Description
FGF4, the product of a developmentally regulated gene (hst1), is a member of the FGF family that is efficiently secreted. The gene for FGF4 (also known as FGFK of KFGF for Kaposi sarcomaassociated FGF) was initially discovered as a transforming gene by the NIH 3T3 focus formation assay using DNA derived from human tumors (including stomach and colon cancers, hepatocellular carcinomas, and Kaposi"s sarcomas). FGF4 does not seem to be expressed in normal adult tissues. However, expression of the gene is spatially and temporally regulated during embryonic development. In vitro, FGF4 is mitogenic for fibroblasts and endothelial cells. FGF4 has been shown to be a potent angiogenesis promoter in vivo. FGF4 has potent transforming potential apparently through an autocrine mechanism of action. FGF4 plays a key role in limb development and has been identified as the molecular mediator of the activities of the apical ectodermal ridge that is required for directing the outgrowth and patterning of vertebrate limbs