PARK7 inhibits the activation of MAP3K5 by forming the PARK7/MAP3K5 complex under conditions of mild oxidative stress in order to protect against chemotherapy-induced oxidative stress that leads to apoptosis and autophagy in various cancer cells, including human osteosarcoma, colon cancer, hepatocellular carcinoma, and oral epidermoid carcinoma cells. The gene discussed is PARK7; the disease is osteosarcoma.