It is shown that estrogen (E2) acts through the PI3K-AKT pathway to regulate the activation of Nrf2 in BRCA1-deficient cells (126, 127), thereby inducing the production of antioxidant genes including GCLM and HO-1, protecting cells from ROS-induced death and enabling the survival of BC cells (128). The gene discussed is BRCA1; the disease is breast cancer.