RÉSUMÉ
In this study, we describe the rapid identification of potent binders for the WD40 repeat domain (WDR) of DCAF1. This was achieved by two rounds of iterative focused screening of a small set of compounds selected on the basis of internal WDR domain knowledge followed by hit expansion. Subsequent structure-based design led to nanomolar potency binders with a clear exit vector enabling DCAF1-based bifunctional degrader exploration.
RÉSUMÉ
Polycomb Repressive Complex 2 (PRC2) plays an important role in transcriptional regulation during animal development and in cell differentiation, and alteration of PRC2 activity has been associated with cancer. On a molecular level, PRC2 catalyzes methylation of histone H3 lysine 27 (H3K27), resulting in mono-, di-, or trimethylated forms of H3K27, of which the trimethylated form H3K27me3 leads to transcriptional repression of polycomb target genes. Previously, we have shown that binding of the low-molecular-weight compound EED226 to the H3K27me3 binding pocket of the regulatory subunit EED can effectively inhibit PRC2 activity in cells and reduce tumor growth in mouse xenograft models. Here, we report the stepwise optimization of the tool compound EED226 toward the potent and selective EED inhibitor MAK683 (compound 22) and its subsequent preclinical characterization. Based on a balanced PK/PD profile, efficacy, and mitigated risk of forming reactive metabolites, MAK683 has been selected for clinical development.
Sujet(s)
Histone , Tumeurs , Animaux , Antienzymes , Histone/métabolisme , Humains , Méthylation , Souris , Tumeurs/traitement médicamenteux , Complexe répresseur Polycomb-2RÉSUMÉ
MALT1 plays a central role in immune cell activation by transducing NF-κB signaling, and its proteolytic activity represents a key node for therapeutic intervention. Two cycles of scaffold morphing of a high-throughput biochemical screening hit resulted in the discovery of MLT-231, which enabled the successful pharmacological validation of MALT1 allosteric inhibition in preclinical models of humoral immune responses and B-cell lymphomas. Herein, we report the structural activity relationships (SARs) and analysis of the physicochemical properties of a pyrazolopyrimidine-derived compound series. In human T-cells and B-cell lymphoma lines, MLT-231 potently and selectively inhibits the proteolytic activity of MALT1 in NF-κB-dependent assays. Both in vitro and in vivo profiling of MLT-231 support further optimization of this in vivo tool compound toward preclinical characterization.
Sujet(s)
Inhibiteurs des caspases/usage thérapeutique , Protéine-1 de translocation de lymphome du tissu lymphoïde associé aux muqueuses/antagonistes et inhibiteurs , Tumeurs/traitement médicamenteux , Urée/analogues et dérivés , Urée/usage thérapeutique , Animaux , Antinéoplasiques/synthèse chimique , Antinéoplasiques/pharmacologie , Antinéoplasiques/usage thérapeutique , Inhibiteurs des caspases/synthèse chimique , Inhibiteurs des caspases/pharmacologie , Découverte de médicament , Femelle , Humains , Immunité humorale/effets des médicaments et des substances chimiques , Mâle , Souris de lignée BALB C , Structure moléculaire , Pyrazoles/synthèse chimique , Pyrazoles/pharmacologie , Pyrazoles/usage thérapeutique , Pyrimidines/synthèse chimique , Pyrimidines/pharmacologie , Pyrimidines/usage thérapeutique , Rat Sprague-Dawley , Relation structure-activité , Lymphocytes T/effets des médicaments et des substances chimiques , Urée/pharmacologie , Tests d'activité antitumorale sur modèle de xénogreffeRÉSUMÉ
The paracaspase MALT1 has gained increasing interest as a target for the treatment of subsets of lymphomas as well as autoimmune diseases, and there is a need for suitable compounds to explore the therapeutic potential of this target. Here, we report the optimization of the in vivo potency of pyrazolopyrimidines, a class of highly selective allosteric MALT1 inhibitors. High doses of the initial lead compound led to tumor stasis in an activated B-cell-like (ABC) diffuse large B-cell lymphoma (DLBCL) xenograft model, but this compound suffered from a short in vivo half-life and suboptimal potency in whole blood. Guided by metabolism studies, we identified compounds with reduced metabolic clearance and increased in vivo half-life. In the second optimization step, masking one of the hydrogen-bond donors of the central urea moiety through an intramolecular interaction led to improved potency in whole blood. This was associated with improved in vivo potency in a mechanistic model of B cell activation. The optimized compound led to tumor regression in a CARD11 mutant ABC-DLBCL lymphoma xenograft model.
