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1.
J Clin Invest ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38885332

RESUMO

Most children with medulloblastoma (MB) achieve remission, but some face very aggressive metastatic tumors. Their dismal outcome highlights the critical need to advance therapeutic approaches that benefit such high-risk patients. Minnelide, a clinically relevant analog of the natural product triptolide, has oncostatic activity in both preclinical and early clinical settings. Despite its efficacy and tolerable toxicity, this compound has not been evaluated in MB. Utilizing a bioinformatic dataset that integrates cellular drug response data with gene expression, we predicted that Group 3 (G3) MB, which has a poor five-year survival, would be sensitive to triptolide/Minnelide. We subsequently showed that both triptolide and Minnelide attenuate the viability of G3 MB cells ex vivo. Transcriptomic analyses identified MYC signaling, a pathologically relevant driver of G3 MB, as a downstream target of this class of drugs. We validated this MYC dependency in G3 MB cells and showed that triptolide exerts its efficacy by reducing both MYC transcription and MYC protein stability. Importantly, Minnelide acted on MYC to reduce tumor growth and leptomeningeal spread, which resulted in improved survival of G3 MB animal models. Moreover, Minnelide improved the efficacy of adjuvant chemotherapy, further highlighting its potential for the treatment of MYC-driven G3 MB patients.

2.
bioRxiv ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38853982

RESUMO

Background: Pancreatic ductal adenocarcinoma (PDAC) is the most common form of pancreatic cancer. PDAC's poor prognosis and resistance to immunotherapy are attributed in part to its dense, fibrotic tumor microenvironment (TME), which is known to inhibit immune cell infiltration. We recently demonstrated that PDAC patients with higher natural killer (NK) cell content and activation have better survival rates. However, NK cell interactions in the PDAC TME have yet to be deeply studied. We show here that NK cells are present and active in the human PDAC TME. Methods: We used imaging mass cytometry (IMC) to assess NK cell content, function, and spatial localization in human PDAC samples. Then, we used CellChat, a tool to infer ligand-receptor interactions, on a human PDAC scRNAseq dataset to further define NK cell interactions in PDAC. Results: Spatial analyses showed for the first time that active NK cells are present in the PDAC TME, and both associate and interact with malignant epithelial cell ducts. We also found that fibroblast-rich, desmoplastic regions limit NK cell infiltration in the PDAC TME. CellChat analysis identified that the CD44 receptor on NK cells interacts with PDAC extracellular matrix (ECM) components such as collagen, fibronectin and laminin expressed by fibroblasts and malignant epithelial cells. This led us to hypothesize that these interactions play roles in regulating NK cell motility in desmoplastic PDAC TMEs. Using 2D and 3D in vitro assays, we found that CD44 neutralization significantly increased NK cell invasion through matrix. Conclusions: Targeting ECM-immune cell interactions may increase NK cell invasion into the PDAC TME.

3.
Biol Open ; 13(7)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38912559

RESUMO

Changes in mitochondrial distribution are a feature of numerous age-related neurodegenerative diseases. In Drosophila, reducing the activity of Cdk5 causes a neurodegenerative phenotype and is known to affect several mitochondrial properties. Therefore, we investigated whether alterations of mitochondrial distribution are involved in Cdk5-associated neurodegeneration. We find that reducing Cdk5 activity does not alter the balance of mitochondrial localization to the somatodendritic versus axonal neuronal compartments of the mushroom body, the learning and memory center of the Drosophila brain. We do, however, observe changes in mitochondrial distribution at the axon initial segment (AIS), a neuronal compartment located in the proximal axon involved in neuronal polarization and action potential initiation. Specifically, we observe that mitochondria are partially excluded from the AIS in wild-type neurons, but that this exclusion is lost upon reduction of Cdk5 activity, concomitant with the shrinkage of the AIS domain that is known to occur in this condition. This mitochondrial redistribution into the AIS is not likely due to the shortening of the AIS domain itself but rather due to altered Cdk5 activity. Furthermore, mitochondrial redistribution into the AIS is unlikely to be an early driver of neurodegeneration in the context of reduced Cdk5 activity.


