Effect of 5-Aza-2′-deoxycytidine on SOCS-1 gene expression, proliferation and apoptosis in RPMI8226 cells

Objective To investigate the effect of DNA methylation inhibitor 5-Aza-2′-deoxycytidine (5-Aza-CdR) on transcription regulation of SOCS-1 gene and the molecular biological behaviors in RPMI8226 cells. Methods The RPMI8226 cells were treated with different doses of 5-Aza-CdR,and MTT was used to detect the proliferation of RPMI8226 cells. The apoptosis and cell cycle were analyzed by flow cytometry. Real-time PCR was used to examine expression of the SOCS-1 gene. Results 5-Aza-CdR significantly inhibited cell growth in dose and time dependent manners(P 0. 05). 5-Aza-CdR increased the apoptosis rate of RPMI8226 cells as well as in a dose-dependent manner. The apoptosis rates of RPMI8226 cells treated with 5-Aza-CdR at concentration of 0. 1,0. 5,1. 0,2. 0,5. 0 μmol/L for 72 hours were (29. 62 ± 2. 87)% ,(39. 98 ± 2. 53)% ,(49. 07 ± 3. 51)% ,(60. 15 ± 4. 54)and(69. 88 ± 3. 49)% respectively. After treatment with different concentrations of 5-Aza-CdR for 72 h,cells were arrested in G (0) /G (1) phase in contrast to the control group (P 0. 05). Real-time PCR results showed that there were few SOCS-1 genes expressed in RPMI8226 cells after treatmean with 5-Aza-CdR for 72 h,and expression level of SOCS-1 was increased significantly in a concentration-dependent manner(P 0. 05). Conclusion 5-Aza-CdR could narkedly inhibit the proliferation of RPMI8226 cells and induce cell apoptosis,which might be related to demethylation and reexpression of the SOCS-1 gene in RPMI8226 cells.