Epigenetic Inheritance of Breast Cancer

摘要

Hypermethylation of tumor suppressor genes is only thought to occur in the somatic cell in sporadic tumors. However, we propose that methylation of the promoter of tumor suppressor genes, such as BRCA1, may also occur in the germ-line. Germ-line inheritance of this epigenetic silent state would therefore contribute to familial breast cancer. In this study we aimed to address if methylation of the tumor suppressor gene BRCA1 is inherited through the germ-line and is associated with the hereditary breast cancer. We developed a high-throughput sensitive real-time methylation assay that allowed us to screen for BRCA1 methylated DNA. We used this assay to screen for BRCA1 methylation from DNA isolated from archival blood and biopsy samples of women that have a family history of breast cancer but have no defined BRCA1 or BRCA2 mutations.