基于miRNA-206/449a探索扶正抗癌方逆转吉非替尼治疗非小细胞肺癌耐药机制

Lung cancer is one of the most common malignant tumor worldwide, the morbidity and mortality are rising year on year, the traditional therapy has reached a therapeutic plateau. The molecule targeted drug gefitinib is effective in advanced non-small cell lung cancer(NSCLC) patient with EGFR mutation, however, most patients will develop secondary resistance in 10-12 months after treatment. In previous clinical trials we found that treatment with gefitinib plus FuZhengKangAi decoction (FZKA) prolonged progression-free survival compared with gefitinib in patients with NSCLC, we also demonstrated that FZKA combined with gefitinib was superior to gefitinib on the inhibition of resistant cell line H1650, which indicated that FZKA may reverse the resistance of gefitinib. miRNA array showed that FZKA combined with gefitinib significantly up-regulated the lever of miRNA-206/449a compare with control group, FZKA or gefitinib,some researches indicated that miRNA-206/449a inhibited MET pathway, and MET amplification led to gefitinib resistance. The next step we will conduct experiment in vitro and in vivo to explore the mechanism on reversal of gefitinib resistance by FZKA base on miRNA-206/449a, to provide objective evidence on enhancement of gefitinib by FZKA and explore the effect of miRNA-206/449 on reversal of gefitinib resistance.

肺癌是全球常见的恶性肿瘤之一，其发病率及死亡率逐年上升，传统治疗手段已进入平台期，靶向药物吉非替尼治疗EGFR基因突变的晚期非小细胞肺癌疗效可，但大部分患者在10-12个月左右出现耐药。前期在临床中发现扶正抗癌方联合吉非替尼能延长晚期非小细胞肺癌患者的疾病无进展生存时间，基础研究也发现该方联合吉非替尼对耐药细胞株H1650的抑制优于吉非替尼，提示扶正抗癌方对吉非替尼有逆转耐药作用，用miRNA表达谱芯片技术处理H1650细胞移植瘤发现，与对照组、扶正抗癌方、吉非替尼组比较，扶正抗癌方联合吉非替尼能明显上调miRNA-206/449a，目前有研究发现上调miRNA-206/449a能抑制MET通路，而吉非替尼耐药与MET扩增有关。下一步我们拟基于miRNA-206/449a开展体内及体外实验进一步探讨其作用机制，为中医药增强吉非替尼疗效提供客观依据，并探讨miRNA在吉非替尼耐药的作用。

分子靶向治疗是目前针对非小细胞肺癌行之有效的方，然而耐药现象的出现是目前临床治疗中遇到的最大挑战，也是亟需解决的问题之一。本研究构建吉非替尼获得性耐药细胞株 PC9-GR，筛选出PC9-GR与亲代细胞PC9之间差异表达的miRNA，以及扶正抗癌方干预 PC9-GR后miRNA表达的改 变，从而筛选出扶正抗癌方逆转吉非替尼耐药的相关 miRNA，并从miRNA 角度入手探讨扶正抗癌方对非小细胞肺癌PC9和PC9-GR细胞株增 殖、侵袭、迁移的影响，并进一步在基因和蛋白质水平探讨其可能的分子机制。最后，研究扶正抗癌方联合吉非替尼抗肿瘤效应及可能的作用机制，从而探讨扶正抗 癌方与吉非替尼合用发挥的“增效”的协同抗肿瘤效应及可能的作用机理。结果显示，扶正抗癌方可通过下调 hsa-miR-141-3p 的表达，在体外与吉非替尼联合使用时 可在体外协同抑制 PC9 和 PC9-GR 细胞的增殖，并通过 PI3K/AKT 通路明显上调抑癌基因蛋白 PTEN 的表达，同时抑制AKT磷酸化的活化，从而促进促凋亡蛋白 Bad 磷酸化，诱导细胞凋亡。