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1.
Cell ; 184(15): 3949-3961.e11, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34161776

RESUMO

Monoclonal antibodies against SARS-CoV-2 are a clinically validated therapeutic option against COVID-19. Because rapidly emerging virus mutants are becoming the next major concern in the fight against the global pandemic, it is imperative that these therapeutic treatments provide coverage against circulating variants and do not contribute to development of treatment-induced emergent resistance. To this end, we investigated the sequence diversity of the spike protein and monitored emergence of virus variants in SARS-COV-2 isolates found in COVID-19 patients treated with the two-antibody combination REGEN-COV, as well as in preclinical in vitro studies using single, dual, or triple antibody combinations, and in hamster in vivo studies using REGEN-COV or single monoclonal antibody treatments. Our study demonstrates that the combination of non-competing antibodies in REGEN-COV provides protection against all current SARS-CoV-2 variants of concern/interest and also protects against emergence of new variants and their potential seeding into the population in a clinical setting.


Assuntos
Anticorpos Monoclonais/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Mutação/genética , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Animais , COVID-19/virologia , Chlorocebus aethiops , Cricetinae , Microscopia Crioeletrônica , Hospitalização , Humanos , Pulmão/patologia , Pulmão/virologia , Masculino , Testes de Neutralização , Células Vero , Carga Viral
2.
Cell ; 159(3): 691-6, 2014 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-25417115

RESUMO

Recently, it was reported that angiopoietin-like protein 8 (ANGPTL8) was the long-sought "betatrophin" that could control pancreatic beta cell proliferation. However, studies of Angptl8(?/?) mice revealed profound reduction of triglyceride levels, but no abnormalities in glucose homeostasis. We now report that Angptl8(?/?) mice undergo entirely normal beta cell expansion in response to insulin resistance resulting from either a high-fat diet or from the administration of the insulin receptor antagonist S961. Furthermore, overexpression of ANGPTL8 in livers of mice doubles plasma triglyceride levels, but does not alter beta cell expansion nor glucose metabolism. These data indicate that ANGPTL8 does not play a role in controlling beta cell growth, nor can it be given to induce such expansion. The findings that plasma triglyceride levels are reduced by Angptl8 deletion and increased following ANGPTL8 overexpression support the possibility that inhibition of ANGPTL8 represents a therapeutic strategy for hypertriglyceridemia.


Assuntos
Angiopoietinas/metabolismo , Células Secretoras de Insulina/citologia , Proteína 8 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina , Angiopoietinas/genética , Animais , Dieta Hiperlipídica , Resistência à Insulina , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Triglicerídeos/metabolismo
3.
Nature ; 611(7937): 733-743, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36289335

RESUMO

Colorectal malignancies are a leading cause of cancer-related death1 and have undergone extensive genomic study2,3. However, DNA mutations alone do not fully explain malignant transformation4-7. Here we investigate the co-evolution of the genome and epigenome of colorectal tumours at single-clone resolution using spatial multi-omic profiling of individual glands. We collected 1,370 samples from 30 primary cancers and 8 concomitant adenomas and generated 1,207 chromatin accessibility profiles, 527 whole genomes and 297 whole transcriptomes. We found positive selection for DNA mutations in chromatin modifier genes and recurrent somatic chromatin accessibility alterations, including in regulatory regions of cancer driver genes that were otherwise devoid of genetic mutations. Genome-wide alterations in accessibility for transcription factor binding involved CTCF, downregulation of interferon and increased accessibility for SOX and HOX transcription factor families, suggesting the involvement of developmental genes during tumourigenesis. Somatic chromatin accessibility alterations were heritable and distinguished adenomas from cancers. Mutational signature analysis showed that the epigenome in turn influences the accumulation of DNA mutations. This study provides a map of genetic and epigenetic tumour heterogeneity, with fundamental implications for understanding colorectal cancer biology.


Assuntos
Neoplasias Colorretais , Epigenoma , Genoma Humano , Mutação , Humanos , Adenoma/genética , Adenoma/patologia , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Cromatina/genética , Cromatina/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Epigenoma/genética , Oncogenes/genética , Fatores de Transcrição/metabolismo , Genoma Humano/genética , Interferons
4.
Nature ; 611(7937): 744-753, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36289336

RESUMO

Genetic and epigenetic variation, together with transcriptional plasticity, contribute to intratumour heterogeneity1. The interplay of these biological processes and their respective contributions to tumour evolution remain unknown. Here we show that intratumour genetic ancestry only infrequently affects gene expression traits and subclonal evolution in colorectal cancer (CRC). Using spatially resolved paired whole-genome and transcriptome sequencing, we find that the majority of intratumour variation in gene expression is not strongly heritable but rather 'plastic'. Somatic expression quantitative trait loci analysis identified a number of putative genetic controls of expression by cis-acting coding and non-coding mutations, the majority of which were clonal within a tumour, alongside frequent structural alterations. Consistently, computational inference on the spatial patterning of tumour phylogenies finds that a considerable proportion of CRCs did not show evidence of subclonal selection, with only a subset of putative genetic drivers associated with subclone expansions. Spatial intermixing of clones is common, with some tumours growing exponentially and others only at the periphery. Together, our data suggest that most genetic intratumour variation in CRC has no major phenotypic consequence and that transcriptional plasticity is, instead, widespread within a tumour.


