RESUMO
Monocytic acute myeloid leukemia (AML) responds poorly to current treatments, including venetoclax-based therapy. We conducted in vivo and in vitro CRISPR-Cas9 library screenings using a mouse monocytic AML model and identified SETDB1 and its binding partners (ATF7IP and TRIM33) as crucial tumor promoters in vivo. The growth-inhibitory effect of Setdb1 depletion in vivo is dependent mainly on natural killer (NK) cell-mediated cytotoxicity. Mechanistically, SETDB1 depletion upregulates interferon-stimulated genes and NKG2D ligands through the demethylation of histone H3 Lys9 at the enhancer regions, thereby enhancing their immunogenicity to NK cells and intrinsic apoptosis. Importantly, these effects are not observed in non-monocytic leukemia cells. We also identified the expression of myeloid cell nuclear differentiation antigen (MNDA) and its murine counterpart Ifi203 as biomarkers to predict the sensitivity of AML to SETDB1 depletion. Our study highlights the critical and selective role of SETDB1 in AML with granulo-monocytic differentiation and underscores its potential as a therapeutic target for current unmet needs.
RESUMO
Aberrant DNA methylation patterns are a prominent feature of cancer. Methylation of DNA is mediated by the DNA methyltransferase (DNMT) protein family, which regulates de novo (DNMT3A and DNMT3B) and maintenance (DNMT1) methylation. Mutations in DNMT3A are observed in approximately 22% of acute myeloid leukemia (AML). We hypothesized that DNMT1 or DNMT3B could function as a synthetic lethal therapeutic strategy for DNMT3A-mutant AML. CRISPR-Cas9 tiling screens were performed to identify functional domains within DNMT1/DNMT3B that exhibited greater dependencies in DNMT3A mutant versus wild-type cell lines. Although increased sensitivity to DNMT1 mutation was observed in some DNMT3A mutant cellular models tested, the subtlety of these results prevents us from basing any conclusions on a synthetic lethal relationship between DNMT1 and DNMT3A. Our data suggests that a therapeutic window for DNMT1 methyltransferase inhibition in DNMT3A-driven AML may exist, but validation in more biologically relevant models is required.
Assuntos
Leucemia Mieloide Aguda , Metiltransferases , Humanos , Metiltransferases/genética , DNA Metiltransferase 3A , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Leucemia Mieloide Aguda/genética , Mutação , DNARESUMO
Peripheral T-cell lymphomas (PTCL) are aggressive diseases with poor response to chemotherapy and dismal survival. Identification of effective strategies to target PTCL biology represents an urgent need. Here we report that PTCL are sensitive to transcription-targeting drugs, and, in particular, to THZ1, a covalent inhibitor of cyclin-dependent kinase 7 (CDK7). The STAT-signalling pathway is highly vulnerable to THZ1 even in PTCL cells that carry the activating STAT3 mutation Y640F. In mutant cells, CDK7 inhibition decreases STAT3 chromatin binding and expression of highly transcribed target genes like MYC, PIM1, MCL1, CD30, IL2RA, CDC25A and IL4R. In surviving cells, THZ1 decreases the expression of STAT-regulated anti-apoptotic BH3 family members MCL1 and BCL-XL sensitizing PTCL cells to BH3 mimetic drugs. Accordingly, the combination of THZ1 and the BH3 mimetic obatoclax improves lymphoma growth control in a primary PTCL ex vivo culture and in two STAT3-mutant PTCL xenografts, delineating a potential targeted agent-based therapeutic option for these patients.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Quinases Ciclina-Dependentes/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Linfoma de Células T/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Cromatina/metabolismo , Quinases Ciclina-Dependentes/antagonistas & inibidores , Feminino , Mutação com Ganho de Função , Humanos , Indóis , Linfoma de Células T/genética , Linfoma de Células T/patologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fenilenodiaminas/farmacologia , Fenilenodiaminas/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Pirróis/farmacologia , Pirróis/uso terapêutico , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transcrição Gênica/efeitos dos fármacos , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto , Quinase Ativadora de Quinase Dependente de CiclinaRESUMO
