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1.
BMC Cancer ; 24(1): 199, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38347462

RESUMO

BACKGROUND: Glioblastoma (GBM) is an aggressive brain tumor that exhibits resistance to current treatment, making the identification of novel therapeutic targets essential. In this context, cellular prion protein (PrPC) stands out as a potential candidate for new therapies. Encoded by the PRNP gene, PrPC can present increased expression levels in GBM, impacting cell proliferation, growth, migration, invasion and stemness. Nevertheless, the exact molecular mechanisms through which PRNP/PrPC modulates key aspects of GBM biology remain elusive. METHODS: To elucidate the implications of PRNP/PrPC in the biology of this cancer, we analyzed publicly available RNA sequencing (RNA-seq) data of patient-derived GBMs from four independent studies. First, we ranked samples profiled by bulk RNA-seq as PRNPhigh and PRNPlow and compared their transcriptomic landscape. Then, we analyzed PRNP+ and PRNP- GBM cells profiled by single-cell RNA-seq to further understand the molecular context within which PRNP/PrPC might function in this tumor. We explored an additional proteomics dataset, applying similar comparative approaches, to corroborate our findings. RESULTS: Functional profiling revealed that vesicular dynamics signatures are strongly correlated with PRNP/PrPC levels in GBM. We found a panel of 73 genes, enriched in vesicle-related pathways, whose expression levels are increased in PRNPhigh/PRNP+ cells across all RNA-seq datasets. Vesicle-associated genes, ANXA1, RAB31, DSTN and SYPL1, were found to be upregulated in vitro in an in-house collection of patient-derived GBM. Moreover, proteome analysis of patient-derived samples reinforces the findings of enhanced vesicle biogenesis, processing and trafficking in PRNPhigh/PRNP+ GBM cells. CONCLUSIONS: Together, our findings shed light on a novel role for PrPC as a potential modulator of vesicle biology in GBM, which is pivotal for intercellular communication and cancer maintenance. We also introduce GBMdiscovery, a novel user-friendly tool that allows the investigation of specific genes in GBM biology.


Assuntos
Glioblastoma , Príons , Humanos , Expressão Gênica , Perfilação da Expressão Gênica , Glioblastoma/genética , Glioblastoma/patologia , Proteínas Priônicas/genética , Proteínas Priônicas/metabolismo , Príons/genética , Príons/metabolismo , Proteínas rab de Ligação ao GTP/genética , Sinaptofisina/metabolismo
2.
Semin Cell Dev Biol ; 133: 32-41, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-35697594

RESUMO

Extracellular vesicles (EVs) are membrane-delimited vesicular bodies carrying different molecules, classified according to their size, density, cargo, and origin. Research on this topic has been actively growing through the years, as EVs are associated with critical pathological processes such as neurodegenerative diseases and cancer. Despite that, studies exploring the physiological functions of EVs are sparse, with particular emphasis on their role in organismal development, initial cell differentiation, and morphogenesis. In this review, we explore the topic of EVs from a developmental perspective, discussing their role in the earliest cell-fate decisions and neural tissue morphogenesis. We focus on the function of EVs through development to highlight possible conserved or novel processes that can impact disease progression. Specifically, we take advantage of what was learned about their role in development so far to discuss EVs impact on glioblastoma, a particular brain tumor of stem-cell origin and poor prognosis, and how their function can be hijacked to improve current therapies.


Assuntos
Vesículas Extracelulares , Glioblastoma , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Vesículas Extracelulares/patologia , Comunicação Celular , Células-Tronco , Diferenciação Celular
3.
Saúde Redes ; 7(Supl. 2): 73-82, 20211201.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1367117

