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1.
Int J Mol Sci ; 24(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37511139

RESUMO

The global rise of single-use throw-away plastic products has elicited a massive increase in the nano/microplastics (N/MPLs) exposure burden in humans. Recently, it has been demonstrated that disposable period products may release N/MPLs with usage, which represents a potential threat to women's health which has not been scientifically addressed yet. By using polyethyl ene (PE) particles (200 nm to 9 µm), we showed that acute exposure to a high concentration of N/MPLs induced cell toxicity in vaginal keratinocytes after effective cellular uptake, as viability and apoptosis data suggest, along with transmission electron microscopy (TEM) observations. The internalised N/MPLs altered the expression of junctional and adherence proteins and the organisation of the actin cortex, influencing the level of genes involved in oxidative stress signalling pathways and that of miRNAs related to epithelial barrier function. When the exposure to PE N/MPLs was discontinued or became chronic, cells were able to recover from the negative effects on viability and differentiation/proliferation gene expression in a few days. However, in all cases, PE N/MPL exposure prompted a sustained alteration of DNA methyltransferase and DNA demethylase expression, which might impact epigenetic regulation processes, leading to accelerated cell ageing and inflammation, or the occurrence of malignant transformation.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Feminino , Microplásticos/toxicidade , Plásticos , Polietileno , Epigênese Genética , Queratinócitos/química , Poluentes Químicos da Água/toxicidade
2.
Int J Mol Sci ; 24(8)2023 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-37108134

RESUMO

Nanomaterials are gaining increasing attention as innovative materials in medicine. Among nanomaterials, zinc oxide (ZnO) nanostructures are particularly appealing because of their opto-electrical, antimicrobial, and photochemical properties. Although ZnO is recognized as a safe material and the Zn ion (Zn2+) concentration is strictly regulated at a cellular and systemic level, different studies have demonstrated cellular toxicity of ZnO nanoparticles (ZnO-NPs) and ZnO nanorods (ZnO-NRs). Recently, ZnO-NP toxicity has been shown to depend on the intracellular accumulation of ROS, activation of autophagy and mitophagy, as well as stabilization and accumulation of hypoxia-inducible factor-1α (HIF-1α) protein. However, if the same pathway is also activated by ZnO-NRs and how non-cancer cells respond to ZnO-NR treatment, are still unknown. To answer to these questions, we treated epithelial HaCaT and breast cancer MCF-7 cells with different ZnO-NR concentrations. Our results showed that ZnO-NR treatments increased cell death through ROS accumulation, HIF-1α and endothelial PAS domain protein 1 (EPAS1) activation, and induction of autophagy and mitophagy in both cell lines. These results, while on one side, confirmed that ZnO-NRs can be used to reduce cancer growth, on the other side, raised some concerns on the activation of a hypoxic response in normal cells that, in the long run, could induce cellular transformation.


Assuntos
Neoplasias , Óxido de Zinco , Humanos , Mitofagia , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Espécies Reativas de Oxigênio/metabolismo , Autofagia , Células MCF-7 , Hipóxia , Fator 1 Induzível por Hipóxia
3.
Cells ; 12(5)2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36899828

RESUMO

Life on Earth has evolved in the presence of a gravity constraint. Any change in the value of such a constraint has important physiological effects. Gravity reduction (microgravity) alters the performance of muscle, bone and, immune systems among others. Therefore, countermeasures to limit such deleterious effects of microgravity are needed considering future Lunar and Martian missions. Our study aims to demonstrate that the activation of mitochondrial Sirtuin 3 (SIRT3) can be exploited to reduce muscle damage and to maintain muscle differentiation following microgravity exposure. To this effect, we used a RCCS machine to simulate microgravity on ground on a muscle and cardiac cell line. During microgravity, cells were treated with a newly synthesized SIRT3 activator, called MC2791 and vitality, differentiation, ROS and, autophagy/mitophagy were measured. Our results indicate that SIRT3 activation reduces microgravity-induced cell death while maintaining the expression of muscle cell differentiation markers. In conclusion, our study demonstrates that SIRT3 activation could represent a targeted molecular strategy to reduce muscle tissue damage caused by microgravity.


