[Alteration of phenotype, morphology and drug sensitivity in colon cancer cell lines under various culture conditions].

Thirteen colorectal cancer cell lines were established from 120 fresh colon cancer specimens. Expression of colon cancer-related antigens and blood group-related antigens on these cell lines were evaluated by Mixed Hemadsorption test (MHA) and Immune Adherence test (IA). The results were compared with the results of immunohistological analysis of the antigen expression in sections of the original tissues, and deletions of several blood group-related antigens in cell lines were observed. Colon cancer cell line HT-29, cultured in different lots of FCS or in different types of serum-free medium showed various antigen expression, suggesting the effect of culture medium on phenotypic expression. In glucose-free medium, HT-29 cells showed the characteristic "dome formation" which is typical of enterocytic differentiation forming brush borders in such cells. HT-29 cells cultured on bovine corneal endothelial extracellular matrix (BCE-ECM) coated plates showed similar enterocytic changes under phase-contrast microscope. Also, irradiated HT-29 cells cultured under 8-Azaguanine containing medium retained their strong resistance to 8-Azaguanine. These results suggest that these cancer cell lines might alter their phenotype, morphology, differentiation, growth pattern and drug sensitivity depending on the culture environment.