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1.
Cell ; 186(9): 1824-1845, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37116469

RESUMO

Cachexia, a systemic wasting condition, is considered a late consequence of diseases, including cancer, organ failure, or infections, and contributes to significant morbidity and mortality. The induction process and mechanistic progression of cachexia are incompletely understood. Refocusing academic efforts away from advanced cachexia to the etiology of cachexia may enable discoveries of new therapeutic approaches. Here, we review drivers, mechanisms, organismal predispositions, evidence for multi-organ interaction, model systems, clinical research, trials, and care provision from early onset to late cachexia. Evidence is emerging that distinct inflammatory, metabolic, and neuro-modulatory drivers can initiate processes that ultimately converge on advanced cachexia.


Assuntos
Caquexia , Humanos , Caquexia/tratamento farmacológico , Caquexia/etiologia , Caquexia/metabolismo , Caquexia/patologia , Músculo Esquelético/metabolismo , Neoplasias/complicações , Neoplasias/metabolismo , Neoplasias/patologia , Infecções/complicações , Infecções/patologia , Insuficiência de Múltiplos Órgãos/complicações , Insuficiência de Múltiplos Órgãos/patologia
2.
Cell ; 181(4): 832-847.e18, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32304665

RESUMO

Obesity is a major modifiable risk factor for pancreatic ductal adenocarcinoma (PDAC), yet how and when obesity contributes to PDAC progression is not well understood. Leveraging an autochthonous mouse model, we demonstrate a causal and reversible role for obesity in early PDAC progression, showing that obesity markedly enhances tumorigenesis, while genetic or dietary induction of weight loss intercepts cancer development. Molecular analyses of human and murine samples define microenvironmental consequences of obesity that foster tumorigenesis rather than new driver gene mutations, including significant pancreatic islet cell adaptation in obesity-associated tumors. Specifically, we identify aberrant beta cell expression of the peptide hormone cholecystokinin (Cck) in response to obesity and show that islet Cck promotes oncogenic Kras-driven pancreatic ductal tumorigenesis. Our studies argue that PDAC progression is driven by local obesity-associated changes in the tumor microenvironment and implicate endocrine-exocrine signaling beyond insulin in PDAC development.


Assuntos
Carcinoma Ductal Pancreático/etiologia , Carcinoma Ductal Pancreático/metabolismo , Obesidade/metabolismo , Animais , Carcinogênese/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Modelos Animais de Doenças , Progressão da Doença , Células Endócrinas/metabolismo , Glândulas Exócrinas/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação/genética , Obesidade/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Transdução de Sinais/genética , Microambiente Tumoral/fisiologia , Neoplasias Pancreáticas
3.
Cell ; 172(1-2): 305-317.e10, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29328918

RESUMO

Phagocytic receptors must diffuse laterally to become activated upon clustering by multivalent targets. Receptor diffusion, however, can be obstructed by transmembrane proteins ("pickets") that are immobilized by interacting with the cortical cytoskeleton. The molecular identity of these pickets and their role in phagocytosis have not been defined. We used single-molecule tracking to study the interaction between Fcγ receptors and CD44, an abundant transmembrane protein capable of indirect association with F-actin, hence likely to serve as a picket. CD44 tethers reversibly to formin-induced actin filaments, curtailing receptor diffusion. Such linear filaments predominate in the trailing end of polarized macrophages, where receptor mobility was minimal. Conversely, receptors were most mobile at the leading edge, where Arp2/3-driven actin branching predominates. CD44 binds hyaluronan, anchoring a pericellular coat that also limits receptor displacement and obstructs access to phagocytic targets. Force must be applied to traverse the pericellular barrier, enabling receptors to engage their targets.


