Increased expression of insulin receptor substrate-1 in human pancreatic cancer

Biochem Biophys Res Commun. 1996 Mar 27;220(3):886-90. doi: 10.1006/bbrc.1996.0500.


Insulin receptor substrate-1 (IRS-1) is a multisite docking protein implicated in mitogenic signaling following activation of the insulin and insulin-like growth factor I receptors. In the present study we characterized IRS-1 expression in human pancreatic cancer. Northern blot analysis revealed high levels of IRS-1 mRNA transcripts in ASPC-1 and MIA PaCa-2 human pancreatic cancer cell lines, and lower levels in COLO-357, PANC-1, and T3M4 cells. Immunoblotting with anti-IRS-1 antibodies indicated that IRS-1 protein levels paralleled IRS-1 mRNA levels. Analysis of RNA isolated from normal and cancerous human pancreatic tissues indicated that 7 of 16 pancreatic cancer samples overexpressed IRS-1 mRNA transcripts by comparison with the normal pancreas and that insulin mRNA levels were abundant in many tumors. These data suggest that IRS-1 contributes to the signaling pathways that lead to excessive growth stimulation in human pancreatic cancer.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Blotting, Northern
  • Cell Line
  • Colonic Neoplasms
  • Gene Expression* / drug effects
  • Humans
  • Insulin / biosynthesis
  • Insulin / pharmacology
  • Insulin Receptor Substrate Proteins
  • Pancreas / metabolism*
  • Pancreatic Neoplasms / metabolism*
  • Phosphoproteins / biosynthesis*
  • Phosphoproteins / isolation & purification
  • RNA, Messenger / analysis
  • RNA, Messenger / biosynthesis
  • Transcription, Genetic*
  • Tumor Cells, Cultured


  • IRS1 protein, human
  • Insulin
  • Insulin Receptor Substrate Proteins
  • Phosphoproteins
  • RNA, Messenger