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Science (New York, N.Y.) Nov 2022Cereblon (CRBN) is a ubiquitin ligase (E3) substrate receptor protein co-opted by CRBN E3 ligase modulatory drug (CELMoD) agents that target therapeutically relevant...
Cereblon (CRBN) is a ubiquitin ligase (E3) substrate receptor protein co-opted by CRBN E3 ligase modulatory drug (CELMoD) agents that target therapeutically relevant proteins for degradation. Prior crystallographic studies defined the drug-binding site within CRBN's thalidomide-binding domain (TBD), but the allostery of drug-induced neosubstrate binding remains unclear. We performed cryo-electron microscopy analyses of the DNA damage-binding protein 1 (DDB1)-CRBN apo complex and compared these structures with DDB1-CRBN in the presence of CELMoD compounds alone and complexed with neosubstrates. Association of CELMoD compounds to the TBD is necessary and sufficient for triggering CRBN allosteric rearrangement from an open conformation to the canonical closed conformation. The neosubstrate Ikaros only stably associates with the closed CRBN conformation, illustrating the importance of allostery for CELMoD compound efficacy and informing structure-guided design strategies to improve therapeutic efficacy.
Topics: Adaptor Proteins, Signal Transducing; Cryoelectron Microscopy; Thalidomide; Ubiquitin-Protein Ligases; Protein Domains; Allosteric Regulation
PubMed: 36378961
DOI: 10.1126/science.add7574 -
Proceedings of the Japan Academy.... 2020Thalidomide, originally developed as a sedative drug, causes multiple defects due to severe teratogenicity, but it has been re-purposed for treating multiple myeloma,...
Thalidomide, originally developed as a sedative drug, causes multiple defects due to severe teratogenicity, but it has been re-purposed for treating multiple myeloma, and derivatives such as lenalidomide and pomalidomide have been developed for treating blood cancers. Although the molecular mechanisms of thalidomide and its derivatives remained poorly understood until recently, we identified cereblon (CRBN), a primary direct target of thalidomide, using ferrite glycidyl methacrylate (FG) beads. CRBN is a ligand-dependent substrate receptor of the E3 ubiquitin ligase complex cullin-RING ligase 4 (CRL4). When a ligand such as thalidomide binds to CRBN, it recognizes various 'neosubstrates' depending on the shape of the ligand. CRL4 binds many neosubstrates in the presence of various ligands. CRBN has been utilized in a novel protein knockdown technology named proteolysis targeting chimeras (PROTACs). Heterobifunctional molecules such as dBET1 are being developed to specifically degrade proteins of interest. Herein, we review recent advances in CRBN research.
Topics: Animals; Drug Repositioning; Humans; Molecular Targeted Therapy; Thalidomide
PubMed: 32522938
DOI: 10.2183/pjab.96.016 -
Annual Review of Pharmacology and... Jan 2024Thalidomide and its derivatives are powerful cancer therapeutics that are among the best-understood molecular glue degraders (MGDs). These drugs selectively reprogram... (Review)
Review
Thalidomide and its derivatives are powerful cancer therapeutics that are among the best-understood molecular glue degraders (MGDs). These drugs selectively reprogram the E3 ubiquitin ligase cereblon (CRBN) to commit target proteins for degradation by the ubiquitin-proteasome system. MGDs create novel recognition interfaces on the surface of the E3 ligase that engage in induced protein-protein interactions with neosubstrates. Molecular insight into their mechanism of action opens exciting opportunities to engage a plethora of targets through a specific recognition motif, the G-loop. Our analysis shows that current CRBN-based MGDs can in principle recognize over 2,500 proteins in the human proteome that contain a G-loop. We review recent advances in tuning the specificity between CRBN and its MGD-induced neosubstrates and deduce a set of simple rules that govern these interactions. We conclude that rational MGD design efforts will enable selective degradation of many more proteins, expanding this therapeutic modality to more disease areas.
Topics: Humans; Thalidomide; Proteolysis; Ubiquitin-Protein Ligases; Proteasome Endopeptidase Complex
PubMed: 37585660
DOI: 10.1146/annurev-pharmtox-022123-104147 -
Nature Chemistry Feb 2024Proteolysis-targeting chimeras (PROTACs) are molecules that induce proximity between target proteins and E3 ligases triggering target protein degradation. Pomalidomide,...
