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1.
Nat Commun ; 11(1): 4940, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009411

RESUMO

The HUSH complex represses retroviruses, transposons and genes to maintain the integrity of vertebrate genomes. HUSH regulates deposition of the epigenetic mark H3K9me3, but how its three core subunits - TASOR, MPP8 and Periphilin - contribute to assembly and targeting of the complex remains unknown. Here, we define the biochemical basis of HUSH assembly and find that its modular architecture resembles the yeast RNA-induced transcriptional silencing complex. TASOR, the central HUSH subunit, associates with RNA processing components. TASOR is required for H3K9me3 deposition over LINE-1 repeats and repetitive exons in transcribed genes. In the context of previous studies, this suggests that an RNA intermediate is important for HUSH activity. We dissect the TASOR and MPP8 domains necessary for transgene repression. Structure-function analyses reveal TASOR bears a catalytically-inactive PARP domain necessary for targeted H3K9me3 deposition. We conclude that TASOR is a multifunctional pseudo-PARP that directs HUSH assembly and epigenetic regulation of repetitive genomic targets.


Assuntos
Elementos de DNA Transponíveis/genética , Epigênese Genética , Complexos Multiproteicos/metabolismo , Proteínas Nucleares/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Sequência de Aminoácidos , Antígenos de Neoplasias/metabolismo , Sítios de Ligação , Éxons/genética , Genoma , Células HEK293 , Células HeLa , Histonas/metabolismo , Humanos , Lisina/metabolismo , Espectroscopia de Ressonância Magnética , Metilação , NAD/metabolismo , Proteínas Nucleares/química , Fosfoproteínas/metabolismo , Ligação Proteica , Domínios Proteicos , RNA/metabolismo , Processamento Pós-Transcricional do RNA , Transcrição Genética
2.
Nat Commun ; 11(1): 4659, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938936

RESUMO

The αvß6 integrin plays a key role in the activation of transforming growth factor-ß (TGFß), a pro-fibrotic mediator that is pivotal to the development of idiopathic pulmonary fibrosis (IPF). We identified a selective small molecule αvß6 RGD-mimetic, GSK3008348, and profiled it in a range of disease relevant pre-clinical systems. To understand the relationship between target engagement and inhibition of fibrosis, we measured pharmacodynamic and disease-related end points. Here, we report, GSK3008348 binds to αvß6 with high affinity in human IPF lung and reduces downstream pro-fibrotic TGFß signaling to normal levels. In human lung epithelial cells, GSK3008348 induces rapid internalization and lysosomal degradation of the αvß6 integrin. In the murine bleomycin-induced lung fibrosis model, GSK3008348 engages αvß6, induces prolonged inhibition of TGFß signaling and reduces lung collagen deposition and serum C3M, a marker of IPF disease progression. These studies highlight the potential of inhaled GSK3008348 as an anti-fibrotic therapy.


Assuntos
Butiratos/farmacologia , Fibrose Pulmonar Idiopática/tratamento farmacológico , Integrinas/antagonistas & inibidores , Naftiridinas/farmacologia , Pirazóis/farmacologia , Pirrolidinas/farmacologia , Administração por Inalação , Animais , Antígenos de Neoplasias/metabolismo , Bleomicina/toxicidade , Butiratos/administração & dosagem , Butiratos/metabolismo , Butiratos/farmacocinética , Colágeno/metabolismo , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Humanos , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/patologia , Integrinas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Naftiridinas/administração & dosagem , Naftiridinas/metabolismo , Naftiridinas/farmacocinética , Pirazóis/administração & dosagem , Pirazóis/metabolismo , Pirazóis/farmacocinética , Pirrolidinas/administração & dosagem , Pirrolidinas/metabolismo , Pirrolidinas/farmacocinética , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Tomografia Computadorizada de Emissão de Fóton Único , Fator de Crescimento Transformador beta/metabolismo , Pesquisa Médica Translacional
3.
Nat Commun ; 11(1): 4835, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32973173

