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BACKGROUND: Breast cancer is the most common cancer, and the leading cause of cancer-related deaths, among females world-wide. Recent research suggests that extracellular vesicles (EVs) play a major role in the development of breast cancer metastasis. Axillary lymph node dissection (ALND) is a procedure in patients with known lymph node metastases, and after surgery large amounts of serous fluid are produced from the axilla. The overall aim was to isolate and characterize EVs from axillary serous fluid, and more specifically to determine if potential breast cancer biomarkers could be identified. METHODS: Lymphatic drain fluid was collected from 7 patients with breast cancer the day after ALND. EVs were isolated using size exclusion chromatography, quantified and detected by nanoparticle tracking analysis, electron microscopy, nano flow cytometry and western blot. The expression of 37 EV surface proteins was evaluated by flow cytometry using the MACSPlex Exosome kit. RESULTS: Lymphatic drainage exudate retrieved after surgery from all 7 patients contained EVs. The isolated EVs were positive for the typical EV markers CD9, CD63, CD81 and Flotillin-1 while albumin was absent, indicating low contamination from blood proteins. In total, 24 different EV surface proteins were detected. Eleven of those proteins were detected in all patients, including the common EV markers CD9, CD63 and CD81, cancer-related markers CD24, CD29, CD44 and CD146, platelet markers CD41b, CD42a and CD62p as well as HLA-DR/DP/DQ. Furthermore, CD29 and CD146 were enriched in Her2+ patients compared to patients with Her2- tumors. CONCLUSIONS: Lymphatic drainage exudate retrieved from breast cancer patients after surgery contains EVs that can be isolated using SEC isolation. The EVs have several cancer-related markers including CD24, CD29, CD44 and CD146, proteins of potential interest as biomarkers as well as to increase the understanding of the mechanisms of cancer biology.
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Biomarcadores Tumorais/análise , Neoplasias da Mama , Vesículas Extracelulares/química , Exsudatos e Transudatos/química , Linfonodos/patologia , Adulto , Idoso , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Excisão de Linfonodo , Pessoa de Meia-IdadeRESUMO
Degradation of extracellular matrix (ECM) in intervertebral disks (IVDs) during IVD degeneration plays a vital role in low back pain (LBP). In healthy IVDs, synthesis and degradation of ECM are kept in balance by matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs. MMPs are enzymes responsible for ECM degradation, and their expression levels are known to increase in degenerated disks. However, the exact pathophysiological concentration of MMP-1 in the degenerated disks of patients with chronic LBP has not been reported previously. Factors secreted by human mesenchymal stem cells (hMSCs) have shown positive results in cell therapy of degenerated disks. The aim of this study was to investigate the pathophysiological MMP-1 concentration (in ng/mL) in degenerated disk tissue and to evaluate if conditioned media (CM) from hMSCs could mitigate the effects of MMP-1 at the detected levels in a 3D in vitro disk cell (DC) pellet model. Tissue levels of MMP-1 were quantified in disk tissue collected from 6 chronic LBP patients undergoing surgery. DC pellet cultures were performed to investigate the effects of MMP-1 alone and the effects of conditioned media (CM) in the presence of MMP-1. MMP-1 was introduced in the pellets on day 14 at concentrations of 5, 50, or 100 ng/mL. The pellets were harvested on day 28 and evaluated for cell viability, proliferation, and ECM production. The mean concentration of MMP-1 in disk tissue was 151 ng/mL. Results from pellet cultures demonstrated a higher number of viable cells, glycosaminoglycan production, and ECM accumulation in the CM group even in the presence of MMP-1 compared to the controls. However, the level decreased with increasing MMP-1 concentration. The results demonstrated that CM has the ability to mitigate matrix degradation property of MMP-1 up to 50 ng/mL suggesting that CM could potentially be used to treat early stages of disk degeneration.
