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1.
Adv Healthc Mater ; : e2400522, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989725

RESUMO

In the pursuit of advancing neural tissue regeneration, biomaterial scaffolds have emerged as promising candidates, offering potential solutions for nerve disruptions. Among these scaffolds, multichannel hydrogels, characterized by meticulously designed micrometer-scale channels, stand out as instrumental tools for guiding axonal growth and facilitating cellular interactions. This study explores the innovative application of human amniotic membranes modified with methacryloyl domains (AMMA) in neural stem cell (NSC) culture. AMMA hydrogels, possessing a tailored softness resembling the physiological environment, are prepared in the format of multichannel scaffolds to simulate native-like microarchitecture of nerve tracts. Preliminary experiments on AMMA hydrogel films showcase their potential for neural applications, demonstrating robust adhesion, proliferation, and differentiation of NSCs without the need for additional coatings. Transitioning into the 3D realm, the multichannel architecture fosters intricate neuronal networks guiding neurite extension longitudinally. Furthermore, the presence of synaptic vesicles within the cellular arrays suggests the establishment of functional synaptic connections, underscoring the physiological relevance of the developed neuronal networks. This work contributes to the ongoing efforts to find ethical, clinically translatable, and functionally relevant approaches for regenerative neuroscience.

2.
Biomater Sci ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39034884

RESUMO

The ordered arrangement of cells and extracellular matrix facilitates the seamless transmission of electrical signals along axons in the spinal cord and peripheral nerves. Therefore, restoring tissue geometry is crucial for neural regeneration. This study presents a novel method using proteins derived from the human amniotic membrane, which is modified with photoresponsive groups, to produce cryogels with aligned porosity. Freeze-casting was used to produce cryogels with longitudinally aligned pores, while cryogels with randomly distributed porosity were used as the control. The cryogels exhibited remarkable injectability and shape-recovery properties, essential for minimally invasive applications. Different tendencies in proliferation and differentiation were evident between aligned and random cryogels, underscoring the significance of the scaffold's microstructure in directing the behaviour of neural stem cells (NSC). Remarkably, aligned cryogels facilitated extensive cellular infiltration and migration, contrasting with NSC cultured on isotropic cryogels, which predominantly remained on the scaffold's surface throughout the proliferation experiment. Significantly, the proliferation assay demonstrated that on day 7, the aligned cryogels contained eight times more cells compared to the random cryogels. Consistent with the proliferation experiments, NSC exhibited the ability to differentiate into neurons within the aligned scaffolds and extend neurites longitudinally. In addition, differentiation assays showed a four-fold increase in the expression of neural markers in the cross-sections of the aligned cryogels. Conversely, the random cryogels exhibited minimal presence of cell bodies and extensions. The presence of synaptic vesicles on the anisotropic cryogels indicates the formation of functional synaptic connections, emphasizing the importance of the scaffold's microstructure in guiding neuronal reconnection.

3.
ACS Nano ; 18(24): 15815-15830, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38833572

RESUMO

Amyloid-like fibrils are garnering keen interest in biotechnology as supramolecular nanofunctional units to be used as biomimetic platforms to control cell behavior. Recent insights into fibril functionality have highlighted their importance in tissue structure, mechanical properties, and improved cell adhesion, emphasizing the need for scalable and high-kinetics fibril synthesis. In this study, we present the instantaneous and bulk formation of amyloid-like nanofibrils from human platelet lysate (PL) using the ionic liquid cholinium tosylate as a fibrillating agent. The instant fibrillation of PL proteins upon supramolecular protein-ionic liquid interactions was confirmed from the protein conformational transition toward cross-ß-sheet-rich structures. These nanofibrils were utilized as building blocks for the formation of thin and flexible free-standing membranes via solvent casting to support cell self-aggregation. These PL-derived fibril membranes reveal a nanotopographically rough surface and high stability over 14 days under cell culture conditions. The culture of mesenchymal stem cells or tumor cells on the top of the membrane demonstrated that cells are able to adhere and self-organize in a three-dimensional (3D) spheroid-like microtissue while tightly folding the fibril membrane. Results suggest that nanofibril membrane incorporation in cell aggregates can improve cell viability and metabolic activity, recreating native tissues' organization. Altogether, these PL-derived nanofibril membranes are suitable bioactive platforms to generate 3D cell-guided microtissues, which can be explored as bottom-up strategies to faithfully emulate native tissues in a fully human microenvironment.