RESUMO

Immune checkpoint blockade therapies have shown clinical promise in a variety of cancers, but how tumor-infiltrating T cells are activated remains unclear. In this study, we explore the functions of PD-L1 on dendritic cells (DCs), which highly express PD-L1. We observe that PD-L1 on DC plays a critical role in limiting T cell responses. Type 1 conventional DCs are essential for PD-L1 blockade and they upregulate PD-L1 upon antigen uptake. Upregulation of PD-L1 on DC is mediated by type II interferon. While DCs are the major antigen presenting cells for cross-presenting tumor antigens to T cells, subsequent PD-L1 upregulation protects them from killing by cytotoxic T lymphocytes, yet dampens the antitumor responses. Blocking PD-L1 in established tumors promotes re-activation of tumor-infiltrating T cells for tumor control. Our study identifies a critical and dynamic role of PD-L1 on DC, which needs to be harnessed for better invigoration of antitumor immune responses.


Assuntos
Antígeno B7-H1/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Ativação Linfocitária , Animais , Antígenos de Neoplasias/metabolismo , Antígeno B7-H1/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Interferon gama/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T Citotóxicos/imunologia , Microambiente Tumoral/imunologia , Regulação para Cima
4.
PLoS One ; 15(8): e0237814, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804975

RESUMO

Schaaf-Yang syndrome (SYS) is a neurodevelopmental disorder caused by truncating variants in the paternal allele of MAGEL2, located in the Prader-Willi critical region, 15q11-q13. Although the phenotypes of SYS overlap those of Prader-Willi syndrome (PWS), including neonatal hypotonia, feeding problems, and developmental delay/intellectual disability, SYS patients show autism spectrum disorder and joint contractures, which are atypical phenotypes for PWS. Therefore, we hypothesized that the truncated Magel2 protein could potentially produce gain-of-function toxic effects. To test the hypothesis, we generated two engineered mouse models; one, an overexpression model that expressed the N-terminal region of Magel2 that was FLAG tagged with a strong ubiquitous promoter, and another, a genome-edited model that carried a truncating variant in Magel2 generated using the CRISPR/Cas9 system. In the overexpression model, all transgenic mice died in the fetal or neonatal period indicating embryonic or neonatal lethality of the transgene. Therefore, overexpression of the truncated Magel2 could show toxic effects. In the genome-edited model, we generated a mouse model carrying a frameshift variant (c.1690_1924del; p(Glu564Serfs*130)) in Magel2. Model mice carrying the frameshift variant in the paternal or maternal allele of Magel2 were termed Magel2P:fs and Magel2M:fs, respectively. The imprinted expression and spatial distribution of truncating Magel2 transcripts in the brain were maintained. Although neonatal Magel2P:fs mice were lighter than wildtype littermates, Magel2P:fs males and females weighed the same as their wildtype littermates by eight and four weeks of age, respectively. Collectively, the overexpression mouse model may recapitulate fetal or neonatal death, which are the severest phenotypes for SYS. In contrast, the genome-edited mouse model maintains genomic imprinting and distribution of truncated Magel2 transcripts in the brain, but only partially recapitulates SYS phenotypes. Therefore, our results imply that simple gain-of-function toxic effects may not explain the patho-mechanism of SYS, but rather suggest a range of effects due to Magel2 variants as in human SYS patients.


Assuntos
Antígenos de Neoplasias/genética , Mutação/genética , Proteínas/genética , Animais , Antígenos de Neoplasias/química , Antígenos de Neoplasias/metabolismo , Peso Corporal , Encéfalo/metabolismo , Modelos Animais de Doenças , Feminino , Edição de Genes , Regulação da Expressão Gênica , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Linhagem , Fenótipo , Proteínas/química , Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
5.
Mol Cell ; 79(4): 645-659.e9, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32692974

RESUMO

Stress granules (SGs) are membrane-less ribonucleoprotein condensates that form in response to various stress stimuli via phase separation. SGs act as a protective mechanism to cope with acute stress, but persistent SGs have cytotoxic effects that are associated with several age-related diseases. Here, we demonstrate that the testis-specific protein, MAGE-B2, increases cellular stress tolerance by suppressing SG formation through translational inhibition of the key SG nucleator G3BP. MAGE-B2 reduces G3BP protein levels below the critical concentration for phase separation and suppresses SG initiation. Knockout of the MAGE-B2 mouse ortholog or overexpression of G3BP1 confers hypersensitivity of the male germline to heat stress in vivo. Thus, MAGE-B2 provides cytoprotection to maintain mammalian spermatogenesis, a highly thermosensitive process that must be preserved throughout reproductive life. These results demonstrate a mechanism that allows for tissue-specific resistance against stress and could aid in the development of male fertility therapies.


