IGF-IR and its inhibitors in gastrointestinal carcinomas (Review).

The type I insulin-like growth factor receptor (IGF-IR) and its associated signaling system play a significant role in tumorigenesis, tumor survival and progression, and cancer therapeutic resistance, and thus has provoked great interest as a promising target for cancer treatment. In this report we present the role of IGF-IR in gastrointestinal carcinomas whose pathology has been identified as tightly correlated with an abnormal expression and activation of IGF-IR. Reported data from experimental studies suggest the feasibility of targeted IGF-IR therapy in gastrointestinal carcinomas. Many types of inhibitors against IGF-IR have been developed. Inhibitors with anti-IGF-IR monoclonal antibodies and tyrosine kinase inhibitors currently undergoing preclinical and clinical evolution are also reviewed.