大黄素逆转非小细胞肺癌EGFR-TKI耐药的机制研究∗

摘要

Objective To investigate the mechanism of rheum emodin reversed resistance of epidermal growth factor receptor tyrosine kinase inhibitors(EGFR⁃TKI) in non⁃small cell lung cancer(NSCLC). Methods NSCLC cell lines resistant to EGFR⁃TKI ( HCC827/GR) was built by continuous induction method. MTS method was used to detect the ability of cell proliferation by treating HCC827 and HCC827/GR cells with rheum emodin( 30μmol/L) , gefitinib( 1μmol/L) and rheum emodin( 30μmol/L) combined with gefitinib(1μmol/L). The expressions of p⁃EGFR, p⁃AKT, p⁃ERK1/2 and p⁃MET in HCC827 and HCC827/GR cells were detected by Western blotting method. Results The proliferation ability of HCC827/GR cell was not decreased by treating gefitinib or rheum emodin monotherapy, but remarkably decreased by treating the combination of gefitinib and rheum emodin, with statistical difference( P<0�05) . The expressions of p⁃EGFR and p⁃ERK were strong and p-AKT expression was weak in HCC827 and HCC827/GR. p⁃MET expression was significantly increased in HCC827/GR compared with HCC827. After treated with 1μmol/L gefitinib, the expressions of p⁃EGFR and p⁃ERK were down⁃regulated in HCC827, and the expression of p⁃EGFR was significantly descended in HCC827/GR cell. 30μmol/L rheum emodin could obviously reduce the expression of p⁃MET in HCC827/GR. Otherwise, after treated with rheum emodin and gefitinib, the expressions of p⁃EGFR, p⁃ERK1/2 and p⁃MET were markedly inhibited. Conclusion Rheum emodin may reverse the resistance of EGFR⁃TKI in NSCLC, probably by inhibiting the activation of c⁃Met.%目的：探讨大黄素逆转非小细胞肺癌（ NSCLC）表皮生长因子受体酪氨酸激酶抑制剂（ EGFR⁃TKI）耐药的作用机制。方法应用持续诱导的方法构建NSCLC EGFR⁃TKI耐药细胞株HCC827／GR；应用MTS法检测大黄素（30μmol／L）、吉非替尼（1μmol／L）及两药联合处理HCC827和HCC827／GR细胞48h后细胞增殖能力的变化；应用Western blotting法检测HCC827和 HCC827／GR细胞中p⁃EGFR、p⁃AKT、p⁃ERK1／2及p⁃MET蛋白表达水平的变化。结果 MTS法检测结果显示，经单药吉非替尼或大黄素处理后，HCC827／GR细胞增殖能力未减弱，而两药联合处理组的细胞增殖能力明显下降，差异有统计学意义（ P＜0�05）。 Western blotting检测结果显示，HCC827、HCC827／GR细胞中p⁃EGFR、p⁃ERK1／2明显表达，而p⁃AKT表达微弱；HCC827／GR 中p⁃MET表达水平较HCC827明显上调。经单药吉非替尼处理后，HCC827细胞株p⁃EGFR、p⁃ERK1／2表达水平下调，HCC827／GR细胞株p⁃EGFR表达明显下调；大黄素可显著下调HCC827／GR细胞株p⁃MET表达，但对p⁃EGFR、p⁃ERK1／2的表达无影响；而大黄素与吉非替尼两药联用可明显抑制HCC827／GR细胞株p⁃EGFR、p⁃ERK1／2以及p⁃MET的表达。结论大黄素可以逆转NSCLC EGFR⁃TKI耐药，可能是通过抑制c⁃Met的活化来实现。