Assuntos
Grânulos Citoplasmáticos/genética , DNA Helicases/genética , Proteínas de Ligação a Poli-ADP-Ribose/genética , Biossíntese de Proteínas , RNA Helicases/genética , Proteínas com Motivo de Reconhecimento de RNA/genética , Estresse Fisiológico/genética , Regiões 5' não Traduzidas , Animais , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Grânulos Citoplasmáticos/metabolismo , Grânulos Citoplasmáticos/patologia , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , DNA Helicases/metabolismo , Feminino , Células HCT116 , Células HeLa , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Espermatogônias/citologia , Espermatogônias/patologia , Testículo/citologia , Testículo/metabolismo
6.
Immunogenetics ; 72(5): 295-304, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32577798

RESUMO

Tumor-specific neoantigens are mutated self-peptides presented by tumor cell major histocompatibility complex (MHC) molecules and are necessary to elicit host's anti-cancer cytotoxic T cell responses. It could be specifically recognized by neoantigen-specific T cell receptors (TCRs). However, current wet-lab assays for identifying peptide MHC binding are too expensive and time-consuming to meet the clinical needs. In this study, we developed an in silico method with a deep convolutional neural network (CNN) model, iConMHC, to predict peptide MHC binding affinity. Unlike other in silico methods that only learn from properties of amino acid in neoantigen peptides alone and/or MHCs alone, iConMHC learns from physical and chemical interaction properties between pairwise amino acids from the two molecules. These properties, such as contact potentials and distances in folded proteins, directly affect neoantigen-MHC binding affinity. In addition, IConMHC is a pan-allele model that is capable of making predictions for all the MHC alleles. Even for those rare MHC alleles without training data, iConMHC can make predictions with reasonable accuracy. We benchmarked iConMHC with other commonly used MHC-I binding predictors and found our model performs better than most of the pan-allele models.


Assuntos
Aprendizado Profundo , Antígenos de Histocompatibilidade Classe I/metabolismo , Peptídeos/metabolismo , Alelos , Sequência de Aminoácidos , Antígenos de Neoplasias/química , Antígenos de Neoplasias/metabolismo , Simulação por Computador , Bases de Dados de Proteínas , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Redes Neurais de Computação , Peptídeos/química , Ligação Proteica , Reprodutibilidade dos Testes
7.
Prostate ; 80(11): 872-884, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32497356

RESUMO

BACKGROUND: Castration-insensitive epithelial progenitors capable of regenerating the prostate have been proposed to be concentrated in the proximal region based on facultative assays. Functional characterization of prostate epithelial populations isolated with individual cell surface markers has failed to provide a consensus on the anatomical and transcriptional identity of proximal prostate progenitors. METHODS: Here, we use single-cell RNA sequencing to obtain a complete transcriptomic profile of all epithelial cells in the mouse prostate and urethra to objectively identify cellular subtypes. Pan-transcriptomic comparison to human prostate cell types identified a mouse equivalent of human urethral luminal cells, which highly expressed putative prostate progenitor markers. Validation of the urethral luminal cell cluster was performed using immunostaining and flow cytometry. RESULTS: Our data reveal that previously identified facultative progenitors marked by Trop2, Sca-1, KRT4, and PSCA are actually luminal epithelial cells of the urethra that extend into the proximal region of the prostate, and are resistant to castration-induced androgen deprivation. Mouse urethral luminal cells were identified to be the equivalent of previously identified human club and hillock cells that similarly extend into proximal prostate ducts. Benign prostatic hyperplasia (BPH) has long been considered an "embryonic reawakening," but the cellular origin of the hyperplastic growth concentrated in the periurethral region is unclear. We demonstrate an increase in urethral luminal cells within glandular nodules from BPH patients. Urethral luminal cells are further increased in patients treated with a 5-α reductase inhibitor. CONCLUSIONS: Our data demonstrate that cells of the proximal prostate that express putative progenitor markers, and are enriched by castration in the proximal prostate, are urethral luminal cells and that these cells may play an important role in the etiology of human BPH.


