Sequential analysis of transplantable hepatocellular carcinomas.

In a previous study multiple characteristics of chemically induced primary hepatocellular carcinomas were described and examined during the initial transplant generations. The present communication reports on these characteristics in subsequent transplant generations followed over a 2-year period. In almost all instances the growth rate, morphology, chromosome composition, and plasma protein and alpha-fetoprotein synthesis of individual tumors have remained relatively constant. However, one spontaneous subline of a diploid tumor demonstrated a sudden extensive rearrangement of its chromosomes simultaneous with a significant acceleration of growth rate. Despite karyotypic evolution, it retained the functional characteristics of diploid tumors, producing no plasma protein or alpha-fetoprotein.