Cyclooxygenase-2: a possible target in schistosoma-associated bladder cancer

Objective To analyse and compare the expression of cyclooxygenase (COX) enzymes in schistosoma-associated bladder cancer, and to determine any association with tumour grade or stage. Materials and methods Sixty paired samples of tumour and adjacent nonmalignant urothelium were identified. There were 25 squamous and 28 transitional cell carcinomas, and seven adenocarcinomas. Serial sections were obtained and a standard three-layer immunohistochemistry protocol, using COX-1- and COX-2-specific mouse monoclonal antibodies, applied. Results COX-1 was expressed mostly in nonvascular smooth muscle with weak reactivity in malignant and nonmalignant urothelium. Nonmalignant urothelium expressed COX-2 weakly, notably in areas of dysplasia and squamous metaplasia whereas there was a significant increase in COX-2 (P