RUNX1 regulates corepressor interactions of PU.1.

The transcription factor (TF) RUNX1 cooperates with lineage-specifying TFs (eg, PU.1/SPI1) to activate myeloid differentiation genes, such as macrophage and granulocyte macrophage colony-stimulating factor receptors (MCSFR and GMCSFR). Disruption of cooperative gene activation could contribute to aberrant repression of differentiation genes and leukemogenesis initiated by mutations and translocations of RUNX1. To investigate the mechanisms underlying cooperative gene activation, the effects of Runx1 deficiency were examined in an in vitro model of Pu.1-driven macrophage differentiation and in primary cells. Runx1 deficiency decreased Pu.1-mediated activation of Mcsfr and Gmcsfr, accompanied by decreased histone acetylation at the Mcsfr and Gmcsfr promoters, and increased endogenous corepressor (Eto2, Sin3A, and Hdac2) coimmunoprecipitation with Pu.1. In cotransfection experiments, corepressors were excluded from a multiprotein complex containing full-length RUNX1 and PU.1. However, corepressors interacted with PU.1 if wild-type RUNX1 was replaced with truncated variants associated with leukemia. Histone deacetylase (HDAC) enzyme activity is a major component of corepressor function. HDAC inhibition using suberoylanilide hydroxamic acid or MS-275 significantly increased MCSFR and GMCSFR expression in leukemia cell lines that express PU.1 and mutated or translocated RUNX1. RUNX1 deficiency is associated with persistent corepressor interaction with PU.1. Thus, inhibiting HDAC can partly compensate for the functional consequences of RUNX1 deficiency.

[1]  Y. Okuno,et al.  PU.1 is a major downstream target of AML1 (RUNX1) in adult mouse hematopoiesis , 2008, Nature Genetics.

[2]  J. Downing,et al.  AML1, the Target of Multiple Chromosomal Translocations in Human Leukemia, Is Essential for Normal Fetal Liver Hematopoiesis , 1996, Cell.

[3]  J. P. Meza-Espinoza,et al.  Increased expression of AML1‐a and acquired chromosomal abnormalities in childhood acute lymphoblastic leukemia , 2004, Hematological oncology.

[4]  C. Preudhomme,et al.  Are PU.1 mutations frequent genetic events in acute myeloid leukemia (AML)? , 2002, Blood.

[5]  John Anastasi,et al.  Cooperative and antagonistic interplay between PU.1 and GATA-2 in the specification of myeloid cell fates. , 2002, Immunity.

[6]  T. Tamura,et al.  In vivo complex formation of PU.1 with HDAC1 associated with PU.1-mediated transcriptional repression , 2001, Oncogene.

[7]  M. Ohki,et al.  t(8;21) breakpoints on chromosome 21 in acute myeloid leukemia are clustered within a limited region of a single gene, AML1. , 1991, Proceedings of the National Academy of Sciences of the United States of America.

[8]  S. Boehrer,et al.  Valproic acid stimulates proliferation and self-renewal of hematopoietic stem cells. , 2005, Cancer research.

[9]  Daniel Nowak,et al.  Differentiation therapy of leukemia: 3 decades of development. , 2009, Blood.

[10]  Y. Hashimoto,et al.  Physical and functional interactions between the transcription factor PU.1 and the coactivator CBP , 1999, Oncogene.

[11]  J. Downing,et al.  Haploinsufficiency of AML1 results in a decrease in the number of LTR-HSCs while simultaneously inducing an increase in more mature progenitors. , 2004, Blood.

[12]  M. Merika,et al.  Recruitment of CBP/p300 by the IFN beta enhanceosome is required for synergistic activation of transcription. , 1998, Molecular cell.

[13]  J. Maciejewski,et al.  Decitabine Maintains Hematopoietic Precursor Self-Renewal by Preventing Repression of Stem Cell Genes by a Differentiation-Inducing Stimulus , 2010, Molecular Cancer Therapeutics.

[14]  D. Tenen,et al.  PU.1 (Spi-1) and C/EBP alpha regulate the granulocyte colony-stimulating factor receptor promoter in myeloid cells. , 1996, Blood.

[15]  Clara Nervi,et al.  Histone deacetylase inhibitor valproic acid enhances the cytokine-induced expansion of human hematopoietic stem cells. , 2005, Cancer research.

[16]  D. Eberhard,et al.  Corecruitment of the Grg4 repressor by PU.1 is critical for Pax5‐mediated repression of B‐cell‐specific genes , 2004, EMBO reports.

[17]  J. Downing,et al.  Genomic analysis reveals few genetic alterations in pediatric acute myeloid leukemia , 2009, Proceedings of the National Academy of Sciences.

[18]  M. Carey,et al.  The Enhanceosome and Transcriptional Synergy , 1998, Cell.

[19]  D. Tenen,et al.  Multiple Functional Domains of AML1: PU.1 and C/EBPα Synergize with Different Regions of AML1 , 1998, Molecular and Cellular Biology.

[20]  T. Gu,et al.  Auto-Inhibition of Ets-1 Is Counteracted by DNA Binding Cooperativity with Core-Binding Factor α2 , 2000, Molecular and Cellular Biology.

[21]  D. Tenen,et al.  PU.1 (Spi-1) and C/EBP alpha regulate expression of the granulocyte-macrophage colony-stimulating factor receptor alpha gene , 1995, Molecular and cellular biology.

