The role of xCT, as a facilitator of cyst(e)ine protective antioxidant role in cancer cells, is evidenced by the regulation of its expression by Nrf2 (111) and by signaling pathways activated by oxidative stress, including PI3K/AKT/mTOR (56, 112, 113) and MAPK pathways (110). The gene discussed is PIK3CG; the disease is cancer.