Assuntos
Marte , Sirtuína 3 , Ausência de Peso , Meio Ambiente Extraterreno , Músculos/metabolismo , Sirtuína 3/metabolismo , Humanos
4.
J Hematol Oncol ; 15(1): 145, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36224639

RESUMO

BACKGROUND: Metastatic prostate cancer (PC) is a leading cause of cancer death in men worldwide. Targeting of the culprits of disease progression is an unmet need. Interleukin (IL)-30 promotes PC onset and development, but whether it can be a suitable therapeutic target remains to be investigated. Here, we shed light on the relationship between IL30 and canonical PC driver genes and explored the anti-tumor potential of CRISPR/Cas9-mediated deletion of IL30. METHODS: PC cell production of, and response to, IL30 was tested by flow cytometry, immunoelectron microscopy, invasion and migration assays and PCR arrays. Syngeneic and xenograft models were used to investigate the effects of IL30, and its deletion by CRISPR/Cas9 genome editing, on tumor growth. Bioinformatics of transcriptional data and immunopathology of PC samples were used to assess the translational value of the experimental findings. RESULTS: Human membrane-bound IL30 promoted PC cell proliferation, invasion and migration in association with STAT1/STAT3 phosphorylation, similarly to its murine, but secreted, counterpart. Both human and murine IL30 regulated PC driver and immunity genes and shared the upregulation of oncogenes, BCL2 and NFKB1, immunoregulatory mediators, IL1A, TNF, TLR4, PTGS2, PD-L1, STAT3, and chemokine receptors, CCR2, CCR4, CXCR5. In human PC cells, IL30 improved the release of IGF1 and CXCL5, which mediated, via autocrine loops, its potent proliferative effect. Deletion of IL30 dramatically downregulated BCL2, NFKB1, STAT3, IGF1 and CXCL5, whereas tumor suppressors, primarily SOCS3, were upregulated. Syngeneic and xenograft PC models demonstrated IL30's ability to boost cancer proliferation, vascularization and myeloid-derived cell infiltration, which were hindered, along with tumor growth and metastasis, by IL30 deletion, with improved host survival. RNA-Seq data from the PanCancer collection and immunohistochemistry of high-grade locally advanced PCs demonstrated an inverse association (chi-squared test, p = 0.0242) between IL30 and SOCS3 expression and a longer progression-free survival of patients with IL30NegSOCS3PosPC, when compared to patients with IL30PosSOCS3NegPC. CONCLUSIONS: Membrane-anchored IL30 expressed by human PC cells shares a tumor progression programs with its murine homolog and, via juxtacrine signals, steers a complex network of PC driver and immunity genes promoting prostate oncogenesis. The efficacy of CRISPR/Cas9-mediated targeting of IL30 in curbing PC progression paves the way for its clinical use.


Assuntos
Antígeno B7-H1 , Neoplasias da Próstata , Animais , Antígeno B7-H1/genética , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Proliferação de Células , Quimiocina CXCL5/genética , Quimiocina CXCL5/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Humanos , Fator de Crescimento Insulin-Like I , Interleucinas/metabolismo , Masculino , Camundongos , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Receptores de Quimiocinas , Proteína 3 Supressora da Sinalização de Citocinas/genética , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
5.
Int J Mol Sci ; 21(21)2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33114229

RESUMO

Extracellular vesicles (EVs) play a crucial role in the intercellular crosstalk. Mesenchymal stem cell-derived EVs (MSC-EVs), displaying promising therapeutic roles, contribute to the strong rationale for developing EVs as an alternative therapeutic option. EV analysis still represents one of the major issues to be solved in order to translate the use of MSC-EV detection in clinical settings. Even if flow cytometry (FC) has been largely applied for EV studies, the lack of consensus on protocols for FC detection of EVs generated controversy. Standard FC procedures, based on scatter measurements, only allows the detection of the "tip of the iceberg" of all EVs. We applied an alternative FC approach based on the use of a trigger threshold on a fluorescence channel. The EV numbers obtained by the application of the fluorescence triggering resulted significantly higher in respect to them obtained from the same samples acquired by placing the threshold on the side scatter (SSC) channel. The analysis of EV concentrations carried out by three different standardized flow cytometers allowed us to achieve a high level of reproducibility (CV < 20%). By applying the here-reported method highly reproducible results in terms of EV analysis and concentration measurements were obtained.


