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1.
Cell ; 184(15): 3998-4015.e19, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34157302

RESUMO

Foxp3+ T regulatory (Treg) cells promote immunological tumor tolerance, but how their immune-suppressive function is regulated in the tumor microenvironment (TME) remains unknown. Here, we used intravital microscopy to characterize the cellular interactions that provide tumor-infiltrating Treg cells with critical activation signals. We found that the polyclonal Treg cell repertoire is pre-enriched to recognize antigens presented by tumor-associated conventional dendritic cells (cDCs). Unstable cDC contacts sufficed to sustain Treg cell function, whereas T helper cells were activated during stable interactions. Contact instability resulted from CTLA-4-dependent downregulation of co-stimulatory B7-family proteins on cDCs, mediated by Treg cells themselves. CTLA-4-blockade triggered CD28-dependent Treg cell hyper-proliferation in the TME, and concomitant Treg cell inactivation was required to achieve tumor rejection. Therefore, Treg cells self-regulate through a CTLA-4- and CD28-dependent feedback loop that adjusts their population size to the amount of local co-stimulation. Its disruption through CTLA-4-blockade may off-set therapeutic benefits in cancer patients.


Assuntos
Antígeno CTLA-4/metabolismo , Retroalimentação Fisiológica , Neoplasias/imunologia , Linfócitos T Reguladores/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Antígenos CD28/metabolismo , Proliferação de Células , Células Dendríticas/imunologia , Proteínas de Fluorescência Verde/metabolismo , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia , Interleucina-2/metabolismo , Ligantes , Linfonodos/metabolismo , Ativação Linfocitária/imunologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fatores de Transcrição NFATC/metabolismo , Neoplasias/patologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Microambiente Tumoral
2.
Mol Cell ; 81(10): 2183-2200.e13, 2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-34019788

RESUMO

To separate causal effects of histone acetylation on chromatin accessibility and transcriptional output, we used integrated epigenomic and transcriptomic analyses following acute inhibition of major cellular lysine acetyltransferases P300 and CBP in hematological malignancies. We found that catalytic P300/CBP inhibition dynamically perturbs steady-state acetylation kinetics and suppresses oncogenic transcriptional networks in the absence of changes to chromatin accessibility. CRISPR-Cas9 screening identified NCOR1 and HDAC3 transcriptional co-repressors as the principal antagonists of P300/CBP by counteracting acetylation turnover kinetics. Finally, deacetylation of H3K27 provides nucleation sites for reciprocal methylation switching, a feature that can be exploited therapeutically by concomitant KDM6A and P300/CBP inhibition. Overall, this study indicates that the steady-state histone acetylation-methylation equilibrium functions as a molecular rheostat governing cellular transcription that is amenable to therapeutic exploitation as an anti-cancer regimen.


Assuntos
Biocatálise , Histonas/metabolismo , Oncogenes , Transcrição Gênica , Fatores de Transcrição de p300-CBP/metabolismo , Acetilação , Linhagem Celular , Cromatina/metabolismo , Proteínas Correpressoras/metabolismo , Sequência Conservada , Evolução Molecular , Redes Reguladoras de Genes , Genoma , Histona Desacetilases/metabolismo , Humanos , Cinética , Metilação , Modelos Biológicos , RNA Polimerase II/metabolismo
3.
Nature ; 606(7915): 797-803, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35705814

RESUMO

Treatment with therapy targeting BRAF and MEK (BRAF/MEK) has revolutionized care in melanoma and other cancers; however, therapeutic resistance is common and innovative treatment strategies are needed1,2. Here we studied a group of patients with melanoma who were treated with neoadjuvant BRAF/MEK-targeted therapy ( NCT02231775 , n = 51) and observed significantly higher rates of major pathological response (MPR; ≤10% viable tumour at resection) and improved recurrence-free survival (RFS) in female versus male patients (MPR, 66% versus 14%, P = 0.001; RFS, 64% versus 32% at 2 years, P = 0.021). The findings were validated in several additional cohorts2-4 of patients with unresectable metastatic melanoma who were treated with BRAF- and/or MEK-targeted therapy (n = 664 patients in total), demonstrating improved progression-free survival and overall survival in female versus male patients in several of these studies. Studies in preclinical models demonstrated significantly impaired anti-tumour activity in male versus female mice after BRAF/MEK-targeted therapy (P = 0.006), with significantly higher expression of the androgen receptor in tumours of male and female BRAF/MEK-treated mice versus the control (P = 0.0006 and P = 0.0025). Pharmacological inhibition of androgen receptor signalling improved responses to BRAF/MEK-targeted therapy in male and female mice (P = 0.018 and P = 0.003), whereas induction of androgen receptor signalling (through testosterone administration) was associated with a significantly impaired response to BRAF/MEK-targeted therapy in male and female patients (P = 0.021 and P < 0.0001). Together, these results have important implications for therapy.


