Constitutional activation or wild-type MET (a transmembrane tyrosine kinase receptor with a significant role in proliferation, survival, and motility), the receptor for HGF (Hepatocyte Growth Factor) involved in endothelial cell migration, plays a role in the transformation of primary human osteoblasts into osteosarcoma cells; the introduction of dominant-negative MET into osteosarcoma cells reduces in vivo tumorigenesis and transformation [34]. Here, HGF is linked to osteosarcoma.