人脑胶质瘤细胞中β-catenin/Tcf-4转录对AKT2基因表达的调控及对其生物学行为影响

Effect of Transcription of β-catenin/Tcf-4on Expression of AKT2 Gene and Biological Behavior of Human Brain Glioma Cells

目的研究人脑胶质瘤细胞中β-catenin/Tcf4转录对AKT2基因表达的调控及对其生物学行为的影响。方法通过荧光素酶实验以及CHIP-PCR实验确立砰4(属于AKT2启动子区)的结合活性以及具体结合位点。使用阿司匹林恢复AKT2基因的表达以及阻断B-catenin/Tcf-4转录复合物活性,之后使用流式细胞术检测细胞的周期,最后使用Transwell实验检测细胞侵袭能力以及Annexin V检测细胞的凋亡情况。结果AKT2的引物1和引物2之间的某个区域存在结合位点,能够与Tcf-4直接结合进而调控AKT2的转录与表达:Tcf-4主要是通过位点2而调控AKT2基因的转录与表达;AKT2能恢复ASA引起的细胞周期的阻滞,使细胞进入S期;Transwell结果显示,对照组细胞的侵袭力较ASA组细胞的侵袭力高,且ASA组细胞的侵袭力较ASA+AKT2组低。结论B-eatenin/Tcf-4转录复合物以直接转录的方式调控AKT2的表达,进而促进胶质瘤细胞的增殖能力以及侵袭能力。

Objective To analyze the effect of transcription of β-CATENIN/Tcf-4on expression of AKT2gene and biological behavior of human brain glioma cells.Methods We used the luciferase experiment and CHIP-PCR experiment to determine the activity and specific binding sites of Tcf-4(the union of AKT2promoter region).And we applied aspirin to restore AKT2 gene expression and block activity of β-eatenin/Tcf-4transcription complex.The cell cycle was measured by flow cytometry.Finally we used the Transwell experiments to detect cell invasion ability and Annexin V to detect cell apoptosis.Results A binding site existed between primer 1and primer 2of AKT2.This site could be directly combined with Tcf4.Tcf-4mainly regulated the transcription and expression of AKT2gene through site 2.AKT2could restore cell cycle block caused by ASA and make the cells enter S phase.Transwell results showed the call invasiveness was higher in the control group than in the ASA group,and the cell invasiveness was lower in the ASA group than in the ASA +AKT2 group.Conclusion The transcription complex of β-eatenin/Tcf-4regulates the expression of AKT2 by means of direct transcription,thus promotes the proliferation and invasiveness of glioma cells.