Correlation analysis demonstrated that only MBD2 has negative regulatory role on BRCA1 gene expression as well as in protein expression in ER+, PR+ & Triple negative breast cancer cells; its MBD2-BRCA1 axis indicates their significant role in the induction of apoptosis and reduction of sphere formation, colony formation, and metastasis in Breast cancer cells (Fig. 7). This evidence concerns the gene BRCA1 and breast cancer.