RESUMO

A Atenção Primária à Saúde apresenta-se como um setor de destaque para ações de Educação em Saúde, sobretudo nos momentos de sala de espera. O presente escrito trata-se de um relato de experiência que objetiva problematizar os momentos de Educação em Saúde nas salas de espera como espaços de produção de cuidado e trabalho interprofissional. As ações ocorreram em duas Unidades de Saúde da Família da cidade de Barreira, Bahia, no período de 1 ano com os acadêmicos dos cursos da saúde vinculados ao Programa de Educação para o Trabalho em Saúde Interprofissionalidade da Universidade Federal do Oeste da Bahia. A partir do diálogo dos discentes do programa com a equipe das unidades participantes, definiram-se temas que abordaram saúde da mulher e do homem, doenças crônicas, saúde mental, hábitos de vida, planejamento familiar, entre outros. Foram utilizadas metodologias como encenações teatrais, dinâmicas e rodas de conversa. Essas atividades não só possibilitaram encontros de saberes como também transformações na maneira de pensar a formação e o aprendizado. Percebeu-se que as atividades de extensão passaram a cumprir seu papel político em interface com o ensino e a pesquisa. Um dos grandes desafios enfrentados nas ações foi o compromisso com uma abordagem integral do sujeito. A Educação em Saúde, nas salas de espera, pode ser consolidada como uma prática de produção de cuidado em saúde. Por intermédio dela, é possível fornecer um cuidado territorializado, estimulando o trabalho interprofissional e a participação social.

4.
Clinics (Sao Paulo) ; 76: e2902, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34614112

RESUMO

OBJECTIVES: To investigate the expression levels of surface markers of activation (CD38 and HLA-DR), inhibition (PD-1, TIGIT and CD57) and co-stimulation (CD28 and CD127) on CD4+ T cells of children/adolescents with vertical HIV infection (HI patients) and HIV-uninfected (HU) controls vaccinated with the meningococcal C conjugate vaccine (MCC). METHODS: HI patients (n=12), aged 8-17 years, were immunized with two MCC injections, while HU controls (n=9), aged 5.3-10.7 years, received a single MCC dose (as per national recommendation at the time of this study, a single MCC vaccine dose should be given for healthy children and youth aged 1-18 years). The HI patients were categorized according to the combined antiretroviral therapy (cART) treatment. Blood samples were obtained before vaccination, after priming, and after the administration of a booster dose of vaccine to determine the serum bactericidal antibody (SBA) titers and the expression levels of surface markers on CD4+ T cells by flow cytometry. The levels of serum cytokines, IL-4 and CXCL-13 were also measured using Luminex kits. RESULTS: The co-expression of the TIGIT-HLA-DR-CD38 molecules increased in the CD4+ T cells of HI patients/no-cART who also showed a lower frequency of CD127+CD28+ CD4+ T cells than HI patients/cART and HU group subjects. There were significant negative correlations between the frequency of exhausted CD4+ T cells and the SBA response. IL-4 levels were higher in HI patients/cART and positively correlated with SBA titers but negatively associated with the expression of exhaustion markers. Moreover, the CXCL-13 levels were positively correlated with the exhausted CD4+ T cells. CONCLUSION: The results of our study suggest that the co-expression of exhaustion markers and/or loss of co-stimulatory molecules influence the SBA response in HI patients.


Assuntos
Infecções por HIV , Vacinas Meningocócicas , Adolescente , Formação de Anticorpos , Linfócitos T CD4-Positivos , Criança , Humanos
5.
Endocr Connect ; 10(7): 707-714, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34077391

RESUMO

BACKGROUND: Thyroid nodules diagnosed as 'atypia of undetermined significance/follicular lesion of undetermined significance' (AUS/FLUS) or 'follicular neoplasm/suspected follicular neoplasm' (FN/SFN), according to Bethesda's classification, represent a challenge in clinical practice. Computerized analysis of nuclear images (CANI) could be a useful tool for these cases. Our aim was to evaluate the ability of CANI to correctly classify AUS/FLUS and FN/SFN thyroid nodules for malignancy. METHODS: We studied 101 nodules cytologically classified as AUS/FLUS (n = 68) or FN/SFN (n = 33) from 97 thyroidectomy patients. Slides with cytological material were submitted for manual selection and analysis of the follicular cell nuclei for morphometric and texture parameters using ImageJ software. The histologically benign and malignant lesions were compared for such parameters which were then evaluated for the capacity to predict malignancy using the classification and regression trees gini model. The intraclass coefficient of correlation was used to evaluate method reproducibility. RESULTS: In AUS/FLUS nodule analysis, the benign and malignant nodules differed for entropy (P < 0.05), while the FN/SFN nodules differed for fractal analysis, coefficient of variation (CV) of roughness, and CV-entropy (P < 0.05). Considering the AUS/FLUS and FN/SFN nodules separately, it correctly classified 90.0 and 100.0% malignant nodules, with a correct global classification of 94.1 and 97%, respectively. We observed that reproducibility was substantially or nearly complete (0.61-0.93) in 10 of the 12 nuclear parameters evaluated. CONCLUSION: CANI demonstrated a high capacity for correctly classifying AUS/FLUS and FN/SFN thyroid nodules for malignancy. This could be a useful method to help increase diagnostic accuracy in the indeterminate thyroid cytology.