Assuntos
Antagonistas de Receptores de Andrógenos , Melanoma , Quinases de Proteína Quinase Ativadas por Mitógeno , Terapia de Alvo Molecular , Proteínas Proto-Oncogênicas B-raf , Receptores Androgênicos , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Feminino , Humanos , Masculino , Melanoma/tratamento farmacológico , Melanoma/patologia , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Receptores Androgênicos/metabolismo , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Análise de Sobrevida
4.
EMBO J ; 42(21): e113975, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37718683

RESUMO

Paneth cells (PCs), a specialized secretory cell type in the small intestine, are increasingly recognized as having an essential role in host responses to microbiome and environmental stresses. Whether and how commensal and pathogenic microbes modify PC composition to modulate inflammation remain unclear. Using newly developed PC-reporter mice under conventional and gnotobiotic conditions, we determined PC transcriptomic heterogeneity in response to commensal and invasive microbes at single cell level. Infection expands the pool of CD74+ PCs, whose number correlates with auto or allogeneic inflammatory disease progressions in mice. Similar correlation was found in human inflammatory disease tissues. Infection-stimulated cytokines increase production of reactive oxygen species (ROS) and expression of a PC-specific mucosal pentraxin (Mptx2) in activated PCs. A PC-specific ablation of MyD88 reduced CD74+ PC population, thus ameliorating pathogen-induced systemic disease. A similar phenotype was also observed in mice lacking Mptx2. Thus, infection stimulates expansion of a PC subset that influences disease progression.


Assuntos
Microbiota , Celulas de Paneth , Humanos , Animais , Camundongos , Celulas de Paneth/metabolismo , Celulas de Paneth/patologia , Intestino Delgado , Inflamação/patologia , Citocinas/metabolismo
5.
Development ; 151(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38869008

RESUMO

Cofilin, an actin-severing protein, plays key roles in muscle sarcomere addition and maintenance. Our previous work found that Drosophila cofilin (DmCFL) knockdown in muscle causes progressive deterioration of muscle structure and function and produces features seen in nemaline myopathy caused by cofilin mutations. We hypothesized that disruption of actin cytoskeleton dynamics by DmCFL knockdown would impact other aspects of muscle development, and, thus, conducted an RNA-sequencing analysis that unexpectedly revealed upregulated expression of numerous neuromuscular junction (NMJ) genes. We found that DmCFL is enriched in the muscle postsynaptic compartment and that DmCFL muscle knockdown causes F-actin disorganization in this subcellular domain prior to the sarcomere defects observed later in development. Despite NMJ gene expression changes, we found no significant changes in gross presynaptic Bruchpilot active zones or total postsynaptic glutamate receptor levels. However, DmCFL knockdown resulted in mislocalization of GluRIIA class glutamate receptors in more deteriorated muscles and strongly impaired NMJ transmission strength. These findings expand our understanding of the roles of cofilin in muscle to include NMJ structural development and suggest that NMJ defects may contribute to the pathophysiology of nemaline myopathy.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Junção Neuromuscular , Transmissão Sináptica , Animais , Junção Neuromuscular/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Fatores de Despolimerização de Actina/metabolismo , Fatores de Despolimerização de Actina/genética , Actinas/metabolismo , Sarcômeros/metabolismo , Técnicas de Silenciamento de Genes , Citoesqueleto de Actina/metabolismo , Miopatias da Nemalina/metabolismo , Miopatias da Nemalina/genética , Miopatias da Nemalina/patologia
6.
PLoS Biol ; 21(1): e3001969, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36701299

RESUMO

Noonan syndrome (NS) and NS with multiple lentigines (NSML) cognitive dysfunction are linked to SH2 domain-containing protein tyrosine phosphatase-2 (SHP2) gain-of-function (GoF) and loss-of-function (LoF), respectively. In Drosophila disease models, we find both SHP2 mutations from human patients and corkscrew (csw) homolog LoF/GoF elevate glutamatergic transmission. Cell-targeted RNAi and neurotransmitter release analyses reveal a presynaptic requirement. Consistently, all mutants exhibit reduced synaptic depression during high-frequency stimulation. Both LoF and GoF mutants also show impaired synaptic plasticity, including reduced facilitation, augmentation, and post-tetanic potentiation. NS/NSML diseases are characterized by elevated MAPK/ERK signaling, and drugs suppressing this signaling restore normal neurotransmission in mutants. Fragile X syndrome (FXS) is likewise characterized by elevated MAPK/ERK signaling. Fragile X Mental Retardation Protein (FMRP) binds csw mRNA and neuronal Csw protein is elevated in Drosophila fragile X mental retardation 1 (dfmr1) nulls. Moreover, phosphorylated ERK (pERK) is increased in dfmr1 and csw null presynaptic boutons. We find presynaptic pERK activation in response to stimulation is reduced in dfmr1 and csw nulls. Trans-heterozygous csw/+; dfmr1/+ recapitulate elevated presynaptic pERK activation and function, showing FMRP and Csw/SHP2 act within the same signaling pathway. Thus, a FMRP and SHP2 MAPK/ERK regulative mechanism controls basal and activity-dependent neurotransmission strength.


