Experimental cancer therapy in mice by adenine nucleotides.

Adenosine 5'-monophosphate (AMP), adenosine 5'-diphosphate (ADP) and adenosine 5'-triphosphate (ATP), injected intraperitoneally into tumor-bearing (s.c. implanted footpad tumors) mice, exhibited significant anticancer activity. Daily treatments (for 10 days) inhibited the growth of the fast-growing, aggressive CT 26 colon adenocarcinoma in CB6F1 mice. The growth-inhibitory activity of adenine nucleotides was also observed against a human pancreatic adenocarcinoma, CAPAN-1, xenografts in athymic nude mice. With low tumor burdens some 'cures' were obtained in both model systems. No inherent toxicity, as determined by changes in host weight, were observed during and after the period of treatment. Intraperitoneal injections of 1 ml of 50 mM AMP, ADP or ATP in saline, yielded elevated blood and plasma levels of ATP which lasted for several hours in both strains of mice. The growth-inhibitory activities of adenine nucleotides against tumor cells in vitro, have previously been demonstrated.