HB-EGF

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a heparin-binding member of the EGF family. It is a potent mitogen and chemotactic factor for fibroblasts and smooth muscle cells. HB-EGF is synthesized as a membrane-anchored form (pro-HB-EGF) that is processed by the ADAM family of metalloproteinases to release soluble mature peptide, which as known as “ectodomain shedding”. It is biologically active either as a pro-HB-EGF or as a soluble form (s-HB-EGF). EGF is expressed in a wide range of cell types, including monocytes/macrophages, CD4+ lymphocytes, neutrophils, eosinophils, myeloid leukemia blasts, myeloma cells, vascular smooth muscle cells, endothelial and normal, or neoplastic epithelial cells. The pro-HB-EGF as a cell-to-cell adhesion protein that exerts mainly inhibitory juxtacrine activities involved in cell cycle arrest and growth inhibition as well as resistance to apoptosis. As a native ligand of EGFR and ErbB4, HB-EGF exerts its activities by binding to its receptors. It is involved in a number of physiological and pathological processes, which include wound healing, cardiac hypertrophy, smooth muscle cell hyperplasia, kidney collecting duct morphogenesis, blastocyst implantation, pulmonary hypertension, and oncogenic transformation.