Assuntos
Próstata/citologia , Células-Tronco/citologia , Uretra/citologia , Adolescente , Adulto , Animais , Antígenos de Neoplasias/metabolismo , Moléculas de Adesão Celular/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Próstata/metabolismo , Células-Tronco/metabolismo , Uretra/metabolismo , Adulto Jovem
8.
J Cancer Res Ther ; 16(1): 105-109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32362618

RESUMO

Background: Aberrant phenotypes in acute leukemia have been reported with varying frequencies in independent studies and their association with prognostic factors is still a matter of debate. Aim: This study aims to identify the frequency of aberrant immunophenotypes in de novo acute myeloid leukemia (AML) and to evaluate their association with initial clinical and hematological features. Materials and Methods: A total of 181 patients of de novo AML were included during the time (July 2010-June 2012). The immunophenotype of all cases of AML was studied by using flow cytometry. Results: Aberrant lymphoid antigen expression was seen in 43.1% cases. Most frequent aberrant lymphoid antigen was CD7, seen in 26.5% cases. All French-American-British (FAB) subtypes except AML-M3 expressed aberrant lymphoid antigens. The expression was most common in AML-M4 in the current study. CD34 expression in AMLs was significantly associated with the expression of aberrant lymphoid antigens. Lymphoid antigen expression in adult AML was significantly associated with higher white blood cell (WBC) count (>50,000/mm3) and higher number of peripheral blasts (>70%). Conclusion: In summary, CD7 is the most common aberrant lymphoid antigen expressed in AML. FAB subtype AML-M3 is usually not associated with aberrant lymphoid antigen expression. AML cases with CD34 positivity are more likely to express aberrant lymphoid markers. The current study also supports that aberrant lymphoid antigen expression in adult AML is associated with adverse presenting hematological features (WBC count >50,000/mm3, peripheral blasts >70%). Pediatric Ly + AML cases are not associated with adverse presenting clinical and biological features.


Assuntos
Antígenos de Neoplasias/imunologia , Biomarcadores Tumorais/imunologia , Imunofenotipagem/métodos , Leucemia Mieloide Aguda/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34/imunologia , Antígenos CD34/metabolismo , Antígenos CD7/imunologia , Antígenos CD7/metabolismo , Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/metabolismo , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Prognóstico , Estudos Prospectivos , Centros de Atenção Terciária , Adulto Jovem
9.
Nat Commun ; 11(1): 1759, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32273506

RESUMO

Genomics-based neoantigen discovery can be enhanced by proteomic evidence, but there remains a lack of consensus on the performance of different quality control methods for variant peptide identification in proteogenomics. We propose to use the difference between accurately predicted and observed retention times for each peptide as a metric to evaluate different quality control methods. To this end, we develop AutoRT, a deep learning algorithm with high accuracy in retention time prediction. Analysis of three cancer data sets with a total of 287 tumor samples using different quality control strategies results in substantially different numbers of identified variant peptides and putative neoantigens. Our systematic evaluation, using the proposed retention time metric, provides insights and practical guidance on the selection of quality control strategies. We implement the recommended strategy in a computational workflow named NeoFlow to support proteogenomics-based neoantigen prioritization, enabling more sensitive discovery of putative neoantigens.


Assuntos
Antígenos de Neoplasias/metabolismo , Genômica/métodos , Neoplasias/metabolismo , Proteogenômica/métodos , Proteômica/métodos , Algoritmos , Antígenos de Neoplasias/genética , Biologia Computacional/métodos , Aprendizado Profundo , Humanos , Neoplasias/genética , Neoplasias/imunologia , Peptídeos/genética , Peptídeos/imunologia , Peptídeos/metabolismo , Proteoma/genética , Proteoma/imunologia , Proteoma/metabolismo , Espectrometria de Massas em Tandem/métodos
10.
PLoS One ; 15(4): e0230874, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32315313

