紫杉醇对U373细胞周期阻滞及增殖抑制的机制研究

目的研究紫杉醇(PTX)诱发神经胶质瘤U373细胞的周期阻滞和增殖抑制的相关机制。方法 MTT检测细胞增殖抑制率,流式细胞术检测细胞周期分布,免疫细胞荧光化学观察细胞形态学变化,RT-PCR和Western blot检测细胞周期相关CyclinB1、CyclinD1、CDK1、CDK2和p53的表达变化。结果 PTX可以明显抑制U373细胞的增殖活性,抑制作用呈时间浓度依赖性;细胞周期分析显示,实验组细胞G2/M期比例增高;细胞免疫荧光检测实验组细胞阻滞于有丝分裂期;RT-PCR和Western blot显示,PTX可以增加CDK1和CyclinB1表达,降低CyclinD1表达(P<0.05),而对CDK2无明显影响。结论 PTX能够抑制神经胶质瘤U373细胞增殖,引起有丝分裂期阻滞,诱导细胞凋亡,与其细胞周期相关蛋白表达水平密切相关。

The mechanism of the induction of cell cycle arrest and inhibition on U373 cells by PTX

Aim To investigate the effect of U373 cells cycle arrest and inhibition by paclitaxel,and to explore its molecular mechanism.Methods The anti-proliferative effect on U373 cells was determined by MTT assay;the cell cycle was measured by flow cytometry;the cells were stained with anti-α-tubulin-FITC and DAPI,and its morphological changes were observed under fluorescence microscope;the CyclinB1,CyclinD1,CDK1,CDK2,and p53 expression levels of cells treated with PTX were detected in mRNA,protein level by RT-PCR and Western blot.Results Cell proliferation was inhibited in U373 cells treated with PTX,and the inhibitory effects were in time and dose dependent manners.Cell cycle analysis showed that the G2/M phase of U373 cells treated with PTX increased significantly compared with the control group,and the effect of mitotic phase arrest was showed by immunocytochemistry.The RT-PCR and Western blot results showed that PTX could up-regulate the expressions of CyclinB1 and CDK1 and down-regulate the expression of CyclinD1,but could have little influence over the expression of the CDK2.Conclusion PTX can produce the anti-proliferation effect on U373 cells and induce cells M phase arresting,which is closely related to the expression of genes associated with cell cycle.