GPX4 and psoriasis: We found that the accumulation of pro-ferroptotic oxidized arachidonic acid–PE (oxPE) species in keratin 14–expressing (K14-expressing) KCs of the epidermis is a prominent feature of psoriasis, and is accompanied by downregulation of glutathione peroxidase 4 (Gpx4), a major regulator of ferroptosis (15), and upregulation of a critical oxPE death signal generator, 15-lipoxygenase-2 (15-LOX-2) (16).