6.
Arch Endocrinol Metab ; 64(5): 630-635, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34033305

RESUMO

OBJECTIVE: Follicular lesions of the thyroid with papillary carcinoma nuclear characteristics are classified as infiltrative follicular variant of papillary thyroid carcinoma-FVPTC (IFVPTC), encapsulated/well demarcated FVPTC with tumour capsular invasion (IEFVPTC), and the newly described category "non-invasive follicular thyroid neoplasm with papillary-like nuclear features" (NIFTP) formerly known as non-invasive encapsulated FVPTC. This study evaluated whether computerized image analysis can detect nuclear differences between these three tumour subtypes. METHODS: Slides with histological material from 15 cases of NIFTP and 33 cases of FVPTC subtypes (22 IEFVPTC, and 11 IFVPTC) were analyzed using the Image J image processing program. Tumour cells were compared for both nuclear morphometry and chromatin textural characteristics. RESULTS: Nuclei from NIFTP and IFVPTC tumours differed in terms of chromatin textural features (grey intensity): mean (92.37 ± 21.01 vs 72.99 ± 14.73, p = 0.02), median (84.93 ± 21.17 vs 65.18 ± 17.08, p = 0.02), standard deviation (47.77 ± 9.55 vs 39.39 ± 7.18; p = 0.02), and coefficient of variation of standard deviation (19.96 ± 4.01 vs 24.75 ± 3.31; p = 0.003). No differences were found in relation to IEFVPTC. CONCLUSION: Computerized image analysis revealed differences in nuclear texture between NIFTP and IFVPTC, but not for IEFVPTC.


Assuntos
Adenocarcinoma Folicular , Carcinoma Papilar, Variante Folicular , Carcinoma Papilar , Neoplasias da Glândula Tireoide , Adenocarcinoma Folicular/diagnóstico por imagem , Adenocarcinoma Folicular/genética , Cromatina , Humanos , Estudos Retrospectivos , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/genética
7.
Dent Mater ; 37(5): 863-874, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33648745

RESUMO

OBJECTIVE: The aim of this study was to evaluate the influence of the incorporation of chlorhexidine-hexametaphosphate nanoparticles (CHX-HMP NPs) on antibacterial, cytotoxic and physicochemical properties of AH Plus (AH), MTA Fillapex (MTA) and Pulp Canal Sealer (PCS). METHODS: The NPs were synthesized and characterized by Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), zeta potential, Atomic Force Microscopy (AFM) and Energy-Dispersive X-ray Spectroscopy (EDS). The incorporation was made by weight, 2% and 5% of NPs. The antimicrobial activity, cytotoxicity, flow, radiopacity, setting time, solubility and pH were evaluated. The statistical analysis was performed by two-way analysis of variance test and Tukey post hoc test (P < 0.05). RESULTS: SEM analysis showed the tendency for CHX-HMP NPs to cluster, the effective mean diameter measured by DLS: 169.39 nm and the zeta potential: -10.18 mV. The NPs were individually measured by AFM: 22.99-52.75 nm. EDS analysis identified the presence of C, N, O, Na, P, Cl. After incorporation: The Direct Contact Test showed an increase in the antimicrobial action of AH, PCS and MTA; the sealers showed a decrease in flow and at 24 h of immersion also an increase in solubility, but did not affect the radiopacity of the samples; AH setting time increased and MTA did not reach setting under any of the conditions tested. All samples showed a decrease in pH value as the immersion time progressed. SIGNIFICANCE: The incorporation of NPs can improve the antimicrobial performance of endodontic sealers without impairing other biological and physicochemical properties.


