RNAi抑制STAT3基因表达对人宫颈癌SiHa细胞化疗敏感性的影响

Inhibition of STAT3 by RNA Interference on Sensitivity to Chemotherapy of Human Cervical Carcinoma Cell Line SiHa

目的:探讨信号转导因子与转录激活因子3(STAT3)短发夹RNA(short hairpin RNA,shRNA)真核表达载体对宫颈癌SiHa细胞化疗敏感性的作用。方法:构建STAT3基因shRNA真核表达质粒并转染宫颈癌SiHa细胞,RT-PCR及免疫蛋白印迹分别检测STAT3基因的mRNA及蛋白表达水平。细胞经不同浓度顺铂(DDP)作用后,流式细胞术(FCS)检测细胞凋亡率,四甲基偶氮唑蓝比色(MTT)法检测细胞生长抑制率并计算DDP的50%抑制浓度(IC_(50))。结果:与各对照组细胞相比,转染STAT3基因shRNA真核表达载体的SiHa细胞,STAT3基因在mRNA和蛋白水平表达均下降,凋亡率均明显增加,细胞对DDP的IC_(50)值明显下降,差异均有统计学意义。结论:针对STAT3基因的shRNA真核表达载体有效地抑制宫颈癌SiHa细胞STAT3基因表达,增强其对化疗药物DDP的敏感性。

Objective： To investigate the effects of eukaryotic vector expressing short hairpin RNA （shRNA） of signal transducers and activators of transcription 3 （ STAT3 ） on the sensitivity to chemotherapy of hmnan cervical carcinoma SiHa cells. Methods ： Vectors containing shRNA targeting STAT3 （pSTAT3-siRNA） were constructed and transfected into SiHa cells. The mRNA and protein expressions of STAT3 were determined by RT-PCR and Western blotting, respectively. The different cell groups were treated under dif- ferent density of cisplatin （DDP）. The apoptosis rate was measured by flow cytometry （FCS）. The cell viability was detected by methyl thiazolyl tetrazolium （MTF） assay and 50% inhibitive concentration （IC50） of DDP was examined also. Results： The STAT3 expression in pSTAT3-siRNA group was significantly inhibited compared with other groups. At same time, the apoptotic rate was significantly increased and the IC50 of DDP was significantly decreased than that of other groups. Conclusion： The STAT3 specific shRNA expression vector could effectively suppress the expression level of STAT3 gene in SiHa cells, and enhance their sensitivity to DDP.