Inhibition of transplantable melanoma tumor development in mice by prophylactic administration of Ca-ascorbate.
Hemicalcium ascorbate (Ca-Asc, 51 mM, 1% wt/vol), added to the drinking water, had the following effects in DBA/2 mice inoculated with 10(5) S91 (Cloudman) melanoma cells: 1) it delayed the appearance of visible tumors by 2-4 weeks; 2) it increased the survival rate at three months after tumor challenge by 12-50%; 3) it had no significant effect on the rate of tumor growth once the size of the tumors had reached 10 mm3; 4) the inhibition was maximal when the treatment with Ca-Asc was started at least one week prior to the inoculation of cells 5) when free ascorbic acid was used instead of Ca-Asc, the animals consumed 50% less water, they became dehydrated and the treatment was less effective; 6) Ca++ (51 mM) alone had no significant inhibitory effect.--Since Ca Asc (1 mM) was not toxic to S91 melanoma cells in vitro, we suggest that prophylactic treatment of the animals with Ca-Asc inhibited tumor development by increasing the resistance of the host.
D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology / Q000627:therapeutic use*; D002118:Calcium / Q000494:pharmacology / Q000627:therapeutic use*; D002455:Cell Division / Q000187:drug effects; D003300:Copper / Q000494:pharmacology; D005260:Female; D008545:Melanoma / Q000188:drug therapy*; D051379:Mice; D008811:Mice, Inbred DBA; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000188:drug therapy; D013997:Time Factors
D003300:Copper; D001205:Ascorbic Acid; D002118:Calcium