Assuntos
Nanopartículas , Materiais Restauradores do Canal Radicular , Antibacterianos/farmacologia , Compostos de Cálcio , Clorexidina/farmacologia , Cavidade Pulpar , Combinação de Medicamentos , Resinas Epóxi , Teste de Materiais , Fosfatos , Silicatos
8.
Mol Cell Biochem ; 476(2): 649-661, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33073314

RESUMO

The phytoalexin Resveratrol (3,5,4'-trihydroxystilbene; RSV) has been related to numerous beneficial effects on health by its cytoprotection and chemoprevention activities. Liver fibrosis is characterized by the extracellular matrix accumulation after hepatic injury and can lead to cirrhosis. Hepatic stellate cells (HSC) play a crucial role during fibrogenesis and liver wound healing by changing their quiescent phenotype to an activated phenotype for protecting healthy areas from damaged areas. Strategies on promoting the activated HSC death, the quiescence return or the cellular activation stimuli decrease play an important role on reducing liver fibrosis. Here, we evaluated the RSV effects on some markers of activation in GRX, an HSC model. We further evaluated the RSV influence in the ability of GRX on releasing inflammatory mediators. RSV at 1 and 10 µM did not alter the protein content of α-SMA, collagen I and GFAP; but 50 µM increased the content of these activation-related proteins. Also, RSV did not change the myofibroblast-like morphology of GRX. Interestingly, RSV at 10 and 50 µM decreased the GRX migration and collagen-I gel contraction. Finally, we showed that RSV triggered the increase in the TNF-α and IL-10 content in culture media of GRX while the opposite occurred for the IL-6 content. Altogether, these results suggested that RSV did not decrease the activation state of GRX and oppositely, triggered a pro-activation effect at the 50 µM concentration. However, despite the increase of TNF- α in culture media, these results on IL-6 and IL-10 secretion were in accordance with the anti-inflammatory role of RSV in our model.


Assuntos
Antioxidantes/farmacologia , Citocinas/metabolismo , Células Estreladas do Fígado/efeitos dos fármacos , Inflamação/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Resveratrol/farmacologia , Animais , Linhagem Celular , Proliferação de Células , Células Estreladas do Fígado/imunologia , Células Estreladas do Fígado/metabolismo , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Cirrose Hepática/imunologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Camundongos , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo
9.
Clinics ; 76: e2902, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1339713

RESUMO

OBJECTIVES: To investigate the expression levels of surface markers of activation (CD38 and HLA-DR), inhibition (PD-1, TIGIT and CD57) and co-stimulation (CD28 and CD127) on CD4+ T cells of children/adolescents with vertical HIV infection (HI patients) and HIV-uninfected (HU) controls vaccinated with the meningococcal C conjugate vaccine (MCC). METHODS: HI patients (n=12), aged 8-17 years, were immunized with two MCC injections, while HU controls (n=9), aged 5.3-10.7 years, received a single MCC dose (as per national recommendation at the time of this study, a single MCC vaccine dose should be given for healthy children and youth aged 1-18 years). The HI patients were categorized according to the combined antiretroviral therapy (cART) treatment. Blood samples were obtained before vaccination, after priming, and after the administration of a booster dose of vaccine to determine the serum bactericidal antibody (SBA) titers and the expression levels of surface markers on CD4+ T cells by flow cytometry. The levels of serum cytokines, IL-4 and CXCL-13 were also measured using Luminex kits. RESULTS: The co-expression of the TIGIT-HLA-DR-CD38 molecules increased in the CD4+ T cells of HI patients/no-cART who also showed a lower frequency of CD127+CD28+ CD4+ T cells than HI patients/cART and HU group subjects. There were significant negative correlations between the frequency of exhausted CD4+ T cells and the SBA response. IL-4 levels were higher in HI patients/cART and positively correlated with SBA titers but negatively associated with the expression of exhaustion markers. Moreover, the CXCL-13 levels were positively correlated with the exhausted CD4+ T cells. CONCLUSION: The results of our study suggest that the co-expression of exhaustion markers and/or loss of co-stimulatory molecules influence the SBA response in HI patients.