RESUMO

MAGEL2 encodes the L2 member of the MAGE (melanoma antigen) protein family. Protein truncating mutations in MAGEL2 cause Schaaf-Yang syndrome, and MAGEL2 is one of a small set of genes deleted in Prader-Willi syndrome. Excessive daytime sleepiness, night-time or early morning waking, and narcoleptic symptoms are seen in people with Prader-Willi syndrome and Schaaf-Yang syndrome, while mice carrying a gene-targeted Magel2 deletion have disrupted circadian rhythms. These phenotypes suggest that MAGEL2 is important for the robustness of the circadian rhythm. However, a cellular role for MAGEL2 has yet to be elucidated. MAGEL2 influences the ubiquitination of substrate proteins to target them for further modification or to alter their stability through proteasomal degradation pathways. Here, we characterized relationships among MAGEL2 and proteins that regulate circadian rhythm. The effect of MAGEL2 on the key circadian rhythm protein cryptochrome 1 (CRY1) was assessed using in vivo proximity labelling (BioID), immunofluorescence microscopy and ubiquitination assays. We demonstrate that MAGEL2 modulates the ubiquitination of CRY1. Further studies will clarify the cellular role MAGEL2 normally plays in circadian rhythm, in part through ubiquitination and regulation of stability of the CRY1 protein.


Assuntos
Antígenos de Neoplasias/metabolismo , Ritmo Circadiano , Criptocromos/metabolismo , Enzimas Desubiquitinantes/metabolismo , Proteínas/metabolismo , Ubiquitinação , Animais , Camundongos , Peptidase 7 Específica de Ubiquitina/metabolismo
11.
J Leukoc Biol ; 107(4): 625-633, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32170883

RESUMO

The goal of precision immunotherapy is to direct a patient's T cell response against the immunogenic mutations expressed on their tumors. Most immunotherapy approaches to-date have focused on MHC class I-restricted peptide epitopes by which cytotoxic CD8+ T lymphocytes (CTL) can directly recognize tumor cells. This strategy largely overlooks the critical role of MHC class II-restricted CD4+ T cells as both positive regulators of CTL and other effector cell types, and as direct effectors of antitumor immunity. In this review, we will discuss the role of neoantigen specific CD4+ T cells in cancer immunotherapy and how existing treatment modalities may be leveraged to engage this important T cell subset.


Assuntos
Antígenos de Neoplasias/metabolismo , Imunoterapia , Neoplasias/imunologia , Neoplasias/terapia , Animais , Linfócitos T CD4-Positivos/imunologia , Vacinas Anticâncer/imunologia , Humanos , Linfócitos T Auxiliares-Indutores/imunologia
12.
Zhonghua Gan Zang Bing Za Zhi ; 28(2): 147-151, 2020 Feb 20.
Artigo em Chinês | MEDLINE | ID: mdl-32164066

RESUMO

Objective: To investigate the effect of knockdown of O-GlcNAc transferase (OGT) on hepatocyte fat synthesis. Methods: Liver cell line L02 were used to established the model of hepatic steatosis. The levels of OGT and O-GlcNAc protein were detected by Western blot. The OGT knockdown cell line of L02 cells was established, and its lipid formation ability was detected after induction of oleic acid (OA). Real-time quantitative PCR (qRT-PCR) and Western blot were used to detect mRNA and protein expression of enzymes related to fat synthesis. An independent sample t test was used. Results: Western blot showed that the expression of OGT and O-GlcNAc was increased in L02 cells after adipogenesis (P < 0.05). After shOGT lentivirus infects L02 cells, OGT mRNA levels were down-regulated (P < 0.01). Oil red O staining showed that the lipid in L02 shOGT cells decreased, qRT-PCR showed that the mRNA expressions of fat synthase (ACC1), (FASN) and (SCD1) were decreased, the difference was statistically significant (P < 0.05), protein Expression is consistent with mRNA expression. Conclusion: Knockdown of OGT can inhibit hepatocyte fat synthesis by reducing O-GlcNAc levels.


