中文摘要：

目的研究过表达核糖核酸抑制因子（RI）对膀胱癌移植瘤侵袭转移及上皮细胞间质转化（EMT）的影响。方法将RI过表达质粒（pIRES2-EGFP-RI）和阴性对照质粒（pIRES2-EGFP）稳定转染膀胱癌T24细胞,稳定表达细胞株分别命名为：T24-RI组、T24vector组、T24组。将各组T24细胞分别接种至BALB/C裸鼠左腋皮下,观察移植瘤的生长、微血管密度及肺组织转移灶的变化;进一步分析RI、MMP-2、MMP-9、EMT相关蛋白（E-cadherin、N-cadherin、Vimentin、Snail、Slug、Twist蛋白）在肿瘤组织中的表达水平。结果 T24-RI组较T24组与T24vector组,瘤体质量显著降低（P〈0.01）,抑瘤率分别为26.67%和38.85%;与对照组比较,T24-RI组瘤组织微血管密度明显减少,肺组织未见明显转移灶,同时CD31在瘤组织中表达减少;免疫组织化学染色显示：T24-RI组瘤组织中RI、E-cadherin蛋白的表达明显升高,而MMP-2、MMP-9、N-cadherin、Vimentin、Snail、Slug、Twist蛋白表达明显降低。结论过表达RI可能通过调节侵袭转移EMT关键蛋白的表达,显著抑制了膀胱癌移植瘤生长、侵袭和转移的潜能。

英文摘要：

Objective To investigate the effect of over-expression of human ribonuclease inhibitor suppresses invasion and migration of transplanted bladder cancer.Methods The T24 cells were stably transfected with pIRES2-EGFP-RI and pIRES2-EGFP plasmid respectively.Using the cell transfected with pIRES2-EGFP and untransfected cell as controls.and the positive clones were screened by G418,respectively;Tumor cells of the three groups at 2×106 were respectively injected into the back of BALB/C nude mice to establish the xenograft models.Change of micro-blood vessels in tumor tissue and expression of CD31 were detected by Immunohisto-chemical and HE staining.Immunohisto-chemical assay was used to detect the expression of RI,MMP-2,MMP-9,Ecadherin,N-cadherin,Vimentin,Snail,Slug,Twist in the tumors.Results Animal experiment showed that the T24-RI cells group significantly inhibited the growth of bladder cancer compared with the other two control groups.Compared with the T24 and T24vector cells groups,the microvessel density in tumor tissue of T24-RI group was notably reduced and the expressions of MMP-2,MMP-9,N-cadherin,Vimentin,Snail,Slug,Twist significantly were decreased simultaneously,while the expressions of RI and Ecadherin were increased.Conclusion up-regulation RI can inhibit the growth of transplanted bladder cancer in nude mice by decreasing the expression of invasion protein and EMT protein.