A mitogen for hepatocytes (HGF, scatter factor, hepatopoietin A, lung fibroblast-derived mitogen) derived, in the liver, from nonparenchymal cells. It is mitogenic for several cell types and is found in many cells outside the liver, including platelets. HGF is synthesized as a single chain precursor (728 aa) that is cleaved to a heavy chain (463 aa) and a light chain (234 aa) that remain disulphide-linked. Both the uncleaved precursor and the two-chain form of HGF are biologically active and HGF is generally isolated as a mixture of the two forms. HGF also alters cell motility and is identical to scatter factor. The HGF receptor gene, the met oncogene product, is on the same region of chromosome 7 (7q) as HGF itself so that polysomy of chromosome 7 can confer invasive and proliferative capacity through an autocrine effect, and polysomy of chromosome 7 is the most common abnormality in human malignant gliomas. Differentiation of pre-pro-B cells to pro-B cells requires signalling through the IL-7 receptor by IL-7 in association with the β chain of HGF and heparin sulphate. HGF-stimulation of hepatocytes through the MET receptor makes cells susceptible to infection by sporozoites of Plasmodium and damage caused by sporozoite migration causes release of HGF.
Subjects: Medicine and Health.