Corpus ID: 31834009

Tiazofurin metabolism in human lymphoblastoid cells: evidence for phosphorylation by adenosine kinase and 5'-nucleotidase.

@article{Fridland1986TiazofurinMI,
  title={Tiazofurin metabolism in human lymphoblastoid cells: evidence for phosphorylation by adenosine kinase and 5'-nucleotidase.},
  author={Arnold Fridland and Michele C. Connelly and T J Robbins},
  journal={Cancer research},
  year={1986},
  volume={46 2},
  pages={
          532-7
        }
}
The exact route of metabolism of tiazofurin, a novel nucleoside with antitumor activity, is controversial. Using human cell lines severely deficient in salvage nucleotide enzymes, we were able to identify the route of activation in tiazofurin metabolism. With loss of adenosine kinase activity by mutation in two lymphoblastoid cell lines, CCRF-CEM and WI-L2, the growth sensitivity to tiazofurin decreased by 6- and 3-fold, respectively. In contrast, the mutant lines were about 3000- to 1500- and… Expand
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TLDR
In CHO cells, tiazofurin is more toxic than ribavirin and also demonstrates a stronger inhibition of guanine nucleotide synthesis, suggesting that the inhibition is due, at least in part, to guanylate deficiency. Expand
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TLDR
2-beta-D-Ribofuranosyl-4-selenazolecarboxamide, the selenium analog of tiazofurin, was 3- to 10-fold more cytotoxic to murine or human tumor cells in vitro than tiaz ofurin and was also more active against P388 mouse leukemia in vivo. Expand
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