Crystal structures of NUDT15 variants enabled by a potent inhibitor reveal the structural basis for thiopurine sensitivity

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Abstract

The enzyme NUDT15 efficiently hydrolyses the active metabolites of thiopurine drugs, which are routinely used for treating cancer and inflammatory diseases. Loss-of-function variants in NUDT15 are strongly associated with thiopurine intolerance, such as leukopenia, and pre-emptive NUDT15 genotyping has been clinically implemented to personalize thiopurine dosing. However, understanding the molecular consequences of these variants has been difficult, as no structural information was available for NUDT15 proteins encoded by clinically actionable pharmacogenetic variants due to their inherent instability. Recently, the small molecule NUDT15 inhibitor TH1760 has been shown to sensitize cells to thiopurines, through enhanced accumulation of 6-thio-guanine in DNA. Building upon this, we herein report the development of the potent and specific NUDT15 inhibitor, TH7755. TH7755 demonstrates a greatly improved cellular target engagement and 6-thioguanine potentiation compared to TH1760, while showing no cytotoxicity on its own. This potent inhibitor also stabilized NUDT15, enabling analysis by X-ray crystallography. We have determined high-resolution structures of the clinically relevant NUDT15 variants Arg139Cys, Arg139His, Val18Ile and V18_V19insGlyVal. These structures provide clear insights into the structural basis for the thiopurine intolerance phenotype observed in patients carrying these pharmacogenetic variants. These findings will aid in predicting the effects of new NUDT15 sequence variations yet to be discovered in the clinic.

Detaljer

Författare
  • Daniel Rehling
  • Si Min Zhang
  • Ann-Sofie Jemth
  • Tobias Koolmeister
  • Adam Throup
  • Olov Wallner
  • Emma Scaletti
  • Takaya Moriyama
  • Rina Nishii
  • Jonathan Davies
  • Matthieu Desroses
  • Sean G Rudd
  • Martin Scobie
  • Evert Homan
  • Ulrika Warpman Berglund
  • Jun J Yang
  • Thomas Helleday
  • Pål Stenmark
Enheter & grupper
Externa organisationer
  • St Jude Children´s Research Hospital, Memphis
  • Sheffield Hallam University
  • Stockholms universitet
  • Karolinska Institute
  • Lund University
Forskningsområden

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Biokemi och molekylärbiologi
  • Farmakologi och toxikologi
Originalspråkengelska
Artikelnummer100568
TidskriftThe Journal of biological chemistry
Volym296
Tidigt onlinedatum2021 mar 19
StatusPublished - 2021
PublikationskategoriForskning
Peer review utfördJa