Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 69
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Genes Dev ; 35(11-12): 870-887, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34016692

RESUMO

Small cell lung carcinoma (SCLC) is among the most lethal of all solid tumor malignancies. In an effort to identify novel therapeutic approaches for this recalcitrant cancer type, we applied genome-scale CRISPR/Cas9 inactivation screens to cell lines that we derived from a murine model of SCLC. SCLC cells were particularly sensitive to the deletion of NEDD8 and other neddylation pathway genes. Genetic suppression or pharmacological inhibition of this pathway using MLN4924 caused cell death not only in mouse SCLC cell lines but also in patient-derived xenograft (PDX) models of pulmonary and extrapulmonary small cell carcinoma treated ex vivo or in vivo. A subset of PDX models were exceptionally sensitive to neddylation inhibition. Neddylation inhibition suppressed expression of major regulators of neuroendocrine cell state such as INSM1 and ASCL1, which a subset of SCLC rely upon for cell proliferation and survival. To identify potential mechanisms of resistance to neddylation inhibition, we performed a genome-scale CRISPR/Cas9 suppressor screen. Deletion of components of the COP9 signalosome strongly mitigated the effects of neddylation inhibition in small cell carcinoma, including the ability of MLN4924 to suppress neuroendocrine transcriptional program expression. This work identifies neddylation as a regulator of neuroendocrine cell state and potential therapeutic target for small cell carcinomas.


Assuntos
Carcinoma de Células Pequenas/terapia , Ciclopentanos , Neoplasias Pulmonares/terapia , Proteína NEDD8/metabolismo , Pirimidinas , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Complexo do Signalossomo COP9/genética , Carcinoma de Células Pequenas/fisiopatologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ciclopentanos/farmacologia , Ciclopentanos/uso terapêutico , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Xenoenxertos , Humanos , Neoplasias Pulmonares/fisiopatologia , Camundongos , Proteína NEDD8/genética , Células Neuroendócrinas/citologia , Células Neuroendócrinas/efeitos dos fármacos , Proteínas/genética , Proteínas/metabolismo , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Proteínas Repressoras/genética , Deleção de Sequência
2.
Genes Dev ; 34(17-18): 1210-1226, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32820040

RESUMO

Small cell lung cancer (SCLC) is an aggressive neuroendocrine cancer characterized by initial chemosensitivity followed by emergence of chemoresistant disease. To study roles for MYCN amplification in SCLC progression and chemoresistance, we developed a genetically engineered mouse model of MYCN-overexpressing SCLC. In treatment-naïve mice, MYCN overexpression promoted cell cycle progression, suppressed infiltration of cytotoxic T cells, and accelerated SCLC. MYCN overexpression also suppressed response to cisplatin-etoposide chemotherapy, with similar findings made upon MYCL overexpression. We extended these data to genetically perturb chemosensitive patient-derived xenograft (PDX) models of SCLC. In chemosensitive PDX models, overexpression of either MYCN or MYCL also conferred a switch to chemoresistance. To identify therapeutic strategies for MYCN-overexpressing SCLC, we performed a genome-scale CRISPR-Cas9 sgRNA screen. We identified the deubiquitinase USP7 as a MYCN-associated synthetic vulnerability. Pharmacological inhibition of USP7 resensitized chemoresistant MYCN-overexpressing PDX models to chemotherapy in vivo. Our findings show that MYCN overexpression drives SCLC chemoresistance and provide a therapeutic strategy to restore chemosensitivity.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pulmonares/genética , Proteína Proto-Oncogênica N-Myc/metabolismo , Peptidase 7 Específica de Ubiquitina/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Xenoenxertos , Humanos , Neoplasias Pulmonares/enzimologia , Camundongos , Proteína Proto-Oncogênica N-Myc/genética , Carcinoma de Pequenas Células do Pulmão/enzimologia , Carcinoma de Pequenas Células do Pulmão/genética
3.
Genes Dev ; 30(11): 1289-99, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27298335

