Effects of high dose ascorbate administration on L-10 tumor growth in guinea pigs.
Sodium ascorbate is preferentially toxic to tumor cells at high concentrations. It has not been established, however, whether sufficient intra-tumor ascorbate concentrations are safely achievable in vivo. We administered sodium ascorbate subcutaneously or orally for eighteen days to Sewall-Wright strain-2 guinea pigs bearing intradermal L-10 hepatocarcinoma tumors. Tumor masses and intra-tumor ascorbate concentrations were determined at necropsy. L-10 cells formed tumors that metastasized to the lymph nodes, with tumor burdens reaching nearly 50 grams in untreated animals. Subcutaneous injections of ascorbate (500 mg/kg/day) inhibited tumor growth by as much as sixty-five percent, with oral supplementation reducing it by roughly fifty percent. Tumor growth correlated inversely with intra-tumor ascorbate concentration, the latter exceeding 2 mM in some cases. Ascorbate concentrations sufficient to kill tumor cells can be safely achieved in solid tumors in vivo, suggesting a possible role for high dose intravenous ascorbate in treating cancer.
Casciari
Joseph J
JJ
Center for the Improvement of Human Functioning, Bio-communications Research Institute, 3100 N Hillside Avenue, Wichita, KS 67219, USA.
Riordan
Hugh D
HD
Miranda-Massari
Jorge R
JR
Gonzalez
Michael J
MJ
D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage* / Q000032:analysis; D001205:Ascorbic Acid / Q000008:administration & dosage* / Q000032:analysis; D048708:Cell Growth Processes / Q000187:drug effects; D045744:Cell Line, Tumor / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006168:Guinea Pigs; D008114:Liver Neoplasms, Experimental / Q000188:drug therapy
D000975:Antioxidants; D001205:Ascorbic Acid