title: Entinostat up-regulates the CAMP gene encoding LL-37 via activation of STAT3 and HIF-1α transcription factors.
abstract: Bacterial resistance against classical antibiotics is a growing problem and the development of new antibiotics is limited. Thus, novel alternatives to antibiotics are warranted. Antimicrobial peptides (AMPs) are effector molecules of innate immunity that can be induced by several compounds, including vitamin D and phenyl-butyrate (PBA). Utilizing a luciferase based assay, we recently discovered that the histone deacetylase inhibitor Entinostat is a potent inducer of the CAMP gene encoding the human cathelicidin LL-37. Here we investigate a mechanism for the induction and also find that Entinostat up-regulates human β-defensin 1. Analysis of the CAMP promoter sequence revealed binding sites for the transcription factors STAT3 and HIF-1α. By using short hairpin RNA and selective inhibitors, we found that both transcription factors are involved in Entinostat-induced expression of LL-37. However, only HIF-1α was found to be recruited to the CAMP promoter, suggesting that Entinostat activates STAT3, which promotes transcription of CAMP by increasing the expression of HIF-1α. Finally, we provide in vivo relevance to our findings by showing that Entinostat-elicited LL-37 expression was impaired in macrophages from a patient with a STAT3-mutation. Combined, our findings support a role for STAT3 and HIF-1α in the regulation of LL-37 expression.
authors.affiliation: Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden.
authors.forename: Erica
authors.initials: E
authors.lastname: Miraglia
authors.affiliation: Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden.
authors.forename: Frank
authors.initials: F
authors.lastname: Nylén
authors.affiliation: Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Katarina
authors.initials: K
authors.lastname: Johansson
authors.affiliation: Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Elias
authors.initials: E
authors.lastname: Arnér
authors.affiliation: Institute of Environmental Medicine, Division of Biochemical Toxicology, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Marcus
authors.initials: M
authors.lastname: Cebula
authors.affiliation: Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Susan
authors.initials: S
authors.lastname: Farmand
authors.affiliation: Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden.
authors.forename: Håkan
authors.initials: H
authors.lastname: Ottosson
authors.affiliation: Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden.
authors.forename: Roger
authors.initials: R
authors.lastname: Strömberg
authors.affiliation: Biomedical Center, University of Iceland, Reykjavík, Iceland.
authors.forename: Gudmundur H
authors.initials: GH
authors.lastname: Gudmundsson
authors.affiliation: Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden.
authors.forename: Birgitta
authors.initials: B
authors.lastname: Agerberth
authors.affiliation: Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden.
authors.forename: Peter
authors.initials: P
authors.lastname: Bergman
mesh_terms: D023181:Antimicrobial Cationic Peptides; D001549:Benzamides / Q000494:pharmacology*; D054804:Cathelicidins / Q000819:agonists / Q000235:genetics* / Q000378:metabolism; D017930:Genes, Reporter; D057809:HEK293 Cells; D019073:HT29 Cells; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology*; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D007589:Job Syndrome / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008264:Macrophages / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D061251:Primary Cell Culture; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011725:Pyridines / Q000494:pharmacology*; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D050796:STAT3 Transcription Factor / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction; D015533:Transcriptional Activation
chemical_list: D023181:Antimicrobial Cationic Peptides; D001549:Benzamides; D054804:Cathelicidins; C497442:HIF1A protein, human; D056572:Histone Deacetylase Inhibitors; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D011725:Pyridines; D034741:RNA, Small Interfering; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; C118739:entinostat; D008156:Luciferases