Proteolysis-targeting chimeras (PROTACs) are molecules that induce proximity between target proteins and E3 ligases triggering target protein degradation. Pomalidomide, a widely used E3 ligase recruiter in PROTACs, can independently degrade other proteins, including zinc-finger (ZF) proteins, with vital roles in health and disease. This off-target degradation hampers the therapeutic applicability of pomalidomide-based PROTACs, requiring development of PROTAC design rules that minimize off-target degradation. Here we developed a high-throughput platform that interrogates off-target degradation and found that reported pomalidomide-based PROTACs induce degradation of several ZF proteins. We generated a library of pomalidomide analogues to understand how functionalizing different positions of the phthalimide ring, hydrogen bonding, and steric and hydrophobic effects impact ZF protein degradation. Modifications of appropriate size on the C5 position reduced off-target ZF degradation, which we validated through target engagement and proteomics studies. By applying these design principles, we developed anaplastic lymphoma kinase oncoprotein-targeting PROTACs with enhanced potency and minimal off-target degradation.
Topics: Proteolysis; Ubiquitin-Protein Ligases; Proteins; Thalidomide
PubMed: 38110475
DOI: 10.1038/s41557-023-01379-8 -
Signal Transduction and Targeted Therapy Nov 2021Thalidomide induces γ-globin expression in erythroid progenitor cells, but its efficacy on patients with transfusion-dependent β-thalassemia (TDT) remains unclear. In... (Randomized Controlled Trial)
Randomized Controlled Trial
Thalidomide induces γ-globin expression in erythroid progenitor cells, but its efficacy on patients with transfusion-dependent β-thalassemia (TDT) remains unclear. In this phase 2, multi-center, randomized, double-blind clinical trial, we aimed to determine the safety and efficacy of thalidomide in TDT patients. A hundred patients of 14 years or older were randomly assigned to receive placebo or thalidomide for 12 weeks, followed by an extension phase of at least 36 weeks. The primary endpoint was the change of hemoglobin (Hb) level in the patients. The secondary endpoints included the red blood cell (RBC) units transfused and adverse effects. In the placebo-controlled period, Hb concentrations in patients treated with thalidomide achieved a median elevation of 14.0 (range, 2.5 to 37.5) g/L, whereas Hb in patients treated with placebo did not significantly change. Within the 12 weeks, the mean RBC transfusion volume for patients treated with thalidomide and placebo was 5.4 ± 5.0 U and 10.3 ± 6.4 U, respectively (P < 0.001). Adverse events of drowsiness, dizziness, fatigue, pyrexia, sore throat, and rash were more common with thalidomide than placebo. In the extension phase, treatment with thalidomide for 24 weeks resulted in a sustainable increase in Hb concentrations which reached 104.9 ± 19.0 g/L, without blood transfusion. Significant increase in Hb concentration and reduction in RBC transfusions were associated with non β0/β0 and HBS1L-MYB (rs9399137 C/T, C/C; rs4895441 A/G, G/G) genotypes. These results demonstrated that thalidomide is effective in patients with TDT.
Topics: Adolescent; Adult; Child; Double-Blind Method; Erythrocyte Transfusion; Female; Humans; Male; Thalidomide; beta-Thalassemia
PubMed: 34795208
DOI: 10.1038/s41392-021-00811-0 -
Angewandte Chemie (International Ed. in... Sep 2017The development of a new decarboxylative cross-coupling method that affords terminal and substituted alkynes from various carboxylic acids is described using both...
The development of a new decarboxylative cross-coupling method that affords terminal and substituted alkynes from various carboxylic acids is described using both nickel- and iron-based catalysts. The use of N-hydroxytetrachlorophthalimide (TCNHPI) esters is crucial to the success of the transformation, and the reaction is amenable to in situ carboxylic acid activation. Additionally, an inexpensive, commercially available alkyne source is employed in this formal homologation process that serves as a surrogate for other well-established alkyne syntheses. The reaction is operationally simple and broad in scope while providing succinct and scalable avenues to previously reported synthetic intermediates.
Topics: Alkynes; Decarboxylation; Esters; Molecular Structure; Nickel; Phthalimides; Thalidomide
PubMed: 28636185
DOI: 10.1002/anie.201705107 -
Journal of the American Academy of... Jul 2015Apremilast works intracellularly to regulate inflammatory mediators. (Randomized Controlled Trial)
Randomized Controlled Trial
Apremilast, an oral phosphodiesterase 4 (PDE4) inhibitor, in patients with moderate to severe plaque psoriasis: Results of a phase III, randomized, controlled trial (Efficacy and Safety Trial Evaluating the Effects of Apremilast in Psoriasis [ESTEEM] 1).
BACKGROUND
Apremilast works intracellularly to regulate inflammatory mediators.
OBJECTIVE
ESTEEM 1 evaluated efficacy/safety of apremilast at 30 mg twice a day for moderate to severe plaque psoriasis.
