, but no clear example of a founder mutation was identified. In summary, BRCA1 and BRCA2 mutations are not uncommon in Cuban women with breast cancer, but the absence of founder mutations precludes the development of a rapid and inexpensive clinical screening test.

  4. Prevalence of BRCA1 and BRCA2 mutations in unselected breast cancer patients from Peru.

    PubMed

    Abugattas, J; Llacuachaqui, M; Allende, Y Sullcahuaman; Velásquez, A Arias; Velarde, R; Cotrina, J; Garcés, M; León, M; Calderón, G; de la Cruz, M; Mora, P; Royer, R; Herzog, J; Weitzel, J N; Narod, S A

    2015-10-01

    The prevalence of BRCA1 and BRCA2 mutations among breast cancer patients in Peru has not yet been explored. We enrolled 266 women with breast cancer from a National cancer hospital in Lima, Peru, unselected for age or family history. DNA was screened with a panel of 114 recurrent Hispanic BRCA mutations (HISPANEL). Among the 266 cases, 13 deleterious mutations were identified (11 in BRCA1 and 2 in BRCA2), representing 5% of the total. The average age of breast cancer in the mutation-positive cases was 44 years. BRCA1 185delAG represented 7 of 11 mutations in BRCA1. Other mutations detected in BRCA1 included: two 2080delA, one 943ins10, and one 3878delTA. The BRCA2 3036del4 mutation was seen in two patients. Given the relatively low cost of the HISPANEL test, one should consider offering this test to all Peruvian women with breast or ovarian cancer.

  5. 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

  6. Prevalence of BRCA1 and BRCA2 mutations in unselected breast cancer patients from Peru

    PubMed Central

    Abugattas, Julio; Llacuachaqui, Marcia; Allende, Yasser Sullcahuaman; Velásquez, Abelardo Arias; Velarde, Raúl; Cotrina, José; Garcés, Milko; León, Mauricio; Calderón, Gabriela; de la Cruz, Miguel; Mora, Pamela; Royer, Robert; Herzog, Josef; Weitzel, Jeffrey N; Narod, Steven A

    2014-01-01

    The prevalence of BRCA1 and BRCA2 mutations among breast cancer patients in Peru has not yet been explored. We enrolled 266 women with breast cancer from a National cancer hospital in Lima, Peru, unselected for age or family history. DNA was screened with a panel of 114 recurrent Hispanic BRCA mutations (HISPANEL). Among the 266 cases, thirteen deleterious mutations were identified (eleven in BRCA1 and two in BRCA2), representing 5% of the total. The average age of breast cancer in the mutation-positive cases was 44 years. BRCA1 185delAG represented seven of the eleven mutations in BRCA1. Other mutations detected in BRCA1 included: two 2080delA, one 943ins10, and one 3878delTA. The BRCA2 3036del4 mutation was seen in two patients. Given the relatively low cost of the HISPANEL test, one should consider offering this test to all Peruvian women with breast or ovarian cancer. PMID:25256238

  7. Robust BRCA1-like classification of copy number profiles of samples repeated across different datasets and platforms.

    PubMed

    Schouten, Philip C; Grigoriadis, Anita; Kuilman, Thomas; Mirza, Hasan; Watkins, Johnathan A; Cooke, Saskia A; van Dyk, Ewald; Severson, Tesa M; Rueda, Oscar M; Hoogstraat, Marlous; Verhagen, Caroline V M; Natrajan, Rachael; Chin, Suet-Feung; Lips, Esther H; Kruizinga, Janneke; Velds, Arno; Nieuwland, Marja; Kerkhoven, Ron M; Krijgsman, Oscar; Vens, Conchita; Peeper, Daniel; Nederlof, Petra M; Caldas, Carlos; Tutt, Andrew N; Wessels, Lodewyk F; Linn, Sabine C

    2015-08-01

    Breast cancers with BRCA1 germline mutation have a characteristic DNA copy number (CN) pattern. We developed a test that assigns CN profiles to be 'BRCA1-like' or 'non-BRCA1-like', which refers to resembling a BRCA1-mutated tumor or resembling a tumor without a BRCA1 mutation, respectively. Approximately one third of the BRCA1-like breast cancers have a BRCA1 mutation, one third has hypermethylation of the BRCA1 promoter and one third has an unknown reason for being BRCA1-like. This classification is indicative of patients' response to high dose alkylating and platinum containing chemotherapy regimens, which targets the inability of BRCA1 deficient cells to repair DNA double strand breaks. We investigated whether this classification can be reliably obtained with next generation sequencing and copy number platforms other than the bacterial artificial chromosome (BAC) array Comparative Genomic Hybridization (aCGH) on which it was originally developed. We investigated samples from 230 breast cancer patients for which a CN profile had been generated on two to five platforms, comprising low coverage CN sequencing, CN extraction from targeted sequencing panels (CopywriteR), Affymetrix SNP6.0, 135K/720K oligonucleotide aCGH, Affymetrix Oncoscan FFPE (MIP) technology, 3K BAC and 32K BAC aCGH. Pairwise comparison of genomic position-mapped profiles from the original aCGH platform and other platforms revealed concordance. For most cases, biological differences between samples exceeded the differences between platforms within one sample. We observed the same classification across different platforms in over 80% of the patients and kappa values of at least 0.36. Differential classification could be attributed to CN profiles that were not strongly associated to one class. In conclusion, we have shown that the genomic regions that define our BRCA1-like classifier are robustly measured by different CN profiling technologies, providing the possibility to retro- and prospectively

  8. 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.

  9. 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

  10. 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

  11. Direct selection of expressed sequences within a 1-Mb region flanking BRCA1 on human chromosome 17q21

    SciTech Connect

    Osborne-Lawrence, S.; Welcsh, P.L.; Spillman, M.

    1995-01-01

    Direct selection of genes within the interval of chromosome 17q21 containing BRCA1 was performed. YAC and cosmid contigs spanning the BRCA1 region were used to select cDNA clones from pools of cDNAs derived from human placenta, HeLa cells, activated T cells, and fetal head. A minimum set of 48 fragments of nonoverlapping cDNAs that unequivocally mapped within a 1-Mb region was identified, although it is not yet known how many of these are derived from the same transcript. DNA sequence analyses revealed that 4 of these cDNAs were derived from known genes (EDH17B2, glucose-6-phosphatase, IAI.3B, and E1AF), 1 is a member of a previously described gene family (EMG-17), and 7 share substantial identity with previously described genes from human or other species. The remainder showed no significant homology to known genes. Limited PCR-based expression profiles of a set of 13 of the genes were performed, and all gave positive results with at least some cDNA sources supporting the contention that they truly represent transcribed sequences. A comparison between genes obtained from this region by direct selection with those obtained by direct screening or exon trapping revealed that over 90% of the genes identified by exon trapping were represented in the selected material and that at least two additional genes that appear to represent low abundance transcripts with restricted expression profiles were identified by selection but not by other means. 39 refs., 3 figs., 2 tabs.

  12. 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…

  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. 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

  15. 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.

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

    PubMed Central

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

    2014-01-01

    Replication fork stalling can promote genomic instability, predisposing to cancer and other diseases1–3. Stalled replication forks may be processed by sister chromatid recombination (SCR), generating error-free or error-prone homologous recombination (HR) outcomes4–8. 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 forks9. Although BRCA1 and BRCA2 affect replication fork processing10–12, direct evidence that BRCA genes regulate HR at stalled chromosomal replication forks is lacking due to a dearth of tools for studying this process. We report that the Escherichia coli Tus/Ter complex13–16 can be engineered to induce site-specific replication fork stalling and chromosomal HR/SCR in mammalian cells. Tus/Ter-induced HR entails processing of bidirectionally arrested forks. We find that the BRCA1 C-terminal tandem BRCT repeat and regions of BRCA1 encoded by exon 11—two BRCA1 elements implicated in tumor suppression—control Tus/Ter-induced HR. 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 restriction endonuclease-mediated chromosomal double strand break (DSB). Therefore, HR at stalled forks is regulated differently from HR at DSBs arising independently of a fork. We propose that aberrant long-tract HR at stalled replication forks contributes to genomic instability and breast/ovarian cancer predisposition in BRCA mutant cells. PMID:24776801

  17. 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

  18. Brief Assessment of Parents’ Attitudes Toward Testing Minor Children for Hereditary Breast/Ovarian Cancer Genes: Development and Validation of the Pediatric BRCA1/2 Testing Attitudes Scale (P-TAS)

    PubMed Central

    Peshkin, Beth N.; DeMarco, Tiffani A.; Garber, Judy E.; Valdimarsdottir, Heiddis B.; Patenaude, Andrea F.; Schneider, Katherine A.; Schwartz, Marc D.

    2009-01-01

    Objective Predictive genetic testing for hereditary breast/ovarian cancer risk (BRCA1/2 testing) is not recommended for minor children due to its lack of immediate medical benefit and potential psychological risk. Yet, tested mothers are often interested in learning about their children's cancer risks via pediatric BRCA1/2 testing, raising a host of bioethical concerns. However, no reliable or valid tool exists to formally gauge parents’ interest in such testing. The aim of this study was to develop and evaluate a new measure for use in genetic research and consultation, known as the Pediatric BRCA1/2 Testing Attitudes Scale (P-TAS). Methods After pretest genetic counseling and provision of a blood sample for BRCA1/2 testing, the P-TAS was administered to 187 mothers of children between 8- and 21-years-old. The measure was also given to 96 of the mothers’ nontested co-parents. Analyses of the factor structure and psychometric properties of the measure were performed in mothers and confirmed in their co-parents. Results The two factors of the P-TAS, labeled Attitudes and Beliefs (Factor 1) and Decision Making and Communication (Factor 2), accounted for 62.9% of the variance and were reliable (Cronbach's coefficient αs =.70 and.90, respectively); the structure and properties were largely confirmed among co-parents. Validity was indicated through its convergence with related constructs. Conclusions This new tool may be integrated into genetic counseling research to better assess parents’ attitudes and interests in pediatric BRCA1/2 testing. Such information may help guide ongoing discussions about the appropriateness of testing in adolescent or young adult children. PMID:18385162

  19. Consanguinity Protecting Effect Against Breast Cancer among Tunisian Women: Analysis of BRCA1 Haplotypes.

    PubMed

    Medimegh, Imen; Troudi, Wafa; Omrane, Ines; Ayari, Hajer; Uhrhummer, Nancy; Majoul, Hamdi; Benayed, Farhat; Mezlini, Amel; Bignon, Yves-Jean; Sibille, Catherine; Elgaaied, Amel Benammar

    2015-01-01

    The purpose of this study is to assess the effect of consanguinity on breast cancer incidence in Tunisia. We conducted a case-control study to evaluate the involvement of heterozygote and homozygote haplotypes of BRCA1 gene SNPs according to consanguinity among 40 cases of familial breast cancer, 46 cases with sporadic breast cancer and 34 healthy controls. We showed significant difference in consanguinity rate between breast cancer patients versus healthy controls P = 0.001. Distribution of homozygous BRCA1 haplotypes among healthy women versus breast cancer patients was significantly different; p=0.02. Parental consanguinity seems to protect against breast cancer in the Tunisian population. PMID:25987085

  20. 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

  1. 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.

  2. Primary Peritoneal Carcinoma in a BRCA1/2-negative, PALB2-positive patient.

    PubMed

    Kahn, Ryan; Garcia-Soto, Arlene; Silva-Smith, Rachel; Pinto, Andre; George, Sophia H L

    2016-08-01

    •First reported case of PPC after BSO in a BRCA1/2-negative, PALB2-positive patient•The PALB2 mutation and genetic counseling is discussed•Multi-gene panel testing can benefit prognostic factors and targeted therapy. PMID:27547810

  3. Breast cancer risk factors differ between Asian and white women with BRCA1/2 mutations.

    PubMed

    de Bruin, Monique A; Kwong, Ava; Goldstein, Benjamin A; Lipson, Jafi A; Ikeda, Debra M; McPherson, Lisa; Sharma, Bhavna; Kardashian, Ani; Schackmann, Elizabeth; Kingham, Kerry E; Mills, Meredith A; West, Dee W; Ford, James M; Kurian, Allison W

    2012-09-01

    The prevalence and penetrance of BRCA1 and BRCA2 (BRCA1/2) mutations may differ between Asians and whites. We investigated BRCA1/2 mutations and cancer risk factors in a clinic-based sample. BRCA1/2 mutation carriers were enrolled from cancer genetics clinics in Hong Kong and California according to standardized entry criteria. We compared BRCA mutation position, cancer history, hormonal and reproductive exposures. We analyzed DNA samples for single-nucleotide polymorphisms reported to modify breast cancer risk. We performed logistic regression to identify independent predictors of breast cancer. Fifty Asian women and forty-nine white American women were enrolled. BRCA1 mutations were more common among whites (67 vs. 42 %, p = 0.02), and BRCA2 mutations among Asians (58 vs. 37 %, p = 0.04). More Asians had breast cancer (76 vs. 53 %, p = 0.03); more whites had relatives with breast cancer (86 vs. 50 %, p = 0.0003). More whites than Asians had breastfed (71 vs. 42 %, p = 0.005), had high BMI (median 24.3 vs. 21.2, p = 0.04), consumed alcohol (2 drinks/week vs. 0, p < 0.001), and had oophorectomy (61 vs. 34 %, p = 0.01). Asians had a higher frequency of risk-associated alleles in MAP3K1 (88 vs. 59 %, p = 0.005) and TOX3/TNRC9 (88 vs. 55 %, p = 0.0002). On logistic regression, MAP3K1 was associated with increased breast cancer risk for BRCA2, but not BRCA1 mutation carriers; breast density was associated with increased risk among Asians but not whites. We found significant differences in breast cancer risk factors between Asian and white BRCA1/2 mutation carriers. Further investigation of racial differences in BRCA1/2 mutation epidemiology could inform targeted cancer risk-reduction strategies.

  4. Male Fertility Defect Associated with Disrupted BRCA1-PALB2 Interaction in Mice*

    PubMed Central

    Simhadri, Srilatha; Peterson, Shaun; Patel, Dharm S.; Huo, Yanying; Cai, Hong; Bowman-Colin, Christian; Miller, Shoreh; Ludwig, Thomas; Ganesan, Shridar; Bhaumik, Mantu; Bunting, Samuel F.; Jasin, Maria; Xia, Bing

    2014-01-01

    PALB2 links BRCA1 and BRCA2 in homologous recombinational repair of DNA double strand breaks (DSBs). Mono-allelic mutations in PALB2 increase the risk of breast, pancreatic, and other cancers, and biallelic mutations cause Fanconi anemia (FA). Like Brca1 and Brca2, systemic knock-out of Palb2 in mice results in embryonic lethality. In this study, we generated a hypomorphic Palb2 allele expressing a mutant PALB2 protein unable to bind BRCA1. Consistent with an FA-like phenotype, cells from the mutant mice showed hypersensitivity and chromosomal breakage when treated with mitomycin C, a DNA interstrand crosslinker. Moreover, mutant males showed reduced fertility due to impaired meiosis and increased apoptosis in germ cells. Interestingly, mutant meiocytes showed a significant defect in sex chromosome synapsis, which likely contributed to the germ cell loss and fertility defect. Our results underscore the in vivo importance of the PALB2-BRCA1 complex formation in DSB repair and male meiosis. PMID:25016020

  5. 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

  6. 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

  7. 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

  8. Mutational analysis of BRCA1/2 in a group of 134 consecutive ovarian cancer patients. Novel and recurrent BRCA1/2 alterations detected by next generation sequencing.

