Prostaglandin E-Major Urinary Metabolite as a Biomarker for Inflammation in Ulcerative Colitis: Prostaglandins Revisited.

With the development of new therapeutic approaches, the ultimate goal of ulcerative colitis (UC) treatment is not only clinical remission but also mucosal healing. Successful mucosal healing has been associated with a dramatic risk reduction in UC recurrence and colitis-associated cancer development, which are the most critical complications of UC. However, invasive tests such as colonoscopy and biopsy are required to evaluate mucosal healing. Therefore, frequent examinations are unsuitable for UC patients. Mucosal inflammation of the colon and prostaglandin E2 production are assumed to be correlated; therefore, we considered that prostaglandin E-major urinary metabolite (PGE-MUM; 7-hydroxy-5,11-diketotetranor-prosta-1,16-dioic acid) may be a surrogate biomarker of UC activity. In this review, we propose that PGE-MUM levels reflect the colonoscopic and histological appearance of UC, suggesting that it is a more sensitive biomarker than those previously utilized for UC-related mucosal inflammation. According to the 'organ-specific chronic inflammation-carcinoma sequence' theory, by measuring PGE-MUM periodically, it would be possible to control inflammation, with subsequent prevention of UC recurrence and colitis-associated cancer development. The measurement of urine samples for PGE-MUM - a simple, noninvasive method - can reduce the patient burden as well as medical costs, suggesting its potential for application in routine practice.