OBJECTIVETo investigate the clinical significance of promoter methylation status of hPer3 gene in acute myeloid leukemia (AML) patients and the in vitro effect of decitabine (DCA) on AML cell lines HL-60 and U937.

METHODSThe promoter methylation status of hPer3 gene and mRNA expression levels in bone marrow of 206 AML and 40 iron deficiency anemia (IDA) patients (as control) were detected by methylation specific PCR (MS-PCR) and real-time PCR (RT-PCR). The HL-60 and U937 cell lines were treated with different concentrations of DCA for 48 and 72 h. The inhibition rates of cell proliferation were detected by methyl thiazolyl tetrazolium (MTT); the early apoptosis rates by staining with Annexin V and PI; the CD14 and CD11b expressions by flow cytometry (FCM); the promoter methylation status of hPer3 gene by MS-PCR; and the hPer3 mRNA expressions levels by RT-PCR.

RESULTSThe promoter methylation rates of hPer3 in newly diagnosed (ND) group, partial remission(PR) group, complete remission (CR) group, relapse (R) group and control group were 93.65% (59/63), 54.39% (31/57), 24.66% (18/73), 61.54% (8/13) and 0% (0/40), and the hPer3 mRNA expression levels were 0.19 ± 0.08, 6.28 ± 2.11, 52.76 ± 14.17, 8.18 ± 4.36, 75.03 ± 18.16, respectively. There was a significant statistic difference between any two group (P < 0.01) excepting for between PR and R group (P > 0.05). After DCA treatment, the promoter hypermethylation status of hPer3 was reduced and the mRNA and CD14, CD11b expression levels were up regulated in a dose dependent manner with an induction of cell apoptosis.

CONCLUSIONSPromotor methylation status and mRNA expression of hPer3 gene may be indicators for evaluating AML. DCA can induce the expression of hPer3 gene and cells apoptosis in AML.