鼻咽癌CNE-2细胞株胰岛素样生长因子-1受体和表皮生长因子受体沉默的放疗增敏机理

Dual Silencing of Insulin-Like Growth Factor-1 and Epidermal Growth Factor Receptors to Induce the Radioactivity of Nasopharyngeal Cancer Cells

目的:评价RNA干扰(RNAi)同时沉默胰岛素样生长因子-1受体(IGF-1R)和表皮生长因子受体(EG-FR)后生物学特性变化及对鼻咽癌CNE2细胞株放疗敏感性的改变。方法:构建荧光标记的靶向IGF-1R及EGFR信使RNA真核表达质粒,质粒转染鼻咽癌CNE2细胞株,共聚焦显微镜观察细胞转染结果,行平板克隆实验检测细胞存活分数;流式细胞术检测细胞凋亡及细胞周期;Western-blot法检测细胞周期相关蛋白cdk4/6,cyclin D1和c-myc。结果:成功构建真核表达质粒;siRNA-IGF-1R和EGFR组的细胞存活分数显著降低(P<0.05),与对照组相比,凋亡率显著增高(P<0.05),G0/G1期细胞比例明显增多,而S期和G2/M期细胞比例明显减少,细胞周期相关蛋白cdk4/6,cyclin D1和c-myc蛋白表达降低(P<0.05)。结论:RNA同时干扰沉默IGF-1R和EGFR可以引起鼻咽癌细胞周期蛋白表达降低,细胞周期阻滞,促进细胞凋亡。

Objective： To study the effect of RNA interference of insulin-like growth factor-1（IGF-1） and epidermal growth factor（EGF） receptors on biological features and radioactivity of NPC cells.Methods： The IGF-1R and EGFR target RNAi eukaryotic expression plasmids labeled with fluorescence and transfect the nasopharyngeal cells（CNE-2） were constructed.The transfection efficiency was tested by the laser confocal microscopy.The survival fraction was investigated by cell colony formation after irradiation.The cell cycles and apoptosis were determined via flow cytometry.The cyclins（cdk4/6,cyclin D1 and c-myc） expressions were assessed by Western blot.Results： The eukaryotic expression plasmid was successfully constructed.Compared with the control group,the siRNA-IGF-1R EGFR group showed significantly decreased survival fraction（P0.05）,increased apoptosis and G0/G1 cell ratio（P0.05）,and detreased cell ratio of S stage and G2/M.The Western-blot results showed that the cdk4/6,cyclin D1,and c-myc expression significantly decreased（P0.05）.Conclusion： The dual-silencing of IGF-1R and EGFR are capable of decreasing expression of NPC cyclins and blocking cell cycles,which can promote the apoptosis.