To better understand the importance of chronic inflammation in bladder cancer pathogenesis and progression, we investigated COX-2 and NF-κB p65 immunohistochemical expression in a large series of normal epithelium and bladder carcinomas, and we correlated those findings with cancer cell differentiation, tumor grade and stage, and clinical-pathologic features of bladder cancer patients. Here, PTGS2 is linked to urinary bladder cancer.