抑制自噬促进培美曲塞对A549细胞的增殖抑制作用

Autophagy inhibition facilitates the anti-proliferative effect of pemetrexed on A549 cells

目的研究培美曲塞对肺癌细胞A549自噬的作用及自噬的功能。方法采用MTS法观察培美曲塞对A549细胞的增殖抑制作用;采用透射电镜和免疫印迹观察培美曲塞对A549细胞自噬体和自噬相关蛋白的影响;采用自噬抑制剂CQ抑制自噬后观察培美曲塞对A549细胞的抑制作用。结果培美曲塞抑制A549细胞的增殖;培美曲塞诱导A549细胞自噬体表达增加,并诱导自噬相关蛋白Beclin-1表达和LC3-Ⅰ向LC3-Ⅱ的转换增加,p62表达降低;自噬抑制剂CQ提高培美曲塞对A549细胞抑制作用,使培美曲塞单药组的抑制率由(28.42±2.45)%增加到CQ联合培美曲塞组的(45.36±3.52)%。结论培美曲塞可以诱导肺癌细胞A549自噬增加,抑制自噬提高培美曲塞对A549细胞的增殖抑制作用,为肺癌的临床治疗提供新的联合治疗方案。

Aim To explore the effect of pemetrexed on autophagy and the function of autohpagy activation in A549 cells.Methods The anti-proliferative effect of pemetrexed on A549 cells was detected by MTS. The formation of autophagosome was observed by trans-mission electron microscopy （TEM）and the expression of autophagy-related proteins was determined by West-ern blot.The inhibitory effects of the combination of pemetrexed and a selective autophagy inhibitor on A549 cells were measured by MTS.Results Peme-trexed inhibited the proliferation of A549 cells.Auto-phagy was activated in A549 cells by exposure to pemtrexed.Autophagosome was increased in peme-trexed treatment cells compared with control group. Pemtrexed treatment led to the formation of autophago-some and the conversion of LC3-Ⅰto LC3-Ⅱ.The in-crease of Beclin-1 and the decline of autophagy sub-strate of p62 were observed in pemtrexed treated A549 cells.The pharmacological autophagy inhibitor chloro-quine （CQ）sensitized A549 cells to pemetrexed treat-ment.The inhibitory rate was （28.42 ±2.45 ）% for pemetrexed only,and （45 .36 ±3.52 ）% for peme-trexed combined with CQ.Conclusions Pemetrexed could activate autophagy in A549 cell lines.The dis-ruption of autophagy facilitates the anti-proliferative effect of pemetrexed on A549 cells,which provides a novel strategy in lung cancer treatment.