Investigating the NRAS 5' UTR as a target for small molecules

  • Cell Chem Biol. 2023 Jun 15;30(6):643-657.e8. doi: 10.1016/j.chembiol.2023.05.004.
Sumirtha Balaratnam  1 ,  Zachary R Torrey  1 ,  David R Calabrese  1 ,  Michael T Banco  2 ,  Kamyar Yazdani  1 ,  Xiao Liang  1 ,  Christopher R Fullenkamp  1 ,  Srinath Seshadri  1 ,  Ronald J Holewinski  3 ,  Thorkell Andresson  3 ,  Adrian R Ferré-D'Amaré  2 ,  Danny Incarnato  4 ,  John S Schneekloth Jr  5
Affiliations
  • 1. Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA.
  • 2. Biochemistry and Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, MD 20892, USA.
  • 3. Protein Characterization Laboratory, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc, Frederick, MD 21702, USA.
  • 4. Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Groningen, the Netherlands.
  • 5. Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA. Electronic address: [email protected].
PMID: 37257453 DOI: 10.1016/j.chembiol.2023.05.004
Abstract

Neuroblastoma Ras (NRAS) is an oncogene that is deregulated and highly mutated in cancers including melanomas and acute myeloid leukemias. The 5' untranslated region (UTR) (5' UTR) of the NRAS mRNA contains a G-quadruplex (G4) that regulates translation. Here we report a novel class of small molecule that binds to the G4 structure located in the 5' UTR of the NRAS mRNA. We used a small molecule microarray screen to identify molecules that selectively bind to the NRAS-G4 with submicromolar affinity. One compound inhibits the translation of NRAS in vitro but showed only moderate effects on the NRAS levels in cellulo. Rapid Amplification of cDNA Ends and RT-PCR analysis revealed that the predominant NRAS transcript does not possess the G4 structure. Thus, although NRAS transcripts lack a G4 in many cell lines the concept of targeting folded regions within 5' UTRs to control translation remains a highly attractive strategy.

Keywords
NRAS; RAS targeting; RNA G-quadruplex; RNA targeting; SMM screening strategy; small molecules.
Products