Sujet(s)
Sang/métabolisme , Inhibiteurs des caspases/usage thérapeutique , Protéine-1 de translocation de lymphome du tissu lymphoïde associé aux muqueuses/antagonistes et inhibiteurs , Pyrazoles/usage thérapeutique , Pyrimidines/usage thérapeutique , Urée/usage thérapeutique , Animaux , Antinéoplasiques/synthèse chimique , Antinéoplasiques/métabolisme , Antinéoplasiques/pharmacocinétique , Antinéoplasiques/usage thérapeutique , Inhibiteurs des caspases/synthèse chimique , Inhibiteurs des caspases/métabolisme , Inhibiteurs des caspases/pharmacocinétique , Lignée cellulaire tumorale , Femelle , Période , Humains , Souris de lignée BALB C , Souris SCID , Microsomes du foie/métabolisme , Tumeurs/traitement médicamenteux , Pyrazoles/synthèse chimique , Pyrazoles/métabolisme , Pyrazoles/pharmacocinétique , Pyrimidines/synthèse chimique , Pyrimidines/métabolisme , Pyrimidines/pharmacocinétique , Rat Sprague-Dawley , Ovis , Urée/synthèse chimique , Urée/métabolisme , Urée/pharmacocinétique , Tests d'activité antitumorale sur modèle de xénogreffeRÉSUMÉ
Starting from a weak screening hit, potent and selective inhibitors of the MALT1 protease function were elaborated. Advanced compounds displayed high potency in biochemical and cellular assays. Compounds showed activity in a mechanistic Jurkat T cell activation assay as well as in the B-cell lymphoma line OCI-Ly3, which suggests potential use of MALT1 inhibitors in the treatment of autoimmune diseases as well as B-cell lymphomas with a dysregulated NF-κB pathway. Initially, rat pharmacokinetic properties of this compound series were dominated by very high clearance which could be linked to amide cleavage. Using a rat hepatocyte assay a good in vitro-in vivo correlation could be established which led to the identification of compounds with improved PK properties.
Sujet(s)
Antinéoplasiques/pharmacologie , Protéine-1 de translocation de lymphome du tissu lymphoïde associé aux muqueuses/antagonistes et inhibiteurs , Pipéridines/pharmacologie , Animaux , Antinéoplasiques/synthèse chimique , Antinéoplasiques/composition chimique , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Relation dose-effet des médicaments , Hépatocytes/effets des médicaments et des substances chimiques , Humains , Cellules Jurkat , Microsomes/effets des médicaments et des substances chimiques , Structure moléculaire , Protéine-1 de translocation de lymphome du tissu lymphoïde associé aux muqueuses/métabolisme , Pipéridines/synthèse chimique , Pipéridines/composition chimique , Protéolyse/effets des médicaments et des substances chimiques , Rats , Relation structure-activitéRÉSUMÉ
Mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) is essential for immune responses triggered by antigen receptors but the contribution of its paracaspase activity is not fully understood. Here, we studied how MALT1 proteolytic function regulates T-cell activation and fate after engagement of the T-cell receptor pathway. We show that MLT-827, a potent and selective MALT1 paracaspase inhibitor, does not prevent the initial phase of T-cell activation, in contrast to the pan-protein kinase C inhibitor AEB071. However, MLT-827 strongly impacted cell expansion after activation. We demonstrate this is the consequence of profound inhibition of IL-2 production as well as reduced expression of the IL-2 receptor alpha subunit (CD25), resulting from defective canonical NF-κB activation and accelerated mRNA turnover mechanisms. Accordingly, MLT-827 revealed a unique transcriptional fingerprint of MALT1 protease activity, providing evidence for broad control of T-cell signaling pathways. Altogether, this first report with a potent and selective inhibitor elucidates how MALT1 paracaspase activity integrates several T-cell activation pathways and indirectly controls gamma-chain receptor dependent survival, to impact on T-cell expansion.
Sujet(s)
Protéine-1 de translocation de lymphome du tissu lymphoïde associé aux muqueuses/métabolisme , Facteur de transcription NF-kappa B/métabolisme , Lymphocytes T/immunologie , Prolifération cellulaire , Survie cellulaire , Cellules cultivées , Régulation de l'expression des gènes , Humains , Immunomodulation , Interleukine-2/métabolisme , Sous-unité alpha du récepteur à l'interleukine-2/métabolisme , Activation des lymphocytes , Protéolyse , Récepteurs aux antigènes des cellules T/métabolisme , Transduction du signalRÉSUMÉ
As a result of our efforts to discover novel p53:MDM2 protein-protein interaction inhibitors useful for treating cancer, the potent and selective MDM2 inhibitor NVP-CGM097 (1) with an excellent in vivo profile was selected as a clinical candidate and is currently in phase 1 clinical development. This article provides an overview of the discovery of this new clinical p53:MDM2 inhibitor. The following aspects are addressed: mechanism of action, scientific rationale, binding mode, medicinal chemistry, pharmacokinetic and pharmacodynamic properties, and in vivo pharmacology/toxicology in preclinical species.