Assuntos
Plaquetas , Nanofibras , Humanos , Plaquetas/metabolismo , Plaquetas/química , Nanofibras/química , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Agregação Celular/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Amiloide/química , Amiloide/metabolismo , Membranas Artificiais
4.
Macromol Biosci ; : e2400227, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940700

RESUMO

The immune system is a pivotal player in determining tumor fate, contributing to the immunosuppressive microenvironment that supports tumor progression. Considering the emergence of biomaterials as promising platforms to mimic the tumor microenvironment, human platelet lysate (PLMA)-based hydrogel beads are proposed as 3D platforms to recapitulate the tumor milieu and recreate the synergistic tumor-macrophage communication. Having characterized the biomaterial-mediated pro-regenerative macrophage phenotype, an osteosarcoma spheroid encapsulated into a PLMA hydrogel bead is explored to study macrophage immunomodulation through paracrine signaling. The culture of PLMA-Tumor beads on the top of a 2D monolayer of macrophages reveals that tumor cells triggered morphologic and metabolic adaptations in macrophages. The cytokine profile, coupled with the upregulation of gene and protein anti-inflammatory biomarkers clearly indicates macrophage polarization toward an M2-like phenotype. Moreover, the increased gene expression of chemokines identified as pro-tumoral environmental regulators suggest a tumor-associated macrophage phenotype, exclusively stimulated by tumor cells. This pro-tumoral microenvironment is also found to enhance tumor invasiveness ability and proliferation. Besides providing a robust in vitro immunomodulatory tumor model that faithfully recreates the tumor-macrophage interplay, this human-based platform has the potential to provide fundamental insights into immunosuppressive signaling and predict immune-targeted response.

5.
Ann Bot ; 133(1): 183-212, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38109285

RESUMO

BACKGROUND: The sugar kelp Saccharina latissima is a Laminariales species widely distributed in the Northern Hemisphere. Its physiology and ecology have been studied since the 1960s, given its ecological relevance on western temperate coasts. However, research interest has been rising recently, driven mainly by reports of negative impacts of anthropogenically induced environmental change and by the increased commercial interest in cultivating the species, with several industrial applications for the resulting biomass. SCOPE: We used a variety of sources published between 2009 to May 2023 (but including some earlier literature where required), to provide a comprehensive review of the ecology, physiology, biochemical and molecular biology of S. latissima. In so doing we aimed to better understand the species' response to stressors in natural communities, but also inform the sustainable cultivation of the species. CONCLUSION: Due to its wide distribution, S. latissima has developed a variety of physiological and biochemical mechanisms to adjust to environmental changes, including adjustments in photosynthetic parameters, modulation of osmolytes and antioxidants, reprogramming of gene expression and epigenetic modifications, among others summarized in this review. This is particularly important because massive changes in the abundance and distribution of S. latissima have already been observed. Namely, presence and abundance of S. latissima has significantly decreased at the rear edges on both sides of the Atlantic, and increased in abundance at the polar regions. These changes were mainly caused by climate change and will therefore be increasingly evident in the future. Recent developments in genomics, transcriptomics and epigenomics have clarified the existence of genetic differentiation along its distributional range with implications in the fitness at some locations. The complex biotic and abiotic interactions unraveled here demonstrated the cascading effects the disappearance of a kelp forest can have in a marine ecosystem. We show how S. latissima is an excellent model to study acclimation and adaptation to environmental variability and how to predict future distribution and persistence under climate change.