    PubMed

    Ratajska, Magdalena; Krygier, Magdalena; Stukan, Maciej; Kuźniacka, Alina; Koczkowska, Magdalena; Dudziak, Mirosław; Śniadecki, Marcin; Dębniak, Jarosław; Wydra, Dariusz; Brozek, Izabela; Biernat, Wojciech; Borg, Ake; Limon, Janusz; Wasąg, Bartosz

    2015-05-01

    The importance of proper mutational analysis of BRCA1/2 in individuals at risk for hereditary breast and ovarian cancer syndrome is widely accepted. Standard genetic screening includes targeted analysis of recurrent, population-specific mutations. The purpose of the study was to establish the frequency of germline BRCA1/2 mutations in a group of 134 unrelated patients with primary ovarian cancer. Next generation sequencing analysis revealed a presence of 20 (14.9%) mutations, where 65% (n = 13) were recurrent BRCA1 alterations included in the standard diagnostic panel in northern Poland. However, the remaining seven BRCA1/2 mutations (35%) would be missed by the standard approach and were detected in unique patients. A substantial proportion (n = 5/12; 41%) of mutation-positive individuals with complete family history reported no incidence of breast or ovarian cancer in their relatives. This observation, together with the raising perspectives for personalized therapy targeting BRCA1/2 signaling pathways indicates the necessity of comprehensive genetic screening in all ovarian cancer patients. However, due to the limited sensitivity of the standard genetic screening presented in this study (65%) an application of next generation sequencing in molecular diagnostics of BRCA1/2 genes should be considered.

  9. Predictive Value of BRCA1, ERCC1, ATP7B, PKM2, TOPOI, TOPΟ-IIA, TOPOIIB and C-MYC Genes in Patients with Small Cell Lung Cancer (SCLC) Who Received First Line Therapy with Cisplatin and Etoposide

    PubMed Central

    Karachaliou, Niki; Papadaki, Chara; Lagoudaki, Eleni; Trypaki, Maria; Sfakianaki, Maria; Koutsopoulos, Anastasios; Mavroudis, Dimitris; Stathopoulos, Efstathios; Georgoulias, Vassilis; Souglakos, John

    2013-01-01

    Background The aim of the study was to evaluate the predictive value of genes involved in the action of cisplatin-etoposide in Small Cell Lung Cancer (SCLC). Methods 184 SCLC patients’ primary tumour samples were analyzed for ERCCI, BRCA1, ATP7B, PKM2 TOPOI, TOPOIIA, TOPOIIB and C-MYC mRNA expression. All patients were treated with cisplatin-etoposide. Results The patients’ median age was 63 years and 120 (65%) had extended stage, 75 (41%) had increased LDH serum levels and 131 (71%) an ECOG performance status was 0-1. Patients with limited stage, whose tumours expressed high ERCC1 (p=0.028), PKM2 (p=0.046), TOPOI (p=0.008), TOPOIIA (p=0.002) and TOPOIIB (p<0.001) mRNA had a shorter Progression Free Survival (PFS). In limited stage patients, high expression of ERCC1 (p=0.014), PKM2 (p=0.026), TOPOIIA (p=0.021) and TOPOIIB (p=0.019) was correlated with decreased median overall survival (mOS) while in patients with extended stage, only high TOPOIIB expression had a negative impact on Os (p=0.035). The favorable expression signature expression signature (low expression of ERCC1, PKM2, TOPOIIA and TOPOIIB) was correlated with significantly better PFS and Os in both LS-SCLC (p<0.001 and p=0.007, respectively) and ES-SCLC (p=0.007 and (p=0.011, respectively) group. The unfavorable expression signature was an independent predictor for poor PFS (HR: 3.18; p=0.002 and HR: 3.14; p=0.021) and Os (HR: 4.35; p=0.001and HR: 3.32; p=0.019) in both limited and extended stage, respectively. Conclusions Single gene’s expression analysis as well as the integrated analysis of ERCC1, PKM2, TOPOIIA and TOPOIIB may predict treatment outcome in patients with SCLC. These findings should be further validated in a prospective study. PMID:24058603

  10. 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

  11. 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

  12. A common region of deletion on chromosome 17q in both sporadic and familial epithelial ovarian tumors distal to BRCA1

    SciTech Connect

    Godwin, A.K.; Vanderveer, L.; Schultz, D.C.; Altomare, D.A.; Buetow, K.H.; Daly, M.; Getts, L.A.; Masny, A.; Rosenblum, N.

    1994-10-01

    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 17p13.1 and 17p13.3 markers. When six polymorphic markers flanking the familial breast/ovarian cancer susceptibility locus on 17q12-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 {approximately} 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. 58 refs., 3 figs., 4 tabs.

  13. 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

  14. 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

  15. Androgen Receptor, EGFR, and BRCA1 as Biomarkers in Triple-Negative Breast Cancer: A Meta-Analysis

    PubMed Central

    Zhang, Li; Fang, Cheng; Xu, Xianqun; Li, Anling; Cai, Qing; Long, Xinghua

    2015-01-01

    Objective. More and more evidences demonstrate that androgen receptor (AR), epidermal growth factor receptor (EGFR), and breast cancer susceptibility gene 1 (BRCA1) have unique clinical implications for targeted therapy or prognosis in triple-negative breast cancer (TNBC). Therefore, we conducted a meta-analysis to summarize the possible associations. Methods. We retrieved published articles about AR, EGFR, and BRCA1 in TNBC from PubMed and EMBASE. The analysis was performed with Rev-Man 5.2 software. Results. A total of 38 articles were eligible for the meta-analysis. Our study showed that the expression level of EGFR (OR = 6.88, P < 0.00001) and the prevalence of BRCA1 mutation (RR = 5.26, P < 0.00001) were higher in TNBC than non-TNBC. In contrast, the expression level of AR was lower in TNBC than non-TNBC (OR = 0.07, P < 0.00001). In the subgroup related to EGFR expression, the level of EGFR expression was significantly increased in Asians (OR = 9.60) compared with Caucasians (OR = 5.53) for TNBC patients. Additionally, the prevalence of BRCA1 mutation in Asians (RR = 5.43, P < 0.00001) was higher than that in Caucasians (RR = 5.16, P < 0.00001). Conclusions. The distinct expression of AR and EGFR and the prevalence of BRCA1 mutation indicated that AR, EGFR, and BRCA1 might be unique biomarkers for targeted therapy and prognosis in TNBC. PMID:25695063

  16. Clinical Characteristics of Ovarian Cancer Classified by BRCA1, BRCA2, and RAD51C Status

    PubMed Central

    Cunningham, J. M.; Cicek, M. S.; Larson, N. B.; Davila, J.; Wang, C.; Larson, M. C.; Song, H.; Dicks, E. M.; Harrington, P.; Wick, M.; Winterhoff, B. J.; Hamidi, H.; Konecny, G. E.; Chien, J.; Bibikova, M.; Fan, J.-B.; Kalli, K. R.; Lindor, N. M.; Fridley, B. L.; Pharoah, P. P. D.; Goode, E. L.

    2014-01-01

    We evaluated homologous recombination deficient (HRD) phenotypes in epithelial ovarian cancer (EOC) considering BRCA1, BRCA2, and RAD51C in a large well-annotated patient set. We evaluated EOC patients for germline deleterious mutations (n = 899), somatic mutations (n = 279) and epigenetic alterations (n = 482) in these genes using NGS and genome-wide methylation arrays. Deleterious germline mutations were identified in 32 (3.6%) patients for BRCA1, in 28 (3.1%) for BRCA2 and in 26 (2.9%) for RAD51C. Ten somatically sequenced patients had deleterious alterations, six (2.1%) in BRCA1 and four (1.4%) in BRCA2. Fifty two patients (10.8%) had methylated BRCA1 or RAD51C. HRD patients with germline or somatic alterations in any gene were more likely to be high grade serous, have an earlier diagnosis age and have ovarian and/or breast cancer family history. The HRD phenotype was most common in high grade serous EOC. Identification of EOC patients with an HRD phenotype may help tailor specific therapies. PMID:24504028

  17. The contribution of founder mutations in BRCA1 to breast cancer in Belarus.

    PubMed

    Uglanitsa, N; Oszurek, O; Uglanitsa, K; Savonievich, E; Lubiński, J; Cybulski, C; Debniak, T; Narod, S A; Gronwald, J

    2010-10-01

    Mutations in the BRCA1 gene increase susceptibility to both breast and ovarian cancer. In some countries, including several in Eastern Europe, founder mutations in the BRCA1 gene are responsible for a significant proportion of breast cancer cases. To estimate the hereditary proportion of breast cancer in Belarus, we sought the presence of any of three founder mutations in BRCA1 (4153delA, 5382insC and C61G) in 500 unselected cases of breast cancer. These mutations have previously been identified in breast/ovarian cancer families from Belarus and from other Slavic countries, including Poland and Russia. One of the three founder mutations in BRCA1 was present in 38 of 500 unselected cases of breast cancer (7.6%). A mutation was found in 12.6% of women diagnosed before age 50 and 5.6% of women diagnosed after age 50. A mutation was identified in 2 of 251 newborn controls (0.8%). The hereditary proportion of breast cancers in Belarus is among the highest of any countries studied to date.

  18. Germ-line BRCA1 mutations in selected men with prostate cancer

    SciTech Connect

    Langston, A.A.; Stanford, J.L.; Wicklund, K.G.; Thompson, J.D.; Blazej, R.G.; Ostrander, E.A.

    1996-04-01

    Prostate cancer is the most common malignancy among American men. Although the causes of prostate cancer are unknown, a family history of the disease is one of the strongest risk factors identified, to date. Men with an affected first-degree relative with prostate cancer have at least a two-to-three-fold-higher risk of developing the disease compared with men who have no such family history. Epidemiological observations also suggest a clustering of prostate and breast cancers in some families. More specifically, at least two studies suggest that inherited mutations in highly penetrant dominant genes such as BRCA1, which predisposes women to breast and ovarian cancers, may also be associated with an increased risk of prostate cancer in men. In a study of seven large Icelandic breast cancer families, two of which showed evidence of linkage to BRCA1, prostate cancer was found to be the second most frequent malignancy after breast cancer. Among presumed paternal carriers of mutant breast cancer gene alleles, 44% had a history of prostate cancer. Additional evidence regarding BRCA1 and prostate cancer risk comes from an analysis of 33 BRCA1-linked families. This cooperative study estimated a relative risk of prostate cancer of 3.33 (95% confidence interval 1.8-6.2) among men carrying mutations compared with the general population. 26 refs., 3 tabs.

  19. 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

  20. 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

  1. Direct selection in the BRCA1 region of human chromosome 17q21

    SciTech Connect

    Osborne-Lawrence, S.L.; Welcsh, P.L.; Gallardo, T.D.

    1994-09-01

    Direct cDNA selection was used to obtain candidate genes within the region of human chromosome 17q21 associated with early onset familial breast and ovarian cancer (BRCA1). Four sets of pooled cosmids (10 to 25 per set) derived from this region were used in the selection of cDNAs from four complex human cDNA pools: placenta, fetal head, HeLa cells, and activated T cells. Two YACs within our contig were also used in a separate selection. A reporter gene, estradiol 17 beta-hydroxysteriod dehydrogenase (EDH17B), located on one of the cosmids in the contig of the region, was monitored to observe the efficiency of the selection. A >10,000-fold enrichment of EDH17B was seen after two rounds of selection based on the number of EDH17B clones found in the resultant selected library. Selected inserts were cloned into lambda gt10, amplified with the PCR using vector primers, and dot blotted. 200 inserts have been hybridized individually to cosmids from the contig and to the cDNA dot blots. Approximately 70% of these map back to specific cosmids or YACs in the region. These PCR products were sequenced directly and analyzed for homology against each other as well as against sequences within GenBank. At least 23 new genes have been identified and isolated from this region based on sequence and hybridization overlaps. Seventeen of these cDNAs appear to be unique, two are known genes previously mapped to the region, one has homology to a known known Drosophilia gene, one is homologous to a human non-histone chromosomal protein HMG-17, and two are new members of gene families. These cDNAs are being used for mutational analyses in affected women from families with multiple cases of breast and ovarian cancer.

  2. 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

  3. Low frequency of recurrent BRCA1 and BRCA2 mutations in Spain.

    PubMed

    Llort, Gemma; Muñoz, Carmen Yagüe; Tuser, Mercè Peris; Guillermo, Ignacio Blanco; Lluch, José Ramón Germà; Bale, Allen E; Franco, Mayra Alvarez

    2002-03-01

    BRCA1 and BRCA2 mutations underlie a substantial proportion of all hereditary breast cancer. The mutational spectrum in these genes is very broad, with hundreds of different BRCA mutations reported worldwide. However, high frequency founder mutations make up a substantial fraction of all mutations in some ethnic groups. We directly sequenced BRCA1 and BRCA2 in 35 Spanish breast/ovarian cancer families and found 13 mutations of which 3 had been reported previously in Spain. The ten novel mutations are: IVS5+1 G>A, 1491delA, Leu1086Ter, and Gln895Ter in BRCA1; Glu49Ter, 5373delGTAT, 5947delCTCT, 6672delTA, 8281insA, and Pro3039Leu (which also involves a splice site) in BRCA2. Our data, in combination with previous reports, indicate that 14 mutations have been seen recurrently in Spanish families. Analyzing these 14 mutations in 42 previously untested breast/ovarian cancer families revealed only two families testing positive, one for BRCA1 185delAG and one for BRCA2 9254delATCAT. While several mutations have been found recurrently in Spain, none appear to be high frequency founder mutations based on studies of breast and ovarian cancer families.

  4. 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

  5. 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

  6. DNA Damage Response Genes and the Development of Cancer Metastasis

    PubMed Central

    Broustas, Constantinos G.; Lieberman, Howard B.

    2014-01-01

    DNA damage response genes play vital roles in the maintenance of a healthy genome. Defects in cell cycle checkpoint and DNA repair genes, especially mutation or aberrant downregulation, are associated with a wide spectrum of human disease, including a predisposition to the development of neurodegenerative conditions and cancer. On the other hand, upregulation of DNA damage response and repair genes can also cause cancer, as well as increase resistance of cancer cells to DNA damaging therapy. In recent years, it has become evident that many of the genes involved in DNA damage repair have additional roles in tumorigenesis, most prominently by acting as transcriptional (co-) factors. Although defects in these genes are causally connected to tumor initiation, their role in tumor progression is more controversial and it seems to depend on tumor type. In some tumors like melanoma, cell cycle checkpoint/DNA repair gene upregulation is associated with tumor metastasis, whereas in a number of other cancers the opposite has been observed. Several genes that participate in the DNA damage response, such as RAD9, PARP1, BRCA1, ATM and TP53 have been associated with metastasis by a number of in vitro biochemical and cellular assays, by examining human tumor specimens by immunohistochemistry or by DNA genomewide gene expression profiling. Many of these genes act as transcriptional effectors to regulate other genes implicated in the pathogenesis of cancer. Furthermore, they are aberrantly expressed in numerous human tumors and are causally related to tumorigenesis. However, whether the DNA damage repair function of these genes is required to promote metastasis or another activity is responsible (e.g., transcription control) has not been determined. Importantly, despite some compelling in vitro evidence, investigations are still needed to demonstrate the role of cell cycle checkpoint and DNA repair genes in regulating metastatic phenotypes in vivo. PMID:24397478

  7. 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.

