Mutant p53 cooperates with ETS2 to promote etoposide resistance

Genes Dev. 2012 Apr 15;26(8):830-45. doi: 10.1101/gad.181685.111.

Abstract

Mutant p53 (mtp53) promotes chemotherapy resistance through multiple mechanisms, including disabling proapoptotic proteins and regulating gene expression. Comparison of genome wide analysis of mtp53 binding revealed that the ETS-binding site motif (EBS) is prevalent within predicted mtp53-binding sites. We demonstrate that mtp53 regulates gene expression through EBS in promoters and that ETS2 mediates the interaction with this motif. Importantly, we identified TDP2, a 5'-tyrosyl DNA phosphodiesterase involved in the repair of DNA damage caused by etoposide, as a transcriptional target of mtp53. We demonstrate that suppression of TDP2 sensitizes mtp53-expressing cells to etoposide and that mtp53 and TDP2 are frequently overexpressed in human lung cancer; thus, our analysis identifies a potentially "druggable" component of mtp53's gain-of-function activity.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Cell Line, Tumor
  • DNA-Binding Proteins
  • Drug Resistance, Neoplasm*
  • Etoposide / pharmacology*
  • Humans
  • Lung Neoplasms / genetics
  • Lung Neoplasms / metabolism*
  • Mutation
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Phosphoric Diester Hydrolases
  • Proto-Oncogene Protein c-ets-2 / metabolism*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism*

Substances

  • Antineoplastic Agents, Phytogenic
  • DNA-Binding Proteins
  • ETS2 protein, human
  • Nuclear Proteins
  • Proto-Oncogene Protein c-ets-2
  • Transcription Factors
  • Tumor Suppressor Protein p53
  • Etoposide
  • Phosphoric Diester Hydrolases
  • TDP2 protein, human