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Activity of Drug Efflux Transporters in Tumor Cells Under Hypoxic Conditions

  • Oliver Thews
  • Birgit Gassner
  • Debra K. Kelleher
  • Michael Gekle
Part of the Advances In Experimental Medicine And Biology book series (AEMB, volume 614)

Abstract

Tumor cells exhibit mechanisms by which chemotherapeutic drugs can be actively pumped out of the cell (e.g., p-glycoprotein pGP, MRP1), resulting in a multidrug resistant phenotype. Many human tumors show pronounced hypoxia which can result in a local ATP depletion which in turn may compromise the efficacy of these transporters. The aim of this study was therefore to assess the transport activity and expression of drug transporters under hypoxic conditions. Prostate carcinoma cells (R3327-AT1) were exposed to hypoxia (pO2≶0.5 mmHg) for up to 24h and pump activity was determined by an efflux assay. The results showed that exposing cells to hypoxia for 3–6 h led to a moderate increase in pGP activity. After 24 h pGP activity was reduced by 44% compared to control levels. Hypoxia reduced the MRP1 activity to a lesser extent (by 25%). However, the expression of pGP and MRP1 was almost independent of the medium pO2. In conclusion, pronounced hypoxia had only minor effects on the activity of drug transporters with the activity decreasing only after 12–24 h under hypoxia, possibly as a result of ATP depletion. Instead, indirect effects of hypoxia leading to extracellular acidosis seem to have a much more pronounced effect on pGP activity.

Keywords

Hypoxic Condition Ringer Solution Efflux Rate Prostate Carcinoma Cell Glycolytic Metabolism 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    A.H. Schinkel and J.W. Jonker. Mammalian drug efflux transporters of the ATP binding cassette (ABC) family: an overview. Adv. Drug Deliv. Rev. 55, 3–29 (2003).PubMedCrossRefGoogle Scholar
  2. 2.
    S.V. Ambudkar, C. Kimchi-Sarfaty, Z.E. Sauna, and M.M. Gottesman. P-glycoprotein: from genomics to mechanism. Oncogene 22, 7468–7485 (2003).PubMedCrossRefGoogle Scholar
  3. 3.
    T. Fojo and S. Bates. Strategies for reversing drug resistance. Oncogene 22, 7512–7523 (2003).PubMedCrossRefGoogle Scholar
  4. 4.
    M.J. Siegsmund, C. Kreukler, A. Steidler, T. Nebe, K.U. Kohrmann, and P. Alken. Multidrug resistance in androgen-independent growing rat prostate carcinoma cells is mediated by P-glycoprotein. Urol. Res. 25, 35–41 (1997).PubMedCrossRefGoogle Scholar
  5. 5.
    P. Vaupel, F. Kallinowski, and P. Okunieff. Blood flow, oxygen and nutrient supply, and metabolic microenvironment of human tumors: a review. Cancer Res. 49, 6449–6465 (1989).PubMedGoogle Scholar
  6. 6.
    M. Höckel and P. Vaupel. Tumor hypoxia: definitions and current clinical, biological, and molecular aspects. J. Natl. Cancer Inst. 93, 266–276 (2001).PubMedCrossRefGoogle Scholar
  7. 7.
    G. Lee and M. Piquette-Miller. Cytokines alter the expression and activity of the multidrug resistance transporters in human hepatoma cell lines; analysis using RT-PCR and cDNA microarrays. J. Pharm. Sci. 92, 2152–2163 (2003).PubMedCrossRefGoogle Scholar
  8. 8.
    H.H. Versteeg, E. Nijhuis, G.R. van den Brink, M. Evertzen, G.N. Pynaert, S.J. van Deventer, P.J. Coffer, and M.P. Peppelenbosch. A new phosphospecific cell-based ELISA for p42/p44 mitogen-activated protein kinase (MAPK), p38 MAPK, protein kinase B and cAMP-response-element-binding protein. Biochem. J. 350, 717–722 (2000).PubMedCrossRefGoogle Scholar
  9. 9.
    O. Thews, B. Gassner, D.K. Kelleher, G. Schwerdt, and M. Gekle. Impact of extracellular acidity on the activity of p-glycoprotein and the cytotoxicity of chemotherapeutic drugs. Neoplasia 8, 143–152 (2006).PubMedCrossRefGoogle Scholar
  10. 10.
    P. Vaupel, C. Schaefer, and P. Okunieff. Intracellular acidosis in murine fibrosarcomas coincides with ATP depletion, hypoxia, and high levels of lactate and total Pi. NMR Biomed. 7, 128–136 (1994).PubMedCrossRefGoogle Scholar
  11. 11.
    R.H. Xu, H. Pelicano, Y. Zhou, J.S. Carew, L. Feng, K.N. Bhalla, M.J. Keating, and P. Huang. Inhibition of glycolysis in cancer cells: a novel strategy to overcome drug resistance associated with mitochondrial respiratory defect and hypoxia. Cancer Res. 65, 613–621 (2005).PubMedCrossRefGoogle Scholar
  12. 12.
    B.C. Liang. Effects of hypoxia on drug resistance phenotype and genotype in human glioma cell lines. J. Neurooncol. 29, 149–155 (1996).PubMedCrossRefGoogle Scholar
  13. 13.
    K. Sakata, T.T. Kwok, B.J. Murphy, K.R. Laderoute, G.R. Gordon, and R.M. Sutherland. Hypoxia-induced drug resistance: comparison to P-glycoprotein-associated drug resistance. Br. J. Cancer 64, 809–814 (1991).PubMedGoogle Scholar
  14. 14.
    K.M. Comerford, T.J. Wallace, J. Karhausen, N.A. Louis, M.C. Montalto, and S.P. Colgan. Hypoxia-inducible factor-1-dependent regulation of the multidrug resistance (MDR1) gene. Cancer Res. 62, 3387–3394 (2002).PubMedGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Oliver Thews
    • 1
  • Birgit Gassner
    • 2
  • Debra K. Kelleher
    • 1
  • Michael Gekle
    • 2
  1. 1.Institute of Physiology and Pathophysiology, University of MainzGermany
  2. 2.Institute of Physiology, University of WürzburgGermany

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