  8. 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.

  9. Skin cancer risk in BRCA1/2 mutation carriers.

    PubMed

    Gumaste, P V; Penn, L A; Cymerman, R M; Kirchhoff, T; Polsky, D; McLellan, B

    2015-06-01

    Women with BRCA1/2 mutations have an elevated risk of breast and ovarian cancer. These patients and their clinicians are often concerned about their risk for other cancers, including skin cancer. Research evaluating the association between BRCA1/2 mutations and skin cancer is limited and has produced inconsistent results. Herein, we review the current literature on the risk of melanoma and nonmelanoma skin cancers in BRCA1/2 mutation carriers. No studies have shown a statistically significant risk of melanoma in BRCA1 families. BRCA2 mutations have been linked to melanoma in large breast and ovarian cancer families, though a statistically significant elevated risk was reported in only one study. Five additional studies have shown some association between BRCA2 mutations and melanoma, while four studies did not find any association. With respect to nonmelanoma skin cancers, studies have produced conflicting results. Given the current state of medical knowledge, there is insufficient evidence to warrant increased skin cancer surveillance of patients with a confirmed BRCA1/2 mutation or a family history of a BRCA1/2 mutation, in the absence of standard risk factors. Nonetheless, suspected BRCA1/2 mutation carriers should be counselled about skin cancer risks and may benefit from yearly full skin examinations.

  10. The prevalence of BRCA1 mutations in Chinese patients with early onset breast cancer and affected relatives

    PubMed Central

    Sng, J-H; Chang, J; Feroze, F; Rahman, N; Tan, W; Lim, S; Lehnert, M; Pool, S van der; Wong, J

    2000-01-01

    The purpose of this study was to determine the prevalence of BRCA1 mutations in Chinese breast cancer patients in Singapore. BRCA1 analysis was conducted in consecutive patients with breast cancer before the age of 40 years (76 women), or whose relatives had breast or ovarian cancer (16 women). Ten patients had both early onset breast cancer and affected relatives. Genomic DNA from peripheral mononuclear blood cells was studied by using the protein transcription–translation assay (exon 11) and single-strand conformational polymorphism, with subsequent DNA sequencing. All six disease-causing mutations occurred in women under 40 years (8.6%) with three occurring in patients under 35 years (three out of 22 patients, 13.6%). Mis-sense mutations of unknown significance were found in three patients. Two of the ten women with affected relatives under 40 years had BRCA1 mutations. The prevalence of BRCA1 mutations in Chinese patients with early onset breast cancer is similar to that observed in Caucasian women. Most Chinese patients with affected relatives were not carriers of BRCA1 mutations. © 2000 Cancer Research Campaign PMID:10682662

  11. A risk prediction algorithm for ovarian cancer incorporating BRCA1, BRCA2, common alleles and other familial effects

    PubMed Central

    Jervis, Sarah; Song, Honglin; Lee, Andrew; Dicks, Ed; Harrington, Patricia; Baynes, Caroline; Manchanda, Ranjit; Easton, Douglas F; Jacobs, Ian; Pharoah, Paul P D; Antoniou, Antonis C

    2015-01-01

    Background Although BRCA1 and BRCA2 mutations account for only ∼27% of the familial aggregation of ovarian cancer (OvC), no OvC risk prediction model currently exists that considers the effects of BRCA1, BRCA2 and other familial factors. Therefore, a currently unresolved problem in clinical genetics is how to counsel women with family history of OvC but no identifiable BRCA1/2 mutations. Methods We used data from 1548 patients with OvC and their relatives from a population-based study, with known BRCA1/2 mutation status, to investigate OvC genetic susceptibility models, using segregation analysis methods. Results The most parsimonious model included the effects of BRCA1/2 mutations, and the residual familial aggregation was accounted for by a polygenic component (SD 1.43, 95% CI 1.10 to 1.86), reflecting the multiplicative effects of a large number of genes with small contributions to the familial risk. We estimated that 1 in 630 individuals carries a BRCA1 mutation and 1 in 195 carries a BRCA2 mutation. We extended this model to incorporate the explicit effects of 17 common alleles that are associated with OvC risk. Based on our models, assuming all of the susceptibility genes could be identified we estimate that the half of the female population at highest genetic risk will account for 92% of all OvCs. Conclusions The resulting model can be used to obtain the risk of developing OvC on the basis of BRCA1/2, explicit family history and common alleles. This is the first model that accounts for all OvC familial aggregation and would be useful in the OvC genetic counselling process. PMID:26025000

  12. 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

  13. Evaluation of the Dutch BRCA1/2 clinical genetic center referral criteria in an unselected early breast cancer population.

    PubMed

    van den Broek, Alexandra J; de Ruiter, Karen; van 't Veer, Laura J; Tollenaar, Rob A E M; van Leeuwen, Flora E; Verhoef, Senno; Schmidt, Marjanka K

    2015-05-01

    In this study, we evaluated the diagnostic value of the Dutch Clinical Genetic Center (CGC) referral guidelines for BRCA1/2 mutation testing in 903 early breast cancer patients, unselected for family history, diagnosed in a cancer hospital before the age of 50 years in 1974-2002; most prevalent Dutch pathogenic BRCA1/2 mutations had been analyzed on coded DNA in a research setting. Forty-nine (5.4%) of the patients were proven to be BRCA1/2 mutation carriers. We found that 78% and 69% of BRCA1 and BRCA2 mutation carriers identified met the criteria for referral to the CGC based on age, family history and synchronous multiple tumors; reflected by a combined sensitivity of 75.5% and specificity of 63.2%. More than half of the BRCA1 mutation carriers, that is, 58% had a triple-negative tumor. The highest AUC was obtained by shifting the age at diagnosis threshold criterion from 40 to 35 years and by adding a 'triple-negative breast cancer' criterion with an age threshold of 45 years; the specificity increased to 71.2%, whereas the sensitivity remained the same; that is, a referral of fewer patients will lead to the identification of at least the same number of BRCA1/2 mutation carriers. Two-thirds of the BRCA1/2 mutation carriers identified in this research setting had been referred for counseling and testing. Our results indicate that, awaiting a possibly more extended mutation screening of all breast cancer patients, the triple-negative status of a breast cancer should be added to the CGC referral criteria.

  14. Generation of a transcription map from the 17q21 region containing the BRCA1 locus

    SciTech Connect

    Rommens, J.M.; McArthur, J.; Allen, T.

    1994-09-01

    A limited interval of the chromosome 17q21 has been implicated in hereditary breast and ovarian cancer by linkage analysis. The type I 17{beta}-hydroxysteriod dehydrogenase gene (17{beta}HSD) was used to isolate two YACs. These and additional YACs identified with nearby genetic markers were characterized to obtain a detailed physical map of the BRCA1 region. This map provided the basis for the generation of a transcription map in order to identify candidate genes that could be assessed for involvement in the development of breast cancer in affected families. Direct selection of cDNAs from the genomic clones was carried out by hybridization with primary cDNA pools that had been prepared from RNA of mammary gland, ovary, placenta and the Caco-2 colon carcinoma cell line. The selected material was amplified by the polymerase chain reaction and cloned into plasmid vectors. Individual clones of the libraries of the retrieved fragments were then characterized by physical mapping, by RNA hybridization and by sequence analysis. To date, 36 unique cDNA fragments have been mapped to this region and confirmed to originate from chromosome 17. Longer cDNAs were also isolated by screening libraries derived from human breast and placenta. Based on analyses of these clones we have evidence for at least 12 genes from a 1 Megabase region. These include the type I 17{beta}HSD gene and the human {gamma}-tubulin gene. Sequences of two of the cDNA fragments showed similarity to a human brain cDNA and to a human pancreas cDNA. The predicted coding portion of one cDNA showed similarity with a rat ribosomal protein. Also, one cDNA fragment was found to be part of the recently identified gene corresponding to the CA125 antigen. The sequences of the remaining clones showed no strong similarity to known genes or proteins. These cDNAs are being analyzed by DNA and RNA hybridization for aberrations in breast and ovarian cancers.

  15. 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

  16. NPR3 protects cardiomyocytes from apoptosis through inhibition of cytosolic BRCA1 and TNF-α

    PubMed Central

    Lin, Dong; Chai, Yubo; Izadpanah, Reza; Braun, Stephen E.; Alt, Eckhard

    2016-01-01

    ABSTRACT Natriuretic peptide receptor 3 (NPR3) is a clearance receptor by binding and internalizing natriuretic peptides (NPs) for ultimate degradation. Patients with cardiac failure show elevated NPs. NPs are linked to poor long-term survival because of their apoptotic effects. However, the underling mechanisms have not been identified yet. Here we report the role of NPR3 in anti-apoptosis via the breast cancer type 1 susceptibility protein (BRCA1) and tumor necrosis factor α (TNF-α ). To demonstrate a role for NPR3 in apoptosis, stable H9C2 cardiomyocyte cell lines using shRNA to knockdown NPR3 were generated. The activities of caspase-3, 8, and 9 were significantly increased in NPR3 knockdown H9C2 cardiomyocytes. Knockdown of NPR3 increased the expression of BRCA1. Also NPR3 knockdown remarkably increased the activity of cAMP response element-binding protein (CREB), a positive regulatory element for BRCA1 expression. BRCA1 showed dispersed nuclear localization in non-cardiomyocytes while predominantly cytoplasmic localization in H9C2 cells. Meanwhile, NPR3 knockdown significantly increased TNF-α gene expression. These data show that NPR3 knockdown in H9C2 cells triggered both extrinsic and intrinsic apoptotic pathways. NPR3 protects cardiomyocytes from apoptosis through inhibition of cytosolic BRCA1 and TNF-α, which are regulators of apoptosis. Our studies demonstrate anti-apoptosis role of NPR3 in protecting cardiomyocytes and establish the first molecular link between NP system and programmed cell death. PMID:27494651

  17. Long Term Outcomes of BRCA1/BRCA2 Testing: Risk Reduction and Surveillance

    PubMed Central

    Schwartz, Marc D.; Isaacs, Claudine; Graves, Kristi D.; Poggi, Elizabeth; Peshkin, Beth N.; Gell, Christy; Finch, Clinton; Kelly, Scott; Taylor, Kathryn L.; Perley, Lauren

    2012-01-01

    Purpose For BRCA1/BRCA2 gene testing to benefit public health, mutation carriers must initiate appropriate risk management strategies. There has been little research examining the long-term use and prospective predictors of the full range of risk management behaviors among women who have undergone BRCA1/2 testing. We evaluated long-term uptake and predictors of risk reducing mastectomy (RRM), risk reducing oophorectomy (RRBSO), chemoprevention and cancer screening among women at a mean of 5.3 years post testing. Patients and Methods Participants were 465 women who underwent BRCA1/2 testing. Prior to genetic counseling, we measured family/personal cancer history, sociodemographics, perceived risk, cancer-specific and general distress. We contacted patients at a mean of 5.3-years post-testing to measure use of: RRM; RRBSO; chemoprevention; breast and ovarian cancer screening. Results Among participants with intact breasts and/or ovaries at the time of testing, BRCA1/2 carriers were significantly more likely to obtain RRM (37%) and RRBSO (65%) compared to women who received uninformative (RRM=6.8%; RRBSO=13.3%) or negative (RRM=0%; RRBSO=1.9%) results. Among carriers, pre-counseling anxiety was associated with subsequent uptake of RRM. RRO was predicted by age. Carriers were also more likely have used breast cancer chemoprevention and have obtained a screening MRI. Conclusion This prospective evaluation of the uptake and predictors of long-term management outcomes provides a clearer picture of decision making in this population. By a mean of 5.3 years post-testing, more than 80% of carriers had obtained RRM, RRBSO or both, suggesting that BRCA1/2 testing is likely to favorably impact breast and ovarian cancer outcomes. PMID:21717445

  18. CAF-like state in primary skin fibroblasts with constitutional BRCA1 epimutation sheds new light on tumor suppressor deficiency-related changes in healthy tissue.

    PubMed

    Etzold, Anna; Galetzka, Danuta; Weis, Eva; Bartsch, Oliver; Haaf, Thomas; Spix, Claudia; Itzel, Timo; Schweiger, Susann; Strand, Dennis; Strand, Susanne; Zechner, Ulrich

    2016-01-01

    Constitutive epimutations of tumor suppressor genes are increasingly considered as cancer predisposing factors equally to sequence mutations. In light of the emerging role of the microenvironment for cancer predisposition, initiation, and progression, we aimed to characterize the consequences of a BRCA1 epimutation in cells of mesenchymal origin. We performed a comprehensive molecular and cellular comparison of primary dermal fibroblasts taken from a monozygous twin pair discordant for recurrent cancers and BRCA1 epimutation, whose exceptional clinical case we previously reported in this journal. Comparative transcriptome analysis identified differential expression of extracellular matrix-related genes and pro-tumorigenic growth factors, such as collagens and CXC chemokines. Moreover, genes known to be key markers of so called cancer-associated fibroblasts (CAFs), such as ACTA2, FAP, PDPN, and TNC, were upregulated in fibroblasts of the affected twin (BRCA1(mosMe)) in comparison to those of the healthy twin (BRCA1(wt)). Further analyses detected CAF-typical cellular features, including an elevated growth rate, enhanced migration, altered actin architecture and increased production of ketone bodies in BRCA1(mosMe) fibroblasts compared to BRCA1(wt) fibroblasts. In addition, conditioned medium of BRCA1(mosMe) fibroblasts was more potent than conditioned medium of BRCA1(wt) fibroblasts to promote cell proliferation in an epithelial and a cancer cell line. Our data demonstrate, that a CAF-like state is not an exclusive feature of tumor-associated tissue but also exists in healthy tissue with tumor suppressor deficiency. The naturally occurring phenomenon of twin fibroblasts differing in their BRCA1 methylation status revealed to be a unique powerful tool for exploring tumor suppressor deficiency-related changes in healthy tissue, reinforcing their significance for cancer predisposition.

  19. CAF-like state in primary skin fibroblasts with constitutional BRCA1 epimutation sheds new light on tumor suppressor deficiency-related changes in healthy tissue.

    PubMed

    Etzold, Anna; Galetzka, Danuta; Weis, Eva; Bartsch, Oliver; Haaf, Thomas; Spix, Claudia; Itzel, Timo; Schweiger, Susann; Strand, Dennis; Strand, Susanne; Zechner, Ulrich

    2016-01-01

    Constitutive epimutations of tumor suppressor genes are increasingly considered as cancer predisposing factors equally to sequence mutations. In light of the emerging role of the microenvironment for cancer predisposition, initiation, and progression, we aimed to characterize the consequences of a BRCA1 epimutation in cells of mesenchymal origin. We performed a comprehensive molecular and cellular comparison of primary dermal fibroblasts taken from a monozygous twin pair discordant for recurrent cancers and BRCA1 epimutation, whose exceptional clinical case we previously reported in this journal. Comparative transcriptome analysis identified differential expression of extracellular matrix-related genes and pro-tumorigenic growth factors, such as collagens and CXC chemokines. Moreover, genes known to be key markers of so called cancer-associated fibroblasts (CAFs), such as ACTA2, FAP, PDPN, and TNC, were upregulated in fibroblasts of the affected twin (BRCA1(mosMe)) in comparison to those of the healthy twin (BRCA1(wt)). Further analyses detected CAF-typical cellular features, including an elevated growth rate, enhanced migration, altered actin architecture and increased production of ketone bodies in BRCA1(mosMe) fibroblasts compared to BRCA1(wt) fibroblasts. In addition, conditioned medium of BRCA1(mosMe) fibroblasts was more potent than conditioned medium of BRCA1(wt) fibroblasts to promote cell proliferation in an epithelial and a cancer cell line. Our data demonstrate, that a CAF-like state is not an exclusive feature of tumor-associated tissue but also exists in healthy tissue with tumor suppressor deficiency. The naturally occurring phenomenon of twin fibroblasts differing in their BRCA1 methylation status revealed to be a unique powerful tool for exploring tumor suppressor deficiency-related changes in healthy tissue, reinforcing their significance for cancer predisposition. PMID:26949839

  20. 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.

