葫芦素E诱导肝癌细胞凋亡及其机制

Mechanism of cucurbitacin E-induced apoptosis of hepatocarcinoma cells

目的探讨葫芦素E对肝癌细胞形态学方面的影响及其机制。方法用不同浓度的葫芦素E孵育HepG2细胞6h,分别通过MTT检测药物对细胞的生长抑制作用、激光共聚焦显微镜观测细胞形态变化、流式细胞仪检测细胞凋亡比率、Western blot检测凋亡相关蛋白的表达变化。结果经过葫芦素E孵育后,HepG2细胞的生长受到显著抑制,形态学上胞膜发生翻转,为典型细胞凋亡形态变化,流式细胞检测发现,随着葫芦素E药物浓度的升高,细胞凋亡比率上升。同时,细胞中活化的Caspase 3蛋白比例上升。体内实验表明,葫芦素E可以提高Bax蛋白表达,促使裸鼠人原位移植肝癌细胞核酸断裂。结论葫芦素E可以影响HepG2细胞形态学改变,并诱导体内与体外HepG2细胞发生凋亡,而且呈现药物浓度依赖性。

Purpose To study the morphoalogical changes of HepG2 cells after cucurbitacin E（ CuE） treatment and the molecular mechanisms involved in this phenomenon. Methods HepG2 cells were treated with different doses of CuE for six hours and detected by confocal microscopy for morphological study. The inhibitory ratio of cell growth and percentage of cellular apoptosis were analyzed by MTT and flow cytometry,respectively. Additionally,the expression pattern of apoptosis-related protein was evaluated by Western blot.Results After treatment by CuE,HepG2 cells were observed as typical apoptotic cells. The results of MTT and FACS showed that CuE could inhibit cell growth and induce apoptosis of HepG2 in a dose-dependent manner. Also,pro-Caspase 3 was cleaved to active form Caspase 3. The results from in vivo experiments showed that CuE could up-regulate the expression of Bax and induce the cleavage of DNA in hepatocarcinoma cells. Conclusions CuE could trigger apoptosis of HepG2 cells characterized by apparent morphological changes,which provides scientific information for CuE treatment of liver cancer.