Assuntos
Humanos , Criança , Adolescente , Infecções por HIV , Vacinas Meningocócicas , Linfócitos T CD4-Positivos , Formação de Anticorpos
10.
Front Oncol ; 10: 597743, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33312955

RESUMO

Tumor cells can employ epithelial-mesenchymal transition (EMT) or autophagy in reaction to microenvironmental stress. Importantly, EMT and autophagy negatively regulate each other, are able to interconvert, and both have been shown to contribute to drug-resistance in glioblastoma (GBM). EMT has been considered one of the mechanisms that confer invasive properties to GBM cells. Autophagy, on the other hand, may show dual roles as either a GBM-promoter or GBM-suppressor, depending on microenvironmental cues. The Wingless (WNT) signaling pathway regulates a plethora of developmental and biological processes such as cellular proliferation, adhesion and motility. As such, GBM demonstrates deregulation of WNT signaling in favor of tumor initiation, proliferation and invasion. In EMT, WNT signaling promotes induction and stabilization of different EMT activators. WNT activity also represses autophagy, while nutrient deprivation induces ß-catenin degradation via autophagic machinery. Due to the importance of the WNT pathway to GBM, and the role of WNT signaling in EMT and autophagy, in this review we highlight the effects of the WNT signaling in the regulation of both processes in GBM, and discuss how the crosstalk between EMT and autophagy may ultimately affect tumor biology.

11.
Int J Mol Sci ; 21(20)2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33092231

RESUMO

The mobility of cellular prion protein (PrPC) in specific cell membrane domains and among distinct cell compartments dictates its molecular interactions and directs its cell function. PrPC works in concert with several partners to organize signaling platforms implicated in various cellular processes. The scaffold property of PrPC is able to gather a molecular repertoire to create heterogeneous membrane domains that favor endocytic events. Dynamic trafficking of PrPC through multiple pathways, in a well-orchestrated mechanism of intra and extracellular vesicular transport, defines its functional plasticity, and also assists the conversion and spreading of its infectious isoform associated with neurodegenerative diseases. In this review, we highlight how PrPC traffics across intra- and extracellular compartments and the consequences of this dynamic transport in governing cell functions and contributing to prion disease pathogenesis.


Assuntos
Doenças Neurodegenerativas/metabolismo , Proteínas PrPC/metabolismo , Doenças Priônicas/metabolismo , Transdução de Sinais , Animais , Membrana Celular/metabolismo , Humanos , Microdomínios da Membrana/metabolismo , Modelos Biológicos , Transporte Proteico
12.
Int J Mol Sci ; 21(18)2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32932634

RESUMO

Cell motility is a central process involved in fundamental biological phenomena during embryonic development, wound healing, immune surveillance, and cancer spreading. Cell movement is complex and dynamic and requires the coordinated activity of cytoskeletal, membrane, adhesion and extracellular proteins. Cellular prion protein (PrPC) has been implicated in distinct aspects of cell motility, including axonal growth, transendothelial migration, epithelial-mesenchymal transition, formation of lamellipodia, and tumor migration and invasion. The preferential location of PrPC on cell membrane favors its function as a pivotal molecule in cell motile phenotype, being able to serve as a scaffold protein for extracellular matrix proteins, cell surface receptors, and cytoskeletal multiprotein complexes to modulate their activities in cellular movement. Evidence points to PrPC mediating interactions of multiple key elements of cell motility at the intra- and extracellular levels, such as integrins and matrix proteins, also regulating cell adhesion molecule stability and cell adhesion cytoskeleton dynamics. Understanding the molecular mechanisms that govern cell motility is critical for tissue homeostasis, since uncontrolled cell movement results in pathological conditions such as developmental diseases and tumor dissemination. In this review, we discuss the relevant contribution of PrPC in several aspects of cell motility, unveiling new insights into both PrPC function and mechanism in a multifaceted manner either in physiological or pathological contexts.


Assuntos
Movimento Celular/fisiologia , Proteínas Priônicas/metabolismo , Animais , Adesão Celular/fisiologia , Membrana Celular/metabolismo , Membrana Celular/fisiologia , Citoesqueleto/metabolismo , Citoesqueleto/fisiologia , Humanos
13.
Phytother Res ; 34(4): 796-807, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31795012