[22]  T. Sakurai,et al.  Direct association between PU.1 and MeCP2 that recruits mSin3A-HDAC complex for PU.1-mediated transcriptional repression , 2003, Oncogene.

[23]  G. Nucifora,et al.  SUV39H1 interacts with AML1 and abrogates AML1 transactivity. AML1 is methylated in vivo , 2003, Oncogene.

[24]  T. Naoe,et al.  Histone deacetylase inhibitors are the potent inducer/enhancer of differentiation in acute myeloid leukemia: a new approach to anti-leukemia therapy , 1999, Leukemia.

[25]  Laetitia Bataillé,et al.  Cooperation between the GATA and RUNX factors Serpent and Lozenge during Drosophila hematopoiesis , 2003, The EMBO journal.

[26]  J. Kutok,et al.  Acute myeloid leukemia induced by graded reduction of a lineage-specific transcription factor, PU.1 , 2004, Nature Genetics.

[27]  E. Andreu,et al.  RUNX/AML and C/EBP factors regulate CD11a integrin expression in myeloid cells through overlapping regulatory elements. , 2003, Blood.

[28]  H. Steen,et al.  Differentiation-Dependent Interactions between RUNX-1 and FLI-1 during Megakaryocyte Development , 2008, Molecular and Cellular Biology.

[29]  P. Pandolfi,et al.  Therapeutic targeting of transcription in acute promyelocytic leukemia by use of an inhibitor of histone deacetylase. , 1998, Journal of the National Cancer Institute.

[30]  E. Scott,et al.  Requirement of transcription factor PU.1 in the development of multiple hematopoietic lineages. , 1994, Science.

[31]  H. Hirai,et al.  An acute myeloid leukemia gene, AML1, regulates hemopoietic myeloid cell differentiation and transcriptional activation antagonistically by two alternative spliced forms. , 1995, The EMBO journal.

[32]  T. Haferlach,et al.  Characterization of a new myeloid leukemia cell line with normal cytogenetics (CG-SH). , 2009, Leukemia research.

[33]  T. Graf,et al.  Mutual activation of Ets‐1 and AML1 DNA binding by direct interaction of their autoinhibitory domains , 1999, The EMBO journal.

[34]  C. Pirola,et al.  Low Mpl receptor expression in a pedigree with familial platelet disorder with predisposition to acute myelogenous leukemia and a novel AML1 mutation. , 2005, Blood.

[35]  Ming Yan,et al.  A previously unidentified alternatively spliced isoform of t(8;21) transcript promotes leukemogenesis , 2006, Nature Medicine.

[36]  Y. Saunthararajah,et al.  Inhibitors of histone deacetylase relieve ETO-mediated repression and induce differentiation of AML1-ETO leukemia cells. , 1999, Cancer research.

[37]  Carl W. Miller,et al.  C/EBP-β, C/EBP-δ, PU.1, AML1 genes: mutational analysis in 381 samples of hematopoietic and solid malignancies , 2002 .

[38]  Amit Verma,et al.  AML1-ETO Decreases ETO-2 (MTG16) Interactions with Nuclear Receptor Corepressor, an Effect That Impairs Granulocyte Differentiation , 2004, Cancer Research.

[39]  J. Sierra,et al.  ETO sequence may be dispensable in some AML1-ETO leukemias. , 2002, Blood.

[40]  Carl W. Miller,et al.  C/EBP-beta, C/EBP-delta, PU.1, AML1 genes: mutational analysis in 381 samples of hematopoietic and solid malignancies. , 2002, Leukemia research.

[41]  G. Fejer,et al.  Oct-1 Maintains an Intermediate, Stable State of HLA-DRA Promoter Repression in Rb-defective Cells , 2004, Journal of Biological Chemistry.

[42]  Nicola K. Wilson,et al.  The mechanism of repression of the myeloid‐specific c‐fms gene by Pax5 during B lineage restriction , 2006, The EMBO journal.

[43]  Y. Kanno,et al.  Intrinsic Transcriptional Activation-Inhibition Domains of the Polyomavirus Enhancer Binding Protein 2/Core Binding Factor α Subunit Revealed in the Presence of the β Subunit , 1998, Molecular and Cellular Biology.

[44]  J. Coffman.  Runx transcription factors and the developmental balance between cell proliferation and differentiation , 2003, Cell biology international.

[45]  N. Mahmud,et al.  Modification of hematopoietic stem cell fate by 5aza 2'deoxycytidine and trichostatin A. , 2004, Blood.

[46]  T. Kyo,et al.  Hyperactivation of the RAS signaling pathway in myelodysplastic syndrome with AML1/RUNX1 point mutations , 2006, Leukemia.

[47]  D. Tenen,et al.  CCAAT Enhancer-Binding Protein ( C / EBP ) and AML 1 ( CBF a 2 ) Synergistically Activate the Macrophage Colony-Stimulating Factor Receptor Promoter , 1995 .

[48]  K. Senger,et al.  Gene repression by coactivator repulsion. , 2000, Molecular cell.

[49]  Kamaleldin E Elagib,et al.  RUNX1 and GATA-1 coexpression and cooperation in megakaryocytic differentiation. , 2003, Blood.

[50]  M. Minden,et al.  Heterozygous PU.1 mutations are associated with acute myeloid leukemia. , 2002, Blood.