siRNA沉默DNA聚合酶β基因表达对食管癌EC9706细胞放疗敏感性的影响

摘要

Objective To evaluate the effects of silencing DNA polymerase β by small interfering RNA (siRNA) on the radiotherapeutic sensitivity of human esophageal carcinoma cell line EC9706. Methods Various siRNA were transfect-ed into EC9706 cells with lipofectamine technique.Real-time PCR was performed to detect the expression levels of polβ mRNA in different groups,respectively.Three groups of cell were exposed to different doses of radiation (0,2,4,6,8 Gy).Cell survival ratio was detected by means of CCK8 method.And the detection of the apoptosis rate was completed by FCM. Results The expression of polβ mRNA and protein were surpressed obviously in the specific sequence siRNA group (P<0.01).The result of CCK8 showed that cell survival ratio was declining with the increase of radiotherapeutic dose (P<0.05).The cell apoptosis rates of silence polβ group was significantly higher than of not siRNA group and the blank control group (P<0.01),after irradiation,the cell apoptosis rate increase of silence polβ group was significantly higher than of not siRNA group and the blank control group (P<0.01). Conclusion The experiments confirm that si-lencing DNA polymeraseβby siRNA can significantly enhance the radiosensitivity of esophageal carcinoma cell.%目的探讨siRNA沉默DNA聚合酶β(polβ)基因表达对食管癌EC9706细胞放疗敏感性的影响。方法利用脂质体将siRNA转染至EC9706细胞，采用实时荧光定量PCR检测3组不同转染的细胞中polβ mRNA的表达变化；不同剂量(0、2、4、6、8 Gy)照射3组细胞，CCK8方法检测各组细胞的存活率；用3 Gy照射，流式细胞术检测每组细胞的凋亡率。结果转染沉默polβ组polβ基因表达水平显著降低(P<0.01)；CCK8检测结果显示，随着照射剂量的增加，细胞存活率呈下降趋势，其中沉默polβ组细胞存活率显著低于两个对照(P<0.05)；沉默polβ组细胞凋亡率显著高于无关siRNA组或空白对照组(P<0.01)，照射后沉默polβ组细胞的凋亡率增加量显著高于无关siRNA组和空白对照组(P<0.01)。结论沉默食管癌细胞polβ基因表达可增加其对放疗的敏感性。