Assuntos
Vesículas Extracelulares/metabolismo , Citometria de Fluxo/métodos , Células-Tronco Mesenquimais/citologia , Animais , Células Cultivadas , Difusão Dinâmica da Luz , Separação Imunomagnética , Células-Tronco Mesenquimais/metabolismo
6.
PLoS Pathog ; 16(9): e1008855, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32986788

RESUMO

SAMHD1 is a host restriction factor that functions to restrict both retroviruses and DNA viruses, based on its nuclear deoxynucleotide triphosphate (dNTP) hydrolase activity that limits availability of intracellular dNTP pools. In the present study, we demonstrate that SAMHD1 expression was increased following human cytomegalovirus (HCMV) infection, with only a modest effect on infectious virus production. SAMHD1 was rapidly phosphorylated at residue T592 after infection by cellular cyclin-dependent kinases, especially Cdk2, and by the viral kinase pUL97, resulting in a significant fraction of phosho-SAMHD1 being relocalized to the cytoplasm of infected fibroblasts, in association with viral particles and dense bodies. Thus, our findings indicate that HCMV-dependent SAMHD1 cytoplasmic delocalization and inactivation may represent a potential novel mechanism of HCMV evasion from host antiviral restriction activities.


Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/patogenicidade , Infecções por Herpesviridae/metabolismo , Proteína 1 com Domínio SAM e Domínio HD/genética , Antivirais/farmacologia , Quinases Ciclina-Dependentes/metabolismo , Citomegalovirus/genética , Citoplasma/metabolismo , Citoplasma/virologia , Humanos , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Fosforilação , Replicação Viral/efeitos dos fármacos
7.
Virulence ; 10(1): 1013-1025, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31771413

RESUMO

Calcium signaling can elicit different pathways involved in an extreme variety of biological processes. Calcium levels must be tightly regulated in a spatial and temporal manner in order to be efficiently and properly utilized in the host physiology. The Ca2+-ATPase, encoded by pmr-1 gene, was first identified in yeast and localized to the Golgi and it appears to be involved in calcium homeostasis. PMR-1 function is evolutionary conserved from yeast to human, where mutations in the orthologous gene ATP2C1 cause Hailey-Hailey disease. In this work, we used the Caenorhabditis elegans model system to gain insight into the downstream response elicited by the loss of pmr-1 gene. We found that pmr-1 knocked down animals not only showed defects in the oligosaccharide structure of glycoproteins at the cell surface but also were characterized by reduced susceptibility to bacterial infection. Although increased resistance to the infection might be related to lack of regular recognition of C. elegans surface glycoproteins by microbial agents, we provide genetic evidence that pmr-1 interfered nematodes mounted a stronger innate immune response to Gram-positive bacterial infection. Thus, our observations indicate pmr-1 as a candidate gene implicated in mediating the worm's innate immune response.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Caenorhabditis elegans/microbiologia , ATPases Transportadoras de Cálcio/genética , Imunidade Inata , Infecções Estafilocócicas/microbiologia , Animais , Caenorhabditis elegans/imunologia , Técnicas de Silenciamento de Genes , Glicosilação , Mutação , Oligossacarídeos/química , Staphylococcus aureus/patogenicidade , Estresse Fisiológico
8.
Br J Cancer ; 121(9): 768-775, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31558803

RESUMO

BACKGROUND: Current approaches aimed at inducing immunogenic cell death (ICD) to incite an immune response against cancer neoantigens are based on the use of chemotherapeutics and other agents. Results are hampered by issues of efficacy, combinatorial approaches, dosing and toxicity. Here, we adopted a strategy based on the use of an immunomolecule that overcomes pharmachemical limitations. METHODS: Cytofluorometry, electron microscopy, RT-PCR, western blotting, apotome immunofluorescence, MLR and xenografts. RESULTS: We report that an ICD process can be activated without the use of pharmacological compounds. We show that in Kras-mut/TP53-mut colorectal cancer cells the 15 kDa ßGBP cytokine, a T cell effector with onco-suppressor properties and a potential role in cancer immunosurveillance, induces key canonical events required for ICD induction. We document ER stress, autophagy that extends from cancer cells to the corresponding xenograft tumours, CRT cell surface shifting, ATP release and evidence of dendritic cell activation, a process required for priming cytotoxic T cells into a specific anticancer immunogenic response. CONCLUSIONS: Our findings provide experimental evidence for a rationale to explore a strategy based on the use of an immunomolecule that as a single agent couples oncosuppression with the activation of procedures necessary for the induction of long term response to cancer.