Assuntos
Citoesqueleto de Actina/metabolismo , Membrana Celular/metabolismo , Receptores de Hialuronatos/metabolismo , Receptores Imunológicos/metabolismo , Adulto , Animais , Sítios de Ligação , Células COS , Células Cultivadas , Chlorocebus aethiops , Feminino , Humanos , Receptores de Hialuronatos/química , Receptores de Hialuronatos/genética , Ácido Hialurônico/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica
4.
Proc Natl Acad Sci U S A ; 121(8): e2312152121, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38346195

RESUMO

Subsurface sandstone reservoirs sealed by overlying, low-permeability layers provide capacity for long-term sequestration of anthropogenic waste. Leakage can occur if reservoir pressures rise sufficiently to fracture the seal. Such pressures can be generated within the reservoir by vigorous injection of waste or, over thousands of years, by natural processes. In either case, the precise role of intercalated mudstones in the long-term evolution of reservoir pressure remains unclear; these layers have variously been viewed as seals, as pressure sinks, or as pressure sources. Here, we use the geological record of episodic fluid venting in the Levant Basin to provide striking evidence for the pressure-source hypothesis. We use a Bayesian framework to combine recently published venting data, which record critical subsurface pressures since ∼2 Ma, with a stochastic model of pressure evolution to infer a pressure-recharge rate of ∼30 MPa/Myr. To explain this large rate, we quantify and compare a range of candidate mechanisms. We find that poroelastic pressure diffusion from mudstones provides the most plausible explanation for these observations, amplifying the ∼3 MPa/Myr recharge caused primarily by tectonic compression. Since pressurized mudstones are ubiquitous in sedimentary basins, pressure diffusion from mudstones is likely to promote seal failure globally.

5.
Proc Natl Acad Sci U S A ; 121(11): e2400272121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38437534

RESUMO

The endothelial lining of cerebral microvessels is damaged relatively early after cerebral ischemia/reperfusion (I/R) injury and mediates blood-brain barrier (BBB) disruption, neurovascular injury, and long-term neurological deficits. I/R induces BBB leakage within 1 h due to subtle structural alterations in endothelial cells (ECs), including reorganization of the actin cytoskeleton and subcellular redistribution of junctional proteins. Herein, we show that the protein peroxiredoxin-4 (Prx4) is an endogenous protectant against endothelial dysfunction and BBB damage in a murine I/R model. We observed a transient upregulation of Prx4 in brain ECs 6 h after I/R in wild-type (WT) mice, whereas tamoxifen-induced, selective knockout of Prx4 from endothelial cells (eKO) mice dramatically raised vulnerability to I/R. Specifically, eKO mice displayed more BBB damage than WT mice within 1 to 24 h after I/R and worse long-term neurological deficits and focal brain atrophy by 35 d. Conversely, endothelium-targeted transgenic (eTG) mice overexpressing Prx4 were resistant to I/R-induced early BBB damage and had better long-term functional outcomes. As demonstrated in cultures of human brain endothelial cells and in animal models of I/R, Prx4 suppresses actin polymerization and stress fiber formation in brain ECs, at least in part by inhibiting phosphorylation/activation of myosin light chain. The latter cascade prevents redistribution of junctional proteins and BBB leakage under conditions of Prx4 repletion. Prx4 also tempers microvascular inflammation and infiltration of destructive neutrophils and proinflammatory macrophages into the brain parenchyma after I/R. Thus, the evidence supports an indispensable role for endothelial Prx4 in safeguarding the BBB and promoting functional recovery after I/R brain injury.


Assuntos
Barreira Hematoencefálica , AVC Isquêmico , Animais , Humanos , Camundongos , Atrofia , Células Endoteliais , Endotélio , Peroxirredoxinas
6.
N Engl J Med ; 388(10): 898-912, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36884323