Assuntos
Proteínas de Drosophila , Proteína do X Frágil da Deficiência Intelectual , Animais , Humanos , Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Proteína do X Frágil da Deficiência Intelectual/genética , Transmissão Sináptica , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo
7.
Nature ; 586(7830): 623-627, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32814343

RESUMO

During meiosis, crossover recombination connects homologous chromosomes to direct their accurate segregation1. Defective crossing over causes infertility, miscarriage and congenital disease. Each pair of chromosomes attains at least one crossover via the formation and biased resolution of recombination intermediates known as double Holliday junctions2,3. A central principle of crossover resolution is that the two Holliday junctions are resolved in opposite planes by targeting nuclease incisions to specific DNA strands4. The endonuclease activity of the MutLγ complex has been implicated in the resolution of crossovers5-10, but the mechanisms that activate and direct strand-specific cleavage remain unknown. Here we show that the sliding clamp PCNA is important for crossover-biased resolution. In vitro assays with human enzymes show that PCNA and its loader RFC are sufficient to activate the MutLγ endonuclease. MutLγ is further stimulated by a co-dependent activity of the pro-crossover factors EXO1 and MutSγ, the latter of which binds Holliday junctions11. MutLγ also binds various branched DNAs, including Holliday junctions, but does not show canonical resolvase activity, implying that the endonuclease incises adjacent to junction branch points to achieve resolution. In vivo, RFC facilitates MutLγ-dependent crossing over in budding yeast. Furthermore, PCNA localizes to prospective crossover sites along synapsed chromosomes. These data highlight similarities between crossover resolution and the initiation steps of DNA mismatch repair12,13 and evoke a novel model for crossover-specific resolution of double Holliday junctions during meiosis.


Assuntos
Troca Genética , Endonucleases/metabolismo , Meiose , Proteínas MutL/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , DNA Cruciforme/química , DNA Cruciforme/genética , DNA Cruciforme/metabolismo , Ativação Enzimática , Humanos , Hidrólise , Masculino , Camundongos , Proteínas MutS/metabolismo , Ligação Proteica , Proteína de Replicação C/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
8.
Proc Natl Acad Sci U S A ; 120(49): e2305776120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38011563

RESUMO

Individuals with a history of early-life stress (ELS) tend to have an altered course of depression and lower treatment response rates. Research suggests that ELS alters brain development, but the molecular changes in the brain following ELS that may mediate altered antidepressant response have not been systematically studied. Sex and gender also impact the risk of depression and treatment response. Here, we leveraged existing RNA sequencing datasets from 1) blood samples from depressed female- and male-identifying patients treated with escitalopram or desvenlafaxine and assessed for treatment response or failure; 2) the nucleus accumbens (NAc) of female and male mice exposed to ELS and/or adult stress; and 3) the NAc of mice after adult stress, antidepressant treatment with imipramine or ketamine, and assessed for treatment response or failure. We find that transcriptomic signatures of adult stress after a history of ELS correspond with transcriptomic signatures of treatment nonresponse, across species and multiple classes of antidepressants. Transcriptomic correspondence with treatment outcome was stronger among females and weaker among males. We next pharmacologically tested these predictions in our mouse model of early-life and adult social defeat stress and treatment with either chronic escitalopram or acute ketamine. Among female mice, the strongest predictor of behavior was an interaction between ELS and ketamine treatment. Among males, however, early experience and treatment were poor predictors of behavior, mirroring our bioinformatic predictions. These studies provide neurobiological evidence for molecular adaptations in the brain related to sex and ELS that contribute to antidepressant treatment response.