RESUMO

Alzheimer's disease is a neurodegenerative disorder characterized by extracellular deposition of amyloid-ß (Aß) peptide and hyperphosphorylation of Tau protein, which ultimately leads to the formation of intracellular neurofibrillary tangles and cell death. Increasing evidence indicates that genistein, a soy isoflavone, has neuroprotective effects against Aß-induced toxicity. However, the molecular mechanisms involved in its neuroprotection are not well understood. In this study, we have established a neuronal damage model using retinoic-acid differentiated SH-SY5Y cells treated with different concentrations of Aß25-35 to investigate the effect of genistein against Aß-induced cell death and the possible involvement of protein kinase B (PKB, also termed Akt), glycogen synthase kinase 3ß (GSK-3ß), and Tau as an underlying mechanism to this neuroprotection. Differentiated SH-SY5Y cells were pre-treated for 24 hr with genistein (1 and 10 nM) and exposed to Aß25-35 (25 µM), and we found that genistein partially inhibited Aß induced cell death, primarily apoptosis. Furthermore, the protective effect of genistein was associated with the inhibition of Aß-induced Akt inactivation and Tau hyperphosphorylation. These findings reinforce the neuroprotective effects of genistein against Aß toxicity and provide evidence that its mechanism may involve regulation of Akt and Tau proteins.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Genisteína/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Neurônios/fisiologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas tau/efeitos dos fármacos , Proteínas tau/metabolismo
14.
Int J Mol Sci ; 20(22)2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31752169

RESUMO

Heat shock proteins (HSPs) are evolutionary conserved proteins that work as molecular chaperones and perform broad and crucial roles in proteostasis, an important process to preserve the integrity of proteins in different cell types, in health and disease. Their function in cancer is an important aspect to be considered for a better understanding of disease development and progression. Glioblastoma (GBM) is the most frequent and lethal brain cancer, with no effective therapies. In recent years, HSPs have been considered as possible targets for GBM therapy due their importance in different mechanisms that govern GBM malignance. In this review, we address current evidence on the role of several HSPs in the biology of GBMs, and how these molecules have been considered in different treatments in the context of this disease, including their activities in glioblastoma stem-like cells (GSCs), a small subpopulation able to drive GBM growth. Additionally, we highlight recent works that approach other classes of chaperones, such as histone and mitochondrial chaperones, as important molecules for GBM aggressiveness. Herein, we provide new insights into how HSPs and their partners play pivotal roles in GBM biology and may open new therapeutic avenues for GBM based on proteostasis machinery.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Proteínas de Choque Térmico/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Proteínas de Choque Térmico/efeitos dos fármacos , Humanos , Terapia de Alvo Molecular
15.
Neuroscience ; 404: 314-325, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771511

RESUMO

Several studies have demonstrated the antitumor effect of doxazosin, an α1-adrenergic blocker, against glioma and breast, bladder and prostate cancers. Doxazosin is also being evaluated as a treatment for posttraumatic stress disorder (PTSD) and alcoholism, and α1-adrenergic blockers have been linked to neuroprotection in neurodegenerative disorders, such as Alzheimer's Disease (AD). Cancer and AD have an inverse relationship in many aspects, with several factors that contribute to apoptosis inhibition and proliferation being increased in cancers but decreased in AD. Neuroblastoma (NB) is a pediatric tumor derived from embryonic neural-crest cells, with an overall cure rate of 40%, despite aggressive treatment. Thus, due to the need of new therapeutic strategies against NB and neurodegenerative disorders and the inverse relationship between these diseases, we investigated whether doxazosin may serve as an antitumor and neuroprotective agent. We analyzed the drug's effects on undifferentiated and retinoic acid-differentiated SH-SY5Y human NB cells and on an in vitro model of organotypic hippocampal cultures exposed to amyloid-ß. Doxazosin showed antitumor effect on undifferentiated NB cells by induction of apoptosis, necrosis, cell cycle arrest and decrease of p-EGFRTyr1048 levels. On differentiated cells, doxazosin was less cytotoxic and increased p-EGFRTyr1048, p-AktSer473 and p-GSK-3ßSer9 levels. Moreover, the drug was able to protect hippocampal slices from amyloid-ß toxicity through prevention of GSK-3ß activation and of Tau hyperphosphorylation. Therefore, our results show that doxazosin has antitumor activity against undifferentiated NB and is neuroprotective on an in vitro model of Alzheimer's disease.


