USP37 directly deubiquitinates and stabilizes c-Myc in lung cancer

Oncogene. 2015 Jul 23;34(30):3957-67. doi: 10.1038/onc.2014.327. Epub 2014 Oct 6.

Abstract

The oncoprotein c-Myc is frequently overexpressed in many cancers and is essential for cancer cell proliferation. Ubiquitin-proteasome-dependent degradation is one of the main ways in which cells control c-Myc abundance at a post-translational level. However, the underlying mechanism by which c-Myc is directly deubiquitinated is not fully understood. In this study, by screening ubiquitin-specific proteases (USPs) that may regulate c-Myc stability, we identified USP37 as a novel deubiquitinating enzyme (DUB) that stabilizes c-Myc via direct binding. The overexpression of USP37 markedly increases c-Myc abundance by blocking its degradation, whereas the depletion of USP37 promotes c-Myc degradation and reduces c-Myc levels. Further studies indicate that USP37 directly interacts with c-Myc and deubiquitinates c-Myc in a DUB activity-dependent manner. Functionally, USP37 regulates cell proliferation and the Warburg effect by regulating c-Myc levels. Clinically, USP37 is significantly upregulated in human lung cancer tissues, where its expression is positively correlated with c-Myc protein expression. Thus, our findings uncover a previously unrecognized role for USP37 in the regulation of c-Myc stability in lung cancer and suggest that USP37 might be a potential therapeutic target for the treatment of lung cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / enzymology*
  • Cell Proliferation
  • Endopeptidases / physiology*
  • Glycolysis
  • HEK293 Cells
  • HeLa Cells
  • Humans
  • Lung Neoplasms / enzymology*
  • Protein Stability
  • Proto-Oncogene Proteins c-myc / metabolism*
  • Ubiquitination*

Substances

  • MYC protein, human
  • Proto-Oncogene Proteins c-myc
  • Endopeptidases
  • USP37 protein, human