Functional analysis of the EWS/ETS target gene uridine phosphorylase

Cancer Res. 2003 Jul 15;63(14):4268-74.

Abstract

The EWS/ETS fusion proteins associated with Ewings family tumors (EFTs) are thought to promote oncogenesis by acting as aberrant transcription factors. Uridine phosphorylase is a gene that is up-regulated by structurally distinct EWS/ETS fusions. Ectopic expression of uridine phosphorylase was able to support anchorage-independent cell growth, indicating that it plays an active role in the oncogenic process. Transcriptional up-regulation of uridine phosphorylase is shown to be mediated in a DNA binding-dependent manner, and reporter gene assays demonstrated that EWS/FLI1 and RAS mediate activation through a single activator protein 1/ETS site located in the uridine phosphorylase promoter. Chromatin immunoprecipitation assays reveal that EWS/FLI1 directly associates with the uridine phosphorylase promoter in vivo. Up-regulation of uridine phosphorylase by EWS/FLI1 sensitizes cells to growth inhibition by the pyrimidine analogue, 5'-deoxy-5'fluorouridine, both in tissue culture and in vivo model systems.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 3T3 Cells
  • Animals
  • DNA / metabolism
  • Floxuridine / pharmacology
  • Humans
  • Mice
  • Oncogene Proteins, Fusion / biosynthesis
  • Oncogene Proteins, Fusion / genetics
  • Oncogene Proteins, Fusion / physiology
  • Promoter Regions, Genetic
  • Protein Structure, Tertiary
  • Proto-Oncogene Protein c-fli-1
  • Proto-Oncogene Proteins / biosynthesis
  • Proto-Oncogene Proteins / genetics
  • Proto-Oncogene Proteins / physiology*
  • Proto-Oncogene Proteins c-ets
  • RNA-Binding Protein EWS / biosynthesis
  • RNA-Binding Protein EWS / genetics
  • RNA-Binding Protein EWS / physiology*
  • Recombinant Fusion Proteins / biosynthesis
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / physiology*
  • Transcription Factors / biosynthesis
  • Transcription Factors / genetics
  • Transcription Factors / physiology*
  • Transcription, Genetic
  • Transfection
  • Up-Regulation
  • Uridine Phosphorylase / biosynthesis
  • Uridine Phosphorylase / genetics
  • Uridine Phosphorylase / physiology*
  • ras Proteins / physiology

Substances

  • EWS-FLI fusion protein
  • Oncogene Proteins, Fusion
  • Proto-Oncogene Protein c-fli-1
  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-ets
  • RNA-Binding Protein EWS
  • Recombinant Fusion Proteins
  • Transcription Factors
  • Floxuridine
  • DNA
  • Uridine Phosphorylase
  • ras Proteins
  • doxifluridine