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Degeneração do Disco Intervertebral/enzimologia , Metaloproteinase 1 da Matriz/metabolismo , Células-Tronco Mesenquimais/metabolismo , Sinais Direcionadores de Proteínas , Adulto , Proliferação de Células , Sobrevivência Celular , Feminino , Fluorescência , Glicosaminoglicanos/metabolismo , Humanos , Disco Intervertebral/enzimologia , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/patologia , MasculinoRESUMO
MOTIVATION: Extracellular vesicles (EVs) are spherical bilayered proteolipids, harboring various bioactive molecules. Due to the complexity of the vesicular nomenclatures and components, online searches for EV-related publications and vesicular components are currently challenging. RESULTS: We present an improved version of EVpedia, a public database for EVs research. This community web portal contains a database of publications and vesicular components, identification of orthologous vesicular components, bioinformatic tools and a personalized function. EVpedia includes 6879 publications, 172 080 vesicular components from 263 high-throughput datasets, and has been accessed more than 65 000 times from more than 750 cities. In addition, about 350 members from 73 international research groups have participated in developing EVpedia. This free web-based database might serve as a useful resource to stimulate the emerging field of EV research. AVAILABILITY AND IMPLEMENTATION: The web site was implemented in PHP, Java, MySQL and Apache, and is freely available at http://evpedia.info.
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Biologia Computacional , Sistemas de Gerenciamento de Base de Dados , Bases de Dados Factuais , Exossomos/metabolismo , Espaço Extracelular/metabolismo , Software , Pesquisa Biomédica , Humanos , Interface Usuário-ComputadorRESUMO
In recent years there has been tremendous interest in both the basic biology and applications of extracellular vesicles (EVs) in translational cancer research. This includes a better understanding of their biogenesis and mechanisms of selective cargo packaging, their precise roles in horizontal communication, and their application as non-invasive biomarkers. The rapid advances in next-generation omics technologies are the driving forces for these discoveries. In this review, the authors focus on recent results of EV research in ovarian cancer. A deeper understanding of ovarian cancer-derived EVs, the types of cargo molecules and their biological roles in cancer growth, metastases and drug resistance, could have significant impact on the discovery of novel biomarkers and innovative therapeutics. Insights into the role of EVs in immune regulation could lead to novel approaches built on EV-based immunotherapy.
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Biomarcadores Tumorais/metabolismo , Vesículas Extracelulares/metabolismo , Imunoterapia/métodos , Neoplasias Ovarianas/diagnóstico , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Vesículas Extracelulares/imunologia , Feminino , Humanos , MicroRNAs/genética , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/terapia , Proteômica/métodosRESUMO
Exosomes are vesicles of endocytic origin released by many cells. These vesicles can mediate communication between cells, facilitating processes such as antigen presentation. Here, we show that exosomes from a mouse and a human mast cell line (MC/9 and HMC-1, respectively), as well as primary bone marrow-derived mouse mast cells, contain RNA. Microarray assessments revealed the presence of mRNA from approximately 1300 genes, many of which are not present in the cytoplasm of the donor cell. In vitro translation proved that the exosome mRNAs were functional. Quality control RNA analysis of total RNA derived from exosomes also revealed presence of small RNAs, including microRNAs. The RNA from mast cell exosomes is transferable to other mouse and human mast cells. After transfer of mouse exosomal RNA to human mast cells, new mouse proteins were found in the recipient cells, indicating that transferred exosomal mRNA can be translated after entering another cell. In summary, we show that exosomes contain both mRNA and microRNA, which can be delivered to another cell, and can be functional in this new location. We propose that this RNA is called "exosomal shuttle RNA" (esRNA).
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Comunicação Celular/genética , Epigênese Genética/genética , Exocitose/genética , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Vesículas Transportadoras/metabolismo , Animais , Linhagem Celular , Regulação da Expressão Gênica/genética , Humanos , Mastócitos/metabolismo , Mastócitos/ultraestrutura , Camundongos , MicroRNAs/genética , Biossíntese de Proteínas/genética , RNA Mensageiro/genética , Vesículas Transportadoras/genética , Vesículas Transportadoras/ultraestruturaRESUMO
BACKGROUND: Exosomes are 30-100 nm membrane vesicles of endocytic origin produced by numerous cells. They can mediate diverse biological functions, including antigen presentation. Exosomes have recently been shown to contain functional RNA, which can be delivered to other cells. Exosomes may thus mediate biological functions either by surface-to-surface interactions with cells, or by the delivery of functional RNA to cells. Our aim was therefore to determine the presence of RNA in exosomes from human saliva, plasma and breast milk and whether these exosomes can be taken up by macrophages. METHOD: Exosomes were purified from human saliva, plasma and breast milk using ultracentrifugation and filtration steps. Exosomes were detected by electron microscopy and examined by flow cytometry. Flow cytometry was performed by capturing the exosomes on anti-MHC class II coated beads, and further stain with anti-CD9, anti-CD63 or anti-CD81. Breast milk exosomes were further analysed for the presence of Hsc70, CD81 and calnexin by Western blot. Total RNA was detected with a Bioanalyzer and mRNA was identified by the synthesis of cDNA using an oligo (dT) primer and analysed with a Bioanalyzer. The uptake of PKH67-labelled saliva and breast milk exosomes by macrophages was examined by measuring fluorescence using flow cytometry and fluorescence microscopy. RESULTS: RNA was detected in exosomes from all three body fluids. A portion of the detected RNA in plasma exosomes was characterised as mRNA. Our result extends the characterisation of exosomes in healthy humans and confirms the presence of RNA in human saliva and plasma exosomes and reports for the first time the presence of RNA in breast milk exosomes. Our results also show that the saliva and breast milk exosomes can be taken up by human macrophages. CONCLUSIONS: Exosomes in saliva, plasma and breast milk all contain RNA, confirming previous findings that exosomes from several sources contain RNA. Furthermore, exosomes are readily taken up by macrophages, supporting the notion that exosomal RNA can be shuttled between cells.