Assuntos
Experiências Adversas da Infância , Ketamina , Humanos , Masculino , Feminino , Camundongos , Animais , Depressão/tratamento farmacológico , Depressão/genética , Escitalopram , Ketamina/farmacologia , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Resultado do Tratamento , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/genética
9.
Proc Natl Acad Sci U S A ; 120(7): e2210712120, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36745808

RESUMO

Whole-exome sequencing of Parkinson's disease (PD) patient DNA identified single-nucleotide polymorphisms (SNPs) in the tyrosine nonreceptor kinase-2 (TNK2) gene. Although this kinase had a previously demonstrated activity in preventing the endocytosis of the dopamine reuptake transporter (DAT), a causal role for TNK2-associated dysfunction in PD remains unresolved. We postulated the dopaminergic neurodegeneration resulting from patient-associated variants in TNK2 were a consequence of aberrant or prolonged TNK2 overactivity, the latter being a failure in TNK2 degradation by an E3 ubiquitin ligase, neuronal precursor cell-expressed developmentally down-regulated-4 (NEDD4). Interestingly, systemic RNA interference protein-3 (SID-3) is the sole TNK2 ortholog in the nematode Caenorhabditis elegans, where it is an established effector of epigenetic gene silencing mediated through the dsRNA-transporter, SID-1. We hypothesized that TNK2/SID-3 represents a node of integrated dopaminergic and epigenetic signaling essential to neuronal homeostasis. Use of a TNK2 inhibitor (AIM-100) or a NEDD4 activator [N-aryl benzimidazole 2 (NAB2)] in bioassays for either dopamine- or dsRNA-uptake into worm dopaminergic neurons revealed that sid-3 mutants displayed robust neuroprotection from 6-hydroxydopamine (6-OHDA) exposures, as did AIM-100 or NAB2-treated wild-type animals. Furthermore, NEDD4 activation by NAB2 in rat primary neurons correlated to a reduction in TNK2 levels and the attenuation of 6-OHDA neurotoxicity. CRISPR-edited nematodes engineered to endogenously express SID-3 variants analogous to TNK2 PD-associated SNPs exhibited enhanced susceptibility to dopaminergic neurodegeneration and circumvented the RNAi resistance characteristic of SID-3 dysfunction. This research exemplifies a molecular etiology for PD whereby dopaminergic and epigenetic signaling are coordinately regulated to confer susceptibility or resilience to neurodegeneration.


Assuntos
Doença de Parkinson , Animais , Ratos , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Dopamina/metabolismo , Oxidopamina , Neuroproteção/genética , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Neurônios Dopaminérgicos/metabolismo , Epigênese Genética , Modelos Animais de Doenças
10.
Proc Natl Acad Sci U S A ; 120(32): e2115616120, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37494421

RESUMO

Transfusion of red blood cells (RBCs) is one of the most valuable and widespread treatments in modern medicine. Lifesaving RBC transfusions are facilitated by the cold storage of RBC units in blood banks worldwide. Currently, RBC storage and subsequent transfusion practices are performed using simplistic workflows. More specifically, most blood banks follow the "first-in-first-out" principle to avoid wastage, whereas most healthcare providers prefer the "last-in-first-out" approach simply favoring chronologically younger RBCs. Neither approach addresses recent advances through -omics showing that stored RBC quality is highly variable depending on donor-, time-, and processing-specific factors. Thus, it is time to rethink our workflows in transfusion medicine taking advantage of novel technologies to perform RBC quality assessment. We imagine a future where lab-on-a-chip technologies utilize novel predictive markers of RBC quality identified by -omics and machine learning to usher in a new era of safer and precise transfusion medicine.


Assuntos
Preservação de Sangue , Procedimentos Analíticos em Microchip , Transfusão de Sangue/instrumentação , Transfusão de Sangue/métodos , Humanos , Preservação de Sangue/métodos , Dispositivos Lab-On-A-Chip , Eritrócitos , Aprendizado de Máquina
11.
J Neurosci ; 44(17)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38471782

RESUMO

Cytoplasmic protein tyrosine phosphatase nonreceptor type 11 (PTPN11) and Drosophila homolog Corkscrew (Csw) regulate the mitogen-activated protein kinase (MAPK) pathway via a conserved autoinhibitory mechanism. Disease-causing loss-of-function (LoF) and gain-of-function (GoF) mutations both disrupt this autoinhibition to potentiate MAPK signaling. At the Drosophila neuromuscular junction glutamatergic synapse, LoF/GoF mutations elevate transmission strength and reduce activity-dependent synaptic depression. In both sexes of LoF/GoF mutations, the synaptic vesicles (SV)-colocalized synapsin phosphoprotein tether is highly elevated at rest, but quickly reduced with stimulation, suggesting a larger SV reserve pool with greatly heightened activity-dependent recruitment. Transmission electron microscopy of mutants reveals an elevated number of SVs clustered at the presynaptic active zones, suggesting that the increased vesicle availability is causative for the elevated neurotransmission. Direct neuron-targeted extracellular signal-regulated kinase (ERK) GoF phenocopies both increased local presynaptic MAPK/ERK signaling and synaptic transmission strength in mutants, confirming the presynaptic regulatory mechanism. Synapsin loss blocks this elevation in both presynaptic PTPN11 and ERK mutants. However, csw null mutants cannot be rescued by wild-type Csw in neurons: neurotransmission is only rescued by expressing Csw in both neurons and glia simultaneously. Nevertheless, targeted LoF/GoF mutations in either neurons or glia alone recapitulate the elevated neurotransmission. Thus, PTPN11/Csw mutations in either cell type are sufficient to upregulate presynaptic function, but a dual requirement in neurons and glia is necessary for neurotransmission. Taken together, we conclude that PTPN11/Csw acts in both neurons and glia, with LoF and GoF similarly upregulating MAPK/ERK signaling to enhance presynaptic Synapsin-mediated SV trafficking.