Assuntos
Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Proteínas Proto-Oncogênicas p21(ras)/imunologia , Trifosfato de Adenosina/imunologia , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Morte Celular Autofágica/efeitos dos fármacos , Morte Celular Autofágica/imunologia , Calreticulina/imunologia , Calreticulina/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Morte Celular/imunologia , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/imunologia , Feminino , Galectinas/farmacologia , Xenoenxertos , Humanos , Vigilância Imunológica , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos
9.
Cancers (Basel) ; 11(3)2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30813557

RESUMO

In this review, we propose that paraganglioma is a fundamentally organized, albeit aberrant, tissue composed of neoplastic vascular and neural cell types that share a common origin from a multipotent mesenchymal-like stem/progenitor cell. This view is consistent with the pseudohypoxic footprint implicated in the molecular pathogenesis of the disease, is in harmony with the neural crest origin of the paraganglia, and is strongly supported by the physiological model of carotid body hyperplasia. Our immunomorphological and molecular studies of head and neck paragangliomas demonstrate in all cases relationships between the vascular and the neural tumor compartments, that share mesenchymal and immature vasculo-neural markers, conserved in derived cell cultures. This immature, multipotent phenotype is supported by constitutive amplification of NOTCH signaling genes and by loss of the microRNA-200s and -34s, which control NOTCH1, ZEB1, and PDGFRA in head and neck paraganglioma cells. Importantly, the neuroepithelial component is distinguished by extreme mitochondrial alterations, associated with collapse of the ΔΨm. Finally, our xenograft models of head and neck paraganglioma demonstrate that mesenchymal-like cells first give rise to a vasculo-angiogenic network, and then self-organize into neuroepithelial-like clusters, a process inhibited by treatment with imatinib.

11.
Acta Neuropathol ; 135(5): 779-798, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29305721

RESUMO

Tumours can be viewed as aberrant tissues or organs sustained by tumorigenic stem-like cells that engage into dysregulated histo/organogenetic processes. Paragangliomas, prototypical organoid tumours constituted by dysmorphic variants of the vascular and neural tissues found in normal paraganglia, provide a model to test this hypothesis. To understand the origin of paragangliomas, we built a biobank comprising 77 cases, 18 primary cultures, 4 derived cell lines, 80 patient-derived xenografts and 11 cell-derived xenografts. We comparatively investigated these unique complementary materials using morphofunctional, ultrastructural and flow cytometric assays accompanied by microRNA studies. We found that paragangliomas contain stem-like cells with hybrid mesenchymal/vasculoneural phenotype, stabilized and expanded in the derived cultures. The viability and growth of such cultures depended on the downregulation of the miR-200 and miR-34 families, which allowed high PDGFRA and ZEB1 protein expression levels. Both tumour tissue- and cell culture-derived xenografts recapitulated the vasculoneural paraganglioma structure and arose from mesenchymal-like cells through a fixed developmental sequence. First, vasculoangiogenesis organized the microenvironment, building a perivascular niche which in turn supported neurogenesis. Neuroepithelial differentiation was associated with severe mitochondrial dysfunction, not present in cultured paraganglioma cells, but acquired in vivo during xenograft formation. Vasculogenesis was the Achilles' heel of xenograft development. In fact, imatinib, that targets endothelial-mural signalling, blocked paraganglioma xenograft formation (11 xenografts from 12 cell transplants in the control group versus 2 out of 10 in the treated group, P = 0.0015). Overall our key results were unaffected by the SDHx gene carrier status of the patient, characterized for 70 out of 77 cases. In conclusion, we explain the biphasic vasculoneural structure of paragangliomas and identify an early and pharmacologically actionable phase of paraganglioma organization.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/fisiopatologia , Mesilato de Imatinib/uso terapêutico , Paraganglioma/tratamento farmacológico , Paraganglioma/fisiopatologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Mesilato de Imatinib/farmacologia , Camundongos Endogâmicos NOD , Camundongos SCID , MicroRNAs/metabolismo , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Organogênese/efeitos dos fármacos , Organogênese/fisiologia , Paraganglioma/genética , Paraganglioma/patologia , Cultura Primária de Células , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/fisiologia , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Thromb Haemost ; 116(6): 1100-1110, 2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-27683757

