[关键词]
[摘要]
目的 探讨绞股蓝次级皂苷H (Gypensapogenin H,GH)对人乳腺癌MCF-7细胞的诱导凋亡作用。方法 采用5、10、20、40、60、80 μmol/L的GH处理人乳腺癌MCF-7细胞48 h后,MTT法测定GH对细胞增殖的影响;20 μmol/L的GH作用细胞24 h后,相差显微镜下观察细胞的形态学变化,DAPI染色,荧光显微镜下观察凋亡小体的形成;GH作用细胞6、12、24 h后,流式细胞仪测定细胞凋亡率;免疫印迹法检测GH对Bcl-2、Bax、Cytochrome C、Caspase 3等蛋白表达的影响。结果 GH抑制细胞增殖作用呈明显的浓度相关性,半数抑制浓度(IC50)为(8.67±1.22)μmol/L;GH组细胞形态与对照组比较发生显著变化,主要表现为细胞皱缩、染色质浓缩、细胞核变形;细胞经DAPI染色后在荧光显微镜下可观察到有凋亡小体形成;随GH作用时间延长,细胞凋亡率明显上升,与对照组比较,GH作用12、24 h细胞早期凋亡率显著升高(P<0.05、0.01);蛋白免疫印迹显示,与对照组比较,GH作用6、24 h Bax,6、12、24 h Cleaved Caspase 3和Cytochrome C蛋白水平显著增加(P<0.05、0.01);6、12、24 h Bcl-2和12、24 h Caspase 3蛋白表达量显著减少(P<0.05、0.01)。结论 GH通过线粒体通路诱导乳腺癌MCF-7细胞凋亡。
[Key word]
[Abstract]
Objective To investigate the cell apoptosis of human breast cancer MCF-7 cells induced by gypensapogenin H in vitro. Methods After human breast cancer MCF-7 cells were treatment with GH of 5, 10, 20, 40, 60 and 80 μmol/L for 48 h, the effect of GH on cell proliferation was measured by MTT assay. After cells were treated by GH for 24 h, the morphological changes were observed under Phase contrast microscope, and apoptotic bodys were observed under fluorescence microscope with DAPI staining. Additionally, flow cytometry was used to evaluate the apoptosis rate, Western blotting was used to detect the effect of GH treating for 6, 12, and 24 h on the expression of Bcl-2, Bax, Cytochrome c, Caspase 3 and other proteins. Results GH inhibited cell proliferation in a concentration-dependent manner, and the half inhibitory concentration (IC50) was (8.67±1.22) umol/L. Compared with control group, the cell morphology of GH group changed significantly, mainly in cell shrinkage, chromatin concentration and nuclear deformation. After cells were stained with DAPI, the formation of apoptotic cells could be observed under the fluorescence microscope. With the extension of GH, the apoptosis rate of cells increased significantly, compared with control group, the early apoptotic rate of GH group increased significantly at 12 and 24 hours (P<0.05 and 0.01). Western Blotting showed that compared with control group, the levels of Bax, Cleaved Caspase 3 and Cytochrome C protein increased significantly (P<0.05 and 0.01) and the levels of Bcl-2 and Caspase 3 protein decreased significantly (P<0.05, 0.01). Conclusion GH induces apoptosis of breast cancer MCF-7 cells through mitochondrial pathway
[中图分类号]
[基金项目]
国家自然科学基金(81703389)