Assuntos
Algas Comestíveis , Kelp , Laminaria , Kelp/genética , Ecossistema , Açúcares , Mudança Climática
7.
Front Chem ; 10: 1011186, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36238095

RESUMO

Water is the most important resource for all kind forms of live. It is a vital resource distributed unequally across different regions of the globe, with populations already living with water scarcity, a situation that is spreading due to the impact of climate change. The reversal of this tendency and the mitigation of its disastrous consequences is a global challenge posed to Humanity, with the scientific community assuming a major obligation for providing solutions based on scientific knowledge. This article reviews literature concerning the development of nanomaterials for water purification technologies, including collaborative scientific research carried out in our laboratory (nanoLAB@UA) framed by the general activities carried out at the CICECO-Aveiro Institute of Materials. Our research carried out in this specific context has been mainly focused on the synthesis and surface chemical modification of nanomaterials, typically of a colloidal nature, as well as on the evaluation of the relevant properties that arise from the envisaged applications of the materials. As such, the research reviewed here has been guided along three thematic lines: 1) magnetic nanosorbents for water treatment technologies, namely by using biocomposites and graphite-like nanoplatelets; 2) nanocomposites for photocatalysis (e.g., TiO2/Fe3O4 and POM supported graphene oxide photocatalysts; photoactive membranes) and 3) nanostructured substrates for contaminant detection using surface enhanced Raman scattering (SERS), namely polymers loaded with Ag/Au colloids and magneto-plasmonic nanostructures. This research is motivated by the firm believe that these nanomaterials have potential for contributing to the solution of environmental problems and, conversely, will not be part of the problem. Therefore, assessment of the impact of nanoengineered materials on eco-systems is important and research in this area has also been developed by collaborative projects involving experts in nanotoxicity. The above topics are reviewed here by presenting a brief conceptual framework together with illustrative case studies, in some cases with original research results, mainly focusing on the chemistry of the nanomaterials investigated for target applications. Finally, near-future developments in this research area are put in perspective, forecasting realistic solutions for the application of colloidal nanoparticles in water cleaning technologies.

8.
Biodivers Data J ; 10: e80798, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35437402

RESUMO

Background: Climate change has been increasing at an unprecedented rate in the last decades. Global warming has been causing a variety of impacts in marine ecosystems, including shifts in the geographical ranges of species. The north-western Iberian Peninsula coast is particularly interesting to study distribution shifts as it features a strong latitude thermal gradient, establishing a biogeographical transitional region where several cold- and warm-adapted species have their equatorward or poleward distributions. In the early 2000s, it appeared that, while warm-water species were already responding to warming, cold-water species did not display a coherent response. It is now necessary to gather up-to-date data on the distribution of the same group of species to understand if current patterns of change confirm or deny those observed back then, which may give us important clues about the mechanisms setting species limits in the area. New information: This study provides a fine-scale description of the occurrence of intertidal macroalgae species in the rocky shores of the north-western Iberian coast. Specifically, the spatial distribution and semi-quantitative abundance of 34 native and invasive species were assessed at 70 wave-exposed locations. This included 19 species of cold-water affinity, 10 species of warm-water affinity and five neutral species. When contrasted with historical observations, these new data can be used to quantify and map biodiversity change in the region, as well as help understanding the mechanisms constraining species distributions.

9.
Nat Med ; 28(4): 752-765, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35411077

RESUMO

Whole-brain radiotherapy (WBRT) is the treatment backbone for many patients with brain metastasis; however, its efficacy in preventing disease progression and the associated toxicity have questioned the clinical impact of this approach and emphasized the need for alternative treatments. Given the limited therapeutic options available for these patients and the poor understanding of the molecular mechanisms underlying the resistance of metastatic lesions to WBRT, we sought to uncover actionable targets and biomarkers that could help to refine patient selection. Through an unbiased analysis of experimental in vivo models of brain metastasis resistant to WBRT, we identified activation of the S100A9-RAGE-NF-κB-JunB pathway in brain metastases as a potential mediator of resistance in this organ. Targeting this pathway genetically or pharmacologically was sufficient to revert the WBRT resistance and increase therapeutic benefits in vivo at lower doses of radiation. In patients with primary melanoma, lung or breast adenocarcinoma developing brain metastasis, endogenous S100A9 levels in brain lesions correlated with clinical response to WBRT and underscored the potential of S100A9 levels in the blood as a noninvasive biomarker. Collectively, we provide a molecular framework to personalize WBRT and improve its efficacy through combination with a radiosensitizer that balances therapeutic benefit and toxicity.


