Background: Transitional Cell Carcinoma (TCC) is the most common type of urinary bladder cancer. Cyclooxygenase-2 (COX-2), a key enzyme in prostaglandins biosynthesis, has been introduced as a new candidate for targeted therapy in this cancer. In this study, we investigated the expression of COX-2 in urinary bladder TCCs and its relationship with clinicopathological parameters such as tumor gra...