RNA干扰抑制人结肠癌SW480细胞EGFR的表达及其对体外生长情况影响的研究

目的研究利用RNA干扰技术抑制人结肠癌SW480细胞表皮生长因子受体(EGFR)基因的表达,并观察受抑制后SW480细胞体外生长情况的改变。方法利用脂质体将siRNA转染进入SW480细胞(野生型K-ras基因表达阳性),在细胞内形成双链siRNA,识别并降解EGFR mRNA。通过荧光定量RT-PCR检测EGFR mRNA的表达水平,Western blot检测EGFR蛋白的表达,MTT法检测SW480细胞的增殖抑制情况,流式细胞学检测细胞凋亡情况。结果转染EGFR395-siRNA和EGFR1499-siRNA的SW480细胞其EGFRmRNA及蛋白表达均较对照组明显降低(P<0.05);转染EGFR395-siRNA和EGFR1499-siRNA的SW480细胞增殖率较对照组降低(P<0.05),凋亡率增高(P<0.05)。结论 siRNA能有效抑制SW480细胞EGFR基因的表达,具有抑制细胞增殖和促进细胞凋亡的作用。

Depressed EGFR Expression Induced by RNA Interference and Its Effect on Growth of Human Colonic Cancer SW480 Cells in Vitro

Objective To study the relationship between depressed epidermal growth factor receptor(EGFR) gene expression induced by RNA interference and changes of proliferation and apoptosis of human colonic cancer SW480 cells.Methods Double-stranded siRNA were constructed by liposome and siRNA in the SW480 cells,and the EGFR mRNA was recognized and degraded.The expression level of EGFR mRNA was detected by RT-PCR.The expression level of EGFR protein was detected by Western blot.The cell proliferations of SW480 cells were measured with MTT method.The cell apoptosis rate was detected with flow cytometry.Results Compared with the control group,the levels of EGFR mRNA and protein were decreased in the EGFR395-specific siRNA group and the EGFR1499-specific siRNA group(P<0.05);the cell proliferation rate was decreased,and the cell apoptosis rate was increased in the EGFR395-specific siRNA group and the EGFR1499-specific siRNA group(P<0.05).Conclusion siRNA can inhibit the expression of EGFR mRNA in SW480 cells,which leads to the inhibition of cell proliferation and the enhancement of cell apoptosis.