RESUMO
CC-122 is a next-generation cereblon E3 ligase-modulating agent that has demonstrated promising clinical efficacy in patients with relapsed or refractory diffuse large B-cell lymphoma (R/R DLBCL). Mechanistically, CC-122 induces the degradation of IKZF1/3, leading to T-cell activation and robust cell-autonomous killing in DLBCL. We report a genome-wide CRISPR/Cas9 screening for CC-122 in a DLBCL cell line SU-DHL-4 with follow-up mechanistic characterization in 6 DLBCL cell lines to identify genes regulating the response to CC-122. Top-ranked CC-122 resistance genes encode, not only well-defined members or regulators of the CUL4/DDB1/RBX1/CRBN E3 ubiquitin ligase complex, but also key components of signaling and transcriptional networks that have not been shown to modulate the response to cereblon modulators. Ablation of CYLD, NFKBIA, TRAF2, or TRAF3 induces hyperactivation of the canonical and/or noncanonical NF-κB pathways and subsequently diminishes CC-122-induced apoptosis in 5 of 6 DLBCL cell lines. Depletion of KCTD5, the substrate adaptor of the CUL3/RBX1/KCTD5 ubiquitin ligase complex, promotes the stabilization of its cognate substrate, GNG5, resulting in CC-122 resistance in HT, SU-DHL-4, and WSU-DLCL2. Furthermore, knockout of AMBRA1 renders resistance to CC-122 in SU-DHL-4 and U-2932, whereas knockout of RFX7 leads to resistance specifically in SU-DHL-4. The ubiquitous and cell line-specific mechanisms of CC-122 resistance in DLBCL cell lines revealed in this work pinpoint genetic alternations that are potentially associated with clinical resistance in patients and facilitate the development of biomarker strategies for patient stratification, which may improve clinical outcomes of patients with R/R DLBCL.
Assuntos
Linfoma Difuso de Grandes Células B , Piperidonas , Proteínas Adaptadoras de Transdução de Sinal , Linhagem Celular Tumoral , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Canais de Potássio , Quinazolinonas , Ubiquitina-Proteína LigasesRESUMO
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.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Proteína com Dedos de Zinco da Leucemia Promielocítica/efeitos dos fármacos , Ubiquitina-Proteína Ligases/metabolismo , Humanos , Leucemia Promielocítica Aguda/metabolismo , Proteólise , Receptor alfa de Ácido Retinoico/metabolismo , Especificidade por SubstratoRESUMO
PURPOSE: To discover the best orientation method for perianesthesia nurses. DESIGN: Pilot study comparing two approaches to orientation. METHODS: Nurses in one group were each assigned to a single preceptor, whom they followed regardless of which of the three distinct areas-the preoperative unit, postanesthesia recovery unit, or Phase II discharge unit-the preceptor was scheduled to work. In the second group, trainees remained in one area, with various preceptors, until proficiency was achieved. All trainees (n = 25) were surveyed. FINDINGS: New registered nurses in the perianesthesia department prefer to remain in a single area until competency is achieved. CONCLUSIONS: Perianesthesia nursing has a distinct body of knowledge. Although conventional wisdom suggests that using a single preceptor for nursing orientation leads to better outcomes, our study indicates that allowing orientees to remain in one area until a level of competency is achieved may be more effective.
Assuntos
Capacitação em Serviço/organização & administração , Enfermagem Perioperatória , Competência Clínica , Humanos , Projetos Piloto , PreceptoriaRESUMO
Inhibition of spleen tyrosine kinase has attracted much attention as a mechanism for the treatment of cancers and autoimmune diseases such as asthma, rheumatoid arthritis, and systemic lupus erythematous. We report the structure-guided optimization of pyridazine amide spleen tyrosine kinase inhibitors. Early representatives of this scaffold were highly potent and selective but mutagenic in an Ames assay. An approach that led to the successful identification of nonmutagenic examples, as well as further optimization to compounds with reduced cardiovascular liabilities is described. Select pharmacokinetic and in vivo efficacy data are presented.
