Effect of apicidin on glioblastoma U87 cells and its regulation of OCT-4 gene expression

Abstract

Objective To investigate the effect of histone deacetylase inhibitor apicidin on the glioblastoma U87 cells and its regulation of OCT-4 gene expression. Methods Glioblastoma U87 cells were treated with different concentrations of apicidin, and dimethyl sulfoxide instead of apicidin was negative control. Methyl thiazolyl tetrazolium (MTT) assay was used to detect the proliferative ability of U87 cells treated by apicidin. The cell apoptosis was observed under the fluorescence microscope, and the cell cycle was detected by using flow cytometry. Reverse transcription-polymerase chain reaction and Western blot was used to detect the expression of mRNA and protein of U87 cells, respectively relative to the expression of GAPDH. Results MTT assay results showed that apicidin inhibited U87 cells proliferation in a dose-dependent and time-dependent manner, and half of the inhibitory concentration of cell proliferation at 48 h was (1.74±0.13) μmol/L. The cell proportion of U87 cells in S-phase of the negative control, 0.2, 0.5, and 1.0 μmol/L apicidin was (32.68±0.49)%, (33.73±0.76)%, (42.92±0.56)%, and (56.95±0.53)%, respectively after 48 h apicidin administration (P < 0.05), while the proportion of G1 and G2 phase cells was decreased. The karyopyknosis and other apoptotic changes were detected in U87 cells after 48 h treatment of 1.0 μmol/L apicidin under the confocal fluorescence microscope. Western blot and RT-PCR showed that the mRNA and protein relative levels of U87 cells OCT-4 were reduced after 1.0 μmol/L apicidin treatment for 48 h compared with the negative control group (mRNA: 72.44±0.00 vs. 56.66±0.23; protein: 86.59±0.19 vs. 56.04±0.15, both P < 0.01). Conclusions Apicidin can inhibit the growth of glioblastoma U87 cells, induce cell cycle arrest and apoptosis. Its mechanism may be related to the expression of OCT-4 inhibited by apicidin. Key words: Glioma; Histone deacetylases; OCT-4; Epigenomics