METHODS
This phase III, multicenter, double-blind, placebo-controlled study randomized adults (2:1) to apremilast or placebo. At week 16, the placebo group switched to apremilast through week 32, followed by a randomized treatment withdrawal phase to week 52. Binary end points were analyzed using χ(2) test; continuous end points used analysis of covariance.
RESULTS
In all, 844 patients were randomized (n = 282, placebo; n = 562, apremilast). At week 16, significantly more patients taking apremilast achieved 75% or greater reduction from baseline Psoriasis Area and Severity Index score (PASI-75) (33.1%) versus placebo (5.3%, P < .0001; primary end point). Most (61.0%) patients rerandomized to apremilast at week 32 achieved PASI-75 at week 52 versus 11.7% rerandomized to placebo. Of patients rerandomized to apremilast at week 32, mean percentage change from baseline PASI score was -88% to -81% (weeks 32-52). During the placebo-controlled period, 55.7% and 69.3% of patients randomized to placebo and apremilast, respectively, had 1 or more adverse events. Most adverse events were mild/moderate in severity. No new significant adverse events emerged with continued apremilast exposure versus the placebo-controlled period.
LIMITATIONS
Data were limited to 52 weeks and may not generalize to nonplaque psoriasis.
CONCLUSIONS
Apremilast was effective in moderate to severe plaque psoriasis.
Topics: Administration, Oral; Double-Blind Method; Female; Humans; Male; Middle Aged; Phosphodiesterase 4 Inhibitors; Psoriasis; Severity of Illness Index; Thalidomide
PubMed: 26089047
DOI: 10.1016/j.jaad.2015.03.049 -
Science (New York, N.Y.) Jun 2015The development of effective pharmacological inhibitors of multidomain scaffold proteins, notably transcription factors, is a particularly challenging problem. In part,...
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.
Topics: Adaptor Proteins, Signal Transducing; Animals; Azepines; Cell Cycle Proteins; Cell Line, Tumor; Crystallography, X-Ray; Disease Models, Animal; Drug Design; Leukemia, Promyelocytic, Acute; Ligands; Mice; Molecular Targeted Therapy; Nuclear Proteins; Peptide Hydrolases; Phthalimides; Protein Stability; Protein Structure, Tertiary; Proteolysis; Tacrolimus Binding Protein 1A; Thalidomide; Transcription Factors; Ubiquitin-Protein Ligases
PubMed: 25999370
DOI: 10.1126/science.aab1433 -
Blood Oct 2013This spotlight review focuses on the second-generation immunomodulatory drug pomalidomide, which was recently approved by the US Food and Drug Administration. This drug... (Review)
Review
This spotlight review focuses on the second-generation immunomodulatory drug pomalidomide, which was recently approved by the US Food and Drug Administration. This drug was approved for patients with multiple myeloma who have received at least 2 prior therapies, including lenalidomide and bortezomib, and have demonstrated disease progression on or within 60 days of completion of the last therapy. This review focuses on the clinical trial data that led to approval and provides advice for treating physicians who are now prescribing this drug for patients.
Topics: Clinical Trials as Topic; Humans; Immunologic Factors; Immunomodulation; Multiple Myeloma; Thalidomide
PubMed: 23974193
DOI: 10.1182/blood-2013-05-484782 -
Reumatismo Sep 2016Psoriatic arthritis (PsA) is a chronic inflammatory disease that possibly leads to structural damage and to a reduction of joint function and poor quality of life.... (Review)
Review
Psoriatic arthritis (PsA) is a chronic inflammatory disease that possibly leads to structural damage and to a reduction of joint function and poor quality of life. Treatment of PsA has changed since its introduction of anti- TNF drugs, which have shown to reduce the symptoms and signs of the disease and slow the radiographic progression. However, recently, the discovery of new pathogenic mechanisms have made possible the development of new molecules that target pro-inflammatory cytokines involved in skin, joint and entheseal inflammation. New drugs like ustekinumab, secukinumab and apremilast inhibit interleukin axis and intracellular pathways and showed their efficacy and safety in randomized clinical trials. These drugs have been recently approved for the treatment of PsA and included in the new EULAR and GRAPPA treatment recommendations. The aim of this paper is to briefly review the clinical trials that led to their approval for PsA.
Topics: Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antirheumatic Agents; Arthritis, Psoriatic; Clinical Trials as Topic; Dermatologic Agents; Humans; Randomized Controlled Trials as Topic; Thalidomide; Ustekinumab
PubMed: 27608793
DOI: 10.4081/reumatismo.2016.873