Assuntos
Adaptação Fisiológica , Neoplasias Colorretais , Regulação Neoplásica da Expressão Gênica , Fenótipo , Humanos , Adaptação Fisiológica/genética , Células Clonais/metabolismo , Células Clonais/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Mutação , Sequenciamento do Exoma , Transcrição Gênica
5.
N Engl J Med ; 390(24): 2239-2251, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38924731

RESUMO

BACKGROUND: Dupilumab is a human monoclonal antibody that blocks interleukin-4 and interleukin-13 pathways and has shown efficacy in five different atopic diseases marked by type 2 inflammation, including eosinophilic esophagitis in adults and adolescents. METHODS: In this phase 3 trial, we randomly assigned, in a 2:2:1:1 ratio, patients 1 to 11 years of age with active eosinophilic esophagitis who had had no response to proton-pump inhibitors to 16 weeks of a higher-exposure or lower-exposure subcutaneous dupilumab regimen or to placebo (two groups) (Part A). At the end of Part A, eligible patients in each dupilumab group continued the same regimen and those in the placebo groups were assigned to higher-exposure or lower-exposure dupilumab for 36 weeks (Part B). At each level of exposure, dupilumab was administered in one of four doses tiered according to baseline body weight. The primary end point was histologic remission (peak esophageal intraepithelial eosinophil count, ≤6 per high-power field) at week 16. Key secondary end points were tested hierarchically. RESULTS: In Part A, histologic remission occurred in 25 of the 37 patients (68%) in the higher-exposure group, in 18 of the 31 patients (58%) in the lower-exposure group, and in 1 of the 34 patients (3%) in the placebo group (difference between the higher-exposure regimen and placebo, 65 percentage points [95% confidence interval {CI}, 48 to 81; P<0.001]; difference between the lower-exposure regimen and placebo, 55 percentage points [95% CI, 37 to 73; P<0.001]). The higher-exposure dupilumab regimen led to significant improvements in histologic, endoscopic, and transcriptomic measures as compared with placebo. The improvements in histologic, endoscopic, and transcriptomic measures between baseline and week 52 in all the patients were generally similar to the improvements between baseline and week 16 in the patients who received dupilumab in Part A. In Part A, the incidence of coronavirus disease 2019, nausea, injection-site pain, and headache was at least 10 percentage points higher among the patients who received dupilumab (at either dose) than among those who received placebo. Serious adverse events were reported in 3 patients who received dupilumab during Part A and in 6 patients overall during Part B. CONCLUSIONS: Dupilumab resulted in histologic remission in a significantly higher percentage of children with eosinophilic esophagitis than placebo. The higher-exposure dupilumab regimen also led to improvements in measures of key secondary end points as compared with placebo. (Funded by Sanofi and Regeneron Pharmaceuticals; EoE KIDS ClinicalTrials.gov number, NCT04394351.).


Assuntos
Anticorpos Monoclonais Humanizados , Esofagite Eosinofílica , Humanos , Esofagite Eosinofílica/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Masculino , Feminino , Criança , Método Duplo-Cego , Pré-Escolar , Lactente , Eosinófilos/efeitos dos fármacos , Injeções Subcutâneas , Relação Dose-Resposta a Droga , Esôfago/patologia , Interleucina-13/antagonistas & inibidores , Indução de Remissão , Interleucina-4/antagonistas & inibidores
6.
N Engl J Med ; 390(24): 2274-2283, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38767614

RESUMO

BACKGROUND: Dupilumab, a fully human monoclonal antibody that blocks the shared receptor component for interleukin-4 and interleukin-13, key and central drivers of type 2 inflammation, has shown efficacy and safety in a phase 3 trial involving patients with chronic obstructive pulmonary disease (COPD) and type 2 inflammation and an elevated risk of exacerbation. Whether the findings would be confirmed in a second phase 3 trial was unclear. METHODS: In a phase 3, double-blind, randomized trial, we assigned patients with COPD who had a blood eosinophil count of 300 cells per microliter or higher to receive subcutaneous dupilumab (300 mg) or placebo every 2 weeks. The primary end point was the annualized rate of moderate or severe exacerbations. Key secondary end points, analyzed in a hierarchical manner to adjust for multiplicity, included the changes from baseline in the prebronchodilator forced expiratory volume in 1 second (FEV1) at weeks 12 and 52 and in the St. George's Respiratory Questionnaire (SGRQ; scores range from 0 to 100, with lower scores indicating better quality of life) total score at week 52. RESULTS: A total of 935 patients underwent randomization: 470 were assigned to the dupilumab group and 465 to the placebo group. As prespecified, the primary analysis was performed after a positive interim analysis and included all available data for the 935 participants, 721 of whom were included in the analysis at week 52. The annualized rate of moderate or severe exacerbations was 0.86 (95% confidence interval [CI], 0.70 to 1.06) with dupilumab and 1.30 (95% CI, 1.05 to 1.60) with placebo; the rate ratio as compared with placebo was 0.66 (95% CI, 0.54 to 0.82; P<0.001). The prebronchodilator FEV1 increased from baseline to week 12 with dupilumab (least-squares mean change, 139 ml [95% CI, 105 to 173]) as compared with placebo (least-squares mean change, 57 ml [95% CI, 23 to 91]), with a significant least-squares mean difference at week 12 of 82 ml (P<0.001) and at week 52 of 62 ml (P = 0.02). No significant between-group difference was observed in the change in SGRQ scores from baseline to 52 weeks. The incidence of adverse events was similar in the two groups and consistent with the established profile of dupilumab. CONCLUSIONS: In patients with COPD and type 2 inflammation as indicated by elevated blood eosinophil counts, dupilumab was associated with fewer exacerbations and better lung function than placebo. (Funded by Sanofi and Regeneron Pharmaceuticals; NOTUS ClinicalTrials.gov number, NCT04456673.).


