自噬与非小细胞肺癌对吉非替尼耐药关系的实验研究

目的:探讨细胞自噬与非小细胞肺癌对Gefitinib耐药的相关性,寻找逆转非小细胞肺癌对Gefitinib耐药的新靶点。方法:以体外培养的人非小细胞肺癌Gefitinib敏感细胞PC-9与Gefitinib耐药细胞PC-9/GR为研究对象,通过MTT法检测Gefitinib对PC-9及PC-9/GR细胞存活率的影响;Western blot检测Gefitinib对PC-9及PC-9/GR细胞中自噬相关蛋白LC3的表达的影响;流式细胞术检测自噬诱导剂雷帕霉素和Gefitinib对PC-9/GR细胞凋亡率的影响。结果:PC-9/GR细胞Gefitinib IC50为PC-9细胞的200倍以上,具有非常明显的耐药性。PC-9/GR细胞中LC3II的表达显著低于PC-9/GR细胞(P0.05)。Rapamycin联合Gefitinib作用于PC-9/GR细胞可以明显提高其细胞凋亡率(P0.05)。结论:细胞自噬减弱与非小细胞肺癌对Gefitinib耐药有关,诱导细胞自噬可能逆转非小细胞肺癌对Gefitinib耐药。

Study on the Correlation of Autophagy with Gefitinib Resistance of Non-small-cell Lung Cancer

Objective:To explore the correlation of autophagy with gefitinib resistance of non-small-cell lung cancer andinvestigate a novel approach to reverse drug resistance.Methods:Gefitinib-sensitive cell line PC-9 and Gefitinib-resistant cell linePC-9/GR were cultured in vitro. MTT assay was applied to test the cell viabilities of PC-9 and PC-9/GR cells after gefitinib treatment.Western blot analysis was used to determine the expression of autophagy related protein LC3. Flow cytometry was also used to measurethe apoptosis after rapamycin and/or gefitinib treatments.Results:The IC50 of PC-9/GR cells was 200-fold higher than that of PC-9 cells.PC-9/GR cells were obviously resistant to gefitinib. The expression of LC3 protein in PC-9/GR cells was significantly lower than that ofPC-9 cells. Induction of autophagy by rapamycin reversed resistance and promoted the apoptosis in PC-9/GR cells.Conclusion:Thedecrease of autophagy was associated with gefitinib resistance in lung cancer, induction of autophagy might be a novel approach toreverse gefitinib resistance.