Methylation of p15INK4b and E-cadherin genes is independently correlated with poor prognosis in acute myeloid leukemia

Abstract Hypermethylation of CpG islands is a common mechanism by which tumor suppressor genes are inactivated. The tumor suppressor gene p15 INK4b is important component of cell cycles, whereas E-cadherin gene is often termed a metastasis suppressor gene. We have studied the feasibility of detecting tumor-associated aberrant p15 INK4b and E-cadherin methylation in acute myeloid leukemia (AML) using methylation-specific PCR. Aberrant methylation of p15 INK4b was detected in 31 of 61 (51%) AML patients. On the other hand, E-cadherin hypermethylation was detected in 36 of 61 (56%) AML patients. We have examined the methylation pattern of these genes and the prognosis in AML patients using a log-rank test. Methylation of p15 INK4b gene significantly correlated with prognosis ( p  = 0.0012), and methylation of E-cadherin gene more significantly correlated with prognosis ( p  = 0.0004). When both were methylated, there was even more significant unfavorable prognosis compared to either of the methylated genes ( p INK4b and E-cadherin genes can provide clinically important evidence on which to base treatment.