Abstract:Objective: To construct an eukaryotic expression vector that contains Smac gene, which is regulated by human Uroplakin Ib (UpIb) prommer. Methods: For the directionality of Smac expression in the transitional cell carcinoma of bladder, internal CMV and T7 promoter sequences in eukaryotic expression vector pcDNA3.1-Smac were replaced with UpIb promoter to consstuct a new plasmid. The plasmid DNA was identified by gel electrophoresis after being double digested at respective sites,and then the sequence was analyzed. The expression of Smac mRTA and protein in BIU87 cell line were detected after the transfection by using the newly constructed vector. Results: The Smac gene-carrying and UpIb promoter-regulated eukaryotic expression vector pcDNA3-UpIb-promoter-Smac was successfully constructed. The expression of Smac mRNA was approximately increased by 2.1 times and the expression of Smac protein was increased in about 71﹪ BIU87 cells. Conclusion: The new vector can be effectively expressed in bladder cancer cells and be of great significance for bladder cancer-targeted genc therapy.