AF and NP cells in a simulated oxidative stress environment demonstrated an upregulation of prostaglandin endoperoxidase synthase 2 (PTGS2) and downregulated glutathione peroxidase 4 (GPX4) and ferritin heavy chain (FTH), suggesting ferroptosis in the degenerated IVD [90]. The gene discussed is PTGS2; the disease is atrial fibrillation.