Assuntos
Proteínas de Drosophila , Sistema de Sinalização das MAP Quinases , Neuroglia , Neurônios , Terminações Pré-Sinápticas , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Sinapsinas , Transmissão Sináptica , Vesículas Sinápticas , Animais , Feminino , Masculino , Animais Geneticamente Modificados , Drosophila , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Sistema de Sinalização das MAP Quinases/fisiologia , Mutação , Neuroglia/metabolismo , Neuroglia/fisiologia , Junção Neuromuscular/metabolismo , Junção Neuromuscular/fisiologia , Neurônios/metabolismo , Neurônios/fisiologia , Terminações Pré-Sinápticas/metabolismo , Terminações Pré-Sinápticas/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Sinapsinas/metabolismo , Sinapsinas/genética , Transmissão Sináptica/fisiologia , Vesículas Sinápticas/metabolismo
12.
Development ; 149(9)2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35394012

RESUMO

Both mRNA-binding Fragile X mental retardation protein (FMRP; Fmr1) and mRNA-binding Staufen regulate synaptic bouton formation and glutamate receptor (GluR) levels at the Drosophila neuromuscular junction (NMJ) glutamatergic synapse. Here, we tested whether these RNA-binding proteins act jointly in a common mechanism. We found that both dfmr1 and staufen mutants, and trans-heterozygous double mutants, displayed increased synaptic bouton formation and GluRIIA accumulation. With cell-targeted RNA interference, we showed a downstream Staufen role within postsynaptic muscle. With immunoprecipitation, we showed that FMRP binds staufen mRNA to stabilize postsynaptic transcripts. Staufen is known to target actin-binding, GluRIIA anchor Coracle, and we confirmed that Staufen binds to coracle mRNA. We found that FMRP and Staufen act sequentially to co-regulate postsynaptic Coracle expression, and showed that Coracle, in turn, controls GluRIIA levels and synaptic bouton development. Consistently, we found that dfmr1, staufen and coracle mutants elevate neurotransmission strength. We also identified that FMRP, Staufen and Coracle all suppress pMad activation, providing a trans-synaptic signaling linkage between postsynaptic GluRIIA levels and presynaptic bouton development. This work supports an FMRP-Staufen-Coracle-GluRIIA-pMad pathway regulating structural and functional synapse development.


Assuntos
Proteínas de Drosophila , Ácido Glutâmico , Animais , Drosophila , Proteínas de Drosophila/genética , Proteína do X Frágil da Deficiência Intelectual/genética , Terminações Pré-Sinápticas , RNA Mensageiro/genética , Receptores de Glutamato/genética , Sinapses
13.
PLoS Genet ; 18(8): e1010115, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35984862

RESUMO

The fine-tuning of gene expression is critical for all cellular processes; aberrations in this activity can lead to pathology, and conversely, resilience. As their role in coordinating organismal responses to both internal and external factors have increasingly come into focus, small non-coding RNAs have emerged as an essential component to disease etiology. Using Systemic RNA interference Defective (SID) mutants of the nematode Caenorhabditis elegans, deficient in gene silencing, we examined the potential consequences of dysfunctional epigenomic regulation in the context of Parkinson's disease (PD). Specifically, the loss of either the sid-1 or sid-3 genes, which encode a dsRNA transporter and an endocytic regulatory non-receptor tyrosine kinase, respectively, conferred neuroprotection to dopaminergic (DA) neurons in an established transgenic C. elegans strain wherein overexpression of human α-synuclein (α-syn) from a chromosomally integrated multicopy transgene causes neurodegeneration. We further show that knockout of a specific microRNA, mir-2, attenuates α-syn neurotoxicity; suggesting that the native targets of mir-2-dependent gene silencing represent putative neuroprotective modulators. In support of this, we demonstrated that RNAi knockdown of multiple mir-2 targets enhanced α-syn-induced DA neurodegeneration. Moreover, we demonstrate that mir-2 overexpression originating in the intestine can induce neurodegeneration of DA neurons, an effect that was reversed by pharmacological inhibition of SID-3 activity. Interestingly, sid-1 mutants retained mir-2-induced enhancement of neurodegeneration. Transcriptomic analysis of α-syn animals with and without a sid-1 mutation revealed 27 differentially expressed genes with human orthologs related to a variety of diseases, including PD. Among these was pgp-8, encoding a P-glycoprotein-related ABC transporter. Notably, sid-1; pgp-8 double mutants abolished the neurodegeneration resulting from intestinal mir-2 overexpression. This research positions known regulators of small RNA-dependent gene silencing within a framework that facilitates mechanistic evaluation of epigenetic responses to exogenous and endogenous factors influencing DA neurodegeneration, revealing a path toward new targets for therapeutic intervention of PD.


