RNA干扰对NB4细胞凋亡的影响

Effects of synthetic small interfering RNAs on NB4 cell apoptosis

目的:探讨靶向PML-RARαmRNA的siRNAs对急性早幼粒白血病NB4细胞株凋亡的影响。方法:体外培养人白血病细胞株NB4细胞,以不同浓度的siRNAs分别转染细胞,MTT法检测siR-NAs对NB4细胞的抑制作用,细胞形态学观察和流式细胞仪检测细胞凋亡。结果:siRNA转染NB4细胞后,对细胞的增殖有明显的抑制,siRNA1244的24hIC50为46.578nM;细胞形态学观察可见明显的细胞凋亡现象,流式细胞仪检测也证明转染siRNA后细胞凋亡率增加,转染50nM siRNA1244的NB4细胞,24h后凋亡率从4.29%增至59.35%。结论:siRNA1244诱导NB4细胞凋亡效果最为明显,并且与抑制细胞增殖的效应一致,具有抗急性早幼粒细胞白血病效应,它的作用分子机制很可能是下调PML-RARα基因的表达而抑制增殖并诱导凋亡。

Objective： To explore the inhibition efficiency of small interfering RNAs（siRNAs） on proliferation and apoptosis of acute promyelocytic leukemia cell line NB4.Methods： NB4 cells were cultured in vitro and transfected with siRNAs at different concentrations.The proliferation inhibition was evaluated by MTT assay,and apoptosis was determined by FCM and the morphology apoptotic cells were identified by Giemsa-Wright staining.Results： After transfection,the proliferation was significantly inhibited,apoptotic cells were obviously observed,24 h IC50 of siRNA1244 was 46.578 nM,and increased apoptosis was also confirmed by FCM.The apoptosis rate of NB4 transfected with siRNAs at concentration of 50 nM increased from 4.29% to 59.35%.Conclusions：siRNA1244 showed significant inhibition effects on NB4 cell apoptosis,which is consistent with its inhibition on proliferation.Its anti-acute promyelocytic leukemia effect probably related to the down regulated PML-RAR alpha gene expression which inhibit proliferation but induce apoptosis.