ADA and cancer: To further characterize the effect of 4PYR accumulation on cancer and CP antitumor action, the ATP hydrolysis (ecto-nucleoside triphophate diphosphohydrolase (eNTPD)), AMP hydrolysis (ecto-5′-nucleotidase (e5′NT)), as well as adenosine deamination rate (ecto-adenosine deaminase (eADA)) on the aortas of Control, +CP, +4PYR and +4PYR+CP were measured.