虎眼万年青总皂苷诱导人乳腺癌MCF-7细胞凋亡机制研究

Study on the apoptotic mechanisms of human breast cancer MCF-7 cells induced by total saponins of Ornithogalum caudatum ait.

为探讨虎眼万年青总皂苷(OCA-TS)诱导人乳腺癌MCF-7细胞凋亡的分子机制,本研究采用溴化四氮唑蓝(MTT)法检测OCA-TS对MCF-7细胞增殖的抑制作用,并观察细胞凋亡形态、检测细胞膜电位及凋亡相关蛋白含量变化。实验表明,OCA-TS可显著抑制人乳腺癌MCF-7细胞的增殖(IC 50为93.17μg/mL),电镜下细胞呈现典型的凋亡形态;流式细胞仪检测结果显示不同浓度的OCA-TS作用MCF-7细胞48 h后,细胞内线粒体膜电位、Ca 2+浓度和Cyt-C的表达水平均无显著变化;细胞内Caspase-8和Caspase-3的活性显著升高,而Caspase-12的活性均未见显著改变,Western blot检测细胞内Fas、FasL和FADD蛋白表达水平显著升高。综上说明OCA-TS诱导MCF-7细胞凋亡的作用可能是通过启动死亡受体途径而不是通过线粒体途径和内质网途径实现的。

To investigate the molecular mechanism of apoptosis of human breast cancer MCF-7 cells induced by total saponins of Ornithogalum caudatum Ait(OCA-TS),MTT assay was used to detect the inhibitory effect of OCA-TS on the proliferation of MCF-7 cells and the changes of apoptosis morphology,membrane potential and apoptosis related protein content were observed.The results showed that OCA-TS could significantly inhibit the proliferation of human breast cancer MCF-7 cells(IC 50 was 93.17 g/mL),and the cells showed typical apoptotic morphology under electron microscopy.The results of flow cytometry showed that 48 hours after mca-7 cells were treated with different concentrations of OCA-TS,there was no significant change in mitochondrial membrane potential,Ca 2+concentration and Cyt-C expression level;the activities of Caspase-8 and Caspase-3 were significantly increased,but the activities of Caspase-12 were not significantly changed,and the expression levels of Fas,FasL and FADD protein were significantly increased by Western blot.In conclusion,the apoptosis of MCF-7 cells induced by OCA-TS may be realized by activating death receptor pathway rather than by mitochondrial pathway and endoplasmic reticulum pathway.