Assuntos
Antígenos de Neoplasias/metabolismo , Fígado Gorduroso , Hepatócitos/metabolismo , Histona Acetiltransferases/metabolismo , Hialuronoglucosaminidase/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Linhagem Celular , Humanos
13.
Life Sci ; 250: 117543, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32169518

RESUMO

AIMS: HMGB1 has been reported to play a crucial role in the physiological and pathophysiological responses during pregnancy. However, it is still unknown whether excessively expressed HMGB1 at the maternal-fetal interface related to Unexplained Recurrent Spontaneous Abortion (URSA). This study was designed to investigate the local capability of HMGB1 in the pathology of URSA, determined the distributions and characteristics of HMGB1, its receptors (RAGE/TLR2/TLR4) and important signaling molecule NF-κB p65 expression at the maternal-fetal interface,as well as compared the differences of HMGB1 expression between the URSA group, control group and aspirin treatment group. MATERIAL AND METHODS: H&E staining, Western blot analysis, immunofluorescence assay and immunohistochemical staining were applied to determine the effect of HMGB1 and its receptors at the maternal-fetal interface. ELISA was utilized to detect the concentration of HMGB1 in plasma. KEY FINDINGS: Our study demonstrated that the activation of the HMGB1-RAGE/TLR2/TLR4-NF-κB pathway at the maternal-fetal interface may have occurred in the URSA group. HMGB1 concentration in plasma was higher in the URSA group than the control group. Furthermore, the levels of HMGB1 of subjects with URSA could be reduced by administrating low doses of aspirin (ASPL). SIGNIFICANCE: This is the first report indicating the roles of HMGB1 at the maternal-fetal interface of URSA patients and broadening the horizons for clinical treatment of URSA. HMGB1-RAGE/TLR2/TLR4-NF-κB signaling pathway may be activated at the maternal-fetal interface in URSA and account for its pathogenesis. HMGB1 have the potential to be promising biomarkers in prevention and therapy of URSA.


Assuntos
Aborto Habitual/metabolismo , Aborto Espontâneo/metabolismo , Proteína HMGB1/metabolismo , Transdução de Sinais , Antígenos de Neoplasias/metabolismo , Aspirina/administração & dosagem , Feminino , Feto , Regulação da Expressão Gênica , Humanos , Antígenos Comuns de Leucócito/metabolismo , Troca Materno-Fetal , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Gravidez , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Fator de Transcrição RelA/metabolismo , Regulação para Cima
14.
Nat Commun ; 11(1): 1395, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170083

RESUMO

Oncolytic viruses offer an in situ vaccination approach to activate tumor-specific T cell responses. However, the upregulation of PD-L1 expression on tumor cells and immune cells leads to tumor resistance to oncolytic immunotherapy. In this study, we generate an engineered oncolytic virus that coexpresses a PD-L1 inhibitor and GM-CSF. We find that the oncolytic virus is able to secrete the PD-L1 inhibitor that systemically binds and inhibits PD-L1 on tumor cells and immune cells. Importantly, the intratumoral injection with the oncolytic virus overcomes PD-L1-mediated immunosuppression during both the priming and effector phases, provokes systemic T cell responses against dominant and subdominant neoantigen epitopes derived from mutations, and leads to an effective rejection of both virus-injected and distant tumors. In summary, this engineered oncolytic virus is able to activate tumor neoantigen-specific T cell responses, providing a potent, individual tumor-specific oncolytic immunotherapy for cancer patients, especially those resistant to PD-1/PD-L1 blockade therapy.


Assuntos
Antígeno B7-H1/antagonistas & inibidores , Terapia Viral Oncolítica , Vírus Oncolíticos/genética , Vírus Oncolíticos/metabolismo , Animais , Antígenos de Neoplasias/metabolismo , Antineoplásicos , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Engenharia Genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Células HEK293 , Humanos , Imunossupressão , Imunoterapia , Camundongos , Camundongos Endogâmicos C57BL , Vírus Oncolíticos/imunologia , Proteínas Recombinantes
15.
Mol Immunol ; 121: 99-110, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32199212

RESUMO

The complement cascade consists of cell bound and serum proteins acting together to protect the host from pathogens, remove cancerous cells and effectively links innate and adaptive immune responses. Despite its usefulness in microbial neutralization and clearance of cancerous cells, excessive complement activation causes an immune imbalance and tissue damage in the host. Hence, a series of complement regulatory proteins present at a higher concentration in blood plasma and on cell surfaces tightly regulate the cascade. The complement cascade can be initiated by B-1 B cell production of natural antibodies. Natural antibodies arise spontaneously without any known exogenous antigenic or microbial stimulus and protect against invading pathogens, clear apoptotic cells, provide tissue homeostasis, and modulate adaptive immune functions. Natural IgM antibodies recognize microbial and cancer antigens and serve as an activator of complement mediated lysis. This review will discuss advances in complement activation and regulation in bacterial and viral infections, and cancer. We will also explore the crosstalk of natural antibodies with bacterial populations and cancer.