Assuntos
Axônios , Quinase 5 Dependente de Ciclina , Mitocôndrias , Animais , Mitocôndrias/metabolismo , Quinase 5 Dependente de Ciclina/metabolismo , Quinase 5 Dependente de Ciclina/genética , Axônios/metabolismo , Drosophila , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Modelos Animais de Doenças , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/metabolismo , Segmento Inicial do Axônio/metabolismo , Corpos Pedunculados/metabolismo , Degeneração Neural , Neurônios/metabolismo , Drosophila melanogaster/metabolismo
4.
J Biol Chem ; 300(6): 107341, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705393

RESUMO

Inactivating mutations of genes encoding the cohesin complex are common in a wide range of human cancers. STAG2 is the most commonly mutated subunit. Here we report the impact of stable correction of endogenous, naturally occurring STAG2 mutations on gene expression, 3D genome organization, chromatin loops, and Polycomb signaling in glioblastoma multiforme (GBM). In two GBM cell lines, correction of their STAG2 mutations significantly altered the expression of ∼10% of all expressed genes. Virtually all the most highly regulated genes were negatively regulated by STAG2 (i.e., expressed higher in STAG2-mutant cells), and one of them-HEPH-was regulated by STAG2 in uncultured GBM tumors as well. While STAG2 correction had little effect on large-scale features of 3D genome organization (A/B compartments, TADs), STAG2 correction did alter thousands of individual chromatin loops, some of which controlled the expression of adjacent genes. Loops specific to STAG2-mutant cells, which were regulated by STAG1-containing cohesin complexes, were very large, supporting prior findings that STAG1-containing cohesin complexes have greater loop extrusion processivity than STAG2-containing cohesin complexes and suggesting that long loops may be a general feature of STAG2-mutant cancers. Finally, STAG2 mutation activated Polycomb activity leading to increased H3K27me3 marks, identifying Polycomb signaling as a potential target for therapeutic intervention in STAG2-mutant GBM tumors. Together, these findings illuminate the landscape of STAG2-regulated genes, A/B compartments, chromatin loops, and pathways in GBM, providing important clues into the largely still unknown mechanism of STAG2 tumor suppression.


Assuntos
Proteínas de Ciclo Celular , Cromatina , Regulação Neoplásica da Expressão Gênica , Glioblastoma , Mutação , Proteínas do Grupo Polycomb , Transdução de Sinais , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Cromatina/metabolismo , Cromatina/genética , Proteínas do Grupo Polycomb/metabolismo , Proteínas do Grupo Polycomb/genética , Linhagem Celular Tumoral , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Genoma Humano , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Coesinas
5.
bioRxiv ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38585927

RESUMO

Reactive oxygen species (ROS) are associated with aging and neurodegeneration, but the significance of this association remains obscure. Here, using a Drosophila model of age-related neurodegeneration, we probe this relationship in the pathologically relevant tissue, the brain, by quantifying three specific mitochondrial ROS and manipulating these redox species pharmacologically. Our goal is to ask whether pathology-associated changes in redox state are detrimental for survival, whether they may be beneficial responses, or whether they are simply covariates of pathology that do not alter viability. We find, surprisingly, that increasing mitochondrial H2O2 correlates with improved survival. We also find evidence that drugs that alter the mitochondrial glutathione redox potential modulate survival primarily through the compensatory effects they induce rather than through their direct effects on the final mitochondrial glutathione redox potential per se. We also find that the response to treatment with a redox-altering drug varies dramatically depending on the age at which the drug is administered, the duration of the treatment, and the genotype of the individual receiving the drug. These data have important implications for the design and interpretation of studies investigating the effect of redox state on health and disease as well as on efforts to modify the redox state to achieve therapeutic goals.

