IL-6诱导非小细胞肺癌Gefitinib耐药的作用和机制

摘要

目的：明确IL‐6诱导非小细胞肺癌（NSCLC）细胞对表皮生长因子受体酪氨酸激酶抑制剂（EGFR‐TKI）药物吉非替尼（Gefitinib）发生耐药的作用，探讨其可能机制。方法使用噻唑蓝（MTT）、划痕实验、蛋白免疫印迹法（Western blot）分别检测IL‐6处理肺腺癌细胞株PC‐9后其对Gefitinib的敏感性、细胞迁移能力、哺乳动物雷帕霉素靶蛋白（p‐mTOR）表达等的变化；构建IL‐6高表达细胞株PC‐9psb388，检测其与PC‐9相比在对Gefitinib的敏感性、细胞迁移能力、p‐mTOR蛋白表达等方面的变化；使用雷帕霉素联合IL‐6处理PC‐9、IL‐6单独处理PC‐9以及雷帕霉素单独处理PC‐9psb388，M T T检测3组细胞Gefitinib敏感性的变化；使用PC‐9、PC‐9psb388细胞构建裸鼠移植瘤模型，对比两组移植瘤大小并用免疫组织化学检测p‐mTOR蛋白和IL‐6的表达。结果 IL‐6处理 PC‐9组较未处理组对Gefitinib的敏感性显著降低，细胞迁移能力增强，p‐mTOR蛋白表达增高。 PC‐9psb388对Gefitinib的敏感性与 PC‐9相比明显降低，细胞迁移能力增强并且p‐mTOR蛋白活化增高。雷帕霉素联合IL‐6处理PC‐9组对Gefitinib的敏感性较IL‐6单独处理 PC‐9组升高，p‐mTOR蛋白表达降低。同样雷帕霉素处理PC‐9psb388组对Ge‐fitinib的敏感性较未处理组增高，且p‐mTOR蛋白活化降低。在动物实验中，PC‐9psb388组裸鼠移植瘤体积明显大于 PC‐9组，检测移植瘤组织中IL‐6和p‐mTOR蛋白的表达发现，PC‐9psb388组显著高于PC‐9组。结论 IL‐6可能通过活化p‐mTOR蛋白诱导非小细胞肺癌发生EGFR‐TKI耐药。%Objective To evaluate the effect and mechanism of IL‐6 induced Gefitinib resistance in non small cell lung cancer (NSCLC) .Methods The sensitivity of cells to Gefitinib ,the invasion ability of cells and the expression of phosphorylated p‐mTOR was assessed by MTT assay ,Transwell assay and Western blot ,respectively .PC‐9psb388 stable over expressing human recombi‐nant IL‐6(hrIL‐6) cell line was established by transfecting PC‐9 cells with a lentivirus psb388 expressing IL‐6 and stable transfecta‐nts over‐expressing IL‐6 in human lung cancer cell line PC‐9 .The sensitivity of cells to Gefitinib ,the invasion ability ,expression of p‐mTOR were then detected .PC‐9/PC‐9psb388 xenografts were established and the expression of p‐mTOR and IL‐6 in tumor sec‐tions were then detected .Results The sensitivity of PC‐9 cells to Gefitinib was reduced by IL‐6 ,the invasion ability of PC‐9 cells and the expression of p‐mTOR was significantly increased with IL‐6 treatment .The sensitivity of PC‐9 cells to Gefitinib was promi‐nent higher in PC‐9psb388 cells ,while the invasion ability of PC‐9psb388 cells and the expression of p‐mTOR was higher than PC‐9 cells .The sensitivity to Gefitinib was improved and expression of p‐mTOR reduced in rapamycin‐treated PC‐9psb388 cells and IL‐6 stimulated PC‐9 cells .Tumor volume of PC‐9psb388 xenografts was significantly higher than that of PC‐9 cells .The expression of p‐mTOR and IL‐6 in tumor sections of PC‐9psb388 group were higher than that of PC‐9 group .Conclusion IL‐6 could elevate the expression of p‐mTOR to induce Gefitinib resistance in non small cell lung cancer (NSCLC) .