Assuntos
Infecções Bacterianas/imunologia , Imunidade Humoral , Imunidade Inata , Neoplasias/imunologia , Viroses/imunologia , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/metabolismo , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Antígenos Virais/imunologia , Antígenos Virais/metabolismo , Apoptose/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Ativação do Complemento , Proteínas do Sistema Complemento/imunologia , Proteínas do Sistema Complemento/metabolismo , Humanos , Imunoglobulina M/imunologia , Imunoglobulina M/metabolismo , Receptores de Complemento/imunologia , Receptores de Complemento/metabolismo , Evasão Tumoral
16.
Nat Commun ; 11(1): 1335, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-32165639

RESUMO

Immune checkpoint blockade (ICB)-based or natural cancer immune responses largely eliminate tumours. Yet, they require additional mechanisms to arrest those cancer cells that are not rejected. Cytokine-induced senescence (CIS) can stably arrest cancer cells, suggesting that interferon-dependent induction of senescence-inducing cell cycle regulators is needed to control those cancer cells that escape from killing. Here we report in two different cancers sensitive to T cell-mediated rejection, that deletion of the senescence-inducing cell cycle regulators p16Ink4a/p19Arf (Cdkn2a) or p21Cip1 (Cdkn1a) in the tumour cells abrogates both the natural and the ICB-induced cancer immune control. Also in humans, melanoma metastases that progressed rapidly during ICB have losses of senescence-inducing genes and amplifications of senescence inhibitors. Metastatic cells also resist CIS. Such genetic and functional alterations are infrequent in metastatic melanomas regressing during ICB. Thus, activation of tumour-intrinsic, senescence-inducing cell cycle regulators is required to stably arrest cancer cells that escape from eradication.


Assuntos
Ciclo Celular , Senescência Celular , Interferons/metabolismo , Melanoma/imunologia , Melanoma/patologia , Animais , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Linhagem Celular Tumoral , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Humanos , Imunoterapia , Antígeno Ki-67/metabolismo , Linfonodos/patologia , Melanoma/terapia , Melanoma/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Transcrição STAT1/metabolismo , Análise de Sobrevida , Carga Tumoral
17.
Pediatr Blood Cancer ; 67(5): e28231, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32124536

RESUMO

BACKGROUND: Proliferation of large granular lymphocytes (LGL) and T-cell LGL (T-LGL) in peripheral blood along with demonstration of clonality are the hallmarks of a heterogeneous group of disorders, including T-LGL leukemia or T-LGL lymphocytosis. They are often associated with neutropenia and responsive to immunosuppression. The true nature of this entity is not well understood. Some cases are reported as reactive phenomena with very limited experience in pediatric population. METHODS: Hematology/Oncology Flow Cytometry Laboratory database has been reviewed retrospectively. Patients with identifiable distinct CD5-dim T-cell population and positive clonal T-cell receptor rearrangement were included in the analysis. Clinical and laboratory data were then reviewed. RESULTS: Sixteen cases of children and young adults with increased peripheral blood clonal T-LGL population characterized by dim CD5 expression with wide range of underlying immune dysregulation/stimulation disorders were reviewed. Extended follow up with repeat testing suggested the reactive nature of persistent clonal T-LGL proliferations in this group. CONCLUSIONS: Our observations indicate that clonal T-LGL proliferations in children and young adults are reactive in nature and some can be persistent with an indolent course with unknown consequentiality. Clonal T-LGL cells could be targeting the most prominent immunogenic stressor(s) involved as a control mechanism.


