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Epidermal Growth Factor （EGF） is a potent growth factor that stimulates the proliferation of various epidermal and epithelial cells. EGF binds to epidermal growth factor receptor and stimulates an intracellular signal transduction cascade, leading to activation of genes that regulate cell proliferation, angiogenesis, motility, and metastasis. EGF mRNA and protein are expressed in a number of adult tissues, especially in epithelial cells in the gastrointestinal tract. Predominant sites of synthesis of this peptide are the submandibular glands, the Brunner glands in the small intestine and the kidney.