siRNA抑制SK-BR-3细胞株Her2/neu的表达及细胞增殖

siRNA INHIBITS Her2/neu EXPRESSION AND CELL PROLIFERATION IN SK-BR-3 CELL LINE

目的研究siRNA(smallinterferingRNA)对乳腺癌SK-BR-3细胞株Her2/neu基因表达的抑制作用,为RNAi技术在肿瘤生物治疗中的应用提供实验基础。方法体外合成两条针对Her2/neu基因的siRNA,转染SK-BR-3细胞株;分别应用逆转录聚合酶连反应(RT-PCR)法和流式细胞仪测定Her2/neu基因和蛋白的表达,并用MTT比色法测定细胞的增殖活性,AnnexinV检测细胞凋亡。结果两条siRNA分别使Her2/neu基因表达降低了42·88%、49·27%,蛋白表达降低了25·03%、56·59%。同时转染siRNA后细胞生长受到抑制,并发生细胞凋亡,凋亡率分别为28·51%、42·81%。结论siRNA可以有效抑制SK-BR-3细胞株中Her2/neu的表达,从而抑制细胞生长,并导致细胞凋亡。

Objective Using siRNA to downregulate Her2 expression in Her2 positive breast cancer cell line SK-BR-3, to observe the influence of siRNA of cell proliferation and apoptosis, Methods Two siRNAs against the Her2 gene were designed and transfected into SK-BR-3 cells respectively, Her2 gene expression was measured using RT-PCR, Her2 protein expression was analysed using flow cytometer. Cell proliferation was measured with MTI＇ assay, the apoptotic cells were stained with annexin-V-FITC and analysed by flow cytometry. Results 42.88% ,49.27% silencing of Her2 mRNA expression were observed after transfecting with two siRNA respectively. The corresponding decrease of Her2 protein expression was confirmed by flow cytometric analysis. As a consequence, cell growth inhibition was observed,28.51% and 42.81% of cells apoptosis were observed after transfecting with two siRNA respectively. Conclusion These results demonstrated that siRNA against Her2 could effectively downregulate Her2 expression in SK-BR-3 cell line, inhibit cell growth and induce cell apoptosis.