中文摘要：

目的探讨下调miR-221对U87胶质瘤细胞生长的影响及可能的作用机制。方法构建靶向miR-221的siRNA慢病毒表达载体并感染U87胶质瘤细胞，应用原位杂交、定量PCR和Westernblot法检测干扰后细胞内miR-221及p27蛋白表达变化，M1Tr法检测细胞增殖，流式细胞仪检测细胞凋亡及周期变化，Transwell法检测细胞侵袭力改变。结果成功构建了靶向miR-221的siRNA慢病毒表达载体，该载体能有效抑制内源性miR-221的表达，同时上调p27蛋白的表达，同时抑制细胞生长，诱导凋亡，降低细胞的侵袭力。结论成功构建靶向miR-221的RNAi慢病毒表达载体，该载体能够有效抑制miR-221的表达并抑制U87胶质瘤细胞的生长，为以miR-221为靶点的胶质瘤基因治疗的后续研究奠定基础。

英文摘要：

Objective To study the effect of knockdown miR -221 on U87 glioma cells in vitro. Method A hairpin structure of siRNA transcript templates targeting pre -miR -221 and a negative control were synthesized and ligated with lentiviral vector and all the vectors were sequenced. The recombinant lentiviral vectors were used to infect U87 cells. Then Q - PCR, western blot, MTT, FCM and transwell were used to detect the effects of knockdown miR - 221. Results The data of sequencing showed that the recombinant lentiviral vectors contained correct sequences of designed transcript templates. The results indicated that the expression of miR - 221 was inhibited, and at the same time the expression of p27 was upgraded, which was a target of miR- 221. Knockdown of miR- 221 also inhibited the growth and invasiveness of U87 and induced apoptosis in U87 cell. Conclusions An anti -miR- 221 expression siRNA lentiviral vector was constructed successfully, which could inhibit U87 glioma cell proliferation and induce cell apoptosis, and could be used to suppress target gene for further study in tumor biology.