Background and purpose:Urothelial carcinoma of the bladder (UCB) is the most common cancer in urinary system. Yes associated protein (YAP) gene is closely associated with urothelial carcinoma of the bladder. The study was aimed to explore the effect of siRNA targeting the YAP gene on cell proliferation and migration of T24 cells. Methods:Small interfering RNA (siRNA) was transfected together with LipofectamineTM2000 in T24 human bladder cancer cells to block the YAP signal pathway. The effect of siRNA on cell proliferation and invasiveness was assessed by cell counting kit-8 (CCK-8) assay, Transwell migration assay and wound healing assay. Quantitative real time-Polymerase chain reaction (qRT-PCR) and Western blot analysis were used to conifrm the successful suppression of YAP gene and protein by siRNA. Results:Expression of YAP gene and protein was successfully suppressed after transfected with siRNA which verified by qRT-PCR and Western blot(RNA:F=93.91, P<0.000 1; Protein: F=4.62, P<0.05). As CCK-8 test showed, the proliferation of T24 bladder cancer cells was successfully restrained by inhibition of YAP gene compared with blank control and negative control(12 h: F=6.00, P=0.037;24 h: F=41.72, P=0.000 3;36 h:F=462.8, P<0.000 1;48 h:F=236.6, P<0.000 1;72 h:F=140.5, P<0.000 1). Transwell and wound healing test were performed after YAP gene was interfered by siRNA. The result demonstrated that migration of T24 bladder cancer cells was signiifcantly inhibited (Transwell: F=43.55, P<0.05;Wound healing: F=43.55, P<0.05). Conclusion:This study suggested that YAP gene was an important enhancer for the proliferation and migration of bladder cancer cells.