15-Ketoprostaglandin E2 (15-keto PGE2) is a metabolite of prostaglandin E2 (PGE2) with reduced biological activity, which then by the action of prostaglandin reductase 2 (PTGR2) transforms into 13,14-dihydro-15-keto-PGE2, s a secondary metabolite without biological activity. Some experiments have shown that exists the therapeutic potential by targeting PTGR2/15-keto-PGE2 in pancreatic cancer. Besides, it is known, that 15-keto-PGE2 has higher affinity to the prostaglandin EP2 receptor than to the EP4 receptor. Some experiments also have revealed the key signaling cascade: 15-Hydroxyprostaglandin dehydrogenase (15-PGDH)/15-keto-PGE2-mediated activation of PPARγ and p21(WAF1/Cip1) in the regulation of the hepatocarcinogenesis and tumor progression.