Impeded Nedd4-1-mediated Ras degradation underlies Ras-driven tumorigenesis

Cell Rep. 2014 May 8;7(3):871-82. doi: 10.1016/j.celrep.2014.03.045. Epub 2014 Apr 17.

Abstract

RAS genes are among the most frequently mutated proto-oncogenes in cancer. However, how Ras stability is regulated remains largely unknown. Here, we report a regulatory loop involving the E3 ligase Nedd4-1, Ras, and PTEN. We found that Ras signaling stimulates the expression of Nedd4-1, which in turn acts as an E3 ubiquitin ligase that regulates Ras levels. Importantly, Ras activation, either by oncogenic mutations or by epidermal growth factor (EGF) signaling, prevents Nedd4-1-mediated Ras ubiquitination. This leads to Ras-induced Nedd4-1 overexpression, and subsequent degradation of the tumor suppressor PTEN in both human cancer samples and cancer cells. Our study thus unravels the molecular mechanisms underlying the interplay of Ras, Nedd4-1, and PTEN and suggests a basis for the high prevalence of Ras-activating mutations and EGF hypersignaling in cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Carcinogenesis
  • Cell Line, Tumor
  • Endosomal Sorting Complexes Required for Transport / antagonists & inhibitors
  • Endosomal Sorting Complexes Required for Transport / genetics
  • Endosomal Sorting Complexes Required for Transport / metabolism*
  • Epidermal Growth Factor / metabolism
  • HEK293 Cells
  • HeLa Cells
  • Hep G2 Cells
  • Humans
  • Mice
  • Mice, Nude
  • NIH 3T3 Cells
  • Nedd4 Ubiquitin Protein Ligases
  • Neoplasms / metabolism
  • Neoplasms / pathology
  • PTEN Phosphohydrolase / metabolism
  • Protein Binding
  • Signal Transduction
  • Transplantation, Heterologous
  • Ubiquitin-Protein Ligases / antagonists & inhibitors
  • Ubiquitin-Protein Ligases / genetics
  • Ubiquitin-Protein Ligases / metabolism*
  • Ubiquitination
  • Up-Regulation
  • ras Proteins / metabolism*

Substances

  • Endosomal Sorting Complexes Required for Transport
  • Epidermal Growth Factor
  • Nedd4 Ubiquitin Protein Ligases
  • Nedd4 protein, human
  • Nedd4l protein, mouse
  • Ubiquitin-Protein Ligases
  • PTEN Phosphohydrolase
  • ras Proteins