藤黄酸体外诱导人结直肠癌细胞凋亡的机制

Gambogic Acid induced apoptosis of colorectal cancer cells via classical mitochondria-dependent caspase-3 pathway

目的探讨藤黄酸对体外培养人结直肠癌细胞株增殖凋亡的影响以及诱导凋亡的可能机制。方法 CCK-8法检测不同浓度(0、1、2、4μmol/L)不同时间点(0、24、48、72 h)藤黄酸处理对人结直肠癌细胞株(SW480、LOVO细胞)增殖活性影响;流式细胞术检测细胞凋亡情况;免疫荧光检测细胞Cleaved caspase-3表达;Western blot技术检测Bax、Bcl-2、细胞色素C、多聚ADP核糖聚合酶和Cleaved caspase-3蛋白的表达。结果藤黄酸对SW480、LOVO细胞均有显著的增殖抑制作用,抑制率与药物浓度和作用时间呈正相关;相同处理时间,随着藤黄酸浓度增加,细胞凋亡的百分比增加;免疫荧光染色发现藤黄酸作用24 h后,细胞Cleaved caspase-3表达增加;藤黄酸处理SW480/LOVO细胞后,Bax/Bcl-2比值、细胞色素C、多聚ADP核糖聚合酶和Cleaved caspase-3蛋白表达均明显增加。结论藤黄酸可能通过激活线粒体凋亡通路体外诱导人结直肠癌细胞株的凋亡。

Objective To investigate the antitumor activity of Gambogic acid（ GA） in human colon cancer SW480/LOVO cells. Methods Colon cancer SW480/LOVO cells were used for in vitro experiments in this study. Relative cell viability was assessed using CCK-8 assays. Cell apoptosis was quantified by flow cytometry. Western blot analyses were used to evaluate gene and protein expression levels. Results GA inhibited the growth of SW480/LOVO cells in concentration-and time-dependent manners. Moreover,typical morphological changes associated with apoptosis were observed through fluorescent staining of Cleaved caspase-3 expression. As a result of the treatment with GA,significant increases in the ratio of Bax/Bcl-2,expression of cytochrome c,cleaved PARP,and Cleaved caspase-3 protein were consecutively observed. Conclusion These results further demonstrates that GA induces apoptosis of colorectal cancer cells through the molecular mechanism from the classical mitochondria-dependent Cleaved caspase-3 pathway.