Frequency of P15 /INK4B CpG island methylation in AML patients

One of the common epigenetic pathways in all types of human haematopoeitic neoplasms is the hypermethylation promoter of tumor suppressor genes. It is usually associated with inactivation of the involved genes, and can be reversed using demethylating agents. The aim of this study was to evaluate the frequency of P15 promoter methylation in Iranian acute myeloid leukemia (AML) patients. Furthermore, this study examined the correlation between P15 promoter methylation and P15 expression. P15 promoter methylation has been investigated in 59 acute myeloid leukemia (AML) patients by melting curve analysis. P15 mRNA expression has been analyzed using real-time PCR technique (∆∆CT computational) to investigate the correlation between P15 expression and P15 promoter methylation. The aberrant methylation of the P15 promoter was detected in 40.7% of all patients. Regardless of the methylation pattern, 92.9% of all patients showed a decrease in expression of P15. Out of the total number of patients, 90.9% who showed methylation of P15 gene (22 of 24) and 88.5% (31 of 35) who did not, both illustrated reduction in P15 expression level. Despite the methylation of P15 at a low expression level in most of the patients, no significant difference between methylated and unmethylated groups was observed.