  1. 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

  2. [Genotyping of BRCA1, BRCA2 and CHEK2 germline mutations in Russian breast cancer patients using diagnostic biochips].

    PubMed

    Nasedkina, T V; Gromyko, O E; Emel'ianova, M A; Ignatova, E O; Kazubskaia, T P; Portnoĭ, S M; Zasedatelev, A S; Liubchenko, L N

    2014-01-01

    Germline mutations of BRCA1/2 genes cause the predisposition of their carriers to breast or/and ovary cancers (BC or/and OC) during the lifetime. Identification of these mutations is a basis of molecular diagnosis for BC susceptibility. Rapid genotyping technique using microarrays for identification of BRCA1 185delAG, 300T>G, 4153delA, 5382insC mutations and 4158 A>G sequence variant; BRCA2 695insT and 6174delT mutations; 1100delC mutation in CHEK2 gene was applied for 412 randomly collected breast cancer samples from the central region of European area of Russia. In 25 (6.0%) patients (6.0%) BC was associated with other tumours: OC, cervical cancer, colorectal cancer etc. BRCA1/2 and CHEK2 mutations were found in 33 (8.0%) BC patients. The most frequent mutation was BRCA1 5382insC, occurred in 16 (3.9%) BC patients, and CHEK2 1100delC, revealed in 7 (1.7%) BC patients. An application of diagnostic BC-microarray for genetic testing of BRCA1/2 and CHEK2 founder mutations has been discussed. PMID:25850293

  3. Polymorphisms in DNA Repair Genes and MDR1 and the Risk for Non-Hodgkin Lymphoma

    PubMed Central

    Kim, Hee Nam; Kim, Nan Young; Yu, Li; Kim, Yeo-Kyeoung; Lee, Il-Kwon; Yang, Deok-Hwan; Lee, Je-Jung; Shin, Min-Ho; Park, Kyeong-Soo; Choi, Jin-Su; Kim, Hyeoung-Joon

    2014-01-01

    The damage caused by oxidative stress and exposure to cigarette smoke and alcohol necessitate DNA damage repair and transport by multidrug resistance-1 (MDR1). To explore the association between polymorphisms in these genes and non-Hodgkin lymphoma risk, we analyzed 15 polymorphisms of 12 genes in a population-based study in Korea (694 cases and 1700 controls). Four genotypes of DNA repair pathway genes (XRCC1 399 GA, OGG1 326 GG, BRCA1 871 TT, and WRN 787 TT) were associated with a decreased risk for NHL [odds ratio (OR)XRCC1 GA = 0.80, p = 0.02; OROGG1 GG = 0.70, p = 0.008; ORBRCA1 TT = 0.71, p = 0.048; ORWRN TT = 0.68, p = 0.01]. Conversely, the MGMT 115 CT genotype was associated with an increased risk for NHL (OR = 1.25, p = 0.04). In the MDR1 gene, the 1236 CC genotype was associated with a decreased risk for NHL (OR = 0.74, p = 0.04), and the 3435 CT and TT genotypes were associated with an increased risk (OR3435CT = 1.50, p < 0.0001; OR3435TT = 1.43, p = 0.02). These results suggest that polymorphisms in the DNA repair genes XRCC1, OGG1, BRCA1, WRN1, and MGMT and in the MDR1 gene may affect the risk for NHL in Korean patients. PMID:24756092

  4. Polymorphisms in DNA repair genes and MDR1 and the risk for non-Hodgkin lymphoma.

    PubMed

    Kim, Hee Nam; Kim, Nan Young; Yu, Li; Kim, Yeo-Kyeoung; Lee, Il-Kwon; Yang, Deok-Hwan; Lee, Je-Jung; Shin, Min-Ho; Park, Kyeong-Soo; Choi, Jin-Su; Kim, Hyeoung-Joon

    2014-04-21

    The damage caused by oxidative stress and exposure to cigarette smoke and alcohol necessitate DNA damage repair and transport by multidrug resistance-1 (MDR1). To explore the association between polymorphisms in these genes and non-Hodgkin lymphoma risk, we analyzed 15 polymorphisms of 12 genes in a population-based study in Korea (694 cases and 1700 controls). Four genotypes of DNA repair pathway genes (XRCC1 399 GA, OGG1 326 GG, BRCA1 871 TT, and WRN 787 TT) were associated with a decreased risk for NHL [odds ratio (OR)XRCC1 GA=0.80, p=0.02; OROGG1 GG=0.70, p=0.008; ORBRCA1 TT=0.71, p=0.048; ORWRN TT=0.68, p=0.01]. Conversely, the MGMT 115 CT genotype was associated with an increased risk for NHL (OR=1.25, p=0.04). In the MDR1 gene, the 1236 CC genotype was associated with a decreased risk for NHL (OR=0.74, p=0.04), and the 3435 CT and TT genotypes were associated with an increased risk (OR3435CT=1.50, p<0.0001; OR3435TT=1.43, p=0.02). These results suggest that polymorphisms in the DNA repair genes XRCC1, OGG1, BRCA1, WRN1, and MGMT and in the MDR1 gene may affect the risk for NHL in Korean patients.

  5. A Mouse Model That Reproduces the Developmental Pathways and Site Specificity of the Cancers Associated With the Human BRCA1 Mutation Carrier State

    PubMed Central

    Liu, Ying; Yen, Hai-Yun; Austria, Theresa; Pettersson, Jonas; Peti-Peterdi, Janos; Maxson, Robert; Widschwendter, Martin; Dubeau, Louis

    2015-01-01

    Predisposition to breast and extrauterine Müllerian carcinomas in BRCA1 mutation carriers is due to a combination of cell-autonomous consequences of BRCA1 inactivation on cell cycle homeostasis superimposed on cell-nonautonomous hormonal factors magnified by the effects of BRCA1 mutations on hormonal changes associated with the menstrual cycle. We used the Müllerian inhibiting substance type 2 receptor (Mis2r) promoter and a truncated form of the Follicle stimulating hormone receptor (Fshr) promoter to introduce conditional knockouts of Brca1 and p53 not only in mouse mammary and Müllerian epithelia, but also in organs that control the estrous cycle. Sixty percent of the double mutant mice developed invasive Müllerian and mammary carcinomas. Mice carrying heterozygous mutations in Brca1 and p53 also developed invasive tumors, albeit at a lesser (30%) rate, in which the wild type alleles were no longer present due to loss of heterozygosity. While mice carrying heterozygous mutations in both genes developed mammary tumors, none of the mice carrying only a heterozygous p53 mutation developed such tumors (P < 0.0001), attesting to a role for Brca1 mutations in tumor development. This mouse model is attractive to investigate cell-nonautonomous mechanisms associated with cancer predisposition in BRCA1 mutation carriers and to investigate the merit of chemo-preventive drugs targeting such mechanisms. PMID:26629527

  6. A Mouse Model That Reproduces the Developmental Pathways and Site Specificity of the Cancers Associated With the Human BRCA1 Mutation Carrier State.

    PubMed

    Liu, Ying; Yen, Hai-Yun; Austria, Theresa; Pettersson, Jonas; Peti-Peterdi, Janos; Maxson, Robert; Widschwendter, Martin; Dubeau, Louis

    2015-10-01

    Predisposition to breast and extrauterine Müllerian carcinomas in BRCA1 mutation carriers is due to a combination of cell-autonomous consequences of BRCA1 inactivation on cell cycle homeostasis superimposed on cell-nonautonomous hormonal factors magnified by the effects of BRCA1 mutations on hormonal changes associated with the menstrual cycle. We used the Müllerian inhibiting substance type 2 receptor (Mis2r) promoter and a truncated form of the Follicle stimulating hormone receptor (Fshr) promoter to introduce conditional knockouts of Brca1 and p53 not only in mouse mammary and Müllerian epithelia, but also in organs that control the estrous cycle. Sixty percent of the double mutant mice developed invasive Müllerian and mammary carcinomas. Mice carrying heterozygous mutations in Brca1 and p53 also developed invasive tumors, albeit at a lesser (30%) rate, in which the wild type alleles were no longer present due to loss of heterozygosity. While mice carrying heterozygous mutations in both genes developed mammary tumors, none of the mice carrying only a heterozygous p53 mutation developed such tumors (P < 0.0001), attesting to a role for Brca1 mutations in tumor development. This mouse model is attractive to investigate cell-nonautonomous mechanisms associated with cancer predisposition in BRCA1 mutation carriers and to investigate the merit of chemo-preventive drugs targeting such mechanisms.

  7. 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.

  8. Detection of BRCA1 and BRCA2 Ashkenazi Jewish founder mutations in formalin-fixed paraffin-embedded tissues using conventional PCR and heteroduplex/amplicon size differences.

    PubMed

    Mangold, Kathy A; Wang, Vivien; Weissman, Scott M; Rubinstein, Wendy S; Kaul, Karen L

    2010-01-01

    In many families with histories suggestive of BRCA1- or BRCA2-related disease, the proband is deceased. Reliable assessment of archived tissue blocks not amenable to full gene sequencing would be helpful. In this study, a polymerase chain reaction (PCR) assay using primers that bracket the BRCA mutation site and microfluidics-based detection of heteroduplex/amplicon size differences was developed to circumvent artifacts associated with low quality DNA from formalin-fixed paraffin-embedded (FFPE) tissue. Genomic DNA was extracted from 100 FFPE specimens from patients that had previously undergone BRCA gene sequence analysis on blood specimens. Conventional PCR amplification products were differentiated using the Agilent 2100 Bioanalyzer. One FFPE specimen failed to amplify the wild-type alleles for all three sites and was therefore called indeterminate. All 62 FFPE specimens with known Ashkenazi Jewish founder mutations had both the wild-type and the correct mutated allele amplified, including one specimen that failed to amplify the mutant allele in other real-time PCR assays. Appropriately, 21 FFPE specimens known to have other BRCA1/2 mutations and 16 without any mutation had only the wild-type allele correctly amplified for each target. Therefore, by changing the primer location and detecting amplicons via heteroduplexes formed by size differences, we identified mutations from FFPE tissues missed using real-time methods.

  9. 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

  10. Mutation screening of MIR146A/B and BRCA1/2 3'-UTRs in the GENESIS study.

    PubMed

    Garcia, Amandine I; Buisson, Monique; Damiola, Francesca; Tessereau, Chloé; Barjhoux, Laure; Verny-Pierre, Carole; Sornin, Valérie; Dondon, Marie-Gabrielle; Eon-Marchais, Séverine; Caron, Olivier; Gautier-Villars, Marion; Coupier, Isabelle; Buecher, Bruno; Vennin, Philippe; Belotti, Muriel; Lortholary, Alain; Gesta, Paul; Dugast, Catherine; Noguès, Catherine; Fricker, Jean-Pierre; Faivre, Laurence; Stoppa-Lyonnet, Dominique; Andrieu, Nadine; Sinilnikova, Olga M; Mazoyer, Sylvie

    2016-08-01

    Although a wide number of breast cancer susceptibility alleles associated with various levels of risk have been identified to date, about 50% of the heritability is still missing. Although the major BRCA1 and BRCA2 genes are being extensively screened for truncating and missense variants in breast and/or ovarian cancer families, potential regulatory variants affecting their expression remain largely unexplored. In an attempt to identify such variants, we focused our attention on gene regulation mediated by microRNAs (miRs). We screened two genes, MIR146A and MIR146B, producing miR-146a and miR-146b-5p, respectively, that regulate BRCA1, and the 3'- untranslated regions (3'-UTRs) of BRCA1 and BRCA2 in the GENESIS French national case/control study (BRCA1- and BRCA2-negative breast cancer cases with at least one sister with breast cancer and matched controls). We identified one rare variant in MIR146A, four in MIR146B, five in BRCA1 3'-UTR and one in BRCA2 3'-UTR in 716 index cases and 619 controls. Among these 11 rare variants, 7 were identified each in 1 index case. None of the three relevant MIR146A/MIR146B variants affected the pre-miR sequences. The potential causality of the four relevant BRCA1/BRCA2 3'-UTRs variants was evaluated with luciferase reporter assays and co-segregation studies, as well as with bioinformatics analyses to predict miRs-binding sites, RNA secondary structures and RNA accessibility. This is the first study to report the screening of miR genes and of BRCA2 3'-UTR in a large series of familial breast cancer cases. None of the variant identified in this study gave convincing evidence of potential pathogenicity.

  11. Progesterone receptor A stability is mediated by glycogen synthase kinase-3β in the Brca1-deficient mammary gland.

    PubMed

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

    2013-09-01

    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-A(S390A) 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.

  12. Cardiac function in BRCA1/2 mutation carriers with history of breast cancer treated with anthracyclines.

    PubMed

    Barac, Ana; Lynce, Filipa; Smith, Karen L; Mete, Mihriye; Shara, Nawar M; Asch, Federico M; Nardacci, Madeline P; Wray, Lynette; Herbolsheimer, Pia; Nunes, Raquel A; Swain, Sandra M; Warren, Robert; Peshkin, Beth N; Isaacs, Claudine

    2016-01-01

    Animal data suggest that defects in BRCA1/2 genes significantly increase the risk of heart failure and mortality in mice exposed to doxorubicine. Women with BRCA1/2 mutations who develop breast cancer (BC) may receive anthracyclines but their risk of cardiac dysfunction has not been investigated. Our study tested the hypothesis that women with history of BRCA1/2 mutation-associated BC treated with anthracyclines have impaired parameters of cardiac function compared to similarly treated women with history of sporadic BC. Women with history of BC and anthracycline treatment underwent an echocardiographic exam for assessment of primary outcomes, left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS). The sample size of 81 provided 79 % power with two-sided two-sample t test and alpha of 0.05 to detect a clinically meaningful difference in cardiac function of absolute 5 % points difference for LVEF and 2 % points difference for GLS. Of 81 normotensive participants, 39 were BRCA1/2 mutation carriers and 42 in the sporadic group. Mean age was 50 ± 9 years in both groups (P = 0.99) but BRCA1/2 mutation carriers had longer anthracycline treatment-to-enrollment time (7.5 ± 5.3 vs. 4.2 ± 3.3 years, P = 0.001). There were no significant differences in LVEF (P = 0.227) or GLS (P = 0.53) between the groups. LVEF was normal in 91 % of women and subclinical cardiac dysfunction defined as absolute GLS value <18.9 % was seen in 4 (10 %) BRCA1/2 mutation carriers and 7 (17 %) sporadic participants. In this first prospective examination of cardiac function in BRCA1/2 mutation carriers, we found no significant differences in sensitive echocardiographic parameters of cardiac function between BRCA1/2 mutation carriers and women with history of sporadic BC who received anthracycline treatment. In contrast to laboratory animal data, our findings indicate lack of elevated cardiac risk with the use of standard-doses of adjuvant anthracyclines in treatment of BRCA1

  13. 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

    2016-02-08

    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.

