The IGF/IGF-I receptor signaling pathway as a potential target for cancer therapy

Expression of insulin-like growth factors (IGFs) and their cognate receptor,tbe IGF-I receptor, is frequently upregulated during the development of many types of cancer. Besides stimulating cell cycle progression and the transformation status of tumor cells, a wealth of recent experimental data suggests that IGF-mediated signaling exerts a central tumor-promoting function through the repression of tumor cell apoptosis. These functions are all conveyed by the IGF-I receptor, thus making it an attractive target for therapeutic intervention. Notably, inhibition of IGF-mediated survival function appears to synergize with conventional chemotherapeutic ablation of tumor cells, raising the possibility of combinatorial cancer therapies with significantly reduced side-effects.