Role of epidermal growth factor in carcinogenesis.

For cell growth and division to occur, a large variety of metabolic processes must be carefully coordinated in the cell. Through evolutionary pressures, specific hormones and growth factors have acquired the ability to trigger a complex coordinated "pleiotropic growth response" in their target cells. This complex response is mediated by specific cellular receptors and intracellular messengers. Teleologically then, it makes sense that in oncogenesis this growth regulating network is utilized by the production of proteins which mimic growth factors, the activated form of their receptors or, the messengers themselves. Several lines of evidence indicate that the epidermal growth factor-stimulated growth regulatory system is involved in cellular proliferation, both normal and neoplastic. Some of the effects of epidermal growth factor in carcinogenesis are separable from its direct, growth stimulatory effects. Thus, the role of epidermal growth factor in carcinogenesis is more complex than is its role in stimulating growth.