环氧合酶-2抑制剂对K562白血病细胞增殖及凋亡的影响

目的:体外观察非甾体药物选择性环氧合酶-2(COX-2)抑制剂NS-398对白血病细胞株K562细胞增殖及凋亡影响。方法:采用噻唑蓝法观察NS-398对K562细胞增殖的影响,流式细胞仪检测细胞周期的改变及凋亡百分率的变化,DNA梯状电泳检测凋亡的发生。Western印迹法检测K562细胞半胱氨酸天冬氨酸特异性蛋白酶Caspa-se-3和COX-2的表达。结果:NS-398呈剂量依赖性的方式抑制K562细胞增殖,并诱导其凋亡。并呈浓度依赖性改变细胞周期的分布,一方面增高Go/G1期细胞比例,另一方面降低S期和G2/M期细胞比例,与对照组相比差异具显著性(P<0.05)。NS-398干预的K562细胞Caspase-3的蛋白表达均显著升高,而COX-2的蛋白表达降低,并呈浓度依赖性。结论:体外NS-398能有效的发挥抗K562细胞白血病效应,对白血病细胞增殖有抑制作用并诱导其凋亡,这可能与抑制COX-2表达及上调Caspase有关。

Effect of selective cyclooxygenase2 inhibitor NS-398 on proliferation and apoptosis of K562 leukemia cell

OBJECTIVE To investigate the effect of cyclooxygenase-2 inhibitor,NS-398,on proliferation and apoptosis in leukemia cell line K562 line.METHODS The effect of NS-398 on the prolifertion of K562 cells was evaluated by MTT.The apoptotic cells were determined by DNA flagment analysis and flow eytometrie(FCM)-analysis.Western blotting analysis was applied for determination of caspase-3 and COX-2 expression in K562 cells.RESULTS NS-398 inhibited cell proliferation and induced apoptosis in K562 in a concentration-dependent manner.DNA ploidy analysis showed that S phase cells were significantly decreased with NS-398 concentration increasing.The quiescent G0/G1 phase was accumulated with decreasing of COX-2 protein.Whereas NS-398 stimulated caspase-3 expression at protein level in K562 cells.CONCLUSION NS-398 significantly inhibits the proliferation and induces apopotosis in K562 cells.Mechanisms may be involved in accumulation of quiescent G0/G1 phase and decrease in COX-2 expression and up-reugulated caspase-3 expession.