Assuntos
Anticorpos Monoclonais Humanizados , Eosinófilos , Doença Pulmonar Obstrutiva Crônica , Humanos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Método Duplo-Cego , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Contagem de Leucócitos , Volume Expiratório Forçado/efeitos dos fármacos , Qualidade de Vida , Injeções Subcutâneas , Inflamação/tratamento farmacológico , Inflamação/sangue
7.
N Engl J Med ; 389(3): 205-214, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37272521

RESUMO

BACKGROUND: In some patients with chronic obstructive pulmonary disease (COPD), type 2 inflammation may increase exacerbation risk and may be indicated by elevated blood eosinophil counts. Dupilumab, a fully human monoclonal antibody, blocks the shared receptor component for interleukin-4 and interleukin-13, key drivers of type 2 inflammation. METHODS: In a phase 3, double-blind, randomized trial, we assigned patients with COPD who had a blood eosinophil count of at least 300 per microliter and an elevated exacerbation risk despite the use of standard triple therapy to receive dupilumab (300 mg) or placebo subcutaneously once every 2 weeks. The primary end point was the annualized rate of moderate or severe exacerbations of COPD. Key secondary and other end points that were corrected for multiplicity were the change in the prebronchodilator forced expiratory volume in 1 second (FEV1) and in the scores on the St. George's Respiratory Questionnaire (SGRQ; range, 0 to 100, with lower scores indicating a better quality of life) and the Evaluating Respiratory Symptoms in COPD (E-RS-COPD; range, 0 to 40, with lower scores indicating less severe symptoms). RESULTS: A total of 939 patients underwent randomization: 468 to the dupilumab group and 471 to the placebo group. The annualized rate of moderate or severe exacerbations was 0.78 (95% confidence interval [CI], 0.64 to 0.93) with dupilumab and 1.10 (95% CI, 0.93 to 1.30) with placebo (rate ratio, 0.70; 95% CI, 0.58 to 0.86; P<0.001). The prebronchodilator FEV1 increased from baseline to week 12 by a least-squares (LS) mean of 160 ml (95% CI, 126 to 195) with dupilumab and 77 ml (95% CI, 42 to 112) with placebo (LS mean difference, 83 ml; 95% CI, 42 to 125; P<0.001), a difference that was sustained through week 52. At week 52, the SGRQ score had improved by an LS mean of -9.7 (95% CI, -11.3 to -8.1) with dupilumab and -6.4 (95% CI, -8.0 to -4.8) with placebo (LS mean difference, -3.4; 95% CI, -5.5 to -1.3; P = 0.002). The E-RS-COPD score at week 52 had improved by an LS mean of -2.7 (95% CI, -3.2 to -2.2) with dupilumab and -1.6 (95% CI, -2.1 to -1.1) with placebo (LS mean difference, -1.1; 95% CI, -1.8 to -0.4; P = 0.001). The numbers of patients with adverse events that led to discontinuation of dupilumab or placebo, serious adverse events, and adverse events that led to death were balanced in the two groups. CONCLUSIONS: Among patients with COPD who had type 2 inflammation as indicated by elevated blood eosinophil counts, those who received dupilumab had fewer exacerbations, better lung function and quality of life, and less severe respiratory symptoms than those who received placebo. (Funded by Sanofi and Regeneron Pharmaceuticals; BOREAS ClinicalTrials.gov number, NCT03930732.).


Assuntos
Anticorpos Monoclonais Humanizados , Eosinófilos , Doença Pulmonar Obstrutiva Crônica , Humanos , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Método Duplo-Cego , Eosinófilos/imunologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/imunologia , Qualidade de Vida , Inflamação/classificação , Inflamação/imunologia
8.
N Engl J Med ; 389(14): 1263-1272, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37792612