RESUMO

Small cell lung cancer (SCLC) is a devastating neuroendocrine carcinoma. MYCL (L-Myc) is frequently amplified in human SCLC, but its roles in SCLC progression are poorly understood. We isolated preneoplastic neuroendocrine cells from a mouse model of SCLC and found that ectopic expression of L-Myc, c-Myc, or N-Myc conferred tumor-forming capacity. We focused on L-Myc, which promoted pre-rRNA synthesis and transcriptional programs associated with ribosomal biogenesis. Deletion of Mycl in two genetically engineered models of SCLC resulted in strong suppression of SCLC. The high degree of suppression suggested that L-Myc may constitute a therapeutic target for a broad subset of SCLC. We then used an RNA polymerase I inhibitor to target rRNA synthesis in an autochthonous Rb/p53-deleted mouse SCLC model and found significant tumor inhibition. These data reveal that activation of RNA polymerase I by L-Myc and other MYC family proteins provides an axis of vulnerability for this recalcitrant cancer.


Assuntos
Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Polimerase I/metabolismo , Carcinoma de Pequenas Células do Pulmão/enzimologia , Carcinoma de Pequenas Células do Pulmão/genética , Animais , Animais Geneticamente Modificados , Benzotiazóis/farmacologia , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Inativação Gênica , Neoplasias Pulmonares/fisiopatologia , Camundongos , Naftiridinas/farmacologia , Proteínas Proto-Oncogênicas c-myc/genética , RNA Polimerase I/antagonistas & inibidores , Ribossomos/metabolismo , Carcinoma de Pequenas Células do Pulmão/fisiopatologia , Carga Tumoral/efeitos dos fármacos , Células Tumorais Cultivadas
4.
Genes Dev ; 25(16): 1734-45, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21816922

RESUMO

The miR-17~92 cluster is a potent microRNA-encoding oncogene. Here, we show that miR-17~92 synergizes with loss of Rb family members to promote retinoblastoma. We observed miR-17~92 genomic amplifications in murine retinoblastoma and high expression of miR-17~92 in human retinoblastoma. While miR-17~92 was dispensable for mouse retinal development, miR-17~92 overexpression, together with deletion of Rb and p107, led to rapid emergence of retinoblastoma with frequent metastasis to the brain. miR-17~92 oncogenic function in retinoblastoma was not mediated by a miR-19/PTEN axis toward apoptosis suppression, as found in lymphoma/leukemia models. Instead, miR-17~92 increased the proliferative capacity of Rb/p107-deficient retinal cells. We found that deletion of Rb family members led to compensatory up-regulation of the cyclin-dependent kinase inhibitor p21Cip1. miR-17~92 overexpression counteracted p21Cip1 up-regulation, promoted proliferation, and drove retinoblastoma formation. These results demonstrate that the oncogenic determinants of miR-17~92 are context-specific and provide new insights into miR-17~92 function as an RB-collaborating gene in cancer.


Assuntos
MicroRNAs/genética , Mutação , Proteína do Retinoblastoma/genética , Retinoblastoma/genética , Transdução de Sinais/genética , Animais , Animais Recém-Nascidos , Linhagem Celular Tumoral , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Família Multigênica , Análise de Sequência com Séries de Oligonucleotídeos , Oligonucleotídeos Antissenso/genética , Gravidez , Retina/embriologia , Retina/crescimento & desenvolvimento , Retina/metabolismo , Retinoblastoma/metabolismo , Retinoblastoma/patologia , Proteína do Retinoblastoma/metabolismo , Proteína p107 Retinoblastoma-Like/genética , Proteína p107 Retinoblastoma-Like/metabolismo
5.
J Immunol ; 197(11): 4493-4503, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27799309

