ABSTRACT
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<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<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.