Assuntos
Doença de Alzheimer/metabolismo , Antineoplásicos/farmacologia , Doxazossina/farmacologia , Neuroblastoma/metabolismo , Fármacos Neuroprotetores/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 1/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Doxazossina/uso terapêutico , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Masculino , Neuroblastoma/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Técnicas de Cultura de Órgãos , Ratos , Ratos Wistar
16.
Front Immunol ; 9: 2500, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30420858

RESUMO

Since 2006, meningococcal serogroup C (MenC) conjugate (MCC) vaccines have been supplied by the Brazilian government for HIV-infected children under 13 years old. For measuring protection against MenC, the serum bactericidal antibody (SBA) assay is the method of choice. The characterization of T follicular helper cells (TFH) cells has been an area of intensive study because of their significance in multiple human diseases and in vaccinology. The objective of this study was to characterize the phenotype of peripheral TFH cells and B cells and how they associated with each other and with SBA levels induced by vaccination as well as with serum cytokine levels of HIV-infected and non-infected children and adolescents. We found that CD27-IgD-CD21-CD38+ (exhausted B cells) as well as short-lived plasmablasts (CD27+IgD-CD21-CD38+) are increased in cART treated HIV patients and negatively associated with MCC vaccine induced SBA levels. Baseline frequency of activated peripheral TFH cells was a negative correlate for SBA response to MCC vaccine but positively correlated with circulating plasmablast frequency. Baseline IL4-levels positively associated with SBA response but showed a negative correlation with activated peripheral TFH cells frequency. The increased frequency of activated peripheral TFH cells found in non-responders to the vaccine implies that higher activation/differentiation of CD4 T cells within the lymph node is not necessarily associated with induction of vaccine responses.


Assuntos
Linfócitos B/imunologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Meningites Bacterianas/imunologia , Vacinas Meningocócicas/imunologia , Neisseria meningitidis Sorogrupo C/fisiologia , Linfócitos T Auxiliares-Indutores/imunologia , Adolescente , Anticorpos Antibacterianos/sangue , Circulação Sanguínea , Criança , Pré-Escolar , Estudos de Coortes , Resistência à Doença , Feminino , Centro Germinativo/imunologia , Humanos , Interleucina-4/sangue , Ativação Linfocitária , Masculino , Estudos Prospectivos , Vacinação
17.
Endocr Connect ; 7(8): 907-913, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29973373

RESUMO

BACKGROUND: Computerized image analysis seems to represent a promising diagnostic possibility for thyroid tumors. Our aim was to evaluate the discriminatory diagnostic efficiency of computerized image analysis of cell nuclei from histological materials of follicular tumors. METHODS: We studied paraffin-embedded materials from 42 follicular adenomas (FA), 47 follicular variants of papillary carcinomas (FVPC) and 20 follicular carcinomas (FC) by the software ImageJ. Based on the nuclear morphometry and chromatin texture, the samples were classified as FA, FC or FVPC using the Classification and Regression Trees method. RESULTS: We observed high diagnostic sensitivity and specificity rates (FVPC: 89.4% and 100%; FC: 95.0% and 92.1%; FA: 90.5 and 95.5%, respectively). When the tumors were compared by pairs (FC vs FA, FVPC vs FA), 100% of the cases were classified correctly. CONCLUSION: The computerized image analysis of nuclear features showed to be a useful diagnostic support tool for the histological differentiation between follicular adenomas, follicular variants of papillary carcinomas and follicular carcinomas.

18.
Acta cir. bras ; 32(12): 1026-1035, Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886192

RESUMO

Abstract Purpose: To investigate the efficacy of allogeneic mesenchymal stem-cells and autologous mononuclear cells to promote sensorimotor recovery and tissue rescue. Methods: Female rabbits were submitted to the epidural balloon inflation method and the intravenous cells administrations were made after 8 hours or seven days after injury induction. Sensorimotor evaluation of the hindlimbs was performed, and the euthanasia was made thirty days after the treatment. Spinal cords were stained with hematoxylin and eosin. Results: Both therapies given 8 hours after the injury promoted the sensorimotor recovery after a week. Only the group treated after a week with mononuclear cells showed no significant recovery at post-injury day 14. In the days 21 and 28, all treatments promoted significant recovery. Histopathological analysis showed no difference among the experimental groups. Our results showed that both bone marrow-derived cell types promoted significant sensorimotor recovery after injury, and the treatment made at least a week after injury is efficient. Conclusion: The possibilities of therapy with bone marrow-derived cells are large, increasing the therapeutic arsenal for the treatment of spinal cord injury.