RESUMO

Platelet multidrug resistance protein4 (MRP4)-overexpression has a role in reducing aspirin action. Aspirin in vivo treatment enhances platelet MRP4 expression and MRP4 mediated transport inhibition reduces platelet function and delays thrombus formation. The aim of our work was to verify whether MRP4 expression is enhanced in platelets obtained from patients under chronic aspirin treatment and whether it correlates with residual platelet reactivity. We evaluated changes on mRNA and protein-MRP4 expression and platelet aggregation in four populations: healthy volunteers (HV), aspirin-free control population (CTR), patients who started the treatment less than one month ago (ASA<1 month patients) and aspirinated patients who started the treatment more than two months ago (ASA>2 months patients). In platelets obtained from ASA>2 months patients, it was found a statistically significant MRP4 enhancement of both mRNA and protein expression compared to HV, CTR and ASA<1 month patients. Platelets obtained from ASA>2 months patients that present high levels of platelet MRP4, have higher serum TxB2 levels and collagen-induced platelet aggregation compared to patient with low levels of MRP4 in platelets. In addition collagen induced platelet aggregation is higher in in vitro aspirinated platelets obtained from patients with high levels of MRP4 patients compared to those obtained from patients with low MRP4 levels. We can assert that, in patients under chronic aspirin treatment, platelets that present high MRP4 levels have an increase of residual platelet reactivity, which is due in part to incomplete COX-1 inhibition, and in part to COX-1-independent mechanism.


Assuntos
Aspirina/farmacologia , Plaquetas/efeitos dos fármacos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Idoso , Idoso de 80 Anos ou mais , Plaquetas/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária , Inibidores da Agregação Plaquetária , Testes de Função Plaquetária
13.
Cancer Lett ; 366(2): 191-7, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26184999

RESUMO

PEL cells relay on the constitutive activation of STAT3 for their survival, thus its inhibition by AG490 leads to apoptotic cell death. In this study, we found that the cytotoxic activity of AG490 correlated with the reduction of HSP70 and its master regulator HSF1 that, based on knocking-down experiments, was found to play a pro-survival role in PEL cells. To counteract the pro-death effect mediated by HSF1/HSP70 down-regulation, AG490 induced a complete autophagy, whose inhibition potentiated its cytotoxic effect against PEL cells. AG490 as well as HSF1 siRNA reduced the expression of Mcl-1, a Bcl-2 family member that negatively regulates apoptosis and autophagy. These results suggest that STAT3 inhibition, by down-regulating the expression of HSF1/HSP70, reduces Mcl-1 and leads to both apoptosis and autophagy induction in PEL cells.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ligação a DNA/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Linfoma de Células B/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/efeitos dos fármacos , Proteínas Tirosina Quinases/antagonistas & inibidores , Fatores de Transcrição/efeitos dos fármacos , Tirfostinas/farmacologia , Apoptose/efeitos dos fármacos , Autofagia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Regulação para Baixo , Fatores de Transcrição de Choque Térmico , Humanos , Linfoma de Células B/imunologia , Linfoma de Células B/metabolismo , Linfoma de Células B/patologia , Fosforilação , Fator de Transcrição STAT3/efeitos dos fármacos , Células Tumorais Cultivadas
14.
J Virol ; 88(21): 12715-26, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25142602

