170 research outputs found

    The Emerging Roles of Extracellular Vesicles in Osteosarcoma

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    Extracellular vesicles (EVs) are heterogeneous nanosized vesicles that are constitutively released by virtually all types of cells. They have been isolated in almost all body fluids. EVs cargo consists of various molecules (nucleic acids, proteins, lipids, and metabolites), that can be found on EVs surface and/or in their lumen. EVs structure confer stability and allow the transfer of their cargo to specific cell types over a distance. EVs play a critical role in intercellular communication in physiological and pathological settings. The broadening of knowledge on EVs improved our comprehension of cancer biology as far as tumor development, growth, metastasis, chemoresistance, and treatment are concerned. Increasing evidences suggest that EVs have a significant role in osteosarcoma (OS) development, progression, and metastatic process. The modulation of inflammatory communication pathways by EVs plays a critical role in OS and in other bone-related pathological conditions such as osteoarthritis and rheumatoid arthritis. In this review we describe the emerging data on the role of extracellular vesicles in osteosarcoma and discuss the effects and function of OS-derived EVs focusing on their future applicability in clinical practice

    Debugging reversibile di un frammento del linguaggio C

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    Questo elaborato descrive lo sviluppo di un debugger reversibile per un frammento del linguaggio C, mostrando come la funzione di reversibilità migliori l'efficienza della fase di debugging. Particolare enfasi è data alle strutture dati utilizzate sia per il debugger sia per il riconoscimento del linguaggio C. Infine, dopo aver spiegato brevemente la storia dell'applicazione della reversibilità ai debugger, ne viene spiegata nel dettaglio l'implementazione

    Tecniche di visione artificiale per la guida autonoma

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    Con questo elaborato si vuole mostrare qual è attualmente lo stato dell’arte per quanto riguarda la guida autonoma e fare una panoramica delle varie metodologie utilizzate all’interno di questo ambito. Viene mostrato all’interno del secondo capitolo tutto ciò che serve per poter attuare tecniche di guida autonoma, partendo dai vari sensori fino alle tecniche per farli lavorare al meglio tra di loro. Nel terzo capitolo vengono analizzate le varie tecniche per poter effettuare il rilevamento degli ostacoli e più in generale come vengono gestiti i vari oggetti presenti nello spazio circostante. Si conclude con il quarto capitolo, che mostra i principali metodi di apprendimento end-to-end, ovvero i metodi che forniscono le prestazioni migliori all’interno di questo ambito. Infine, il capitolo cinque riassume le principali conclusioni di questo lavoro di rassegna e discute possibili sviluppi futuri

    FT-IR Spectral Signature of Sensitive and Multidrug-Resistant Osteosarcoma Cell-Derived Extracellular Nanovesicles

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    Osteosarcoma (OS) is the most common primary bone cancer in children and adolescents. Despite aggressive treatment regimens, the outcome is unsatisfactory, and multidrug resistance (MDR) is a pivotal process in OS treatment failure. OS-derived extracellular vesicles (EVs) promote drug resistance to chemotherapy and target therapy through different mechanisms. The aim of this study was to identify subpopulations of osteosarcoma-EVs by Fourier transform infrared spectroscopy (FT-IR) to define a specific spectral signature for sensitive and multidrug-resistant OS-derived EVs. EVs were isolated from sensitive and MDR OS cells as well as from mesenchymal stem cells by differential centrifugation and ultracentrifugation. EVs size, morphology and protein expression were characterized. FT-IR/ATR of EVs spectra were acquired in the region of 400-4000 cm(-1) (resolution 4 cm(-1), 128 scans). The FT-IR spectra obtained were consistently different in the EVs compared to cells from which they originate. A specific spectral signature, characterized by a shift and a new band (1601 cm(-1)), permitted to clearly distinguish EVs isolated by sensitive and multidrug-resistant OS cells. Our data suggest that FT-IR spectroscopy allows to characterize and define a specific spectral signature for sensitive and MDR OS-derived EVs

    Extracellular nanovesicles secreted by human osteosarcoma cells promote angiogenesis

