BRCA1

Gene Summary

Gene:BRCA1; breast cancer 1, early onset
Aliases: IRIS, PSCP, BRCAI, BRCC1, FANCS, PNCA4, RNF53, BROVCA1, PPP1R53
Location:17q21
Summary:This gene encodes a nuclear phosphoprotein that plays a role in maintaining genomic stability, and it also acts as a tumor suppressor. The encoded protein 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). This gene product 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. Alternative splicing plays a role in modulating the subcellular localization and physiological function of this gene. Many alternatively spliced transcript variants, some of which are disease-associated mutations, have been described for this gene, but the full-length natures of only some of these variants has been described. A related pseudogene, which is also located on chromosome 17, has been identified. [provided by RefSeq, May 2009]
Databases:OMIM, VEGA, HGNC, Ensembl, GeneCard, Gene
Protein:breast cancer type 1 susceptibility protein
HPRD
Source:NCBIAccessed: 16 March, 2015

Ontology:

What does this gene/protein do?
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Pathways:What pathways are this gene/protein implicaed in?
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Cancer Overview

BRCA1 is a breast cancer susceptibility gene that was first identified in 1994. People carrying a mutation (abnormality) in this gene are at an increased risk of breast or ovarian cancer. The normal gene plays a role in repairing breaks in DNA. However, when the gene is mutated it is thought that this repair function may become disabled thus leading to more DNA replication errors and cancerous growth.

Research Indicators

Publications Per Year (1990-2015)
Graph generated 16 March 2015 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

Tag cloud generated 16 March, 2015 using data from PubMed, MeSH and CancerIndex

Specific Cancers (10)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Entity Topic PubMed Papers
Breast CancerBRCA1 mutations in Breast Cancer View Publications3000
Ovarian CancerBRCA1 and Ovarian Cancer View Publications2715
-Genetic Counseling for people with BRAC1/BRCA2 mutations View Publications292
Breast Cancer, FamilialProphylactic Treatments for Women with BRCA1/BRAC2 mutations Therapy View Publications237
Prostate CancerBRCA1 and Prostate Cancer View Publications178
Breast Cancer185delAG mutation (c.68_69delAG) in BRCA1
The 185delAG mutation (c.68_69delAG; ter39) in the BRCA1 gene is a founder mutation carried by approximately 1% of the Jewish Ashkenazi population.
View Publications133
Colorectal CancerBRCA1 germliine mutation and increased risk of Colorectal Cancer?
There have been conflicting results regarding the risk of colorectal cancer confered by germline mutations of BRCA1 & BRCA2. In a follow-up study of 7015 women with a BRCA mutations Phelan et al (2014) found significantly increased risk of colorectal cancer in female carriers of BRCA1 mutations below the age of 50 years but not in women with BRCA2 mutations or in older women.
View Publications128
Fallopian tube cancerBRCA1 mutations in Fallopian Tube Cancer View Publications116
Cancer ScreeningBRCA1 and Cancer Screening View Publications96
Hereditary Breast and Ovarian Cancer SyndromeHereditary Breast and Ovarian Cancer Syndrome
An Autosomal dominant hereditary cancer syndrome in which a mutation most often in either BRCA1 or BRCA2 is associated with a significantly increased risk for breast and ovarian cancers. [MeSH]
View Publications57

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Latest Publications: BRCA1 (cancer-related)

King MC, Lahad A, Levy-Lahad E
Proposed shift in screening for breast cancer--reply.
JAMA. 2015; 313(5):525-6 [PubMed] Related Publications

Levine B, Steinberg K
Proposed shift in screening for breast cancer.
JAMA. 2015; 313(5):525 [PubMed] Related Publications

Cornejo-Moreno BA, Uribe-Escamilla D, Salamanca-Gómez F
Breast cancer genes: looking for BRACA's lost brother.
Isr Med Assoc J. 2014; 16(12):787-92 [PubMed] Related Publications
Breast cancer, specifically mammary carcinoma, is the most common cause of death from cancer in women worldwide, with a lifetime risk of one in nine, and its prevalence is increasing. It represents around 30% of all cancer in females and approximately 40,000 deaths in the United States per year. Important advances have been made in detection and treatment, but a significant number of breast cancers are still detected late. This summary of its epidemiology and history, the molecular aspects of detection and the main implicated genes emphasizes the etiology and heterogeneity of the disease. It is still not clear whether the remaining cases of breast cancer negative to BRCA are due to mutations in another high penetrance gene or to unknown factors yet to be discovered.

