EGF receptor signaling in prostate morphogenesis and tumorigenesis

The growth and differentiation of the prostate gland are largely dependent on extracellular signaling factors. In addition to androgens, many polypept ide growth factors function through autocrine or paracrine networks. The pa racrine interaction between stromal and epithelial cells is critical for an drogen regulation, morphogenesis, epithelial cell proliferation, and secret ory differentiation. Efforts to identify the essential growth factors and s tudies on their effects have been prompted by the fact that prostate cells in culture need substances other than androgens for proliferation. In this context, transforming growth factor-a and epidermal growth factor, among ot hers, have been studied extensively. Recent advances have suggested that th ese EGF receptor (EGFR) ligands play roles not only during glandular develo pment but also during neoplastic transformation and tumor progression. The cell responses most relevant to the role of this receptor signaling are bot h mitogenesis and cell motility. The aim of the review is to provide an ove rview of current knowledge about EGFR and its ligands in the organogenesis and tumorigenesis of the prostate gland.