RESUMO

BACKGROUND: Desmoid tumors are rare, locally aggressive, highly recurrent soft-tissue tumors without approved treatments. METHODS: We conducted a phase 3, international, double-blind, randomized, placebo-controlled trial of nirogacestat in adults with progressing desmoid tumors according to the Response Evaluation Criteria in Solid Tumors, version 1.1. Patients were assigned in a 1:1 ratio to receive the oral γ-secretase inhibitor nirogacestat (150 mg) or placebo twice daily. The primary end point was progression-free survival. RESULTS: From May 2019 through August 2020, a total of 70 patients were assigned to receive nirogacestat and 72 to receive placebo. Nirogacestat had a significant progression-free survival benefit over placebo (hazard ratio for disease progression or death, 0.29; 95% confidence interval, 0.15 to 0.55; P<0.001); the likelihood of being event-free at 2 years was 76% with nirogacestat and 44% with placebo. Between-group differences in progression-free survival were consistent across prespecified subgroups. The percentage of patients who had an objective response was significantly higher with nirogacestat than with placebo (41% vs. 8%; P<0.001), with a median time to response of 5.6 months and 11.1 months, respectively; the percentage of patients with a complete response was 7% and 0%, respectively. Significant between-group differences in secondary patient-reported outcomes, including pain, symptom burden, physical or role functioning, and health-related quality of life, were observed (P≤0.01). Frequent adverse events with nirogacestat included diarrhea (in 84% of the patients), nausea (in 54%), fatigue (in 51%), hypophosphatemia (in 42%), and maculopapular rash (in 32%); 95% of adverse events were of grade 1 or 2. Among women of childbearing potential receiving nirogacestat, 27 of 36 (75%) had adverse events consistent with ovarian dysfunction, which resolved in 20 women (74%). CONCLUSIONS: Nirogacestat was associated with significant benefits with respect to progression-free survival, objective response, pain, symptom burden, physical functioning, role functioning, and health-related quality of life in adults with progressing desmoid tumors. Adverse events with nirogacestat were frequent but mostly low grade. (Funded by SpringWorks Therapeutics; DeFi ClinicalTrials.gov number, NCT03785964.).


Assuntos
Antineoplásicos , Fibromatose Agressiva , Inibidores e Moduladores de Secretases gama , Tetra-Hidronaftalenos , Adulto , Feminino , Humanos , Secretases da Proteína Precursora do Amiloide/uso terapêutico , Antineoplásicos/uso terapêutico , Método Duplo-Cego , Fibromatose Agressiva/tratamento farmacológico , Inibidores e Moduladores de Secretases gama/uso terapêutico , Intervalo Livre de Progressão , Qualidade de Vida , Tetra-Hidronaftalenos/uso terapêutico , Valina/análogos & derivados
7.
N Engl J Med ; 389(10): 911-921, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37672694

RESUMO

BACKGROUND: Alveolar soft part sarcoma (ASPS) is a rare soft-tissue sarcoma with a poor prognosis and no established therapy. Recently, encouraging responses to immune checkpoint inhibitors have been reported. METHODS: We conducted an investigator-initiated, multicenter, single-group, phase 2 study of the anti-programmed death ligand 1 (PD-L1) agent atezolizumab in adult and pediatric patients with advanced ASPS. Atezolizumab was administered intravenously at a dose of 1200 mg (in patients ≥18 years of age) or 15 mg per kilogram of body weight with a 1200-mg cap (in patients <18 years of age) once every 21 days. Study end points included objective response, duration of response, and progression-free survival according to Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1, as well as pharmacodynamic biomarkers of multistep drug action. RESULTS: A total of 52 patients were evaluated. An objective response was observed in 19 of 52 patients (37%), with 1 complete response and 18 partial responses. The median time to response was 3.6 months (range, 2.1 to 19.1), the median duration of response was 24.7 months (range, 4.1 to 55.8), and the median progression-free survival was 20.8 months. Seven patients took a treatment break after 2 years of treatment, and their responses were maintained through the data-cutoff date. No treatment-related grade 4 or 5 adverse events were recorded. Responses were noted despite variable baseline expression of programmed death 1 and PD-L1. CONCLUSIONS: Atezolizumab was effective at inducing sustained responses in approximately one third of patients with advanced ASPS. (Funded by the National Cancer Institute and others; ClinicalTrials.gov number, NCT03141684.).