Pillar N, Shomron N
Breast cancer genomics in the deep sequencing era.
Isr Med Assoc J. 2014; 16(12):783-4 [PubMed] Related Publications

Levy-Lahad E, Lahad A, King MC
Precision medicine meets public health: population screening for BRCA1 and BRCA2.
J Natl Cancer Inst. 2015; 107(1):420 [PubMed] Related Publications

Popovska S, Ivanov I, Dineva T, et al.
[Morphologically qnd immunohistochemically based screening criteria for selection of patients with possible mutation of BRCA1 gene in primary ovarian cancer].
Akush Ginekol (Sofiia). 2014; 53(4):21-8 [PubMed] Related Publications
UNLABELLED: SUMMARY AND AIM: Breast cancer (BC) and Ovarian cancer (OC) are some of the most common cancers affecting women. Environmental factors and genetic alterations are involved in the etiology of both cancers. The main susceptibility genes that predisposed to BC and OC are BRCA1 (BReast CAncer 1) and BRCA 2 (BReast CAncer 2). Those of BC and OC which are due to germline mutation in BRCA 1/2 are defined as hereditary. Because of the expensiveness of genetic testing for mutations in BRCA1 we aimed to select patients with ovarian cancer suitable for genetic testing, on the base of certain morphological and immunohistochemical criteria.
MATERIAL AND METHODS: We have conducted a retrospective analysis of 29 cases with serous papillary OC, taken from the archives of the Department of Clinical Pathology, University Hospital "Dr. G. Stranski" Pleven. We performed morphological assessment and subsequent immunohistochemical study with antibodies against p53, anti BRCA1 and anti proliferative marker Ki-67.
RESULTS: Nineteen (65.52%) of all 29 cases were found with loss of immunohistochemical expression of BRCA1 and we defined them as suitable for genetic testing of BRCA1 mutations.
CONCLUSION: A set of morphological and immunohistochemical criteria allows screening of women that should be referred for genetic testing, as it is expensive, and the incidence of BRCA1 mutations in the general population is very low.

Couzin-Frankel J
Unknown significance.
Science. 2014; 346(6214):1167-70 [PubMed] Related Publications

Economopoulou P, Dimitriadis G, Psyrri A
Beyond BRCA: new hereditary breast cancer susceptibility genes.
Cancer Treat Rev. 2015; 41(1):1-8 [PubMed] Related Publications
Approximately 5-10% of breast cancer cases might be inheritable, up to 30% of which are due to BRCA1/2 mutations. During the past few years and thanks to technology evolution, we have been witnesses of an intensive search of additional genes with similar characteristics, under the premise that successful gene discovery will provide substantial opportunities for primary and secondary prevention of breast cancer. Consequently, new genes have emerged as breast cancer susceptibility genes, including rare germline mutations in high penetrant genes, such as TP53 and PTEN, and more frequent mutations in moderate penetrant genes, such as CHEK2, ATM and PALB2. This review will summarize current data on new findings in breast cancer susceptibility genes.

Ward A, Khanna KK, Wiegmans AP
Targeting homologous recombination, new pre-clinical and clinical therapeutic combinations inhibiting RAD51.
Cancer Treat Rev. 2015; 41(1):35-45 [PubMed] Related Publications
The DNA damage response (DDR) is essential for maintaining genomic stability and cell survival. However, when tumour cells with deficiencies in HR are faced with radio- and chemotherapies they are forced to rely on error-prone, alternative repair pathways or aberrant HR for survival; threatening genome integrity and driving further mutation. Accurate therapeutic targeting of the key drivers of DNA repair can circumvent survival pathways and avoid aggressive therapy resistant mutants. Several studies have identified that stabilization of the cancer genome in HR deficient cells can be achieved by overexpression of the recombinase RAD51. Radio- and chemotherapeutic resistance is associated with overactive HR repair mechanisms. However no clinical trials have directly targeted RAD51, despite RAD51 displaying synergy in several drug screens against multiple cancer types. Currently synthetic lethality targeting the DDR pathways and HR deficiency has had clinical success with BRCA1 functional loss and PARP inhibition. In this review we suggest that clinical outcomes could be improved by additionally targeting RAD51. We examine the latest developments in directly and indirectly targeting RAD51. We scrutinize the potential treatment efficacy and future clinical applications of RAD51 inhibitors as single agents and in combination with other therapies and consider the best therapeutic options.