RESUMO

Lung cancer, the leading cause of cancer-related deaths worldwide, is a heterogeneous disease comprising multiple histologic subtypes that harbor disparate mutational profiles. Immune-based therapies have shown initial promise in the treatment of lung cancer patients but are limited by low overall response rates. We sought to determine whether the host immune response to lung cancer is dictated, at least in part, by histologic and genetic differences, because such correlations would have important clinical ramifications. Using mouse models of lung cancer, we show that small cell lung cancer (SCLC) and lung adenocarcinoma (ADCA) exhibit unique immune cell composition of the tumor microenvironment. The total leukocyte content was markedly reduced in SCLC compared with lung ADCA, which was validated in human lung cancer specimens. We further identified key differences in immune cell content using three models of lung ADCA driven by mutations in Kras, p53, and Egfr Although Egfr-mutant cancers displayed robust myeloid cell recruitment, they failed to mount a CD8+ immune response. In contrast, Kras-mutant tumors displayed significant expansion of multiple immune cell types, including CD8+ cells, regulatory T cells, IL-17A-producing lymphocytes, and myeloid cells. A human tissue microarray annotated for KRAS and EGFR mutations validated the finding of reduced CD8+ content in human lung ADCA. Taken together, these findings establish a strong foundational knowledge of the immune cell contexture of lung ADCA and SCLC and suggest that molecular and histological traits shape the host immune response to cancer.


Assuntos
Adenocarcinoma/imunologia , Linfócitos T CD8-Positivos/imunologia , Neoplasias Pulmonares/imunologia , Proteínas de Neoplasias/imunologia , Carcinoma de Pequenas Células do Pulmão/imunologia , Linfócitos T Reguladores/imunologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Linfócitos T CD8-Positivos/patologia , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Transgênicos , Mutação , Proteínas de Neoplasias/genética , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/patologia , Linfócitos T Reguladores/patologia
6.
Genes Chromosomes Cancer ; 56(3): 231-242, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27750399

RESUMO

Several murine retinoblastoma models have been generated by deleting the genes encoding for retinoblastoma susceptibility protein pRb and one of its family members p107 or p130. In Rb-/- p107-/- retinoblastomas, somatic copy number alterations (SCNAs) like Mdm2 amplification or Cdkn2a deletion targeting the p53-pathway occur, which is uncommon for human retinoblastoma. In our study, we determined SCNAs in retinoblastomas developing in Rb-/- p130-/- mice and compared this to murine Rb-/- p107-/- tumors and human tumors. Chimeric mice were made by injection of 129/Ola-derived Rb-/- p130-/- embryonic stem cells into wild type C57BL/6 blastocysts. SCNAs of retinoblastoma samples were determined by low-coverage (∼0.5×) whole genome sequencing. In Rb-/- p130-/- tumors, SCNAs included gain of chromosomes 1 (3/23 tumors), 8 (1/23 tumors), 10 (1/23 tumors), 11 (2/23 tumors), and 12 (4/23 tumors), which could be mapped to frequently altered chromosomes in human retinoblastomas. While the altered chromosomes in Rb-/- p130-/- tumors were similar to those in Rb-/- p107-/- tumors, the alteration frequencies were much lower in Rb-/- p130-/- tumors. Most of the Rb-/- p130-/- tumors (16/23 tumors, 70%) were devoid of SCNAs, in strong contrast to Rb-/- p107-/- tumors, which were never (0/15 tumors) SCNA-devoid. Similarly, to human retinoblastoma, increased age at diagnosis significantly correlated with increased SCNA frequencies. Additionally, focal loss of Cdh11 was observed in one Rb-/- p130-/- tumor, which enforces studies in human retinoblastoma that identified CDH11 as a retinoblastoma suppressor. Moreover, based on a comparison of genes altered in human and murine retinoblastoma, we suggest exploring the role of HMGA1 and SRSF3 in retinoblastoma development. © 2016 Wiley Periodicals, Inc.


Assuntos
Biomarcadores Tumorais/genética , Variações do Número de Cópias de DNA/genética , Proteína p107 Retinoblastoma-Like/fisiologia , Proteína p130 Retinoblastoma-Like/fisiologia , Retinoblastoma/genética , Animais , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Feminino , Genoma , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
7.
Dent Update ; 44(1): 53-4, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29172311

RESUMO

This is a case of a patient presenting to his general dental practitioner (GDP) with altered sensation in his lower lip with no obvious cause. Due to a prompt referral, the patient was investigated and diagnosed with an extramedullary presentation of multiple myeloma. A numb lip can present in general dental practice, although this is not common. There are several causes, for example, dental infection or fractured mandible. Clinical relevance: It is very important for the dental practitioner to recognize when there could be a potential sinister underlying cause and prompt referral, under the two week rule referral system, is indicated


