内皮抑素对HepG-2细胞生长的影响及机制研究

Effect of endostatin on proliferation and its mechanisms

目的探讨内皮抑素对人肝癌细胞株HepG-2细胞生长增殖和血管内皮生长因子(VEGF)基因表达的影响及其可能的机制,为临床肝癌治疗中内皮抑素的应用提供实验依据。方法采用MTT法检测不同浓度的内皮抑素作用不同时间后对HepG-2细胞生长的抑制作用;流式细胞仪检测内皮抑素对细胞凋亡及周期分布的影响;免疫组织化学法检测内皮抑素作用前后HepG-2细胞中survivin蛋白表达的改变;Western blotting法检测加药前后HepG-2细胞中VEGF蛋白表达的变化。结果内皮抑素能抑制HepG-2细胞的生长增殖(P<0.05),呈剂量-时间依赖性,并诱导细胞凋亡;免疫组织化学结果显示,内皮抑素作用后HepG-2细胞中survivin蛋白表达明显减少,差异具有显著性(P<0.01);Western blotting结果显示药物作用组中VEGF蛋白表达明显减少,差异具有显著性(P<0.01)。结论内皮抑素通过下调survivin蛋白的表达诱导HepG-2细胞的凋亡、抑制增殖,并能明显降低HepG-2细胞中VEGF的表达。

Purpose To evaluate the inhibitory effect and possible inhibitory mechanisms of endostatin on HepG-2 cells and expression of VEGF protein, so as to provide experimental evidence for clinical treatment of hepatoma with endostatins. Methods MTT assay was used to observe the inhibitory effects of endostatin on HepG-2 cells at various concentrations and different time points. Flow cytometer was used to detect the influence of endostatin on cell apoptosis and cycle distribution. The expression of survivin protein was analyzed by immunocytochemistry before and after endostatin treatment. VEGF protein content was determined by Western blotting. Results The growth of HepG-2 cells was significantly inhibited by endostatin in a dose-time-dependent manner （ P 〈 0. 05） and significant apoptosis was presented. Immunohistochemical results showed that the expression of survivin protein decreased obviously after being treated by endostation （P 〈 0. 01 ）. The expression of VEGF protein in HepG-2 cells was inhibited by endostatin as determined by Western blotting （ P 〈 0. 01 ）. Conclusions Endostatin can inhibit the proliferation and induce apoptosis of HepG-2 cells by decreasing expression of the survivin protein, and endostatin can inhibit the expression of VEGF.