title: EVI1 Interferes with Myeloid Maturation via Transcriptional Repression of Cebpa, via Binding to Two Far Downstream Regulatory Elements.
abstract: One mechanism by which oncoproteins work is through perturbation of cellular maturation; understanding the mechanisms by which this occurs can lead to the development of targeted therapies. EVI1 is a zinc finger oncoprotein involved in the development of acute myeloid leukemia; previous work has shown it to interfere with the maturation of granulocytes from immature precursors. Here we investigate the mechanism by which that occurs, using an immortalized hematopoietic progenitor cell line, EML-C1, as a model system. We document that overexpression of EVI1 abrogates retinoic acid-induced maturation of EML cells into committed myeloid cells, a process that can be documented by the down-regulation of stem cell antigen-1 and acquisition of responsiveness to granulocyte-macrophage colony-stimulating factor. We show that this requires DNA binding capacity of EVI1, suggesting that downstream target genes are involved. We identify the myeloid regulator Cebpa as a target gene and identify two EVI1 binding regions within evolutionarily conserved enhancer elements at +35 and +37 kb relative to the gene. EVI1 can strongly suppress Cebpa transcription, and add-back of Cebpa into EVI1-expressing EML cells partially corrects the block in maturation. We identify the DNA sequences to which EVI1 binds at +35 and +37 kb and show that mutation of one of these releases Cebpa from EVI1-induced suppression. We observe a more complex picture in primary bone marrow cells, where EVI1 suppresses Cebpa in stem cells but not in more committed progenitors. Our data thus identify a regulatory node by which EVI1 contributes to leukemia, and this represents a possible therapeutic target for treatment of EVI1-expressing leukemia.
authors.affiliation: From the Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, New York 14642 and.
authors.forename: Michael
authors.initials: M
authors.lastname: Wilson
authors.affiliation: the Department of Pathology, Yale University, New Haven, Connecticut 06520.
authors.forename: Vasiliki
authors.initials: V
authors.lastname: Tsakraklides
authors.affiliation: the Department of Pathology, Yale University, New Haven, Connecticut 06520.
authors.forename: Minh
authors.initials: M
authors.lastname: Tran
authors.affiliation: the Department of Pathology, Yale University, New Haven, Connecticut 06520.
authors.forename: Ying-Yi
authors.initials: YY
authors.lastname: Xiao
authors.affiliation: From the Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, New York 14642 and yi_zhang@urmc.rochester.edu.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: From the Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, New York 14642 and archibald_perkins@urmc.rochester.edu.
authors.forename: Archibald S
authors.initials: AS
authors.lastname: Perkins
mesh_terms: D000818:Animals; D000950:Antigens, Ly / Q000235:genetics / Q000378:metabolism; D001854:Bone Marrow Cells / Q000378:metabolism; D022762:CCAAT-Enhancer-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation; D002460:Cell Line; D006224:Cricetinae; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D007938:Leukemia / Q000235:genetics / Q000378:metabolism; D000074008:MDS1 and EVI1 Complex Locus Protein; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D011519:Proto-Oncogenes / Q000235:genetics; D020218:Response Elements; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D000950:Antigens, Ly; D022762:CCAAT-Enhancer-Binding Proteins; C530718:CEBPA protein, mouse; D004268:DNA-Binding Proteins; C074650:Ly6a protein, mouse; D000074008:MDS1 and EVI1 Complex Locus Protein; C499305:Mecom protein, mouse; D008565:Membrane Proteins; D014157:Transcription Factors
keywords: CCAAT-enhancer-binding protein (C/EBP); leukemia; myeloid cell; transcription regulation; transcription target gene