GPX4 is markedly overexpressed in breast cancer, where its primary function is to neutralize reactive oxygen species (ROS) by converting glutathione (GSH) into its oxidized form, glutathione disulfide (GSSG) (Shi Z et al., 2021; Lin HY et al., 2021; Wang D et al., 2021). The gene discussed is GPX4; the disease is breast carcinoma.