Summary
Activities of glycolytic enzymes were determined under concordant conditions in a series of rat hepatomas and were compared to normal rat liver. The levels of the activities of certain enzymes were found to divide the hepatomas into 2 groups differing in growth rates. In the more rapidly growing hepatomas the activities of glucokinase, phosphofructokinase, and pyruvate kinase were elevated, whereas fructose diphosphatase, glycerolphosphate dehydrogenase, and phosphoglucomutase activities were drastically decreased. The malate dehydrogenases were also substantially reduced, but considerable enzymic activity still remained. These changes tend to diminish some of the specialized functions of normal liver and can be viewed as a graded dedifferentiation of the tissue.
This investigation was supported by the Cancer Chemotherapy National Service Center, National Cancer Institute, under the NIH contract No. SA-43-ph-1886.