672

BRCA1

breast cancer 1, early onset;BRCA1;breast cancer 1, early onset

BRCA1/BRCA2-containing complex, subunit 1|Fanconi anemia, complementation group S|RING finger protein 53|breast and ovarian cancer susceptibility protein 1|breast and ovarian cancer sususceptibility protein 1|breast cancer type 1 susceptibility protein|pr

17q21

protein-coding

BACKGROUND: Data on distant disease-free interval (DDFI) and the localization of the first distant metastasis (DM) in BRCA1- and BRCA2-associated breast cancer (BC) patients are as yet scarcely available. PATIENTS AND METHODS: We identified 57 BRCA1-associated and 31 BRCA2-associated BC patients, diagnosed between 1980 and 2001, and developing DM disease before 2004, July 1. DDFI, the site(s) of first DM and post-relapse survival of these patients were compared with those of 192 sporadic BC patients. RESULTS: As compared to sporadic patients, BRCA1 patients developed less often bone DM (30% vs. 51%; P = 0.005), but tended to develop more often lung DM (26% vs. 16%; P = 0.07), and DM at multiple sites (44% vs. 32%; P = 0.11). In BRCA2-associated compared to sporadic patients, first DM more commonly occurred in lymph nodes (23% vs. 7%; P = 0.007) and at multiple sites (48% vs. 32%; P = 0.08). Adjuvant systemic therapy appeared to be most effective in BRCA2 mutation carriers. Post-relapse survival was worse for BRCA1- and better for BRCA2-associated patients as compared to sporadic patients, but differences disappeared after adjustment for ER-status, site of first DM and DDFI. CONCLUSION: The site of first DM is different between BRCA1- and BRCA2-associated and sporadic BC patients. Differences in post-relapse survival could be explained by differences in site of first DM, in ER-status and in DDFI. Treatment efficacy may differ dependent on genetic status.

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.

Aberrant hypermethylation of gene promoter regions is one of the mechanisms for inactivation of tumour suppressor genes in many human cancers including breast carcinoma. In the current study, we aimed to assess by MSP, the methylation pattern of two cancer-related genes involved in DNA repair: hMLH1 (mutL homolog 1, colon cancer, nonpolyposis type 2 (E. coli) and BRCA1 (breast cancer 1, early onset) in 78 primary breast cancers from Tunisian patients. The methylation frequencies were 24.36% for hMLH1 and 46% for BRCA1. BRCA1 methylation correlated with age at diagnosis (P = .015) and 5-years disease free survival (P = .016) while hMLH1 methylation was more frequent in larger tumors (P = .002) and in presence of distant metastasis (P = .004). Furthermore, methylation of hMLH1 significantly correlated with high level of P53 expression (P = .006) and with overall survival (P = .015) suggesting that silencing of hMLH1 through aberrant promoter methylation could be used as a poor prognosis indicator in breast cancer.

Breast cancer-associated 1 (BRCA1) plays an important role in breast cancer initiation and progression through its functions in the cell cycle and DNA repair processes; however, its role in metastatic development in human breast cancer is still poorly understood. We have previously shown that osteopontin (OPN) expression was suppressed by wild-type BRCA1 (Wt.BRCA1) and that a natural mutant allele of BRCA1 (Mut.BRCA1) diminished the effect of Wt.BRCA1 on OPN in vitro. In this study, we show that while Wt.BRCA1 suppresses OPN-induced metastasis in a rat syngeneic system, Mut.BRCA1 enhances the development of metastasis through OPN, suggesting that OPN and BRCA1 work closely to regulate metastatic development in the rat. To test whether these findings are relevant to human breast cancer, we have investigated the relationship between BRCA1, OPN, and metastatic properties in human breast cancer-related cells. Using western blot analysis, we show that Wt.BRCA1 suppresses, while Mut.BRCA1 enhances, OPN protein expression; and in parallel that Wt.BRCA1 suppresses, while Mut.BRCA1 enhances, OPN-mediated in vitro properties associated with the metastatic state in both MCF-7 and MDA MB435s cells. Overall, these results suggest that Mut.BRCA1 can elicit some of the changes involved in metastatic progression in human breast cancer via the overexpression of OPN.

OBJECTIVE: To explore the mRNA expression of breast cancer susceptibility gene 1 (BRCA1) in tumor cells isolated from malignant pleural and peritoneal effusions, and the predictive role of BRCA1 related to the efficacy of cisplatin-based chemotherapy. METHODS: tumor cells were isolated from malignant pleural and peritoneal effusions of 31 cancer patients. The response of these tumor cells to cisplatin was determined by CCK8 assay. Real time quantitative RT-PCR was used to examine the BRCA1 mRNA level in the primary culture cancer cells. RESULTS: The expression level of BRCA1 mRNA was 0.618 (0.014 - 18.063) in primary culture tumor cells. The IC(50) of DDP was 2.809 microg/ml in the primary culture tumor cells (0.118 - 19.439 microg/ml). Both BRCA1 mRNA expression and the tumor cells IC(50) of DDP were not significantly related with patient age, gender, the type of primary tumor, whether to accept the chemotherapy and effusion type (P > 0.05). The level of BRCA1 mRNA was negatively correlated with the chemosensitivity in terms of IC(50) of cisplatin (P < 0.001). CONCLUSION: Assessment of expression level of BRCA1 mRNA may be useful in predicting the efficacy of cisplatin-based chemotherapy in patients with metastatic malignant effusions.