Assuntos
Proteínas de Caenorhabditis elegans , Doença de Parkinson , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Humanos , Doença de Parkinson/patologia , Interferência de RNA , RNA de Cadeia Dupla/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
14.
J Neurosci ; 43(34): 5996-6009, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37429717

RESUMO

Early-life stress (ELS) is one of the strongest lifetime risk factors for depression, anxiety, suicide, and other psychiatric disorders, particularly after facing additional stressful events later in life. Human and animal studies demonstrate that ELS sensitizes individuals to subsequent stress. However, the neurobiological basis of such stress sensitization remains largely unexplored. We hypothesized that ELS-induced stress sensitization would be detectable at the level of neuronal ensembles, such that cells activated by ELS would be more reactive to adult stress. To test this, we leveraged transgenic mice to genetically tag, track, and manipulate experience-activated neurons. We found that in both male and female mice, ELS-activated neurons within the nucleus accumbens (NAc), and to a lesser extent the medial prefrontal cortex, were preferentially reactivated by adult stress. To test whether reactivation of ELS-activated ensembles in the NAc contributes to stress hypersensitivity, we expressed hM4Dis receptor in control or ELS-activated neurons of pups and chemogenetically inhibited their activity during experience of adult stress. Inhibition of ELS-activated NAc neurons, but not control-tagged neurons, ameliorated social avoidance behavior following chronic social defeat stress in males. These data provide evidence that ELS-induced stress hypersensitivity is encoded at the level of corticolimbic neuronal ensembles.SIGNIFICANCE STATEMENT Early-life stress enhances sensitivity to stress later in life, yet the mechanisms of such stress sensitization are largely unknown. Here, we show that neuronal ensembles in corticolimbic brain regions remain hypersensitive to stress across the life span, and quieting these ensembles during experience of adult stress rescues stress hypersensitivity.


Assuntos
Experiências Adversas da Infância , Córtex Pré-Frontal , Adulto , Humanos , Masculino , Camundongos , Feminino , Animais , Córtex Pré-Frontal/fisiologia , Estresse Psicológico/psicologia , Neurônios , Ansiedade , Camundongos Transgênicos
15.
Emerg Infect Dis ; 30(6): 1203-1213, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38782023

RESUMO

Major dengue epidemics throughout Nicaragua's history have been dominated by 1 of 4 dengue virus serotypes (DENV-1-4). To examine serotypes during the dengue epidemic in Nicaragua in 2022, we performed real-time genomic surveillance in-country and documented cocirculation of all 4 serotypes. We observed a shift toward co-dominance of DENV-1 and DENV-4 over previously dominant DENV-2. By analyzing 135 new full-length DENV sequences, we found that introductions underlay the resurgence: DENV-1 clustered with viruses from Ecuador in 2014 rather than those previously seen in Nicaragua; DENV-3, which last circulated locally in 2014, grouped instead with Southeast Asia strains expanding into Florida and Cuba in 2022; and new DENV-4 strains clustered within a South America lineage spreading to Florida in 2022. In contrast, DENV-2 persisted from the formerly dominant Nicaragua clade. We posit that the resurgence emerged from travel after the COVID-19 pandemic and that the resultant intensifying hyperendemicity could affect future dengue immunity and severity.


