Polyamines as modifiers of genetic risk factors in human intestinal cancers

Biochem Soc Trans. 2003 Apr;31(2):388-92. doi: 10.1042/bst0310388.


Polyamines are downstream mediators of genetic risk factors in human intestinal cancers. The adenomatous polyposis coli (APC) tumour-suppressor gene, which is mutated in essentially all human colon cancers, regulates the expression of several e-box transcription factors. These factors, in turn, regulate the transcription of ornithine decarboxylase (ODC), the first enzyme in polyamine synthesis. The Kirsten ras ( K-ras ) oncogene regulates the expression of several genes, including suppressing the expression of peroxisomal proliferator-activated receptor gamma (PPARgamma). This PPAR, in turn, activates the expression of the spermidine/spermine-N(1)-acetyltransferase (SSAT), the first enzyme in polyamine catabolism. The non-steroidal anti-inflammatory drug (NSAID) sulindac induces the transcription of SSAT via activation of PPARgamma. Inactivation of the APC tumour-suppressor gene, and the activation of K-ras, have a combined effect on increasing tissue polyamine contents due to increased synthesis and decreased catabolism of the polyamines. Pharmacological strategies for suppressing ODC (e.g. the enzyme-activated inhibitor alpha-difluoromethylornithine) and activating SSAT (e.g. NSAIDs) are potent inhibitors of intestinal carcinogenesis in rodent models. Clinical trials combining these classes of agent in humans with risk factors for colon cancer are in progress.

Publication types

  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Antineoplastic Agents / pharmacology
  • Biogenic Polyamines / biosynthesis
  • Biogenic Polyamines / metabolism
  • Biogenic Polyamines / physiology*
  • Enzyme Inhibitors / pharmacology
  • Gene Expression Regulation, Enzymologic
  • Humans
  • Intestinal Neoplasms / genetics
  • Intestinal Neoplasms / prevention & control*
  • Risk Factors


  • Antineoplastic Agents
  • Biogenic Polyamines
  • Enzyme Inhibitors