RESUMO

BACKGROUND: More than half of patients with polymyalgia rheumatica have a relapse during tapering of glucocorticoid therapy. Previous studies have suggested that interleukin-6 blockade may be clinically useful in the treatment of polymyalgia rheumatica. Sarilumab, a human monoclonal antibody, binds interleukin-6 receptor α and efficiently blocks the interleukin-6 pathway. METHODS: In this phase 3 trial, we randomly assigned patients in a 1:1 ratio to receive 52 weeks of a twice-monthly subcutaneous injection of either sarilumab (at a dose of 200 mg) plus a 14-week prednisone taper or placebo plus a 52-week prednisone taper. The primary outcome at 52 weeks was sustained remission, which was defined as the resolution of signs and symptoms of polymyalgia rheumatica by week 12 and sustained normalization of the C-reactive protein level, absence of disease flare, and adherence to the prednisone taper from weeks 12 through 52. RESULTS: A total of 118 patients underwent randomization (60 to receive sarilumab and 58 to receive placebo). At week 52, sustained remission occurred in 28% (17 of 60 patients) in the sarilumab group and in 10% (6 of 58 patients) in the placebo group (difference, 18 percentage points; 95% confidence interval, 4 to 32; P = 0.02). The median cumulative glucocorticoid dose at 52 weeks was significantly lower in the sarilumab group than in the placebo group (777 mg vs. 2044 mg; P<0.001). The most common adverse events with sarilumab as compared with placebo were neutropenia (15% vs. 0%), arthralgia (15% vs. 5%), and diarrhea (12% vs. 2%). More treatment-related discontinuations were observed in the sarilumab group than in the placebo group (12% vs. 7%). CONCLUSIONS: Sarilumab showed significant efficacy in achieving sustained remission and reducing the cumulative glucocorticoid dose in patients with a relapse of polymyalgia rheumatica during glucocorticoid tapering. (Funded by Sanofi and Regeneron Pharmaceuticals; SAPHYR ClinicalTrials.gov number, NCT03600818.).


Assuntos
Anticorpos Monoclonais Humanizados , Redução da Medicação , Polimialgia Reumática , Humanos , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Interleucina-6/antagonistas & inibidores , Polimialgia Reumática/tratamento farmacológico , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Recidiva , Resultado do Tratamento , Anticorpos Monoclonais Humanizados/uso terapêutico , Redução da Medicação/métodos , Proteína C-Reativa/análise
9.
Immunity ; 46(2): 197-204, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28228279

RESUMO

Response to immune checkpoint blockade in mesenchymal tumors is poorly characterized, but immunogenomic dissection of these cancers could inform immunotherapy mediators. We identified a treatment-naive patient who has metastatic uterine leiomyosarcoma and has experienced complete tumor remission for >2 years on anti-PD-1 (pembrolizumab) monotherapy. We analyzed the primary tumor, the sole treatment-resistant metastasis, and germline tissue to explore mechanisms of immunotherapy sensitivity and resistance. Both tumors stained diffusely for PD-L2 and showed sparse PD-L1 staining. PD-1+ cell infiltration significantly decreased in the resistant tumor (p = 0.039). Genomically, the treatment-resistant tumor uniquely harbored biallelic PTEN loss and had reduced expression of two neoantigens that demonstrated strong immunoreactivity with patient T cells in vitro, suggesting long-lasting immunological memory. In this near-complete response to PD-1 blockade in a mesenchymal tumor, we identified PTEN mutations and reduced expression of genes encoding neoantigens as potential mediators of resistance to immune checkpoint therapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Leiomiossarcoma/patologia , PTEN Fosfo-Hidrolase/genética , Neoplasias Uterinas/patologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Análise Mutacional de DNA , Feminino , Perfilação da Expressão Gênica , Humanos , Leiomiossarcoma/tratamento farmacológico , Leiomiossarcoma/genética , Pessoa de Meia-Idade , Mutação , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Transcriptoma , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/genética
10.
Nature ; 586(7831): 749-756, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33087929

RESUMO

The UK Biobank is a prospective study of 502,543 individuals, combining extensive phenotypic and genotypic data with streamlined access for researchers around the world1. Here we describe the release of exome-sequence data for the first 49,960 study participants, revealing approximately 4 million coding variants (of which around 98.6% have a frequency of less than 1%). The data include 198,269 autosomal predicted loss-of-function (LOF) variants, a more than 14-fold increase compared to the imputed sequence. Nearly all genes (more than 97%) had at least one carrier with a LOF variant, and most genes (more than 69%) had at least ten carriers with a LOF variant. We illustrate the power of characterizing LOF variants in this population through association analyses across 1,730 phenotypes. In addition to replicating established associations, we found novel LOF variants with large effects on disease traits, including PIEZO1 on varicose veins, COL6A1 on corneal resistance, MEPE on bone density, and IQGAP2 and GMPR on blood cell traits. We further demonstrate the value of exome sequencing by surveying the prevalence of pathogenic variants of clinical importance, and show that 2% of this population has a medically actionable variant. Furthermore, we characterize the penetrance of cancer in carriers of pathogenic BRCA1 and BRCA2 variants. Exome sequences from the first 49,960 participants highlight the promise of genome sequencing in large population-based studies and are now accessible to the scientific community.


