In Western populations, 5 to 10 % of breast cancer cases can be attributed to major genetic factors such as BRCA1 and BRCA2, while this attribution is not yet well defined among Africans.
A modest inverse association between breast cancer and reported current alcohol consumption was observed among women with a BRCA1 mutation (OR = 0.82, 95% CI 0.70-0.96), but not among women with a BRCA2 mutation (OR = 1.00; 95% CI 0.71-1.41).
Consequently, we investigated the effects of equol on DNA methylation of breast cancer susceptibility genes (BRCA1 and BRCA2) and oncosuppressors in breast cancer cell lines (MDA-MB-231 and MCF-7) and in a dystrophic breast cell line (MCF-10a) following exposure to S-equol (2 μm) for 3 weeks.
Furthermore, for women with an established breast cancer whether their mutation directly influences (1) baseline prognosis, (2) the results of local surgical and radiation therapy, (3) the benefits from adjuvant systemic therapy and finally (4) whether selection or avoidance of particular systemic agents is guided by the presence of a BRCA1 or BRCA2 germline mutation?
Our study confirmed BRCA2p.Ile3412Val is presented in >2% of unaffected women and is likely benign, and BRCA2p.Ala1996Thr which is predicted to be likely pathogenic by in-silico models is presented in 2% of healthy Indian women suggesting that it may not be associated with breast cancer risk.
To characterize the biological features of breast cancer associated with germ-line mutations in BRCA1 and BRCA2, invasive tumors were studied from 58 Jewish women ascertained through studies of early-onset breast cancer.
In most Western populations, 5-10% of all breast cancer cases can be attributed to major genetic factors such as predisposing mutations in BRCA1 and BRCA2, with early-onset cases generally considered as an indicator of genetic susceptibility.
Germline mutations in the BRCA1 and BRCA2 genes in patients with early-onset breast cancer have not been clearly identified within the Algerian population.
Early age at diagnosis of breast cancer, ovarian cancer, bilateral breast cancer were associated with BRCA1, whereas male breast cancer and four or more breast cancer cases in the family were associated with BRCA2.
Much has been learned during the past decade about the genetic epidemiology of breast cancer, the ethnic distribution and clinical consequences of BRCA1 and BRCA2 mutations, and the central role of DNA repair in breast cancer susceptibility.
The term-pregnancies number was a significant risk-reducing factor for breast cancers in BRCA1 mutation carriers (HR per pregnancy, 0.640; 95% CI, 0.508-0.806; P < .001), for breast cancers in BRCA2 mutation carriers (HR per pregnancy, 0.534; 95% CI, 0.419-0.681; P < .001), and for ovarian cancers for BRCA1 mutation carriers (HR per pregnancy, 0.625; 95% CI, 0.474-0.824; P = .001).
Genetic defects in breast cancer (BC) susceptibility genes, most importantly BRCA1 and BRCA2, account for ~40% of hereditary BC and ovarian cancer (OC).
Of 1054 BRCA-negative, high-risk Hispanic women, 4.5% carried a PV in a cancer susceptibility gene, increasing understanding of hereditary BC in this population.
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.
Five cases carried the BRCA1 C4446T mutation and two cases carried the BRCA28765delAG mutation which are the most common mutations that have been described in French Canadian breast cancer and breast ovarian cancer families.
Recent evidence for the interactions of ataxia-telangiectasia mutated protein ATM and breast cancer susceptibility proteins BRCA1 and BRCA2 (identified as FANCD1) with other known FA proteins suggests that FA proteins have a significant role in DNA repair/recombination and cell cycle control.
Surveillance of the ovaries is recommended in BRCA1 and BRCA2-mutation carriers, in members from breast/ovarian cancer families and in some centres in 'breast cancer only' families with an early onset of breast cancer.