IGF-I receptor signaling in a prostatic cancer cell line with a PTEN mutation

Oncogene. 2000 May 18;19(22):2687-94. doi: 10.1038/sj.onc.1203587.

Abstract

LNCaP prostatic cancer cells are characterized by having a PTEN mutation, low levels of type 1 insulin-like growth factor receptor (IGF-IR) and no IRS-1, one of the major substrates of the IGF-IR. The absence of IRS-1, an activator of PI3-kinase, is compensated in these cells by the mutation in PTEN, an inhibitor of PI3-kinase. However, IGF-IR signaling in the absence of IRS-1 can cause cell differentiation and growth arrest. We hypothesized that these three characteristics may not be unrelated, specifically that, together, they may favor the metastatic spread of prostatic cancer cells without decreasing their growth potential. In support of this hypothesis, we report here that: (1) IRS-1 expression increases cell adhesion and decreases cell motility; (2) over-expression of the IGF-IR, in the absence of IRS-1, causes growth arrest and (3) a combination of IGF-IR and IRS-1 restores the transformed phenotype of LNCaP cells. These findings suggest a mechanism by which prostatic cancer cells can achieve metastatic potential without interfering with their growth potential. Oncogene (2000).

Publication types

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

MeSH terms

  • Animals
  • Cell Adhesion
  • Cell Movement / genetics
  • Gene Expression Regulation, Neoplastic*
  • Genes, Tumor Suppressor
  • Germ-Line Mutation
  • Humans
  • Male
  • Mice
  • Mice, Nude
  • Neoplasm Invasiveness / genetics
  • PTEN Phosphohydrolase
  • Phosphoric Monoester Hydrolases / genetics*
  • Phosphoric Monoester Hydrolases / metabolism*
  • Prostatic Neoplasms / genetics*
  • Prostatic Neoplasms / metabolism*
  • Prostatic Neoplasms / pathology
  • Receptor, IGF Type 1 / metabolism*
  • Signal Transduction / genetics*
  • Tumor Cells, Cultured
  • Tumor Suppressor Proteins*

Substances

  • Tumor Suppressor Proteins
  • Receptor, IGF Type 1
  • Phosphoric Monoester Hydrolases
  • PTEN Phosphohydrolase
  • PTEN protein, human