组蛋白去乙酰化酶抑制剂对HL-60细胞和K562细胞的抗肿瘤作用

为了观察组蛋白去乙酰化酶抑制剂丙戊酸（VPA）、曲古抑菌素（TSA）对K562细胞和HL-60细胞的抗肿瘤作用以及它们同全反式维甲酸（ATRA）之间的协同效应,采用绘制细胞生长曲线,计算半数抑制浓度（IC50）以及集落抑制试验等方法观察VPA,TSA以及全反式维甲酸（ATRA）在不同浓度或不同组合条件下对HL-60细胞和K562细胞的增殖抑制作用.采用细胞化学染色、分化抗原检测、细胞周期测定、联合NBT与MTT还原试验计算A（NBT）/A（MTT）值等方法分析细胞的分化或凋亡特点.结果显示,在体外培养体系中,VPA对HL-60细胞的IC50值低于对K562细胞的IC50值.ATRA能明显增强VPA、TSA对HL-60细胞以及VPA对K562细胞集落形成的抑制.HL-60经VPA处理后出现粒系表型,NBT还原率增加,CD11b表达增强,而K562细胞未显示分化迹象.结论：VPA和TSA抑制HL-60细胞增殖,VPA诱导HL-60细胞向粒系分化,这些作用均能被ATRA增强;VPA和TSA对K562细胞增殖抑制作用较弱,不能诱导K562细胞分化.

Antineoplastic Effect of Valproic Acid and Trichostatin on HL-60 and K562 cells

The objective of this study was to investigate antineoplastic effects of valproic acid (VPA) and trichostatin (TSA) on HL-60 and K562 cells in vitro, and the synergic effects of VPA or TSA in combination with ATRA. The inhibitory effects of VPA, TSA and ATRA in various concentrations and different combinations on prolifaration of HL-60 and K562 cells were observed by cell growth curves, 50% inhibitory concentration (IC_ 50), as well as inhibition of leukemia colony growth at different time points. The characteristics of cell differentiation or apoptosis were analyzed by cytochemical staining, differentiation antigen detection, cell cycle assay and A(NBT)/A(MMT) value determination. The results showed that HL-60 cell had a lower IC_ 50 of VPA and TSA compared with K562 cells. ATRA could significantly enhance the inhibition of VPA, TSA on clonegenicity of HL-60 cells and inhibition of VPA on clonegenicity of K562 cells. HL-60 cells treated with VPA displayed the phenotype of neutrophilic like cells, and showed the increases of NBT reduction rate and CD11b expression. No evidence for K562 differentiation was found. It is concluded that both VPA and TSA inhibit HL-60 cells growth in vitro. VPA induces differentiation of HL-60 cells to granulocyte. VPA and TSA have a moderate anti-proliferative effect on K562 cells. None of these agents induces K562 cell differentiation.