Assuntos
Anticorpos Monoclonais Humanizados , Antígeno B7-H1 , Sarcoma Alveolar de Partes Moles , Adolescente , Adulto , Criança , Humanos , Recém-Nascido , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Peso Corporal , Sarcoma Alveolar de Partes Moles/tratamento farmacológico , Administração Intravenosa
8.
Blood ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38820500

RESUMO

While initial therapy of mantle cell lymphoma (MCL) is not standardized, bendamustine-rituximab (BR) is commonly used in older patients. Rituximab (R) maintenance following induction is often utilized. Thus, the open-label, randomized phase II ECOG-ACRIN Cancer Research Group E1411 trial was designed to test two questions: 1) Does addition of bortezomib to BR induction (BVR) and/or 2) addition of lenalidomide to rituximab (LR) maintenance improve progression-free survival (PFS) in patients with treatment-naïve MCL? From 2012-2016, 373 previously untreated patients, 87% ≥ 60 years old, were enrolled in this trial. At a median follow up of 7.5 years, there is no difference in the median PFS of BR compared to BVR (5.5 yrs vs. 6.4 yrs, HR 0.90, 90% CI 0.70, 1.16). There were no unexpected additional toxicities with BVR treatment compared to BR, with no impact on total dose/duration of treatment received. Independent of the induction treatment, addition of lenalidomide to rituximab did not significantly improve PFS, with median PFS in R vs LR (5.9 yrs vs 7.2 yrs, HR 0.84 90% CI 0.62, 1.15). The majority of patients completed the planned 24 cycles of LR at the scheduled dose. In summary, adding bortezomib to BR induction does not prolong PFS in treatment-naïve MCL, and LR maintenance was not associated with longer PFS compared with rituximab alone following BR. Nonetheless, the > 5 year median PFS outcomes in this prospective cooperative group trial indicate the efficacy of BR followed by rituximab maintenance as highly effective initial therapy for older MCL patients. (NCT01415752).

9.
Blood ; 143(16): 1616-1627, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38215395

RESUMO

ABSTRACT: A041202 (NCT01886872) is a phase 3 study comparing bendamustine plus rituximab (BR) with ibrutinib and the combination of ibrutinib plus rituximab (IR) in previously untreated older patients with chronic lymphocytic leukemia (CLL). The initial results showed that ibrutinib-containing regimens had superior progression-free survival (PFS) and rituximab did not add additional benefits. Here we present an updated analysis. With a median follow-up of 55 months, the median PFS was 44 months (95% confidence interval [CI], 38-54) for BR and not yet reached in either ibrutinib-containing arm. The 48-month PFS estimates were 47%, 76%, and 76% for BR, ibrutinib, and IR, respectively. The benefit of ibrutinib regimens over chemoimmunotherapy was consistent across subgroups of patients defined by TP53 abnormalities, del(11q), complex karyotype, and immunoglobulin heavy chain variable region (IGHV). No significant interaction effects were observed between the treatment arm and del(11q), the complex karyotype, or IGHV. However, a greater difference in PFS was observed among the patients with TP53 abnormalities. There was no difference in the overall survival. Notable adverse events with ibrutinib included atrial fibrillation (afib) and hypertension. Afib was observed in 11 patients (pts) on BR (3%) and 67 pts on ibrutinib (18%). All-grade hypertension was observed in 95 pts on BR (27%) and 263 pts on ibrutinib (55%). These data show that ibrutinib regimens prolong PFS compared with BR for older patients with treatment-naïve CLL. These benefits were observed across subgroups, including high-risk groups. Strikingly, within the ibrutinib arms, there was no inferior PFS for patients with abnormalities in TP53, the highest risk feature observed in CLL. These data continue to demonstrate the efficacy of ibrutinib in treatment-naïve CLL.


Assuntos
Adenina/análogos & derivados , Fibrilação Atrial , Hipertensão , Leucemia Linfocítica Crônica de Células B , Piperidinas , Humanos , Idoso , Rituximab/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Seguimentos , Fibrilação Atrial/etiologia , Cloridrato de Bendamustina/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Hipertensão/etiologia
10.
Circ Res ; 134(6): 727-747, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38484027

RESUMO

The blood-brain barrier (BBB) is a critical interface separating the central nervous system from the peripheral circulation, ensuring brain homeostasis and function. Recent research has unveiled a profound connection between the BBB and circadian rhythms, the endogenous oscillations synchronizing biological processes with the 24-hour light-dark cycle. This review explores the significance of circadian rhythms in the context of BBB functions, with an emphasis on substrate passage through the BBB. Our discussion includes efflux transporters and the molecular timing mechanisms that regulate their activities. A significant focus of this review is the potential implications of chronotherapy, leveraging our knowledge of circadian rhythms for improving drug delivery to the brain. Understanding the temporal changes in BBB can lead to optimized timing of drug administration, to enhance therapeutic efficacy for neurological disorders while reducing side effects. By elucidating the interplay between circadian rhythms and drug transport across the BBB, this review offers insights into innovative therapeutic interventions.