6.
bioRxiv ; 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38405730

RESUMO

Changes in mitochondrial distribution are a feature of numerous age-related neurodegenerative diseases. In Drosophila, reducing the activity of Cdk5 causes a neurodegenerative phenotype and is known to affect several mitochondrial properties. Therefore, we investigated whether alterations of mitochondrial distribution are involved in Cdk5-associated neurodegeneration. We find that reducing Cdk5 activity does not alter the balance of mitochondrial localization to the somatodendritic vs. axonal neuronal compartments of the mushroom body, the learning and memory center of the Drosophila brain. We do, however, observe changes in mitochondrial distribution at the axon initial segment (AIS), a neuronal compartment located in the proximal axon involved in neuronal polarization and action potential initiation. Specifically, we observe that mitochondria are partially excluded from the AIS in wild-type neurons, but that this exclusion is lost upon reduction of Cdk5 activity, concomitant with the shrinkage of the AIS domain that is known to occur in this condition. This mitochondrial redistribution into the AIS is not likely due to the shortening of the AIS domain itself but rather due to altered Cdk5 activity. Furthermore, mitochondrial redistribution into the AIS is unlikely to be an early driver of neurodegeneration in the context of reduced Cdk5 activity.

7.
Arch Pathol Lab Med ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38375737

RESUMO

CONTEXT.­: Biomarker reporting has increasingly become a key component of pathology reporting, providing diagnostic, prognostic, and actionable therapeutic data for patient care. OBJECTIVE.­: To expand and improve the College of American Pathologists (CAP) biomarker protocols. DESIGN.­: We surveyed CAP members to better understand the limitations they experienced when reporting cancer biomarker results. A Biomarker Workgroup reviewed the survey results and developed a strategy to improve and standardize biomarker reporting. Drafts of new and revised biomarker protocols were reviewed in both print and electronic template formats during interactive webinars presented to the CAP House of Delegates. Feedback was collected, and appropriate revisions were made to finalize the protocols. RESULTS.­: The first phase of the CAP Biomarker Workgroup saw the development of (1) a new stand-alone general Immunohistochemistry Biomarker Protocol that includes reporting for ER (estrogen receptor), PR (progesterone receptor), Ki-67, HER2 (human epidermal growth factor receptor 2), PD-L1 (programmed death ligand-1), and mismatch repair; (2) a new Head and Neck Biomarker Protocol that updates the prior 2017 paper-only version into an electronic template, adding new diagnostic and theranostic markers; (3) a major revision to the Lung Biomarker Protocol to streamline it and add in pan-cancer markers; and (4) a revision to the Colon and Rectum Biomarker Protocol to add HER2 reporting. CONCLUSIONS.­: We have taken a multipronged approach to improving biomarker reporting in the CAP cancer protocols. We continue to review current biomarker reporting protocols to reduce and eliminate unnecessary methodologic details and update with new markers as needed. The biomarker templates will serve as standardized modular units that can be inserted into cancer-reporting protocols.

8.
Dev Neurosci ; 45(6): 335-341, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37699369

RESUMO

Pediatric autoimmune neuropsychiatric disorder associated with streptococcal infections (PANDAS) is an acute onset or exacerbation of neuropsychiatric symptoms following a group A streptococcus infection. It is believed to be a result of autoimmune response to streptococcal infection, but there is insufficient evidence to fully support this theory. Although this disease is primarily thought to be a disease of childhood, it is reported to occur also in adults. PANDAS is a well-defined clinical entity, but the neuropathology of this condition has not been established yet. We describe the clinical course of a 26-year-old female diagnosed with PANDAS. She committed suicide and her brain was biobanked for further studies. We examined the banked tissue and performed special stains, immunohistochemical, and immunofluorescence analyses to characterize the neuropathology of this condition. Histology of the temporal lobes, hippocampus, and basal ganglia shows mild gliosis and Alzheimer's type II astrocytes. Acute hypoxic ischemic changes were noted in hippocampus CA1 and CA2 areas. Immunostaining shows increased parenchymal/perivascular GFAP staining and many vessels with mild increases in CD3-, CD4-, and CD25-stained lymphocytes in the basal ganglia. The findings suggest that CD4- and CD25-positive T cells might have an important role in understanding the neuroinflammation and pathogenesis of this condition. The case represents the first neuropathological evaluation report for PANDAS.


