Accumulation of polycyclic aromatic hydrocarbon-induced single strand breaks is attributed to slower rejoining processes by DNA polymerase inhibitor, cytosine arabinoside in CHO-K1 cells

Life Sci. 1991;48(13):1255-61. doi: 10.1016/0024-3205(91)90520-l.

Abstract

We demonstrate a successful induction of DNA single strand breaks in CHO-K1 cells by cocultivation with mouse embryonic fibroblasts (MEF) during exposure to benzo(a)pyrene (BP) or 3-methylcholanthrene (MC). When compared to those induced by methyl methanesulfonate (MMS), the DNA single strand breaks induced by BP and MC were markedly accumulated by post-incubation with cytosine arabinoside (araC) and were much more delayed in their rejoining. These results suggest that the active metabolites of BP or MC produced by cocultivation with MEF or microsomal fraction (S-15) result in the formation of large DNA adducts which require an active participation of DNA polymerase alpha(delta) in the polymerization step of excision repair for their removal.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Fractionation
  • Cells, Cultured
  • Cricetinae
  • Cricetulus
  • Cytarabine / pharmacology*
  • Cytarabine / toxicity
  • DNA Damage*
  • DNA Polymerase II / antagonists & inhibitors*
  • DNA Repair / drug effects*
  • Fibroblasts / cytology
  • Methyl Methanesulfonate / toxicity
  • Mice
  • Polycyclic Compounds / toxicity*

Substances

  • Polycyclic Compounds
  • Cytarabine
  • Methyl Methanesulfonate
  • DNA Polymerase II