Culture of low passage colorectal cancer cells and demonstration of variation in selected tumour marker expression.

There is increasing evidence that a tumour comprises of heterogeneous population of cells. Thus, studying homogenous cell lines in vitro may yield results that are not reflective of the true situation in a tumour and studying low passage cell lines maintained in a heterogeneous population before they transform away from the original state may provide a more complete picture of colorectal cancer. A method was developed to isolate and establish low passage colorectal cancer cell lines from tumour biopsies. The media contents, combination of antimicrobials and specimen collection and transport conditions employed, successfully eliminated microbial contamination which is frequently present in samples obtained from the gastrointestinal tract. A variety of growth forms indicating a heterogeneous mixture of cells was seen in the initial cultures. Using fluorescence immunocytochemistry, primary tumour cultures were shown to variably express selected tumour markers, carcinoembryonic antigen and C2 antigen. These low passage cell lines growing in a heterogeneous environment would more closely reflect the characteristics of the cells of the original tumour.