Zhong Q, Shi G, Zhang Y, et al.
Alteration of BRCA1 expression affects alcohol-induced transcription of RNA Pol III-dependent genes.
Gene. 2015; 556(1):74-9 [PubMed] Article available free on PMC after 01/02/2016 Related Publications
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.

Olariu R, Shafighi M, Constantinescu MA
[The risk-reducing mastectomy: unnecessary hysteria or life-saving prophylaxis?].
Ther Umsch. 2014; 71(12):759-64 [PubMed] Related Publications
The prophylactic (risk-reducing) mastectomy is a world-wide recognized method for specifically treating the increased breast cancer risk in patients showing a BRCA1 and/or BRCA2 mutation as well as other patient groups at increased breast cancer risk. This option should be offered to all patients having the pertinent risk profile. Breast reconstruction is an integral part of the risk-reducing mastectomy procedure and all possible methods of breast reconstruction, especially autologous tissue reconstruction should be offered to all patients having a medical indication and desiring this surgical treatment. These patients are best managed in certified Breast Care Centres where the different medical and surgical specialists can address interdisciplinary all aspects of genetic counselling, preoperative counselling, mastectomy and reconstructive techniques as well as the necessary postoperative surveillance.

Erturk E, Cecener G, Tezcan G, et al.
BRCA mutations cause reduction in miR-200c expression in triple negative breast cancer.
Gene. 2015; 556(2):163-9 [PubMed] Related Publications
Triple negative breast cancer (TNBC) is the most aggressive and poorly understood subclass of breast cancer (BC). Over the recent years, miRNA expression studies have been providing certain detailed overview that aberrant expression of miRNAs is associated with TNBC. Although TNBC tumors are strongly connected with loss of function of BRCA genes, there is no knowledge about the effect of BRCA mutation status on miRNA expressions in TNBC cases. The aims of this study were to evaluate the expression profile of miRNAs that plays role in TNBC progression and the role of BRCA mutations in their regulation. The expression level of BC associated 13 miRNAs was analyzed in 7 BRCA mutations positive, 6 BRCA mutations negative TNBC cases and 20 non-tumoral tissues using RT-PCR. According to RT2 Profiler PCR Array Data Analysis, let-7a expression was 4.67 fold reduced in TNBCs as compared to normal tissues (P=0.031). In addition, miR-200c expression was 5.75 fold reduced in BRCA mutation positive TNBC tumors (P=0.005). Analysis revealed a negative correlation between miR-200c and VEGFA expressions (r=-468). Thus, miR-200c may be involved in invasion and metastasis in TNBC cases with BRCA mutation. In this study we provide the knowledge on the first report of association between microRNA-200c and BRCA mutations in TNBC. Further studies and evaluations are required, but this miRNA may provide novel therapeutic molecular targets for TNBC treatment and new directions for the development of anticancer drugs.

Pernin V, Mégnin-Chanet F, Pennaneach V, et al.
[PARP inhibitors and radiotherapy: rational and prospects for a clinical use].
Cancer Radiother. 2014; 18(8):790-8; quiz 799-802 [PubMed] Related Publications
Poly(ADP-ribosyl)ation is a ubiquitous protein modification involved in the regulation of many cellular processes that is carried out by the poly(ADP-ribose) polymerase (PARP) family. The PARP-1, PARP-2 and PARP-3 are the only PARPs known to be activated by DNA damage. The absence of PARP-1 and PARP-2, that are both activated by DNA damage and participate in DNA damage repair processes, results in hypersensitivity to ionizing radiation and alkylating agents. PARP inhibitors that compete with NAD(+) at the enzyme's activity site can be used in BRCA-deficient cells as single agent therapies acting through the principle of synthetic lethality exploiting these cells deficient DNA double-strand break repair. Preclinical data showing an enhancement of the response of tumors to radiation has been documented for several PARP inhibitors. However, whether this is due exclusively to impaired DNA damage responses or whether tumor re-oxygenation contributes to this radio-sensitization via the vasoactive effects of the PARP inhibitors remains to be fully determined. These promising results have paved the way for the evaluation of PARP inhibitors in combination with radiotherapy in phase I and phase II clinical trials for malignant glioma, head and neck, and breast cancers. A number of challenges remain that are also reviewed in this article, including the optimization of treatment schedules for combined therapies and the validation of biomarkers that will identify which patients will most benefit from either PARP inhibitors in combination with radiotherapy.

