Aurora-A高表达对食管鳞癌血管生成及血管内皮生长因子受体-2表达的影响

Effect of overexpression of Aurora-A on angiogenesis and vascular endothelial growth factor receptor-2 expression in esophageal squamous cell carcinoma

目的探讨Aurora-A高表达对食管鳞癌血管生成及血管内皮生长因子受体-2(vascular endothelial growthfactor receptor 2,VEGFR-2)表达的影响。方法将绿色荧光蛋白(green fluorescent protein,GFP)标记的Aurora-A全长表达质粒pEGFP-C1-Aurora-A转染至食管鳞癌细胞KYSE150,经G418筛选获得Aurora-A高表达的细胞株(Aurora-A高表达组),同时设空质粒pEGFP-C1转染组(阴性对照组)和未转染组作为对照。Western blot检测各组细胞中Aurora-A蛋白的表达;采用小管形成及鸡胚尿囊膜试验检测Aurora-A高表达对肿瘤血管生成的影响;免疫组化法检测Aurora-A高表达对裸鼠移植瘤中微血管密度(microvessel density,MVD)的影响;Western blot检测Aurora-A高表达对KYSE150细胞中VEGFR-2及p-VEGFR-2(Tyr1059)表达的影响。结果 Aurora-A高表达组中总Aurora-A蛋白的表达量约为阴性对照组和未转染组的2.5倍,提示Aurora-A高表达细胞系构建成功;Aurora-A高表达组生成的血管数量、MVD值和p-VEGFR-2的表达水平均显著高于阴性对照组(P<0.01)。结论 Aurora-A高表达可促进食管鳞癌中的血管生成,其机制可能与活化VEGFR-2有关。

Objective To investigate the effect of overexpression of Aurora-A on the angiogenesis and vascular endothelial growth factor receptor-2（VEGFR-2） expression in esophageal squamous cell carcinoma.Methods Recombinant plasmid pEGFP-C1-Aurora-A was transfected to esophageal squamous cell carcinoma KYSE150 cells,from which the cell strains for overexpression of Aurora-A were screened with G418,using the cells transfected with empty plasmid pEGFP-C1 and those untransfected as controls.The expressions of Aurora-A in cells of various groups were determined by Western blot.Tube formation and chorioallantoic membrane assay were performed to confirm whether Aurora-A overexpression promoted the angiogenesis of tumor.Immunohistochemical assay was used to detect the microvessel density（MVD）in xenograft tissues of nude mice.The effect of Aurora-A overexpression on the expressions of VEGFR-2 and pVEGFR-2（Tyr1059）in KYSE150 cells was determined by Western blot.Results The expression level of Aurora-A in screened cell strains for overexpression was about 2.5 times of those in the cells transfected with empty vector and untransfected,indicating successful construction of cell strains for Aurora-A overexpression.The number of blood vessels,MVD and p-VEGFR-2 expression level in the cell strains for Aurora-A overexpression were significantly higher than those in the cells transfected with empty vector（P 0.01）.Conclusion The overexpression of Aurora-A promoted the angigenesis in esophageal squamous cell carcinoma,of which the mechanism might be associated with VEGFR-2 activation.