  14. Mutations in BRCA1 from fixed, paraffin-embedded tissue can be artifacts of preservation.

    PubMed

    Wong, C; DiCioccio, R A; Allen, H J; Werness, B A; Piver, M S

    1998-11-01

    DNA isolated from paraffin-embedded tissues has been used for analysis of DNA alterations in disease states. Use of archival tissue can expedite the gathering of large numbers of specimens from rare disease subtypes that would take years to accumulate prospectively. Therefore, archival tissues from 70 ovarian cancer cases diagnosed before or at age 40 were retrieved for analysis of BRCA1 mutations. DNA was isolated from paraffin-embedded tissue of 70 ovarian cancer cases diagnosed before or at age 40. BRCA1 mutation analysis was conducted by single-strand conformation polymorphism analysis and DNA sequencing. Fifty-eight BRCA1 mutations were found in 34 of the 70 ovarian cancer cases. Twenty-two cases had one mutation each and 12 cases had multiple mutations. Multiple mutations found in histologically normal tissue of 2 cases were not present in matched tumor tissue. For another case, DNA from two separate blocks of normal tissue contained different mutations. These observations were anomalous and suggested that mutations detected in fixed tissues may be artifacts of tissue preservation and not present in the original unfixed tissues. To test this suggestion, blood was obtained from 2 patients for whom mutations were found in fixed, normal tissue. DNA from their unfixed lymphocytes did not contain the mutations found in fixed normal tissue. Thus, mutations found in fixed, paraffin-embedded tissues can be artifacts of tissue preservation. The reliability of DNA sequence data derived from such tissues must be questioned in the absence of corroborating data from unfixed tissues. This severely limits the use of fixed tissues as a source of DNA for retrospective research and for clinical genetic testing in families for which a disease-affected member is not alive.

  15. The Impact of Social Roles on the Experience of Men in BRCA1/2 Families: Implications for Counseling

    PubMed Central

    Daly, Mary B.

    2008-01-01

    Recent advances in genetics have identified several genes associated with inherited susceptibility to breast and ovarian cancer and have led to the commercial availability of mutation analyses. Although the majority of cancers associated with BRCA1/2 mutations are seen in women, men with BRCA1/2 mutations are at increased risk for male breast cancer, prostate cancer, pancreatic cancer and melanoma. Limited data available on the response of men in BRCA1/2 families suggest that the majority do not pursue genetic counseling, thus they may forgo the opportunity to improve health practices and to pass on valuable cancer risk information to offspring. The patterns of relationships of men within the family and society can pose challenges to their recognition of genetic health threats and the need for preventive interventions. Genetic counselors are in a position to inform at-risk males of their genetic risk, and to help them explore their personal health options. PMID:18688698

  16. 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 ...

  17. Development and Characterization of Reference Materials for MTHFR, SERPINA1, RET, BRCA1, and BRCA2 Genetic Testing

    PubMed Central

    Barker, Shannon D.; Bale, Sherri; Booker, Jessica; Buller, Arlene; Das, Soma; Friedman, Kenneth; Godwin, Andrew K.; Grody, Wayne W.; Highsmith, Edward; Kant, Jeffery A.; Lyon, Elaine; Mao, Rong; Monaghan, Kristin G.; Payne, Deborah A.; Pratt, Victoria M.; Schrijver, Iris; Shrimpton, Antony E.; Spector, Elaine; Telatar, Milhan; Toji, Lorraine; Weck, Karen; Zehnbauer, Barbara; Kalman, Lisa V.

    2009-01-01

    Well-characterized reference materials (RMs) are integral in maintaining clinical laboratory quality assurance for genetic testing. These RMs can be used for quality control, monitoring of test performance, test validation, and proficiency testing of DNA-based genetic tests. To address the need for such materials, the Centers for Disease Control and Prevention established the Genetic Testing Reference Material Coordination Program (GeT-RM), which works with the genetics community to improve public availability of characterized RMs for genetic testing. To date, the GeT-RM program has coordinated the characterization of publicly available genomic DNA RMs for a number of disorders, including cystic fibrosis, Huntington disease, fragile X, and several genetic conditions with relatively high prevalence in the Ashkenazi Jewish population. Genotypic information about a number of other cell lines has been collected and is also available. The present study includes the development and commutability/genotype characterization of 10 DNA samples for clinically relevant mutations or sequence variants in the following genes: MTHFR; SERPINA1; RET; BRCA1; and BRCA2. DNA samples were analyzed by 19 clinical genetic laboratories using a variety of assays and technology platforms. Concordance was 100% for all samples, with no differences observed between laboratories using different methods. All DNA samples are available from Coriell Cell Repositories and characterization information can be found on the GeT-RM website. PMID:19767587

  18. 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

  19. 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. |

  20. 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

  1. 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

  2. Implementing a telephone based peer support intervention for women with a BRCA1/2 mutation.

    PubMed

    Farrelly, Ashley; White, Victoria; Young, Mary-Anne; Jefford, Michael; Ieropoli, Sandra; Duffy, Jessica; Winship, Ingrid; Meiser, Bettina

    2015-09-01

    Women with a BRCA1/2 gene mutation face complex risk management decisions and communication issues that can lead to increased levels of distress and unmet needs. We describe the implementation of a peer-support program that aims to reduce distress among women with a BRCA1/2 mutation, including peer and support recipient satisfaction with the program, challenges and lessons learnt. Participants with a BRCA1/2 mutation were matched with a trained peer volunteer (also a mutation carrier) to have regular one-on-one phone calls, over 4 months. Details of the calls, including topics discussed, time spent and number, were collected. Peers and recipients completed surveys assessing how they felt the contact went, satisfaction with the program, and preferences for matching. Satisfaction with the program was high for both peers and recipients. 80% of pairs ended contact through mutual agreement. Peers and recipients differed in the importance placed on age and surgery experience to determine matches. The most challenging aspect of the program for peers was difficulty in contacting recipients. Peer support for women with a BRCA1/2 mutation is feasible. However, to encourage continued involvement by peers and recipients greater flexibility in the method and delivery of contact is needed. We advocate the use of text-messaging and/or email as mechanisms for pairs to arrange and maintain contact. These strategies should be in addition to, rather than replacing, calls. A mixed medium intervention, where recipients can tailor the method of communication to suit their needs, may be preferable and effective, though this would need to be tested.

  3. Breast and Ovarian Cancer Risk and Risk Reduction in Jewish BRCA1/2 Mutation Carriers

    PubMed Central

    Finkelman, Brian S.; Rubinstein, Wendy S.; Friedman, Sue; Friebel, Tara M.; Dubitsky, Shera; Schonberger, Niecee Singer; Shoretz, Rochelle; Singer, Christian F.; Blum, Joanne L.; Tung, Nadine; Olopade, Olufunmilayo I.; Weitzel, Jeffrey N.; Lynch, Henry T.; Snyder, Carrie; Garber, Judy E.; Schildkraut, Joellen; Daly, Mary B.; Isaacs, Claudine; Pichert, Gabrielle; Neuhausen, Susan L.; Couch, Fergus J.; van't Veer, Laura; Eeles, Rosalind; Bancroft, Elizabeth; Evans, D. Gareth; Ganz, Patricia A.; Tomlinson, Gail E.; Narod, Steven A.; Matloff, Ellen; Domchek, Susan; Rebbeck, Timothy R.

    2012-01-01

    Purpose Mutations in BRCA1/2 dramatically increase the risk of both breast and ovarian cancers. Three mutations in these genes (185delAG, 5382insC, and 6174delT) occur at high frequency in Ashkenazi Jews. We evaluated how these common Jewish mutations (CJMs) affect cancer risks and risk reduction. Methods Our cohort comprised 4,649 women with disease-associated BRCA1/2 mutations from 22 centers in the Prevention and Observation of Surgical End Points Consortium. Of these women, 969 were self-identified Jewish women. Cox proportional hazards models were used to estimate breast and ovarian cancer risks, as well as risk reduction from risk-reducing salpingo-oophorectomy (RRSO), by CJM and self-identified Jewish status. Results Ninety-one percent of Jewish BRCA1/2-positive women carried a CJM. Jewish women were significantly more likely to undergo RRSO than non-Jewish women (54% v 41%, respectively; odds ratio, 1.87; 95% CI, 1.44 to 2.42). Relative risks of cancer varied by CJM, with the relative risk of breast cancer being significantly lower in 6174delT mutation carriers than in non-CJM BRCA2 carriers (hazard ratio, 0.35; 95% CI, 0.18 to 0.69). No significant difference was seen in cancer risk reduction after RRSO among subgroups. Conclusion Consistent with previous results, risks for breast and ovarian cancer varied by CJM in BRCA1/2 carriers. In particular, 6174delT carriers had a lower risk of breast cancer. This finding requires additional confirmation in larger prospective and population-based cohort studies before being integrated into clinical care. PMID:22430266

  4. 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

  5. Large BRCA1 and BRCA2 genomic rearrangements in Malaysian high risk breast-ovarian cancer families.

    PubMed

    Kang, Peter; Mariapun, Shivaani; Phuah, Sze Yee; Lim, Linda Shushan; Liu, Jianjun; Yoon, Sook-Yee; Thong, Meow Keong; Mohd Taib, Nur Aishah; Yip, Cheng Har; Teo, Soo-Hwang

    2010-11-01

    Early studies of genetic predisposition due to the BRCA1 and BRCA2 genes have focused largely on sequence alterations, but it has now emerged that 4-28% of inherited mutations in the BRCA genes may be due to large genomic rearrangements of these genes. However, to date, there have been relatively few studies of large genomic rearrangements in Asian populations. We have conducted a full sequencing and large genomic rearrangement analysis (using Multiplex Ligation-dependent Probe Amplification, MLPA) of 324 breast cancer patients who were selected from a multi-ethnic hospital-based cohort on the basis of age of onset of breast cancer and/or family history. Three unrelated individuals were found to have large genomic rearrangements: 2 in BRCA1 and 1 in BRCA2, which accounts for 2/24 (8%) of the total mutations detected in BRCA1 and 1/23 (4%) of the mutations in BRCA2 detected in this cohort. Notably, the family history of the individuals with these mutations is largely unremarkable suggesting that family history alone is a poor predictor of mutation status in Asian families. In conclusion, this study in a multi-ethnic (Malay, Chinese, Indian) cohort suggests that large genomic rearrangements are present at a low frequency but should nonetheless be included in the routine testing for BRCA1 and BRCA2. PMID:20617377

  6. Large BRCA1 and BRCA2 genomic rearrangements in Malaysian high risk breast-ovarian cancer families.

    PubMed

    Kang, Peter; Mariapun, Shivaani; Phuah, Sze Yee; Lim, Linda Shushan; Liu, Jianjun; Yoon, Sook-Yee; Thong, Meow Keong; Mohd Taib, Nur Aishah; Yip, Cheng Har; Teo, Soo-Hwang

    2010-11-01

    Early studies of genetic predisposition due to the BRCA1 and BRCA2 genes have focused largely on sequence alterations, but it has now emerged that 4-28% of inherited mutations in the BRCA genes may be due to large genomic rearrangements of these genes. However, to date, there have been relatively few studies of large genomic rearrangements in Asian populations. We have conducted a full sequencing and large genomic rearrangement analysis (using Multiplex Ligation-dependent Probe Amplification, MLPA) of 324 breast cancer patients who were selected from a multi-ethnic hospital-based cohort on the basis of age of onset of breast cancer and/or family history. Three unrelated individuals were found to have large genomic rearrangements: 2 in BRCA1 and 1 in BRCA2, which accounts for 2/24 (8%) of the total mutations detected in BRCA1 and 1/23 (4%) of the mutations in BRCA2 detected in this cohort. Notably, the family history of the individuals with these mutations is largely unremarkable suggesting that family history alone is a poor predictor of mutation status in Asian families. In conclusion, this study in a multi-ethnic (Malay, Chinese, Indian) cohort suggests that large genomic rearrangements are present at a low frequency but should nonetheless be included in the routine testing for BRCA1 and BRCA2.

  7. 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

  8. 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.

  9. BRCA1 maps proximal to D17S579 on chromosome 17q21 by genetic analysis

    SciTech Connect

    Chamberlain, J.S.; Boehnke, M.; Frank, T.S.; Kiousis, S.; Junxhe Xu; Sunwei Guo; Hauser, E.R.; Helmbold, E.A.; Markel, D.S.; Keshavarzi, S.M.; Calzone, K.; Weber, B.L. ); Norum, R.A. ); Jackson, C.E. Henry Ford Hospital, Detroit, MI ); Garber, J. ); Collins, F.S. Howard Hughes Medical Inst., Ann Arbor, MI )

    1993-04-01

    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. The authors 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. 16 refs., 4 figs., 2 tabs.

  10. BRCA1 and CtIP promote alternative non-homologous end-joining at uncapped telomeres

    PubMed Central

    Badie, Sophie; Carlos, Ana Rita; Folio, Cecilia; Okamoto, Keiji; Bouwman, Peter; Jonkers, Jos; Tarsounas, Madalena

    2015-01-01

    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

  11. Rates of BRCA1/2 mutation testing among young survivors of breast cancer.

    PubMed

    Kehl, Kenneth L; Shen, Chan; Litton, Jennifer K; Arun, Banu; Giordano, Sharon H

    2016-01-01

    Guidelines in the United States recommend consideration of testing for mutations in the BRCA1 and BRCA2 genes for women diagnosed with breast cancer under age 45. Identification of mutations among survivors has implications for secondary prevention and familial risk reduction. Although only 10 % of breast cancers are diagnosed under age 45, there are approximately 2.8 million breast cancer survivors in the United States, such that the young survivor population likely numbers in the hundreds of thousands. However, little is known about genetic testing rates in this population. We assessed trends in BRCA1/2 testing among breast cancer survivors who were under age 45 at diagnosis and were treated from 2005 to 2012. Using insurance claims from a national database (MarketScan), we identified incident breast cancer cases among (1) women aged ≤40 and (2) women aged 41-45. We measured BRCA1/2 testing using Kaplan-Meier analysis and Cox proportional hazards models. Among 26,985 patients analyzed, BRCA1/2 testing rates increased with each year of diagnosis from 2005 to 2012 (P < 0.001). However, among women treated in earlier years, testing rates did not approach those of patients treated later, even after extended follow-up (median time from surgery to testing among patients treated in 2005, not reached; median time to testing among patients treated in 2012, 0.2 months for women aged ≤40 and 1.0 month for women aged 41-45). Women aged 41-45 had lower rates than women aged ≤40 throughout the analysis period (P < 0.001 for each year). BRCA1/2 testing rates among young women with incident breast cancer increased substantially in the last decade. However, most survivors treated in earlier years have never been tested. Our results demonstrate a need to better incorporate genetic counseling into survivorship and primary care for this population.

