Insulin-like growth factor I (IGF-I) and IGF binding protein-1 modulate prostate cancer cell growth and apoptosis: possible mediators for the effects of diet and exercise on cancer cell survival

Endocrinology. 2003 Jun;144(6):2319-24. doi: 10.1210/en.2003-221028.


Previous studies showed that serum from men consuming a low fat diet and undergoing exercise intervention (DE) reduced LNCaP cell growth and induced apoptosis in vitro. DE also decreased serum IGF-I and increased serum IGF binding protein-1 (IGFBP-1). The present study evaluates the effects of IGF-I and IGFBP-1 on growth and apoptosis of prostate cancer cells in vitro. When IGF-I was added to the post-DE serum, the reduction in LNCaP cell growth and the induction of apoptosis in medium containing post-DE serum alone were reversed. When IGFBP-1 was added to the pre-DE serum samples, LNCaP cell growth was reduced, and apoptosis was induced. IGF-I, long-R(3)-IGF-I (only binds IGF-I receptor), AL(31)Leu(60)-IGF-I (only binds IGFBPs), antihuman IGF-I receptor antibodies, and IGFBP-1 were then added to LNCaP cultures to determine the independent effects of IGF-I and IGFBP-1 on cell growth. Collectively, the results using these agents show that IGF-I and IGFBP-1 exert opposing effects on LNCaP cell growth and apoptosis, and IGFBP-1 acts mainly through an IGF-dependent mechanism. DE results in a decrease in serum IGF-I with increased IGFBP-1 in vivo that is associated with apoptosis and reduced LNCaP and LAPC-4 prostate cancer cell growth in vitro.

Publication types

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

MeSH terms

  • Apoptosis / drug effects
  • Blood Proteins / pharmacology
  • Cell Division / drug effects
  • Cell Survival / drug effects
  • Diet, Fat-Restricted
  • Dietary Fats / pharmacology
  • Exercise*
  • Humans
  • Insulin-Like Growth Factor Binding Protein 1 / blood
  • Insulin-Like Growth Factor Binding Protein 1 / pharmacology*
  • Insulin-Like Growth Factor I / metabolism
  • Insulin-Like Growth Factor I / pharmacology*
  • Male
  • Prostatic Neoplasms*
  • Tumor Cells, Cultured / cytology
  • Tumor Cells, Cultured / drug effects


  • Blood Proteins
  • Dietary Fats
  • Insulin-Like Growth Factor Binding Protein 1
  • Insulin-Like Growth Factor I