Assuntos
Doenças Autoimunes , Transtornos Mentais , Infecções Estreptocócicas , Humanos , Criança , Adulto Jovem , Feminino , Adulto , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/etiologia , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/complicações , Encéfalo
9.
Sci Rep ; 12(1): 17069, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36224354

RESUMO

Glioblastoma is a prevalent malignant brain tumor and despite clinical intervention, tumor recurrence is frequent and usually fatal. Genomic investigations have provided a greater understanding of molecular heterogeneity in glioblastoma, yet there are still no curative treatments, and the prognosis has remained unchanged. The aggressive nature of glioblastoma is attributed to the heterogeneity in tumor cell subpopulations and aberrant microvascular proliferation. Ganglioside-directed immunotherapy and membrane lipid therapy have shown efficacy in the treatment of glioblastoma. To truly harness these novel therapeutics and develop a regimen that improves clinical outcome, a greater understanding of the altered lipidomic profiles within the glioblastoma tumor microenvironment is urgently needed. In this work, high resolution mass spectrometry imaging was utilized to investigate lipid heterogeneity in human glioblastoma samples. Data presented offers the first insight into the histology-specific accumulation of lipids involved in cell metabolism and signaling. Cardiolipins, phosphatidylinositol, ceramide-1-phosphate, and gangliosides, including the glioblastoma stem cell marker, GD3, were shown to differentially accumulate in tumor and endothelial cell subpopulations. Conversely, a reduction in sphingomyelins and sulfatides were detected in tumor cell regions. Cellular accumulation for each lipid class was dependent upon their fatty acid residue composition, highlighting the importance of understanding lipid structure-function relationships. Discriminating ions were identified and correlated to histopathology and Ki67 proliferation index. These results identified multiple lipids within the glioblastoma microenvironment that warrant further investigation for the development of predictive biomarkers and lipid-based therapeutics.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/genética , Cardiolipinas , Ceramidas , Ácidos Graxos , Gangliosídeos/metabolismo , Glioblastoma/metabolismo , Humanos , Antígeno Ki-67 , Espectrometria de Massas , Recidiva Local de Neoplasia , Fosfatos , Fosfatidilinositóis , Esfingomielinas , Sulfoglicoesfingolipídeos , Microambiente Tumoral
10.
Front Mol Neurosci ; 15: 831116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35283733

RESUMO

Aging and age-related neurodegeneration are both associated with the accumulation of unfolded and abnormally folded proteins, highlighting the importance of protein homeostasis (termed proteostasis) in maintaining organismal health. To this end, two cellular compartments with essential protein folding functions, the endoplasmic reticulum (ER) and the mitochondria, are equipped with unique protein stress responses, known as the ER unfolded protein response (UPR ER ) and the mitochondrial UPR (UPR mt ), respectively. These organellar UPRs play roles in shaping the cellular responses to proteostatic stress that occurs in aging and age-related neurodegeneration. The loss of adaptive UPR ER and UPR mt signaling potency with age contributes to a feed-forward cycle of increasing protein stress and cellular dysfunction. Likewise, UPR ER and UPR mt signaling is often altered in age-related neurodegenerative diseases; however, whether these changes counteract or contribute to the disease pathology appears to be context dependent. Intriguingly, altering organellar UPR signaling in animal models can reduce the pathological consequences of aging and neurodegeneration which has prompted clinical investigations of UPR signaling modulators as therapeutics. Here, we review the physiology of both the UPR ER and the UPR mt , discuss how UPR ER and UPR mt signaling changes in the context of aging and neurodegeneration, and highlight therapeutic strategies targeting the UPR ER and UPR mt that may improve human health.