Manchanda R, Legood R, Burnell M, et al.
Cost-effectiveness of population screening for BRCA mutations in Ashkenazi jewish women compared with family history-based testing.
J Natl Cancer Inst. 2015; 107(1):380 [PubMed] Article available free on PMC after 01/02/2016 Related Publications
BACKGROUND: Population-based testing for BRCA1/2 mutations detects the high proportion of carriers not identified by cancer family history (FH)-based testing. We compared the cost-effectiveness of population-based BRCA testing with the standard FH-based approach in Ashkenazi Jewish (AJ) women.
METHODS: A decision-analytic model was developed to compare lifetime costs and effects amongst AJ women in the UK of BRCA founder-mutation testing amongst: 1) all women in the population age 30 years or older and 2) just those with a strong FH (≥10% mutation risk). The model assumes that BRCA carriers are offered risk-reducing salpingo-oophorectomy and annual MRI/mammography screening or risk-reducing mastectomy. Model probabilities utilize the Genetic Cancer Prediction through Population Screening trial/published literature to estimate total costs, effects in terms of quality-adjusted life-years (QALYs), cancer incidence, incremental cost-effectiveness ratio (ICER), and population impact. Costs are reported at 2010 prices. Costs/outcomes were discounted at 3.5%. We used deterministic/probabilistic sensitivity analysis (PSA) to evaluate model uncertainty.
RESULTS: Compared with FH-based testing, population-screening saved 0.090 more life-years and 0.101 more QALYs resulting in 33 days' gain in life expectancy. Population screening was found to be cost saving with a baseline-discounted ICER of -£2079/QALY. Population-based screening lowered ovarian and breast cancer incidence by 0.34% and 0.62%. Assuming 71% testing uptake, this leads to 276 fewer ovarian and 508 fewer breast cancer cases. Overall, reduction in treatment costs led to a discounted cost savings of £3.7 million. Deterministic sensitivity analysis and 94% of simulations on PSA (threshold £20000) indicated that population screening is cost-effective, compared with current NHS policy.
CONCLUSION: Population-based screening for BRCA mutations is highly cost-effective compared with an FH-based approach in AJ women age 30 years and older.

Manchanda R, Loggenberg K, Sanderson S, et al.
Population testing for cancer predisposing BRCA1/BRCA2 mutations in the Ashkenazi-Jewish community: a randomized controlled trial.
J Natl Cancer Inst. 2015; 107(1):379 [PubMed] Article available free on PMC after 01/02/2016 Related Publications
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't adversely affect short-term psychological/quality-of-life outcomes and may detect 56% additional BRCA carriers.

