The Role of Membrane Transporters in Cellular Resistance to Anticancer Nucleoside Drugs

  • Marilyn L. Clarke
  • John R. Mackey
  • Stephen A. Baldwin
  • James D. Young
  • Carol E. Cass
Part of the Cancer Treatment and Research book series (CTAR, volume 112)


Physiologic nucleosides and most therapeutic nucleoside analogs do not readily cross plasma membranes by passive diffusion due to their low solubility in lipid bilayers, and their cellular uptake is mediated by integral membrane proteins. Nucleoside transporters serve as the cellular entry point for nucleoside salvage pathways. Some cell types use these pathways exclusively because they lack the ability to synthesize purine and pyrimidine nucleotides. Other cell types use salvage pathways in addition to their de novo synthesis pathways. Nucleotides are key activated intermediates for many essential cellular biosynthetic pathways, including the synthesis of DNA and RNA


Nucleoside Analog Purine Nucleoside Nucleoside Transporter Pyrimidine Nucleoside Deoxycytidine Kinase 
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Copyright information

© Springer Science+Business Media New York 2002

Authors and Affiliations

  • Marilyn L. Clarke
    • 1
  • John R. Mackey
    • 1
    • 2
    • 6
  • Stephen A. Baldwin
    • 3
  • James D. Young
    • 4
  • Carol E. Cass
    • 1
    • 5
    • 6
  1. 1.Departments of Experimental OncologyCanada
  2. 2.Department of MedicineCross Cancer InstituteEdmontonCanada
  3. 3.School of Biochemistry and Molecular BiologyUniversity of LeedsLeedsUK
  4. 4.Department of PhysiologyUniversity of AlbertaEdmontonCanada
  5. 5.Department of BiochemistryUniversity of AlbertaEdmontonCanada
  6. 6.Department of OncologyUniversity of AlbertaEdmontonCanada

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