11.
Arch Pathol Lab Med ; 146(5): 547-574, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35175291

RESUMO

CONTEXT.­: The diagnosis and clinical management of patients with diffuse gliomas (DGs) have evolved rapidly over the past decade with the emergence of molecular biomarkers that are used to classify, stratify risk, and predict treatment response for optimal clinical care. OBJECTIVE.­: To develop evidence-based recommendations for informing molecular biomarker testing for pediatric and adult patients with DGs and provide guidance for appropriate laboratory test and biomarker selection for optimal diagnosis, risk stratification, and prediction. DESIGN.­: The College of American Pathologists convened an expert panel to perform a systematic review of the literature and develop recommendations. A systematic review of literature was conducted to address the overarching question, "What ancillary tests are needed to classify DGs and sufficiently inform the clinical management of patients?" Recommendations were derived from quality of evidence, open comment feedback, and expert panel consensus. RESULTS.­: Thirteen recommendations and 3 good practice statements were established to guide pathologists and treating physicians on the most appropriate methods and molecular biomarkers to include in laboratory testing to inform clinical management of patients with DGs. CONCLUSIONS.­: Evidence-based incorporation of laboratory results from molecular biomarker testing into integrated diagnoses of DGs provides reproducible and clinically meaningful information for patient management.


Assuntos
Glioma , Patologistas , Adulto , Criança , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Glioma/diagnóstico , Glioma/genética , Técnicas de Diagnóstico Molecular , Receptor ErbB-2/genética , Revisões Sistemáticas como Assunto
12.
J Transl Med ; 19(1): 480, 2021 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-34838031

RESUMO

BACKGROUND: The characterization of the immune component of the tumor microenvironment (TME) of human epidermal growth factor receptor 2 positive (HER2+) breast cancer has been limited. Molecular and spatial characterization of HER2+ TME of primary, recurrent, and metastatic breast tumors has the potential to identify immune mediated mechanisms and biomarker targets that could be used to guide selection of therapies. METHODS: We examined 15 specimens from eight patients with HER2+ breast cancer: 10 primary breast tumors (PBT), two soft tissue, one lung, and two brain metastases (BM). Using molecular profiling by bulk gene expression TME signatures, including the Tumor Inflammation Signature (TIS) and PAM50 subtyping, as well as spatial characterization of immune hot, warm, and cold regions in the stroma and tumor epithelium using 64 protein targets on the GeoMx Digital Spatial Profiler. RESULTS: PBT had higher infiltration of immune cells relative to metastatic sites and higher protein and gene expression of immune activation markers when compared to metastatic sites. TIS scores were lower in metastases, particularly in BM. BM also had less immune infiltration overall, but in the stromal compartment with the highest density of immune infiltration had similar levels of T cells that were less activated than PBT stromal regions suggesting immune exclusion in the tumor epithelium. CONCLUSIONS: Our findings show stromal and tumor localized immune cells in the TME are more active in primary versus metastatic disease. This suggests patients with early HER2+ breast cancer could have more benefit from immune-targeting therapies than patients with advanced disease.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/genética , Feminino , Humanos , Recidiva Local de Neoplasia , Proteômica , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Transcriptoma , Microambiente Tumoral
13.
Nature ; 599(7886): 673-678, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34732895

RESUMO

Immune exclusion predicts poor patient outcomes in multiple malignancies, including triple-negative breast cancer (TNBC)1. The extracellular matrix (ECM) contributes to immune exclusion2. However, strategies to reduce ECM abundance are largely ineffective or generate undesired outcomes3,4. Here we show that discoidin domain receptor 1 (DDR1), a collagen receptor with tyrosine kinase activity5, instigates immune exclusion by promoting collagen fibre alignment. Ablation of Ddr1 in tumours promotes the intratumoral penetration of T cells and obliterates tumour growth in mouse models of TNBC. Supporting this finding, in human TNBC the expression of DDR1 negatively correlates with the intratumoral abundance of anti-tumour T cells. The DDR1 extracellular domain (DDR1-ECD), but not its intracellular kinase domain, is required for immune exclusion. Membrane-untethered DDR1-ECD is sufficient to rescue the growth of Ddr1-knockout tumours in immunocompetent hosts. Mechanistically, the binding of DDR1-ECD to collagen enforces aligned collagen fibres and obstructs immune infiltration. ECD-neutralizing antibodies disrupt collagen fibre alignment, mitigate immune exclusion and inhibit tumour growth in immunocompetent hosts. Together, our findings identify a mechanism for immune exclusion and suggest an immunotherapeutic target for increasing immune accessibility through reconfiguration of the tumour ECM.