Assuntos
COVID-19 , Vírus da Dengue , Dengue , Filogenia , SARS-CoV-2 , Sorogrupo , Vírus da Dengue/genética , Vírus da Dengue/classificação , Nicarágua/epidemiologia , Humanos , Dengue/epidemiologia , Dengue/virologia , COVID-19/epidemiologia , COVID-19/virologia , SARS-CoV-2/genética , Pandemias
16.
Cancer ; 130(7): 1061-1071, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38009662

RESUMO

BACKGROUND: Single-agent immune checkpoint inhibitors (ICIs) have demonstrated limited responses in recurrent ovarian cancer; however, 30%-40% of patients achieve stable disease. The primary objective was to estimate progression-free survival (PFS) after sequential versus combination cytotoxic T-lymphocyte antigen 4 and programmed death ligand 1 ICIs in patients with platinum-resistant high-grade serous ovarian cancer (HGSOC). METHODS: Patients were randomized to a sequential arm (tremelimumab followed by durvalumab on progression) or a combination arm (tremelimumab plus durvalumab, followed by durvalumab) via a Bayesian adaptive design that made it more likely for patients to be randomized to the more effective arm. The primary end point was immune-related PFS (irPFS). RESULTS: Sixty-one subjects were randomized to sequential (n = 38) or combination therapy (n = 23). Thirteen patients (34.2%) in the sequential arm received durvalumab. There was no difference in PFS in the sequential arm (1.84 months; 95% CI, 1.77-2.17 months) compared with the combination arm (1.87 months; 95% CI, 1.77-2.43 months) (p = .402). In the sequential arm, no responses were observed, although 12 patients (31.6%) demonstrated stable disease. In the combination arm, two patients (8.7%) had partial response, whereas one patient (4.4%) had stable disease. Adverse events were consistent with those previously reported for ICIs. Patient-reported outcomes were similar in both arms. CONCLUSIONS: There was no difference in irPFS for combination tremelimumab plus durvalumab compared to tremelimumab alone (administered as part of a sequential treatment strategy) in a heavily pretreated population of patients with platinum-resistant HGSOC. Response rates were comparable to prior reports, although the combination regimen did not add significant benefit, as has been previously described.


Assuntos
Anticorpos Monoclonais Humanizados , Anticorpos Monoclonais , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Ovarianas , Humanos , Feminino , Teorema de Bayes , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Inibidores de Checkpoint Imunológico , Neoplasias Ovarianas/tratamento farmacológico
17.
Ann Surg ; 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38258558

RESUMO

OBJECTIVE: Our objective was to determine the utility of enteral contrast-based protocols in the diagnosis and management of adhesive small bowel obstruction (ASBO) for children. BACKGROUND: Enteral contrast-based protocols for adults with ASBO are associated with decreased need for surgery and shorter hospitalization. Pediatric-specific data are limited. METHODS: We conducted a prospective observational study between October 2020 and December 2022 at nine children's hospitals who are members of the Western Pediatric Surgery Research Consortium. Inclusion criteria were children aged 1-20 years diagnosed with ASBO who underwent a trial of nonoperative management (NOM) at hospital admission. Comparisons were made between those children who received an enteral contrast challenge and those who did not. The primary outcome was need for surgery. RESULTS: We enrolled 136 children (71% male; median age: 12 y); 84 (62%) received an enteral contrast challenge. There was no difference in rate of operative intervention between the no contrast (34.6%) and contrast groups (36.9%; P=0.93). Eighty-seven (64%) were successfully managed nonoperatively with no difference in median length of stay (P=0.10) or rate of unplanned readmission (P=0.14). Among the 49 children who required an operation, there was no significant difference in time from admission to surgery or rate of small bowel resection based on prior contrast administration. CONCLUSIONS: The addition of enteral contrast-based protocols for management of pediatric ASBO does not decrease the likelihood of surgery or shorten hospitalization. Larger randomized studies may be needed to further define the role of radiologic contrast in the management of ASBO in children.

18.
J Pediatr ; 269: 113963, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38369237

RESUMO

OBJECTIVE: To evaluate for disparities in surgical care among US children with hepatoblastoma (HB) and hepatocellular carcinoma (HCC). STUDY DESIGN: In this retrospective National Cancer Database study (2004-2015), children aged <18 years with HB or HCC were included. Multivariable mixed-effects logistic regression was used to evaluate the association of sociodemographic factors (age, sex, race and ethnicity, insurance status, income, proximity to treating hospital) with the odds of undergoing surgical treatment after adjusting for disease-related factors (tumor size, metastasis, comorbidities) and hospital-level effects. Subgroup analyses by tumor histology were performed. RESULTS: A total of 811 children were included (HB: 80.9%; HCC: 19.1%), of which 610 (75.2%) underwent surgical treatment. Following adjustment, decreased odds of undergoing surgical treatment were associated with Black race (OR: 0.46 vs White, 95% CI [95% CI]: 0.26-0.80, P = .01), and having Medicaid (OR: 0.58 vs private, 95% CI: 0.38-0.88, P = .01) or no insurance (OR: 0.33 vs private, 95% CI: 0.13-0.80, P = .02). In children with HB, Black race was associated with decreased odds of undergoing surgical treatment (OR: 0.47 vs White, 95% CI: 0.25-0.89, P = .02). In children with HCC, Medicaid (OR: 0.10 vs private, 95% CI: 0.03-0.35, P < .001), or no insurance status (OR: 0.10 vs private, 95% CI: 0.01-0.83, P = .03) were associated with decreased odds of undergoing surgical treatment. Other than metastatic disease, no additional factors were associated with likelihood of surgical treatment in any group. CONCLUSIONS: Black race and having Medicaid or no insurance are independently associated with decreased odds of surgical treatment in children with HB and HCC, respectively. These children may be less likely to undergo curative surgery for their liver cancer.


