Abstract: Objective:To study the expressions of AAX14401 in the normal bladder tissueand the human bladder transitional cell carcinoma tissue, and to analyze its function in the occurrence and development of bladder cancer. Methods:Seventy-five cases of specimens of bladder transitional cell carcinoma were collected and used as experimental group and 12 cases of normal bladder mucosa specimens were selected as control group. The positive expression rates of glutathione S-transferase pi-1(GSTP1) and AAX14401 were detected by immunohistochemistry. The differences of positive expression rates of GSTP1 and AAX14401 proteins between bladder cancer tissue and normal bladder tissue were analyzed. Results:The positive expression rate of GSTP1 protein in normal bladder tissue was 58.3%, while it was 90.7% in bladder cancer tissue, and the difference between them was significant (P<0.01). The positive expression rate of AAX14401 protein in normal bladder tissue was 0%, while it was 2.7% in blandder cancer tissue, and there was no significant difference between them(P=0.596). There was no one with positive AAX14401 expression and positive GSTP1 expression in bladder cancer tissue at the same time. There were 2 cases with positive AAX14401 expression in bladder cancer tissue with negative GSTP1 expression; there was a negative correlation between the positive expressions of AAX14401 and GSTP1 proteins in bladder cancer (r=-0.274, P=0.018). Conclusion:The expression of AAX14401 protein may promote the incidence and progression of bladder cancer.

Key words: bladder neoplasms, AAX14401 protein, glutathione S-transferase P-1, immunohistochemistry, Anti-AY antibody