Prostaglandin E2 (PGE2; Item No. 14010) activates four E prostanoid (EP) receptors, EP1-4. EP4 is a G protein-coupled receptor that, by elevating the second messenger cAMP, plays important roles in bone formation and resorption, cancer, and atherosclerosis.{16772,16773,16619} CAY10684 is a lactam that acts as a potent EP4 agonist, triggering cAMP signaling with an EC50 value of 0.8 nM.{13508} It displays more than 1,000-fold selectivity for EP4 over other EP receptors.{13508}