Abstract: Objective: To detect the expressions of urea transporter B (UT-B) in tumor tissue of bladder cancer patients and normal urothelium tissue, and to investigate its clinical significance of expression in bladder cancer tissue.Methods: Fifty-two paraffin-embedded specimens of bladder cancer patients and 15 normal urothelium specimens were selected. The expression levels of UT-B protein were detected by immunohistochemistry method.The difference of expression of UT-B in bladder cancer tissue and normal urothelium tissue and its relationship with the clinicopathological parameters were analyzed.Results: The expression rate of UT-B protein in bladder cancer tissue was 44.2%, while it was significantly higher in control group (93.3%), and the difference between two groups was significant (P=0.001). The positive expression rates of UT-B in bladder cancer tissue were significantly decreased with the increasing of histological grades, and there were significant differences between different grade groups (P=0.010). The positive expression rate of UT-B in muscle-invasive stage (Ta+T1) was significantly lower than that in non-muscle-invasive stage (T2+T3) (P=0.014).Conclusion: The reduction or lack of UT-B expression may promote the incidence, progression and invasiveness of bladder cancer.

Key words: immunohistochemistry, urea transporter B, bladder neoplasms