Assuntos
Mieloma Múltiplo/secundário , Neoplasias de Tecidos Moles/secundário , Idoso , Humanos , Hipestesia/etiologia , Lábio , Masculino , Mandíbula , Mieloma Múltiplo/complicações , Mieloma Múltiplo/diagnóstico , Neoplasias de Tecidos Moles/complicações , Neoplasias de Tecidos Moles/diagnóstico
8.
J Gen Intern Med ; 29 Suppl 2: S579-88, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24715388

RESUMO

BACKGROUND: Many organizations rely on quality improvement collaboratives (QICs) to facilitate Patient-Centered Medical Home (PCMH) implementation, and there is a trend toward conducting QIC activities virtually to reduce costs and expand their reach. However, the evidence base for QICs is limited; questions remain about how QICs operate, why they succeed or fail, and how they are experienced by participants. OBJECTIVE: We surveyed participants in an innovative Virtual Collaborative (VC) designed to support PCMH implementation within one Veterans Integrated Service Network, to understand why and for whom the VC was more/less effective and identify opportunities for improvement. DESIGN: This anonymous online survey was designed to assess participants' views on the VC's usefulness, impact, and acceptability, and to explore variations by role, practice setting, prior training, and overall engagement in VC activities. PARTICIPANTS: Respondents were 353 primary care staff, including providers, nurses, and support staff. MEASURES/APPROACH: The survey comprised 32 structured and three free-response items. Structured items assessed participation in and perceived usefulness of VC activities; perceived acceptability of the training format; overall perceived impact; and basic demographics. Responses were dichotomized and compared using Chi-square tests. Free-response items inviting constructive criticism of the VC were coded and summarized to identify themes and illustrative quotes. RESULTS: The VC most benefited respondents with prior PCMH training and those who fully participated in VC activities. Respondents especially valued the opportunity to share experiences with other teams. Non-providers and those new to PCMH felt learning content did not meet their needs. Reported barriers to full participation included staffing constraints, insufficient and/or unprotected time, and inadequate leadership support. CONCLUSIONS: Our study offers practical lessons for others considering a virtual collaborative model for PCMH spread. Findings contribute to the evidence base for QICs overall and virtual QICs in particular, highlighting the value of seeking input from "the trenches."


Assuntos
Comportamento Cooperativo , Coleta de Dados/métodos , Assistência Centrada no Paciente/métodos , Atenção Primária à Saúde/métodos , United States Department of Veterans Affairs , Interface Usuário-Computador , Humanos , Estados Unidos
9.
Oncogene ; 43(7): 457-469, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38191672

RESUMO

Small cell lung cancer (SCLC) remains the most fatal form of lung cancer, with patients in dire need of new and effective therapeutic approaches. Modeling SCLC in an immunocompetent host is essential for understanding SCLC pathogenesis and ultimately discovering and testing new experimental therapeutic strategies. Human SCLC is characterized by near universal genetic loss of the RB1 and TP53 tumor suppressor genes. Twenty years ago, the first genetically-engineered mouse model (GEMM) of SCLC was generated using conditional deletion of both Rb1 and Trp53 in the lungs of adult mice. Since then, several other GEMMs of SCLC have been developed coupling genomic alterations found in human SCLC with Rb1 and Trp53 deletion. Here we summarize how GEMMs of SCLC have contributed significantly to our understanding of the disease in the past two decades. We also review recent advances in modeling SCLC in mice that allow investigators to bypass limitations of the previous generation of GEMMs while studying new genes of interest in SCLC. In particular, CRISPR/Cas9-mediated somatic gene editing can accelerate how new genes of interest are functionally interrogated in SCLC tumorigenesis. Notably, the development of allograft models and precancerous precursor models from SCLC GEMMs provides complementary approaches to GEMMs to study tumor cell-immune microenvironment interactions and test new therapeutic strategies to enhance response to immunotherapy. Ultimately, the new generation of SCLC models can accelerate research and help develop new therapeutic strategies for SCLC.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Animais , Camundongos , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Neoplasias Pulmonares/patologia , Pulmão/patologia , Edição de Genes , Transformação Celular Neoplásica , Microambiente Tumoral/genética
10.
Sci Adv ; 10(15): eadk2082, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38598634

