Metabolic changes in liver of tumor-bearing mice

Abstract

The hepatic contents of acetyl coenzyme A, free CoA, α-oxoglutarate, and citrate were determined in tumor-bearing mice. Significant decreases in acetyl CoA and free CoA, with a concomitant increase in citrate occurred 24 hr following inoculation of TLX-5 lymphoma cells. Similar changes occurred in mice bearing a C 3H mammary tumor, when the latter was just palpable in situ. There was some indication that in mice bearing Sarcoma 180, the size of the tumor was a factor in inducing these changes. Significant decreases in the α-oxoglutarate content of liver could only be detected in mice bearing the lymphoma or Sarcoma 180. The direction of change in the hepatic contents of acetyl CoA and citrate were opposite to those found in tumor-free animals under gluconeogenic conditions. However, significant increases in citrate would favor gluconeogenesis by inhibition of phosphofructokinase. Starvation of tumor-bearing mice failed to increase the acetyl CoA content of liver or decrease citrate. The data suggest a failure in lipolysis, as well as in the regulation of fatty acid synthesis in liver via changes in citrate.