Transactivation of Src, PDGF receptor, and Akt is involved in IL-1beta-induced ICAM-1 expression in A549 cells

J Cell Physiol. 2007 Jun;211(3):771-80. doi: 10.1002/jcp.20987.

Abstract

In previous study, interleukin-1beta (IL-1beta) has been shown to induce ICAM-1 expression through MAPKs and NF-kappaB in A549 cells. In addition to these pathways, transactivation of non-receptor tyrosine kinase (Src), PDGF receptors (PDGFRs), and phosphatidylinositol 3-kinase (PI3K)/Akt has been implicated in the expression of inflammatory genes. Here, we further investigated whether these different mechanisms participating in IL-1beta-induced ICAM-1 expression in A549 cells. We initially observed that IL-1beta-induced ICAM-1 promoter activity was attenuated by the inhibitors of Src (PP1), PDGFR (AG1296), PI3-K (LY294002 and wortmannin), and Akt (SH-5), revealed by reporter gene assay, Western blotting, and RT-PCR analyses. The involvement of Src and PI3-K/Akt in IL-1beta-induced ICAM-1 expression was significantly attenuated by transfection of A549 cells with dominant negative plasmids of Src, p85 and Akt, respectively. Src, PDGFR, and PI3K/Akt mediated the effects of IL-1beta because pretreatment with PP1, AG1296, and wortmannin also abrogated IL-1beta-stimulated Src, PDGFR, and Akt phosphorylation, respectively. Moreover, pretreatment with p300 inhibitor (curcumin) also blocked ICAM-1 expression. We further confirmed that p300 was associated with ICAM-1 promoter which was dynamically linked to histone H4 acetylation stimulated by IL-1beta, determined by chromatin immunoprecipitation assay. Association of p300 and histone-H4 to ICAM-1 promoter was inhibited by LY294002. Up-regulation of ICAM-1 enhanced the adhesion of neutrophils onto A549 cell monolayer exposed to IL-1beta, which was inhibited by PP1, AG1296, LY294002, wortmannin, and helenalin. These results suggested that Akt phosphorylation mediated through transactivation of Src/PDGFR promotes the transcriptional p300 activity and eventually leads to ICAM-1 expression induced by IL-1beta.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylation
  • Cell Adhesion / drug effects
  • Cell Adhesion / immunology
  • Cell Line, Tumor
  • Gene Expression / drug effects
  • Gene Expression / physiology
  • Histones / metabolism
  • Humans
  • Intercellular Adhesion Molecule-1 / genetics*
  • Interleukin-1beta / pharmacology*
  • Lung Neoplasms
  • Mitogen-Activated Protein Kinases / metabolism
  • NF-kappa B / metabolism
  • Neutrophils / cytology
  • Neutrophils / drug effects
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphorylation
  • Promoter Regions, Genetic / physiology
  • Proto-Oncogene Proteins c-akt / metabolism*
  • RNA, Messenger / metabolism
  • Receptors, Platelet-Derived Growth Factor / metabolism*
  • Respiratory Mucosa / cytology
  • Transcription, Genetic / drug effects
  • Transcription, Genetic / physiology
  • p300-CBP Transcription Factors / metabolism
  • src-Family Kinases / metabolism*

Substances

  • Histones
  • Interleukin-1beta
  • NF-kappa B
  • RNA, Messenger
  • Intercellular Adhesion Molecule-1
  • p300-CBP Transcription Factors
  • Phosphatidylinositol 3-Kinases
  • Receptors, Platelet-Derived Growth Factor
  • src-Family Kinases
  • Proto-Oncogene Proteins c-akt
  • Mitogen-Activated Protein Kinases