Assuntos
Neoplasias Encefálicas , Melanoma , Neoplasias Encefálicas/secundário , Irradiação Craniana , Humanos , Melanoma/radioterapia
11.
Biodivers Data J ; 9: e72961, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720639

RESUMO

BACKGROUND: The unprecedented rates of current biodiversity loss have motivated a renewed interest in environmental and biodiversity monitoring. The need for sustained monitoring strategies has prompted not only the establisment of new long-term monitoring programmes, but also the rescue of data from historical or otherwise archived sources. Amongst the most valuable datasets are those containing information on intertidal systems, as they are particularly well suited for studying the biological effects of climate change. The Portuguese rocky coast is quite interesting for studying the effects of climate change on the distribution of species due to its geographical orientation, latitudinal patterns in temperature, species richness, species' distribution patterns and availability of historical information. This work aims at providing a comprehensive picture of the distribution and abundance of intertidal macro-invertebrates and macro-algae along the Portuguese rocky coast in the early 2000s. NEW INFORMATION: This study provides a description of the rocky shore intertidal biodiversity of the mainland Portuguese coast in the early 2000s. The spatial distribution and semi-quantitative abundance of a total of 238 taxa were assessed at 49 wave-exposed locations. These data provide a comprehensive baseline against which biodiversity changes can be effectively and objectively evaluated.

12.
Acta Biomater ; 134: 204-214, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34303015

RESUMO

To date, anticancer therapies with evidenced efficacy in preclinical models fail during clinical trials. The shortage of robust drug screening platforms that accurately predict patient's response underlie these misleading results. To provide a reliable platform for tumor drug discovery, we herein propose a relevant humanized 3D osteosarcoma (OS) model exploring the potential of methacryloyl platelet lysates (PLMA)-based hydrogels to sustain spheroid growth and invasion. The architecture and synergistic cell-microenvironment interaction of an invading tumor was recapitulated encapsulating spheroids in PLMA hydrogels, alone or co-cultured with osteoblasts and mesenchymal stem cells. The stem cells alignment toward OS spheroid suggested that tumor cells chemotactically attracted the surrounding stromal cells, which supported tumor growth and invasion into the hydrogels. The exposure of established models to doxorubicin revealed an improved drug resistance of PLMA-based models, comparing with scaffold-free spheroids. The proposed OS models highlighted the feasibility of PLMA hydrogels to support tumor invasion and recapitulate tumor-stromal cell crosstalk, demonstrating the potential of this 3D platform for complex tumor modelling. STATEMENT OF SIGNIFICANCE: Cell invasion mechanisms involved in tumor progression have been recapitulated in the field of 3D in vitro modeling, leveraging the great advance in biomimetic materials. In line with the growing interest in human-derived biomaterials, the aim of this study is to explore for the first time the potential of methacryloyl platelet lysates (PLMA)-based hydrogels to develop a humanized 3D osteosarcoma model to assess tumor invasiveness and drug sensitivity. By co-culturing tumor spheroids with human osteoblasts and human mesenchymal stem cells, this study demonstrated the importance of the synergistic tumor cell-microenvironment interaction in tumor growth, invasion and drug resistance. The established 3D osteosarcoma model highlighted the feasibility of PLMA hydrogels as a relevant 3D platform for complex tumor modelling.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Bioengenharia , Neoplasias Ósseas/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Hidrogéis , Osteossarcoma/tratamento farmacológico , Esferoides Celulares , Microambiente Tumoral
13.
Adv Sci (Weinh) ; 7(7): 1902398, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32274296

