Expression of Cyclooxygenase-2 in Human Transitional Cell Carcinoma of the Urinary Bladder

Jang, Hoon; Kim, Wun Jae; Lee, Hyung Lae

Abstract

PURPOSE: Recent studies have supported the important role of cyclooxygenase-2 (COX-2) in various cancers derived from epithelial cell, such as the gastrointestinal tract, breast, head, and neck. In this case-control study, the clinical significance of COX-2 expression was investigated in patients with transitional cell carcinoma (TCC) of the urinary bladder.
MATERIALS AND METHODS
Tumor samples were obtained from 43 bladders of TCC patients undergoing either transurethral resection (TUR) or radical cystectomy. Normal bladder tissues were also acquired from 50 age- and sex-matched patients without bladder cancer, mainly in benign prostatic hyperplasia. Paraffin sections were assessed with immunohistochemistry using the anti-human COX-2 monoclonal antibody. COX-2 expression was graded on a scale of 0-3+ according to the intensity and rate of immunohistochemical staining.
RESULTS
COX-2 was expressed in 42 of 43 (97.7%) in human TCCs of the urinary bladder but not in all normal bladder tissues (p<0.001). COX-2 expression was significantly higher in invasive tumors than in superficial TCCs (p=0.038). Additionally, COX-2 expression had a significant correlation with the tumor stage (p=0.016), but not with the tumor grade (p=0.169).
CONCLUSIONS
This study showed that COX-2 was expressed in human TCCs of the urinary bladder, and its expression was highly correlated to the tumor stage. These results support the possibility that COX-2 might play an important role in tumorigenesis and invasiveness of human TCCs of the urinary bladder.