  12. 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

  13. Detection of germline BRCA1 mutations by Multiple-Dye Cleavase Fragment Length Polymorphism (MD-CFLP) method

    PubMed Central

    Casadei, S; Cortesi, L; Pensotti, V; Radice, P; Pierotti, M; Amadori, D; Calistri, D

    2001-01-01

    We describe the Multiple-Dye Cleavase Fragment Length Polymorphism (MD-CFLP) method set up for a sensitive and preliminary rapid screening of BRCA1 mutations. We analysed exons 11 and 16, which are known to cover slightly more than 70% of the whole coding region of the gene, subdivided into 4 amplicons and labelled with different fluorescent dUTPs. MD-CFLP was first utilised on a panel of 30 DNA samples in which the presence of single-base substitutions or small deletions/insertions had been previously identified by direct sequencing as gold standard, in order to define the optimal conditions in terms of PCR amplification and temperature of digestion. In a second step, we blindly analysed 21 DNA samples by MD-CFLP to verify its reliability. The sensitivity and specificity of MD-CFLP were both 100% in the first study, and 80% and 94%, respectively, in the blind sample assay. Our results demonstrate the capability of the MD-CFLP method to detect DNA sequence alterations in fragments of more than 1 kb. We conclude that CFLP is a powerful tool in mutational analysis, offering reliable results in a shorter time and at a lower cost than conventional methods, and its potential can be enhanced when internal fluorescent labelling and laser detection are used. © 2001 Cancer Research Campaignhttp://www.bjcancer.com PMID:11556835

  14. 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.

  15. Post-mortem testing; germline BRCA1/2 variant detection using archival FFPE non-tumor tissue. A new paradigm in genetic counseling

    PubMed Central

    Petersen, Annabeth Høgh; Aagaard, Mads Malik; Nielsen, Henriette Roed; Steffensen, Karina Dahl; Waldstrøm, Marianne; Bojesen, Anders

    2016-01-01

    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

  16. Gypenosides causes DNA damage and inhibits expression of DNA repair genes of human oral cancer SAS cells.

    PubMed

    Lu, Kung-Wen; Chen, Jung-Chou; Lai, Tung-Yuan; Yang, Jai-Sing; Weng, Shu-Wen; Ma, Yi-Shih; Tang, Nou-Ying; Lu, Pei-Jung; Weng, Jing-Ru; Chung, Jing-Gung

    2010-01-01

    Gypenosides (Gyp) are the major components of Gynostemma pentaphyllum Makino, a Chinese medical plant. Recently, Gyp has been shown to induce cell cycle arrest and apoptosis in many human cancer cell lines. However, there is no available information to address the effects of Gyp on DNA damage and DNA repair-associated gene expression in human oral cancer cells. Therefore, we investigated whether Gyp induced DNA damage and DNA repair gene expression in human oral cancer SAS cells. The results from flow cytometric assay indicated that Gyp-induced cytotoxic effects led to a decrease in the percentage of viable SAS cells. The results from comet assay revealed that the incubation of SAS cells with Gyp led to a longer DNA migration smear (comet tail) when compared with control and this effect was dose-dependent. The results from real-time PCR analysis indicated that treatment of SAS cells with 180 mug/ml of Gyp for 24 h led to a decrease in 14-3-3sigma, DNA-dependent serine/threonine protein kinase (DNAPK), p53, ataxia telangiectasia mutated (ATM), ataxia-telangiectasia and Rad3-related (ATR) and breast cancer gene 1 (BRCA1) mRNA expression. These observations may explain the cell death caused by Gyp in SAS cells. Taken together, Gyp induced DNA damage and inhibited DNA repair-associated gene expressions in human oral cancer SAS cells in vitro.

  17. The rate of the founder Jewish mutations in BRCA1 and BRCA2 in prostate cancer patients in Israel

    PubMed Central

    Vazina, A; Baniel, J; Yaacobi, Y; Shtriker, A; Engelstein, D; Leibovitz, I; Zehavi, M; Sidi, A A; Ramon, Y; Tischler, T; Livne, P M; Friedman, E

    2000-01-01

    Inherited predisposition occurs in 5–10% of all prostate cancer (CaP) patients, but the genes involved in conferring genetic susceptibility remain largely unknown. Several lines of evidence indicate that germline mutations in BRCA1 and BRCA2 might be associated with an increased risk for CaP. Three mutations in these two genes (185delAG and 5382InsC (BRCA1) and 6174delT (BRCA2) occur in about 2.5% of the general Ashkenazi population, and the 185delAG BRCA1 mutation, in up to 1% of non-Ashkenazi Jews. In order to assess the contribution of these germline mutations to prostate cancer in Jewish Israeli patients, we tested 174 unselected prostate cancer patients (95 of Ashkenazi origin) for these mutations by PCR amplification and modified restriction enzyme digests. Patient’s age range was 45–81 years (median 66), and in 24 (14.4%) the disease was diagnosed prior to 55 years of age. Nineteen (11%) and 12 (6.9%) patients had a first or second degree relative with CaP or breast cancer, respectively. Overall, five mutation carriers were detected: 2/152 (1.3%) 185delAG, 2/104 (2%) 5382InsC, and 1/158 (0.6%) 6174delT. In all carriers, the disease was diagnosed after the age of 55, and only one of them had a family history of breast and CaP. In addition, no allelic losses at the BRCA1 locus were demonstrated in 17 patients with a family history of CaP, using seven microsatellite markers. We conclude that the rate of the predominant Jewish BRCA1 and BRCA2 mutations in CaP patients does not significantly differ from that of the general population, and that mutational inactivation of the BRCA1 is rare in familial CaP. Thus, germline BRCA1 and BRCA2 mutations probably contribute little to CaP occurrence, to inherited predisposition, and to early onset disease in Jewish individuals. © 2000 Cancer Research Campaign PMID:10945492

  18. BRCA1: a missing link in the Fanconi anemia/BRCA pathway.

    PubMed

    D'Andrea, Alan D

    2013-04-01

    Domchek and colleagues provide a case report of a 28-year-old woman with congenital abnormalities, inherited ovarian cancer, and carboplatin hypersensitivity. Interestingly, the woman had validated germline mutations in both BRCA1 alleles. These findings further implicate BRCA1 in the Fanconi anemia/BRCA pathway and have important implications for BRCA1 genetic testing.

  19. 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.

  20. Intronic variants in BRCA1 and BRCA2 that affect RNA splicing can be reliably selected by splice-site prediction programs.

    PubMed

    Vreeswijk, Maaike P G; Kraan, Jaennelle N; van der Klift, Heleen M; Vink, Geraldine R; Cornelisse, Cees J; Wijnen, Juul T; Bakker, Egbert; van Asperen, Christi J; Devilee, Peter

    2009-01-01

    A large number of sequence variants identified in BRCA1 and BRCA2 cannot be distinguished as either disease-causing mutations or neutral variants. These so-called unclassified variants (UVs) include variants that are located in the intronic sequences of BRCA1 and BRCA2. The purpose of this study was to assess the use of splice-site prediction programs (SSPPs) to select intronic variants in BRCA1 and BRCA2 that are likely to affect RNA splicing. We performed in vitro molecular characterization of RNA of six intronic variants in BRCA1 and BRCA2. In four cases (BRCA1, c.81-6T>A and c.4986+5G>T; BRCA2, c.7617+2T>G and c.8754+5G>A) a deleterious effect on RNA splicing was seen, whereas the c.135-15_-12del variant in BRCA1 showed no effect on RNA splicing. In the case of the BRCA2 c.68-7T>A variant, RNA analysis was not sufficient to establish the clinical significance. Six SSPPs were used to predict whether an effect on RNA splicing was expected for these six variants as well as for 23 intronic variants in BRCA1 for which the effect on RNA splicing has been published. Out of a total of 174 predictions, 161 (93%) were informative (i.e., the wild-type splice-site was recognized). No false-negative predictions were observed; an effect on RNA splicing was always predicted by these programs. In four cases (2.5%) a false-positive prediction was observed. For DNA diagnostic laboratories, these programs are therefore very useful to select intronic variants that are likely to affect RNA splicing for further analysis.

  1. Cancer risks in first degree relatives of BRCA1 mutation carriers: effects of mutation and proband disease status

    PubMed Central

    Gronwald, J; Huzarski, T; Byrski, B; Medrek, K; Menkiszak, J; Monteiro, A N; Sun, P; Lubinski, J; Narod, S A

    2006-01-01

    Background Mutations in the BRCA1 (MIM 113705) gene are found in many families with multiple cases of breast and ovarian cancer, and women with a BRCA1 mutation are at significantly higher risk of developing breast and ovarian cancer than are the general public. Methods We obtained blood samples and pedigree information from 3568 unselected cases of early‐onset breast cancer and 609 unselected patients with ovarian cancer from hospitals throughout Poland. Genetic testing was performed for three founder BRCA1 mutations. We also calculated the risk of breast and ovarian cancer to age 75 in the first degree relatives of carriers using Kaplan‐Meier methods. Results The three founder BRCA1 mutations were identified in 273 samples (187 with 5382insC, 22 with 4153delA, and 64 with C61G). A mutation was present in 4.3% of patients with breast cancer and 12.3% of patients with ovarian cancer. The overall risk of breast cancer to age 75 in relatives was 33% and the risk of ovarian cancer was 15%. The risk for breast cancer was 42% higher among first degree relatives of carriers of the C61G missense mutation compared to other mutations (HR = 1.42; p = 0.10) and the risk for ovarian cancer was lower than average (OR = 0.26; p = 0.03). Relatives of women diagnosed with breast cancer had a higher risk of breast cancer than relatives of women diagnosed with ovarian cancer (OR = 1.7; p = 0.03). Conclusions The risk of breast cancer in female relatives of women with a BRCA1 mutation depends on whether the proband was diagnosed with breast or ovarian cancer. PMID:16227521

  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. 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.

  4. 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

  5. Recurrent mutation testing of BRCA1 and BRCA2 in Asian breast cancer patients identify carriers in those with presumed low risk by family history.

    PubMed

    Kang, Peter Choon Eng; Phuah, Sze Yee; Sivanandan, Kavitta; Kang, In Nee; Thirthagiri, Eswary; Liu, Jian Jun; Hassan, Norhashimah; Yoon, Sook-Yee; Thong, Meow Keong; Hui, Miao; Hartman, Mikael; Yip, Cheng Har; Mohd Taib, Nur Aishah; Teo, Soo Hwang

    2014-04-01

    Although the breast cancer predisposition genes BRCA1 and BRCA2 were discovered more than 20 years ago, there remains a gap in the availability of genetic counselling and genetic testing in Asian countries because of cost, access and inaccurate reporting of family history of cancer. In order to improve access to testing, we developed a rapid test for recurrent mutations in our Asian populations. In this study, we designed a genotyping assay with 55 BRCA1 and 44 BRCA2 mutations previously identified in Asian studies, and validated this assay in 267 individuals who had previously been tested by full sequencing. We tested the prevalence of these mutations in additional breast cancer cases. Using this genotyping approach, we analysed recurrent mutations in 533 Malaysian breast cancer cases with <10 % a priori risk, and found 1 BRCA1 (0.2 %) and 5 BRCA2 (0.9 %) carriers. Testing in a hospital-based unselected cohort of 532 Singaporean breast cancer cases revealed 6 BRCA1 (1.1 %) and 3 BRCA2 (0.6 %) carriers. Overall, 2 recurrent BRCA1 and 1 BRCA2 mutations in Malays, 3 BRCA1 and 2 BRCA2 mutations in Chinese and 1 BRCA1 mutation in Indians account for 60, 24 and 20 % of carrier families, respectively. By contrast, haplotype analyses suggest that a recurrent BRCA2 mutation (c.262_263delCT) found in 5 unrelated Malay families has at least 3 distinct haplotypes. Taken together, our data suggests that panel testing may help to identify carriers, particularly Asian BRCA2 carriers, who do not present with a priori strong family history characteristics.

  6. 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

  7. ‘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

  8. Recurrent mutation testing of BRCA1 and BRCA2 in Asian breast cancer patients identify carriers in those with presumed low risk by family history.

    PubMed

    Kang, Peter Choon Eng; Phuah, Sze Yee; Sivanandan, Kavitta; Kang, In Nee; Thirthagiri, Eswary; Liu, Jian Jun; Hassan, Norhashimah; Yoon, Sook-Yee; Thong, Meow Keong; Hui, Miao; Hartman, Mikael; Yip, Cheng Har; Mohd Taib, Nur Aishah; Teo, Soo Hwang

    2014-04-01

    Although the breast cancer predisposition genes BRCA1 and BRCA2 were discovered more than 20 years ago, there remains a gap in the availability of genetic counselling and genetic testing in Asian countries because of cost, access and inaccurate reporting of family history of cancer. In order to improve access to testing, we developed a rapid test for recurrent mutations in our Asian populations. In this study, we designed a genotyping assay with 55 BRCA1 and 44 BRCA2 mutations previously identified in Asian studies, and validated this assay in 267 individuals who had previously been tested by full sequencing. We tested the prevalence of these mutations in additional breast cancer cases. Using this genotyping approach, we analysed recurrent mutations in 533 Malaysian breast cancer cases with <10 % a priori risk, and found 1 BRCA1 (0.2 %) and 5 BRCA2 (0.9 %) carriers. Testing in a hospital-based unselected cohort of 532 Singaporean breast cancer cases revealed 6 BRCA1 (1.1 %) and 3 BRCA2 (0.6 %) carriers. Overall, 2 recurrent BRCA1 and 1 BRCA2 mutations in Malays, 3 BRCA1 and 2 BRCA2 mutations in Chinese and 1 BRCA1 mutation in Indians account for 60, 24 and 20 % of carrier families, respectively. By contrast, haplotype analyses suggest that a recurrent BRCA2 mutation (c.262_263delCT) found in 5 unrelated Malay families has at least 3 distinct haplotypes. Taken together, our data suggests that panel testing may help to identify carriers, particularly Asian BRCA2 carriers, who do not present with a priori strong family history characteristics. PMID:24578176

  9. Interpreting epidemiological research: blinded comparison of methods used to estimate the prevalence of inherited mutations in BRCA1

    PubMed Central

    Eng, C.; Brody, L.; Wagner, T.; Devilee, P.; Vijg, J.; Szabo, C.; Tavtigian, S.; Nathanson, K.; Ostrander, E.; Frank, T.

    2001-01-01

    While sequence analysis is considered by many to be the most sensitive method of detecting unknown mutations in large genes such as BRCA1, most published estimates of the prevalence of mutations in this gene have been derived from studies that have used other methods of gene analysis. In order to determine the relative sensitivity of techniques that are widely used in research on BRCA1, a set of blinded samples containing 58 distinct mutations were analysed by four separate laboratories. Each used one of the following methods: single strand conformational polymorphism analysis (SSCP), conformation sensitive gel electrophoresis (CSGE), two dimensional gene scanning (TDGS), and denaturing high performance liquid chromatography (DHPLC). Only the laboratory using DHPLC correctly identified each of the mutations. The laboratory using TDGS correctly identified 91% of the mutations but produced three apparent false positive results. The laboratories using SSCP and CSGE detected abnormal migration for 72% and 76% of the mutations, respectively, but subsequently confirmed and reported only 65% and 60% of mutations, respectively. False negatives therefore resulted not only from failure of the techniques to distinguish wild type from mutant, but also from failure to confirm the mutation by sequence analysis as well as from human errors leading to misreporting of results. These findings characterise sources of error in commonly used methods of mutation detection that should be addressed by laboratories using these methods. Based upon sources of error identified in this comparison, it is likely that mutations in BRCA1 and BRCA2 are more prevalent than some studies have previously reported. The findings of this comparison provide a basis for interpreting studies of mutations in susceptibility genes across many inherited cancer syndromes.


