Role of androgens and fibroblast growth factors in prostatic development.

This review focuses on the role of androgens and fibroblast growth factors (FGFs) in regulating the growth and development of the prostate. It is known that androgens and mesenchymal-epithelial interactions are required for the formation and growth of the prostate, but little is known of the molecular mediators regulating prostatic organogenesis. Paracrine signalling from the mesenchyme to the epithelium is a key element of prostatic development and the action of androgens in mesenchymal cells is essential for prostatic development. This finding has led to the hypothesis that androgens regulate the expression of paracrine-acting growth factors. Although several families of growth factors play a role in regulating prostatic growth, the FGF family contains members that have been studied most comprehensively in regard to prostatic growth and branching morphogenesis. The role of FGFs in prostatic development is described in detail, since two members of the FGF family function as mesenchymal paracrine-acting factors in the prostate. It has been shown that FGF7 and FGF10 play important roles during prostatic development yet they do not appear to be regulated directly by androgens. Current models propose that growth factor expression (including FGF7 and 10) is regulated directly by androgens. However, it is possible that androgen regulation is indirect and a model outlining indirect androgen regulation of growth factors is proposed.