曲古菌素A诱导髓系白血病细胞株U937细胞凋亡的分子途径

A study on molecular pathway of apoptosis of U937 cells in myelocytic leukemia cell lines induced by trichostatin A

目的 研究曲古菌素A(TSA)诱导髓系白血病细胞株U937细胞凋亡的分子途径。方法 不同浓度 ( 50、1 0 0、2 0 0、30 0、4 0 0nmol/L)的TSA在不同时间范围 ( 1 2、2 4、36、4 8和 6 0h)作用于U937细胞。用流式细胞仪检测细胞的凋亡率和Fas抗原 (CD95)的表达 ,用Westernblot法检测凋亡蛋白caspase 6、caspase 8和caspase 9的蛋白表达。结果 TSA诱导髓系白血病细胞株U937细胞的凋亡 ,并呈时间、剂量依赖性。在IC5 0 浓度 ( 30 0nmol/L)作用 2 4h凋亡细胞超过 50 % ;1 0 0～ 30 0nmol/LTSA作用 2 4h ,U937细胞Fas抗原表达也明显升高 (P <0. 0 1 )。TSA作用凋亡蛋白caspase 6、caspase 8和caspase 92 4h后 ,蛋白表达明显增高 (P <0 . 0 5)。结论 TSA诱导白血病细胞系U937凋亡涉及死亡受体参与的外源性途径和线粒体参与的内源性途径。

Objective To investigate the molecular pathway of apoptosis of U937 cells in myelocytic leukemia cell lines induced by trichostatin A(TSA).Method Cultured U937 cells were treated with TSA at different concentration of(50,100,200,300 and 400)nmol/L and 300 nmol/L for varied times(12,24,36,48 and 60 h).Flow cytometer was used to determine the rate of apoptosis of cells and the expression of Fas antigen(CD95)and Western blot was performed to determine the expression of caspase 6,caspase 8 and caspase 9.Rusult The apoptosis induced by the effect of TSA on U937 cells showed a time and dose dependent manner,with more than 50% of apoptosis at IC 50 of TSA for 24 h.The expression of Fas elevated significantly with 300 nmol/L TSA for 24 h(P<0.01).The expression of proteins increased significantly treated with 300 nmol/L of TSA for 24 h on apoptosis proteins caspase 6,caspase 8 and caspase 9(P<0.05).Conclusion Both TSA and endogenous mitochondria were involved in molecular pathway of apoptosis of U937 cells in myelocytic leukemia cell lines.