Human Colon Adenocarcinoma Cells. III. In Vitro Organoid Expression and Carcinoembryonic Antigen Kinetics in Hollow Fiber Culture

Cell line LS174T was established in our laboratory from a primary human colon adenocarcinoma and was serially cultured for 4 years. Following 1 month of culture in perfused hollow fiber matrices, organoid growth reminiscent of the patient's original tumor was observed. The cellular organization was predominantly glandular with mucin located within gland lumina and cells. Glands had irregular brush borders, well-developed functional complexes, and intracytoplasmic lumina lined with microvilli, features found in adenocarcinoma tissue. Alternate-day determinations of carcinoembryonic antigen (CEA) revealed bi-phasic kinetics in the extracapillary fluids of the hollow fiber system but not in identically treated monolayer cultures. The initial rate of CEA release was similar to that of monolayer cultures. A significantly accelerated secondary CEA release phase was observed in 10,000- and 50,000-molecular weight (MW)-exclusion fiber cultures (P≤0.001 and P=0.05, respectively). Totals of 43.8 μg and 112.6 μg CEA were released into the extracapillary fluids of 10,000- and 50,000-MW-exclusion fiber cultures, respectively, which were onefold and 2.3-fold increases, respectively, over monolayer supernatant yields. Most CEA was released during the final days of the secondary phase. In monolayer cultures, maximum CEA release occurred during the stationary phase of growth.