RESUMO

We report an approach for cancer phenotyping based on targeted sequencing of cell-free DNA (cfDNA) for small cell lung cancer (SCLC). In SCLC, differential activation of transcription factors (TFs), such as ASCL1, NEUROD1, POU2F3, and REST defines molecular subtypes. We designed a targeted capture panel that identifies chromatin organization signatures at 1535 TF binding sites and 13,240 gene transcription start sites and detects exonic mutations in 842 genes. Sequencing of cfDNA from SCLC patient-derived xenograft models captured TF activity and gene expression and revealed individual highly informative loci. Prediction models of ASCL1 and NEUROD1 activity using informative loci achieved areas under the receiver operating characteristic curve (AUCs) from 0.84 to 0.88 in patients with SCLC. As non-SCLC (NSCLC) often transforms to SCLC following targeted therapy, we applied our framework to distinguish NSCLC from SCLC and achieved an AUC of 0.99. Our approach shows promising utility for SCLC subtyping and transformation monitoring, with potential applicability to diverse tumor types.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Ácidos Nucleicos Livres , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Carcinoma de Pequenas Células do Pulmão/metabolismo , Neoplasias Pulmonares/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Sequências Reguladoras de Ácido Nucleico , Regulação Neoplásica da Expressão Gênica
11.
Cell Rep ; 42(8): 113016, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37597186

RESUMO

Small cell lung cancers (SCLCs) rapidly resist cytotoxic chemotherapy and immune checkpoint inhibitor (ICI) treatments. New, non-cross-resistant therapies are thus needed. SCLC cells are committed into neuroendocrine lineage then maturation arrested. Implicating DNA methyltransferase 1 (DNMT1) in the maturation arrests, we find (1) the repression mark methylated CpG, written by DNMT1, is retained at suppressed neuroendocrine-lineage genes, even as other repression marks are erased; (2) DNMT1 is recurrently amplified, whereas Ten-Eleven-Translocation 2 (TET2), which functionally opposes DNMT1, is deleted; (3) DNMT1 is recruited into neuroendocrine-lineage master transcription factor (ASCL1, NEUROD1) hubs in SCLC cells; and (4) DNMT1 knockdown activated ASCL1-target genes and released SCLC cell-cycling exits by terminal lineage maturation, which are cycling exits that do not require the p53/apoptosis pathway used by cytotoxic chemotherapy. Inhibiting DNMT1/corepressors with clinical compounds accordingly extended survival of mice with chemorefractory and ICI-refractory, p53-null, disseminated SCLC. Lineage commitment of SCLC cells can hence be leveraged into non-cytotoxic therapy able to treat chemo/ICI-refractory SCLC.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Animais , Camundongos , Proteína Supressora de Tumor p53/genética , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Ciclo Celular , Divisão Celular , Neoplasias Pulmonares/tratamento farmacológico
12.
Sci Transl Med ; 15(678): eadd8469, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36630482

RESUMO

Small cell lung cancer (SCLC) elicits the generation of autoantibodies that result in unique paraneoplastic neurological syndromes. The mechanistic basis for the formation of such autoantibodies is largely unknown but is key to understanding their etiology. We developed a high-dimensional technique that enables detection of autoantibodies in complex with native antigens directly from patient plasma. Here, we used our platform to screen 1009 human plasma samples for 3600 autoantibody-antigen complexes, finding that plasma from patients with SCLC harbors, on average, fourfold higher disease-specific autoantibody signals compared with plasma from patients with other cancers. Across three independent SCLC cohorts, we identified a set of common but previously unknown autoantibodies that are produced in response to both intracellular and extracellular tumor antigens. We further characterized several disease-specific posttranslational modifications within extracellular proteins targeted by these autoantibodies, including citrullination, isoaspartylation, and cancer-specific glycosylation. Because most patients with SCLC have metastatic disease at diagnosis, we queried whether these autoantibodies could be used for SCLC early detection. We created a risk prediction model using five autoantibodies with an average area under the curve of 0.84 for the three cohorts that improved to 0.96 by incorporating cigarette smoke consumption in pack years. Together, our findings provide an innovative approach to identify circulating autoantibodies in SCLC with mechanistic insight into disease-specific immunogenicity and clinical utility.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Neoplasias Pulmonares/patologia , Autoanticorpos , Processamento de Proteína Pós-Traducional
13.
Clin Cancer Res ; 28(20): 4551-4564, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-35920742

