These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Effect of tetrahydrouridine on metabolism and transport of 1-beta-D-arabinofuranosylcytosine in human cells.
    Author: Riva C, Barra Y, Carcassonne Y, Cano JP, Rustum Y.
    Journal: Chemotherapy; 1992; 38(5):358-66. PubMed ID: 1286578.
    Abstract:
    Deamination of cytosine arabinoside (ara-C) by cytidine deaminase is the main mode of inactivation of this drug which can be responsible for ara-C resistance. The present study was undertaken to determine the effect of tetrahydrouridine (THU; a potent inhibitor of cytidine deaminase) on ara-C transport and metabolism in human cells. A rapid transport of ara-C into freshly isolated hepatocytes and an increased intracellular accumulation of the unchanged drug were observed in the presence of 50 micrograms/ml THU. THU inhibited the intracellular deamination of ara-C by 80% and slowed elimination of the compound extracellularly. The intracellular ara-C concentrations achieved after incubation with 1 micrograms/ml ara-C plus 50 micrograms/ml THU are similar to those attained with ara-C (10 micrograms/ml) alone. Treatment of leukemic K562 cells with the combination of THU (50 micrograms/ml) and ara-C (1 micrograms/ml) led to an augmentation of intracellular ara-C triphosphate formation up to twofold.
    [Abstract] [Full Text] [Related] [New Search]