RESUMO

Fundamental physiologic and pathologic phenomena such as wound healing and cancer metastasis are typically associated with the migration of cells through adjacent extracellular matrix. In recent years, advances in biomimetic materials have supported the progress in 3D cell culture and provided biomedical tools for the development of models to study spheroid invasiveness. Despite this, the exceptional biochemical and biomechanical properties of human-derived materials are poorly explored. Human methacryloyl platelet lysates (PLMA)-based hydrogels are herein proposed as reliable 3D platforms to sustain in vivo-like cell invasion mechanisms. A systematic analysis of spheroid viability, size, and invasiveness is performed in three biomimetic materials: PLMA hydrogels at three different concentrations, poly(ethylene glycol) diacrylate, and Matrigel. Results demonstrate that PLMA hydrogels perfectly support the recapitulation of the tumor invasion behavior of cancer cell lines (MG-63, SaOS-2, and A549) and human bone-marrow mesenchymal stem cell spheroids. The distinct invasiveness ability of each cell type is reflected in the PLMA hydrogels and, furthermore, different mechanical properties produce an altered invasive behavior. The herein presented human PLMA-based hydrogels could represent an opportunity to develop accurate cell invasiveness models and open up new possibilities for humanized and personalized high-throughput screening and validation of anticancer drugs.

14.
Physiol Plant ; 168(1): 5-26, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31267544

RESUMO

The Arctic region is currently facing substantial environmental changes due to global warming. Melting glaciers cause reduced salinity environments in coastal Arctic habitats, which may be stressful for kelp beds. To investigate the responses of the kelp Saccharina latissima to the warming Arctic, we studied the transcriptomic changes of S. latissima from Kongsfjorden (Svalbard, Norway) over a 24-hour exposure to two salinities (Absolute Salinity [SA ] 20 and 30) after a 7-day pre-acclimation at three temperatures (0, 8 and 15°C). In addition, corresponding physiological data were assessed during an 11-days salinity/temperature experiment. Growth and maximal quantum yield for photosystem II fluorescence were positively affected by increased temperature during acclimation, whereas hyposalinity caused negative effects at the last day of treatment. In contrast, hyposalinity induced marked changes on the transcriptomic level. Compared to the control (8°C - SA 30), the 8°C - SA 20 exhibited the highest number of differentially expressed genes (DEGs), followed by the 0°C - SA 20. Comparisons indicate that S. latissima tends to convert its energy from primary metabolism (e.g. photosynthesis) to antioxidant activity under hyposaline stress. The increase in physiological performance at 15°C shows that S. latissima in the Arctic region can adjust and might even benefit from increased temperatures. However, in Arctic fjord environments its performance might become impaired by decreased salinity as a result of ice melting.


Assuntos
Aclimatação , Mudança Climática , Kelp/fisiologia , Phaeophyceae/fisiologia , Transcriptoma , Regiões Árticas , Fotossíntese , Complexo de Proteína do Fotossistema II/fisiologia , Salinidade , Estresse Fisiológico , Svalbard
15.
BMC Plant Biol ; 19(1): 513, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31775614

RESUMO

BACKGROUND: Kelps (Laminariales, Phaeophyceae) are brown macroalgae of utmost ecological, and increasingly economic, importance on temperate to polar rocky shores. Omics approaches in brown algae are still scarce and knowledge of their acclimation mechanisms to the changing conditions experienced in coastal environments can benefit from the application of RNA-sequencing. Despite evidence of ecotypic differentiation, transcriptomic responses from distinct geographical locations have, to our knowledge, never been studied in the sugar kelp Saccharina latissima so far. RESULTS: In this study we investigated gene expression responses using RNA-sequencing of S. latissima from environments with contrasting temperature and salinity conditions - Roscoff, in temperate eastern Atlantic, and Spitsbergen in the Arctic. Juvenile sporophytes derived from uniparental stock cultures from both locations were pre-cultivated at 8 °C and SA 30. Sporophytes acclimated to 0 °C, 8 °C and 15 °C were exposed to a low salinity treatment (SA 20) for 24 h. Hyposalinity had a greater impact at the transcriptomic level than the temperature alone, and its effects were modulated by temperature. Namely, photosynthesis and pigment synthesis were extensively repressed by low salinity at low temperatures. Although some responses were shared among sporophytes from the different sites, marked differences were revealed by principal component analysis, differential expression and GO enrichment. The interaction between low temperature and low salinity drove the largest changes in gene expression in sporophytes from Roscoff while specimens from Spitsbergen required more metabolic adjustment at higher temperatures. Moreover, genes related to cell wall adjustment were differentially expressed between Spitsbergen and Roscoff control samples. CONCLUSIONS: Our study reveals interactive effects of temperature and salinity on transcriptomic profiles in S. latissima. Moreover, our data suggest that under identical culture conditions sporophytes from different locations diverge in their transcriptomic responses. This is probably connected to variations in temperature and salinity in their respective environment of origin. The current transcriptomic results support the plastic response pattern in sugar kelp which is a species with several reported ecotypes. Our data provide the baseline for a better understanding of the underlying processes of physiological plasticity and may help in the future to identify strains adapted to specific environments and its genetic control.


