Expression of CXCR7 protein in human bladder cancer and its clinical significance

Objective To explore the expression of CXCR7 in bladder cancer and analyze its clinical significance and relationship with bladder cancer recurrence. Methods The expressions of CXCR7 protein in 148 specimens of bladder cancer and 30 specimens of normal bladder tissues were detected by immunohistoehemical staining and its clinical significance was then analyzed. Results The expression of CXCR7 protein was higher in bladder cancers than in the adjacent normal tissues （P〈0.01）. CXCR7 protein expression rates were 49.4% and 71.2% in mutifoeal tumors and unifoeal tumors, while 34.0%, 65.8% and 78.6% in G1 , G2, and G3 tumors, respectively （P〈0. 01）. Expression of CXCR7 protein was higher in muscle invasive bladder cancers than in non-muscle invasive bladder cancers （72.7% versus 51.9% ,P〈0. 05）. In patients followed up for 2--95 months, CXCR7 protein expression was significantly higher in patients with recurrence than with non-recurrence （64.1 % versus 32.5%, P〈0.01）. Kaplan-Meier analysis and the log-rank test showed that the recurrence-free survival was significantly different between the group of lower CXCR7 expression group and the higher expression group （P〈0.01）. Conclusions The expression of CXCR7 protein is high in bladder cancer and the analysis of CXCR7 protein expression is potentially valuable in prognostic evaluation of bladder cancers, CXCR7 may play a role in the development of bladder urothelial cellcancer. Key words: Urinary bladder neoplasms;  CXCR7;  Immunohistochemistry;  Recurrence