Assuntos
Barreira Hematoencefálica , Relógios Circadianos , Barreira Hematoencefálica/fisiologia , Ritmo Circadiano , Encéfalo , Transporte Biológico , Sistemas de Liberação de Medicamentos , Relógios Circadianos/fisiologia
11.
Proc Natl Acad Sci U S A ; 120(8): e2203448120, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36780525

RESUMO

In applications critical to the geological, materials, and engineering sciences, deformation occurs at strain rates too small to be accessible experimentally. Instead, extrapolations of empirical relationships are used, leading to epistemic uncertainties in predictions. To address these problems, we construct a theory of the fundamental processes affecting dislocations: storage and recovery. We then validate our theory for olivine deformation. This model explains the empirical relationships among strain rate, applied stress, and dislocation density in disparate laboratory regimes. It predicts the previously unexplained dependence of dislocation density on applied stress in olivine. The predictions of our model for Earth conditions differ from extrapolated empirical relationships. For example, it predicts rapid, transient deformation in the upper mantle, consistent with recent measurements of postseismic creep.

12.
J Neurosci ; 44(25)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38719449

RESUMO

Decreased neuronal specificity of the brain in response to cognitive demands (i.e., neural dedifferentiation) has been implicated in age-related cognitive decline. Investigations into functional connectivity analogs of these processes have focused primarily on measuring segregation of nonoverlapping networks at rest. Here, we used an edge-centric network approach to derive entropy, a measure of specialization, from spatially overlapping communities during cognitive task fMRI. Using Human Connectome Project Lifespan data (713 participants, 36-100 years old, 55.7% female), we characterized a pattern of nodal despecialization differentially affecting the medial temporal lobe and limbic, visual, and subcortical systems. At the whole-brain level, global entropy moderated declines in fluid cognition across the lifespan and uniquely covaried with age when controlling for the network segregation metric modularity. Importantly, relationships between both metrics (entropy and modularity) and fluid cognition were age dependent, although entropy's relationship with cognition was specific to older adults. These results suggest entropy is a potentially important metric for examining how neurological processes in aging affect functional specialization at the nodal, network, and whole-brain level.


Assuntos
Envelhecimento , Encéfalo , Cognição , Conectoma , Entropia , Imageamento por Ressonância Magnética , Rede Nervosa , Humanos , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Adulto , Envelhecimento/fisiologia , Envelhecimento/psicologia , Cognição/fisiologia , Idoso de 80 Anos ou mais , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Rede Nervosa/fisiologia , Rede Nervosa/diagnóstico por imagem
13.
Hum Mol Genet ; 32(15): 2411-2421, 2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37154571

RESUMO

We assessed the relationship of gene copy number variation (CNV) in mental health/neurodevelopmental traits and diagnoses, physical health and cognition in a community sample of 7100 unrelated children and youth of European or East Asian ancestry (Spit for Science). Clinically significant or susceptibility CNVs were present in 3.9% of participants and were associated with elevated scores on a continuous measure of attention-deficit/hyperactivity disorder (ADHD) traits (P = 5.0 × 10-3), longer response inhibition (a cognitive deficit found in several mental health and neurodevelopmental disorders; P = 1.0 × 10-2) and increased prevalence of mental health diagnoses (P = 1.9 × 10-6, odds ratio: 3.09), specifically ADHD, autism spectrum disorder anxiety and learning problems/learning disorder (P's < 0.01). There was an increased burden of rare deletions in gene-sets related to brain function or expression in brain associated with more ADHD traits. With the current mental health crisis, our data established a baseline for delineating genetic contributors in pediatric-onset conditions.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Adolescente , Humanos , Criança , Saúde Mental , Variações do Número de Cópias de DNA/genética , Transtorno do Espectro Autista/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/genética , Dosagem de Genes
14.
Blood ; 141(25): 3031-3038, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37084383

