冬凌草甲素抑制人肝癌SMMC．7721细胞增殖及诱导细胞凋亡的机制研究

目的研究冬凌草甲素对人肝癌细胞株SMMC-7721细胞的抑制作用及诱导凋亡机制。方法采用不同浓度的冬凌草甲素作用于人肝癌SMMC-7721细胞，以四甲基偶氮唑蓝（MTT）法检测细胞抑制率，倒置显微镜观察不同浓度组的细胞形态，RT—PCR法检测细胞Survivin、Bcl-2、BaxmRNA的表达，WesternBlot法检测细胞Survivin、Bcl-2、Bax的蛋白表达。结果MTT比色法显示不同浓度的冬凌草甲素可抑制人肝癌SMMC．7721细胞的增殖，抑制作用呈时间和剂量依赖性。冬凌草甲素作用48h后细胞表现出特异性凋亡。RT—PCR法和WesternBlot法显示，人肝癌SMMC-7721细胞的BaxmRNA和Bax蛋白随冬凌草甲素浓度增加而表达增加，Bcl-2、SurvivinmRNA和Bcl-2、Survivin蛋白随药物浓度增加而表达下降。结论冬凌草甲素能抑制人肝癌SMMC-7721细胞的生长及诱导细胞发生凋亡，降低Sur—vivin、Bcl-2表达和上调Bax表达可能是诱导细胞发生凋亡的机制。

Orinidon inhibits cell growth on human hepatocellular carcinoma SMMC-7721 cells by induction of apoptosis

Objective To investigate the mechanism of cell growth inhibition and apoptosis inducement of oridonin on human hepatocellular carcinoma SMMC-7721 cells. Methods In vitro, human hepatocellular car- cinoma cell line SMMC-7721 was treated by oridonin in different concentrations. The inhibitory effect of cell growth was assayed by MTI＇; The changes of cell morphology were observed by inverted microscope, the mRNA expressions of Survivin, Bcl-2, Bax were analyzed by RT-PCR; Western Blot was taken to detect Survivin, Bcl-2, Bax protein expression. Results MTT assay indicated that the inhibitory effect of orinidon on the prolif- eration of SMMC-7721 cell was found in dose-and-time dependent manner. Marked morphological changes of cell apoptosis were obseved clearly after the cells exposed to oridonin for 48 hours. RT-PCR assay and Western Blot showed that the expression of Bax mRNA and protein were up-regulated and Bcl-2, Survivin mRNA and protein was down-regulated by orinidon at 48 hours with concentration increased. Conclusions Oridonin has significant anti-proliferation effects by inducing apoptosis on hepatocellular carcinoma ceils in vitro, down regu- lation of Survivin and Bcl-2 as well as up-regulation of Bax expressions may be the important apoptotic inducing mechanisms.