According to the results obtained from this study, genistein induces apoptosis and inhibits the proliferation of EJ138 BC cells by upregulating the expression of miR-27a, apoptosis-related genes (caspase 3 and caspase 9), and autophagy regulator genes (ATG12, Beclin1), while downregulating miR-151 expression. The gene discussed is CASP3; the disease is breast cancer.