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Exossomos/metabolismo , Macrófagos/metabolismo , Leite Humano/metabolismo , Plasma/metabolismo , RNA/metabolismo , Saliva/metabolismo , Antígenos CD/metabolismo , Calnexina/metabolismo , Exossomos/química , Proteínas de Choque Térmico HSC70/metabolismo , Humanos , Leite Humano/química , Plasma/química , RNA/análise , Saliva/química , Tetraspanina 28RESUMO
Staphylococcus aureus and Staphylococcus epidermidis are the bacteria that most frequently cause osteomyelitis. This study aimed to determine whether staphylococci isolated from osteomyelitis associated with septic loosening of orthopedic prostheses release extracellular vesicles (EVs) and, if so, to determine tentative immunomodulatory effects on the human monocytic cell line THP-1. EVs were isolated from bacterial cultures using filtration and ultracentrifugation and characterized by scanning electron microscopy, nanoparticle tracking analysis and Western Blot. The cytotoxic effect of EVs was analyzed by NucleoCounter and lactate dehydrogenase (LDH) analyses. Confocal laser scanning microscopy was employed to visualize the uptake of EVs by THP-1 cells. Activation of the transcription factor nuclear factor-κB (NF-κB) was determined in THP1-Blue™ NF-κB cells, and the gene expression and secretion of cytokines were determined by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. All investigated strains, irrespective of their biofilm formation ability, were able to secrete EVs in vitro. The S. aureus strains produced significantly more EVs than the S. epidermidis strains. Both S. aureus-derived EVs and S. epidermidis-derived EVs were internalized by THP-1 cells, upregulated Toll-like receptor 3 (TLR3) gene expression, activated NF-κB, and promoted the gene expression and secretion of interleukin (IL)-8, monocyte chemoattractant protein (MCP)-1, matrix metallopeptidase (MMP)-9 and IL-10. Whereas EVs from both staphylococcal species upregulated the proapoptotic DNA damage-inducible transcript 4 (DDIT4) gene and downregulated the antiapoptotic B-cell lymphoma 2 (Bcl-2) gene, cytolysis was preferentially induced in S. aureus EV-stimulated cells, possibly related to the expression of cytolytic proteins predominantly in S. aureus EVs. In conclusion, staphylococcal EVs possess potent cytolytic and immunomodulatory properties.
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Prótese Ancorada no Osso , Vesículas Extracelulares , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Staphylococcus epidermidisRESUMO
BACKGROUND: Extracellular vesicles (EVs) from human mesenchymal stem cells (hMSCs) are known to be mediators of intercellular communication and have been suggested as possible therapeutic agents in many diseases. Their potential use in intervertebral disc (IVD) degeneration associated with low back pain (LBP) is yet to be explored. Since LBP affects more than 85% of the western population resulting in high socioeconomic consequences, there is a demand for exploring new and possibly mini-invasive treatment alternatives. In this study, the effect of hMSC-derived small EVs (sEVs) on degenerated disc cells (DCs) isolated from patients with degenerative discs and chronic LBP was investigated in a 3D in vitro model. METHODS: hMSCs were isolated from bone marrow aspirate, and EVs were isolated from conditioned media of the hMSCs by differential centrifugation and filtration. 3D pellet cultures of DCs were stimulated with the sEVs at 5 × 1010 vesicles/ml concentration for 28 days and compared to control. The pellets were harvested at days 7, 14, and 28 and evaluated for cell proliferation, viability, ECM production, apoptotic activity, chondrogenesis, and cytokine secretions. RESULTS: The findings demonstrated that treatment with sEVs from hMSCs resulted in more than 50% increase in cell proliferation and decrease in cellular apoptosis in degenerated DCs from this patient group. ECM production was also observed as early as in day 7 and was more than three times higher in the sEV-treated DC pellets compared to control cultures. Further, sEV treatment suppressed secretion of MMP-1 in the DCs. CONCLUSION: hMSC-derived sEVs improved cell viability and expedited chondrogenesis in DCs from degenerated IVDs. These findings open up for new tissue regeneration treatment strategies to be developed for degenerative disorders of the spine.
