1alpha,25-dihydroxyvitamin D3 and a variety of its natural metabolites transcriptionally repress nuclear-factor-kappaB-mediated interleukin-8 gene expression

Eur J Biochem. 1997 Nov 15;250(1):63-71. doi: 10.1111/j.1432-1033.1997.00063.x.


Regulation of interleukin-8 (IL-8) gene transcription occurs mainly through the sequences -94 to -71 of the 5'-flanking region of the IL-8 gene, involving the transcription factors nuclear factor for interleukin-6 (NF-IL-6) and nuclear factor kappaB (NF-kappaB). The human melanoma cell line A3 was derived from G-361 cells by stable transfection with an IL-8 promoter-luciferase construct containing these sequences. 1alpha,25-Dihydroxyvitamin D3 (calcitriol) repressed IL-8 promoter activity induced by tumor necrosis factor-alpha (TNF-alpha) by 50%, compared to 30% inhibition using dexamethasone, an effect consistent with its effect on TNF-alpha-induced IL-8 release and IL-8 mRNA levels. A variety of vitamin D metabolites caused the same repressive effect on IL-8 promoter activation as calcitriol. However, only those metabolites which were able to transactivate a classical vitamin D response element had the ability to repress IL-8 promoter activation, suggesting that this repression is mediated via vitamin D receptor (VDR). Furthermore, overexpression of VDR in the parental G-361 cell line enhanced the repressive effect of calcitriol on activation of the IL-8 promoter by either TNF-alpha stimulation or overexpression of the NF-kappaB subunit p65. Electrophoretic mobility shift assays using nuclear extracts from A3 cells showed that calcitriol decreased the abundance of nuclear factors bound to the NF-kappaB binding site of the IL-8 promoter and this reduced binding of NF-kappaB proteins presumably contributes to its inhibitory action.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Binding Sites
  • Blotting, Northern
  • Calcitriol / metabolism
  • Calcitriol / pharmacology*
  • Calcium-Binding Proteins*
  • Dexamethasone / pharmacology
  • Gene Expression Regulation / drug effects*
  • Genes, Reporter
  • Humans
  • Interleukin-8 / genetics*
  • Interleukin-8 / metabolism
  • Membrane Glycoproteins
  • NF-kappa B / genetics
  • NF-kappa B / metabolism*
  • Nerve Tissue Proteins
  • Nuclear Proteins / analysis
  • Nuclear Proteins / metabolism
  • Promoter Regions, Genetic / genetics
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Receptors, Calcitriol / metabolism
  • Synaptotagmin I
  • Synaptotagmins
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Transcription, Genetic / drug effects*
  • Transcriptional Activation
  • Transfection
  • Tumor Cells, Cultured
  • Tumor Necrosis Factor-alpha / pharmacology


  • Calcium-Binding Proteins
  • Interleukin-8
  • Membrane Glycoproteins
  • NF-kappa B
  • Nerve Tissue Proteins
  • Nuclear Proteins
  • RNA, Messenger
  • Receptors, Calcitriol
  • Synaptotagmin I
  • Transcription Factors
  • Tumor Necrosis Factor-alpha
  • Synaptotagmins
  • Dexamethasone
  • Calcitriol