Novel small molecules potentiate premature termination codon readthrough by aminoglycosides

Alireza Baradaran-Heravi1, Aruna D Balgi1, Carla Zimmerman1

  • 1Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.

Insights

Scientists found a compound that significantly boosts the effectiveness of existing drugs in correcting genetic defects caused by nonsense mutations, offering new hope for treating genetic diseases.

Area of Science:

  • Genetics
  • Pharmacology
  • Molecular Biology

Background:

  • Nonsense mutations, causing premature stop codons, are responsible for 11% of genetic diseases.
  • Aminoglycosides can promote readthrough of these codons but with limited efficiency.

Purpose of the Study:

  • To identify compounds that enhance aminoglycoside-induced nonsense mutation readthrough.
  • To develop a potent therapeutic strategy for genetic diseases stemming from nonsense mutations.

Main Methods:

  • High-throughput screening in yeast to identify readthrough-potentiating compounds.
  • Chemical optimization of lead compounds, resulting in phthalimide derivative CDX5-1.
  • Testing CDX5-1 in combination with aminoglycoside G418 in human cancer cell lines and patient-derived cells.

Main Results:

  • CDX5-1 significantly potentiated G418-induced readthrough (up to 180-fold) in TP53 nonsense mutant cancer cells.
  • The combination therapy demonstrated efficacy across multiple TP53 nonsense alleles.
  • Readthrough was also successfully enhanced in patient cells with nonsense mutations in CLN2, SMARCAL1, and DMD genes.

Conclusions:

  • Phthalimide derivative CDX5-1, in combination with aminoglycosides, is a potent enhancer of nonsense mutation readthrough.
  • This combination therapy shows promise for treating a wide range of genetic disorders caused by various nonsense mutations.
  • The findings open avenues for developing novel treatments for genetic diseases previously considered intractable.

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