RESUMO

UNLABELLED: Autophagy is a catabolic pathway that helps cells to survive under stressful conditions. Cells also use autophagy to clear microbiological infections, but microbes have learned how to manipulate the autophagic pathway for their own benefit. The experimental evidence obtained in this study suggests that the autophagic flux is blocked at the final steps during the reactivation of Epstein-Barr virus (EBV) from latency. This is indicated by the level of the lipidated form of LC3 that does not increase in the presence of bafilomycin and by the lack of colocalization of autophagosomes with lysosomes, which correlates with reduced Rab7 expression. Since the inhibition of the early phases of autophagy impaired EBV replication and viral particles were observed in autophagic vesicles in the cytoplasm of producing cells, we suggest that EBV exploits the autophagic machinery for its transportation in order to enhance viral production. The autophagic block was not mediated by ZEBRA, an immediate-early EBV lytic gene, whose transfection in Ramos, Akata, and 293 cells promoted a complete autophagic flux. The block occurred only when the complete set of EBV lytic genes was expressed. We suggest that the inhibition of the early autophagic steps or finding strategies to overcome the autophagic block, allowing viral degradation into the lysosomes, can be exploited to manipulate EBV replication. IMPORTANCE: This study shows, for the first time, that autophagy is blocked at the final degradative steps during EBV replication in several cell types. Through this block, EBV hijacks the autophagic vesicles for its intracellular transportation and enhances viral production. A better understanding of virus-host interactions could help in the design of new therapeutic approaches against EBV-associated malignancies.


Assuntos
Autofagia , Herpesvirus Humano 4/fisiologia , Interações Hospedeiro-Patógeno , Evasão da Resposta Imune , Ativação Viral , Replicação Viral , Animais , Linhagem Celular , Humanos
15.
Br J Clin Pharmacol ; 78(6): 1343-53, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24902864

RESUMO

AIM: The aim of the study was to investigate whether human megakaryocytic cells have an adaptive response to aspirin treatment, leading to an enhancement of multidrug resistance protein-4 (MRP4) expression in circulating platelets responsible for a reduced aspirin action. We recently found that platelet MRP4 overexpression has a role in reducing aspirin action in patients after by-pass surgery. Aspirin enhances MRP4-mRNA levels in rat liver and drug administration transcriptionally regulates MRP4 gene expression through peroxisome proliferator-activated receptor-α (PPARα). METHODS: The effects induced by aspirin or PPARα agonist (WY14643) on MRP4 modulation were evaluated in vitro in a human megakaryoblastic DAMI cell line, in megakaryocytes (MKs) and in platelets obtained from human haematopoietic progenitor cell (HPC) cultures, and in vivo platelets obtained from aspirin treated healthy volunteers (HV). RESULTS: In DAMI cells, aspirin and WY14643 treatment induced a significant increase in MRP4 and PPARα expression. In human MKs grown in the presence of either aspirin or WY14643, MRP4 and PPARα-mRNA were higher than in control cultures and derived platelets showed an enhancement in MRP4 protein expression. The ability of aspirin to modulate MRP4 expression in MKs and to transfer it to platelets was also confirmed in vivo. In fact, we found the highest MRP4 mRNA and protein expression in platelets obtained from HV after 15 days' aspirin treatment. CONCLUSIONS: The present study provides evidence, for the first time, that aspirin treatment affects the platelet protein pattern through MK genomic modulation. This work represents an innovative and attractive approach, useful both to identify patients less sensitive to aspirin and to improve pharmacological treatment in cardiovascular high-risk patients.


Assuntos
Aspirina/farmacologia , Megacariócitos/efeitos dos fármacos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Adulto , Células Cultivadas , Feminino , Humanos , Masculino , Megacariócitos/metabolismo , Pessoa de Meia-Idade , PPAR alfa/genética , RNA Mensageiro/análise , Regulação para Cima
16.
Acta Neuropathol ; 126(4): 575-94, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23955600

