bottom-up model


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bottom-up model

One of two proposed mechanisms of spontaneous gastrointestinal tract adenomas. In the bottom up model, a stem cell situated in the base of a crypt acquires mutations in the adenomatous polyposis coli (APC) tumour-suppressor gene, impairing the function of the APC protein. The bottom-up theory holds that adenomas, both familial/hereditary and sporadic, arise from a monoclonal proliferation in the gland crypts (monocryptal adenoma), followed by the multistep process of carcinogenesis.