目的:研究氯喹与地西他滨联合应用对白血病K562和KG-1a1Aor1a细胞凋亡的影响,探讨自噬对地西他滨诱导白血病细胞凋亡的作用,阐明其作用机制。方法:体外培养髓性白血病K562和KG-1a1Aor1a细胞,分为空白对照组、地西他滨(10μmol·L-1)单用组和氯喹(50μmol·L-1)联用地西他滨组(联用组)。联用组细胞使用氯喹孵育6h后再与其他组细胞同时开始实验。孵育24及48h后,CCK-8法检测细胞数量并计算增殖抑制率,流式细胞术检测细胞凋亡率和线粒体膜电位。Q-PCR法检测Atg7及Atg12基因表达水平,Western blotting法检测LC3蛋白表达。结果:孵育24及48h后,与空白对照组比较,地西他滨和联用组K562和KG-1a1Aor1a细胞数量数量明显减少(P〈0.05或P〈0.01);凋亡率明显升高(P〈0.05或P〈0.01),线粒体膜电势明显增加(P〈0.05或P〈0.01);与地西他滨组比较,联用组K562和KG-1a1Aor1a细胞明显减少,细胞数量凋亡率明显升高(P〈0.05)。孵育24h后,与空白对照组比较,地西他滨组K562和KG-1a1Aor1a细胞Atg7、Atg12和LC3-Ⅱ/LC3-Ⅰ相对表达水平明显升高(P〈0.05或P〈0.01);与地西他滨组比较,联用组K562和KG-1a1Aor1a细胞Atg7、Atg12和LC3-Ⅱ/LC3-Ⅰ相对表达水平明显降低(P〈0.05或P〈0.01)。结论:地西他滨具有促进白血病细胞凋亡的作用,而联用氯喹可以抑制自噬从而增强地西他滨诱导细胞凋亡的作用。
Objective:To study the influence of chloroquine combined with decitabine in the apoptosis of leukemia K562 cells and KG-1a1Aor1 acells,to explore the effect of autophagy on the leukemia cell apoptosis induced by decitabine,and to clarify its mechanism.Methods:The leukemia K562 and KG-1a1Aor1 acells were cultivated in vitro and divided into blank control group,decitabine group(10 μmol· L^-1)and chloroquine(50μmol·L^-1)combined with decitabine group(combined group).The leukemia cells in combined group were pre-treated with chloroquine for 6h before experiment.After treatment with drugs for 24 and 48h,the number of cells was detected and by CCK-8 method the inhibitory rates of proliferation cells were calculated;the apoptotic rates and mitochondrial membrane potential were detected by flow cytometry.Q-PCR method was carried out to determine the gene expression levels of Atg7 and Atg12,and Western blotting was used to test the protein expression of LC3.Results:After treatment for 24 and 48h,the number of K562 and KG-1a1Aor1 acells in decitabine group and combined group were decreased compared with blank control group(P〈0.05 or P〈0.01);the apoptotic rates and mitochondrial membrane potential were remarkably increased(P〈0.05 or P〈0.01).Compared with decitabine group,the number of K562 and KG-1a1Aor1 ain combined group was significantly decreased,and the apoptotic rates were remarkably increased(P〈0.05).After treatment for 24 h,the expression levels of Atg7,Atg12 and LC3-Ⅱ/LC3-Ⅰ in the leukemia K562 and KG-1a1Aor1 acells in decitabine group were significantly increased compared with blank control group(P〈0.05 or P〈0.01);the expression levels of Atg7,Atg12 and LC3-Ⅱ/LC3-Ⅰ in the leukemia K562 and KG-1a1Aor1 acells in combined group were significantly decreased compared with decitabine group(P〈0.05 or P〈0.01).Conclusion:Decitabine could promote the apoptosis of leukemia cells,and the inhibition of autophagy by chloroquine can promote the apoptosis induc