title: HDAC inhibitors sodium butyrate and sodium valproate do not affect human ncor1 and ncor2 gene expression in HL-60 cells.
abstract: AIM. This study was designed to examine whether the class I and class IIa histone deacetylase (HDAC) inhibitors, sodium butyrate and sodium valproate alter the expression of human NCOR1 and/or NCOR2 genes coding for N-CoR (nuclear receptor corepressor) and SMRT (silencing mediator for retinoid and thyroid hormone receptors), respectively.
  
  
  METHODS
  Human leukemia HL-60 cells were treated for 24 h with 0.5 and 1 mM sodium butyrate, 1 to 3 mM sodium valproate, 1 mcM all-trans retinoic acid (ATRA) or cotreated with 1 mcM ATRA and 0.5 mM sodium butyrate. The acetylation of histones H3 and H4 was analysed by western blotting. The levels of NCOR1 and NCOR2 mRNA were determined by quantitative real-time PCR. Expression of NCF2 gene coding for the NADPH oxidase subunit p67phox was evaluated as a marker of myeloid differentiation. Results. Both butyrate and valproate increased the acetylation of histone H3 at Lys9 and/or Lys14 as well as histone H4 at Lys12. Both HDAC inhibitors caused a significant increase in NCF2 mRNA levels without affecting NCOR1 or NCOR2 mRNA levels. Similarly, ATRA alone or in combination with butyrate induced NCF2 gene expression without any significant influence on the expression of NCOR1 or NCOR2 genes.
  
  
  CONCLUSIONS
  We conclude that inhibitors of class I and class IIa HDACs do not alter the expression of human NCOR1 or NCOR2 genes and that the onset of myeloid differentiation is not accompanied by induction or repression of these genes in HL-60 cells.
authors.affiliation: Department of Medical Chemistry and Biochemistry, Palacky University Olomouc, Czech Republic. vrbambv@seznam.cz
authors.forename: Jiri
authors.initials: J
authors.lastname: Vrba
authors.forename: Katerina
authors.initials: K
authors.lastname: Trtkova
authors.forename: Jitka
authors.initials: J
authors.lastname: Ulrichova
mesh_terms: D002087:Butyrates / Q000494:pharmacology*; D002478:Cells, Cultured; D015870:Gene Expression / Q000187:drug effects*; D018922:HL-60 Cells; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology*; D006801:Humans; D019255:NADPH Oxidases / Q000235:genetics; D056971:Nuclear Receptor Co-Repressor 1 / Q000235:genetics*; D056985:Nuclear Receptor Co-Repressor 2 / Q000235:genetics*; D016133:Polymerase Chain Reaction; D014635:Valproic Acid / Q000494:pharmacology*
chemical_list: D002087:Butyrates; D056572:Histone Deacetylase Inhibitors; C539130:NCOR2 protein, human; D056971:Nuclear Receptor Co-Repressor 1; D056985:Nuclear Receptor Co-Repressor 2; D014635:Valproic Acid; D019255:NADPH Oxidases; C527764:NCF2 protein, human