Assuntos
Colágeno/metabolismo , Receptor com Domínio Discoidina 1/metabolismo , Matriz Extracelular/metabolismo , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/metabolismo , Evasão Tumoral , Animais , Linhagem Celular Tumoral , Receptor com Domínio Discoidina 1/antagonistas & inibidores , Receptor com Domínio Discoidina 1/deficiência , Receptor com Domínio Discoidina 1/genética , Modelos Animais de Doenças , Matriz Extracelular/imunologia , Feminino , Deleção de Genes , Técnicas de Inativação de Genes , Humanos , Imunocompetência/imunologia , Imunoterapia , Camundongos , Linfócitos T/citologia , Linfócitos T/imunologia , Neoplasias de Mama Triplo Negativas/terapia
14.
Aging Cell ; 20(7): e13411, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34089289

RESUMO

Age-related loss of muscle mass and strength is widely attributed to limitation in the capacity of muscle resident satellite cells to perform their myogenic function. This idea contains two notions that have not been comprehensively evaluated by experiment. First, it entails the idea that we damage and lose substantial amounts of muscle in the course of our normal daily activities. Second, it suggests that mechanisms of muscle repair are in some way exhausted, thus limiting muscle regeneration. A third potential option is that the aged environment becomes inimical to the conduct of muscle regeneration. In the present study, we used our established model of human muscle xenografting to test whether muscle samples taken from cadavers, of a range of ages, maintained their myogenic potential after being transplanted into immunodeficient mice. We find no measurable difference in regeneration across the range of ages investigated up to 78 years of age. Moreover, we report that satellite cells maintained their myogenic capacity even when muscles were grafted 11 days postmortem in our model. We conclude that the loss of muscle mass with increasing age is not attributable to any intrinsic loss of myogenicity and is most likely a reflection of progressive and detrimental changes in the muscle microenvironment such as to disfavor the myogenic function of these cells.


Assuntos
Envelhecimento/fisiologia , Células Satélites de Músculo Esquelético/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Cell Cycle ; 20(8): 752-764, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33818291

RESUMO

Tau accumulation is a core component of Alzheimer's disease and other neurodegenerative tauopathies. While tau's impact on neurons is a major area of research, the effect of extracellular tau on astrocytes is largely unknown. This article summarizes our recent studies showing that astrocyte senescence plays a critical role in neurodegenerative diseases and integrates extracellular tau into the regulatory loop of senescent astrocyte-mediated neurotoxicity. Human astrocytes in vitro undergoing senescence were shown to acquire the inflammatory senescence-associated secretory phenotype (SASP) and toxicity to neurons, which may recapitulate aging- and disease-associated neurodegeneration. Here, we show that human astrocytes exposed to extracellular tau in vitro also undergo cellular senescence and acquire a neurotoxic SASP (e.g. IL-6 secretion), with oxidative stress response (indicated by upregulated NRF2 target genes) and a possible activation of inflammasome (indicated by upregulated ASC and IL-1ß). These findings suggest that senescent astrocytes induced by various conditions and insults, including tau exposure, may represent a therapeutic target to inhibit or delay the progression of neurodegenerative diseases. We also discuss the pathological activity of extracellular tau in microglia and astrocytes, the disease relevance and diversity of tau forms, therapeutics targeting senescence in neurodegeneration, and the roles of p53 and its isoforms in astrocyte-mediated neurotoxicity and neuroprotection.