Assuntos
Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Piridazinas/síntese química , Piridazinas/farmacologia , Baço/enzimologia , Amidas/síntese química , Amidas/farmacologia , Animais , Biologia Computacional , Simulação por Computador , Desenho de Fármacos , Canais de Potássio Éter-A-Go-Go/efeitos dos fármacos , Humanos , Técnicas In Vitro , Camundongos , Microssomos Hepáticos/metabolismo , Modelos Moleculares , Conformação Molecular , Mutagênese/efeitos dos fármacos , Testes de Mutagenicidade , Inibidores de Proteínas Quinases/farmacocinética , Piridazinas/farmacocinética , Ratos , Baço/efeitos dos fármacos , Relação Estrutura-Atividade , Difração de Raios XRESUMO
INTRODUCTION: Spleen tyrosine kinase (SYK) is a key integrator of intracellular signals triggered by activated immunoreceptors, including Bcell receptors (BCR) and Fc receptors, which are important for the development and function of lymphoid cells. Given the clinical efficacy of Bcell depletion in the treatment of rheumatoid arthritis and multiple sclerosis, pharmacological modulation of Bcells using orally active small molecules that selectively target SYK presents an attractive alternative therapeutic strategy. METHODS: A SYK inhibitor was developed and assayed in various in vitro systems and in the mouse model of collagen-induced arthritis (mCIA). RESULTS: A novel ATP-competitive inhibitor of SYK, 6-[(1R,2S)-2-Amino-cyclohexylamino]-4-(5,6-dimethyl-pyridin-2-ylamino)-pyridazine-3-carboxylic acid amide, designated RO9021, with an adequate kinase selectivity profile and oral bioavailability, was developed. In addition to suppression of BCR signaling in human peripheral blood mononuclear cells (PBMC) and whole blood, FcγR signaling in human monocytes, and FcϵR signaling in human mast cells, RO9021 blocked osteoclastogenesis from mouse bone marrow macrophages in vitro. Interestingly, Toll-like Receptor (TLR) 9 signaling in human Bcells was inhibited by RO9021, resulting in decreased levels of plasmablasts, immunoglobulin (Ig) M and IgG upon B-cell differentiation. RO9021 also potently inhibited type I interferon production by human plasmacytoid dendritic cells (pDC) upon TLR9 activation. This effect is specific to TLR9 as RO9021 did not inhibit TLR4- or JAK-STAT-mediated signaling. Finally, oral administration of RO9021 inhibited arthritis progression in the mCIA model, with observable pharmacokinetics (PK)-pharmacodynamic (PD) correlation. CONCLUSIONS: Inhibition of SYK kinase activity impinges on various innate and adaptive immune responses. RO9021 could serve as a starting point for the development of selective SYK inhibitors for the treatment of inflammation-related and autoimmune-related disorders.
Assuntos
Imunidade Adaptativa/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Administração Oral , Aminopiridinas/química , Aminopiridinas/farmacologia , Animais , Artrite Experimental/metabolismo , Artrite Experimental/prevenção & controle , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/metabolismo , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Citometria de Fluxo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células Jurkat , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Modelos Moleculares , Estrutura Molecular , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Ligação Proteica , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/química , Estrutura Terciária de Proteína , Proteínas Tirosina Quinases/química , Proteínas Tirosina Quinases/metabolismo , Piridazinas/química , Piridazinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/administração & dosagem , Bibliotecas de Moléculas Pequenas/química , Quinase SykRESUMO
We describe the discovery of several pyrrolopyrazines as potent and selective Syk inhibitors and the efforts that eventually led to the desired improvements in physicochemical properties and human whole blood potencies. Ultimately, our mouse model revealed unexpected toxicity that precluded us from further advancing this series.
Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirazinas/síntese química , Pirróis/síntese química , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/enzimologia , Proteínas Sanguíneas/metabolismo , Cristalografia por Raios X , Humanos , Camundongos , Microssomos Hepáticos/metabolismo , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Pirazinas/farmacologia , Pirazinas/toxicidade , Pirróis/farmacologia , Pirróis/toxicidade , Relação Estrutura-Atividade , Quinase SykRESUMO
A novel approach to design selective spleen tyrosine kinase (Syk) inhibitors is described. Inhibition of spleen tyrosine kinase has attracted much attention as a mechanism for the treatment of autoimmune diseases such as asthma, rheumatoid arthritis, and SLE. Fostamatinib, a Syk inhibitor that successfully completed phase II clinical trials, also exhibits some undesirable side effects. More selective Syk inhibitors could offer safer, alternative treatments. Through a systematic evaluation of the kinome, we identified Pro455 and Asn457 in the Syk ATP binding site as a rare combination among sequence aligned kinases and hypothesized that optimizing the interaction between them and a Syk inhibitor molecule would impart high selectivity for Syk over other kinases. We report the structure-guided identification of three series of selective spleen tyrosine kinase inhibitors that support our hypothesis and offer useful guidance to other researchers in the field.