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Vesículas Extracelulares , Degeneração do Disco Intervertebral , Disco Intervertebral , Células-Tronco Mesenquimais , Técnicas de Cultura de Células , Condrogênese , Humanos , Degeneração do Disco Intervertebral/terapiaRESUMO
An amendment to this paper has been published and can be accessed via the original article.
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Mesenchymal stem cells (MSCs) have important roles during osseointegration. This study determined (i) if MSC-derived extracellular vesicles (EVs)/exosomes can be immobilized on titanium (Ti) surfaces and influence the behavior of MSCs, (ii) if the response is differentially affected by EVs from expanded vs differentiated MSCs and (iii) if the EV protein cargos predict the functional features of the exosomes. EVs secreted by human adipose-derived MSCs were isolated by ultracentrifugation and analyzed using nanoparticle tracking analysis, Western blotting and relative quantitative mass spectrometry. Fluorescence microscopy, scanning electron microscopy, cell counting assay and quantitative polymerase chain reaction were used to analyze MSC adhesion, proliferation and differentiation. Exosome immobilization on Ti promoted MSC adhesion and spreading after 24â¯h and proliferation after 3 and 6 days, irrespective of whether the exosomes were obtained from expansion or differentiation conditions. Immobilized exosomes upregulated stromal cell-derived factor (SDF-1α) gene expression. Cell adhesion molecules and signaling molecules were abundant in the exosomal proteome. The predicted functions of the equally-abundant proteins in both exosome types were in line with the observed biological effects mediated by the exosomes. Thus, exosomes derived from MSCs and immobilized on Ti surfaces interact with MSCs and rapidly promote MSC adhesion and proliferation. These findings provide a novel route for modification of titanium implant surfaces.
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Diferenciação Celular , Exossomos , Células-Tronco Mesenquimais , Titânio , Humanos , Osseointegração , Transdução de SinaisRESUMO
We describe a second-generation deficiency kit for Drosophila melanogaster composed of molecularly mapped deletions on an isogenic background, covering approximately 77% of the Release 5.1 genome. Using a previously reported collection of FRT-bearing P-element insertions, we have generated 655 new deletions and verified a set of 209 deletion-bearing fly stocks. In addition to deletions, we demonstrate how the P elements may also be used to generate a set of custom inversions and duplications, particularly useful for balancing difficult regions of the genome carrying haplo-insufficient loci. We describe a simple computational resource that facilitates selection of appropriate elements for generating custom deletions. Finally, we provide a computational resource that facilitates selection of other mapped FRT-bearing elements that, when combined with the DrosDel collection, can theoretically generate over half a million precisely mapped deletions.
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Aberrações Cromossômicas , Elementos de DNA Transponíveis , Drosophila melanogaster/genética , Genoma , Deleção de Sequência , Animais , Dados de Sequência MolecularRESUMO
Human mesenchymal stem cell (hMSC)-derived exosomes have shown regenerative effects, but their role in osteogenesis and the underlying mechanism are yet to be determined. In this study, we examined the time-course secretion of exosomes by hMSCs during the entire process of osteogenic differentiation. Exosomes derived from hMSCs in various stages of osteogenic differentiation committed homotypic cells to differentiate towards osteogenic lineage, but only exosomes from late stages of osteogenic differentiation induced extracellular matrix mineralisation. Exosomes from expansion and early and late stages of osteogenic differentiation were internalised by a subpopulation of hMSCs. MicroRNA profiling revealed a set of differentially expressed exosomal microRNAs from the late stage of osteogenic differentiation, which were osteogenesis related. Target prediction demonstrated that these microRNAs enriched pathways involved in regulation of osteogenic differentiation and general mechanisms how exosomes exert their functions, such as "Wnt signalling pathway" and "endocytosis". Taken together, the results show that MSCs secrete exosomes with different biological properties depending on differentiation stage of their parent cells. The exosomal cargo transferred from MSCs in the late stage of differentiation induces osteogenic differentiation and mineralisation. Moreover, it is suggested that the regulatory effect on osteogenesis by exosomes is at least partly exerted by exosomal microRNA.
