雷公藤内酯酮下调SOX2表达抑制肺癌细胞恶性行为的研究

Inhibitory effect of triptonide on the malignant behaviors of lung cancer cells by down-regulation of SOX2 expression

目的:研究雷公藤内酯酮能否抑制肺癌细胞中关键促癌因子SOX2的表达。方法:用不同剂量的雷公藤内酯酮(0.025μg/ml、0.05μg/ml、0.1μg/ml和0.2μg/ml)作用于常规培养的SK-MES-1人肺癌细胞。用荧光定量PCR检测SK-MES-1细胞中SOX2 mRNA表达水平的变化。用Western-blot检测SK-MES-1细胞中SOX2蛋白表达水平的变化。用亚硫酸氢盐测序检测SKMES-1细胞中SOX2基因启动子区DNA甲基化水平的变化。用CCK-8实验、Transwell实验和悬浮成球实验分别检测SK-MES-1细胞增殖能力、侵袭能力和肿瘤干细胞亚群自我更新能力的变化。结果:0.05μg/ml、0.1μg/ml和0.2μg/ml的雷公藤内酯酮下调了SK-MES-1细胞中SOX2 mRNA和SOX2蛋白的表达水平,升高了SOX2基因启动子区的DNA甲基化水平,抑制了SK-MES-1细胞的增殖能力、侵袭能力和肿瘤干细胞亚群的自我更新能力。结论:雷公藤内酯酮通过表观遗传调节机制下调了肺癌细胞中关键促癌因子SOX2的表达,从而抑制了肺癌细胞的恶性行为。

Objective： To investigate whether triptonide can inhibit the expression of the key oncogenic factor SOX2 in lung cancer cells. Methods：In vitro cultured SK-MES-1 human lung cancer cells were treated with 0. 025 μg/ml,0. 05 μg/ml,0. 1 μg/ml and 0. 2 μg/ml triptonide.Expressions of SOX2 mRNA and protein in SK-MES-1 cells were detected by real time PCR and Western-blot,respectively. The DNA methylation level at SOX2 promoter region in SK-MES-1 cells was measured by bisulfite sequencing. The proliferation,invasion and self-renewal capacities of SK-MES-1 cells were determined by CCK-8,transwell and sphere formation assays. Results： 0. 05 μg/ml,0. 1 μg/ml and 0.2 μg/ml triptonide decreased mRNA and protein expression levels of SOX2 in SK-MES-1 cells,and increased the DNA methylation level at the SOX2 promoter region. Moreover,triptonide effectively inhibited the proliferation,invasion and tumor stem cell self-renewal capacities of SK-MES-1 cells. Conclusion： Triptonide can inhibit the malignant behaviors of lung cancer cells by down-regulating the expression of the key oncogenic factor SOX2 through an epigenetic regulation mechanism,thus showing a great value in lung cancer treatment.