沉默GRP94 基因对乳腺癌MCF7 细胞增殖和凋亡的影响

目的： 研究沉默葡萄糖调节蛋白GRP94 (Glucose regulated protein，GRP94)对乳腺癌MCF7细胞增殖、凋亡的影响及潜在机制。方法：设计并化学合成靶向沉默GRP94基因的小干扰RNA，通过脂质体转染入MCF7细胞中，采用qRT-PCR和Western blot分别检测GRP94、cyclinD1、Bax和Bcl-2 mRNA和蛋白的表达水平；通过流式细胞术检测细胞凋亡比例变化，Hoechst 33258染色检测凋亡细胞核变化、CCK8实验检测细胞增殖能力的变化。结果： GRP94 siRNA组GRP94基因的表达水平被有效抑制；与对照组相比，GRP94-siRNA转染组的细胞凋亡比例明显增加；凋亡细胞核形态发生变化；增殖能力明显下降；mRNA及蛋白水平cyclinD1、Bcl-2表达明显下调，Bax表达增加。结论：沉默GRP94基因可明显抑制乳腺癌MCF7细胞增殖能力，促进细胞凋亡的发生，且其可能通过下调cyclinD1、Bcl-2和上调Bax表达参与其中。

Effect of GRP94 silencing on proliferation and apoptosis of human breast carcinoma MCF7 cells

 Objective: To determine the effects of silencing glucose regulated protein (GRP94) on the proliferation and apoptosis of breast carcinoma MCF7 cells. Methods: Chemically synthesized siRNA targeting GRP94 gene and transfected into MCF7 cells used by Liopfectamine RNAIMAX. The mRNA and protein expression levels of GRP94,cyclinD1,Bax and Bcl-2 were detected by Real-time PCR and Western blot.CCK8 assay was used to detect the effect of specific GRP94 siRNA on cell proliferation and the effect on cell cycle and apoptosis were analyzed by flow cytometry and Hoechst 33258 staining. Results:  Compared with the siRNA NC cells,the expression of GRP94 was significantly down regulated in MCF7 cells.Knockdown of GRP94 in MCF7 cells decreased cell proliferation and promoted cell apoptosis.The expression of cyclinD1and Bcl-2levels were significantly reduced,and Bax level was increased in siRNA-GRP94 MCF7 cells.Conclusion: The siRNA mediated GRP94 silence significantly inhibits MCF7 cell proliferation，promoted cell apoptosis by down regulating cyclin D1,Bcl-2 expression and up regulating the Bax expression in MCF7 cells.