Assuntos
Kelp/genética , Estresse Fisiológico , Transcriptoma , Aclimatação , Perfilação da Expressão Gênica , Fotossíntese , Filogeografia , Salinidade , Estresse Fisiológico/genética , Temperatura
16.
Sci Total Environ ; 682: 70-79, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31108270

RESUMO

Gold nanorods have shown to pose adverse effects to biota. Whether these effects may be potentiated through prolonged exposure has been rarely studied. Therefore, this work aimed at evaluating the effects of long-term exposure to sublethal levels of cetyltrimethylammonium bromide (CTAB) coated gold nanorods (Au-NR) on two freshwater microalgae: Chlorella vulgaris and Raphidocelis subcapitata. These algae were exposed to several concentrations of Au-NR for 72 h and, afterwards, to the corresponding EC5,72h, for growth, during 16 days. The sensitivity of the two algae to Au-NR was assessed at days 0, 4, 8, 12 and 16 (D0, D4, D8, D12 and D16, respectively) after a 72-h exposure to several concentrations of Au-NR. At the end of the assays, effects on yield and population growth rate were evaluated. Raphidocelis subcapitata was slightly more sensitive to Au-NR than C. vulgaris: EC50,72h,D0 for yield were 48.1 (35.3-60.9) and 70.5 (52.4-88.6) µg/L Au-NR, respectively while for population growth rate were above the highest tested concentrations (53 and 90 µg/L, respectively). For R. subcapitata the long-term exposure to Au-NR increased its sensitivity to this type of nanostructures. For C. vulgaris, a decrease on the effects caused by Au-NR occurred over time, with no significant effects being observed for yield or population growth rate at D12 and D16. The capping agent CTAB caused reductions in yield above 30% (D0) for both algae at the concentration matching the one at the highest Au-NR tested concentration. When exposed to CTAB, the highest inhibition values were 69% (D4) and 21.3% (D8) for R. subcapitata, and 64% (D12) and 21% (D16) to C. vulgaris, for yield and population growth rate, respectively. These results suggested long-term exposures should be included in ecological risk assessments since short-term standard toxicity may either under- or overestimate the risk posed by Au-NR.


Assuntos
Clorofíceas/efeitos dos fármacos , Coloide de Ouro/toxicidade , Microalgas/efeitos dos fármacos , Nanotubos/toxicidade , Poluentes Químicos da Água/toxicidade , Chlorella vulgaris/efeitos dos fármacos , Água Doce , Fatores de Tempo
17.
Cell Rep ; 27(4): 1277-1292.e7, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31018140

RESUMO

The brain is a major site of relapse for several cancers, yet deciphering the mechanisms of brain metastasis remains a challenge because of the complexity of the brain tumor microenvironment (TME). To define the molecular landscape of brain metastasis from intact tissue in vivo, we employ an RNA-sequencing-based approach, which leverages the transcriptome of xenografts and distinguishes tumor cell and stromal gene expression with improved sensitivity and accuracy. Our data reveal shifts in epithelial and neuronal-like lineage programs in malignant cells as they adapt to the brain TME and the reciprocal neuroinflammatory response of the stroma. We identify several transcriptional hallmarks of metastasis that are specific to particular regions of the brain, induced across multiple tumor types, and confirmed in syngeneic models and patient biopsies. These data may serve as a resource for exploring mechanisms of TME co-adaptation within, as well as across, different subtypes of brain metastasis.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/secundário , Inflamação/patologia , Neoplasias/patologia , Plasticidade Neuronal/genética , Células Estromais/patologia , Microambiente Tumoral/genética , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem da Célula , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Inflamação/genética , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Nus , Neoplasias/genética , Neoplasias/metabolismo , Células Estromais/metabolismo , Transcriptoma , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Nat Med ; 24(7): 1024-1035, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29892069

