紫草素对人肝癌HepG2细胞生长的影响及机制研究

Effect and Mechanism of Shikonin on the Growth of Human HepG2 Cells

目的:研究紫草素对人肝癌HepG2细胞生长的影响并探讨其可能的作用机制。方法:以不同浓度紫草素(0.3、0.5、0.7μg/ml)和顺铂(40μg/ml)分别干预对数生长期人肝癌HepG2细胞;采用MTT比色法测定细胞增值抑制率,通过流式细胞术检测细胞周期和细胞凋亡状况,采用RT-PCR法检测细胞中Bax mRNA、Bcl-2 mRNA表达并计算Bax/Bcl-2比值,采用Western blotting技术检测Caspase-3蛋白表达。结果:经紫草素干预48 h能够显著提高HepG2细胞增殖抑制率,延长细胞周期G_0/G_1期并缩短G_2/M期,提高细胞凋亡率(Apoptosis Index,AI),上调Bax mRNA表达并下调Bcl-2 mRNA表达、提高Bax/Bcl-2表达比值,上调Caspase-3蛋白表达,上述作用均具有一定的剂量依赖性。结论:紫草素能够通过抑制增殖并促进凋亡而对人肝癌HepG2细胞生长起到一定抑制作用,其机制可能与紫草素能够调节细胞周期以及调节凋亡相关基因、蛋白表达有关。

Objective ：To investigate the effect and mechanism of Shikonin on the growth of human HepG2 ceils. Methods ： The human HepG2 ceils in logarithmic growth phase was treated with Shikonin （ 0.3, 0.5, 0.7μg/ml） and Cisplatin （40μg/ml）. The cellular growth inhibition rate was calculated by MTT, and the cell cycle and apoptosis rate were analyzed by flow eytometry. The expressions of Bax mRNA and Bcl -2 mRNA were detected by RT - PCR, and the ratio of Bax/Bcl - 2 was calculated. The expression of Caspase - 3 pro-tein was detected by Western blotting. Results：The cellular growth inhibition rate of human HepG2 cell by Shikonin was significantly increased; the cell cycle was arrested at G0/G1 phase, and the apoptosis rate was significantly increased; the expression of Bax mRNA was significantly increased, while the expression of Bcl -2 mRNA was significantly decreased, and the ratio of Bax/Bcl - 2 was significantly increased ; the expression of Caspase - 3 protein was significantly increased ; all of the above effects were dose - dependent with a certain. Conclusion ： Shikonin has an inhibitive effect on the growth of human HepG2 cell by inhibiting proliferation and inducing apoptosis, which may be related to its effect of altering the cell cycle and the expression of apoptosis- related genes and proteins.