RESUMO

Head and neck paragangliomas, rare neoplasms of the paraganglia composed of nests of neurosecretory and glial cells embedded in vascular stroma, provide a remarkable example of organoid tumor architecture. To identify genes and pathways commonly deregulated in head and neck paraganglioma, we integrated high-density genome-wide copy number variation (CNV) analysis with microRNA and immunomorphological studies. Gene-centric CNV analysis of 24 cases identified a list of 104 genes most significantly targeted by tumor-associated alterations. The "NOTCH signaling pathway" was the most significantly enriched term in the list (P = 0.002 after Bonferroni or Benjamini correction). Expression of the relevant NOTCH pathway proteins in sustentacular (glial), chief (neuroendocrine) and endothelial cells was confirmed by immunohistochemistry in 47 head and neck paraganglioma cases. There were no relationships between level and pattern of NOTCH1/JAG2 protein expression and germline mutation status in the SDH genes, implicated in paraganglioma predisposition, or the presence/absence of immunostaining for SDHB, a surrogate marker of SDH mutations. Interestingly, NOTCH upregulation was observed also in cases with no evidence of CNVs at NOTCH signaling genes, suggesting altered epigenetic modulation of this pathway. To address this issue we performed microarray-based microRNA expression analyses. Notably 5 microRNAs (miR-200a,b,c and miR-34b,c), including those most downregulated in the tumors, correlated to NOTCH signaling and directly targeted NOTCH1 in in vitro experiments using SH-SY5Y neuroblastoma cells. Furthermore, lentiviral transduction of miR-200s and miR-34s in patient-derived primary tympano-jugular paraganglioma cell cultures was associated with NOTCH1 downregulation and increased levels of markers of cell toxicity and cell death. Taken together, our results provide an integrated view of common molecular alterations associated with head and neck paraganglioma and reveal an essential role of NOTCH pathway deregulation in this tumor type.


Assuntos
Epigênese Genética/fisiologia , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Paraganglioma/genética , Paraganglioma/patologia , Receptores Notch/genética , Receptores Notch/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Western Blotting , Caspases/metabolismo , Morte Celular/genética , Linhagem Celular Tumoral , Análise Mutacional de DNA , Imunofluorescência , Humanos , Imuno-Histoquímica , Lentivirus/genética , Análise em Microsséries , Microscopia Imunoeletrônica , Nervos Periféricos/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Succinato Desidrogenase/genética , Transfecção
17.
Eur J Med Chem ; 65: 102-11, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23702472

RESUMO

Thirty-eight new (4-(4-substituted-phenyl/2,4-disubstituted-phenyl)-thiazol-2-yl)hydrazine derivatives were synthesized in good yield and assayed for their in vitro anti-Candida activity, compared to topical and systemic antifungal drugs, against twenty-two clinical isolates of Candida spp. The concurrent presence of aliphatic chains or cycloaliphatic rings at N1-hydrazine and a 4-methyl/4-methoxyphenyl at C4 position of the thiazole nucleus exhibited an interesting anti-Candida inhibitory activity. Moreover, some of the most active compounds showed synergistic antifungal effects and lower cell toxicity when combined with clotrimazole.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Hidrazinas/farmacologia , Tiazóis/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Hidrazinas/síntese química , Hidrazinas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química
18.
PLoS One ; 7(4): e36190, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22558377

RESUMO

Colorectal cancer (CRC) is associated with lifestyle factors that affect insulin/IGF signaling, of which the insulin receptor substrate 1 (IRS1) is a key transducer. We investigated expression, localization and pathologic correlations of IRS1 in cancer-uninvolved colonic epithelium, primary CRCs with paired liver metastases and in vitro polarizing Caco2 and HT29 cells. IRS1 mRNA and protein resulted higher, relative to paired mucosa, in adenomas of familial adenomatous polyposis patients and in CRCs that overexpressed c-MYC, ß-catenin, InsRß, and IGF1R. Analysis of IRS1 immunostaining in 24 cases of primary CRC with paired colonic epithelium and hepatic metastasis showed that staining intensity was significantly higher in metastases relative to both primary CRC (P<0.01) and colonic epithelium (P<0.01). Primary and metastatic CRCs, compared to colonic epithelium, contained significantly higher numbers of IRS1-positive cells (P = 0.013 and P = 0.014, respectively). Pathologic correlations in 163 primary CRCs revealed that diffuse IRS1 staining was associated with tumors combining differentiated phenotype and aggressive markers (high Ki67, p53, and ß-catenin). In Caco 2 IRS1 and InsR were maximally expressed after polarization, while IGF1R was highest in pre-polarized cells. No nuclear IRS1 was detected, while, with polarization, phosphorylated IRS1 (pIRS1) shifted from the lateral to the apical plasma membrane and was expressed in surface cells only. In HT29, that carry mutations constitutively activating survival signaling, IRS1 and IGF1R decreased with polarization, while pIRS1 localized in nuclear spots throughout the course. Overall, these data provide evidence that IRS1 is modulated according to CRC differentiation, and support a role of IRS1 in CRC progression and liver metastatization.


