甘草次酸诱导U266细胞凋亡及对Survivin表达的影响

Glycyrrhetinic Acid Induces Apoptosis and Alters Survivin Gene Expression in Human Myeloma Cell Line U266

本研究旨在观察甘草次酸(glycyrrhetinic acid,GA)对人骨髓瘤细胞系U266增殖、凋亡及survivin表达的影响。用MTT法检测GA对U266细胞增殖活性的影响;流式细胞仪检测不同浓度GA作用于U266细胞后细胞凋亡,细胞周期的变化;扫描电子显微镜观察细胞凋亡的形态学变化;实时定量PCR检测GA对U266细胞survivin基因表达的影响。结果表明:GA对U266细胞有增殖抑制作用,其抑制作用呈现为时间和浓度依赖性;GA可以诱导U266细胞凋亡;扫描电子显微镜下可见核仁染色质边集,凝聚成块;GA可以诱导U266细胞周期阻滞于G0/G1期,表现为G0/G1期细胞比例升高,而G2/M及S期细胞比例下降。GA可以下调U266细胞survivin基因的表达,下调作用与浓度呈正相关。结论 :CA能抑制U266细胞增殖,呈浓度和时间依赖性,诱导其凋亡,其作用机理可能与细胞周期阻滞于G0/G1期和下调survivin基因表达有关。

This study was aimed to investigate the effects of glycyrrhetinic acid （ GA ） on proliferation , apoptosis and survivin mRNA expression in human myeloma cell line U266 in vitro. Cell proliferation was assayed by MTr method. Both cell apoptpsis and cell distribution in cell cycle were analyzed by using flow cytometry. Scanning electron microscopy was used to observe the morphological changes in U266 cells induced by GA. Expression of survivin mRNA was detected by quantitative real-time reverse transcription-polymerase chain reaction. The results showed that GA inhibited proliferation of U266 cells in a time- and dose-dependent manners in vitro. GA presented apoptosis induction potency to U266 cells,obvious changes in morphology of U266 cells was observed under scanning electron microscope. The cells were arrested at the G0/G1 phase, showing the accumulation in G0/G1 phase, reduction of ceils in G2/M phase and S phase. GA could down-regulate the expression of survivin gene in U266 cells in a dose-dependent manner. It is concluded that GA can inhibit proliferation of U266 cells in a time- and dose-depedent manners and induce apoptosis of this cell line in vitro through arresting G0/G1 phase and down-regulating expression of survivin.