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    Angiogenesis involves a number of different players among which extracellular nanovesicles (EVs) have recently been proposed as an efficient cargo of pro-angiogenic mediators. Angiogenesis plays a key role in osteosarcoma (OS) development and progression. Acidity is a hallmark of malignancy in a variety of cancers, including sarcomas, as a result of an increased energetic metabolism. The aim of this study was to investigate the role of EVs derived from osteosarcoma cells on angiogenesis and whether extracellular acidity, generated by tumor metabolism, could influence EVs activity. For this purpose, we purified and characterized EVs from OS cells maintained at either acidic or neutral pH. The ability of EVs to induce angiogenesis was assessed in vitro by endothelial cell tube formation and in vivo using chicken chorioallantoic membrane. Our findings demonstrated that EVs derived from osteosarcoma cells maintained either in acidic or neutral conditions induced angiogenesis. The results showed that miRNA and protein content of EVs cargo are correlated with pro-angiogenic activity and this activity is increased by the acidity of tumor microenvironment. This study provides evidence that EVs released by human osteosarcoma cells act as carriers of active angiogenic stimuli that are able to promote endothelial cell functions relevant to angiogenesis

    MIcrogreens: Functional food with antiproliferative cancer properties influenced by light

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    The anti-proliferative/pro-oxidant efficacy of green pea, soybean, radish, Red Rambo radish, and rocket microgreens, cultivated under either fluorescent lighting (predominant spectral peaks in green and orange) or combination light-emitting diode (LED, predominant spectral peak in blue) was investigated using Ewing sarcoma lines, RD-ES and A673, respectively. All aqueous microgreen extracts significantly reduced cell proliferation (cancer prevention effect) to varying extents in two-dimensional sarcoma cell cultures. The effect of the polyphenol fraction in the aqueous food matrix was unrelated to total polyphenol content, which differed between species and light treatment. Only Pisum sativum (LED-grown) extracts exercised anti-proliferative and pro-apoptotic effects in both three-dimensional RD-ES and A673 spheroids (early tumor progression prevention), without cytotoxic effects on healthy L929 fibroblasts. A similar anti-tumor effect of Red Rambo radish (LED and fluorescent-grown) was evident only in the RD-ES spheroids. Aside from the promising anti-tumor potential of the polyphenol fraction of green pea microgreens, the latter also displayed favorable growth quality parameters, along with radish, under both light treatments over the 10 day cultivation period

    Exosomes: Novel effectors of human platelet lysate activity

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    Despite the popularity of platelet-rich plasma (PRP) and platelet lysate (PL) in orthopaedic practice, the mechanism of action and the effectiveness of these therapeutic tools are still controversial. So far, the activity of PRP and PL has been associated with different growth factors (GF) released during platelet degranulation. This study, for the first time, identifies exosomes, nanosized vesicles released in the extracellular compartment by a number of elements, including platelets, as one of the effectors of PL activity. Exosomes were isolated from human PL by differential ultracentrifugation, and analysed by electron microscopy and Western blotting. Bone marrow stromal cells (MSC) treated with three different exosome concentrations (0.6 μg, 5 μg and 50 μg) showed a significant, dose-dependent increase in cell proliferation and migration compared to the control. In addition, osteogenic differentiation assays demonstrated that exosome concentration differently affected the ability of MSC to deposit mineralised matrix. Finally, the analysis of exosome protein content revealed a higher amount of basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF-BB) and transforming growth factor beta 1 (TGF-β1) as compared to PL. In regards to RNA content, an enrichment of small RNAs in exosomes as compared to donor platelets has been found. These results suggest that exosomes consistently contribute to PL activity and could represent an advantageous nanodelivery system for cell-free regeneration therapies

    Sequential Combination of Cognitive-Behavioral Treatment and Well-Being Therapy in Depressed Patients with Acute Coronary Syndromes: A Randomized Controlled Trial (TREATED-ACS Study)

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    Introduction: Randomized controlled trials (RCT) of psychotherapeutic interventions have addressed depression and demoralization associated with acute coronary syndromes (ACS). The present trial introduces psychological well-being, an increasingly recognized factor in cardiovascular health, as a therapeutic target. Objective: This study was designed to determine whether the sequential combination of cognitive-behavioral therapy (CBT) and well-being therapy (WBT) may yield more favorable outcomes than an active control group (clinical management; CM) and to identify subgroups of patients at greater risk for cardiac negative outcomes. Methods: This multicenter RCT comparedCBT/WBT sequential combination versus CM, with up to 30 months of follow-up. One hundred consecutive depressed and/or demoralized patients (out of 740 initially screened by cardiologists after a first episode of ACS) were randomized to CBT/WBT associated with lifestyle suggestions (n = 50) and CM (n = 50). The main outcome measures included: severity of depressive symptoms according to the Clinical Interview for Depression, changes in subclinical psychological distress, well-being, and biomarkers, and medical complications and events. Results: CBT/WBT sequential combination was associated with a significant improvement in depressive symptoms compared to CM. In both groups, the benefits persisted at follow-up, even though the differences faded. Treatment was also related to a significant amelioration of biomarkers (platelet count, HDL, and D-dimer), whereas the 2 groups showed similar frequencies of adverse cardiac events. Conclusions: Addressing psychological well-being in the psychotherapeutic approach to ACS patients with depressive symptoms was found to entail important clinical benefits. It is argued that lifestyle changes geared toward cardiovascular health may be facilitated by a personalized approach that targets well-being