RESUMO

The brain microenvironment imposes a particularly intense selective pressure on metastasis-initiating cells, but successful metastases bypass this control through mechanisms that are poorly understood. Reactive astrocytes are key components of this microenvironment that confine brain metastasis without infiltrating the lesion. Here, we describe that brain metastatic cells induce and maintain the co-option of a pro-metastatic program driven by signal transducer and activator of transcription 3 (STAT3) in a subpopulation of reactive astrocytes surrounding metastatic lesions. These reactive astrocytes benefit metastatic cells by their modulatory effect on the innate and acquired immune system. In patients, active STAT3 in reactive astrocytes correlates with reduced survival from diagnosis of intracranial metastases. Blocking STAT3 signaling in reactive astrocytes reduces experimental brain metastasis from different primary tumor sources, even at advanced stages of colonization. We also show that a safe and orally bioavailable treatment that inhibits STAT3 exhibits significant antitumor effects in patients with advanced systemic disease that included brain metastasis. Responses to this therapy were notable in the central nervous system, where several complete responses were achieved. Given that brain metastasis causes substantial morbidity and mortality, our results identify a novel treatment for increasing survival in patients with secondary brain tumors.


Assuntos
Astrócitos/patologia , Neoplasias Encefálicas/secundário , Fator de Transcrição STAT3/metabolismo , Animais , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Sobrevivência Celular , Marcação de Genes , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Imunidade Inata , Camundongos , Fosforilação , Microambiente Tumoral
19.
Nat Med ; 24(9): 1481, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29921958

RESUMO

In the version of this article originally published, the names of three authors were incorrect. The authors were listed as "Coral Fustero-Torres", "Elena Pineiro" and "Melchor Sánchez-Martínez". Their respective names are "Coral Fustero-Torre", "Elena Piñeiro-Yáñez" and "Melchor Sanchez-Martinez". The errors have been corrected in the print, HTML and PDF versions of this article.

20.
Clin Epigenetics ; 10: 54, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29692867

RESUMO

Background: Periprostatic adipose tissue (PPAT) has been recognized to associate with prostate cancer (PCa) aggressiveness and progression. Here, we sought to investigate whether excess adiposity modulates the methylome of PPAT in PCa patients. DNA methylation profiling was performed in PPAT from obese/overweight (OB/OW, BMI > 25 kg m-2) and normal weight (NW, BMI < 25 kg m-2) PCa patients. Significant differences in methylated CpGs between OB/OW and NW groups were inferred by statistical modeling. Results: Five thousand five hundred twenty-six differentially methylated CpGs were identified between OB/OW and NW PCa patients with 90.2% hypermethylated. Four hundred eighty-three of these CpGs were found to be located at both promoters and CpG islands, whereas the representing 412 genes were found to be involved in pluripotency of stem cells, fatty acid metabolism, and many other biological processes; 14 of these genes, particularly FADS1, MOGAT1, and PCYT2, with promoter hypermethylation presented with significantly decreased gene expression in matched samples. Additionally, 38 genes were correlated with antigen processing and presentation of endogenous antigen via MHC class I, which might result in fatty acid accumulation in PPAT and tumor immune evasion. Conclusions: Results showed that the whole epigenome methylation profiles of PPAT were significantly different in OB/OW compared to normal weight PCa patients. The epigenetic variation associated with excess adiposity likely resulted in altered lipid metabolism and immune dysregulation, contributing towards unfavorable PCa microenvironment, thus warranting further validation studies in larger samples.


Assuntos
Tecido Adiposo/química , Metilação de DNA , Epigenômica/métodos , Obesidade/genética , Sobrepeso/genética , Neoplasias da Próstata/patologia , Idoso , Ilhas de CpG , Dessaturase de Ácido Graxo Delta-5 , Progressão da Doença , Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla , Humanos , Metabolismo dos Lipídeos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Projetos Piloto , Regiões Promotoras Genéticas , Neoplasias da Próstata/genética
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