小干扰RNA诱导人卵巢癌细胞MDR1基因沉默的研究

目的 采用RNA干扰技术逆转人卵巢癌OVCAR8/TR细胞中多药耐药基因,探讨该技术能否有效地抑制多药耐药基因MDR1的表达,降低该基因编码的糖蛋白P-gp的水平.方法 设计合成针对MDR1的小片段RNA(siRNA),将合成的siRNA用脂质体转染具有多药耐药基因MDR1高表达的人卵巢癌泰素耐药细胞株OVCAR8/TR,用荧光定量RT-PCR检测转染后不同时间点MDR1的mRNA的变化,流式细胞仪定量测定转染后不同时间点P-gp表达的情况.结果 MDR1的siRNA转染细胞48 h基因的抑制达最高,转染的第5 d回到正常水平.阴性对照组mRNA的量与未转染组的mRNA的量差异无统计学意义.P-gp在转染后的72 h其抑制最强,至第5 d时恢复接近正常水平,阴性对照组蛋白表达与未转染组的蛋白表达差异无统计学意义.结论 siRNA能够有效地抑制多药耐药基因MDR1的mRNA和P-gp的表达,为逆转卵巢癌的多药耐药带来了新的希望.

Research on Human Ovarian Cancer Cell MDR1 Gene Silenced by siRNA

Objective To evaluate the effects of siRNA on the inhibitions of mRNA and P-gp expression of ovarian cancer cell with high expression of multidrug resistance gene(MDR1).Methods The siRNA was transferred into ovarian cancer cell line OVCAR8/TR.The real time RT-PCR and flow cytometry were used respectively to determine the expression of mRNA or P-gp of MDR1.Results The inhibition of mRNA-84% expression occurred at 48 h after cell transfection,and the inhibition of P-gp-85.23% expression occurred at 72 h after cell transfection.Afterward the inhibitions to mRNA and P-gp expressions gradually returned to the normal levels.The amounts of mRNA and P-gp expression had no difference between negative control and untransfected cells.Conclusion RNA interference presents in the human ovarian cancer cell,siRNA can effectively inhibit the expression of mRNA and P-gp of MDR1.The RNAi may represent a new approach for the treatment of MDR1-mediated drug resistance.