Design of Murine Double Minute 2 Proteolysis Targeting Chimera Degraders with a Built-In Tumor-Targeting Ability

J Med Chem. 2024 Nov 14;67(21):18865-18882. doi: 10.1021/acs.jmedchem.4c01228. Epub 2024 Oct 22.

Abstract

Proteolysis targeting chimeras (PROTACs) are heterobifunctional molecules to induce the proteasomal degradation of target proteins. Currently, there are no tumor-targeting PROTACs for modulating oncogenic murine double minute 2 (MDM2). AS1411 is a tumor-targeting aptamer that specifically recognizes nucleolin (NCL) overexpressed on the surface of tumor cells. We recently repurposed AS1411 as an MDM2 recruiter since it could form an NCL-bridged ternary complex with MDM2. In this study, we design a PROTAC molecule AS1411-VH032 via conjugating AS1411 with a recruiter of von Hippel-Lindau (VHL) ligase VH032. AS1411-VH032 facilitates tumor-selective degradation of MDM2, leading to tumor shrinkage with no detectable toxicity. Besides being a molecular target, MDM2 also serves as an E3 ligase harnessed by PROTACs. Thus, we developed an AS1411-based homo-PROTAC homoAS1411, which induces tumor-specific suicide degradation of MDM2 and prevents tumor progression without causing side effects. Both AS1411-VH032 and homoAS1411 are promising MDM2 degraders with built-in tumor-targeting ability, which balances the antitumor efficacy with a favorable safety profile.

MeSH terms

  • Animals
  • Antineoplastic Agents* / chemical synthesis
  • Antineoplastic Agents* / chemistry
  • Antineoplastic Agents* / pharmacology
  • Antineoplastic Agents* / therapeutic use
  • Aptamers, Nucleotide / chemistry
  • Aptamers, Nucleotide / pharmacology
  • Cell Line, Tumor
  • Drug Design
  • Female
  • Humans
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • Nucleolin
  • Proteolysis Targeting Chimera
  • Proteolysis* / drug effects
  • Proto-Oncogene Proteins c-mdm2* / antagonists & inhibitors
  • Proto-Oncogene Proteins c-mdm2* / metabolism
  • RNA-Binding Proteins / metabolism
  • Von Hippel-Lindau Tumor Suppressor Protein / metabolism

Substances

  • Proto-Oncogene Proteins c-mdm2
  • Antineoplastic Agents
  • Aptamers, Nucleotide
  • Von Hippel-Lindau Tumor Suppressor Protein
  • Nucleolin
  • RNA-Binding Proteins
  • Proteolysis Targeting Chimera