RESUMO

PURPOSE: The addition of immune checkpoint blockade (ICB) to platinum/etoposide chemotherapy changed the standard of care for small cell lung cancer (SCLC) treatment. However, ICB addition only modestly improved clinical outcomes, likely reflecting the high prevalence of an immunologically "cold" tumor microenvironment in SCLC, despite high mutational burden. Nevertheless, some patients clearly benefit from ICB and recent reports have associated clinical responses to ICB in SCLC with (i) decreased neuroendocrine characteristics and (ii) activation of NOTCH signaling. We previously showed that inhibition of the lysine-specific demethylase 1a (LSD1) demethylase activates NOTCH and suppresses neuroendocrine features of SCLC, leading us to investigate whether LSD1 inhibition would enhance the response to PD-1 inhibition in SCLC. EXPERIMENTAL DESIGN: We employed a syngeneic immunocompetent model of SCLC, derived from a genetically engineered mouse model harboring Rb1/Trp53 inactivation, to investigate combining the LSD1 inhibitor bomedemstat with anti-PD-1 therapy. In vivo experiments were complemented by cell-based studies in murine and human models. RESULTS: Bomedemstat potentiated responses to PD-1 inhibition in a syngeneic model of SCLC, resulting in increased CD8+ T-cell infiltration and strong tumor growth inhibition. Bomedemstat increased MHC class I expression in mouse SCLC tumor cells in vivo and augmented MHC-I induction by IFNγ and increased killing by tumor-specific T cells in cell culture. CONCLUSIONS: LSD1 inhibition increased MHC-I expression and enhanced responses to PD-1 inhibition in vivo, supporting a new clinical trial to combine bomedemstat with standard-of-care PD-1 axis inhibition in SCLC.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Animais , Morte Celular , Inibidores Enzimáticos/uso terapêutico , Etoposídeo/uso terapêutico , Histona Desmetilases/metabolismo , Humanos , Inibidores de Checkpoint Imunológico , Neoplasias Pulmonares/patologia , Lisina/uso terapêutico , Camundongos , Platina/uso terapêutico , Carcinoma de Pequenas Células do Pulmão/patologia , Microambiente Tumoral
14.
Nat Commun ; 13(1): 7475, 2022 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463275

RESUMO

Cell-free DNA (cfDNA) has the potential to inform tumor subtype classification and help guide clinical precision oncology. Here we develop Griffin, a framework for profiling nucleosome protection and accessibility from cfDNA to study the phenotype of tumors using as low as 0.1x coverage whole genome sequencing data. Griffin employs a GC correction procedure tailored to variable cfDNA fragment sizes, which generates a better representation of chromatin accessibility and improves the accuracy of cancer detection and tumor subtype classification. We demonstrate estrogen receptor subtyping from cfDNA in metastatic breast cancer. We predict estrogen receptor subtype in 139 patients with at least 5% detectable circulating tumor DNA with an area under the receive operator characteristic curve (AUC) of 0.89 and validate performance in independent cohorts (AUC = 0.96). In summary, Griffin is a framework for accurate tumor subtyping and can be generalizable to other cancer types for precision oncology applications.


