地西他滨联合柔红霉素对HL-60细胞株凋亡作用的探讨

目的观察小剂量地西他滨（DAC）单用或联合柔红霉素（DNR）对白血病细胞株HL-60的凋亡作用及对抑癌基因PTENmRNA表达的影响。方法以不同浓度的DAC、DNR单药及联合处理HL．60细胞株，应用四甲基偶氮唑蓝（M1Tr）法、流式细胞术检测不同时相药物对细胞的凋亡作用；采用实时荧光定量聚合酶链反应（FQ—PCR）技术检测不同浓度组中HL-60细胞PTENmRNA表达。结果DAC、DNR单药对HL-60细胞的生长抑制作用呈剂量、时间依赖性，联合用药组的抑制作用则更为明显72h抑制率为（80．23±1．71）％，P〈0．001]；5．0μmol／LDAC联合1．0μmol／LDNR作用72h细胞凋亡率最高，抑制作用均较DAC和DNR单药组明显（F=30．199，P〈0．001）；不同浓度DAC与DNR联用后，细胞PTENmRNA表达量增加，呈浓度依赖性，明显高于对照组及DNR单药组（F=578．218，P〈0．001）。结论DAC能显著抑制HL-60细胞的增殖并诱导其凋亡，与DNR联合对HL-60细胞增殖抑制作用有协同效应，其机制可能与DAC的去甲基化作用使PTENmRNA的表达量增加有关。

Effect of decitabine combined with daunorubicin on apoptosis of HL-60 cell line

Objective To observe the cell proliferation inhibition of DNA methyhransferase （DNMT） inhibitors decitabine （DAC） combined with daunorubicin （DNR） in human leukemia cell line HL-60. Methods The effects of DNR and DAC were examined in HL-60 cells by cell viability using MTT method, and cell death using flow cytometric （FCM）. Results DAC,DNR single drug application showed their effects on cell proliferation was dependent of dose and time, the inhibition effect of combined treatment group was much clearer inhibition ratio of 72 hours was （80.23±1.71） %, P 〈 0.001]. The highest apoptosis rate was at 5.0 μmol/L DAC combined with 1.0 μmol/L DNR for 72 hours, which was statistic significant （F = 30.199, P 〈 0.001）. Combinations of different concentrations of DAC and DNR increased expression of PTEN mRNA in concentration-dependent manner, which was significantly higher than the control group and DNR single drug group （F = 578.218, P 〈 0.001）. Conclusions DAC can significantly inhibit the proliferation of HL-60 cells and induce apoptosis, synergistic effect can be observed when DAC combined with DNR. The underlying mechanism can be due to DAC demethylation effect to increase PTEN mRNA expression.