Assuntos
Bases de Dados Genéticas , Sequenciamento do Exoma , Exoma/genética , Mutação com Perda de Função/genética , Fenótipo , Idoso , Densidade Óssea/genética , Colágeno Tipo VI/genética , Demografia , Feminino , Genes BRCA1 , Genes BRCA2 , Genótipo , Humanos , Canais Iônicos/genética , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Penetrância , Fragmentos de Peptídeos/genética , Reino Unido , Varizes/genética , Proteínas Ativadoras de ras GTPase/genética
11.
Nature ; 587(7832): 126-132, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32879494

RESUMO

Chromosomal instability in cancer consists of dynamic changes to the number and structure of chromosomes1,2. The resulting diversity in somatic copy number alterations (SCNAs) may provide the variation necessary for tumour evolution1,3,4. Here we use multi-sample phasing and SCNA analysis of 1,421 samples from 394 tumours across 22 tumour types to show that continuous chromosomal instability results in pervasive SCNA heterogeneity. Parallel evolutionary events, which cause disruption in the same genes (such as BCL9, MCL1, ARNT (also known as HIF1B), TERT and MYC) within separate subclones, were present in 37% of tumours. Most recurrent losses probably occurred before whole-genome doubling, that was found as a clonal event in 49% of tumours. However, loss of heterozygosity at the human leukocyte antigen (HLA) locus and loss of chromosome 8p to a single haploid copy recurred at substantial subclonal frequencies, even in tumours with whole-genome doubling, indicating ongoing karyotype remodelling. Focal amplifications that affected chromosomes 1q21 (which encompasses BCL9, MCL1 and ARNT), 5p15.33 (TERT), 11q13.3 (CCND1), 19q12 (CCNE1) and 8q24.1 (MYC) were frequently subclonal yet appeared to be clonal within single samples. Analysis of an independent series of 1,024 metastatic samples revealed that 13 focal SCNAs were enriched in metastatic samples, including gains in chromosome 8q24.1 (encompassing MYC) in clear cell renal cell carcinoma and chromosome 11q13.3 (encompassing CCND1) in HER2+ breast cancer. Chromosomal instability may enable the continuous selection of SCNAs, which are established as ordered events that often occur in parallel, throughout tumour evolution.


Assuntos
Instabilidade Cromossômica/genética , Evolução Molecular , Cariótipo , Metástase Neoplásica/genética , Neoplasias/genética , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 8/genética , Células Clonais/metabolismo , Células Clonais/patologia , Ciclina E/genética , Variações do Número de Cópias de DNA/genética , Feminino , Humanos , Perda de Heterozigosidade/genética , Masculino , Mutagênese , Metástase Neoplásica/patologia , Neoplasias/patologia , Proteínas Oncogênicas/genética
12.
Proc Natl Acad Sci U S A ; 120(41): e2307149120, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37748080

RESUMO

The search for definitive biosignatures-unambiguous markers of past or present life-is a central goal of paleobiology and astrobiology. We used pyrolysis-gas chromatography coupled to mass spectrometry to analyze chemically disparate samples, including living cells, geologically processed fossil organic material, carbon-rich meteorites, and laboratory-synthesized organic compounds and mixtures. Data from each sample were employed as training and test subsets for machine-learning methods, which resulted in a model that can identify the biogenicity of both contemporary and ancient geologically processed samples with ~90% accuracy. These machine-learning methods do not rely on precise compound identification: Rather, the relational aspects of chromatographic and mass peaks provide the needed information, which underscores this method's utility for detecting alien biology.


Assuntos
Carbono , Emigrantes e Imigrantes , Humanos , Exobiologia , Fósseis , Aprendizado de Máquina
13.
Proc Natl Acad Sci U S A ; 120(29): e2221249120, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37410813

RESUMO

Asynchronous skeletal muscle degeneration/regeneration is a hallmark feature of Duchenne muscular dystrophy (DMD); however, traditional -omics technologies that lack spatial context make it difficult to study the biological mechanisms of how asynchronous regeneration contributes to disease progression. Here, using the severely dystrophic D2-mdx mouse model, we generated a high-resolution cellular and molecular spatial atlas of dystrophic muscle by integrating spatial transcriptomics and single-cell RNAseq datasets. Unbiased clustering revealed nonuniform distribution of unique cell populations throughout D2-mdx muscle that were associated with multiple regenerative timepoints, demonstrating that this model faithfully recapitulates the asynchronous regeneration observed in human DMD muscle. By probing spatiotemporal gene expression signatures, we found that propagation of inflammatory and fibrotic signals from locally damaged areas contributes to widespread pathology and that querying expression signatures within discrete microenvironments can identify targetable pathways for DMD therapy. Overall, this spatial atlas of dystrophic muscle provides a valuable resource for studying DMD disease biology and therapeutic target discovery.


Assuntos
Músculo Esquelético , Distrofia Muscular de Duchenne , Animais , Camundongos , Humanos , Músculo Esquelético/metabolismo , Camundongos Endogâmicos mdx , Distrofia Muscular de Duchenne/metabolismo , Progressão da Doença , Modelos Animais de Doenças
14.
Proc Natl Acad Sci U S A ; 120(32): e2309967120, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37523551

RESUMO

Body fat distribution is a heritable risk factor for cardiovascular and metabolic disease. In humans, rare Inhibin beta E (INHBE, activin E) loss-of-function variants are associated with a lower waist-to-hip ratio and protection from type 2 diabetes. Hepatic fatty acid sensing promotes INHBE expression during fasting and in obese individuals, yet it is unclear how the hepatokine activin E governs body shape and energy metabolism. Here, we uncover activin E as a regulator of adipose energy storage. By suppressing ß-agonist-induced lipolysis, activin E promotes fat accumulation and adipocyte hypertrophy and contributes to adipose dysfunction in mice. Mechanistically, we demonstrate that activin E elicits its effect on adipose tissue through ACVR1C, activating SMAD2/3 signaling and suppressing PPARG target genes. Conversely, loss of activin E or ACVR1C in mice increases fat utilization, lowers adiposity, and drives PPARG-regulated gene signatures indicative of healthy adipose function. Our studies identify activin E-ACVR1C as a metabolic rheostat promoting liver-adipose cross talk to restrain excessive fat breakdown and preserve fat mass during prolonged fasting, a mechanism that is maladaptive in obese individuals.


