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The great multidrug-resistance paradox

Vivien Y Chen1, Gus R Rosania

  • 1Department of Pharmaceutical Sciences, University of Michigan College of Pharmacy, 428 Church Street, Ann Arbor, Michigan 48109, USA.

ACS Chemical Biology
|December 14, 2006
PubMed

Insights

Multidrug resistance in cancer cells is not solely due to drug efflux pumps. Intracellular drug sequestration within organelles explains high drug levels in resistant cells, offering new therapeutic strategies.

Area of Science:

  • Pharmacology
  • Cancer Biology
  • Cellular Mechanisms

Background:

  • Traditional research on multidrug resistance (MDR) in tumor cells primarily focused on transmembrane drug transporters responsible for extruding drugs from the cell.
  • This efflux mechanism alone fails to explain the high intracellular drug concentrations observed in many drug-resistant cancer cells.

Discussion:

  • Recent studies highlight the critical role of intracellular drug sequestration within cytoplasmic organelles as a key mechanism contributing to MDR.
  • This sequestration can maintain high intracellular drug levels despite active efflux, resolving paradoxical observations in resistant cell lines.

Key Insights:

  • Drug sequestration in organelles is a significant factor in overcoming cancer cell multidrug resistance.
  • Understanding cellular pharmacokinetics, including organelle sequestration, is crucial for developing effective cancer therapies.

Outlook:

  • Exploiting cellular pharmacokinetic properties, such as organelle sequestration, offers a promising avenue for developing targeted therapies against drug-resistant cancers.
  • Future research should focus on modulating organelle drug accumulation to re-sensitize resistant tumors to chemotherapy.

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