Study of SFRP1 and SFRP2 methylation status in patients with de novo Acute Myeloblastic Leukemia

INTODUCTION Acute myeloid leukemia (AML) is a heterogeneous group of hematologic malignancies with abundant changeability in the pathogenesis. DNA methylation of CpG islands within the promoters of specific genes may play roles in tumor initiation and progression. Secreted frizzled-related proteins (SFRPs) are negative regulator of the Wnt signaling pathway. In the present study, we examined the methylation status of SFRP1 and SFRP2 genes in patients with AML. METHODS Isolated DNA from peripheral blood of 43 AML patients and 25 healthy subjects as a control group was treated with sodium bisulfite was treated with sodium bisulfite and analyzed by methylation-specific polymerase chain reaction (MSP) with primers specific for methylated and unmethylated promoter sequences of the SFRP1 & -2 genes. We used Mann-Whitney u-tests to investigate the correlation between SFRP1 and SFRP2 genes hypermethylation and clinical parameters. RESULTS The frequency of aberrant hypermethylation of SFRP1 and SFRP2 genes in patients with AML was determined 30.2% (13/43) and 20.9% (9/43), respectively. In addition, for all subjects in control group, methylation of SFRP1 and SFRP2 genes were negative. Patients with M0 subtype of FAB-AML had the highest incidence of hypermethylation of SFRP1 (P = 0.028) and SFRP2 (P = 0.004). CONCLUSION The present study showed that, like many solid tumors, methylation of SFRP genes also occurs in AML. Therefore, the methylation of these genes may play a role in the initiation of leukmogenesis.