Adenosine deaminase activity in a transplantable murine renal adenocarcinoma

Adenosine deaminase (ADA) activity was studied in tumor tissue, spleen, and bone marrow of animals bearing a transplantable murine renal carcinoma. Tumor tissue and splenic ADA specific activities were elevated in these animals when compared to controls although splenic specific activity subsequently declined with increasing tumor burden. Marrow ADA specific activity was the same in tumor bearing animals as in controls regardless of variations in tumor size. Studies of this enzyme may offer insight into salvage pathways of purine biosynthesis thereby suggesting exploitable targets for chemotherapy.