Tumor necrosis factor alpha stimulates invasion of Src-activated intestinal cells

Gastroenterology. 2002 Feb;122(2):331-9. doi: 10.1053/gast.2002.31023.


Background & aims: Src activation is correlated with progression of colorectal cancer (CRC). CRCs accompanied by ulcerative colitis, chronic inflammation in the colon, often have elevated Src activity, and ulcerative colitis-related CRCs are more likely to become invasive, whereas Ras activation is rarely associated with this disease. The aim of this study was to investigate the effects of a proinflammatory cytokine, tumor necrosis factor alpha (TNF-alpha), on the invasive properties of epithelial cells constitutively expressing activated Ras or Src.

Methods: A cell line derived from intestinal epithelia was transfected with a v-src- or v-H-ras-expressing vector. The effect of TNF-alpha on morphologic changes in colonies cultured in soft agar was determined. Src protein kinase activity, peroxide production, E-cadherin expression levels, and the phosphorylation status of beta-catenin and E-cadherin were determined. The invasive potential of these cells was determined by measuring cell motility and using an in vitro invasion assay.

Results: TNF-alpha altered the colony morphology of src-, but not ras-expressing cells. TNF-alpha increased peroxide production, leading to Src protein expression as well as Src activity in src transfectants. Activation of Src by TNF-alpha led to reduced E-cadherin levels and enhanced invasion of src transfectants. Pyrrolidine dithiocarbamate and herbimycin A inhibited these effects.

Conclusion: These results indicate that Src kinase activation enhances the response of epithelial cells to TNF-alpha leading to increased invasion through mechanisms that involve production of reactive oxygen intermediates.

MeSH terms

  • Agar
  • Animals
  • Antineoplastic Agents / pharmacology*
  • Antioxidants / pharmacology
  • Cadherins / metabolism
  • Cell Line, Transformed
  • Cell Movement / physiology*
  • Cytoskeletal Proteins / metabolism
  • Hydrogen Peroxide / metabolism
  • Intestinal Mucosa / cytology
  • Neoplasm Invasiveness / physiopathology
  • Oncogene Protein p21(ras) / genetics
  • Oncogene Protein p21(ras) / metabolism
  • Oncogene Protein pp60(v-src) / genetics
  • Oncogene Protein pp60(v-src) / metabolism*
  • Oxidative Stress / drug effects
  • Oxidative Stress / physiology
  • Phosphotyrosine / metabolism
  • Pyrrolidines / pharmacology
  • Rats
  • Thiocarbamates / pharmacology
  • Trans-Activators*
  • Transfection
  • Tumor Necrosis Factor-alpha / pharmacology*
  • Tyrosine / metabolism
  • beta Catenin


  • Antineoplastic Agents
  • Antioxidants
  • Cadherins
  • Ctnnb1 protein, rat
  • Cytoskeletal Proteins
  • Pyrrolidines
  • Thiocarbamates
  • Trans-Activators
  • Tumor Necrosis Factor-alpha
  • beta Catenin
  • Phosphotyrosine
  • pyrrolidine dithiocarbamic acid
  • Tyrosine
  • Agar
  • Hydrogen Peroxide
  • Oncogene Protein pp60(v-src)
  • Oncogene Protein p21(ras)