1,25-dihydroxyvitamin D3 induces biphasic NF-kappaB responses during HL-60 leukemia cells differentiation through protein induction and PI3K/Akt-dependent phosphorylation/degradation of IkappaB

Exp Cell Res. 2007 May 1;313(8):1722-34. doi: 10.1016/j.yexcr.2007.02.022. Epub 2007 Mar 6.

Abstract

1,25-dihydroxyvitamin D(3) (VD(3)) induces differentiation in a number of leukemia cell lines and under various conditions is able to either stimulate or inhibit nuclear factor kappa B (NF-kappaB) activity. Here we report a time-dependent biphasic regulation of NF-kappaB in VD(3)-treated HL-60 leukemia cells. After VD(3) treatment there was an early approximately 4 h suppression and a late 8-72 h prolonged reactivation of NF-kappaB. The reactivation of NF-kappaB was concomitant with increased IKK activities, IKK-mediated IkappaBalpha phosphorylation, p65 phosphorylation at residues S276 and S536, p65 nuclear translocation and p65 recruitment to the NF-kappaB/vitamin D responsive element promoters. In parallel with NF-kappaB stimulation, there was an up-regulation of NF-kappaB controlled inflammatory and anti-apoptotic genes such as TNFalpha, IL-1beta and Bcl-xL. VD(3)-triggered reactivation of NF-kappaB was associated with PI3K/Akt phosphorylation. PI3K/Akt antagonists suppressed VD(3)-stimulated IkappaBalpha phosphorylation as well as NF-kappaB-controlled gene expression. The early approximately 4 h VD(3)-mediated NF-kappaB suppression coincided with a prolonged increase of IkappaBalpha protein which require de novo protein synthesis, lasted for as least 72 h and was insensitive to MAPK, IKK or PI3K/Akt inhibitors. Our data suggest a novel biphasic regulation of NF-kappaB in VD(3)-treated leukemia cells and our results may have provided the first molecular explanation for the contradictory observations reported on VD(3)-mediated immune-regulation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • CD11b Antigen / metabolism
  • Calcitriol / pharmacology*
  • Cell Differentiation*
  • HL-60 Cells
  • Humans
  • I-kappa B Proteins / antagonists & inhibitors
  • I-kappa B Proteins / metabolism*
  • Interleukin-1beta / metabolism
  • MAP Kinase Signaling System / drug effects
  • MAP Kinase Signaling System / physiology
  • NF-kappa B / antagonists & inhibitors
  • NF-kappa B / biosynthesis
  • NF-kappa B / metabolism*
  • Phosphatidylinositol 3-Kinases / physiology*
  • Phosphoinositide-3 Kinase Inhibitors
  • Phosphorylation
  • Protein Kinase Inhibitors / pharmacology
  • Proto-Oncogene Proteins c-akt / antagonists & inhibitors
  • Proto-Oncogene Proteins c-akt / physiology*
  • Signal Transduction
  • Transcription Factor RelA / antagonists & inhibitors
  • Transcription Factor RelA / metabolism
  • Tumor Necrosis Factor-alpha / metabolism
  • Up-Regulation
  • bcl-X Protein / metabolism

Substances

  • BCL2L1 protein, human
  • CD11b Antigen
  • I-kappa B Proteins
  • Interleukin-1beta
  • NF-kappa B
  • Phosphoinositide-3 Kinase Inhibitors
  • Protein Kinase Inhibitors
  • Transcription Factor RelA
  • Tumor Necrosis Factor-alpha
  • bcl-X Protein
  • Proto-Oncogene Proteins c-akt
  • Calcitriol