奥希替尼联合贝伐珠单抗治疗伴EGFR T790M突变肺腺癌的疗效与机制研究  

Effect of osimertinib combined bevacizumab on lung adenocarcinoma with EGFR T790M mutation and its mechanisms

作　　者：熊志成[1] 刘洋[1] 孙鑫[1] 马洁韬[1] 张树玲[1] 孙丽[1] 孙婧[1] 张晓诺[1] 韩琤波[1] 

机构地区：[1]中国医科大学附属盛京医院第一肿瘤科,沈阳市110022

出　　处：《中国肿瘤临床》2017年第15期744-749,共6页Chinese Journal of Clinical Oncology

基　　金：辽宁省高等学校杰出青年学者成长计划项目(编号:LJQ2014082)资助~~

摘　　要：目的:通过移植瘤动物实验探讨奥希替尼联合抗VEGF单克隆抗体靶向药物贝伐珠单抗的疗效及作用机制,为进一步临床试验提供理论依据。方法:构建EGFR T790M突变的H1975人肺腺癌细胞移植瘤动物模型。实验分组:低剂量奥希替尼组、高剂量奥希替尼组、低剂量奥希替尼联合贝伐珠单抗组、高剂量奥希替尼联合贝伐珠单抗组。每组各5只小鼠,给药方法:奥希替尼2.5 mg/kg/d或5 mg/kg/d,采用每天灌胃处理;贝伐珠单抗5 mg/kg,每周2次腹腔注射。接种后和给药期间绘制肿瘤生长曲线,给药2周后处死裸鼠,活检整个肿瘤。免疫组织化学SP法检测肿瘤HIF-1α、VEGF和微血管密度(microvessel density,MVD)。应用Western blot法检测EGFR及其下游AKT和ERK信号通路蛋白的表达。结果:给药2周后,高剂量奥希替尼单药组较低剂量奥希替尼单药组肿瘤体积明显缩小,HIF-1α、VEGF表达率和MVD显著降低(P<0.05),p-EGFR、p-AKT和p-ERK表达减少(P<0.05)。低剂量奥希替尼联合贝伐珠单抗组肿瘤体积明显小于低剂量奥希替尼单药组(P<0.05),上述因子均明显降低(P<0.05)。低剂量奥希替尼联合组与高剂量奥希替尼单药组比较,肿瘤体积差异无统计学意义(P=0.178),p-EGFR、p-AKT、p-ERK表达差异无统计学意义(P>0.05)。高剂量奥希替尼联合组与高剂量奥希替尼单药组体积差异无统计学意义(P=0.642)。两个联合组之间,体积差异均无统计学意义(P=0.072),上述因子表达差异均无统计学意义(P>0.05)。结论:贝伐珠单抗能够显著增加奥希替尼对伴EGFR T790M突变的肺腺癌移植瘤的杀伤能力。贝伐珠单抗与奥希替尼协同作用是通过降低肿瘤中VEGF表达,改善肿瘤微环境,增强抑制EGFR下游信号通路激活而实现的。Objective：This study was performed using preclinical transplanted animal experiments to analyce the effects and mechanisms of third-generation EGFR-TKIs combined with anti-angiogenic therapy,thereby providing theoretical basis for further clinical trials.Methods：Researchers constructed the transplant BALB/C nude mice models with H1975 lung adenocarcinoma cell line（EGFR T790M） and divided the mice into four groups and treated them with osimertinib（2.5 or 5 mg/kg/day,gavage） alone or plus bevacizumab（5 mg/kg/twice weekly,i.p.） when the tumors reached approximately 0.4-0.6 cm^3 in volume.The tumor growth curve of tumor volume was drawn according to the time in every group.After 2 weeks of treatment,the mice were killed and the tumors were processed for immunohistochemical staining and Western blot analysis.Immunostaining was performed to detect：HIF-1α,VEGF,and microvessel density（MVD） by using SP method on paraffin sections.Western blot analysis was used to analyze the protein expression levels of EGFR,AKT,and ERK signal transduction pathways.Results：After 2 weeks of treatment in high-and low-dose osimertinib alone,tumor volume in the high-dose group was significantly less than in low-dose osimertinib-alone group（P〈0.05）.VEGF,HIF-1α expression,and MVD were significantly low in the high-dose osimertinibalone group（P〈0.05）.Increasing doses of osimertinib induced dose-dependent weakening of the p-EGFR,p-AKT,and p-ERK expression levels（P〈0.05）.In the low-dose osimertinib-plus-bevacizumab group and low-dose osimertinib-alone group,no significant difference in tumor volume and the above factors was observed.In the low-dose osimertinib-plus-bevacizumab group and high-dose osimertinib-alone group,tumor volumes did not exhibit significant difference（P=0.178）.Moreover,VEGF,HIF-1α expression,and MVD exhibited no significant difference.No significant difference in the p-EGFR,p-AKT,and p-ERK expression levels was found between high-dose osimertinib-alone group and low-dose osimert

关 键 词：非小细胞肺癌 表皮生长因子受体 酪氨酸激酶抑制剂 抗血管生成治疗 肿瘤微环境 

分 类 号：R734.2[医药卫生—肿瘤]