The expression of costimulatory molecule PD-L1 in transitional cell carcinoma of the bladderand its clinical significance

Objective:To investigate the expression of ligand 1 of programmed death-1in human bladder transitional cell carcinoma(BTCC) and the relationship between their expression and the clinicopathological features.Methods:Immnunohistochemical staining was used to detect the expression of PD-L1 in 59 cases of BTCC tissues and 10 cases of normal bladder tissues. RT-PCR was used to investigate the mRNA expression of PD-L1 gene in 30 BTCC samples and 10 cases of normal bladder tissues.Results:There was no significant expression of PD-L1 in normal bladder tissues, but in case of tissues of bladder transitional cell carcinoma, the expression rate of PD-L1 protein and PD-L1mRNA were 62.7%(37/59) and 66.6%(20/30) respectively. The expression of PD-L1 was significantly correlated with TNM stage and lymphatic metastasis (P0.05), but not age、sex and differentiation (P0.05).Conclusions:PD-L1 is overexpressed in bladder transitional cell carcinoma, PD-L1 maybe plays certain role in carcinogenesis and progression of bladder cancer and turn into a new target of immunotherapy of bladder cancer.