Arai M, Iwase T, Takazawa Y, Takeshima N
[Current clinical issues and recent trends in hereditary breast and ovarian cancer in Japan-genetic testing for HBOC and risk-reducing surgery].
Gan To Kagaku Ryoho. 2014; 41(11):1333-9 [PubMed] Related Publications
The recognition of hereditary breast and ovarian cancer (HBOC) is gradually spreading in Japan after a famous American actress made it public that she underwent risk-reducing mastectomy (RRM) based on mutation of BRCA1. HBOC is a cancer susceptibility syndrome involving breast, ovarian, or prostate cancers due to germline mutation of BRCA1 or BRCA2. Although the frequency is low, genomic rearrangement is also found in Japan; therefore, in addition to PCR-direct sequencing, multiplex ligation-dependent probe amplification (MLPA) should be performed in genetic testing for HBOC. Recently, candidate genes other than BRCA1/2, such as RAD51C, PALB2, and BRIP1, have been identified for hereditary breast cancers. Variants of uncertain significance are seen in approximately 4-6% of all genetic testing reports for BRCA1/2. ACMG recommends the use of the term"variant"in addition to a modifier such as pathogenic, benign, and so on, instead of terms such as mutation or polymorphism. The incidence of ovarian cancer is not increased in women from breast cancer-only families that test negative for BRCA1/2 mutations. Therefore, intensive gynecological surveillance may not be needed for these clients. Basic data such as penetrance and cumulative risks of HBOC in Japanese populations are insufficient for risk assessment in genetic counseling. The Japanese HBOC consortium was established, and as one of the activities of the consortium, the registration project will start to provide essential genetic information in clinical practice. In Japan risk-reducing surgeries are, albeit gradually, increasingly being performed to potentially protect mutation carriers against HBOC. Risk-reducing salpingo-oophorectomy (RRSO) is effective in the reduction of the incidence of breast cancer, as well as of ovarian cancer. Furthermore, RRSO is associated with improved overall survival in BRCA1/2 mutation carriers. RRM also reduces the risk of breast cancer by more than 90%, but the survival benefit remains unknown. Recently, contralateral RRM has shown improved overall survival in a prospective analysis. Pathological examination of resected surgical specimens from RRSO revealed that some serous ovarian carcinomas originated from fimbriae of the uterine tube, showing focal p53 overexpression (p53 signature) in the tubal epithelium. Therefore, initial bilateral salpingectomy followed by a delayed oophorectomy may be a proposed alternative to RRSO, but there is no prospective evidence on the efficacy of bilateral salpingectomy.

Rich TA, Woodson AH, Litton J, Arun B
Hereditary breast cancer syndromes and genetic testing.
J Surg Oncol. 2015; 111(1):66-80 [PubMed] Related Publications
Only 5% of breast cancers are explained by highly penetrant multisystem autosomal dominant hereditary disorders. Though another 20-30% has a familial presentation, the genetic and other etiologies are still not well understood. Genetic testing is now widely available and multiple professional societies have published guidelines for testing and management. Genetic testing trends include utilization of multi-gene panels that take advantage of next-generation sequencing as well as testing for low- and moderate-penetrance susceptibility genes.

Ottini L
Male breast cancer: a rare disease that might uncover underlying pathways of breast cancer.
Nat Rev Cancer. 2014; 14(10):643 [PubMed] Related Publications
There are similarities between breast cancers that arise in men and women but there are also differences. What can be learned from male breast cancer to gain insight into breast cancer pathogenesis?

Kinney AY, Butler KM, Schwartz MD, et al.
Expanding access to BRCA1/2 genetic counseling with telephone delivery: a cluster randomized trial.
J Natl Cancer Inst. 2014; 106(12) [PubMed] Article available free on PMC after 01/12/2015 Related Publications
BACKGROUND: The growing demand for cancer genetic services underscores the need to consider approaches that enhance access and efficiency of genetic counseling. Telephone delivery of cancer genetic services may improve access to these services for individuals experiencing geographic (rural areas) and structural (travel time, transportation, childcare) barriers to access.
METHODS: This cluster-randomized clinical trial used population-based sampling of women at risk for BRCA1/2 mutations to compare telephone and in-person counseling for: 1) equivalency of testing uptake and 2) noninferiority of changes in psychosocial measures. Women 25 to 74 years of age with personal or family histories of breast or ovarian cancer and who were able to travel to one of 14 outreach clinics were invited to participate. Randomization was by family. Assessments were conducted at baseline one week after pretest and post-test counseling and at six months. Of the 988 women randomly assigned, 901 completed a follow-up assessment. Cluster bootstrap methods were used to estimate the 95% confidence interval (CI) for the difference between test uptake proportions, using a 10% equivalency margin. Differences in psychosocial outcomes for determining noninferiority were estimated using linear models together with one-sided 97.5% bootstrap CIs.
RESULTS: Uptake of BRCA1/2 testing was lower following telephone (21.8%) than in-person counseling (31.8%, difference = 10.2%, 95% CI = 3.9% to 16.3%; after imputation of missing data: difference = 9.2%, 95% CI = -0.1% to 24.6%). Telephone counseling fulfilled the criteria for noninferiority to in-person counseling for all measures.
CONCLUSIONS: BRCA1/2 telephone counseling, although leading to lower testing uptake, appears to be safe and as effective as in-person counseling with regard to minimizing adverse psychological reactions, promoting informed decision making, and delivering patient-centered communication for both rural and urban women.

