Effects of 5-azacytidine on methylation state of P16，DAPK and MGMT genes in HL60 cells

Abstract:

Objective：To explore the effect of 5-azacytidine on myeloid leukemia cell lines through detecting methylation state and expression changes of P16，death associated protein kinase（DAPK） and O-6-methylguanine-DNA methyltransferase（MGMT） after 5-azacytidine treatment for acute promyelocytic leukemia cell lines（HL60 cells）. Methods：HL60 cells were cultured with 5-azacyti－dine by routine method for 48 h. Then methylation-specific PCR（MSP） and RT-PCR were respectively used to detect gene methyla－tion status and expression changes of P16，DAPKand MGMT before and after being treated with 5-azacytidine. Results：MSP showed hypermethylated P16，DAPK and MGMT genes before 5-azacytidine treatment. Complete demethylation was observed in P16 and DAPK genes and partial demethylation was observed in MGMT gene after HL60 cells being co-cultured with 5-azacytidine. Expression intensities of P16，DAPK and MGMT genes in HL60 cells before and after treatment of 5-azacytidine were （0.22±0.04） vs. （0.64±0.12），（0.36±0.08） vs. （1.27±0.09） and （0.75±0.1） vs. （1.37±0.1） respectively（P<0.05）. Conclusions：The CpG islands of P16，DAPK and MGMT genes are hypermethylated in HL60 cells. 5-azacytidine inhibits proliferation of leukemic cells by demethyla－tion of some related genes.