RESUMO

Severe aplastic anemia (SAA) is a marrow failure disorder with high morbidity and mortality. It is treated with bone marrow transplantation (BMT) for those with fully matched donors, or immunosuppressive therapy (IST) for those who lack such a donor, which is often the case for underrepresented minorities. We conducted a prospective phase 2 trial of reduced-intensity conditioning HLA-haploidentical BMT and posttransplantation cyclophosphamide (PTCy)-based graft-versus-host (GVHD) prophylaxis as initial therapy for patients with SAA. The median patient age was 25 years (range, 3-63 years), and the median follow-up time was 40.9 months (95% confidence interval [CI], 29.4-55.7). More than 35% of enrollment was from underrepresented racial/ethnic groups. The cumulative incidence of grade 2 or 4 acute GVHD on day 100 was 7% (95% CI, not applicable [NA]-17), and chronic GVHD at 2 years was 4% (95% CI, NA-11). The overall survival of 27 patients was 92% (95% CI, 83-100) at 1, 2, and 3 years. The first 7 patients received lower dose total body irradiation (200 vs 400 cGy), but these patients were more likely to have graft failure (3 of 7) compared with 0 of 20 patients in the higher dose group (P = .01; Fisher exact test). HLA-haploidentical BMT with PTCy using 400 cGy total body irradiation resulted in 100% overall survival with minimal GVHD in 20 consecutive patients. Not only does this approach avoid any adverse ramifications of IST and its low failure-free survival, but the use of haploidentical donors also expands access to BMT across all populations. This trial was registered at www.clinicaltrials.gov as NCT02833805.


Assuntos
Anemia Aplástica , Doença Enxerto-Hospedeiro , Humanos , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Transplante de Medula Óssea/efeitos adversos , Estudos Prospectivos , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Ciclofosfamida/uso terapêutico
15.
Blood ; 141(8): 904-916, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36201743

RESUMO

Burkitt lymphoma (BL) accounts for most pediatric non-Hodgkin lymphomas, being less common but significantly more lethal when diagnosed in adults. Much of the knowledge of the genetics of BL thus far has originated from the study of pediatric BL (pBL), leaving its relationship to adult BL (aBL) and other adult lymphomas not fully explored. We sought to more thoroughly identify the somatic changes that underlie lymphomagenesis in aBL and any molecular features that associate with clinical disparities within and between pBL and aBL. Through comprehensive whole-genome sequencing of 230 BL and 295 diffuse large B-cell lymphoma (DLBCL) tumors, we identified additional significantly mutated genes, including more genetic features that associate with tumor Epstein-Barr virus status, and unraveled new distinct subgroupings within BL and DLBCL with 3 predominantly comprising BLs: DGG-BL (DDX3X, GNA13, and GNAI2), IC-BL (ID3 and CCND3), and Q53-BL (quiet TP53). Each BL subgroup is characterized by combinations of common driver and noncoding mutations caused by aberrant somatic hypermutation. The largest subgroups of BL cases, IC-BL and DGG-BL, are further characterized by distinct biological and gene expression differences. IC-BL and DGG-BL and their prototypical genetic features (ID3 and TP53) had significant associations with patient outcomes that were different among aBL and pBL cohorts. These findings highlight shared pathogenesis between aBL and pBL, and establish genetic subtypes within BL that serve to delineate tumors with distinct molecular features, providing a new framework for epidemiologic, diagnostic, and therapeutic strategies.


