title: [COX-2 inhibitors in inflammatory bowel disease: friends or foes?].
abstract: The cyclooxygenase (COX) is a key enzyme in the conversion of arachidonic acid to prostaglandins. COX-1 is constitutively expressed and is a critical housekeeping gene, whereas COX-2 is rapidly upregulated by growth factors and cytokines and thus responsible for inflammation. COX-2 is frequently overexpressed in colonic adenoma and carcinoma. Specific inhibitors of COX-2 have been shown to induce apoptosis in tumor cells and to inhibit tumor growth in animal models and in humans. Long-standing IBD patients have increased risk of developing colorectal cancer compared to general population. IBD-associated colorectal carcinogenesis is probably promoted by chronic inflammation and closely related to COX-2. In a recent study, powerful chemopreventive ability of selective COX-2 inhibitor was observed in colitis-related colon carcinogenesis in mouse model. But it was reported that even selective COX inhibitors aggravated the DSS-induced colonic inflammation. It is assumed that endogenous PGs are involved in the mucosal defense against DSS-induced colonic ulcerations which are produced by COX-1 at early phase and by COX-2 at late phase. Long-term use of COX-2 inhibitors for the chemoprevention of colitic cancer is needed to define their mechanism of action, that reduce side effects and have specific tumor target.
authors.affiliation: Department of Internal Medicine, Eulji University School of Medicine, Nowon-Gu, Seoul, Korea. pys1109@eulji.ac.kr
authors.forename: Young Sook
authors.initials: YS
authors.lastname: Park
mesh_terms: D000818:Animals; D003093:Colitis, Ulcerative / Q000188:drug therapy*; D003110:Colonic Neoplasms / Q000175:diagnosis; D051545:Cyclooxygenase 1 / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000378:metabolism; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D051379:Mice; D023421:Models, Animal
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2