内皮抑素基因腺病毒联合化疗治疗小鼠Lewis肺癌

Combination of adenovirus-mediated endostatin gene and chemotherapy in treatment of Lewis lung cancer in mice

目的 :研究腺病毒介导的小鼠内皮抑素基因联合化疗对肺癌的综合治疗作用。方法 :利用病毒重组技术将内皮抑素基因克隆入增殖缺陷型腺病毒基因组中 ,构建携带内皮抑素基因的重组腺病毒 Ad- m ES,复制小鼠 L ewis肺癌的动物模型 ,随机分成 4组 ,每组 1 0只 :化疗组 ,皮下隔日注射环磷酰胺 1 5 0 mg/ kg,共 3次 ;基因治疗组 ,一次性瘤内多点注射 6× 1 0 1 0 pfu/ml的 Ad- m ES病毒纯化液 1 0 0μl;基因联合化疗组 ,Ad- m ES病毒纯化液联合环磷酰胺 ,剂量同上 ;对照组 ,以 0 .9%生理盐水1 0 0μl替代环磷酰胺。定期测量各组肿瘤体积 ,采用 Western印迹分析检测基因转导后肿瘤组织中内皮抑素的表达 ,应用免疫组化法检测肿瘤微血管密度 (MVD) ,观察内皮抑素基因对肿瘤血管生长的抑制作用。结果 :构建了表达内皮抑素的重组腺病毒载体 Ad- m ES;各治疗组荷瘤 C5 7BL / 6小鼠肿瘤生长抑制明显 ,以基因联合化疗组尤为显著 (P<0 .0 1 ) ;基因治疗组和基因联合化疗组 MVD与对照组和化疗组相比差异显著 (P<0 .0 5 )。基因治疗过程中未见明显不良反应 ,且荷瘤鼠生存期明显延长 ,以联合治疗组为著 (P<0 .0 5 )。结论 :所构建的 Ad- m ES重组腺病毒载体可有效表达具有生物学活性的内皮抑素 ;并能减少肿瘤内微血管生成、

Objective:To study the antitumor effect of combination therapy with adenoviral transfer of mouse endostatin gene and cyclophosphamide chemotherapy on mouse Lewis lung cancer.Methods:Mouse endostatin gene was cloned into repli-cation-defective adenovirus by virus recombination technology to construct Ad-mES,adenovirus vector coding mouse endo-statin gene,and then its biological activities were surveyed in vivo.Animal models of mouse Lewis lung carcinoma in C57BL/6mice were established and randomly divided into4groups(n=10):including control,chemotherapy,gene therapy,and chemotherapy+gene therapy group.Mice received cyclophosphamide150mg/kg s.c.3times a day in a21-d cycle for chemotherapy;control group received0.9%normal saline100μl.Ad-mES(6×10 9 pfu/100μl)were administrated by multi-spots intra-tumor injection to every mouse in gene therapy group and combination therapy group.The tumor sizes were mea-sured at different times points.The expression of endostatin after transfer was detected by Western blot and the microvessel density(MVD)of tumor was measured by immunohistochemical examination.Results:Higher titers of recombinant aden-oviruses(Ad-mES)were constructed.Combination therapy with Ad-mES and cyclophosphamide inhibited tumor growth(P<0.01)and prolonged mice survival time(P<0.05)significantly.Conclusion:The recombinant adenovirus can effectively ex-press biologically active mEndostatin,which can inhibit tumor growth,decrease tumor micro-blood vessels and prolong sur-vival time.The gene therapy combined with the chemotherapy have synergistic effect,laying a foundation for the study of com-bination therapy of the solid tumor.