Moreover, the current results revealed that hypermethylation of genes involved in cell cycle regulation and apoptosis (CDKN2A, PYCARD, RASSF1), angiogenesis and metastasis (THBS1), DNA repair (BRCA1, MGMT), histone methylation (GSTP) and tumor suppressor genes (PTEN, HIC1) were significantly associated with worse DFS and OS rates in the whole group of BC patients. The gene discussed is RASSF1; the disease is breast cancer.