Assuntos
Diabetes Mellitus Tipo 2 , Lipólise , Humanos , Camundongos , Animais , Ativinas/metabolismo , Adiposidade/genética , Diabetes Mellitus Tipo 2/metabolismo , PPAR gama/metabolismo , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Receptores de Ativinas Tipo I/genética , Receptores de Ativinas Tipo I/metabolismo
15.
Proc Natl Acad Sci U S A ; 120(28): e2222035120, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37399402

RESUMO

Studies investigating the evolution of flowering plants have long focused on isolating mechanisms such as pollinator specificity. Some recent studies have proposed a role for introgressive hybridization between species, recognizing that isolating processes such as pollinator specialization may not be complete barriers to hybridization. Occasional hybridization may therefore lead to distinct yet reproductively connected lineages. We investigate the balance between introgression and reproductive isolation in a diverse clade using a densely sampled phylogenomic study of fig trees (Ficus, Moraceae). Codiversification with specialized pollinating wasps (Agaonidae) is recognized as a major engine of fig diversity, leading to about 850 species. Nevertheless, some studies have focused on the importance of hybridization in Ficus, highlighting the consequences of pollinator sharing. Here, we employ dense taxon sampling (520 species) throughout Moraceae and 1,751 loci to investigate phylogenetic relationships and the prevalence of introgression among species throughout the history of Ficus. We present a well-resolved phylogenomic backbone for Ficus, providing a solid foundation for an updated classification. Our results paint a picture of phylogenetically stable evolution within lineages punctuated by occasional local introgression events likely mediated by local pollinator sharing, illustrated by clear cases of cytoplasmic introgression that have been nearly drowned out of the nuclear genome through subsequent lineage fidelity. The phylogenetic history of figs thus highlights that while hybridization is an important process in plant evolution, the mere ability of species to hybridize locally does not necessarily translate into ongoing introgression between distant lineages, particularly in the presence of obligate plant-pollinator relationships.


Assuntos
Ficus , Vespas , Animais , Ficus/genética , Filogenia , Genômica , Isolamento Reprodutivo , Vespas/genética , Polinização/genética
16.
Pharmacol Rev ; 75(4): 758-788, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36918260

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by selective loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) region of the midbrain. The loss of neurons results in a subsequent reduction of dopamine in the striatum, which underlies the core motor symptoms of PD. To date, there are no effective treatments to stop, slow, or reverse the pathologic progression of dopaminergic neurodegeneration. This unfortunate predicament is because of the current early stages in understanding the biologic targets and pathways involved in PD pathogenesis. Ion channels have become emerging targets for new therapeutic development for PD due to their essential roles in neuronal function and neuroinflammation. Potassium channels are the most prominent ion channel family and have been shown to be critically important in PD pathology because of their roles in modulating neuronal excitability, neurotransmitter release, synaptic transmission, and neuroinflammation. In this review, members of the subfamilies of voltage-gated K+ channels, inward rectifying K+ channels, and Ca2+-activated K+ channels are described. Evidence of the role of these channels in PD etiology is discussed together with the latest views on related pathologic mechanisms and their potential as biologic targets for developing neuroprotective drugs for PD. SIGNIFICANCE STATEMENT: Parkinson's disease (PD) is the second most common neurodegenerative disorder, featuring progressive degeneration of dopaminergic neurons in the midbrain. It is a multifactorial disease involving multiple risk factors and complex pathobiological mechanisms. Mounting evidence suggests that ion channels play vital roles in the pathogenesis and progression of PD by regulating neuronal excitability and immune cell function. Therefore, they have become "hot" biological targets for PD, as demonstrated by multiple clinical trials of drug candidates targeting ion channels for PD therapy.


Assuntos
Produtos Biológicos , Doença de Parkinson , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Canais de Potássio/metabolismo , Canais de Potássio/uso terapêutico , Doenças Neuroinflamatórias , Canais Iônicos/metabolismo , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Produtos Biológicos/uso terapêutico
17.
Circulation ; 149(22): e1223-e1238, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38660790

