RNA干扰抑制裸鼠皮下移植瘤中Livin基因表达的实验研究

Experimental research on RNA interference targeting Livin in treatment of gastric carcinoma in nude mice

目的:利用RNA干扰(RNA interference,RNAi)技术在裸鼠皮下移植瘤中抑制Livin基因表达,探讨RNA干扰用于胃癌治疗的可行性。方法:SGC-7901细胞注射人裸鼠皮下,建立裸鼠皮下移植瘤的模型,设计靶向Livin基因的小干扰RNA(Small interference RNA,siRNA),构建重组表达质粒pTZU6+1-siRNA-Livin,并导入裸鼠皮下移植瘤中,在体内诱导RNAi,采用RT-PCR和免疫化学检测Livin基因表达,Western blot检测Bax和Bcl-2改变。结果:重组质粒pTZU6+1-siRNA-Livin导入裸鼠皮下移植瘤后14d瘤体体积明显减小,Livin的mRNA和蛋白表达均明显下调。结论:RNA干扰明显抑制了靶基因Livin的表达及肿瘤细胞生长,可能与上调Bax的表达、下调Bcl-2,从而诱导肿瘤细胞凋亡有关。

Objective： To investigate the feasibility of gastric carcinoma gene therapy by utilizing RNA interference （RNAi） to inhibit the expression of Livin in vivo. Methods：SGC-7901was injected into nude mice to form hypodermical gastric carcinoma.Small interference RNA（siRNA） homologous to Livin gene were designed, pTZU6＋1-siRNA-Livin vector was constructed and injected into tumor to induce RNAi.The changes of Livin gene expression were detected with RT-PCR and immunochemistry,the expression of Bax and Bcl-2 were detected by western blot. Results： 14 days after transfeeted with pTZU6＋1-siRNA-Livin,both the mRNA and the protein of Livin decreased obviously. The level of Bax was up-regulated and the level of Bcl-2 was decreased. Conclusion： RNA interference targeting Livin inhibits Livin expression and tumor growth, which may be related to up-regulation of Bax and down-regulation of Bcl-2.