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Exossomos/genética , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Osteogênese/genética , Fosfatase Alcalina/metabolismo , Cálcio/metabolismo , Diferenciação Celular/genética , Células Cultivadas , Exossomos/metabolismo , Exossomos/ultraestrutura , Perfilação da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Microscopia Eletrônica de Transmissão , Transdução de Sinais/genéticaRESUMO
Monocytes and mesenchymal stem cells (MSC) are evident at the implants during early healing. However, when coexisting, their interactions at different implants have not been determined. This study uses an in vitro system, consisting of monoculture and direct co-cultures of monocytes and MSC on screw-shaped machined and oxidized titanium implants in combination with scanning electron microscopy, enzyme-linked immunosorbent assay, flow cytometry, cell sorting, and quantitative polymerase chain reaction. The cell-specific adhesion and gene expression of monocytes and MSC was determined. After 24 hr, the coexistence of monocytes and MSC in co-culture led to equal proportions of adherent monocytes and MSC, irrespective of the implant type. In contrast, higher number of adherent monocytes than MSC was found on the oxidized implant in monoculture. Quantitative polymerase chain reaction analysis of fluorescent activated cell sorting-sorted cells revealed up-regulation of interleukin-1beta, in monocytes, and interleukin-1beta and C-X-C chemokine receptor type 4, in MSC, when the cell types coexisted compared with monocultures. Further, in co-culture, the expression of bone morphogenetic protein-2, stromal cell-derived factor 1, and integrin-ß1 was enhanced in the implant-adherent MSC, but not monocytes. It is concluded that during the first 24 hr in an in vitro static condition, the effect of co-culture of monocytes and MSC was more prominent than the effect of the implant surface properties. The results indicate that the coexistence of monocytes and MSC on an implant alters the adhesion and expression of some genes compared with when each cell type existed alone. Further, the results show that the gene expression of major growth and recruitment factors is mainly enhanced in the implant-adherent MSC in contrast to implant-adherent monocytes in co-culture.
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Regulação da Expressão Gênica , Implantes Experimentais , Teste de Materiais , Células-Tronco Mesenquimais/metabolismo , Monócitos/metabolismo , Adesão Celular , Humanos , Células-Tronco Mesenquimais/citologia , Monócitos/citologiaRESUMO
Extracellular vesicles (EVs) are heterogeneous populations of nano- and micro-sized vesicles secreted by various cell types. There is mounting evidence that EVs have widespread roles in transporting proteins, lipids, and nucleic acids between cells and serve as mediators of intercellular communication. EVs secreted from stem cells could function as paracrine factors, and appear to mimic and recapitulate several features of their secreting cells. EV-mediated transport of regulatory RNAs provides a novel source of trans-regulation between cells. As such, stem cells have evolved unique forms of paracrine mechanisms for recapitulating their potencies with specialized functions by transporting non-coding RNAs (ncRNAs) via EVs. This includes the dissemination of stem cell-derived EV-ncRNAs and their regulatory effects elicited in differentiation, self-renewal, pluripotency, and the induction of reparative programs. Here, we summarize and discuss the therapeutic effects of mesenchymal stem cell-derived EV-ncRNAs in the induction of intrinsic regenerative programs elicited through regulating several mechanisms. Among them, most noticeable are the EV-mediated enrichment of ncRNAs at the injury sites contributing the regulation of matrix remodeling, epithelial mesenchymal transitions, and attraction of fibroblasts. Additionally, we emphasize EV-mediated transmission of anti-inflammatory RNAs from stem cells to injury site that potentially orchestrate the resolution of the inflammatory responses and immune alleviation to better facilitate healing processes. Collectively, this knowledge indicates a high value and potential of EV-mediated RNA-based therapeutic approaches in regenerative medicine.