Connell TF
Patient-activated controlled expansion for breast reconstruction using controlled carbon dioxide inflation: confirmation of a feasibility study.
Plast Reconstr Surg. 2014; 134(4):503e-11e [PubMed] Related Publications
BACKGROUND: Women with breast cancer or those at high risk of developing breast cancer because of familial history of the disease or genetic mutations are frequently indicated for therapeutic or prophylactic mastectomy. Prosthetic reconstruction of the breast with placement of tissue expanders followed by implants offers favorable aesthetic and psychological results while adding only minimal additional surgical intervention. This study describes the confirmatory phase of an earlier feasibility trial that involved seven women who successfully underwent patient-activated controlled expansion for breast reconstruction with 10 AeroForm patient-controlled tissue expanders.
METHODS: A prospective, open-label, single-arm, single-surgeon confirmatory study in Perth, Australia, evaluated outcomes of two-stage breast reconstruction using the investigational device. Each subject administered a preset 10-cc dose of carbon dioxide gas using a remote dosage controller, three times each day, with a 3-hour lockout between doses until full expansion was achieved.
RESULTS: Thirty-three women with breast cancer, family history, or predisposition because of the BRCA1 or BRCA2 gene mutation underwent pedicled latissimus dorsi flap procedures with placement of 61 carbon dioxide-based tissue expanders. The mean number of days for subjects to achieve desired expansion was 17 ± 5. Operating the dosage controller was described by the surgeon as very easy in 94 percent of the cases and by 97 percent of the subjects. No serious adverse events were reported.
CONCLUSION: This study confirms that the AeroForm breast tissue expander has demonstrated the ability to provide, relative to saline expanders, a needle-free, patient-controlled, convenient, and time-saving method of tissue expansion.
CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Freund R, Kelsberg G, Safranek S
Clinical Inquiry: do oral contraceptives put women with a family history of breast cancer at increased risk?
J Fam Pract. 2014; 63(9):540, 549 [PubMed] Related Publications
A systematic review of the effect of combined OCPs on women with a family history of breast cancer found no additional increase in risk. Investigators identified 3 retrospective cohort studies (N=66,500, with 8500 cases) and 7 case-control studies (total 10,500 cases) from the past 40 years, most including women from the United States and Canada, but one including women from 5 continents.

Kelly PA, Connors LM
BRCA genetic testing: State of the science.
Nurse Pract. 2014; 39(11):9 [PubMed] Related Publications

Burdak-Rothkamm S, Rothkamm K, McClelland K, et al.
BRCA1, FANCD2 and Chk1 are potential molecular targets for the modulation of a radiation-induced DNA damage response in bystander cells.
Cancer Lett. 2015; 356(2 Pt B):454-61 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
Radiotherapy is an important treatment option for many human cancers. Current research is investigating the use of molecular targeted drugs in order to improve responses to radiotherapy in various cancers. The cellular response to irradiation is driven by both direct DNA damage in the targeted cell and intercellular signalling leading to a broad range of bystander effects. This study aims to elucidate radiation-induced DNA damage response signalling in bystander cells and to identify potential molecular targets to modulate the radiation induced bystander response in a therapeutic setting. Stalled replication forks in T98G bystander cells were visualised via bromodeoxyuridine (BrdU) nuclear foci detection at sites of single stranded DNA. γH2AX co-localised with these BrdU foci. BRCA1 and FANCD2 foci formed in T98G bystander cells. Using ATR mutant F02-98 hTERT and ATM deficient GM05849 fibroblasts it could be shown that ATR but not ATM was required for the recruitment of FANCD2 to sites of replication associated DNA damage in bystander cells whereas BRCA1 bystander foci were ATM-dependent. Phospho-Chk1 foci formation was observed in T98G bystander cells. Clonogenic survival assays showed moderate radiosensitisation of directly irradiated cells by the Chk1 inhibitor UCN-01 but increased radioresistance of bystander cells. This study identifies BRCA1, FANCD2 and Chk1 as potential targets for the modulation of radiation response in bystander cells. It adds to our understanding of the key molecular events propagating out-of-field effects of radiation and provides a rationale for the development of novel molecular targeted drugs for radiotherapy optimisation.

