Experimental Study Of B7-H4Expression In Bladder Urothelial Carcinoma And Immune Escape Mechanisms

Objective：1、To investigate Expression and clinical significance of B7-H4in tissue and serum ofpatients with bladder urothelial carcinoma；2、To study the effects of activated T lymphocytes in vitro Cytotoxicity to bladdercancer BIU-87cells after closing B7-H4pathway.Methods:1、1.1The expression of B7-H4in49cases was detected by immunohistochemicalmethod, the relationship between the expression and clinical pathological parametersof bladder urothelial carcinoma was also analyzed；1.2the levels of sB7-H4in45cases together with45cases of healthy volunteerswere detected by ELISA，the relationship between the levels and clinical pathologicalparameters of bladder urothelial carcinoma was also analyzed；2、2.1The expression of B7-H4in bladder cancer BIU-87cells was detected byImmunocytochemical staining method；2.2Separation, purification and activation of T lymphocytes in vitro；2.3the effects of activated T lymphocytes in vitro Cytotoxicity to bladder cancerBIU-87cells after closing B7-H4pathway was detected by WST-8method.Results:1、1.1In normal bladder tissue, B7-H4was not detected. But in bladder urothelialcarcinoma, the positive rate of B7-H4was (24/49)49.0%, and B7-H4expression wasstrongly associated with clinical stage and pathological grade (P<0.05)；1.2Compared to healthy volunteers, the levels of sB7-H4in patients wassignificantly increased (P<0.05), and high grade patients was significantly more thanlow grades(P<0.05). 2、2.1B7-H4protein expresses on bladder cancer BIU-87cells；2.2T lymphocytes was successfully separated, purificated and activated in vitro；2.3cytotoxic activity of activated T lymphocytes against BIU-87cells wassignificantly enhanced by closed B7-H4pathway than the non-closed（P＜0.05），anddose-dependent manner.Conclusion:The high expression of B7-H4is strongly associated with neoplastic progressionand immune escape of bladder cancer. Closing B7-H4may interfere with therecurrence and progress of bladder urothelial carcinoma.