Aberrant methylation of CCAAT/enhancer binding protein zeta promoter in acute myeloid leukemia.

The aberrant changes of tumor suppressor genes (TSGs) are now recognized as an important mechanism contributing to the development of acute myeloid leukemia (AML). CCAAT/enhancer binding protein zeta (C/EBPζ), a candidate TSG, has been found to be involved in cancers including AML. We detected the methylation status of C/EBPζ promoter in 133 patients with AML using the methylation-specific polymerase chain reaction (MS-PCR) and examined C/EBPζ transcript in 32 patients using real-time quantitative PCR. The abnormal methylation of C/EBPζ gene promoter was found in 62 (46.6%) AML cases. No correlation was found between C/EBPζ promoter hypermethylation and the age, sex, WBC counts, platelet counts and FAB subtypes of AML patients (P>0.05). The trend that the frequency of C/EBPζ methylation increased as karyotype became more adverse was observed (R=0.167, P=0.075). There was a significant correlation between C/EBPζ expression and C/EBPζ methylation in AML patients (R=0.606, P=0.002). Our data suggest that the aberrant methylation of C/EBPζ promoter may be involved in AML.