ABSTRACT
This chapter suggests that judicious selection of the target cell population and specific maturation "markers" may minimize this ambiguity in differentiation status. Certain human colon carcinoma cells, undergo specific biochemical, functional, and cytoarchitectural transitions over the course of induced or spontaneous in vitro and in vivo enterocyte maturation. The HT-29 human colonic adenocarcinoma cell line is one such candidate. HT-29 is a relatively undifferentiated tumor cell type inducible to a more mature by exposure to specific differentiation-inducing agents such as sodium-n-butyrate (NaB). The active form of vitamin D3, 1,25-dihydroxyvitamin D3, exerts varied pharmacologic actions through a hormone-receptor complex that mediates changes in gene expression in target tissues. NaB, a product of intestinal bacterial flora, induces maturation of certain colorectal cancer cells, including the HT-29 line. The extent of HT-29 cell differentiation can be quantitatively assessed using biochemical, functional, and morphologic criteria associated with colonocytic differentiation.
