Amphiregulin (AREG) is a single-pass membrane protein with 252 amino acids. AREG belongs to the amphiregulin family, which contains 1 EGF-like domain. AREG is expressed in a variety of tissues including ovary, placenta, lung, kidney, stomach, colon, and breast. It is related to Epidermal Growth Factor (EGF) and Transforming Growth Factor Alpha (TGF-alpha). As an EGF-related growth factor, AREG interacts with the EGF/TGF-alpha receptor to promote the growth of normal epithelial cells and inhibits the growth of certain aggressive carcinoma cell lines. AREG may also play a protective role in Bleomycin-Induced Pneumopathy.