Assuntos
Astrócitos/metabolismo , Senescência Celular/fisiologia , Doenças Neurodegenerativas/metabolismo , Fenótipo Secretor Associado à Senescência/fisiologia , Proteínas tau/toxicidade , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Humanos , Doenças Neurodegenerativas/induzido quimicamente , Doenças Neurodegenerativas/patologia , Fenótipo Secretor Associado à Senescência/efeitos dos fármacos
16.
Urol Oncol ; 39(7): 438.e1-438.e9, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33712344

RESUMO

OBJECTIVE: Improvements to bladder cancer risk stratification guidelines are needed to better tailor post-operative surveillance and adjuvant therapy to individual patients. We previously identified STAG2 as a commonly mutated tumor suppressor gene in bladder cancer and an independent predictor of progression in NMIBC. Here we test the value of combining STAG2 immunostaining with other risk stratification biomarkers in NMIBC, and as an individual biomarker in MIBC. MATERIALS AND METHODS: STAG2 immunohistochemistry was performed on a progressor-enriched cohort of tumors from 297 patients with NMIBC, and on tumors from 406 patients with MIBC from Aarhus University Hospital in Denmark. Survival analysis was performed using Kaplan-Meier survival analysis, the log rank test, and Cox proportional hazards models. RESULTS: STAG2-negative low-grade NMIBC tumors were 2.5 times less likely to progress to muscle invasion than STAG2-positive low-grade NMIBC tumors (Log-rank test, P = 0.008). In a composite group of patients with AUA intermediate and high-risk NMIBC tumors, STAG2-negative tumors were less likely to progress (Log-rank test, P = 0.02). In contrast to NMIBC, we show that STAG2 is not useful as a prognostic biomarker in MIBC. CONCLUSIONS: STAG2 immunostaining can be used to subdivide low-grade NMIBC tumors into two groups with substantially different risks of disease progression. Furthermore, STAG2 immunostaining may be useful to enhance NMIBC risk stratification guidelines, though larger cohorts are needed to solidify this conclusion in individual risk groups. STAG2 is not useful as a biomarker in MIBC. Further study of the use of STAG2 immunostaining as a biomarker for predicting the clinical behavior in NMIBC is warranted.


Assuntos
Biomarcadores Tumorais/análise , Proteínas de Ciclo Celular/análise , Neoplasias da Bexiga Urinária/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Prognóstico , Estudos Retrospectivos , Medição de Risco , Análise de Sobrevida , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
17.
Int J Mol Sci ; 22(4)2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33567524

RESUMO

Alzheimer's disease is a chronic neurodegenerative disorder and represents the main cause of dementia globally. Currently, the world is suffering from the coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a virus that uses angiotensin-converting enzyme 2 (ACE2) as a receptor to enter the host cells. In COVID-19, neurological manifestations have been reported to occur. The present study demonstrates that the protein expression level of ACE2 is upregulated in the brain of patients with Alzheimer's disease. The increased ACE2 expression is not age-dependent, suggesting the direct relationship between Alzheimer's disease and ACE2 expression. Oxidative stress has been implicated in the pathogenesis of Alzheimer's disease, and brains with the disease examined in this study also exhibited higher carbonylated proteins, as well as an increased thiol oxidation state of peroxiredoxin 6 (Prx6). A moderate positive correlation was found between the increased ACE2 protein expression and oxidative stress in brains with Alzheimer's disease. In summary, the present study reveals the relationships between Alzheimer's disease and ACE2, the receptor for SARS-CoV-2. These results suggest the importance of carefully monitoring patients with both Alzheimer's disease and COVID-19 in order to identify higher viral loads in the brain and long-term adverse neurological consequences.


Assuntos
Doença de Alzheimer/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/epidemiologia , COVID-19/metabolismo , Hipocampo/metabolismo , Pandemias , Receptores Virais/metabolismo , SARS-CoV-2/metabolismo , Regulação para Cima , Doença de Alzheimer/complicações , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Autopsia , COVID-19/complicações , COVID-19/virologia , Hipocampo/patologia , Humanos , Oxirredução , Estresse Oxidativo , Peroxirredoxina VI/metabolismo , Placa Amiloide/metabolismo , Carbonilação Proteica , Índice de Gravidade de Doença , Internalização do Vírus
18.
Neuropsychopharmacology ; 46(7): 1364-1372, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33558674

