Solid-Phase Synthesis of Cereblon-Recruiting Selective Histone Deacetylase 6 Degraders (HDAC6 PROTACs) with Antileukemic Activity

J Med Chem. 2022 Dec 22;65(24):16860-16878. doi: 10.1021/acs.jmedchem.2c01659. Epub 2022 Dec 6.

Abstract

In this work, we utilized the proteolysis targeting chimera (PROTAC) technology to achieve the chemical knock-down of histone deacetylase 6 (HDAC6). Two series of cereblon-recruiting PROTACs were synthesized via a solid-phase parallel synthesis approach, which allowed the rapid preparation of two HDAC6 degrader mini libraries. The PROTACs were either based on an unselective vorinostat-like HDAC ligand or derived from a selective HDAC6 inhibitor. Notably, both PROTAC series demonstrated selective degradation of HDAC6 in leukemia cell lines. The best degraders from each series (denoted A6 and B4) were capable of degrading HDAC6 via ternary complex formation and the ubiquitin-proteasome pathway, with DC50 values of 3.5 and 19.4 nM, respectively. PROTAC A6 demonstrated promising antiproliferative activity via inducing apoptosis in myeloid leukemia cell lines. These findings highlight the potential of this series of degraders as effective pharmacological tools for the targeted degradation of HDAC6.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents* / pharmacology
  • Cell Proliferation
  • Histone Deacetylase 6
  • Proteolysis
  • Proteolysis Targeting Chimera
  • Solid-Phase Synthesis Techniques
  • Ubiquitin-Protein Ligases / metabolism

Substances

  • Histone Deacetylase 6
  • Antineoplastic Agents
  • Proteolysis Targeting Chimera
  • Ubiquitin-Protein Ligases