The Role of Epidermal Growth Factor (EGF)/Transforming Growth Factor (TGF)-α in the Development of Peptic Ulcer Disease, Malignant Tumors and Malignant Ascites.

Growth factors are proteins that modulate cell proliferation and other cellular functions. Many of these factors are polypeptides, and they include epidermal growth factor (EGF) and transforming growth factor (TGF)-α. EGF and TGF-α are members of EGF family, which also contains heparin-binding EGF-like growth factor (HB-EGF), amphiregulin and betacellulin (1, 2). The mature 53-amino-acid EGF is released from the 1,217 amino acid transmembrane precursor by proteolytic cleavage steps. TGF-α mRNA encodes a 160-amino acid transmembrane precursor which contains the mature 50-amino-acid TGF-α. The amino acid sequence homology between EGF and TGF-α is 35%. They both bind to the glycosylated 170-kDa cell surface membrane receptor, and their biological activities are exerted through this receptor. EGF is mainly systhesized by the salivary glands and the kidney (1). TGF-α, on the other hand, was initially thought to be produced by transformed cells and embryonic tissues. However, surveys of TGF-α mRNA expression and protein localization have shown widespread distribution of TGF-α in normal cells and tissues, including activated macrophages, keratinocytes, mammary epithelial cells, the anterior pituitary and most gastrointestinal cells and tissues (2). This report summarizes our studies, which have focused on the role of EGF and TGF-α in the development of diseases, such as peptic ulcer disease, malignant tumors and malignant ascites.

EGF

TGF-α

peptic ulcer diseases

cancer

ascites