pEGFPN1-dnEGFR对胃癌细胞的放疗增敏作用

The sensitivty effects of pEGFPN1-dnEGFR to radiotherapy in gastric carcinoma cells

目的探讨人表皮生长因子(EGFR)显性负性突变体真核表达载体(pEGFPN1-dnEGFR)对胃癌细胞放疗敏感性的影响。方法用pEGFPN1-dnEGFR转染人胃癌细胞株SGC-7901和NCI-N87并联合放疗,将两种胃癌细胞分别分为3组,即未处理组、pEGFP-N1空载体质粒转染组(空质粒组)、pEGFPN1-dnEGFR质粒转染组(目的质粒组),用MTT法测定对两种胃癌细胞增殖效应的影响,RT-PCR检测细胞中Bax、Cyclin D1的mRNA表达情况,Western blot检测细胞中Bax、Cyclin D1蛋白表达情况。结果两种胃癌细胞目的质粒转染组的抑制率较空质粒组和未处理组显著提高(P<0.05)。RT-PCR显示两种胃癌细胞目的质粒组Bax mRNA相对表达强度较空质粒组和未处理组升高;目的质粒组Cyclin D1mRNA相对表达强度较空质粒组和未处理组降低(P<0.05)。Western blot显示两种胃癌细胞目的质粒组Bax蛋白表达相对强度较空质粒组和未处理组明显升高;目的质粒组Cyclin D1蛋白表达相对表达强度分别较空质粒组和未处理组降低(P<0.05)。结论 pEGFPN1-dnEGFR能够提高胃癌细胞对放疗的敏感性。

Objective To explore the radio sensitivity effects on gastric cancer cells by pEGFPN1. Methods The gastric cancer cells were divided int 3 groups, including untreated group, pEGFP-N1 non-plasmid-mediated group, pEGFPNI-dnEGFR plasmid transfection group（objective plasmid group）. The proliferation of human gastric carcinoma cells, SGC-7901 and NCI-N87, which were transfected pEGFPN1-dnEGFR and conducted radiation treatment, was determinded by MTT assay. The mRNA expressions of Bax and Cyclin D1 were detected by reverse transcription PCR（RT-PCR）. Protein expressions of Bax and Cyclin D1 in cells were detected by Western blot. Results The value of inhibition（VI） of objective plasmid groups reduced significantly compared with the other groups（P〈0.05）. RT-PCR results showed that Bax mRNA relative expression in objective plasmid groups increased com- pared with the other groups,and Cyclin D1 mRNA relative expression in objective plasmid groups reduced compared with the other groups（P〈0.05）. Western blot results showed that Bax protein relative expression in objective plasmid groups increased compared with the other groups, and Cyclin D1 protein relative expression in objective plasmid groups reduced compared with the other groups（P〈0.05）. Conclusion pEGFPNI-dnEGFR could improve radiotherapy sensitivity of gastric carcinoma cells.