RESUMO

Tricuspid valve disease is an often underrecognized clinical problem that is associated with significant morbidity and mortality. Unfortunately, patients will often present late in their disease course with severe right-sided heart failure, pulmonary hypertension, and life-limiting symptoms that have few durable treatment options. Traditionally, the only treatment for tricuspid valve disease has been medical therapy or surgery; however, there have been increasing interest and success with the use of transcatheter tricuspid valve therapies over the past several years to treat patients with previously limited therapeutic options. The tricuspid valve is complex anatomically, lying adjacent to important anatomic structures such as the right coronary artery and the atrioventricular node, and is the passageway for permanent pacemaker leads into the right ventricle. In addition, the mechanism of tricuspid pathology varies widely between patients, which can be due to primary, secondary, or a combination of causes, meaning that it is not possible for 1 type of device to be suitable for treatment of all cases of tricuspid valve disease. To best visualize the pathology, several modalities of advanced cardiac imaging are often required, including transthoracic echocardiography, transesophageal echocardiography, cardiac computed tomography, and cardiac magnetic resonance imaging, to best visualize the pathology. This detailed imaging provides important information for choosing the ideal transcatheter treatment options for patients with tricuspid valve disease, taking into account the need for the lifetime management of the patient. This review highlights the important background, anatomic considerations, therapeutic options, and future directions with regard to treatment of tricuspid valve disease.


Assuntos
American Heart Association , Valva Tricúspide , Humanos , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/patologia , Estados Unidos , Doenças das Valvas Cardíacas/terapia , Doenças das Valvas Cardíacas/diagnóstico por imagem , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Insuficiência da Valva Tricúspide/terapia , Implante de Prótese de Valva Cardíaca
18.
Lancet ; 403(10432): 1141-1152, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38461841

RESUMO

BACKGROUND: Intravitreal aflibercept 8 mg could improve treatment outcomes and provide sustained disease control in patients with neovascular age-related macular degeneration (nAMD), with extended dosing compared with aflibercept 2 mg. METHODS: PULSAR is a phase 3, randomised, three-group, double-masked, non-inferiority, 96-week trial conducted across 223 sites worldwide. Adults with nAMD were randomised 1:1:1 to aflibercept 8 mg every 12 weeks (8q12), aflibercept 8 mg every 16 weeks (8q16), or aflibercept 2 mg every 8 weeks (2q8), following three initial monthly doses in all groups. From week 16, patients in the aflibercept 8 mg groups had their dosing interval shortened if pre-specified dose regimen modification criteria denoting disease activity were met. The primary endpoint was change from baseline in best-corrected visual acuity (BCVA) at week 48. All patients with at least one dose of study treatment were included in the efficacy and safety analyses. This trial is registered with ClinicalTrials.gov (NCT04423718) and is ongoing. FINDINGS: Of 1011 patients randomised to aflibercept 8q12 (n=336), 8q16 (n=338), or 2q8 (n=337) between Aug 11, 2020, and July 30, 2021, 1009 patients received study treatment (aflibercept 8q12 n=335; aflibercept 8q16 n=338; and aflibercept 2q8 n=336). Aflibercept 8q12 and 8q16 showed non-inferior BCVA gains versus aflibercept 2q8 (mean BCVA change from baseline +6·7 [SD 12·6] and +6·2 [11·7] vs +7·6 [12·2] letters). The least squares mean differences between aflibercept 8q12 versus 2q8 and 8q16 versus 2q8, respectively, were -0·97 (95% CI -2·87 to 0·92) and -1·14 (-2·97 to 0·69) letters (non-inferiority margin at 4 letters). The incidence of ocular adverse events in the study eye was similar across groups (aflibercept 8q12 n=129 [39%]; aflibercept 8q16 n=127 [38%]; and aflibercept 2q8 n=130 [39%]). INTERPRETATION: Aflibercept 8 mg showed efficacy and safety with extended dosing intervals, which has the potential to improve the management of patients with nAMD. FUNDING: Bayer AG and Regeneron Pharmaceuticals.


Assuntos
Inibidores da Angiogênese , Degeneração Macular , Adulto , Humanos , Inibidores da Angiogênese/efeitos adversos , DEAE-Dextrano , Degeneração Macular/tratamento farmacológico , Receptores de Fatores de Crescimento do Endotélio Vascular/uso terapêutico , Proteínas Recombinantes de Fusão/efeitos adversos , Resultado do Tratamento
19.
Lancet ; 403(10427): 645-656, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38278170

