The role of insulin-like growth factors in prostate biology.

Insulin-like growth factors (IGFs) are critical regulators of cell and tissue growth. Acting by endocrine as well as paracrine and autocrine mechanisms, the IGFs play unique roles in each organ or tissue. These unique roles of IGFs are in part mediated by the interrelated components of the greater IGF system, which includes IGF receptors, IGF-binding proteins (IGFBPs), receptors for IGFBPs, and IGFBP proteases (Cohick and Clemmons, 1993). The specific pattern of components present at any given time determines the overall impact of the IGFs at that specific site. Recently, we and others have become interested in characterizing the components of the IGF system in the prostate and in developing a model for the role of IGFs in normal prostate biology, in benign prostatic hyperplasia (BPH), and in prostate cancer. This minireview will summarize our present understanding of the IFG system in the prostate; current data suggest that IGFs are important elements in the development of BPH and cancer.