PARP-1抑制剂ABT-888对依托泊苷诱导A549细胞增殖及凋亡的影响

Influence of the poly (ADP-ribose) polymerase inhibitor ABT-888 on the proliferation and apoptosis of A549 cells induced by etoposide

目的:探讨PARP抑制剂ABT-888在依托泊苷(VP-16)诱导的A549细胞增殖及凋亡中的作用。方法:常规培养A549细胞,经VP-16和(或)ABT-888处理24小时后,采用四甲基偶氮唑盐(MTT)比色法观察细胞的增殖情况,通过流式细胞术Annexin V-FITC/PI双染法分析细胞凋亡情况,通过彗星实验评价DNA损伤程度,通过Western blot法检测细胞线粒体和胞浆中线粒体相关细胞凋亡因子细胞色素c水平变化。结果:VP-16和ABT-888联用组的细胞增殖率明显低于对照组和VP-16组(P<0.01),细胞凋亡率则显著高于对照组和VP-16组(P<0.05);同时,VP-16和ABT-888联用组细胞DNA损伤水平较对照组和VP-16组明显加重(P<0.01),而细胞色素c在胞浆中的水平则显著高于对照组和VP-16组(P<0.01)。结论:PARP抑制剂ABT-888可通过抑制PARP活性,进而阻碍细胞DNA修复,来增强A549细胞对于抗癌药物VP-16的药敏性,此可为肺癌的临床治疗提供一个新的靶点。

Objective：To explore the effects of PARP inhibitor ABT-888 on the proliferation and apoptosis of A549 cells in- duced by the anti-cancer drug etoposide （VP-16）. Methods： The A549 cells were routinely euhured, and treated with VP-16 and （or） ABT-888 for 24 h. Then MTT method was employed to evaluate the proliferation of A549 cells, Flow cytometer annexin V-FITC/ PI double staining method were enrolled to analyze the apoptosis the A549 ceils, comet assay was employed to assess the DNA damage content of the A549 cells, and Western blot method was performed to analyse the distrubition of the mitochondrial-associated apoptotic factor cytochrome c in mitochondria and cytoplasm. Results： The proliferating ratios of A549 cells in VP-16 combined ABT-888 groups were significantly decreased compared to the corresponding cells in either control or VP-16 groups （P 〈 0.01 ）, and the apoptotic ratios of the A549 cells were significantly increased compared to the corresponding cells in either control or VP-16 groups （ P 〈 0.05 ）. Sim- ultaneously, the DNA damage content of A549 cells in VP-16 combined ABT-888 groups were more serious than the cotTesponding ceils in control and VP-16 groups （P 〈0.01 ）, and the cytochrome c levels in cytoplasm of the A549 cells were significantly increased com- pared to the corresponding ceils in control and VP-16 groups （ P 〈 0.01 ）. Conclusion： The PARP inhibitor ABT-888 can increase sensitivity of A549 cells in response to VP-16 through inhibiting PARP activity then blocking DNA repair. Thus provide a new target for the clinical treatment of lung cancer.