PTGS2（prostaglandin-endoperoxide synthase 2），癌症关联基因，基因ID：5743，前列腺素内过氧化物合酶（PTGS），又称环加氧酶，是前列腺素生物合成中的关键酶，既是一种双加氧酶又是一种过氧化物酶。PTGS有两种同工酶：组成型PTGS1和诱导型PTGS2，它们在表达和组织分布的调节上存在差异。这个基因编码诱导同工酶。它由特定的刺激事件调节，提示它与炎症和有丝分裂发生相关的前列腺素生物合成有关。Prostaglandin-endoperoxide synthase (PTGS)， also known as cyclooxygenase， is the key enzyme in prostaglandin biosynthesis， and acts both as a dioxygenase and as a peroxidase. There are two isozymes of PTGS: a constitutive PTGS1 and an inducible PTGS2， which differ in their regulation of expression and tissue distribution. This gene encodes the inducible isozyme. It is regulated by specific stimulatory events， suggesting that it is responsible for the prostanoid biosynthesis involved in inflammation and mitogenesis.关联癌症：结直肠癌。关联化疗药物：阿司匹林。