    Blocking tumor-educated MSC paracrine activity halts osteosarcoma progression

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    Purpose: Human osteosarcoma is a genetically heterogeneous bone malignancy with poor prognosis despite the employment of aggressive chemotherapy regimens. Because druggable driver mutations have not been established, dissecting the interactions between osteosarcoma cells and supporting stroma may provide insights into novel therapeutic targets.Experimental Design: By using a bioluminescent orthotopic xenograft mouse model of osteosarcoma, we evaluated the effect of tumor extracellular vesicle (EV)-educated mesenchymal stem cells (TEMSC) on osteosarcoma progression. Characterization and functional studies were designed to assess the mechanisms underlying MSC education. Independent series of tissue specimens were analyzed to corroborate the preclinical findings, and the composition of patient serum EVs was analyzed after isolation with size-exclusion chromatography.Results: We show that EVs secreted by highly malignant osteosarcoma cells selectively incorporate a membrane-associated form of TGFβ, which induces proinflammatory IL6 production by MSCs. TEMSCs promote tumor growth, accompanied with intratumor STAT3 activation and lung metastasis formation, which was not observed with control MSCs. Importantly, intravenous administration of the anti-IL6 receptor antibody tocilizumab abrogated the tumor-promoting effects of TEMSCs. RNA-seq analysis of human osteosarcoma tissues revealed a distinct TGFβ-induced prometastatic gene signature. Tissue microarray immunostaining indicated active STAT3 signaling in human osteosarcoma, consistent with the observations in TEMSC-treated mice. Finally, we isolated pure populations of EVs from serum and demonstrated that circulating levels of EV-associated TGFβ are increased in osteosarcoma patients.Conclusions: Collectively, our findings suggest that TEMSCs promote osteosarcoma progression and provide the basis for testing IL6- and TGFβ-blocking agents as new therapeutic options for osteosarcoma patients

    Blocking Tumor-Educated MSC Paracrine Activity Halts Osteosarcoma Progression

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    Purpose: Human osteosarcoma is a genetically heterogeneous bone malignancy with poor prognosis despite the employment of aggressive chemotherapy regimens. Because druggable driver mutations have not been established, dissecting the interactions between osteosarcoma cells and supporting stroma may provide insights into novel therapeutic targets.Experimental Design: By using a bioluminescent orthotopic xenograft mouse model of osteosarcoma, we evaluated the effect of tumor extracellular vesicle (EV)-educated mesenchymal stem cells (TEMSC) on osteosarcoma progression. Characterization and functional studies were designed to assess the mechanisms underlying MSC education. Independent series of tissue specimens were analyzed to corroborate the preclinical findings, and the composition of patient serum EVs was analyzed after isolation with size-exclusion chromatography.Results: We show that EVs secreted by highly malignant osteosarcoma cells selectively incorporate a membrane-associated form of TGF\u3b2, which induces proinflammatory IL6 production by MSCs. TEMSCs promote tumor growth, accompanied with intratumor STAT3 activation and lung metastasis formation, which was not observed with control MSCs. Importantly, intravenous administration of the anti-IL6 receptor antibody tocilizumab abrogated the tumor-promoting effects of TEMSCs. RNA-seq analysis of human osteosarcoma tissues revealed a distinct TGF\u3b2-induced prometastatic gene signature. Tissue microarray immunostaining indicated active STAT3 signaling in human osteosarcoma, consistent with the observations in TEMSC-treated mice. Finally, we isolated pure populations of EVs from serum and demonstrated that circulating levels of EV-associated TGF\u3b2 are increased in osteosarcoma patients.Conclusions: Collectively, our findings suggest that TEMSCs promote osteosarcoma progression and provide the basis for testing IL6- and TGF\u3b2-blocking agents as new therapeutic options for osteosarcoma patients. Clin Cancer Res; 23(14); 3721-33. \ua92017 AACR
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