Keywords: BRCA1; mutation detection; cancer genetics PMID:11748305

  10. A Survey of BRCA1, BRCA2, and PALB2 mutations in women with breast cancer in Trinidad and Tobago.

    PubMed

    Donenberg, Talia; Ahmed, Humayun; Royer, Robert; Zhang, Shiyu; Narod, Steven A; George, Sophia; Akbari, Mohammad R; Ali, Jameel; Hurley, Judith

    2016-08-01

    The mortality rate from breast cancer in the nation of Trinidad and Tobago is among the highest of any country in the Caribbean region. The contribution of inherited gene mutations to the burden of breast cancer in Trinidad and Tobago has not been studied. We examined the prevalence of mutations in three susceptibility genes (BRCA1, BRCA2, and PALB2) in breast cancer patients in Trinidad and Tobago. We studied 268 unselected breast cancer patients from Trinidad and Tobago and looked for mutations across the entire coding sequences of BRCA1, BRCA2, and PALB2. Overall, 28 of 268 patients (10.4 %) had a mutation in one of the three genes, including 15 in BRCA1, ten in BRCA2, two in PALB2, and one in both BRCA2 and PALB2. There were 25 different mutations identified; of these, four mutations were seen in two patients each. Given the high prevalence of mutations, it is reasonable to offer genetic testing for these three genes to all breast cancer patients in Trinidad and Tobago. PMID:27469594

  11. MicroRNA-based molecular classification of non-BRCA1/2 hereditary breast tumours

    PubMed Central

    Tanic, M; Andrés, E; M Rodriguez-Pinilla, S; Marquez-Rodas, I; Cebollero-Presmanes, M; Fernandez, V; Osorio, A; Benítez, J; Martinez-Delgado, B

    2013-01-01

    Background: Hereditary breast cancer comprises 5–10% of all breast cancers. Mutations in two high-risk susceptibility genes, BRCA1 and BRCA2, along with rare intermediate-risk genes and common low-penetrance alleles identified, altogether explain no more than 45% of the high-risk breast cancer families, although the majority of cases are unaccounted for and are designated as BRCAX tumours. Micro RNAs have called great attention for classification of different cancer types and have been implicated in a range of important biological processes and are deregulated in cancer pathogenesis. Methods: Here we have performed an exploratory hypothesis-generating study of miRNA expression profiles in a large series of 66 primary hereditary breast tumours by microarray analysis. Results: Unsupervised clustering analysis of miRNA molecular profiles revealed distinct subgroups of BRCAX tumours, ‘normal-like' BRCAX-A, ‘proliferative' BRCAX-B, ‘BRCA1/2-like' BRCAX-C and ‘undefined' BRCAX-D subgroup. These findings introduce a new insight in the biology of hereditary breast cancer, defining specific BRCAX subgroups, which could help in the search for novel susceptibility pathways in hereditary breast cancer. Conclusion: Our data demonstrate that BRCAX hereditary breast tumours can be sub-classified into four previously unknown homogenous groups characterised by specific miRNA expression signatures and histopathological features. PMID:24104964

  12. 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

  13. 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.

  14. 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.

  15. Carboplatin and taxol resistance develops more rapidly in functional BRCA1 compared to dysfunctional BRCA1 ovarian cancer cells.

    PubMed

    Busschots, Steven; O'Toole, Sharon; O'Leary, John J; Stordal, Britta

    2015-08-01

    A major risk factor for ovarian cancer is germline mutations of BRCA1/2. It has been found that (80%) of cellular models with acquired platinum or taxane resistance display an inverse resistance relationship, that is collateral sensitivity to the other agent. We used a clinically relevant comparative selection strategy to develop novel chemoresistant cell lines which aim to investigate the mechanisms of resistance that arise from different exposures of carboplatin and taxol on cells having BRCA1 function (UPN251) or dysfunction (OVCAR8). Resistance to carboplatin and taxol developed quicker and more stably in UPN251 (BRCA1-wildtype) compared to OVCAR8 (BRCA1-methylated). Alternating carboplatin and taxol treatment delayed but did not prevent resistance development when compared to single-agent administration. Interestingly, the sequence of drug exposure influenced the resistance mechanism produced. UPN251-6CALT (carboplatin first) and UPN251-6TALT (taxol first) have different profiles of cross resistance. UPN251-6CALT displays significant resistance to CuSO4 (2.3-fold, p=0.004) while UPN251-6TALT shows significant sensitivity to oxaliplatin (0.6-fold, p=0.01). P-glycoprotein is the main mechanism of taxol resistance found in the UPN251 taxane-resistant sublines. UPN251 cells increase cellular glutathione levels (3.0-fold, p=0.02) in response to carboplatin treatment. However, increased glutathione is not maintained in the carboplatin-resistant sublines. UPN251-7C and UPN251-6CALT are low-level resistant to CuSO4 suggesting alterations in copper metabolism. However, none of the UPN251 sublines have alterations in the protein expression of ATP7A or CTR1. The protein expression of BRCA1 and MRP2 is unchanged in the UPN251 sublines. The UPN251 sublines remain sensitive to parp inhibitors veliparib and CEP8983 suggesting that these agents are candidates for the treatment of platinum/taxane resistant ovarian cancer patients.

  16. The negative interplay between Aurora A/B and BRCA1/2 controls cancer cell growth and tumorigenesis via distinct regulation of cell cycle progression, cytokinesis, and tetraploidy

    PubMed Central

    2014-01-01

    It is well known that the activation of Aurora A/B (Aur A/B) or inactivation of BRCA1/2 induces tumor formation. Others and we have reported that the mutual suppression between Aur A/B and BRCA1/2 may manipulate cancer cell growth and tumorigenesis, however, the interactive regulation and mechanism between these molecules are still elusive. In this study, by consecutive silencing of Aur A/B or/and BRCA1/2 with specific shRNAs, we showed that, in BRCA2-deficient pancreatic cancer cell line Capan-1 and in ovarian cancer cell line OVCA433, Aur A/B and BRCA1/2 inversely regulated the expression of each other likely through proteasome-mediated proteolysis but not through gene transcription. Aur A/B and BRCA1/2 conversely regulated cell cycle progression mainly through control of p53 and cyclin A. Moreover, the disruption of Aur A/B blocked abnormal cytokinesis and decreased cell multinuclearity and chromosome tetraploidy, whereas the deprivation of BRCA1/2 promoted the abnormal cytokinesis and enhanced the cell multinuclearity and tetraploidy. Furthermore, we showed by animal assays that the depletion of Aur A/B inhibited tumor growth of both cell lines, while the knockdown of BRCA1/2 promoted the tumor growth. However, the concurrent silencing of Aur A/B and BRCA1/2 diminished the effects of these molecules on the regulation of cell cycle, cytokinesis, and tetraploidy, leading to the burdened tumor sizes similar to those induced by scrambled shRNA-treated control cells. In summary, our study revealed that the negative interplay between Aur A/B and BRCA1/2 inversely controls the cell proliferation, cell cycle progression, cell multinuclearity, and tetraploidization to modulate tumorigenesis. PMID:24775809

  17. 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

  18. 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

  19. 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.

  20. 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

  1. Embryonic mammary signature subsets are activated in Brca1-/- and basal-like breast cancers

    PubMed Central

    2013-01-01

    Introduction Cancer is often suggested to result from development gone awry. Links between normal embryonic development and cancer biology have been postulated, but no defined genetic basis has been established. We recently published the first transcriptomic analysis of embryonic mammary cell populations. Embryonic mammary epithelial cells are an immature progenitor cell population, lacking differentiation markers, which is reflected in their very distinct genetic profiles when compared with those of their postnatal descendents. Methods We defined an embryonic mammary epithelial signature that incorporates the most highly expressed genes from embryonic mammary epithelium when compared with the postnatal mammary epithelial cells. We looked for activation of the embryonic mammary epithelial signature in mouse mammary tumors that formed in mice in which Brca1 had been conditionally deleted from the mammary epithelium and in human breast cancers to determine whether any genetic links exist between embryonic mammary cells and breast cancers. Results Small subsets of the embryonic mammary epithelial signature were consistently activated in mouse Brca1-/- tumors and human basal-like breast cancers, which encoded predominantly transcriptional regulators, cell-cycle, and actin cytoskeleton components. Other embryonic gene subsets were found activated in non-basal-like tumor subtypes and repressed in basal-like tumors, including regulators of neuronal differentiation, transcription, and cell biosynthesis. Several embryonic genes showed significant upregulation in estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, and/or grade 3 breast cancers. Among them, the transcription factor, SOX11, a progenitor cell and lineage regulator of nonmammary cell types, is found highly expressed in some Brca1-/- mammary tumors. By using RNA interference to silence SOX11 expression in breast cancer cells, we found evidence that SOX11 regulates breast cancer cell

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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.

  7. After BRCA1 and BRCA2-what next? Multifactorial segregation analyses of three-generation, population-based Australian families affected by female breast cancer.

    PubMed

    Cui, J; Antoniou, A C; Dite, G S; Southey, M C; Venter, D J; Easton, D F; Giles, G G; McCredie, M R; Hopper, J L

    2001-02-01

    Mutations in BRCA1 and BRCA2 that cause a dominantly inherited high risk of female breast cancer seem to explain only a small proportion of the aggregation of the disease. To study the possible additional genetic components, we conducted single-locus and two-locus segregation analyses, with and without a polygenic background, using three-generation families ascertained through 858 women with breast cancer diagnosed at age <40 years, ascertained through population cancer registries in Melbourne and Sydney, Australia. Extensive testing for deleterious mutations in BRCA1 and BRCA2, to date, has identified 34 carriers. Our analysis suggested that, after other possible unmeasured familial factors are adjusted for and the known BRCA1 and BRCA2 mutation carriers are excluded, there appears to be a residual dominantly inherited risk of female breast cancer in addition to that derived from mutations in BRCA1 and BRCA2. This study also suggests that there is a substantial recessively inherited risk of early-onset breast cancer. According to the best-fitting model, after excluding known carriers of mutations in BRCA1 and BRCA2, about 1/250 (95% confidence interval [CI] 1/500 to 1/125) women have a recessive risk of 86% (95% CI 69%-100%) by age 50 years and of almost 100% by age 60 years. Possible reasons that our study has implicated a novel strong recessive effect include our inclusion of data on lineal aunts and grandmothers, study of families ascertained through women with early-onset breast cancer, allowance for multiple familial factors in the analysis, and removal of families for whom the cause (i.e., BRCA1 or BRCA2) is known. Our findings may have implications for attempts to identify new breast cancer-susceptibility genes. PMID:11133358

  8. On the origin and diffusion of BRCA1 c.5266dupC (5382insC) in European populations

    PubMed Central

    Hamel, Nancy; Feng, Bing-Jian; Foretova, Lenka; Stoppa-Lyonnet, Dominique; Narod, Steven A; Imyanitov, Evgeny; Sinilnikova, Olga; Tihomirova, Laima; Lubinski, Jan; Gronwald, Jacek; Gorski, Bohdan; Hansen, Thomas v O; Nielsen, Finn C; Thomassen, Mads; Yannoukakos, Drakoulis; Konstantopoulou, Irene; Zajac, Vladimir; Ciernikova, Sona; Couch, Fergus J; Greenwood, Celia M T; Goldgar, David E; Foulkes, William D

    2011-01-01

    The BRCA1 mutation c.5266dupC was originally described as a founder mutation in the Ashkenazi Jewish (AJ) population. However, this mutation is also present at appreciable frequency in several European countries, which raises intriguing questions about the origins of the mutation. We genotyped 245 carrier families from 14 different population groups (Russian, Latvian, Ukrainian, Czech, Slovak, Polish, Danish, Dutch, French, German, Italian, Greek, Brazilian and AJ) for seven microsatellite markers and confirmed that all mutation carriers share a common haplotype from a single founder individual. Using a maximum likelihood method that allows for both recombination and mutational events of marker loci, we estimated that the mutation arose some 1800 years ago in either Scandinavia or what is now northern Russia and subsequently spread to the various populations we genotyped during the following centuries, including the AJ population. Age estimates and the molecular evolution profile of the most common linked haplotype in the carrier populations studied further suggest that c.5266dupC likely entered the AJ gene pool in Poland approximately 400–500 years ago. Our results illustrate that (1) BRCA1 c.5266dupC originated from a single common ancestor and was a common European mutation long before becoming an AJ founder mutation and (2) the mutation is likely present in many additional European countries where genetic screening of BRCA1 may not yet be common practice. PMID:21119707

  9. The breast cancer susceptibility genes (BRCA) in breast and ovarian cancers

    PubMed Central

    Paul, Arindam; Paul, Soumen

    2015-01-01

    The Breast Cancer Susceptibility Genes, BRCA1 and BRCA2, are the dynamic regulators of genomic integrity. Inherited mutations in these genes are associated with the development of cancer in multiple organs including the breast and ovary. Mutations of BRCA1/2 genes greatly increase lifetime risk to develop breast and ovarian cancer and these mutations are frequently observed in hereditary breast and ovarian cancers. In addition, misregulation and altered expressions of BRCA1/2 proteins potentiate sporadic forms of breast cancer. In particular, both genes contribute to DNA repair and transcriptional regulation in response to DNA damage. Thus, deficiencies of BRCA1/2 functions lead to the accumulation of genetic alterations and ultimately influence the development of cancer. Studies since identification of both BRCA1 and BRCA2 have provided strong evidences for their tumor suppressor activities specifically for breast and ovarian cancer and this article aims to review the current state of knowledge regarding the BRCAs and associated cancer risk. PMID:24389207

  10. 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 ...

  11. 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

  12. 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

  13. Common alleles at 6q25.1 and 1p11.2 are associated with breast cancer risk for BRCA1 and BRCA2 mutation carriers.

    PubMed

    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; Putignano, Anna Laura; 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; Evans, D Gareth; Lalloo, Fiona; Eeles, Ros; Izatt, Louise; Adlard, Julian; Davidson, Rosemarie; Eccles, Diana; Ong, Kai-ren; Cook, Jackie; Douglas, Fiona; Paterson, Joan; Kennedy, M John; 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; Dressler, Anne Catharina; Hansen, Thomas v O; Jønson, Lars; Ejlertsen, Bent; Barkardottir, Rosa Bjork; Kirchhoff, Tomas; Offit, Kenneth; Piedmonte, Marion; Rodriguez, Gustavo; Small, Laurie; Boggess, John; Blank, Stephanie; Basil, Jack; Azodi, Masoud; Toland, Amanda Ewart; 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

    2011-08-15

    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 (r(2) = 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.

  14. Structure of a BRCA1/BARD1 Complex: a Heterodimeric RING-RING Interaction

    SciTech Connect

    Brzovic, Peter S.; Rajagopal, Ponni; Hoyt, David W.; King, Mary-Claire; Klevit, Rachel E.

