Effect of 5-Aza-CdR on biological activity and inhibitor of DNA binding 4 gene expression in human erythroleukemia cell line K562 / 中国实验血液学杂志

ABSTRACT

This study was aimed to investigate the effect of 5-Aza-CdR on the biological activity of human erythroleukemia cell line K562 and the expression of inhibitor of DNA binding 4 (ID4). ID4 methylation in K562 cell line was detected by methylation-specific PCR. RQ-PCR was used to analyze the expression levels of ID4 mRNA in K562 cell line treated by different concentrations of 5-Aza-CdR. Cell apoptosis rate and cell cycle were analyzed by flow cytometry. The result showed that ID4 gene methylation existed in K562 cells, ID4 mRNA expression in K562 cells treated with 5-Aza-CdR increased in a concentration-dependent manner, the difference between experimental groups was statistical significant (p < 0.01). The 5-Aza-CdR could enhance the apoptotic rate of K562 cells in time and dose-dependent manner, the apoptotic rate of K562 cells highly correlated to relative expression level of ID4 mRNA (r = 0.95). After the K562 cells were treated by 5-Aza-CdR for 48 hours, cells in G(0)/G(1) phase increased, cells in G(2)/M phase decreased along with enhancement of drug concentration. It is concluded that methyltransferase inhibitor 5-Aza-CdR can re-express the silent ID4 gene in K562 cells. The upregulation of ID4 may be a key factor to give rise to cell apoptosis, and the cell cycle of K562 cells can be arrested by 5-Aza-CdR.