transforming growth factor
A family of growth factors secreted by transformed cells that induce the phenotypic characteristics of cell transformation (e.g. the ability to grow in semisolid agar), but do not cause hereditable changes. TGFα (50 aa) binds to the EGF receptor and will stimulate the growth of microvascular endothelial cells. TGFβ is a homodimer (two 112 aa chains) secreted by many different cell types and a growth inhibitor for some cell types. Mutations in TGFβ cause Camurati–Engelmann disease. The TGF family includes many of the bone morphogenetic proteins (BMPs). See activin; syndecans.