Assuntos
Ácidos Nucleicos Livres , Neoplasias , Humanos , Ácidos Nucleicos Livres/genética , Nucleossomos/genética , Neoplasias/diagnóstico , Neoplasias/genética , Receptores de Estrogênio , Medicina de Precisão
15.
Healthc (Amst) ; 8 Suppl 1: 100485, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34175098

RESUMO

BACKGROUND: Compared to White patients in the United States, Black patients have a higher prevalence of hypertension and more severe forms of this condition. OBJECTIVE: To decrease racial disparities in blood pressure (BP) control among Black veterans with severe hypertension within a regional network of Veterans Affairs Medical Centers (VAMCs). METHODS: Health system leaders, clinicians, and health services researchers collaborated on a 12-month quality improvement (QI) project to: (1) examine project implementation and the QI strategies used to improve BP control and (2) assess the effect of the initiative on Black-White differences in BP control among veterans with severe hypertension. RESULTS: Within 9 participating VAMCs, the most frequently used QI strategies involved provider education (n=9), provider audit and feedback (n=8), and health care team change (n=7). Among 141,124 veterans with a diagnosis of hypertension, 9,913 had severe hypertension [2,533 (25.6%) Black and 7380 (74.4%) White]. Over the course of the project, the proportion of Black veterans with severe hypertension decreased from 7.5% to 6.6% (p=.002) and the racial difference in proportions for this condition decreased 0.9 percentage points, from 2.9% to 2.0% (p=.01). CONCLUSIONS: A multicenter, equity-focused QI project in VA reduced the proportion of Black veterans with severe hypertension and ameliorated observed racial disparities for this condition. Embedding health services researchers within a QI team facilitated an evaluation of the processes and effectiveness of our initiative, providing a successful model for QI within a learning health care system.


Assuntos
Hipertensão , Veteranos , Pressão Sanguínea , Humanos , Hipertensão/terapia , Grupos Raciais , Estados Unidos , United States Department of Veterans Affairs
16.
Elife ; 102021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34236315

RESUMO

MGA, a transcription factor and member of the MYC network, is mutated or deleted in a broad spectrum of malignancies. As a critical test of a tumor suppressive role, we inactivated Mga in two mouse models of non-small cell lung cancer using a CRISPR-based approach. MGA loss significantly accelerated tumor growth in both models and led to de-repression of non-canonical Polycomb ncPRC1.6 targets, including genes involved in metastasis and meiosis. Moreover, MGA deletion in human lung adenocarcinoma lines augmented invasive capabilities. We further show that MGA-MAX, E2F6, and L3MBTL2 co-occupy thousands of promoters and that MGA stabilizes these ncPRC1.6 subunits. Lastly, we report that MGA loss also induces a pro-growth effect in human colon organoids. Our studies establish MGA as a bona fide tumor suppressor in vivo and suggest a tumor suppressive mechanism in adenocarcinomas resulting from widespread transcriptional attenuation of MYC and E2F target genes mediated by MGA-MAX associated with a non-canonical Polycomb complex.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Repressão Epigenética , Proteínas do Grupo Polycomb/genética , Adenocarcinoma de Pulmão/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Humanos , Masculino , Camundongos , Invasividade Neoplásica/genética , Proteínas do Grupo Polycomb/metabolismo
17.
Bioorg Med Chem Lett ; 20(4): 1368-72, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20097071

RESUMO

A pharmacophore model was built, based on known CGRP receptor antagonists, and this was used to aid the identification of novel leads. Analogues were designed, modelled and synthesised which incorporated alternative 'LHS' fragments linked via either an amide or urea to a privileged 'RHS' fragment commonly found in CGRP receptor antagonists. As a result a novel series of oxadiazole CGRP receptor antagonists has been identified and the subsequent optimisation to enhance both potency and bioavailability is presented.


Assuntos
Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina , Desenho de Fármacos , Transtornos de Enxaqueca/tratamento farmacológico , Oxidiazóis/síntese química , Oxidiazóis/uso terapêutico , Administração Oral , Animais , Modelos Moleculares , Estrutura Molecular , Oxidiazóis/química , Ratos
18.
ACS Med Chem Lett ; 11(9): 1678-1687, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32945812

RESUMO

Drugs that block voltage-gated sodium channels (NaVs) have utility in treating conditions including pain, epilepsy, and cardiac arrhythmias and as anesthetics (Lancet Neurol.20109413424; Expert Opin. Ther. Pat.201020755779). The identification of compounds with improved efficacy and safety is a key aim for the discovery of improved NaV blocking drugs (Comprehensive Medicinal Chemistry III; (Elsevier, 2017; pp 131-175). We report the identification of a novel class of brain penetrant and voltage-gated sodium channel blockers, leading to the discovery of vixotrigine, a use-dependent sodium channel blocker with activity in in vivo models of pain. Vixotrigine has excellent physiocochemical properties for drug development, and both preclinical and clinical data support a safety profile suitable for potential use in neuropathic pain and other conditions. It has shown efficacy in a Phase II study for pain associated with trigeminal neuralgia.

