Cultural and Antigenic Properties of Newly Established Cell Strains Derived From Adenocarcinomas of the Human Colon and Rectum

Two strains of neoplastic cells were established from adenocarcinomas of the human lower gastrointestinal tract. Both strains, human colon tumor-8 (HCT-8) and human rectal tumor-18 (HRT-18), grew as discrete and tightly packed colonies of epithelial cells, each with a large nucleus and scanty cytoplasm. Fairly uniform microvilli, disposed over the entire free surface of the cells, were frequently parallel, closely resembling the brush border of the intestinal epithelial cells. The strains were characterized by a short generation time and high plating efficiency. The cells formed colonies when plated on human fibroblasts but did not form colonies on fibroblasts from other species. Cytogenetic analysis of HCT-8 revealed a mode of 48 chromosomes at both low and high in vitro passage levels, with extra A and D chromosomes in approximately 90%. HRT-18 also had a mode of 48 chromosomes. However, the additional chromosomes were more random, appearing for the most part in groups D and F. Both HCT-8 and HRT-18 yielded high levels of carcinoembryonic antigen (CEA) in vitro, with most CEA in the culture supernatant and not cell associated.