Chikarmane SA, Tirumani SH, Howard SA, et al.
Metastatic patterns of breast cancer subtypes: what radiologists should know in the era of personalized cancer medicine.
Clin Radiol. 2015; 70(1):1-10 [PubMed] Related Publications
There is accumulating evidence that molecular phenotyping of breast cancer determines the timing, pattern, and outcome of metastatic disease. The most clinically relevant subtypes are hormonal-positive [oestrogen and progesterone receptor (ER/PR) positive], HER2 expressing, and triple-negative breast cancers (TNBCs). ER/PR-positive breast cancers demonstrate the best prognosis; however, metastases, in particular osseous disease, may develop much later. HER2-expressing breast cancers, although aggressive, have improved outcomes due to the advent of HER2-targeted therapies, with increased risk of central nervous system (CNS) relapses later. Finally, TNBCs present in younger women, BRCA1 mutations carriers, and carry the worst overall prognosis, with high incidence of CNS metastases, especially during the first 5 years of diagnosis. It is important for radiologists to understand the nuances of these breast cancer subtypes to predict metastatic behaviours and guide possible imaging surveillance.

King MC
Lasker Award winner Mary-Claire King.
Nat Med. 2014; 20(10):1124-5 [PubMed] Related Publications

Ross L, Chung K, Macdonald H
Fertility preservation in the female cancer patient.
J Surg Oncol. 2014; 110(8):907-11 [PubMed] Related Publications
Hundreds of thousands of young women are diagnosed with cancer each year, but due to advances in screening, diagnosis, and treatment, survival rates have improved dramatically. With improved survival, long-term effects of cancer treatment including infertility need to be addressed and should be discussed as soon as possible. Oncologists should be familiar with their patients' risks of infertility and available options for fertility preservation and future reproduction.

Brett-Morris A, Wright BM, Seo Y, et al.
The polyamine catabolic enzyme SAT1 modulates tumorigenesis and radiation response in GBM.
Cancer Res. 2014; 74(23):6925-34 [PubMed] Related Publications
Glioblastoma multiforme (GBM) is the most common and severe form of brain cancer. The median survival time of patients is approximately 12 months due to poor responses to surgery and chemoradiation. To understand the mechanisms involved in radioresistance, we conducted a genetic screen using an shRNA library to identify genes in which inhibition would sensitize cells to radiation. The results were cross-referenced with the Oncomine and Rembrandt databases to focus on genes that are highly expressed in GBM tumors and associated with poor patient outcomes. Spermidine/spermine-N1-acetyltransferase 1 (SAT1), an enzyme involved in polyamine catabolism, was identified as a gene that promotes resistance to ionizing radiation (IR), is overexpressed in brain tumors, and correlates with poor outcomes. Knockdown of SAT1 using shRNA and siRNA approaches in multiple cell and neurosphere lines resulted in sensitization of GBM cells to radiation in colony formation assays and tumors, and decreased tumorigenesis in vivo. Radiosensitization occurred specifically in G2-M and S phases, suggesting a role for SAT1 in homologous recombination (HR) that was confirmed in a DR-GFP reporter system. Mechanistically, we found that SAT1 promotes acetylation of histone H3, suggesting a new role of SAT1 in chromatin remodeling and regulation of gene expression. In particular, SAT1 depletion led to a dramatic reduction in BRCA1 expression, explaining decreased HR capacity. Our findings suggest that the biologic significance of elevated SAT1 expression in GBM lies in its contribution to cell radioresistance and that SAT1 may potentially be a therapeutic target to sensitize GBM to cancer therapies.

