血管内皮生长因子在六价铬诱导的肺支气管上皮细胞Beas-2B恶性转化中的作用

Role and mechanism of VEGF in chromium-induced malignant transformation of bronchial epithelial cells Beas-2B

目的:探究在六价铬[Cr(Ⅵ)]诱导的人支气管上皮细胞(human bronchial epithelial cells-2B,Beas-2B)恶性转化过程中血管内皮生长因子(vascular endothelial growth factor,VEGF)在迁移、侵袭及血管生成等方面的生物学作用及其可能机制。方法:通过对VEGF高表达的恶转细胞Cr(Ⅵ)-Beas-2B转染重组VEGF质粒和siRNA,分别上调和下调VEGF的表达,利用蛋白免疫印迹检测VEGF表达及迁移侵袭相关蛋白表达,划痕实验、Transwell实验、免疫荧光实验检测细胞迁移、侵袭等运动能力的改变,以及小管生成实验检测细胞血管生成能力的变化。结果:重组质粒过表达VEGF上调了恶转细胞中VEGF、基质金属蛋白酶-9、磷酸化黏着斑激酶和磷酸化Src蛋白的表达,下调了钙黏蛋白的表达;重组质粒过表达VEGF增强迁移、侵袭及血管生成能力;siRNA干扰处理结果相反。结论:VEGF通过影响迁移、侵袭相关蛋白的表达从而调控细胞迁移、侵袭以及血管生成,参与六价铬致癌过程。

Objective:To explore the biological role of vascular endothelial growth factor(VEGF)in migration,invasion and angiogenesis during the malignant transformation of human bronchial epithelial cells Beas-2B induced by hexavalent chromium,and to explore whether VEGF can regulate migration and invasion by influencing the expression of migration and invasion-related proteins at the protein and molecular levels.Methods:VEGF expression was up-regulated or down-regulated by recombinant VEGF overexpression plasmid and siRNA interference,respectively.And then detected the expression of VEGF and migration and invasion related proteins by western blotting,and the migration and invasion abilities were measured by wound healing,Transwell and immunofluorescence assays,and angiogenesis ability was evaluated by tube formation test.Results:Overexpression of VEGF by recombinant VEGF plasmid up-regulated the expression of VEGF,matrix metalloproteinase-9,phosphorylated activated form of focal adhesion kinase and Src protein,and down-regulated E-cadherin expression in malignant transformed cells;Overexpression of VEGF by recombinant VEGF plasmid also enhanced the migration,invasion and angiogenesis ability of malignant transformed cells;The results of siRNA interference were contrary to those of VEGF overexpression.Conclusion:By influencing the expression of migration/invasion-related proteins,VEGF regulates cell migration,invasion and angiogenesis,and participates in the carcinogenesis induced by hexavalent chromium.