title: Dynamic DNA methylation change in the CpG island region of p15 during human myeloid development.
abstract: We examined the kenetics of p15 methylation and expression during myeloid development. We treated human cord blood CD34+ cells with either GM-CSF alone or in combination with stem cell factor and followed methylation at this locus using bisulfite genomic sequencing. CD34+ cells were found to be either fully methylated or completely unmethylated at 27 CpG dinucleotide sites in exon 1 and at 18 CpG sites in the promoter region of the p15 gene. A time-course study showed that the percentage of the allelic methylation of p15 CpG island increased to approximately 50% to 60% until 7 days after cytokine stimulation, then decreased to less than 10% after 21 days. The methylation was also observed in bone marrow CD34+ cells exposed to GM-CSF. p15 expression varied inversely with methylation. Expression was negligible or at low levels until 14 days, after which it increased substantially. The frequency of myeloid colony-forming cells in the progeny decreased and myeloid-specific markers increased in the later stages. Based on our observations on cells grown with GM-CSF and 5-aza-2'-deoxycytidine, DNA methylation of the p15 promoter region CpG island appears to be associated with proliferation rather than differentiation of normal human myeloid progenitors.
authors.affiliation: Department of Pediatrics, Institute of Organ Transplants, Reconstructive Medicine and Tissue Engineering, Shinshu University School of Medicine, 3-1-1, Asahi, Matsumoto, 390-8621, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Sakashita
authors.forename: K
authors.initials: K
authors.lastname: Koike
authors.forename: T
authors.initials: T
authors.lastname: Kinoshita
authors.forename: M
authors.initials: M
authors.lastname: Shiohara
authors.forename: T
authors.initials: T
authors.lastname: Kamijo
authors.forename: S
authors.initials: S
authors.lastname: Taniguchi
authors.forename: T
authors.initials: T
authors.lastname: Kubota
mesh_terms: D000483:Alleles; D018952:Antigens, CD34 / Q000378:metabolism; D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000235:genetics*; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D018899:CpG Islands; D050762:Cyclin-Dependent Kinase Inhibitor p15; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics*; D004247:DNA / Q000235:genetics; D019175:DNA Methylation; D005312:Fetal Blood / Q000166:cytology / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D015870:Gene Expression; D016147:Genes, Tumor Suppressor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006098:Granulocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D006410:Hematopoiesis / Q000235:genetics* / Q000502:physiology*; D006412:Hematopoietic Stem Cells / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008264:Macrophages / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D019089:Stem Cell Factor / Q000494:pharmacology; D025521:Tumor Suppressor Proteins
chemical_list: D018952:Antigens, CD34; C493966:CDKN2B protein, human; D018797:Cell Cycle Proteins; D050762:Cyclin-Dependent Kinase Inhibitor p15; D019941:Cyclin-Dependent Kinase Inhibitor p16; D019089:Stem Cell Factor; D025521:Tumor Suppressor Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D004247:DNA