    2001-10-01

    The N-terminal RING domain of the breast and ovarian cancer tumor suppressor BRCA1 interacts with multiple cognate proteins, including the RING protein, BARD1. Proper function of the BRCA1 RING domain is critical, as evidenced by the many cancer-predisposing mutations found within this domain. We present the solution structure of the N-terminal RING domain heterodimer of BRCA1 and BARD1. Comparison with the RAG1 RING homodimer reveals the structural diversity of complexes formed by interactions between different RING domains. The BRCA1/BARD1 structure provides a model for its ubiquitin ligase activity, illustrates how the BRCA1 RING domain can be involved in associations with multiple protein partners, and provdes a framework for understanding cancer-causing mutations at the molecular level.

  15. Panobinostat Enhances Cytarabine and Daunorubicin Sensitivities in AML Cells through Suppressing the Expression of BRCA1, CHK1, and Rad51

    PubMed Central

    Edwards, Holly; Caldwell, J. Timothy; Chen, Wei; Inaba, Hiroto; Xu, Xuelian; Buck, Steven A.; Taub, Jeffrey W.; Baker, Sharyn D.; Ge, Yubin

    2013-01-01

    Acute myeloid leukemia (AML) remains a challenging disease to treat and urgently requires new therapies to improve its treatment outcome. In this study, we investigated the molecular mechanisms underlying the cooperative antileukemic activities of panobinostat and cytarabine or daunorubicin (DNR) in AML cell lines and diagnostic blast samples in vitro and in vivo. Panobinostat suppressed expression of BRCA1, CHK1, and RAD51 in AML cells in a dose-dependent manner. Further, panobinostat significantly increased cytarabine- or DNR-induced DNA double-strand breaks and apoptosis, and abrogated S and/or G2/M cell cycle checkpoints. Analogous results were obtained by shRNA knockdown of BRCA1, CHK1, or RAD51. Cotreatment of NOD-SCID-IL2Rγnull mice bearing AML xenografts with panobinostat and cytarabine significantly increased survival compared to either cytarabine or panobinostat treatment alone. Additional studies revealed that panobinostat suppressed the expression of BRCA1, CHK1, and RAD51 through downregulation of E2F1 transcription factor. Our results establish a novel mechanism underlying the cooperative antileukemic activities of these drug combinations in which panobinostat suppresses expression of BRCA1, CHK1, and RAD51 to enhance cytarabine and daunorubicin sensitivities in AML cells. PMID:24244429

  16. 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

  17. 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

  18. MicroRNA expression signatures for the prediction of BRCA1/2 mutation-associated hereditary breast cancer in paraffin-embedded formalin-fixed breast tumors.

    PubMed

    Tanic, Miljana; Yanowski, Kira; Gómez-López, Gonzalo; Rodriguez-Pinilla, María Socorro; Marquez-Rodas, Iván; Osorio, Ana; Pisano, David G; Martinez-Delgado, Beatriz; Benítez, Javier

    2015-02-01

    Screening for germline mutations in breast cancer-associated genes BRCA1 and BRCA2 is indicated for patients with breast cancer from high-risk breast cancer families and influences both treatment options and clinical management. However, only 25% of selected patients test positive for BRCA1/2 mutation, indicating that additional diagnostic biomarkers are necessary. We analyzed 124 formalin-fixed paraffin-embedded (FFPE) tumor samples from patients with hereditary (104) and sporadic (20) invasive breast cancer, divided into two series (A and B). Microarray expression profiling of 829 human miRNAs was performed on 76 samples (Series A), and bioinformatics tool Prophet was used to develop and test a microarray classifier. Samples were stratified into a training set (n = 38) for microarray classifier generation and a test set (n = 38) for signature validation. A 35-miRNA microarray classifier was generated for the prediction of BRCA1/2 mutation status with a reported 95% (95% CI = 0.88-1.0) and 92% (95% CI: 0.84-1.0) accuracy in the training and the test set, respectively. Differential expression of 12 miRNAs between BRCA1/2 mutation carriers versus noncarriers was validated by qPCR in an independent tumor series B (n = 48). Logistic regression model based on the expression of six miRNAs (miR-142-3p, miR-505*, miR-1248, miR-181a-2*, miR-25* and miR-340*) discriminated between tumors from BRCA1/2 mutation carriers and noncarriers with 92% (95% CI: 0.84-0.99) accuracy. In conclusion, we identified miRNA expression signatures predictive of BRCA1/2 mutation status in routinely available FFPE breast tumor samples, which may be useful to complement current patient selection criteria for gene testing by identifying individuals with high likelihood of being BRCA1/2 mutation carriers.

  19. High-density genetic map of the BRCA1 region of chromosome 17q12-q21

    SciTech Connect

    Anderson, L.A.; Friedman, L.; Lynch, E.; King, M.C. ); Osborne-Lawrence, S.; Bowcock, A. ); Weissenbach, J. )

    1993-09-01

    To facilitate the positional cloning of the breast-ovarian cancer gene BRCA1, the authors constructed a high-density genetic map of the 8.3-cM interval between D17S250 and GIP on chromosome 17q12-q21. Markers were mapped by linkage in the CEPH and in extended kindreds in the breast cancer series. The map comprises 33 ordered polymorphisms, including 12 genes and 21 anonymous markers, yielding an average of one polymorphism every 250 kb. Twenty-five of the markers are PCR-based systems. The order of polymorphic genes and markers is cen-D17S250-D17S518-HER2-THRA1-RARA-D17S80-KRT10-[D17S800-D17S857]-GAS-D17S856-EDH17B-D17S855-D17S859-D17S858-[PPY-D17S78]-D17S183-EPB3-D17S579-D17S509-[D17S508-D17S190 = D17S810]-D17S791-[D17S181 = D17S806]-D17S797-HOX2B-GP3A-[D17S507 = GIP]-qter. BRCA1 lies in the middle of the interval, between THRA1 and D17S183. Markers from this map can be used to determine whether cancer is linked to BRCA1 in families, to evaluate whether tumors have lost heterozygosity at loci in the region, and to identify probes for characterizing chromosomal rearrangements from patients and from tumors. 21 refs., 1 fig., 3 tabs.

  20. BRCA1 and BRCA2 mutations and the risk for colorectal cancer.

    PubMed

    Sopik, V; Phelan, C; Cybulski, C; Narod, S A

    2015-05-01

    Women who carry a BRCA1 or BRCA2 mutation are at high risk of breast and ovarian cancer, and may be at moderately increased risk of other cancer types. This review examines studies to date that have evaluated the risk of BRCA1 and BRCA2 mutations for colorectal cancer. Accurate knowledge of colorectal cancer risk in BRCA1/2 carriers is important, because colonoscopy screening can prevent colorectal cancer through the removal of adenomatous polyps. Most studies that have identified an increased risk for colorectal cancer in BRCA1/2 mutation carriers were in high-risk cancer families, while studies that found no association were conducted in specific populations and involved the analysis of founder mutations. A recent prospective study of 7015 women with a BRCA1 or BRCA2 mutation identified significant fivefold increased risk of colorectal cancer among BRCA1 mutation carriers younger than 50 years [standardized incidence ratio (SIR): 4.8; 95% CI: 2.2-9], but not in women with a BRCA2 mutation or in older women. Based on this evidence, women with BRCA1 mutations should be counseled about their increased risk for early-onset colorectal cancer, and offered colonoscopy at 3- to 5-year intervals between the ages of 40 and 50 years, and should follow population guidelines thereafter.

  1. 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

  2. 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 Central

    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

  3. Prevalence and penetrance of germline BRCA1 and BRCA2 mutations in a population series of 649 women with ovarian cancer.

    PubMed

    Risch, H A; McLaughlin, J R; Cole, D E; Rosen, B; Bradley, L; Kwan, E; Jack, E; Vesprini, D J; Kuperstein, G; Abrahamson, J L; Fan, I; Wong, B; Narod, S A

    2001-03-01

    A population-based series of 649 unselected incident cases of ovarian cancer diagnosed in Ontario, Canada, during 1995-96 was screened for germline mutations in BRCA1 and BRCA2. We specifically tested for 11 of the most commonly reported mutations in the two genes. Then, cases were assessed with the protein-truncation test (PTT) for exon 11 of BRCA1, with denaturing gradient gel electrophoresis for the remainder of BRCA1, and with PTT for exons 10 and 11 of BRCA2. No mutations were found in all 134 women with tumors of borderline histology. Among the 515 women with invasive cancers, we identified 60 mutations, 39 in BRCA1 and 21 in BRCA2. The total mutation frequency among women with invasive cancers, 11.7% (95% confidence interval [95%CI] 9.2%-14.8%), is higher than previous estimates. Hereditary ovarian cancers diagnosed at age <50 years were mostly (83%) due to BRCA1, whereas the majority (60%) of those diagnosed at age >60 years were due to BRCA2. Mutations were found in 19% of women reporting first-degree relatives with breast or ovarian cancer and in 6.5% of women with no affected first-degree relatives. Risks of ovarian, breast, and stomach cancers and leukemias/lymphomas were increased nine-, five-, six- and threefold, respectively, among first-degree relatives of cases carrying BRCA1 mutations, compared with relatives of noncarriers, and risk of colorectal cancer was increased threefold for relatives of cases carrying BRCA2 mutations. For carriers of BRCA1 mutations, the estimated penetrance by age 80 years was 36% for ovarian cancer and 68% for breast cancer. In breast-cancer risk for first-degree relatives, there was a strong trend according to mutation location along the coding sequence of BRCA1, with little evidence of increased risk for mutations in the 5' fifth, but 8.8-fold increased risk for mutations in the 3' fifth (95%CI 3.6-22.0), corresponding to a carrier penetrance of essentially 100%. Ovarian, colorectal, stomach, pancreatic, and prostate

  4. Characterization of 10 new polymorphic dinucleotide repeats and generation of a high-density microsatellite-based physical map of the BRCA1 region of chromosome 17q21

    SciTech Connect

    Couch, F.J.; Xu, J.; Weber, B.L.

    1994-12-01

    A familial early onset breast cancer gene (BRCA1) has been localized to chromosome 17q21. To aid in the identification of this gene a number of new microsatellite markers from the D17S857 to D17S78 region were isolated and characterized. These markers, along with previously published markers from the region, were localized on a physical map by STS content mapping of cosmids from the BRCA1 interval. This high-density STS map of the BRCA1 region will be useful for linkage studies of families with apparent inherited breast cancer and for loss of heterozygosity analysis of breast tumor DNAs. 19 refs., 2 figs., 2 tabs.

  5. Deleterious BRCA1/2 mutations in an urban population of Black women.

    PubMed

    Lynce, Filipa; Smith, Karen Lisa; Stein, Julie; DeMarco, Tiffani; Wang, Yiru; Wang, Hongkun; Fries, Melissa; Peshkin, Beth N; Isaacs, Claudine

    2015-08-01

    Information on the prevalence of deleterious BRCA1 and BRCA2 (BRCA1/2) mutations in clinic-based populations of Black women is limited. In order to address this gap, we performed a retrospective study to determine the prevalence of deleterious BRCA1/2 mutations, predictors of having a mutation, and acceptance of risk-reducing surgeries in Black women. In an urban unselected clinic-based population, we evaluated 211 self-identified Black women who underwent genetic counseling for hereditary breast-ovarian cancer syndrome. BRCA1/2 mutations were identified in 13.4% of the participants who received genetic testing. Younger age at diagnosis, higher BRCAPRO score, significant family history, and diagnosis of triple-negative breast cancer were associated with identification of a BRCA1/2 mutation. Of the affected patients found to have a deleterious mutation, almost half underwent prophylactic measures. In our study population, 1 in 7 Black women who underwent genetic testing harbored a deleterious BRCA1/2 mutation independent of age at diagnosis or family history.

  6. Ovarian Cancer and BRCA1/2 Testing: Opportunities to Improve Clinical Care and Disease Prevention

    PubMed Central

    Karakasis, Katherine; Burnier, Julia V.; Bowering, Valerie; Oza, Amit M.; Lheureux, Stephanie

    2016-01-01

    Without prevention or screening options available, ovarian cancer is the most lethal malignancy of the female reproductive tract. High-grade serous ovarian cancer (HGSOC) is the most common histologic subtype, and the role of germline BRCA1/2 mutation in predisposition and prognosis is established. Given the targeted treatment opportunities with PARP inhibitors, a predictive role for BRCA1/2 mutation has emerged. Despite recommendations to provide BRCA1/2 testing to all women with histologically confirmed HGSOC, uniform implementation remains challenging. The opportunity to review and revise genetic screening and testing practices will identify opportunities, where universal adoption of BRCA1/2 mutation testing will impact and improve treatment of women with ovarian cancer. Improving education and awareness of genetic testing for women with cancer, as well as the broader general community, will help focus much-needed attention on opportunities to advance prevention and screening programs in ovarian cancer. This is imperative not only for women with cancer and those at risk of developing cancer but also for their first-degree relatives. In addition, BRCA1/2 testing may have direct implications for patients with other types of cancers, many of which are now being found to have BRCA1/2 involvement. PMID:27242959

  7. Population Testing for Cancer Predisposing BRCA1/BRCA2 Mutations in the Ashkenazi-Jewish Community: A Randomized Controlled Trial

    PubMed Central

    Manchanda, Ranjit; Loggenberg, Kelly; Sanderson, Saskia; Burnell, Matthew; Wardle, Jane; Gessler, Sue; Side, Lucy; Balogun, Nyala; Desai, Rakshit; Kumar, Ajith; Dorkins, Huw; Wallis, Yvonne; Chapman, Cyril; Taylor, Rohan; Jacobs, Chris; Tomlinson, Ian; McGuire, Alistair; Beller, Uziel; Menon, Usha

    2015-01-01

    Background: Technological advances raise the possibility of systematic population-based genetic testing for cancer-predisposing mutations, but it is uncertain whether benefits outweigh disadvantages. We directly compared the psychological/quality-of-life consequences of such an approach to family history (FH)–based testing. Methods: In a randomized controlled trial of BRCA1/2 gene-mutation testing in the Ashkenazi Jewish (AJ) population, we compared testing all participants in the population screening (PS) arm with testing those fulfilling standard FH-based clinical criteria (FH arm). Following a targeted community campaign, AJ participants older than 18 years were recruited by self-referral after pretest genetic counseling. The effects of BRCA1/2 genetic testing on acceptability, psychological impact, and quality-of-life measures were assessed by random effects regression analysis. All statistical tests were two-sided. Results: One thousand, one hundred sixty-eight AJ individuals were counseled, 1042 consented, 1034 were randomly assigned (691 women, 343 men), and 1017 were eligible for analysis. Mean age was 54.3 (SD = 14.66) years. Thirteen BRCA1/2 carriers were identified in the PS arm, nine in the FH arm. Five more carriers were detected among FH-negative FH-arm participants following study completion. There were no statistically significant differences between the FH and PS arms at seven days or three months on measures of anxiety, depression, health anxiety, distress, uncertainty, and quality-of-life. Contrast tests indicated that overall anxiety (P = .0001) and uncertainty (P = .005) associated with genetic testing decreased; positive experience scores increased (P = .0001); quality-of-life and health anxiety did not change with time. Overall, 56% of carriers did not fulfill clinical criteria for genetic testing, and the BRCA1/2 prevalence was 2.45%. Conclusion: Compared with FH-based testing, population-based genetic testing in Ashkenazi Jews doesn

  8. Targeting Aberrant DNA double strand break repair in triple negative breast cancer with alpha particle emitter radiolabeled anti-EGFR antibody

    PubMed Central

    Song, Hong; Hedayati, Mohammad; Hobbs, Robert F.; Shao, Chunbo; Bruchertseifer, Fra