c-SRC基因敲减降低宫颈癌HeLa细胞活性及磷酸化的信号转导与转录激活子-3蛋白表达

c-SRC knockdown decreases phosphorylated STAT3 expression and viability of HeLa cells

本文旨在研究c-SRC蛋白对人宫颈癌HeLa细胞的活性及对磷酸化的信号转导与转录激活子-3(phosphorylated signal transducer and activator of transcription-3,p-STAT3)表达的影响。人宫颈癌HeLa细胞转染c-SRC RNA干涉质粒后,分别用RT-PCR和Westernblot检测细胞内c-SRC mRNA和蛋白的表达;用MTT比色法观察c-SRC敲减后细胞的活性;用流式细胞仪检测细胞周期;同时检测细胞内p-STAT3的表达情况。转染c-SRC RNA干涉质粒后,HeLa细胞内c-SRC mRNA和蛋白的表达显著降低;在转染c-SRC RNA干涉质粒24、48、72及96h后,细胞活性分别下降了23.1%、29.3%、38.6%和45.0%(均P<0.05)。转染c-SRC RNA干涉质粒24、48、72及96h后,HeLa细胞S期细胞数分别下降了5.6%、10.0%、15.2%和19.9%(均P<0.05)。敲减c-SRC后,细胞内p-STAT3的含量也显著下降。与对照组相比,STAT3抑制剂Piceatannol处理细胞24、48、72、96h后,细胞活性分别下降了23.8%、29.7%、37.3%和45.4%(均P<0.05),而Piceatannol预处理细胞后再用重组人c-SRC蛋白处理增加细胞内c-SRC蛋白的含量,细胞活性未见明显增加。以上结果表明,c-SRC敲减后抑制HeLa细胞的活性可能与其抑制STAT3蛋白磷酸化相关。

The present study was to determine the effect of c-SRC on the viability of human cervical cancer HeLa cells and the expression of phosphorylated signal transducer and activator of transcription-3 （p-STAT3） of the cell. Post-transfection of c-SRC RNA interference vector, RT-PCR and Western blot were utilized to observe the contents of c-SRC mRNA and protein, respectively, in HeLa cells. The MTT was used to observe the viability of the cells. Cell cycle was observed by flow cytometry. The content of p-STAT3 in the cells was also investigated after knockdown of c-SRC. Knockdown of c-SRC significantly decreased the contents of c-SRC mRNA and protein in the cells. The viability of the cells decreased by 23.1%, 29.3%, 38.6% and 45.0% （all P 0.05）, respectively, after the cells were transfected with c-SRC RNA interference vector for 24, 48, 72, and 96 h. The number of S-phase cells decreased by 5.6%, 10.0%, 15.2% and 19.9% （all P 0.05）, respectively, after transfection of c-SRC RNA interference vector for 24, 48, 72, and 96 h. The content of p-STAT3 also decreased when c-SRC was knockdowned. Compared with the control group, after treatment of HeLa cells with STAT3 inhibitor Piceatannol for 24, 48, 72, and 96 h, the cell viability decreased by 23.8%, 29.7%, 37.3% and 45.4% （all P 0.05）, respectively, while increase of c-SRC content could not reverse the inhibitory effect. These results suggest that the inhibited viability of HeLa cells caused by knockdown of c-SRC is associated with the decreased content of p-STAT3 protein.