| Literature DB >> 2069845 |
J Zittoun1, J Marquet, J J Pilorget, C Tonetti, E De Gialluly.
Abstract
The comparative efficacy of the pure diastereoisomers of leucovorin, the natural (6S) and the unnatural (6R) forms was compared to the racemic form (6RS). A protective effect in methotrexate-treated CCRF-CEM cells was obtained with 6S at concentrations 100-fold higher than those of methotrexate and with 6RS at concentrations 2-fold greater than those of 6S; however, at low concentrations of methotrexate, 6S was more effective than 6RS in preventing the cytotoxicity of methotrexate; on the opposite, 6R exhibited a protective effect at concentrations 10(4) higher than those of methotrexate. On the same cell line, 6S was shown to enhance the cytotoxic effect of 5 Fluorouracil exactly as 6RS while 6R did not exhibit any enhancing effect on cells exposed to 5 Fluorouracil.Entities:
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Year: 1991 PMID： 2069845 PMCID： PMC1972534 DOI： 10.1038/bjc.1991.194
Source DB: PubMed Journal: Br J Cancer ISSN： 0007-0920 Impact factor: 7.640