Foxg1抑制肝癌细胞血管形成及其机制

目的 通过干扰和过表达肝癌细胞中的Foxg1,探讨Foxg1对人脐静脉血管内皮细胞(human umbilical vein endothelial cells,HUVEC)血管生成能力的影响及其机制.方法 实验分为Hep3B干扰组、Hep3B对照组、Huh7过表达组和Huh7对照组,提取各组细胞条件培养基(conditional medium,CM);通过Transwell实验、管腔形成实验观察各组CM对HUVEC的迁移及管腔形成的影响;采用实时荧光定量PCR(RT-PCR)及Western blot检测血管内皮生长因子A(vascular endothelial growth factor A,VEGFA)在各组肝癌细胞中的mRNA及蛋白水平,酶联免疫吸附实验(ELISA)检测各组CM内VEGFA浓度;采用Western blot检测4组肝癌细胞AKT1、p-AKT1的蛋白水平.结果 Hep3B干扰组较Hep3B对照组CM的作用下,HUVEC细胞的迁移数显著增多(P＜0.01),Huh7过表达组较Huh7对照组CM的作用下,HUVEC细胞迁移数显著减少(P＜0.01);Hep3B干扰组CM的作用下,HUVEC细胞管腔形成数多于Hep3B对照组CM(P＜0.01),而Huh7过表达组CM的作用下,HUVEC细胞管腔形成数少于Huh7对照组CM(P＜0.01);Hep3B干扰组较Hep3B对照组VEGFA水平上调,Huh7过表达组较Huh7对照组VEGFA水平下调;Hep3B干扰组CM较Hep3B对照组CM的VEGFA水平上调,Huh7过表达组CM较Huh7对照组CM的VEGFA水平下调(P＜0.01);Hep3B干扰组较Hep3B对照组AKT1磷酸化水平升高,Huh7过表达组较Huh7对照组AKT1磷酸化水平降低.结论 Foxg1抑制肝癌血管生成的过程可能是通过抑制PI3K/Akt通路的激活下调VEGFA的表达来实现的.

Foxg1 inhibits angiogenesis in hepatocellular carcinoma in vitro

Objective To investigate the effect of forkhead box G1 (Foxg1) on the angiogenesis of human umbilical vein endothelial cells(HUVECs) by interfering and overexpressing Foxg1 in hepatoma cells,and explore its underlying mechanisms.Methods The hepatocellular carcinoma cell lines Hep3 B and Huh7 were used in this experiment,and after corresponding transfection,the cells were divided into 4 groups,that is,Hep3B shFoxg1 group (Foxg1 silence),Hep3B control group,Huh7 expFog1 group (Foxg1 overexpression) and Huh7 control group.After the HUVECs were treated with the conditioned mediums (CM) from the above 4 groups of cells,transwell assay and tube formation assay were used to observe the effect of CM on migration and tube formation of HUVECs.The mRNA and protein levels of vascular endothelial growth factor A (VEGFA) in each group were measured by real-time fluorescence quantitative PCR (RT-PCR) and Western blotting.The concentration of VEGFA in the CM was detected by enzyme-linked immunosorbent assay (ELISA).Finally,Western blotting was used to detect the protein levels of AKT1 and p-AKT1 in the 4 groups of cells.Results The number of cell migration was significantly larger in the HUVECs exposure to CM from the Hep3B shFoxg1 group than that from Hep3B control group (P ＜ 0.01),while the number was smaller in the HUVECs treated with Huh7 expFoxg1 group CM than with Huh7 control group CM(P ＜ 0.01).The CM from the Hep3B shFoxg1 group promoted tube formation in HUVECs when compared with the CM from the Hep3B control group (P ＜0.01),and the CM of the Huh7 expFoxg1 group induced less formation than the CM from the Huh7 control group(P ＜ 0.01).RT-PCR and Western blotting showed that the VEGFA level was higher in the Hep3B shFoxg1 group than the Hep3B control group (P ＜ 0.01),and that in the Huh7 expFoxg1 group was down-regulated than the Huh7 control group (P ＜ 0.01).Western blot analysis showed that the Hep3B shFoxg1 group had enhanced phosphorylation of AKT1 than the Hep3B control group,while the level was opposite in the Huh7 expFoxg1 group than the Huh7 control group.Conclusion Foxg1 inhibits the angiogenesis of hepatocellular carcinoma,which may be through suppressing the PI3K/AKT pathway and down-regulating the expression of VEGFA.