组蛋白去乙酰化酶抑制剂对骨肉瘤MNNG/HOS细胞凋亡的影响

Effects of histone deacetylase inhibitor on apoptosis of osteosarcoma MNNG/HOS cells in vitro

目的:探讨组蛋白去乙酰化酶抑制剂(histone deacetylase inhibitor,HDACI)曲古抑霉素A(trichostatin A,TSA)对体外培养的骨肉瘤MNNG/HOS细胞凋亡的影响。方法:用50、100、200、300和500nmol/L TSA分别作用体外培养的骨肉瘤MNNG/HOS细胞12、24和48h,在透射电子显微镜下观察细胞形态学变化,应用MTT、FCM和TUNEL法检测TSA对骨肉瘤细胞增殖、细胞周期和细胞凋亡的影响。结果:TSA具有抑制骨肉瘤MNNG/HOS细胞增殖的作用,并且随着TSA浓度的增加和作用时间的延长而增强(P<0.01)。FCM检测结果显示,与对照组比较,300nmol/L TSA作用组G1期细胞减少,G2/M期细胞增加,细胞凋亡率增加,差异有统计学意义(P<0.05)。TUNEL法检测结果显示,细胞凋亡指数随着TSA浓度的增加和作用时间的延长而上升,与对照组比较差异有统计学意义(P<0.05)。透射电子显微镜下观察发现,TSA作用后,凋亡的骨肉瘤细胞细胞质浓缩,并可见凋亡小体。结论:TSA可抑制体外培养的骨肉瘤MNNG/HOS细胞增殖并诱导其凋亡,可能与G2/M期细胞周期阻滞有关。HDACI可能成为一种新的骨肉瘤治疗策略及抗肿瘤药物。

Objective：To explore the effects of histone deacetylase inhibitor trichostatin A（TSA）on apoptosis of osteosarcoma MNNG/HOS cells in vitro.Methods：The osteosarcoma MNNG/HOS cells were cultured and treated with 50,100,200,300 and 500 nmol/L TSA for 12,24 and 48 h.The morphological changes of osteosarcoma MNNG/HOS cells were observed under a transmission electron microscope.MTT colorimetric method was performed to evaluate the cytotoxic effects of TSA on MNNG/HOS cells.The cell cycle distribution and apoptosis of MNNG/HOS cells were detected by flow cytometry（FCM）techniques and TUNEL methods.Results：TSA inhibited the proliferation of MNNG/HOS cells in a dose-and time-dependent way（P〈0.01）.Compared with the control group,the apoptosis rate and the percentage of MNNG/HOS cells in G2/M phase were increased,and the percentage of MNNG/HOS cells in G1 phase was decreased in 300 nmol/L TSA treatment group（P〈0.05）.The apoptotic index of MNNG/HOS cells in TSA treatment group was increased in a dose-and time-dependent way（P〈0.05）.TSA induced apoptosis with the appearance of condensation of cytoplasm and apoptosis body under transmission electron microscope.Conclusion：TSA inhibited the proliferation and induced the apoptosis of osteosarcoma MNNG/HOS cells.This effect may be related with G2/M phase arrested.The histone deacetylase inhibitor TSA can be considered as a novel therapeutic strategy and drug for osteosarcoma.