Investigating the epigenetic alterations that impact both COX enzymes and prostanoid receptors may inform on pathological events that characterize the immunomodulatory functions of these inflammatory lipid mediators in various immune disorders and may be relevant for the efficient clinical use of NSAIDs, COX-2 selective inhibitors, and EP receptor antagonists at both preventive and therapeutic levels. The gene discussed is PTGS2; the disease is immune system disorder.