中文摘要：

目的：检测RNA结合蛋白QKI-5在乳腺癌细胞中的表达水平以及对癌细胞增殖能力的抑制作用.方法：通过免疫印迹实验检测QKI-5在不同乳腺癌细胞株中的表达水平,通过慢病毒感染构建能够稳定过表达QKI-5基因的细胞株,使用MTT,流式细胞仪检测细胞周期来观察过表达QKI-5对细胞增殖能力及周期的影响.结果：MCF-7细胞在三株乳腺癌细胞中QKI-5表达水平相对最低,MTT实验结果显示与对照相比,过表达QKI-5的MCF-7细胞增殖能力出现显著降低P〈0.05,同时细胞周期检测显示过表达QKI-5的MCF-7细胞组出现了明显的G1期阻滞,进入S期G2/M期细胞减少.结论：在乳腺癌中QKI-5的高表达可能通过抑制癌细胞周期致使细胞增殖变缓,从而导致肿瘤生长受限.

英文摘要：

Objective：To check RNA binding protein QKI-5＇s expression level in breast cancer cells and inhibiting effect on cancer cell proliferation.Methods：QKI-5＇s expression level was checked in different breast cancer cells by Western blotting,cancer cells of overexpressed QKI-5 gene could be stabilized by slow virus infection construction,MTT and FCM were used to check cell period to express QKI-5＇s influence on cell proliferation and period.Results：MCF-7 cells have relatively low QKI-5 expression level in three breast cancer cells,MTT experiment result has obvious reduced influence on QKI-5＇s expression of MCF-7 cell proliferation P〈0.05,mean-while,cell period inspection shows that overexpressed QKI-5＇s MCF-7 cells have obvious G1 retardant,cells in S and G2/M periods are reduced.Conclusion：High expression of QKI-5＇in breast cancer could cause slow cell proliferation by inhibiting cancer cell period,hence causing limited tumor growth.