Objectives: To detect the methylation of P15INK4B gene in patients with myelodysplastic syndromes (MDS) and to investigate the demethylating effects of decitabine and arsenic trioxide (As2O3).
Methods: The bone marron mononuclear cells from 14 MDS patients were collected. The methylation of P15INK4B gene was detected with restrictive endonucleases combined with PCR technique. The peripheral blood mononuclear cells from one of the patients who had progressed into acute leukemia were treated with decitabine and As2O3 in vitro to test the change of methylation.
Results: No methylation of P15INK4B gene was detected in MDS patients with low risk of leukemia. The methylation of P15K4B gene was found in 4 MDS patients with high-risk of leukemia and 4 patients who had progressed from MDS to acute leukemia. After exposed to decitabine or As2O3, the methylation went down by 50%.
Conclusion: P15INK4B gene hypermethylation is closely associated with MDS pathogenesis. Decitabine and As2O3 have demethylating effect on the cells from the MDS patient.