Assuntos
Linfoma de Burkitt , Infecções por Vírus Epstein-Barr , Linfoma Difuso de Grandes Células B , Criança , Humanos , Adulto , Linfoma de Burkitt/patologia , Herpesvirus Humano 4 , Linfoma Difuso de Grandes Células B/patologia , Mutação
16.
CA Cancer J Clin ; 68(2): 116-132, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29194581

RESUMO

Hodgkin lymphoma (HL) is a unique hematopoietic neoplasm characterized by cancerous Reed-Sternberg cells in an inflammatory background. Patients are commonly diagnosed with HL in their 20s and 30s, and they present with supradiaphragmatic lymphadenopathy, often with systemic B symptoms. Even in advanced-stage disease, HL is highly curable with combination chemotherapy, radiation, or combined-modality treatment. Although the same doxorubicin, bleomycin, vinblastine, and dacarbazine chemotherapeutic regimen has been the mainstay of therapy over the last 30 years, risk-adapted approaches have helped de-escalate therapy in low-risk patients while intensifying treatment for higher risk patients. Even patients who are not cured with initial therapy can often be salvaged with alternate chemotherapy combinations, the novel antibody-drug conjugate brentuximab, or high-dose autologous or allogeneic hematopoietic stem cell transplantation. The programmed death-1 inhibitors nivolumab and pembrolizumab have both demonstrated high response rates and durable remissions in patients with relapsed/refractory HL. Alternate donor sources and reduced-intensity conditioning have made allogeneic hematopoietic stem cell transplantation a viable option for more patients. Future research will look to integrate novel strategies into earlier lines of therapy to improve the HL cure rate and minimize long-term treatment toxicities. CA Cancer J Clin 2018;68:116-132. © 2017 American Cancer Society.


Assuntos
Doença de Hodgkin/diagnóstico , Doença de Hodgkin/terapia , Protocolos de Quimioterapia Combinada Antineoplásica , Biomarcadores Tumorais/sangue , Terapia Combinada , Diagnóstico Diferencial , Diagnóstico por Imagem , Transplante de Células-Tronco Hematopoéticas , Doença de Hodgkin/mortalidade , Doença de Hodgkin/patologia , Humanos , Estadiamento de Neoplasias , Prognóstico , Fatores de Risco , Análise de Sobrevida , Condicionamento Pré-Transplante/tendências
17.
Cell ; 141(4): 717-27, 2010 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-20478260

RESUMO

Induction of senescence permanently restricts cellular proliferation after oncogenic stimulation thereby acting as a potent barrier to tumor development. The relevant effector proteins may therefore be fundamental to cancer development. A recent study identified IGFBP7 as a secreted factor mediating melanocyte senescence induced by oncogenic B-RAF, which is found commonly in cutaneous nevi. In contrast to the previous report, we demonstrate that B-RAF signaling does not induce IGFBP7 expression, nor the expression of the IGFBP7 targets, BNIP3L, SMARCB1, or PEA15, in human melanocytes or fibroblasts. We also found no correlation between B-RAF mutational status and IGFBP7 protein expression levels in 22 melanoma cell lines, 90 melanomas, and 46 benign nevi. Furthermore, using a lentiviral silencing strategy we show that B-RAF induces senescence in melanocytes and fibroblasts, irrespective of the presence of IGFBP7. Therefore, we conclude that the secreted protein IGFBP7 is dispensable for B-RAF(V600E)-induced senescence in human melanocytes.


Assuntos
Senescência Celular , Melanoma/metabolismo , Neoplasias Cutâneas/metabolismo , Linhagem Celular Tumoral , Humanos , Melanócitos/citologia , Melanócitos/metabolismo , Proteínas Proto-Oncogênicas B-raf
18.
Proc Natl Acad Sci U S A ; 119(28): e2204761119, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35867751

RESUMO

It is established that changes in sea level influence melt production at midocean ridges, but whether changes in melt production influence the pattern of bathymetry flanking midocean ridges has been debated on both theoretical and empirical grounds. To explore the dynamics that may give rise to a sea-level influence on bathymetry, we simulate abyssal hills using a faulting model with periodic variations in melt supply. For 100-ky melt-supply cycles, model results show that faults initiate during periods of amagmatic spreading at half-rates >2.3 cm/y and for 41-ky melt-supply cycles at half-rates >3.8 cm/y. Analysis of bathymetry across 17 midocean ridge regions shows characteristic wavelengths that closely align with the predictions from the faulting model. At intermediate-spreading ridges (half-rates >2.3 cm/y and [Formula: see text]3.8 cm/y) abyssal hill spacing increases with spreading rate at 0.99 km/(cm/y) or 99 ky (n [Formula: see text] 12; 95% CI, 87 to 110 ky), and at fast-spreading ridges (half-rates >3.8 cm/y) spacing increases at 38 ky (n [Formula: see text] 5; 95% CI, 29 to 47 ky). Including previously published analyses of abyssal-hill spacing gives a more precise alignment with the primary periods of Pleistocene sea-level variability. Furthermore, analysis of bathymetry from fast-spreading ridges shows a highly statistically significant spectral peak (P < 0.01) at the 1/(41-ky) period of Earth's variations in axial tilt. Faulting models and observations both support a linkage between glacially induced sea-level change and the fabric of the sea floor over the late Pleistocene.

