Cereblon Modulators Target ZBTB16 and Its Oncogenic Fusion Partners for Degradation via Distinct Structural Degrons

ACS Chem Biol. 2020 Dec 18;15(12):3149-3158. doi: 10.1021/acschembio.0c00674. Epub 2020 Nov 18.

Abstract

There is a growing interest in using targeted protein degradation as a therapeutic modality in view of its potential to expand the druggable proteome. One avenue to using this modality is via molecular glue based Cereblon E3 Ligase Modulating Drug compounds. Here, we report the identification of the transcription factor ZBTB16 as a Cereblon neosubstrate. We also report two new Cereblon modulators, CC-3060 and CC-647, that promote ZBTB16 degradation. Unexpectedly, CC-3060 and CC-647 target ZBTB16 for degradation by primarily engaging distinct structural degrons on different zinc finger domains. The reciprocal fusion proteins, ZBTB16-RARα and RARα-ZBTB16, which cause a rare acute promyelocytic leukemia, contain these same structural degrons and can be targeted for proteasomal degradation with Cereblon modulator treatment. Thus, a targeted protein degradation approach via Cereblon modulators may represent a novel therapeutic strategy in acute promyelocytic leukemia where ZBTB16/RARA rearrangements are critical disease drivers.

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism*
  • Humans
  • Leukemia, Promyelocytic, Acute / metabolism
  • Oncogene Proteins, Fusion / metabolism*
  • Promyelocytic Leukemia Zinc Finger Protein / drug effects*
  • Proteolysis
  • Retinoic Acid Receptor alpha / metabolism
  • Substrate Specificity
  • Ubiquitin-Protein Ligases / metabolism*

Substances

  • Adaptor Proteins, Signal Transducing
  • CRBN protein, human
  • Oncogene Proteins, Fusion
  • Promyelocytic Leukemia Zinc Finger Protein
  • Retinoic Acid Receptor alpha
  • ZBTB16 protein, human
  • Ubiquitin-Protein Ligases