title: Action of 5-fluorocyclocytidine on cultured L-5178Y cells.
abstract: 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.
mesh_terms: D000818:Animals; D002460:Cell Line; D003561:Cytarabine / Q000031:analogs & derivatives* / Q000494:pharmacology; D004273:DNA, Neoplasm / Q000096:biosynthesis; D003853:Deoxyribonucleosides / Q000494:pharmacology; D007930:Leucine / Q000378:metabolism; D007942:Leukemia, Experimental / Q000188:drug therapy*; D009363:Neoplasm Proteins / Q000096:biosynthesis; D012334:RNA, Neoplasm / Q000096:biosynthesis; D013936:Thymidine / Q000378:metabolism; D014529:Uridine / Q000378:metabolism
chemical_list: D004273:DNA, Neoplasm; D003853:Deoxyribonucleosides; D009363:Neoplasm Proteins; D012334:RNA, Neoplasm; D003561:Cytarabine; D007930:Leucine; D013936:Thymidine; D014529:Uridine