title: Epigenetic regulation of transcription factor promoter regions by low-dose genistein through mitogen-activated protein kinase and mitogen-and-stress activated kinase 1 nongenomic signaling.
abstract: The phytoestrogen, genistein at low doses nongenomically activates mitogen-activated protein kinase p44/42 (MAPKp44/42) via estrogen receptor alpha (ERα) leading to proliferation of human uterine leiomyoma cells. In this study, we evaluated if MAPKp44/42 could activate downstream effectors such as mitogen- and stress-activated protein kinase 1 (MSK1), which could then epigenetically modify histone H3 by phosphorylation following a low dose (1 μg/ml) of genistein.
  
  
  
  Using hormone-responsive immortalized human uterine leiomyoma (ht-UtLM) cells, we found that genistein activated MAPKp44/42 and MSK1, and also increased phosphorylation of histone H3 at serine10 (H3S10ph) in ht-UtLM cells. Colocalization of phosphorylated MSK1 and H3S10ph was evident by confocal microscopy in ht-UtLM cells (r = 0.8533). Phosphorylation of both MSK1and H3S10ph was abrogated by PD98059 (PD), a MEK1 kinase inhibitor, thereby supporting genistein's activation of MSK1 and Histone H3 was downstream of MAPKp44/42. In proliferative (estrogenic) phase human uterine fibroid tissues, phosphorylated MSK1 and H3S10ph showed increased immunoexpression compared to normal myometrial tissues, similar to results observed in in vitro studies following low-dose genistein administration. Real-time RT-PCR arrays showed induction of growth-related transcription factor genes, EGR1, Elk1, ID1, and MYB (cMyb) with confirmation by western blot, downstream of MAPK in response to low-dose genistein in ht-UtLM cells. Additionally, genistein induced associations of promoter regions of the above transcription factors with H3S10ph as evidenced by Chromatin Immunoprecipitation (ChIP) assays, which were inhibited by PD. Therefore, genistein epigenetically modified histone H3 by phosphorylation of serine 10, which was regulated by MSK1 and MAPK activation.
  
  
  
  Histone H3 phosphorylation possibly represents a mechanism whereby increased transcriptional activation occurs following low-dose genistein exposure.
authors: Molecular Pathogenesis Group, National Toxicology Program (NTP) Laboratory, Division of the NTP (DNTP), National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), U.S. Department of Health and Human Services (HHS), Research Triangle Park, North Carolina, 27709, USA.
authors: Linda
authors: L
authors: Yu
authors: Molecular Pathogenesis Group, National Toxicology Program (NTP) Laboratory, Division of the NTP (DNTP), National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), U.S. Department of Health and Human Services (HHS), Research Triangle Park, North Carolina, 27709, USA.
authors: Kyle
authors: K
authors: Ham
authors: Molecular Pathogenesis Group, National Toxicology Program (NTP) Laboratory, Division of the NTP (DNTP), National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), U.S. Department of Health and Human Services (HHS), Research Triangle Park, North Carolina, 27709, USA.
authors: Xiaohua
authors: X
authors: Gao
authors: Molecular Pathogenesis Group, National Toxicology Program (NTP) Laboratory, Division of the NTP (DNTP), National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), U.S. Department of Health and Human Services (HHS), Research Triangle Park, North Carolina, 27709, USA.
authors: Lysandra
authors: L
authors: Castro
authors: Molecular Pathogenesis Group, National Toxicology Program (NTP) Laboratory, Division of the NTP (DNTP), National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), U.S. Department of Health and Human Services (HHS), Research Triangle Park, North Carolina, 27709, USA.
authors: Yitang
authors: Y
authors: Yan
authors: Biostatistics and Computational Biology Branch, Division of Intramural Research (DIR), NIEHS, NIH, HHS, Research Triangle Park, North Carolina, 27709, USA.
authors: Grace E
authors: GE
authors: Kissling
authors: Signal Transduction Laboratory, DIR, NIEHS, NIH, HHS, Research Triangle Park, North Carolina, 27709, USA.
authors: Charles J
authors: CJ
authors: Tucker
authors: Cellular and Molecular Pathology Branch, DNTP, NIEHS, NIH, HHS, Research Triangle Park, North Carolina, 27709, USA.
authors: Norris
authors: N
authors: Flagler
authors: Molecular Pathogenesis Group, National Toxicology Program (NTP) Laboratory, Division of the NTP (DNTP), National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), U.S. Department of Health and Human Services (HHS), Research Triangle Park, North Carolina, 27709, USA.
authors: Ray
authors: R
authors: Dong
authors: Chromatin and Gene Expression Group, Epigenetics and Stem Cell Biology Laboratory, DIR, NIEHS, NIH, HHS, Research Triangle Park, North Carolina, 27709, USA.
authors: Trevor K
authors: TK
authors: Archer
authors: Molecular Pathogenesis Group, National Toxicology Program (NTP) Laboratory, Division of the NTP (DNTP), National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), U.S. Department of Health and Human Services (HHS), Research Triangle Park, North Carolina, 27709, USA. dixon@niehs.nih.gov.
authors: Darlene
authors: 0000-0002-7001-2985
authors: D
authors: Dixon
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D045744:Cell Line, Tumor; D044127:Epigenesis, Genetic; D019833:Genistein / Q000494:pharmacology*; D006657:Histones / Q000378:metabolism; D006801:Humans; D020935:MAP Kinase Signaling System / Q000187:drug effects*; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D010766:Phosphorylation; D011401:Promoter Regions, Genetic; D011499:Protein Processing, Post-Translational; D038744:Ribosomal Protein S6 Kinases, 90-kDa / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation / Q000187:drug effects
chemical_list: D000970:Antineoplastic Agents; D006657:Histones; D014157:Transcription Factors; D019833:Genistein; D038744:Ribosomal Protein S6 Kinases, 90-kDa; C116919:mitogen and stress-activated protein kinase 1; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3
keywords: Epigenetic; Histone H3; Leiomyoma; MAPKp44/42; MSK1