RESUMO

Despite strong evidence of heritability and growing discovery of genetic markers for major mental illness, little is known about how gene expression in the brain differs across psychiatric diagnoses, or how known genetic risk factors shape these differences. Here we investigate expressed genes and gene transcripts in postmortem subgenual anterior cingulate cortex (sgACC), a key component of limbic circuits linked to mental illness. RNA obtained postmortem from 200 donors diagnosed with bipolar disorder, schizophrenia, major depression, or no psychiatric disorder was deeply sequenced to quantify expression of over 85,000 gene transcripts, many of which were rare. Case-control comparisons detected modest expression differences that were correlated across disorders. Case-case comparisons revealed greater expression differences, with some transcripts showing opposing patterns of expression between diagnostic groups, relative to controls. The ~250 rare transcripts that were differentially-expressed in one or more disorder groups were enriched for genes involved in synapse formation, cell junctions, and heterotrimeric G-protein complexes. Common genetic variants were associated with transcript expression (eQTL) or relative abundance of alternatively spliced transcripts (sQTL). Common genetic variants previously associated with disease risk were especially enriched for sQTLs, which together accounted for disproportionate fractions of diagnosis-specific heritability. Genetic risk factors that shape the brain transcriptome may contribute to diagnostic differences between broad classes of mental illness.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Transtorno Bipolar/genética , Transtorno Depressivo Maior/genética , Giro do Cíngulo , Humanos , RNA , Transcriptoma
19.
Ann Otol Rhinol Laryngol ; 130(2): 215-218, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32659110

RESUMO

OBJECTIVES: To present a novel location in which neurosarcoidomatous inflammation is identified and its accompanying presentation. METHODS: The authors present a case of bilateral vocal fold paresis associated with non-caseating granulomatous inflammation of the cervical and intra-axial portions of the vagus nerve masquerading as a cranial nerve tumor. RESULTS: Examination revealed bilateral vocal fold paresis and asymmetric palate elevation. MRI demonstrated enhancing bilateral jugular foramen masses, and neck ultrasound demonstrated bilateral thickened appearance of the vagus nerves. Vagus nerve biopsy demonstrated non-caseating granulomas. CONCLUSIONS: Neurosarcoidosis may contribute to variable cranial neuropathies. Vocal fold paresis is usually thought to arise from mediastinal compression of the left recurrent laryngeal nerve. Rarely, though, lesions may arise in other parts of the vagus nerve. Failure of response to steroids does not rule out the diagnosis, making tissue diagnosis important in some cases.


Assuntos
Doenças do Sistema Nervoso Central/diagnóstico , Sarcoidose/diagnóstico , Nervo Vago/diagnóstico por imagem , Nervo Vago/patologia , Paralisia das Pregas Vocais/etiologia , Biópsia , Feminino , Granuloma/diagnóstico por imagem , Granuloma/etiologia , Humanos , Forâmen Jugular/diagnóstico por imagem , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Ultrassonografia
20.
bioRxiv ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33052346

RESUMO

Alzheimer's disease is a chronic neurodegenerative disorder and represents the main cause of dementia. Currently, the world is suffering from the pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that uses angiotensin-converting enzyme 2 (ACE2) as a receptor to enter the host cells. In COVID-19, neurological manifestations have been reported to occur. The present study demonstrates that the protein expression level of ACE2 is upregulated in the brain of Alzheimer's disease patients. The increased ACE2 expression is not age-dependent, suggesting the direct relationship between Alzheimer's disease and the ACE2 expression. Oxidative stress has been implicated in the pathogenesis of Alzheimer's disease, and Alzheimer's disease brains examined in this study also exhibited higher carbonylated proteins as well as increased thiol oxidation state of peroxiredoxin 6 (Prx6). The positive correlation was found between the increased ACE2 protein expression and oxidative stress in Alzheimer's disease brain. Thus, the present study reveals the relationships between Alzheimer's disease and ACE2, the receptor for SARS-CoV-2. These results warrant monitoring Alzheimer's disease patients with COVID-19 carefully for the possible higher viral load in the brain and long-term adverse neurological consequences.

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