The receptor for the type I insulin-like growth factor and its ligands regulate multiple cellular functions that impact on metastasis.

The receptor for the type I insulin-like growth factor (IGF-IR) has been identified as a regulator of cellular transformation and the acquisition of the tumorigenic phenotype. This article reviews recent evidence including the authors' own, which implicates this receptor and its ligands IGF-I and IGF-II in the regulation of multiple cellular functions that impact on the invasive/metastatic potential of cancer cells. These include cell survival, motility, invasion, growth potential in secondary organ sites, the induction of angiogenesis, and the acquisition of multiple drug-resistance. Collectively, this evidence identifies the IGF-I receptor/ligand system as a target for molecular anti-cancer therapy with potential benefits for a wide spectrum of human malignancies.