洛伐他汀克服非小细胞肺癌PC9细胞株吉非替尼耐药的体外研究

Lovastatin overcomes gefitinib resistance in human non-small cell lung cancer cell line PC9 in vitro

目的:研究联合洛伐他汀(lovastatin)和吉非替尼(gefi tinib)对体外诱导吉非替尼获得性耐药的非小细胞肺癌细胞株PC9细胞凋亡以及相关蛋白表达的影响,并探讨其可能的机制。方法:应用洛伐他汀联合吉非替尼处理耐吉非替尼的非小细胞肺癌PC9细胞株后,采用WST-1法检测不同药物处理对PC9细胞增殖的影响,Hoechst33342荧光染色法观察细胞凋亡形态,FCM法观察细胞凋亡状况,蛋白质印迹法检测凋亡相关蛋白的表达水平。结果:洛伐他汀联合吉非替尼可在体外诱导耐吉非替尼的PC9细胞凋亡,抑制其细胞增殖;洛伐他汀联合吉非替尼可诱导耐吉非替尼的PC9细胞中磷酸化表皮生长因子受体(phosphorylated epidermal growth factor receptor,p-EGFR)、磷酸化蛋白激酶B(phosphorylated protein kinase B,p-AKT)和磷酸化细胞外调节蛋白激酶1/2(phosphorylated extracellular signal-regulated kinase1/2,p-ERK1/2)蛋白表达水平明显下调。结论:在体外诱导吉非替尼获得性耐药的非小细胞肺癌细胞株PC9中,洛伐他汀可以克服吉非替尼耐药,两者具有良好的协同作用,提示两药联合对于出现吉非替尼耐药的非小细胞肺癌的临床治疗可能具有很大的应用潜力。

Objective： To investigate the effects of lovastatin combined with gefitinib on the apoptosis and the expressions of apoptosis-related proteins of non-small cell lung cancer cell line PC9, which was induced by gefitinib in vitro to acquire drug resistance, as well as to explore the possible mechanism. Methods： Lovastatin combined with gefitinib was applied to treat the PC9 cells with acquired gefitinib-resistance. Then the proliferation of PC9 cells treated with different drugs was detected by WST-1 method. The morphology of apoptosis was observed under an inverted phase contrast microscope after Hoechst33342 staining. Apoptosis rates in different treatment groups were detected by flow cytometry （FCM）. The expressions of apoptosis-related proteins were detected by Western blotting. Results： Lovastatin combined with gefitinib could induce apoptosis of PC9 cells with acquired gefitinib-resistance in vitro. The expressions of phosphorylated epidermal growth factor receptor （p-EGFR）, phosphorylated protein kinase B （p-AKT） and phosphorylated extracellular signal-regulated kinase （p-ERK） were significantly decreased by combination of lovastain and gefitinib. Conclusion： For non-small cell lung cancer cell line PC9 with acquired drug-resistance which is induced by gefitinib in vitro, lovastatin can overcome gefitinib-resistance. The combination of both drugs shows a great synergistic effect, suggesting that the combination treatment of lovastatin and gefitinib may have great considerable clinical potential in non-small cell lung cancer with gefitinib-resistance.