Assuntos
Antígenos de Neoplasias/metabolismo , Antígenos CD5/metabolismo , Proliferação de Células , Leucemia Linfocítica Granular Grande , Linfócitos T , Adolescente , Adulto , Criança , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Lactente , Leucemia Linfocítica Granular Grande/metabolismo , Leucemia Linfocítica Granular Grande/patologia , Masculino , Estudos Retrospectivos , Linfócitos T/metabolismo , Linfócitos T/patologia
18.
Nat Commun ; 11(1): 951, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075964

RESUMO

Neoantigen burden is regarded as a fundamental determinant of response to immunotherapy. However, its predictive value remains in question because some tumours with high neoantigen load show resistance. Here, we investigate our patient cohort together with a public cohort by our algorithms for the modelling of peptide-MHC binding and inter-cohort genomic prediction of therapeutic resistance. We first attempt to predict MHC-binding peptides at high accuracy with convolutional neural networks. Our prediction outperforms previous methods in > 70% of test cases. We then develop a classifier that can predict resistance from functional mutations. The predictive genes are involved in immune response and EGFR signalling, whereas their mutation patterns reflect positive selection. When integrated with our neoantigen profiling, these anti-immunogenic mutations reveal higher predictive power than known resistance factors. Our results suggest that the clinical benefit of immunotherapy can be determined by neoantigens that induce immunity and functional mutations that facilitate immune evasion.


Assuntos
Algoritmos , Antígenos de Neoplasias/genética , Neoplasias/imunologia , Neoplasias/terapia , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Estudos de Coortes , Receptores ErbB/genética , Receptores ErbB/imunologia , Genoma Humano/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Evasão da Resposta Imune/genética , Evasão da Resposta Imune/imunologia , Imunoterapia , Mutação , Neoplasias/genética , Neoplasias/patologia , Redes Neurais de Computação , Fragmentos de Peptídeos/metabolismo , Ligação Proteica
19.
J Med Chem ; 63(5): 2470-2488, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-31972093

RESUMO

Two series of saccharin/isoxazole and saccharin/isoxazoline hybrids were synthesized by 1,3-dipolar cycloaddition. The new compounds showed to be endowed with potent and selective inhibitory activity against the cancer-related human carbonic anhydrase (hCA) IX and XII isoforms in the nanomolar range, while no affinity was encountered for off-targets, such as hCA I and II. Successive enantioseparation on a milligram scale of the most representative compounds led to the discovery that (S)-isomers were more potent than their corresponding (R)-enantiomers. Lastly, molecular modeling studies were conducted to define those structural requirements that were responsible for the discrimination among selected human isoforms of carbonic anhydrases. Two nanomolar hCA IX and XII inhibitors were also screened for their selective toxicity against non tumoral primary cells (fibroblasts) and against a breast adenocarcinoma cell line (MCF7) in hypoxic environment. The efficacious combination of these compounds with doxorubicin on MCF7 cells was demonstrated after 72 h of treatment.


Assuntos
Antígenos de Neoplasias/metabolismo , Anidrase Carbônica IX/metabolismo , Inibidores da Anidrase Carbônica/química , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Sacarina/química , Sacarina/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Anidrase Carbônica IX/antagonistas & inibidores , Inibidores da Anidrase Carbônica/síntese química , Linhagem Celular , Reação de Cicloadição , Humanos , Isoxazóis/síntese química , Isoxazóis/química , Isoxazóis/farmacologia , Células MCF-7 , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Neoplasias/metabolismo , Sacarina/síntese química
20.
J Enzyme Inhib Med Chem ; 35(1): 549-554, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31967484

RESUMO

A small series of 2,4-dioxothiazolidinyl acetic acids was prepared from thiourea, chloroacetic acid, aromatic aldehydes, and ethyl-2-bromoacetate. They were assayed for the inhibition of four physiologically relevant carbonic anhydrase (CA, EC 4.2.1.1) isoforms of human (h) origin, the cytosolic hCA I and II, and the transmembrane hCA IX and XII, involved among others in tumorigenesis (hCA IX and XII) and glaucoma (hCA II and XII). The two cytosolic isoforms were not inhibited by these carboxylates, which were also rather ineffective as hCA IX inhibitors. On the other hand, they showed submicromolar hCA XII inhibition, with KIs in the range of 0.30-0.93 µM, making them highly CA XII-selective inhibitors.


Assuntos
Acetatos/farmacologia , Anidrase Carbônica IX/antagonistas & inibidores , Inibidores da Anidrase Carbônica/classificação , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Tiazóis/farmacologia , Acetatos/síntese química , Acetatos/química , Antígenos de Neoplasias/metabolismo , Anidrase Carbônica IX/metabolismo , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química
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