title: p15 mRNA expression detected by real-time quantitative reverse transcriptase-polymerase chain reaction correlates with the methylation density of the gene in adult acute leukemia.
abstract: Cyclin-dependent kinase inhibitor p15 is frequently inactivated by either methylation or deletion in patients with acute leukemia. To examine pathologic and clinical significance of the p15 gene inactivation, we established a quantitative assay of p15 mRNA expression in the bone marrow cells by real-time quantitative reverse transcriptase-polymerase chain reaction. p15 mRNA expression in 14 patients with precursor B-cell acute lymphoblastic leukemia (PBC-ALL) well correlated with status of deletion and methylation in the p15 gene analyzed by Southern blotting. Furthermore, two patients with PBC-ALL and 11 acute myeloblastic leukemia (AML) were quantitatively examined for p15 gene methylation using bisulfite genomic sequencing. The data showed that p15 mRNA expression significantly correlated with the CpG island methylation density. Among 108 AML patients, p15 mRNA expression was significantly lower in the myeloid lineage (M1, M2, M3) than the monocytic lineage (M4, M5) (P = 0.0019). Above all, the majority of M3 patients showed low p15 expression compared with M1 and M2 patients (P = 0.029). These observations suggest that quantitative analysis of p15 mRNA will be useful to evaluate transcriptional repression of the p15 gene caused by various degrees of methylation.
authors.affiliation: Department of Internal Medicine II, Kumamoto University School of Medicine, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
authors.forename: Naofumi
authors.initials: N
authors.lastname: Matsuno
authors.forename: Koyu
authors.initials: K
authors.lastname: Hoshino
authors.forename: Tomoko
authors.initials: T
authors.lastname: Nanri
authors.forename: Toshiro
authors.initials: T
authors.lastname: Kawakita
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Suzushima
authors.forename: Fumio
authors.initials: F
authors.lastname: Kawano
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Mitsuya
authors.forename: Norio
authors.initials: N
authors.lastname: Asou
mesh_terms: D000208:Acute Disease; D000328:Adult; D001854:Bone Marrow Cells / Q000378:metabolism / Q000473:pathology; D002051:Burkitt Lymphoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D018797:Cell Cycle Proteins / Q000235:genetics*; D019070:Cell Lineage; D018899:CpG Islands; D050762:Cyclin-Dependent Kinase Inhibitor p15; D019175:DNA Methylation; D015973:Gene Expression Regulation, Leukemic; D006801:Humans; D007951:Leukemia, Myeloid / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017384:Sequence Deletion; D014407:Tumor Cells, Cultured; D025521:Tumor Suppressor Proteins / Q000235:genetics*
chemical_list: C493966:CDKN2B protein, human; D018797:Cell Cycle Proteins; D050762:Cyclin-Dependent Kinase Inhibitor p15; D012333:RNA, Messenger; D025521:Tumor Suppressor Proteins