Evaluation of BRCA1 Gene Promoter Methylation Status in Sporadic Breast Cancer Patients in Southwest of Iran

OBJECTIVE: Similar to other types of cancer, the development of breast cancer is a multi-stage process, consisting of various mutations and epigenetic changes in many genes. Mutations in the BRCA1 gene, which is a tumor suppressor gene, are considered as the most important types of mutations. The pivotal role of epigenetics is currently considered as the primary key to carcinogenesis. Several studies have previously reported the BRCA1 epigenetic silencing through promoter methylation in the pathophysiology of breast cancer cells. This study aimed to investigate whether the BRCA1 gene promoter methylation in peripheral blood cells is correlated with the risk of breast cancer. METHODS: In the current study, DNA samples were extracted from blood cells belonged to 74 patients with breast cancer as well as 30 healthy individuals, and the BRCA1 gene promoter methylation status in these two groups was examined using Methylation Specific PCR (MSP). RESULT: out of 74 patients, 2 cases demonstrated methylation in their BRCA1 gene promoter; however, none of the healthy controls demonstrated methylation status. Among these 74 patients, 13 cases were at the early stages (stage I), and two patients who had BRCA1 gene methylation (15.4%), were in this group (p=0.02). While 34 and 27 patients were at stages II and III, respectively, showing a negative state of BRCA1 gene methylation. CONCLUSION: Although 2 out of 74 patients resulted positive for methylation status, the healthy controls demonstrated no methylation. Consequently, there was inadequate evidence to confirm the association between BRCA1 gene promoter methylation in blood and the risk of developing breast cancer.