Sujet(s)
Antinéoplasiques/synthèse chimique , Antinéoplasiques/pharmacologie , Isoquinoléines/synthèse chimique , Isoquinoléines/pharmacologie , Pipérazines/synthèse chimique , Pipérazines/pharmacologie , Protéines proto-oncogènes c-mdm2/antagonistes et inhibiteurs , Protéine p53 suppresseur de tumeur/génétique , Animaux , Antinéoplasiques/pharmacocinétique , Lignée cellulaire tumorale , Essais cliniques de phase I comme sujet , Découverte de médicament , Humains , Isoquinoléines/pharmacocinétique , Pipérazines/pharmacocinétique , Rats , Relation structure-activité , Tests d'activité antitumorale sur modèle de xénogreffeRÉSUMÉ
Janus kinase (JAK) inhibitors are being developed for the treatment of rheumatoid arthritis, psoriasis, myeloproliferative neoplasms, and leukemias. Most of these drugs target the ATP-binding pocket and stabilize the active conformation of the JAK kinases. This type I binding mode can lead to an increase in JAK activation loop phosphorylation, despite blockade of kinase function. Here we report that stabilizing the inactive state via type II inhibition acts in the opposite manner, leading to a loss of activation loop phosphorylation. We used X-ray crystallography to corroborate the binding mode and report for the first time the crystal structure of the JAK2 kinase domain in an inactive conformation. Importantly, JAK inhibitor-induced activation loop phosphorylation requires receptor interaction, as well as intact kinase and pseudokinase domains. Hence, depending on the respective conformation stabilized by a JAK inhibitor, hyperphosphorylation of the activation loop may or may not be elicited.
Sujet(s)
Janus kinases/antagonistes et inhibiteurs , Janus kinases/composition chimique , Inhibiteurs de protéines kinases/pharmacologie , Animaux , Sites de fixation , Lignée cellulaire tumorale , Humains , Kinase Janus-2/antagonistes et inhibiteurs , Kinase Janus-2/composition chimique , Souris , Phosphorylation/effets des médicaments et des substances chimiques , Liaison aux protéines , Structure tertiaire des protéines , Facteur de transcription STAT-5/métabolismeRÉSUMÉ
The recent discovery of an acquired activating point mutation in JAK2, substituting valine at amino acid position 617 for phenylalanine, has greatly improved our understanding of the molecular mechanism underlying chronic myeloproliferative neoplasms. Strikingly, the JAK2(V617F) mutation is found in nearly all patients suffering from polycythemia vera and in roughly every second patient suffering from essential thrombocythemia and primary myelofibrosis. Thus, JAK2 represents a promising target for the treatment of myeloproliferative neoplasms and considerable efforts are ongoing to discover and develop inhibitors of the kinase. Here, we report potent inhibition of JAK2(V617F) and JAK2 wild-type enzymes by a novel substituted quinoxaline, NVP-BSK805, which acts in an ATP-competitive manner. Within the JAK family, NVP-BSK805 displays more than 20-fold selectivity towards JAK2 in vitro, as well as excellent selectivity in broader kinase profiling. The compound blunts constitutive STAT5 phosphorylation in JAK2(V617F)-bearing cells, with concomitant suppression of cell proliferation and induction of apoptosis. In vivo, NVP-BSK805 exhibited good oral bioavailability and a long half-life. The inhibitor was efficacious in suppressing leukemic cell spreading and splenomegaly in a Ba/F3 JAK2(V617F) cell-driven mouse mechanistic model. Furthermore, NVP-BSK805 potently suppressed recombinant human erythropoietin-induced polycythemia and extramedullary erythropoiesis in mice and rats.
Sujet(s)
Prolifération cellulaire/effets des médicaments et des substances chimiques , Kinase Janus-2/antagonistes et inhibiteurs , Polyglobulie/prévention et contrôle , Quinoxalines/pharmacologie , Adénosine triphosphate/pharmacologie , Animaux , Apoptose/effets des médicaments et des substances chimiques , Lignée cellulaire , Lignée cellulaire tumorale , Érythropoïèse/effets des médicaments et des substances chimiques , Humains , Kinase Janus-2/composition chimique , Kinase Janus-2/génétique , Cellules K562 , Souris , Souris de lignée BALB C , Souris SCID , Modèles moléculaires , Structure moléculaire , Mutation , Phosphorylation/effets des médicaments et des substances chimiques , Polyglobulie/métabolisme , Polyglobulie/anatomopathologie , Structure tertiaire des protéines , Quinoxalines/composition chimique , Rats , Facteur de transcription STAT-5/métabolisme , Splénomégalie/métabolisme , Splénomégalie/anatomopathologie , Splénomégalie/prévention et contrôleRÉSUMÉ
We have designed and synthesized a novel series of 2,8-diaryl-quinoxalines as Janus kinase 2 inhibitors. Many of the inhibitors show low nanomolar activity against JAK2 and potently suppress proliferation of SET-2 cells in vitro. In addition, compounds from this series have favorable rat pharmacokinetic properties suitable for in vivo efficacy evaluation.
