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Mechanisms of resistance to topoisomerases poisons

S Prost1

  • 1Cancer Research Campaign Laboratories, Department of Pathology, University Medical School, Edinburgh, UK.

General Pharmacology
|December 1, 1995
PubMed

Insights

Drug resistance is a significant challenge in cancer therapy. This review examines DNA topoisomerase (Topo) inhibitors and the mechanisms behind multidrug resistance in cancer treatment.

Area of Science:

  • Oncology
  • Molecular Biology
  • Biochemistry

Background:

  • Drug resistance is a primary obstacle in effective cancer chemotherapy.
  • Resistance can be intrinsic (initial non-responsiveness) or acquired (relapse after treatment).
  • Cross-resistance to structurally different drugs often accompanies single-agent resistance.

Purpose of the Study:

  • To review the cellular functions and catalytic activities of DNA topoisomerases (Topos).
  • To elucidate the mechanisms of resistance to Topo inhibitors.
  • To focus on the atypical multidrug resistance phenotype associated with Topo inhibition.

Main Methods:

  • Literature review of studies on DNA topoisomerases and drug resistance.
  • Analysis of cellular functions and enzymatic activities of Topos.
  • Examination of resistance mechanisms, including multidrug resistance.

Main Results:

  • DNA topoisomerases are critical enzymes regulating DNA topology and essential cellular processes.
  • Inhibitors of Topos are widely used in cancer chemotherapy.
  • Atypical multidrug resistance phenotypes are associated with resistance to Topo inhibitors.

Conclusions:

  • Understanding Topoisomerase functions and resistance mechanisms is crucial for overcoming chemotherapy failure.
  • Targeting Topoisomerases remains a key strategy in cancer treatment.
  • Further research into multidrug resistance is necessary to improve patient outcomes.

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