Background:

Fibroblast growth factor 20 (FGF-20) is a secreted heparin binding growth factor and member of the FGF family. Proteins of this family play a central role during prenatal development, postnatal growth and regeneration of a variety of tissues, by promoting cellular proliferation and differentiation (1). FGF-20 is most similar to FGF-9 and FGF-16. It signals through a variety of FGF receptors and is known to bind to heparin. FGF-20 is expressed in normal brain, particularly the cerebellum, and in some cancer cell lines. It is expressed preferentially in the substantia nigra pars compacta of the rat brain (2). Expression of FGF-20 and DKK-1 is regulated by β-catenin during development and tumorigenisis, implying that FGF-20 may play a role in the oncogenisis induced by the Wnt signaling pathway (3). In NIH 3T3 cells, FGF-20 expression causes a transformed phenotype and these transformed cells are tumorigenic in nude mice (4). Recombinant rat FGF-20 is one of the neurotrophic factors, which enhances the survival of midbrain dopaminergic neurons in vitro. It has been demonstrated to possess therapeutic activity in two experimental models of intestinal inflammation (4).