Assuntos
Carcinoma Hepatocelular , Disparidades em Assistência à Saúde , Hepatoblastoma , Neoplasias Hepáticas , Humanos , Hepatoblastoma/cirurgia , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Masculino , Feminino , Criança , Estudos Retrospectivos , Pré-Escolar , Lactente , Estados Unidos , Disparidades em Assistência à Saúde/estatística & dados numéricos , Disparidades em Assistência à Saúde/etnologia , Adolescente , Fatores Sociodemográficos , Medicaid/estatística & dados numéricos , Fatores Socioeconômicos , Bases de Dados Factuais
19.
J Autoimmun ; 149: 103296, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39241536

RESUMO

Though the exact causes of systemic lupus erythematosus (SLE) remain unknown, exposure to ultraviolet (UV) light is one of the few well-known triggers of cutaneous inflammation in SLE. However, the precise cell types which contribute to the early cutaneous inflammatory response in lupus, and the ways that UV dosing and interferons modulate these findings, have not been thoroughly dissected. Here, we explore these questions using the NZM2328 spontaneous murine model of lupus. In addition, we use iNZM mice, which share the NZM2328 background but harbor a whole-body knockout of the type I interferon (IFN) receptor, and wild-type BALB/c mice. 10-13-week-old female mice of each strain were treated with acute (300 mJ/cm2 x1), chronic (100 mJ/cm2 daily x5 days), or no UVB, and skin was harvested and processed for bulk RNA sequencing and flow cytometry. We identify that inflammatory pathways and gene signatures related to myeloid cells - namely neutrophils and monocyte-derived dendritic cells - are a shared feature of the acute and chronic UVB response in NZM skin greater than iNZM and wild-type skin. We also verify recruitment and activation of these cells by flow cytometry in both acutely and chronically irradiated NZM and WT mice and demonstrate that these processes are dependent on type I IFN signaling. Taken together, these data indicate a skewed IFN-driven inflammatory response to both acute and chronic UVB exposure in lupus-prone skin dominated by myeloid cells, suggesting both the importance of type I IFNs and myeloid cells as therapeutic targets for photosensitive patients and highlighting the risks of even moderate UV exposure in this patient population.

20.
Ann Surg Oncol ; 31(3): 1980-1989, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38044348

RESUMO

BACKGROUND: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is the preferred treatment for select patients with peritoneal malignancies. However, the procedure is resource intensive and costly. This study aimed to determine the risk of financial toxicity for patients undergoing CRS-HIPEC. PATIENTS AND METHODS: We performed a retrospective cohort study of patients undergoing CRS-HIPEC at a single institution from 2016 to 2022. We utilized insurance status, out-of-pocket expenditures, and estimated post-subsistence income to determine risk of financial toxicity. A multivariable logistic regression was used to determine risk factors for financial toxicity. RESULTS: Our final study cohort consisted of 163 patients. Average age was 58 [standard deviation 10] years, and 52.8% (n = 86) were male. A total of 52 patients (31.9%) were at risk of financial toxicity. A total of 36 patients (22.1%) were from the lower income quartiles (first or second) and 127 patients (77.9%) were from the higher income quartiles (third or fourth). A total of 47 patients (29%) were insured by Medicare, and 116 patients (71%) had private insurance. The median out-of-pocket expenditure across the study cohort was $3500, with a median of $5000 ($3341-$7350) for the at-risk group and $3341 ($2500-$4022) for the not at-risk group (p < 0.001). Risk factors for financial toxicity included high out-of-pocket expenditures and a lower income quartile. CONCLUSIONS: An estimated one-third of patients undergoing CRS-HIPEC at our institution were at risk for financial toxicity. Several preoperative factors were associated with an increased risk and could be utilized to identify patients who might benefit from interventions.


Assuntos
Hipertermia Induzida , Quimioterapia Intraperitoneal Hipertérmica , Idoso , Humanos , Masculino , Estados Unidos , Pessoa de Meia-Idade , Feminino , Procedimentos Cirúrgicos de Citorredução , Estudos Retrospectivos , Estresse Financeiro , Quimioterapia do Câncer por Perfusão Regional , Medicare , Terapia Combinada , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Taxa de Sobrevida
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