诱导分化促进肺癌细胞对化疗药诱导凋亡的敏感性

Induction of cell differentiation improves apoptosis of lung carcinoma cell line triggered by prior exposure to anti-tumor drug

目的 探讨诱导分化能否增加抗肿瘤药物诱导肿瘤细胞的凋亡。方法 将肺癌细胞株A5 49先用小剂量细胞毒抗肿瘤药处理 ,造成肺癌细胞的DNA损伤。然后用不含有和含有不同浓度的诱导分化剂的培养液继续培养 3天。MTT试验作细胞生长抑制测定 ,流式细胞仪细胞DNA含量及细胞周期分析 ,原位细胞凋亡末端转移酶DNA缺口标记及Hoechst332 5 8染色荧光显微镜下细胞形态等多指标作为细胞凋亡的定量和定性分析。结果 维甲酸 (RA)在体外能增加抗癌药足叶乙甙 (VP16 )对肺癌细胞的生长抑制 ,并能促进肺癌细胞的凋亡 ,通过流式细胞仪测定凋亡率RA +VP16组分别是单用VP16组和RA组的 2 .8倍和 2 .2倍。结论 为临床上通过调节细胞分化和细胞周期促进抗肿瘤药诱导肿瘤细胞凋亡 ,从而达到提高疗效和降低药物毒副作用的目的提供了理论依据。

Objective To test the hypothesis that inducing agents of cell differentiation will increase the apoptosis triggered by anti-tumor drugs.Methods Human lung adenocarcinoma cell line A549 was treated with DNA-damaging anti-tumor drug etoposide(VP16) for a short time.Following drug removal,the cells were postincubated with or without all-trans retinoic acid(RA),which induces myelocytic differentiation.Multiparameter such as MTT,Flow cytometry,the analysis of apoptosis-associated DNA breakage in situ,and cell morphological observation with fluorescence microscope of Hoechst 33258 straining were used to investigate cell growth condition and determin the mode of cell death.Results RA could increase the growth retardation and apoptosis of DNA-damaged cells,which were treated by anti-tumor durg prior to induction of differentiation.The growth inhibition rates of A549 cell line treated by RA+VP16 increased 38%～120% than that only treated by anti-tumor drug VP16.By analysis of flow cytometry,the percentage of apoptosis cells was 2.8 or 2.2 times as much as that when the agents were used individually.Conclusion The present data suggest that the strategy of modulating cell differentiation or cell cycle to enhance apoptosis induced by anti-tumor durgs should lead to improved treatment efficacy and decrease drug toxicity.