VEGF高表达的胶质瘤细胞对体外共培养微血管内皮细胞的作用

目的以VEGF阴性表达的正常鼠肝细胞系BRL3A为对照 ,研究VEGF高表达的恶性胶质瘤细胞系C6对体外共培养的肺微血管内皮细胞的作用。方法建立体外C6 ,BRL3A与微血管内皮细胞共培养方法 ,观察不同培养体系中内皮细胞活体形态的改变、毛细血管管腔样结构形成的数量、用生长曲线和流式细胞仪观察内皮细胞的增殖状况 ;利用免疫细胞化学的方法检测共培养后的内皮细胞上和血管新生有关的生长因子和受体的表达变化。结果发现与胶质瘤细胞C6共培养时 ,可引起内皮细胞的增殖速度加快 ,细胞周期中S期和G2-M期百分率与对照组相比明显增加(P<0.05),内皮细胞呈现大量的毛细血管管腔样结构 ;而与BRL3A共培养内皮细胞呈现相对静止的状态(P<0.01) ,未观察到形态学的明显变化。免疫细胞化学结果显示与C6共培养的内皮细胞Flk_1、Flt_1蛋白表达增加(P<0.05) ,而与BRL3A共培养的内皮细胞Flk_1、Flt_1蛋白表达下降(P<0.01)。结论胶质瘤细胞C6可使共培养的肺微血管内皮细胞转化为血管新生活跃的状态 ,其可能原因为C6合成分泌的VEGF上调Flk_1、Flt_1的表达。

Effects of VEGF Over-expressed C6 Glioma Cells on Cocultured Microvascular Endothelial Cells

Objective To study the effects of VEGF over_expressed C6 glioma cell line on cocultured microvascular endothelial cells using the VEGF negative_expressed rat hepatic cells BRL 3A as control.Methods A cocultured system of C6_endotheliaI cells and BRL 3A_endothelial cells was established. The morphological changes of cocultured endothelial cells were discovered. The proliferation of endothelial cells in cocultured system was observed by cell growth curve and flow cytometry. To investigate the expression of growth factor and its receptor related to angiogenesis on cocultured endothelial cells by immunocytochemistry.Results Cocultured with C6, the endothelial cells had high proliferation rate and exhibited a tube_like morphology, while cocuItured with BRL 3A,the endothelial cells exhibited a quiescent state. Endothelial cells showed up_regulated expression of Flk_1 and Flt_1 protein(P<0.05).Conclusions C6 glioma cells can induce the cocultured endothelial cells to exhibit angiogenetic morphology, while rat hepatic cells BRL 3A have no such effect. It's possible mechanism is that the VEGF secreted by C6 up_regulates the expression of Flt_1 and Flk_1.