Targeting OGG1 arrests cancer cell proliferation by inducing replication stress

Nucleic Acids Res. 2020 Dec 2;48(21):12234-12251. doi: 10.1093/nar/gkaa1048.

Abstract

Altered oncogene expression in cancer cells causes loss of redox homeostasis resulting in oxidative DNA damage, e.g. 8-oxoguanine (8-oxoG), repaired by base excision repair (BER). PARP1 coordinates BER and relies on the upstream 8-oxoguanine-DNA glycosylase (OGG1) to recognise and excise 8-oxoG. Here we hypothesize that OGG1 may represent an attractive target to exploit reactive oxygen species (ROS) elevation in cancer. Although OGG1 depletion is well tolerated in non-transformed cells, we report here that OGG1 depletion obstructs A3 T-cell lymphoblastic acute leukemia growth in vitro and in vivo, validating OGG1 as a potential anti-cancer target. In line with this hypothesis, we show that OGG1 inhibitors (OGG1i) target a wide range of cancer cells, with a favourable therapeutic index compared to non-transformed cells. Mechanistically, OGG1i and shRNA depletion cause S-phase DNA damage, replication stress and proliferation arrest or cell death, representing a novel mechanistic approach to target cancer. This study adds OGG1 to the list of BER factors, e.g. PARP1, as potential targets for cancer treatment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antineoplastic Agents / chemical synthesis
  • Antineoplastic Agents / pharmacology
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Colonic Neoplasms / drug therapy*
  • Colonic Neoplasms / genetics
  • Colonic Neoplasms / metabolism
  • Colonic Neoplasms / mortality
  • DNA Damage
  • DNA Glycosylases / antagonists & inhibitors
  • DNA Glycosylases / genetics*
  • DNA Glycosylases / metabolism
  • DNA Repair / drug effects
  • DNA Replication / drug effects
  • DNA, Neoplasm / genetics*
  • DNA, Neoplasm / metabolism
  • Enzyme Inhibitors / chemical synthesis
  • Enzyme Inhibitors / pharmacology
  • Gene Expression Regulation, Neoplastic*
  • Guanine / analogs & derivatives
  • Guanine / metabolism
  • HCT116 Cells
  • Humans
  • Mice
  • Mice, Nude
  • Molecular Targeted Therapy
  • Oxidative Stress
  • Poly (ADP-Ribose) Polymerase-1 / immunology*
  • Poly (ADP-Ribose) Polymerase-1 / metabolism
  • RNA, Small Interfering / genetics
  • RNA, Small Interfering / metabolism
  • Reactive Oxygen Species / antagonists & inhibitors
  • Reactive Oxygen Species / metabolism
  • Signal Transduction
  • Survival Analysis
  • Tumor Burden / drug effects
  • Xenograft Model Antitumor Assays

Substances

  • Antineoplastic Agents
  • DNA, Neoplasm
  • Enzyme Inhibitors
  • RNA, Small Interfering
  • Reactive Oxygen Species
  • 8-hydroxyguanine
  • Guanine
  • PARP1 protein, human
  • Poly (ADP-Ribose) Polymerase-1
  • DNA Glycosylases
  • oxoguanine glycosylase 1, human