Several pathways have been reported to regulate the activation of ferroptosis, including those regulated by the cyst(e)in/glutathione peroxidase-4 (GPX4), ferroptosis suppressor protein-1 (FSP1)/coenzyme Q10 (ref. 10) and FSP1/Vitamin K hydroquinone (VKH2)11. Here, GPX4 is linked to cyst.