Anaplastic large cell lymphomas (ALCL) represent a peripheral T-cell lymphoma subgroup, stratified based on the presence or absence of anaplastic lymphoma kinase (ALK) chimeras. Although ALK-positive ALCLs have a more favorable outcome than ALK-negative ALCL, refractory and/or relapsed forms are common and novel treatments are needed. Here we investigated the therapeutic potential of a novel bromodomain inhibitor, OTX015/MK-8628 in ALK-positive ALCLs.The effects of OTX015 on a panel of ALK+ ALCL cell lines was evaluated in terms of proliferation, cell cycle and downstream signaling, including gene expression profiling analyses. Synergy was tested with combination targeted therapies.Bromodomain inhibition with OTX015 led primarily to ALCL cell cycle arrest in a dose-dependent manner, along with downregulation of MYC and its downstream regulated genes. MYC overexpression did not compensate this OTX015-mediated phenotype. Transcriptomic analysis of OTX015-treated ALCL cells identified a gene signature common to various hematologic malignancies treated with bromodomain inhibitors, notably large cell lymphoma. OTX015-modulated genes included transcription factors (E2F2, NFKBIZ, FOS, JUNB, ID1, HOXA5 and HOXC6), members of multiple signaling pathways (ITK, PRKCH, and MKNK2), and histones (clusters 1-3). Combination of OTX015 with the Bruton's tyrosine kinase (BTK) inhibitor ibrutinib led to cell cycle arrest then cell death, and combination with suboptimal doses of the ALK inhibitor CEP28122 caused cell cycle arrest. When OTX015 was associated with GANT61, a selective GLI1/2 inhibitor, C1156Y-resistant ALK ALCL growth was impaired.These findings support OTX015 clinical trials in refractory ALCL in combination with inhibitors of interleukin-2-inducible kinase or SHH/GLI1.
Assuntos
Acetanilidas/farmacologia , Antineoplásicos/farmacologia , Biomarcadores Tumorais/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Receptores Proteína Tirosina Quinases/genética , Quinase do Linfoma Anaplásico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Humanos , Concentração Inibidora 50 , Linfoma Anaplásico de Células Grandes/genética , Linfoma Anaplásico de Células Grandes/patologia , Fenótipo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , TranscriptomaRESUMO
The anaplastic lymphoma kinase (ALK) gene is a member of the insulin receptor superfamily and it has been associated with more than twenty distinct chimera, including established drivers of several human cancers. Multiple clinical trials have proven that the pharmacological inhibition of ALK signaling leads to remarkable clinical improvement and improves the quality of life of ALK+ cancer patients. Crizotinib was the first ALKi to achieve approval from the Food and Drug Administration, although additional compounds are now moving into diversified clinical trials.
Assuntos
Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Quinase do Linfoma Anaplásico , Animais , Antineoplásicos/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Inibidores de Proteínas Quinases/uso terapêutico , Receptores Proteína Tirosina Quinases/metabolismoRESUMO
A systematic characterization of the genetic alterations driving ALCLs has not been performed. By integrating massive sequencing strategies, we provide a comprehensive characterization of driver genetic alterations (somatic point mutations, copy number alterations, and gene fusions) in ALK(-) ALCLs. We identified activating mutations of JAK1 and/or STAT3 genes in â¼20% of 88 [corrected] ALK(-) ALCLs and demonstrated that 38% of systemic ALK(-) ALCLs displayed double lesions. Recurrent chimeras combining a transcription factor (NFkB2 or NCOR2) with a tyrosine kinase (ROS1 or TYK2) were also discovered in WT JAK1/STAT3 ALK(-) ALCL. All these aberrations lead to the constitutive activation of the JAK/STAT3 pathway, which was proved oncogenic. Consistently, JAK/STAT3 pathway inhibition impaired cell growth in vitro and in vivo.