title: Differential transport of cytosine-containing nucleosides by recombinant human concentrative nucleoside transporter protein hCNT1.
abstract: The transportability of cytosine-containing nucleosides by recombinant hCNT1 was investigated in transfected mammalian cells. Apparent K(m) values for hCNT1-mediated transport of uridine, cytidine and deoxycytidine were, respectively, 59, 140 and 150 microM. Uridine transport was inhibited 89, 32 and 11%, respectively, by 500 microM gemcitabine, cytarabine and lamivudine, demonstrating that, unlike gemcitabine (a high-affinity hCNT1 permeant), cytarabine and lamivudine are poor hCNT1 permeants.
authors.affiliation: Department of Oncology, University of Alberta, Cross Cancer Institute, Edmonton, Canada.
authors.forename: K A
authors.initials: KA
authors.lastname: Graham
authors.forename: J
authors.initials: J
authors.lastname: Leithoff
authors.forename: I R
authors.initials: IR
authors.lastname: Coe
authors.forename: D
authors.initials: D
authors.lastname: Mowles
authors.forename: J R
authors.initials: JR
authors.lastname: Mackey
authors.forename: J D
authors.initials: JD
authors.lastname: Young
authors.forename: C E
authors.initials: CE
authors.lastname: Cass
mesh_terms: D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D000998:Antiviral Agents / Q000494:pharmacology; D001692:Biological Transport; D019556:COS Cells; D002352:Carrier Proteins / Q000378:metabolism*; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D003561:Cytarabine / Q000494:pharmacology; D003562:Cytidine / Q000378:metabolism*; D003841:Deoxycytidine / Q000031:analogs & derivatives / Q000378:metabolism* / Q000494:pharmacology; D000882:Haplorhini; D006367:HeLa Cells; D006801:Humans; D015151:Immunoblotting; D019259:Lamivudine / Q000494:pharmacology; D026901:Membrane Transport Proteins; D011994:Recombinant Proteins / Q000378:metabolism; D013379:Substrate Specificity; D014162:Transfection; D014529:Uridine / Q000378:metabolism*; D000093542:Gemcitabine
chemical_list: D000964:Antimetabolites, Antineoplastic; D000998:Antiviral Agents; D002352:Carrier Proteins; D026901:Membrane Transport Proteins; D011994:Recombinant Proteins; C065171:cif nucleoside transporter; D003561:Cytarabine; D003841:Deoxycytidine; D019259:Lamivudine; D003562:Cytidine; D014529:Uridine; D000093542:Gemcitabine