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DNA repair: enzymatic mechanisms and relevance to drug response

S G Chaney1, A Sancar

  • 1Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill 27599-7260, USA.

Journal of the National Cancer Institute
|October 2, 1996
PubMed

Insights

Chemotherapy drugs create DNA adducts, leading to cell death. Enhanced DNA repair mechanisms can cause drug resistance, but inhibiting these pathways may restore treatment effectiveness.

Area of Science:

  • Molecular Biology
  • Genetics
  • Pharmacology

Background:

  • Chemotherapeutic agents like platinum drugs, nitrogen mustards, and chloroethylnitrosoureas induce cell death by forming bifunctional DNA adducts.
  • Replication or repair of damaged DNA can lead to chromosome aberrations and cell death.
  • Increased cellular DNA repair capacity is linked to resistance against chemotherapeutic agents.

Purpose of the Study:

  • To review the types of DNA adducts formed by major chemotherapeutic agents.
  • To examine the enzymatic pathways involved in repairing these DNA adducts.
  • To explore the link between enhanced DNA repair and drug resistance.
  • To discuss strategies for overcoming resistance by inhibiting DNA repair.

Main Methods:

  • Literature review of DNA adduct formation by chemotherapeutic agents.
  • Analysis of enzymatic DNA repair pathways.
  • Examination of evidence for enhanced DNA repair in resistant cells and tumors.
  • Review of therapeutic strategies targeting DNA repair inhibition.

Main Results:

  • Chemotherapeutic agents form various bifunctional DNA adducts.
  • Specific enzymatic pathways are responsible for repairing these adducts.
  • Drug-resistant cell lines and tumors exhibit enhanced DNA repair capabilities.
  • Inhibiting DNA repair pathways shows potential for overcoming drug resistance.

Conclusions:

  • DNA adduct formation is a key mechanism of chemotherapy.
  • Enhanced DNA repair is a significant factor in chemotherapeutic resistance.
  • Targeting DNA repair pathways offers a promising strategy to improve cancer treatment efficacy.

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