槐糖脂通过线粒体途径诱导人胃癌SGC-7901细胞凋亡的机制

Mechanism of apoptosis of human gastric cancer cell line SGC-7901 induced by sophorolipid through mitochondrial pathway

目的探讨槐糖脂抑制人胃癌SGC-7901细胞增殖的作用,并阐明其诱导SGC-7901细胞线粒体凋亡的机制。方法不同浓度(40,80,160,320μg/ml)槐糖脂作用于人胃癌SGC-7901细胞,与未加槐糖脂处理的空白对照组进行比较,观察各浓度槐糖脂作用组中人胃癌SGC-7901细胞的变化。倒置显微镜观察槐糖脂作用后细胞活力变化,并采用CCK-8法检测各浓度槐糖脂作用后细胞的存活率; DAPI染色,荧光显微镜观察槐糖脂作用后细胞形态变化;罗丹明123(Rhodamine 123)染色,流式细胞术检测槐糖脂作用组及未加槐糖脂处理的空白对照组细胞内线粒体膜电位水平;采用Western blot检测各组Bcl-2、Bax、Cyt-C、Caspase 3及Caspase 9蛋白表达水平。结果与空白对照组比较,槐糖脂作用组人胃癌SGC-7901细胞活力下降,细胞存活率显著降低(P <0. 05),且降低程度与槐糖脂剂量成正相关,细胞形态呈现明显的凋亡样改变;与空白对照组比较,槐糖脂作用组人胃癌SGC-7901细胞线粒体膜电位显著降低(P <0. 05),Bax蛋白的表达量明显增加(P <0. 05),Bcl-2蛋白表达显著降低(P <0. 05),Cyt-C、Caspase 3及Caspase 9蛋白水平显著升高(P <0. 05)。结论槐糖脂能够抑制人胃癌SGC-7901细胞的增殖,其机制可能是通过线粒体凋亡途径诱导细胞发生凋亡。

Objective To investigate the inhibitory effect of sophorolipid on the proliferation of human gastric cancer cell line SGC-7901 and to elucidate the mechanism of mitochondrial apoptosis of SGC-7901 induced by sophorolipid. Methods Human gastric cancer cell line SGC-7901 was treated with different concentrations of sophorolipid(40, 80, 160, 320 μg/ml), and human gastric cancer cell line SGC-7901 without sophorolipid treatmen was chosen as blank control group. Changes of SGC-7901 in each sophorolipid group were observed. Changes of cell activity was observed under inverted microscope after sophorolipid treatment, and the survival rate of SGC-7901 was detected by CCK-8 method. DAPI staining was used to observe the changes of cell morphology after sophorolipid treatment under fluorescence microscope. Rhodamine 123 staining was used to detect mitochondrial membrane potential levels in each group by flow cytometry. The expression levels of Bcl-2, Bax, Cyt-C, Caspase 3 and Caspase 9 in each group were detected by Western blot method. Results Compared with blank control group, the activity of human gastric cancer cell line SGC-7901 decreased in sophorolipid groups, the survival rate of SGC-7901 decreased significantly( P <0.05), and the decrease was positively correlated with the dose of sophorolipid, and the morphology showed obvious apoptosis-like changes. Compared with blank control group, the mitochondrial membrane potential levels of SGC-7901 decreased significantly in sophorolipid groups( P <0.05), the expression of Bax protein increased significantly( P <0.05), the expression of Bcl-2 protein decreased significantly( P <0.05), and the levels of Cyt-C, Caspase 3 and Caspase 9 increased significantly( P <0.05). Conclusion Sophorolipid can inhibit the proliferation of human gastric cancer cell line SGC-7901, and the mechanism may be related to the apoptosis of SGC-7901 induced through mitochondrial apoptosis pathway.