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Stem cells are proposed to continuously secrete trophic factors that potentially serve as mediators of autocrine and paracrine activities, associated with reprogramming of the tumor microenvironment, tissue regeneration, and repair. Hitherto, significant efforts have been made to understand the level of underlying paracrine activities influenced by stem cell secreted trophic factors, as little is known about these interactions. Recent findings, however, elucidate this role by reporting the effects of stem cell derived extracellular vesicles (EVs) that mimic the phenotypes of the cells from which they originate. Exchange of genetic information utilizing persistent bidirectional communication mediated by stem cell-EVs could regulate stemness, self-renewal, and differentiation in stem cells and their subpopulations. This review therefore discusses stem cell-EVs as evolving communication factors in stem cell biology, focusing on how they regulate cell fates by inducing persistent and prolonged genetic reprogramming of resident cells in a paracrine fashion. In addition, we address the role of stem cell-secreted vesicles in shaping the tumor microenvironment and immunomodulation and in their ability to stimulate endogenous repair processes during tissue damage. Collectively, these functions ensure an enormous potential for future therapies.
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We describe a collection of P-element insertions that have considerable utility for generating custom chromosomal aberrations in Drosophila melanogaster. We have mobilized a pair of engineered P elements, p[RS3] and p[RS5], to collect 3243 lines unambiguously mapped to the Drosophila genome sequence. The collection contains, on average, an element every 35 kb. We demonstrate the utility of the collection for generating custom chromosomal deletions that have their end points mapped, with base-pair resolution, to the genome sequence. The collection was generated in an isogenic strain, thus affording a uniform background for screens where sensitivity to genetic background is high. The entire collection, along with a computational and genetic toolbox for designing and generating custom deletions, is publicly available. Using the collection it is theoretically possible to generate >12,000 deletions between 1 bp and 1 Mb in size by simple eye color selection. In addition, a further 37,000 deletions, selectable by molecular screening, may be generated. We are now using the collection to generate a second-generation deficiency kit that is precisely mapped to the genome sequence.
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Aberrações Cromossômicas , Elementos de DNA Transponíveis/genética , Drosophila melanogaster/genética , Animais , Técnicas Genéticas , Mutagênese Insercional/métodosRESUMO
OBJECTIVE: Macrophage-mediated oxidation of low-density lipoprotein (LDL) by enzymes, such as the lipoxygenases, is considered of major importance for the formation of oxidized LDL during atherogenesis. Macrophages have been identified in hypoxic areas in atherosclerotic plaques. METHODS AND RESULTS: To investigate the role of hypoxia in macrophage-mediated LDL oxidation, we incubated human monocyte-derived macrophages with LDL under normoxic (21% O2) or hypoxic (0% O2) conditions. The results showed that hypoxic macrophages oxidized LDL to a significantly higher extent than normoxic cells. Interestingly, the mRNA and protein expression of 15-lipoxygenase-2 (15-LOX-2) as well as the activity of this enzyme are elevated in macrophages incubated at hypoxia. Both the unspliced 15-LOX-2 and the spliced variant 15-LOX-2sv-a are found in macrophages. In addition, 15-LOX-2 was identified in carotid plaques in some macrophage-rich areas but was only expressed at low levels in nondiseased arteries. CONCLUSIONS: In summary, these observations show for the first time that 15-LOX-2 is expressed in hypoxic macrophages and in atherosclerotic plaques and suggest that 15-LOX-2 may be one of the factors involved in macrophage-mediated LDL oxidation at hypoxia.