19.
Nano Lett ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38620021

RESUMO

Dual heterostructures integrating noble-metal and copper chalcogenide nanoparticles have attracted a great deal of attention in nonlinear optics, because coupling of their localized surface plasmon resonances (LSPRs) substantially enhances light-matter interactions through local-field effects. Previously, enhanced cascaded third-harmonic generation was demonstrated in Au/CuS heterostructures mediated by harmonically coupled surface plasmon resonances. This suggests a promising approach for extending nonlinear enhancement to higher harmonics by adding an additional nanoparticulate material with higher-frequency harmonic resonances to the hybrid films. Here we report the first observation of enhanced cascaded fourth- and fifth-harmonic generation in Al/Au/CuS driven by coupled LSPRs at the fundamental (1050 nm), second harmonic (525 nm), and third harmonic (350 nm) of the pump frequency. An analytical model based on incoherent dipole-dipole interactions among plasmonic nanoparticles accounts for the observed enhancements. The results suggest a novel design for efficiently generating higher harmonics in resonant plasmonic structures by means of multiple sum-frequency cascades.

20.
Int J Cancer ; 155(4): 618-626, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38721724

RESUMO

Immunocompromised patients are at high risk to fail clearance of SARS-CoV-2. Prolonged COVID-19 constitutes a health risk and a management problem as cancer treatments often have to be disrupted. As SARS-CoV-2 evolves, new variants of concern have emerged that evade available monoclonal antibodies. Moreover, antiviral therapy promotes SARS-CoV-2 escape mutations, particularly in immunocompromised patients. These patients frequently suffer from prolonged infection. No successful treatment has been established for persistent COVID-19 infection. Here, we report on a series of 21 immunocompromised patients with COVID-19-most of them hematologic malignancies-treated with plasma obtained from recently convalescent or vaccinated donors or a combination thereof. Repeated dosing of SARS-CoV-2-antibody-containing plasma could clear SARS-CoV-2 infection in 16 out of 21 immunocompromised patients even if COVID-19-specific treatments failed to induce sustained viral clearance or to improve clinical course of SARS-CoV-2 infection. Ten patients were major responders defined as an increase delta(d)Ct of > = 5 after the first administration of convalescent and/or vaccinated plasma (C/VP). On average, SARS-CoV-2 PCR Ct values increased from a median value of 22.55 (IQR = 19.10-24.25) to a median value of 29.57 (IQR = 27.55-34.63; p = <.0001) in the major response subgroup. Furthermore, when treated a second time with C/VP, even 4 out of 5 of the initial nonresponders showed an increase in Ct-values from a median value of 23.13 (IQR = 17.75-28.05) to a median value of 32.79 (IQR = 31.75-33.75; p = .013). Our results suggest that C/VP could be a feasible treatment of COVID-19 infection in patients with hematologic malignancies who did not respond to antiviral treatment.


Assuntos
Soroterapia para COVID-19 , COVID-19 , Neoplasias Hematológicas , Imunização Passiva , Hospedeiro Imunocomprometido , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/virologia , COVID-19/prevenção & controle , COVID-19/terapia , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/virologia , Feminino , Pessoa de Meia-Idade , Masculino , Idoso , SARS-CoV-2/imunologia , Imunização Passiva/métodos , Hospedeiro Imunocomprometido/imunologia , Adulto , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Doença Crônica , Resultado do Tratamento
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