[Changes in several properties of transplantable adenocarcinoma of the large intestine during passage]

In the course of serial passages of adenocarcinoma (AKTOL), arising from fetal colonic tissues which underwent spontaneous malignization after being grafted to syngeneic adult mice, there was an increase in the rate of growth of the subcutaneous transplants, and multiple intrapulmonary tumour nodes formed after its intravenous inoculation (the first transplant generations had no such capacity); the morphological anaplasia of the tumour increased. These changes were not directly dependent on the changes in its immunogenicity.