Effect of histone deacetylase inhibitor apicidin on biological activity of glioma stem cells via down-regulating Nanog expression

Abstract

Objective To investigate the effect ofhistone deacetylase inhibitor apicidin induced Nanog repression on proliferation,migration and invasion of glioma stem cells (GSCs).Methods GSCs were isolated from glioma cell line U87 and cultured in simplified serum-free neural stem cell medium by nanosphere suspension culture method,and purified continuously through the monoclonal formation experiment.The immunofluorescence staining of cells was employed to detect the CD133 and Nestin expressions to identify GSCs.Apicidin treatment group (GSCs treated with 0.5 μmol/L apicidin for 48 h) and blank control group were employed.Nanog mRNA and protein expressions were detected by real time-PCR and Western blotting,respectively.Double immunofluorescence staining was used to detect the co-expressions ofNanog/CD133.MTT assay was used to detect the proliferation modification of GSCs,while migration and invasion of GSCs were detected by Transwell migration and invasion assay after 0.2,0.5,1.0 and 2.0 μg/mL apicidin of treatment.Results GSCs were isolated,cultured and purified from glioblastoma cell line U87; as compared with those in the blank control group,the mRNA and protein expressions of Nanog were significantly repressed and Nanog+,CD133+ and Nanog+/CD133+ cells were obviously reduced in the apicidin treatment group (P＜0.05).The migration and invasion in the apicidin treatment group were inhibited dramatically as compared with those in the blank control group (cell number of migration:[87.50±4.65]/field vs.[128.50±6.14]/field; cell number of transmembrane:[55.75±4.79]/field vs.[81.50±5.45]/field,P＜0.05).MTT assay indicated that the absorbance value of the apicidin treatment group was significantly lower as compared with that in the blank control group (P＜0.05); the higher the apicidin concentration,the lower the absorbance value and the more obvious the proliferation inhibition.Conclusion Histone deacetylase inhibitor apicidin could inhibit the mRNA and protein expressions of Nanog,and sequentially repress the proliferation,migration and invasion of GSCs. Key words: Histone deacetylase inhibitor; Nanog; Glioma; Glioma stem cell