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Updated: Aug 13, 2026

Identification of Inositol Phosphate or Phosphoinositide Interacting Proteins by Affinity Chromatography Coupled to Western Blot or Mass Spectrometry
08:07

Identification of Inositol Phosphate or Phosphoinositide Interacting Proteins by Affinity Chromatography Coupled to Western Blot or Mass Spectrometry

Published on: July 26, 2019

TGF-beta isoforms fail to modulate inositol phosphates and cAMP in normal and tumour-derived human oral keratinocytes

A J Collier1, K A Elsegood, W A Yeudall

  • 1Department of Oral and Dental Science, University of Bristol, UK.

Biochimica Et Biophysica Acta
|March 1, 1996
PubMed

Insights

Transforming growth factor-beta (TGF-β) does not regulate inositol phosphate or cyclic adenosine monophosphate (cAMP) in oral keratinocytes. This study found no evidence of these pathways mediating TGF-β signal transduction in normal or tumor cells.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Cancer Research

Background:

  • Transforming growth factor-beta (TGF-β) plays a crucial role in regulating cell growth, differentiation, and apoptosis.
  • Previous studies indicated that human oral keratinocytes express TGF-β receptors and exhibit varied responses to TGF-β isoforms.
  • The specific intracellular signaling pathways mediating TGF-β effects in oral keratinocytes remained unclear.

Purpose of the Study:

  • To investigate the role of inositol phosphate and cyclic adenosine monophosphate (cAMP) signaling pathways in mediating the cellular responses to TGF-β 1, TGF-β 2, and TGF-β 3.
  • To determine if these second messenger systems are involved in TGF-β signal transduction in normal and tumor-derived human oral keratinocytes.

Main Methods:

  • Cultured normal and tumor-derived human oral keratinocytes were treated with TGF-β 1, -β 2, and -β 3.
  • Inositol phosphate levels were measured following stimulation with bradykinin or serum, and in response to TGF-β treatment.
  • Cyclic adenosine monophosphate (cAMP) levels were assessed after treatment with TGF-β isoforms, forskolin (an adenylate cyclase agonist), and dibutyryl cAMP (a cAMP analogue).

Main Results:

  • TGF-β 1, -β 2, and -β 3 failed to modulate inositol phosphate levels in oral keratinocytes.
  • Basal inositol phosphate levels correlated with cell differentiation but not with TGF-β responsiveness.
  • TGF-β isoforms did not affect cAMP levels in tumor-derived cells, even when adenylate cyclase was activated; cAMP analogues did not mimic TGF-β effects.

Conclusions:

  • Transforming growth factor-beta (TGF-β) signal transduction in normal and tumor-derived human oral keratinocytes is not mediated through inositol phosphate or cAMP pathways.
  • These findings exclude common second messenger systems from TGF-β signaling in this cellular context.
  • Further research is needed to elucidate the precise molecular mechanisms underlying TGF-β action in oral keratinocytes.

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