Sujet(s)
Kinase Janus-2/antagonistes et inhibiteurs , Inhibiteurs de protéines kinases/composition chimique , Inhibiteurs de protéines kinases/pharmacologie , Quinoxalines/composition chimique , Quinoxalines/pharmacologie , Administration par voie orale , Animaux , Lignée cellulaire , Découverte de médicament , Évaluation préclinique de médicament , Modèles moléculaires , Inhibiteurs de protéines kinases/pharmacocinétique , Quinoxalines/pharmacocinétique , Rats , Relation structure-activitéRÉSUMÉ
A series of novel benzoxazole derivatives has been designed and shown to exhibit attractive JAK2 inhibitory profiles in biochemical and cellular assays, capable of delivering compounds with favorable PK properties in rats. Synthesis and structure-activity relationship data are also provided.
Sujet(s)
Benzoxazoles/composition chimique , Kinase Janus-2/antagonistes et inhibiteurs , Inhibiteurs de protéines kinases/composition chimique , Administration par voie orale , Animaux , Benzoxazoles/synthèse chimique , Benzoxazoles/pharmacocinétique , Kinase Janus-2/métabolisme , Inhibiteurs de protéines kinases/synthèse chimique , Inhibiteurs de protéines kinases/pharmacocinétique , Rats , Relation structure-activitéRÉSUMÉ
JAK2 is a target of high interest in chronic myeloproliferative disorders drug research. Starting from a screening hit, two new JAK2 inhibitor chemotypes were designed by scaffold morphing. The prototype compounds of these new series showed nanomolar inhibition of the kinase.
Sujet(s)
Kinase Janus-2/antagonistes et inhibiteurs , Inhibiteurs de protéines kinases/synthèse chimique , Inhibiteurs de protéines kinases/pharmacologie , Conception de médicament , Modèles moléculairesRÉSUMÉ
The interesting biological properties of the hamigerans wherein hamigeran B is a potent antiviral agent with low cytotoxicity to host cells make these deceptively simple looking structures challenging synthetic targets. A strategy to hamigeran B evolved wherein the three contiguous stereocenters are established ultimately from a Pd catalyzed asymmetric allylic alkylation (AAA). The latter involves an asymmetric allylation of a non-stabilized ketone enolate in 77 % yield and 93 % ee. By using this process, (S)-5-allyl-2-isopropyl-5-methyl-1-trifluoromethanesulfonyloxycyclopentene becomes available in four steps from 2-methylcyclopentanone. Introduction of the aryl unit by cross-coupling proceeded intermolecularly but failed intramolecularly. On the other hand, reductive removal of the triflate permitted a Heck reaction to effect intramolecular introduction of the aryl ring. The unusual conformational properties of this molecular architecture are revealed by the regioselectivity of the beta-hydrogen elimination in the Heck reaction and the diastereoselectivity of the reduction establishing the stereochemistry of the carbon bearing the isopropyl group. The successful route consists of 15 steps from 2-methylcyclopentanone and dimethylorcinol illustrating the efficiency of the route based upon the Pd AAA.
Sujet(s)
Naphtoquinones/synthèse chimique , Hydrogénation , Cinétique , Modèles chimiques , Conformation moléculaire , Naphtoquinones/composition chimique , StéréoisomérieRÉSUMÉ
A protocol for the asymmetric allylic alkylation of a five-membered ring ketone derivative that employs the lithium enolate in the presence of lithium alkoxides gave high yields and enantioselectivities. This product serves as a versatile intermediate as demonstrated in a convergent total synthesis of the antiviral agent hamigeran B. The sequence involves two unusual observations. In the intramolecular Heck reaction which establishes the complete ring sytem, the beta-H elimination step occurs both endocyclic (as expected) and exocyclic, the latter most surprising since it creates an exocylic tetrasubstituted double bond. In the catalytic hydrogenation, use of Pd/C gives complete selectivity for net delivery of hydrogen to the most hindered face of the substrate, whereas use of Ir black gives complete selectivity for delivery of hydrogen to the least hindered face. Such unusual behavior speaks to the unusual chemical properties associated with hamigeran B which may be relevant to its biological activity.