RESUMO

BACKGROUND: CD55 deficiency with hyperactivation of complement, angiopathic thrombosis, and protein-losing enteropathy (CHAPLE) is an ultra-rare genetic disorder characterised by intestinal lymphatic damage, lymphangiectasia, and protein-losing enteropathy caused by overactivation of the complement system. We assessed the efficacy and safety of pozelimab, an antibody blocking complement component 5. METHODS: This open-label, single-arm, historically controlled, multicentre phase 2 and 3 study evaluated ten patients with CHAPLE disease. This study was conducted at three hospitals in Thailand, Türkiye, and the USA. Patients aged 1 year or older with a clinical diagnosis of CHAPLE disease and a CD55 loss-of-function variant identified by genetic analysis and confirmed by flow cytometry or western blot of CD55 from peripheral blood cells were eligible for this study. Patients received a single intravenous loading dose of pozelimab 30 mg per kg of bodyweight, followed by a once-per-week subcutaneous dose over the treatment period based on bodyweight at a concentration of 200 mg/mL as either a single injection (<40 kg bodyweight) or two injections (≥40 kg bodyweight). The primary endpoint was proportion of patients with serum albumin normalisation with an improvement in active clinical outcomes and no worsening in inactive clinical outcomes (frequency of problematic abdominal pain, bowel movement frequency, facial oedema severity, and peripheral oedema severity) at week 24 compared with baseline, assessed in the full analysis set. This study is registered with ClinicalTrials.gov (NCT04209634) and is active but not recruiting. FINDINGS: 11 patients were recruited between Jan 27, 2020, and May 12, 2021, ten of which were enrolled in the study and included in the analysis populations. The efficacy data corresponded to all patients completing the week 48 assessment and having at least 52 weeks of treatment exposure, and the safety data included an additional 90 days of follow-up and corresponded to all patients having at least 72 weeks of treatment. Patients were predominantly paediatric (with a median age of 8·5 years), and originated from Türkiye, Syria, Thailand, and Bolivia. Patients had markedly low weight-for-age and stature-for-age at baseline, and mean albumin at baseline was 2·2 g/dL, which was considerably less than the local laboratory reference range. After pozelimab treatment, all ten patients had serum albumin normalisation and improvement with no worsening in clinical outcomes. There was a complete inhibition of the total complement activity. Nine patients had adverse events; two were severe events, and one patient had an adverse event considered related to pozelimab. INTERPRETATION: Pozelimab inhibits complement overactivation and resolves the clinical and laboratory manifestations of CHAPLE disease. Pozelimab is the only currently approved therapeutic drug for patients with this life-threatening, ultra-rare condition. In patients with protein-losing enteropathy where known causes have been excluded, testing for a CD55 deficiency should be contemplated. A diagnosis of CHAPLE disease should lead to early consideration of treatment with pozelimab. FUNDING: Regeneron Pharmaceuticals and the Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health.


Assuntos
Enteropatias Perdedoras de Proteínas , Trombose , Criança , Humanos , Anticorpos Monoclonais , Edema , Enteropatias Perdedoras de Proteínas/tratamento farmacológico , Albumina Sérica , Resultado do Tratamento , Estudo Historicamente Controlado , Masculino , Feminino
20.
Lancet ; 403(10432): 1153-1163, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38461843

RESUMO

BACKGROUND: A high-dose formulation of intravitreal aflibercept (8 mg) could improve treatment outcomes in diabetic macular oedema (DMO) by requiring fewer injections than the standard comparator, aflibercept 2 mg. We report efficacy and safety results of aflibercept 8 mg versus 2 mg in patients with DMO. METHODS: PHOTON was a randomised, double-masked, non-inferiority, phase 2/3 trial performed at 138 hospitals and specialty retina clinics in seven countries. Eligible patients were adults aged 18 years or older with type 1 or 2 diabetes and centre-involved DMO. Patients were randomly assigned (1:2:1) to intravitreal aflibercept 2 mg every 8 weeks (2q8), aflibercept 8 mg every 12 weeks (8q12), or aflibercept 8 mg every 16 weeks (8q16), following initial monthly dosing. From week 16, dosing intervals for the aflibercept 8 mg groups were shortened if patients met prespecified dose regimen modification criteria denoting disease activity. The primary endpoint was change from baseline in best-corrected visual acuity (BCVA) at week 48 (non-inferiority margin of 4 letters). Efficacy and safety analyses included all randomly assigned patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov (NCT04429503). FINDINGS: Between June 29, 2020, and June 28, 2021, 970 patients were screened for eligibility. After exclusions, 660 patients were enrolled and randomly assigned to receive aflibercept 8q12 (n=329), 8q16 (n=164), or 2q8 (n=167); two patients were randomly assigned in error and did not receive treatment. 658 (99·7%) patients were treated and included in the full analysis set and safety analysis set (8q12 n=328, 8q16 n=163, and 2q8 n=167). Mean patient age was 62·3 years (SD 10·4). 401 (61%) patients were male. 471 (72%) patients were White. Aflibercept 8q12 and 8q16 demonstrated non-inferior BCVA gains to aflibercept 2q8 (BCVA mean change from baseline 8·8 letters [SD 9·0] in the 8q12 group, 7·9 letters [8·4] in the 8q16 group, and 9·2 letters [9·0] in the 2q8 group). The difference in least squares means was -0·57 letters (95% CI -2·26 to 1·13, p value for non-inferiority <0·0001) between 8q12 and 2q8 and -1·44 letters (-3·27 to 0·39, p value for non-inferiority 0·0031) between aflibercept 8q16 and 2q8. Proportions of patients with ocular adverse events in the study eye were similar across groups (8q12 n=104 [32%], 8q16 n=48 [29%], and 2q8 n=46 [28%]). INTERPRETATION: Aflibercept 8 mg demonstrated efficacy and safety with extended dosing intervals and could decrease treatment burden in patients with DMO. FUNDING: Regeneron Pharmaceuticals and Bayer.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Edema Macular , Adulto , Feminino , Humanos , Masculino , Inibidores da Angiogênese , Diabetes Mellitus/tratamento farmacológico , Edema Macular/etiologia , Edema Macular/induzido quimicamente , Receptores de Fatores de Crescimento do Endotélio Vascular/uso terapêutico , Proteínas Recombinantes de Fusão/efeitos adversos , Resultado do Tratamento , Pessoa de Meia-Idade , Idoso
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