TO901317抑制叉头盒蛋白M1表达并影响HepG2细胞增殖

TO901317 suppresses FOXM1 expression and proliferation in HepG2 cells

目的探讨肝X受体(liver X receptors,LXR)特异性激动剂TO901317对HepG2细胞中叉头盒蛋白M1(forkhead box protein M1,FOXM1)的表达及对HepG2细胞的增殖及细胞周期的影响。方法 TO901317(终浓度分别为0.5、5μmol/L)处理HepG2细胞24 h后,采用RT-PCR和Western blot检测FOXM1 mRNA和蛋白表达情况;采用流式细胞术检测细胞周期的变化,并用CCK-8检测HepG2细胞增殖情况。结果经不同浓度的TO901317(终浓度0.5、5μmol/L)处理HepG2细胞24 h后,FOXM1 mRNA和蛋白表达呈剂量依赖性下调(P<0.05);流式细胞仪检测结果显示,对照组G1期细胞数占间期所有细胞数的百分比为(52.98±2.53)%、0.5μmol/L TO901317处理组为(61.32±2.36)%、5μmol/LTO901317处理组为(70.40±4.65)%,表明TO901317能够剂量依赖性诱导HepG2细胞G1期阻滞(P<0.05);CCK-8检测结果显示,对照组D(450)为(1.53±0.07)、0.5μmol/L TO901317处理组为(1.25±0.09)、5μmol/L TO901317处理组为(1.06±0.06),表明TO901317能够剂量依赖性抑制HepG2细胞增殖(P<0.05)。结论肝X受体诱导HepG2细胞的G1期阻滞,并且抑制该细胞的增殖,其原因之一可能由于抑制了细胞周期蛋白关键调节因子FOXM1的表达。

Objective To investigate the effect of treatment of live X receptors specific agonist TO901317 on the expression of FOXM1 and the cell cycle and proliferation in HepG2 cells.Methods HepG2 cells were treated for 24 h with DMSO and 0.5 or 5 μmol/L TO901317.RT-PCR and Western blotting was taken to detect the FOXM1 expression at mRNA and protein levels.Cell cycle analysis was examined by flow cytometry and cell proliferation was determined by cell counting kit-8（CCK-8）.Results FOXM1 mRNA and protein expression were remarkably reduced after the treatment of TO901317 at different concentrations（P0.05）.The percentage of cells at G1 stage were（61.32±2.36）% and（70.40±4.65）% respectively after 0.5 and 5 μmol/L TO901317 treatment,significantly higher than that of the control group（P0.05）.The OD value at 450 nm was 1.25±0.09 and 1.06±0.06 respectively after 0.5 and 5 μmol/L TO901317 treatment,significantly lower than the control group（1.53±0.07,P0.05）.TO901317 notablely inhibited the HepG2 cells proliferation.Conclusion TO901317 could suppress HepG2 proliferation and induce cell arrest at G1 cycle in a does-dependent manner,and it may be result from the downregulation of FOXM1,which is one of the key transcription regulators of cell cycle proteins.