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Araquidonato 15-Lipoxigenase/biossíntese , Hipóxia/enzimologia , Hipóxia/patologia , Lipoproteínas LDL/metabolismo , Macrófagos/enzimologia , Processamento Alternativo/genética , Araquidonato 15-Lipoxigenase/genética , Araquidonato 15-Lipoxigenase/imunologia , Arteriosclerose/enzimologia , Arteriosclerose/metabolismo , Arteriosclerose/patologia , Artérias Carótidas/enzimologia , Artérias Carótidas/patologia , Células Cultivadas , Ativação Enzimática/genética , Éxons/genética , Variação Genética/genética , Humanos , Imuno-Histoquímica/métodos , Macrófagos/citologia , Artéria Torácica Interna/fisiologia , Oxirredução , Deleção de Sequência/genéticaRESUMO
Bone development and regeneration is associated with the Wnt signaling pathway that, according to literature, can be modulated by lithium ions (Li+). The aim of this study was to evaluate the gene expression profile during peri-implant healing of poly(lactic-co-glycolic acid) (PLGA) implants with incorporated Li+, while PLGA without Li+ was used as control, and a special attention was then paid to the Wnt signaling pathway. The implants were inserted in rat tibia for 7 or 28 days and the gene expression profile was investigated using a genome-wide microarray analysis. The results were verified by qPCR and immunohistochemistry. Histomorphometry was used to evaluate the possible effect of Li+ on bone regeneration. The microarray analysis revealed a large number of significantly differentially regulated genes over time within the two implant groups. The Wnt signaling pathway was significantly affected by Li+, with approximately 34% of all Wnt-related markers regulated over time, compared to 22% for non-Li+ containing (control; Ctrl) implants. Functional cluster analysis indicated skeletal system morphogenesis, cartilage development and condensation as related to Li+. The downstream Wnt target gene, FOSL1, and the extracellular protein-encoding gene, ASPN, were significantly upregulated by Li+ compared with Ctrl. The presence of ß-catenin, FOSL1 and ASPN positive cells was confirmed around implants of both groups. Interestingly, a significantly reduced bone area was observed over time around both implant groups. The presence of periostin and calcitonin receptor-positive cells was observed at both time points. This study is to the best of the authors' knowledge the first report evaluating the effect of a local release of Li+ from PLGA at the fracture site. The present study shows that during the current time frame and with the present dose of Li+ in PLGA implants, Li+ is not an enhancer of early bone growth, although it affects the Wnt signaling pathway.
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Regeneração Óssea/efeitos dos fármacos , Perfilação da Expressão Gênica , Ácido Láctico/química , Lítio/farmacologia , Ácido Poliglicólico/química , Próteses e Implantes , Tíbia/fisiologia , Via de Sinalização Wnt , Animais , Lítio/administração & dosagem , Masculino , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Tíbia/efeitos dos fármacos , Tíbia/cirurgia , Tíbia/ultraestrutura , Proteínas Wnt/metabolismoRESUMO
The knowledge gained from comprehensive profiling projects that aim to define the complex genomic alterations present within cancers will undoubtedly improve our ability to detect and treat those diseases, but the influence of these resources on our understanding of basic cancer biology is still to be demonstrated. Extracellular vesicles have gained considerable attention in past years, both as mediators of intercellular signalling and as potential sources for the discovery of novel cancer biomarkers. In general, research on extracellular vesicles investigates either the basic mechanism of vesicle formation and cargo incorporation, or the isolation of vesicles from available body fluids for biomarker discovery. A deeper understanding of the cargo molecules present in extracellular vesicles obtained from patients with urogenital cancers, through high-throughput proteomics or genomics approaches, will aid in the identification of novel diagnostic and prognostic biomarkers, and can potentially lead to the discovery of new therapeutic targets.
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Biomarcadores Tumorais/urina , Carcinoma de Células Renais/diagnóstico , Micropartículas Derivadas de Células/química , Exossomos/química , Neoplasias Renais/diagnóstico , Neoplasias da Próstata/diagnóstico , Vesículas Secretórias/química , Neoplasias da Bexiga Urinária/diagnóstico , Biomarcadores Tumorais/sangue , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/urina , Micropartículas Derivadas de Células/genética , Micropartículas Derivadas de Células/metabolismo , Exossomos/genética , Exossomos/metabolismo , Genômica , Humanos , Neoplasias Renais/genética , Neoplasias Renais/urina , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Proteômica , Vesículas Secretórias/genética , Vesículas Secretórias/metabolismo , Sêmen/química , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/urinaRESUMO
BACKGROUND: Patterning medical devices at the nanoscale level enables the manipulation of cell behavior and tissue regeneration, with topographic features recognized as playing a significant role in the osseointegration of implantable devices. METHODS: In this study, we assessed the ability of titanium-coated hemisphere-like topographic nanostructures of different sizes (approximately 50, 100, and 200 nm) to influence the morphology, proliferation, and osteogenic differentiation of human mesenchymal stem cells (hMSCs). RESULTS: We found that the proliferation and osteogenic differentiation of hMSCs was influenced by the size of the underlying structures, suggesting that size variations in topographic features at the nanoscale level, independently of chemistry, can be exploited to control hMSC behavior in a size-dependent fashion. CONCLUSION: Our studies demonstrate that colloidal lithography, in combination with coating technologies, can be exploited to investigate the cell response to well defined nanoscale topography and to develop next-generation surfaces that guide tissue regeneration and promote implant integration.