Assuntos
Animais , Feminino , Ratos , Traumatismos da Medula Espinal/cirurgia , Leucócitos Mononucleares/transplante , Transplante de Medula Óssea/métodos , Recuperação de Função Fisiológica , Transplante de Células-Tronco Mesenquimais/métodos , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/patologia , Fatores de Tempo , Transplante Autólogo , Transplante Homólogo , Tomografia Computadorizada por Raios X , Modelos Animais de Doenças , Vias Neurais
19.
Zoolog Sci ; 34(4): 300-311, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28770679

RESUMO

Chemical coding of stomatogastric nervous system (STNS) and enteric nervous system (ENS) of midgut and hindgut in the snail Megalobulimus abbreviatus was investigated using histochemistry, histofluorescence, and immunohistochemistry. The gastrointestinal plexuses, constituted by intrinsic neurons and fibers originating from the subesophageal ganglia and/or STNS, showed intense acetylcholinesterase (AChE) and nicotinamide adenine dinucleotide diaphorase (NADPHd) activity. The enteric neurons and fibers with AChE activity are scattered in the submucosa and between both muscular layers of gastrointestinal tract, whereas NADPHd neurons and fibers are more abundant between muscular layers than in the submucosa. Catecholaminergic nerve fibers and varicosities are found mainly within the submucosa across the mid- and hindgut. Serotoninand FMRFamide-immunoreactive neurons and fibers originating from the STNS are distributed in the submucosa of the intestine and rectum. FMRFamide-immunoreactive neurons and fibers are present in the mucosa, submucosa, and muscular layers of mid- and hindgut. The neuron-like intraepithelial cells exhibited AChE activity, a few NADPHd activity, and immunoreactivity for serotonin and FMRFamide. Intense glial fibrillary acidic protein (GFAP) immunoreaction is found throughout the intestine plexuses and in the STNS ganglia. The GFAP immunoreaction in intramural plexuses suggests the presence of glial cells as an important component of ENS in this pulmonate snail.


Assuntos
Caramujos/fisiologia , Animais , Trato Gastrointestinal/inervação , Trato Gastrointestinal/fisiologia , Imuno-Histoquímica , Fenômenos Fisiológicos do Sistema Nervoso , Neurônios/fisiologia
20.
Mol Neurobiol ; 54(8): 6261-6272, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-27714633

RESUMO

Glioblastoma (GBM) is the most common and aggressive primary malignant brain tumor in adults. Hypoxia is a distinct feature in GBM and plays a significant role in tumor progression, resistance to treatment, and poor outcome. However, there is lack of studies relating type of cell death, status of Akt phosphorylation on Ser473, mitochondrial membrane potential, and morphological changes of tumor cells after hypoxia and reoxygenation. The rat glioma C6 cell line was exposed to oxygen deprivation (OD) in 5 % fetal bovine serum (FBS) or serum-free media followed by reoxygenation (RO). OD induced apoptosis on both 5 % FBS and serum-free groups. Overall, cells on serum-free media showed more profound morphological changes than cells on 5 % FBS. Moreover, our results suggest that OD combined with absence of serum provided a favorable environment for glioblastoma dedifferentiation to cancer stem cells, since nestin, and CD133 levels increased. Reoxygenation is present in hypoxic tumors through microvessel formation and cell migration to oxygenated areas. However, few studies approach these phenomena when analyzing hypoxia. We show that RO caused morphological alterations characteristic of cells undergoing a differentiation process due to increased GFAP. In the present study, we characterized an in vitro hypoxic microenvironment associated with GBM tumors, therefore contributing with new insights for the development of therapeutics for resistant glioblastoma.


Assuntos
Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Hipóxia/patologia , Células-Tronco Neoplásicas/patologia , Neurônios/patologia , Microambiente Tumoral , Animais , Apoptose/fisiologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Glioblastoma/metabolismo , Hipóxia/metabolismo , Potencial da Membrana Mitocondrial/fisiologia , Células-Tronco Neoplásicas/metabolismo , Neurônios/metabolismo , Oxigênio/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos
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