中文摘要：

目的：研究Stromal antigen 2（STAG2）基因在膀胱癌中的表达,并探讨STAG2基因在膀胱癌细胞侵袭迁移及凋亡过程中的作用。方法：采用逆转录实时定量聚合酶链式反应（RT-q PCR）和蛋白印迹法（Western Blotting）分析STAG2在膀胱癌细胞表达特点;利用慢病毒技术过表达STAG2基因转染膀胱癌细胞并使用嘌呤霉素筛选稳定转染细胞株;细胞划痕实验和Transwell实验观察STAG2过表达对膀胱癌细胞迁移和侵袭功能的影响;流式细胞仪检测STAG2基因过表达对膀胱癌细胞的凋亡影响,Western Blotting检测下游分子E-cadherin、Vimentin表达水平。结果：在膀胱癌细胞系5637中STAG2表达远低于正常膀胱上皮细胞;慢病毒过表达效率达到80%以上;STAG2过表达后膀胱癌细胞划痕愈合速度变慢;穿过Transwell小室的细胞数明显变少;膀胱癌细胞凋亡数明显增加,下游分子E-cadherin表达升高、Vimentin表达下降。结论：STAG2可能是一个新的肿瘤抑制基因,在膀胱癌细胞侵袭迁移和细胞凋亡中起着重要。

英文摘要：

Objective To investigate the expression of Stromal antigen 2（STAG2） in bladder cancer and explore the role of STAG2 gene in invasion,migration and apoptosis of bladder cancer cells. Methods Reverse transcription quantitative polymerase chain reaction and Western blotting were used to analyze the expression of STAG2 in bladder cancer cells and tissues. Transfection of bladder cancer cells with overexpression of STAG2 gene by lentivirus technique and screening of stable transfected cell lines by puromycin. The effects of STAG2 overexpression on migration and invasion of bladder cancer cells were observed by cell scratch assay and Transwell assay. The effect of STAG2 overexpression on apoptosis of bladder cancer cells was detected by fl ow cytometry. Results The expression of STAG2 in bladder cancer cell line 5637 was much lower than that in normal bladder epithelium; The over-expression efficiency of lentivirus was more than 80 %; The scar healing rate of bladder cancer cells was slower after transfection; the number of cells passing through the Transwell chamber was significantly reduced but the number of apoptotic cells in bladder cancer cells was significantly increased after transfection; The expressions of E-cadherin and Vimentin were detected by Western Blotting. Conclusion STAG2 may be a novel tumor suppressor gene,which plays an important role in invasion,migration and apoptosis of bladder cancer cells.