19.
Cancer Cell ; 38(1): 97-114.e7, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32470392

RESUMO

Small cell lung cancer (SCLC) is a highly aggressive and lethal neoplasm. To identify candidate tumor suppressors we applied CRISPR/Cas9 gene inactivation screens to a cellular model of early-stage SCLC. Among the top hits was MAX, the obligate heterodimerization partner for MYC family proteins that is mutated in human SCLC. Max deletion increases growth and transformation in cells and dramatically accelerates SCLC progression in an Rb1/Trp53-deleted mouse model. In contrast, deletion of Max abrogates tumorigenesis in MYCL-overexpressing SCLC. Max deletion in SCLC resulted in derepression of metabolic genes involved in serine and one-carbon metabolism. By increasing serine biosynthesis, Max-deleted cells exhibit resistance to serine depletion. Thus, Max loss results in metabolic rewiring and context-specific tumor suppression.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Modelos Animais de Doenças , Neoplasias Pulmonares/genética , Carcinoma de Pequenas Células do Pulmão/genética , Proteínas Supressoras de Tumor/genética , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Células Cultivadas , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Células Hep G2 , Humanos , Células K562 , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/metabolismo , Camundongos Knockout , Camundongos Transgênicos , Carcinoma de Pequenas Células do Pulmão/metabolismo , Proteínas Supressoras de Tumor/metabolismo
20.
Clin Cancer Res ; 26(7): 1667-1677, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31806643

RESUMO

PURPOSE: Small-cell neuroendocrine prostate cancer (SCNPC) exhibits an aggressive clinical course and incidence rates seem to be increasing following resistance to potent androgen receptor (AR) antagonists. Currently, treatment options are limited and few model systems are available to identify new approaches for treatment. We sought to evaluate commonalities between SCNPC and other aggressive neuroendocrine carcinomas to identify therapeutic targets. EXPERIMENTAL DESIGN: We generated whole transcriptome RNA-sequencing data from AR-active prostate cancers (ARPCs) and SCNPCs from tumors collected at rapid autopsy and two other neuroendocrine carcinomas, Merkel cell carcinoma (MCC), and small-cell lung cancer. We performed cross-tumor comparisons to identify conserved patterns of expression of druggable targets. We tested inhibitors to highly upregulated drug targets in a panel of prostate cancer cell lines and in vivo patient-derived xenograft (PDX) models. RESULTS: We identified BCL2 as highly upregulated in SCNPC compared with ARPC. Inhibitors targeting BCL2 induced apoptotic cell death in SCNPC cell lines at nanomolar concentrations while ARPC cell lines were resistant. Treatment with the BCL2 inhibitor navitoclax leads to a reduction of growth of SCNPC PDX tumors in vivo, whereas ARPC PDX models were more resistant. We identified Wee1 as a second druggable target upregulated in SCNPC. Treatment with the combination of navitoclax and the Wee1 inhibitor AZD-1775 repressed the growth of SCNPC PDX resistant to single-agent BCL2 inhibitors. CONCLUSIONS: The combination of BCL2 and Wee1 inhibition presents a novel therapeutic strategy for the treatment of SCNPC.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Antineoplásicos/farmacologia , Carcinoma Neuroendócrino/patologia , Carcinoma de Células Pequenas/patologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Neoplasias de Próstata Resistentes à Castração/patologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Animais , Apoptose , Carcinoma Neuroendócrino/tratamento farmacológico , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/metabolismo , Carcinoma de Células Pequenas/tratamento farmacológico , Carcinoma de Células Pequenas/genética , Carcinoma de Células Pequenas/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA