中文摘要：

目的：观察恩度联合放疗对Lewis肺癌的生长抑制作用，检测肿瘤中微血管密度（ MVD）及αvβ3 mRNA的表达，探讨其在肿瘤血管“正常化”及协同抑瘤作用中的可能机制。方法荷瘤小鼠随机分成4组：空白对照组（NC），恩度组（ES），放射治疗组（RT），恩度联合放疗组（ES＋RT）。从开始治疗后隔日测量肿瘤体积，绘制生长曲线。免疫组化法及RT-PCR分别检测各组肿瘤组织中MVD及αvβ3 mR-NA的表达情况。结果（1）ES＋RT组的抑瘤作用最为明显；（2）与空白对照组相比，RT组随时间延长微血管计数逐渐增加，ES组及ES＋RT组下降，其中ES＋RT组比ES组下降更为明显，差异有统计学意义（P＜0．05）；（3）与空白对照组相比，RT组αvβ3 mRNA表达水平升高，而ES及ES＋RT组则降低，ES＋RT组降低更为明显，ES组在第6天扩增倍数最低，各治疗组在d8～d12均有统计学差异（ P＜0．05）。结论恩度联合放疗显著抑制Lewis肿瘤的生长；恩度能使肿瘤MVD明显减少，形态趋于正常；恩度可下调αvβ3 mRNA的表达，改善肿瘤组织紊乱的血管网，降低乏氧，可能是放疗增敏的机制之一。

英文摘要：

Objective To observe the MVD and integrin αvβ3 mRNA expression changes in tumor -bearing rats by using endostar combined with radiotherapy ,and to explore the potential synergy mechanism .Meth-ods We randomly divided the tumor -bearing rats into four groups：control group（NC）,endostar group（ES）, radiation treatment group （ RT） and endostar combined radiotherapy group （ ES ＋RT） .Tumor inhibition rate was calculated every other day .Microvessel density and αvβ3mRNA were texted by immunohistochemical or real time PCR in each group.Results （1）ES＋RT group showed the most obvious inhibition rate;（2）Compared with NC group,microvessel density of RT was increased ,but decreased in ES group and ES ＋RT group significantly （ P＆lt;0.05）;（3）Compared with NC group,αvβ3 mRNA expression of RT group was increased,while decreased in ES group and ES＋RT group,and ES ＋RT group displayed a greater decrease when compared to ES group （ P＆lt;0.05）.Conclusion Endostar combined radiotherapy can inhibit the growth of cancer and the expression ofαvβ3mRNA,improve the disorders of tumor vascular network .It may be one of the mechanisms of increasing radi-osensitization.