van der Wijst MG, Brown R, Rots MG
Nrf2, the master redox switch: the Achilles' heel of ovarian cancer?
Biochim Biophys Acta. 2014; 1846(2):494-509 [PubMed] Related Publications
Ovarian cancer is the most lethal gynecological tumor type in the world due to late stage detection, and resistance to chemotherapy. Therefore, alternative additional therapies are required. The etiology of ovarian cancer remains largely unknown, but risk factors point toward an important role for oxidative stress. Both healthy and tumor cells can cope with oxidative stress by activating the transcription factor Nrf2 (also known as Nfe2l2), the master regulator of antioxidant and cytoprotective genes. Indeed, for most ovarian cancers, aberrant activation of Nrf2 is observed, which is often associated with a copy number loss within the Nrf2-inhibitory complex KEAP1-CUL3-RBX1. A key role for Nrf2 in ovarian carcinogenesis has been validated by siRNA studies. However, to exploit the Nrf2 pathway for therapeutic interventions, potential side-effects should be minimized. In this review, we explore ovarian cancer specific factors with links to aberrant activity of Nrf2, to be exploited in future combination strategies, synergistic with direct Nrf2 inhibitory drugs. Particularly, we propose to stratify patients based on common ovarian cancer mutations (KRAS, BRAF, ERBB2, BRCA1 and its link with estradiol, TP53) for future NRF2 targeting strategies.

Bai F, Chan HL, Scott A, et al.
BRCA1 suppresses epithelial-to-mesenchymal transition and stem cell dedifferentiation during mammary and tumor development.
Cancer Res. 2014; 74(21):6161-72 [PubMed] Related Publications
BRCA1 mutation carriers are predisposed to developing basal-like breast cancers with high metastasis and poor prognosis. Yet, how BRCA1 suppresses formation of basal-like breast cancers is still obscure. Deletion of p18(Ink4c) (p18), an inhibitor of CDK4 and CDK6, functionally inactivates the RB pathway, stimulates mammary luminal stem cell (LSC) proliferation, and leads to spontaneous luminal tumor development. Alternately, germline mutation of Brca1 shifts the fate of luminal cells to cause luminal-to-basal mammary tumor transformation. Here, we report that disrupting Brca1 by either germline or epithelium-specific mutation in p18-deficient mice activates epithelial-to-mesenchymal transition (EMT) and induces dedifferentiation of LSCs, which associate closely with expansion of basal and cancer stem cells and formation of basal-like tumors. Mechanistically, BRCA1 bound to the TWIST promoter, suppressing its activity and inhibiting EMT in mammary tumor cells. In human luminal cancer cells, BRCA1 silencing was sufficient to activate TWIST and EMT and increase tumor formation. In parallel, TWIST expression and EMT features correlated inversely with BRCA1 expression in human breast cancers. Together, our findings showed that BRCA1 suppressed TWIST and EMT, inhibited LSC dedifferentiation, and repressed expansion of basal stem cells and basal-like tumors. Thus, our work offers the first genetic evidence that Brca1 directly suppresses EMT and LSC dedifferentiation during breast tumorigenesis.

Lancaster JM, Powell CB, Chen LM, et al.
Society of Gynecologic Oncology statement on risk assessment for inherited gynecologic cancer predispositions.
Gynecol Oncol. 2015; 136(1):3-7 [PubMed] Related Publications
Women with germline mutations in the cancer susceptibility genes, BRCA1 or BRCA2, associated with Hereditary Breast & Ovarian Cancer syndrome, have up to an 85% lifetime risk of breast cancer and up to a 46% lifetime risk of ovarian, tubal, and peritoneal cancers. Similarly, women with mutations in the DNA mismatch repair genes, MLH1, MSH2, MSH6, or PMS2, associated with the Lynch/Hereditary Non-Polyposis Colorectal Cancer (HNPCC) syndrome, have up to a 40-60% lifetime risk of both endometrial and colorectal cancers as well as a 9-12% lifetime risk of ovarian cancer. Mutations in other genes including TP53, PTEN, and STK11 are responsible for hereditary syndromes associated with gynecologic, breast, and other cancers. Evaluation of the likelihood of a patient having one of these gynecologic cancer predisposition syndromes enables physicians to provide individualized assessments of cancer risk, as well as the opportunity to provide tailored screening and prevention strategies such as surveillance, chemoprevention, and prophylactic surgery that may reduce the morbidity and mortality associated with these syndromes. Evaluation for the presence of a hereditary cancer syndrome is a process that includes assessment of clinical and tumor characteristics, education and counseling conducted by a provider with expertise in cancer genetics, and may include genetic testing after appropriate consent is obtained. This commentary provides guidance on identification of patients who may benefit from assessment for the presence of a hereditary breast and/or gynecologic cancer syndrome.

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Cite this page: Cotterill SJ. BRCA1, Cancer Genetics Web: http://www.cancer-genetics.org/BRCA1.htm Accessed:

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