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Carcinogenesis in gastrointestinal organs

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Part of the book series: Cancer Treatment and Research ((CTAR,volume 33))

Abstract

Concepts of carcinogenesis are evolving rapidly and have been refined into a multistep or multistage scheme during the past few decades. Longer reviews of progress in experimental carcinogenesis summarize the basis for these concepts which are derived from studies in many tissues and species, both in vivo and in vitro. The initiating event (initiation) of carcinogenesis is generally regarded as an early and probably irreversible effect of a carcinogen on a cell. It appears that alteration in the function of critical gene products and/or contrql of expression of cellular genes occur as a result of initiation. Such alterations start a series of changes in the initiated cell that may ultimately culminate in the development of a neoplastic phenotype, i.e. uncontrolled growth and perhaps the ability to invade and metastasize. These changes are commonly accompanied by some degree of loss of cell differentiation.

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Longnecker, D.S., Michalopoulos, G.K., Osborne, J.W. (1987). Carcinogenesis in gastrointestinal organs. In: MacDonald, J.S. (eds) Gastrointestinal Oncology. Cancer Treatment and Research, vol 33. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-2031-9_1

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