TGFB1 (Transforming Growth Factor β1) encodes a secreted ligand of the TGF-β superfamily. The protein has the function of regulating cell proliferation, differentiation and growth. Many cells synthesize TGFB1 and have specific receptors. This gene can regulate the expression and activation of other growth factors, including interferon gamma and tumor necrosis factor alpha. It plays an important role in bone remodeling because it is a potent stimulator of osteoblastic bone formation, causing chemotaxis, proliferation and differentiation in committed osteoblasts. This gene often up-regulates expression in tumor cells and its mutations lead to Camurati-Engelmann disease. Its related pathways are response to platelet cytosolic Ca2+ and transcriptional androgen receptor nuclear signaling.