叶酸诱导人肝癌细胞凋亡及其机制的研究

STUDY ON APOPTOSIS OF HEPATOCARCINOMA CELLS INDUCED BY FOLIC ACID AND ITS MECHANISM

目的 研究叶酸诱导人肝癌细胞凋亡的作用及其机制。方法 应用叶酸连续处理体外培养的人肝癌细胞(SMMC 772 1) ,4天后光镜及电镜观察细胞形态改变 ,细胞计数测定细胞生长及增殖情况 ,DNA凝胶电泳分析DNA改变 ,流式细胞仪检测细胞周期分布、细胞凋亡指数及凋亡相关基因及其表达的改变。结果 10 μg/ml叶酸可诱导SMMC 772 1细胞出现凋亡特征性形态改变 ,其细胞DNA电泳呈现“梯状”断裂现象 ,细胞凋亡指数为 16 8% (空白对照组为6 9% ) ,S期细胞减少 ,细胞生长和增殖被明显抑制 ,且凋亡相关基因fas和p5 3表达增加 ,而bcl 2和TGF β1表达降低。结论 叶酸具有诱导人肝癌细胞凋亡的作用 。

Objective To study the apoptosis of human hepatocarcinoma c ell line induced by folic acid and its mechanism.Methods Human hepatocarcinoma SMMC-7721 cells cultured in vitr o were treated with folic acid (FA) for 4 days. The morphology of the cells were observed by microscopy. The cell growth and proliferation were measured by cell counting. The DNA break was examined by gel electrophoresis. The cell cycle, ap optosis index (AI) and the expression of apoptosis associated gene were analysed by flow cytometry. Results 10 μg/ml FA could induced the apop tosis of SMMC-7721 cells. The morphologic charateristics of apoptotic cells wer e observed in the treated group. The DNA of cells presented 'ladder' break. Th e cell growth and proliferation were inhibited obviously, and the AI is 16.8%(th e control group is 6.9%). The cells were arrested in G 0/G 1 phase and cellula r DNA synthesis were inhibitied. The expression of apoptosis associated gene fas and p53 were up regulated, the expression of bcl-2 and TGF-β1 were down regu lated.Conclusion FA can induce apoptosis of SMMC-7721 cells. I ts mechanism might relate to modulation of the apoptosis associated ge ne expression.