Action of 5-fluorocyclocytidine on cultured L-5178Y cells
Yoshida, M.; Hoshi, A.; Kuretani, K.; Kanai, T.; Ichino, M.
Gan 66(5): 561-564
1975
ISSN/ISBN: 0016-450X PMID: 1240808 Document Number: 86939
Effect of substitution of 5-position of cyclocytidine with fluorine on its antitumor activity in cultured cells was examined. 5-Fluorocyclocytidine was active against cultured L-5178Y cells similar to cyclocytidine. IC50 of the compound was 0.054 mug/ml. This compound inhibited thymidine incorporation into acid-soluble fraction of the cells. Cell growth inhibition by 5-fluorocyclocytidine was reversed by deoxycytidine but not by thymidine and deoxyuridine. On the other hand, cell growth inhibition by 5-fluorouracil was reversed by thymidine and deoxyuridine. As a result, site of action of 5-fluorocyclocytidine was considered to be similar to that of cyclocytidine and not to 5-fluorouracil.