Breast cancer is a complex disease; the molecular mechanisms involved in sporadic breast carcinogenesis remain to be elucidated. The present study aimed to explore the deficiency of breast cancer susceptibility gene 1 (BRCA1), including protein loss expression, promoter hypermethylation and gene copy deletion, its correlationship with other tumor markers expression (TP53, MYC, etc.), and clinical significance in sporadic breast cancer. BRCA1 protein expression was negative in 226 of 374 (60.4%) cases of this study. Cases negative for BRCA1 protein were more often with pathological tumor-node-metastasis stage III, positive for lymph node metastasis and MYC overexpression than BRCA1-positive tumors. BRCA1 hypermethylation was detected in 16.4% (31 of 189) breast cancers, which correlated with BRCA1 negative, ER negative, MYC overexpression, and triple-negative phenotype. In addition, the percentage of cells with BRCA1 gene copy deletion was significantly increased in BRCA1-methylated tumors. Kaplan-Meier survival analysis showed that patients with BRCA1-negative expression showed a worse overall survival (OS) than those with BRCA1-positive expression, and patients with BRCA1-methylated tumors had a significantly worse disease-free survival than did patients with unmethylated tumors. Furthermore, BRCA1 hypermethylation showed an inverse association with OS in LN-positive or p53-negative subgroup patients. Importantly, uni- and multivariate Cox regression analyses revealed that BRCA1 was an independent prognostic indicator of OS in sporadic breast cancer. Thus, we found MYC overexpression and poor prognosis in sporadic breast cancer with BRCA1 deficiency. The targeting of BRCA1 deficiency in combination with MYC-pathways inhibitors may provide a promising strategy for sporadic breast cancer care, the triple-negative subtype in particular.

BACKGROUND: Although both excision repair cross-complementing group 1 (ERCC1) and breast cancer susceptibility gene 1 (BRCA1) can be effective biomarkers for chemosensitivity in primary malignant tumors, their applicability to metastases is poorly understood. Here, ERCC1 and BRCA1, which are linked to lymph node metastasis (LNM) in colorectal cancer (CRC), were evaluated in primary CRC samples from Chinese patients with LNM (LNM CRC) or without LNM (non-LNM CRC). mRNA levels of ERCC1 and BRCA1 in CRC samples, and their relationships to primary CRC and LNM, were also examined. METHODS: Differences in BRCA1 and ERCC1 gene expression between primary CRC with or without LNM were assessed in CRC samples from 120 Chinese patients, using real-time polymerase chain reaction. Relationships between ERCC1 and BRCA1 expression and clinicopathological parameters and prognoses were also examined. RESULTS: ERCC1 and BRCA1 were significantly down-regulated in LNM CRC compared with non-LNM CRC. Down-expression of ERCC1 and BRCA1 was significantly associated with LNM (P < 0.001), advanced TNM stage (P < 0.001), and decreased 5-year overall survival rate (P < 0.001). Univariate and multivariate analyses showed ERCC1 and BRCA1 expression as independent predictors of recurrence and survival in CRC patients (P < 0.05). CONCLUSIONS: ERCC1 and BRCA1 mRNA expression levels correlate inversely to CRC metastasis. ERCC1 and BRCA1 might serve as biomarkers for LNM and as prognostic indicators for CRC; their down-expressions are predictors of poor outcome in CRC patients.

