摘要
目的研究熊果酸(Ursolicacid,UA)抑制人食管癌Eca-109细胞增殖、诱导细胞凋亡的作用及机制。方法MTT比色法检测熊果酸对Eca-109细胞的增殖抑制作用;透射电镜观察经熊果酸处理后Eca-109细胞超微结构的改变;流式细胞术检测细胞周期变化及细胞凋亡率;Westernblot法检测P27kip1蛋白、凋亡相关蛋白Bcl-2、Bax的表达。结果20～50μmol/L熊果酸对Eca-109细胞具有显著的抑制作用(P<0.01);电镜下,18.32～36.65μmol/L熊果酸处理过的Eca-109细胞可见典型的凋亡形态及坏死形态;流式细胞检测显示细胞凋亡率及G0/G1期细胞随着熊果酸浓度的增加而增多,S期细胞逐渐减少;Westernblot检测结果提示熊果酸能使Bcl-2表达下降而Bax、P27kip1增加。结论熊果酸对人食管癌细胞系Eca-109具有显著的增殖抑制、诱导细胞凋亡作用。其作用与提高P27kip1蛋白的表达,将细胞阻滞在G0/G1期,下调Bcl-2的表达和增加Bax的表达有关。
Objective To investigate the effects and possible mechanisms of ursolic acid （UA） on inhibiting proliferation of human esophageal carcinoma cell Eca - 109 and inducing its apoptosis. Methods Cell proliferation was determined by MTT assay. Electron microscope was used to observe the uhrastructural changes of Eca - 109 induced by UA. Cell cycle and apoptotic rate were analyzed by flow cytometry （FCM）, and the expression of P27^kip1, Bcl -2 and Bax were detected by Western blot method. Results UA could significantly inhibit the growth of Eca - 109 cells（ P 〈 0. 01） at the concentration of 20 - 50 μmol/L. The cell apoptosis and necrosis of Eca - 109 cells after treatment with UA （18.32- 36.65 μmol/L） were obvious under electron microscope. The apoptotic rate of Eca - 109 cells and the G0/G1 cells increased gradually, while the S - phase cells decreased gradually with the gradual increase of UA concentration. Western blot results showed that the expression of Bcl - 2 of ECa - 109 cells were down - regulated, while the expression of Bax and P27^kip1 up- regulated. Conclusion Ursolic acid has a significantly effect on inhibiting proliferation and inducing apoptosis of Eca - 109 cells. Blocking Eca - 109 cells at the G0/G1 phase by enhancing the expression of P27^kip1 protein, reducing the expression of Bcl - 2 and increasing the expression of Bax may be the mechanism of ursolic acid inducing Eca - 109 apoptosis.
出处
《中药新药与临床药理》
CAS
CSCD
2008年第6期454-458,共5页
Traditional Chinese Drug Research and Clinical Pharmacology
基金
重庆市科委自然科学基金资助项目(CSCT
2006BB5297)。
