Prevalence and Clinical Significance of p15 Methylation in Acute Leukemia

Huh, Jungwon; Chung, Whasoon

Abstract

BACKGROUND
CpG islands' methylation of p15 promoter region is associated with inactivation of the p15 gene, which negatively regulates the cell cycle. We investigated the prevalence and prog-nostic significance of p15 gene methylation in AML and ALL patients, and sequentially analyzed p15 methylation during the follow-up. METHODS: This study included 52 and 25 bone marrow aspirates from 33 AML and 22 ALL patients, respectively; p15 methylation was analyzed by methylation specific PCR. RESULTS: The methylation of the p15 gene was observed in 57% of newly diagnosed AML, 70% of relapsed AML, and 23% of newly diagnosed ALL patients. Moreover, p15 methylation was found in 65% of AML and 33% of ALL patients with a normal karyotype. No association was found between p15 methylation status and prognostic factors or clinical outcomes; however, p15 methylation status correlated well with the clinical and pathologic features of disease status during the follow-up. CONCLUSIONS: The methylation of the p15 gene may be of use as a marker for disease monitoring of acute myelogeneous leukemia, especially in patients with a normal karyotype, although p15 methy-lation doesn't seem to be associated with prognosis.