To investigate microsatellite instability (MSI) and loss of heterozygosity (LOH) of locus D17S396, D17S579 and D17S855, and their effect on the expression of nm23H1 and BRCA1 of gastric cancer, which would provide experimental basis for clinical treatment and prognosis analysis of gastric cancer. DNA was extracted from paraffin-embedded materials. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was used to analyze MSI and LOH. expression of nm23H, and BRCA1 was detected by Envision immuno-histochemistry and Leica-Qwin computer imaging techniques. In the forty cases of gastric cancer, the frequency of MSI, LOH and nm23H1 protein were 20.00%, 17.50% and 55.00% respectively at locus D17S396, while at locus D17S579, the frequency of MSI, LOH and BRCA1 protein were 22.50%, 15.00% and 37.50% respectively; at locus D17S855, the frequency of MSI, LOH and BRCA1 of thirty-seven cases were 18.92%, 18.92%, 37.84% respectively. In tumor node metastasis (TNM) staging, at locus D17S396, D17S579 and D17S855, MSI in stages I + II appeared more frequently than that in stages III + IV, while LOH appeared the contrary tendency. In the group of metastasis of gastric cancer, MSI had a less frequency (5.00%) than that with no metastasis (35.00%, P < 0.05) at locus D17S396, but LOH appeared more frequently (30.00%) than that with no metastasis (5.00%, P < 0.05). At locus D17S579, MSI had an increasing tendency with the degree of tumor differentiation (50.00% in high differentiation cases, 20.00% in middle differentiation cases, and 0% in low differentiation cases, P < 0.05). The frequency of nm23H1 and BRCA1 protein in stages TNM I + II was higher than that in stages TNM III + IV; and that in higher differentiation cases was higher than in poor differentiation cases. The frequency of nm23H1 protein in the group of metastasis (30.00%) was less than that with no metastasis significantly (80.00%, P<0.01). The frequency of nm23H1 protein in the group positive to MSI (87.50%) was higher than that in the group negative to MSI (46.88%, P < 0.05). However, nm23H1 protein in group positive to LOH (14.29%) was lower than that in the group negative to LOH (63.64%, P < 0.05). The frequency of BRCA1 protein in the group positive to MSI (66.67%) was more than that in the group negative to MSI (29.03%, P < 0.05). The results of experiments indicate that MSI and LOH may separately control the development of sporadic colon cancer with different pathways. MSI may be an early period molecule marker for sporadic colon cancer, enhanced expression of nm23H1 protein can effectively inhibit colon cancer metastasis and improve prognosis of sporadic colon cancer patients. By comparison, LOH mostly arises in the late period of sporadic colon cancer and endows a high aggressive and poor prognostic phenotype. nm23H1 protein could effectively restrain gastric cancer metastasis and development; and BRCA1 protein could restain tumor from becoming lower differentiation.

Breast cancer is a complex disease; the molecular mechanisms involved in sporadic breast carcinogenesis remain to be elucidated. The present study aimed to explore the deficiency of breast cancer susceptibility gene 1 (BRCA1), including protein loss expression, promoter hypermethylation and gene copy deletion, its correlationship with other tumor markers expression (TP53, MYC, etc.), and clinical significance in sporadic breast cancer. BRCA1 protein expression was negative in 226 of 374 (60.4%) cases of this study. Cases negative for BRCA1 protein were more often with pathological tumor-node-metastasis stage III, positive for lymph node metastasis and MYC overexpression than BRCA1-positive tumors. BRCA1 hypermethylation was detected in 16.4% (31 of 189) breast cancers, which correlated with BRCA1 negative, ER negative, MYC overexpression, and triple-negative phenotype. In addition, the percentage of cells with BRCA1 gene copy deletion was significantly increased in BRCA1-methylated tumors. Kaplan-Meier survival analysis showed that patients with BRCA1-negative expression showed a worse overall survival (OS) than those with BRCA1-positive expression, and patients with BRCA1-methylated tumors had a significantly worse disease-free survival than did patients with unmethylated tumors. Furthermore, BRCA1 hypermethylation showed an inverse association with OS in LN-positive or p53-negative subgroup patients. Importantly, uni- and multivariate Cox regression analyses revealed that BRCA1 was an independent prognostic indicator of OS in sporadic breast cancer. Thus, we found MYC overexpression and poor prognosis in sporadic breast cancer with BRCA1 deficiency. The targeting of BRCA1 deficiency in combination with MYC-pathways inhibitors may provide a promising strategy for sporadic breast cancer care, the triple-negative subtype in particular.

PURPOSE: To analyze the baseline clinicopathologic characteristics of prostate tumors with germline BRCA1 and BRCA2 (BRCA1/2) mutations and the prognostic value of those mutations on prostate cancer (PCa) outcomes. PATIENTS AND METHODS: This study analyzed the tumor features and outcomes of 2,019 patients with PCa (18 BRCA1 carriers, 61 BRCA2 carriers, and 1,940 noncarriers). The Kaplan-Meier method and Cox regression analysis were used to evaluate the associations between BRCA1/2 status and other PCa prognostic factors with overall survival (OS), cause-specific OS (CSS), CSS in localized PCa (CSS_M0), metastasis-free survival (MFS), and CSS from metastasis (CSS_M1). RESULTS: PCa with germline BRCA1/2 mutations were more frequently associated with Gleason >/= 8 (P = .00003), T3/T4 stage (P = .003), nodal involvement (P = .00005), and metastases at diagnosis (P = .005) than PCa in noncarriers. CSS was significantly longer in noncarriers than in carriers (15.7 v 8.6 years, multivariable analyses [MVA] P = .015; hazard ratio [HR] = 1.8). For localized PCa, 5-year CSS and MFS were significantly higher in noncarriers (96% v 82%; MVA P = .01; HR = 2.6%; and 93% v 77%; MVA P = .009; HR = 2.7, respectively). Subgroup analyses confirmed the poor outcomes in BRCA2 patients, whereas the role of BRCA1 was not well defined due to the limited size and follow-up in this subgroup. CONCLUSION: Our results confirm that BRCA1/2 mutations confer a more aggressive PCa phenotype with a higher probability of nodal involvement and distant metastasis. BRCA mutations are associated with poor survival outcomes and this should be considered for tailoring clinical management of these patients.