eLife (Oct 2021)

USP28 deletion and small-molecule inhibition destabilizes c-MYC and elicits regression of squamous cell lung carcinoma

  • E Josue Ruiz,
  • Adan Pinto-Fernandez,
  • Andrew P Turnbull,
  • Linxiang Lan,
  • Thomas M Charlton,
  • Hannah C Scott,
  • Andreas Damianou,
  • George Vere,
  • Eva M Riising,
  • Clive Da Costa,
  • Wojciech W Krajewski,
  • David Guerin,
  • Jeffrey D Kearns,
  • Stephanos Ioannidis,
  • Marie Katz,
  • Crystal McKinnon,
  • Jonathan O'Connell,
  • Natalia Moncaut,
  • Ian Rosewell,
  • Emma Nye,
  • Neil Jones,
  • Claire Heride,
  • Malte Gersch,
  • Min Wu,
  • Christopher J Dinsmore,
  • Tim R Hammonds,
  • Sunkyu Kim,
  • David Komander,
  • Sylvie Urbe,
  • Michael J Clague,
  • Benedikt M Kessler,
  • Axel Behrens

DOI
https://doi.org/10.7554/eLife.71596
Journal volume & issue
Vol. 10

Abstract

Read online

Lung squamous cell carcinoma (LSCC) is a considerable global health burden, with an incidence of over 600,000 cases per year. Treatment options are limited, and patient’s 5-year survival rate is less than 5%. The ubiquitin-specific protease 28 (USP28) has been implicated in tumourigenesis through its stabilization of the oncoproteins c-MYC, c-JUN, and Δp63. Here, we show that genetic inactivation of Usp28-induced regression of established murine LSCC lung tumours. We developed a small molecule that inhibits USP28 activity in the low nanomole range. While displaying cross-reactivity against the closest homologue USP25, this inhibitor showed a high degree of selectivity over other deubiquitinases. USP28 inhibitor treatment resulted in a dramatic decrease in c-MYC, c-JUN, and Δp63 proteins levels and consequently induced substantial regression of autochthonous murine LSCC tumours and human LSCC xenografts, thereby phenocopying the effect observed by genetic deletion. Thus, USP28 may represent a promising therapeutic target for the treatment of squamous cell lung carcinoma.

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