Assuntos
Diferenciação Celular , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Adulto , Idoso , Células CACO-2 , Polaridade Celular , Colo/citologia , Colo/metabolismo , Colo/patologia , Neoplasias Colorretais/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Células HT29 , Humanos , Mucosa Intestinal/citologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Masculino , Transporte Proteico
19.
PLoS One ; 7(3): e31732, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22412839

RESUMO

To understand how cytotoxic agent-induced cancer cell death affects the immune system is of fundamental importance to stimulate immune response to counteract the high mortality due to cancer. Here we compared the immunogenicity of Primary Effusion Lymphoma (PEL) cell death induced by anticancer drug Bortezomib (Velcade) and Tyrphostin AG 490, a Janus Activated Kinase 2/signal trasducer and activator of transcription-3 (JAK2/STAT3) inhibitor. We show that both treatments were able to induce PEL apoptosis with similar kinetics and promote dendritic cells (DC) maturation. The surface expression of molecules involved in immune activation, namely calreticulin (CRT), heat shock proteins (HSP) 90 and 70 increased in dying cells. This was correlated with DC activation. We found that PEL cell death induced by Bortezomib was more effective in inducing uptake by DC compared to AG 490 or combination of both drugs. However the DC activation induced by all treatments was completely inhibited when these cells were pretreated with a neutralizing antiboby directed against the HSP90/70 and CRT common receptor, CD91. The activation of DC by Bortezomib and AG 490 treated PEL cells, as seen in the present study, might have important implications for a combined chemo and immunotherapy in such patients.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Células Dendríticas/imunologia , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Linfoma de Efusão Primária/imunologia , Ácidos Borônicos/farmacologia , Bortezomib , Calreticulina/metabolismo , Linhagem Celular , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Cinética , Fagocitose/imunologia , Transporte Proteico/efeitos dos fármacos , Pirazinas/farmacologia , Tirfostinas/farmacologia
20.
J Occup Environ Med ; 53(9): 1054-60, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21866053

RESUMO

OBJECTIVE: To investigate the effects of palladium (Pd) nanoparticles on cytokine release from peripheral blood mononuclear cells (PBMCs) of control or Pd-sensitized nonatopic women. METHODS: TNF-α, IL-5, IL-10 and IFN-γ release and/or expression from PBMCs incubated in presence of 5 to 10 nm Pd nanoparticles or Pd salt (potassium hexachloropalladate) were determined by enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction analysis. Transmission electronmicroscopy was performed. RESULTS: In lipopolysaccharide-stimulated PBMCs from controls, Pd salt inhibited IFN-γ and IL-10 release, whereas Pd nanoparticles enhanced IFN-γ release and inhibited TNF-α secretion. In lipopolysaccharide-stimulated PBMCs from Pd-sensitized women showing high IFN-γ release, Pd nanoparticles inhibited TNF-α release and Pd salt IL-10 release. TNF-α and IFN-γ release and messenger RNA expression were correlated. Transmission electronmicroscopy demonstrated uptake of nanoparticles in the endocytic compartment and activation of autophagy. CONCLUSIONS: Palladium ions and nanoparticles exert different effects in vitro on the expression and release of cytokines.


Assuntos
Citocinas/sangue , Dermatite Alérgica de Contato/sangue , Leucócitos Mononucleares/metabolismo , Nanopartículas , Paládio/farmacologia , Adulto , Células Cultivadas , Citocinas/genética , Dermatite Alérgica de Contato/imunologia , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Interferon gama/sangue , Interferon gama/genética , Interleucina-10/sangue , Interleucina-10/genética , Interleucina-5/sangue , Interleucina-5/genética , Leucócitos Mononucleares/efeitos dos fármacos , Pessoa de Meia-Idade , Paládio/imunologia , RNA Mensageiro/sangue , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/genética , Adulto Jovem
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