The antagonistic activity exerted by thymine and folic acid on the inhibiting action of 2-thio-5-methylcytosine on the growth of mouse Ehrlich adenocarcinoma has been studied. Results are referred. Emphasis is laid on the biphasic action (antagonistic at low doses and synergic at high doses) elicited by the two metabolites towards the pyrimidine analog. Some hypotheses on the mechanism of such antagonistic action are advanced. Results « in vivo » are compared with those observed in microbiological systems and in cultures from chicken embryo fibroblasts.
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References
1.
BoylandE., Cancer Research, 12, 77, 1952.
2.
BrownJ. B., RollP. M., e WeinfieldH., Phosphorus Metabolism, Mc Elroy & Glass Editors, Johns Hopkins Press, Baltimore, 1952, pag. 388.
3.
Di MarcoA., e GaetaniM., Tumori, 42, 531, 1956 (a).
4.
Di MarcoA., GhioneM., e SanfilippoA., Giorn. Microbiol., 4, 323, 1956 (b).
5.
Di MarcoA., GhioneM., e SanfilippoA., in corso di pubblicazione.
6.
Di MarcoA., e NeccoA., Tumori, 42, 519, 1956 (c).
7.
HitchingsG. H., e FalcoE. A., ElionG. B., J. Biol. Chem., 185, 643, 1950.
8.
HolmesW. L., PrusoffW. H., e WelchA.D., J. Biol. Chem., 209, 503, 1954.
9.
PhilipsF. S., ThierschJ. B., e FergusonF. C., Ann. N. Y. Acad. Sc., 52, 1349, 1950.
10.
PlentlA. A., e SchoenheimerR., J. Biol. Chem., 153, 203, 1944.
