2015/05/21 by Georg E. Winter, Dennis L. Buckley, Joshiawa Paulk +5 · 45 citations
Biochemistry, Genetics and Molecular Biology · Medicine · #Protein Degradation and Inhibitors #Ubiquitin and proteasome pathways #Multiple Myeloma Research and Treatments
paper · doi:10.1126/science.aab1433
The development of effective pharmacological inhibitors of multidomain scaffold proteins, notably transcription factors, is a particularly challenging problem. In part, this is because many small-molecule antagonists disrupt the activity of only one domain in the target protein. We devised a chemical strategy that promotes ligand-dependent target protein degradation using as an example the transcriptional coactivator BRD4, a protein critical for cancer cell growth and survival. We appended a competitive antagonist of BET bromodomains to a phthalimide moiety to hijack the cereblon E3 ubiquitin ligase complex. The resultant compound, dBET1, induced highly selective cereblon-dependent BET protein degradation in vitro and in vivo and delayed leukemia progression in mice. A second series of probes resulted in selective degradation of the cytosolic protein FKBP12. This chemical strategy for controlling target protein stability may have implications for therapeutically targeting previously intractable proteins.