三氧化二砷增强TRAIL杀伤人A549细胞的作用及机制研究

Mechanism of synergistic anti-tumor effect of arsenic trioxide combined with TRAIL on human A549 cells

目的研究三氧化二砷(As2O3)增强重组人肿瘤坏死因子相关凋亡诱导配体(TRAIL)对人非小细胞肺癌细胞(A549)的作用及其作用机制。方法采用四甲基偶氮唑蓝比色(MTT)法检测As2O3及联合TRAIL对人A549的IC50值;不同浓度As2O3与TRAIL联合作用48 h后,流式细胞术检测细胞凋亡率;RT-PCR检测Survivin、Caspase-3 mRNA表达变化。结果 As2O3有抗肿瘤活性,IC50值为(42.44±0.66)μmol.L-1;As2O3与TRAIL联用时IC50值为(7.04±0.19)μmol.L-1;As2O3协同增强TRAIL的抗肿瘤活性,CDI值为0.94。联合药物组作用48h后,随As2O3浓度增高Survivin mRNA的表达降低,Caspase-3mRNA的表达增强。结论 As2O3是有效的化疗药物,通过下调Survivin mRNA的表达,上调Caspase-3 mRNA的表达,逆转A549的耐药性,协同TRAIL增强对肺癌细胞的杀伤作用。

Aim To study the synergistic mechanism between arsenic trioxide and recombinant human tumor necrosis factor related apoptosis inducing ligand（TRAIL） against A549 cells.Methods The function of inhibition of human non-small-cell lung cancer cell line A549 treated with different doses of As2O3 combined with TRAIL was detected by the assay of 3-（4,5-Dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT）.Flow cytometry with PI stain was used to detect the apoptotic rate after treatments for 48 h.Survivin and Caspase-3 mRNA level of A549 cells was detected by RT-PCR before and after treatments for 48 h.Results As2O3 and As2O3 combined with TRAIL had anti-tumor effect with IC50 of（42.44±0.66） μmol·L-1 and（7.04±0.19） μmol·L-1,respectively.Compared with As2O3 or TRAIL alone,As2O3 combined with TRAIL after 48h could increase the apoptotic ratio significantly（P0.05）.RT-PCR showed that the expression of Survivin in combined group was obviously less than that in As2O3 and TRAIL alone and control group,but the expression of Caspase-3 was on the contrary.Conclusion As2O3 is a cytotoxinic drug,As2O3 combined with TRAIL has synergistic anti-non-small-cell lung cancer cell effect in vitro,and its mechanism may be that it can down-regulate the expression of Survivin and up-regulate the expression of Caspase-3.