60 research outputs found

    Histone deacetylase 6 controls Notch3 trafficking and degradation in T-cell acute lymphoblastic leukemia cells

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    Several studies have revealed that endosomal sorting controls the steady-state levels of Notch at the cell surface in normal cells and prevents its inappropriate activation in the absence of ligands. However, whether this highly dynamic physiologic process can be exploited to counteract dysregulated Notch signaling in cancer cells remains unknown. T-ALL is a malignancy characterized by aberrant Notch signaling, sustained by activating mutations in Notch1 as well as overexpression of Notch3, a Notch paralog physiologically subjected to lysosome-dependent degradation in human cancer cells. Here we show that treatment with the pan-HDAC inhibitor Trichostatin A (TSA) strongly decreases Notch3 full-length protein levels in T-ALL cell lines and primary human T-ALL cells xenografted in mice without substantially reducing NOTCH3 mRNA levels. Moreover, TSA markedly reduced the levels of Notch target genes, including pT alpha, CR2, and DTX-1, and induced apoptosis of T-ALL cells. We further observed that Notch3 was post-translationally regulated following TSA treatment, with reduced Notch3 surface levels and increased accumulation of Notch3 protein in the lysosomal compartment. Surface Notch3 levels were rescued by inhibition of dynein with ciliobrevin D. Pharmacologic studies with HDAC1, 6, and 8-specific inhibitors disclosed that these effects were largely due to inhibition of HDAC6 in TALL cells. HDAC6 silencing by specific shRNA was followed by reduced Notch3 expression and increased apoptosis of TALL cells. Finally, HDAC6 silencing impaired leukemia outgrowth in mice, associated with reduction of Notch3 full-length protein in vivo. These results connect HDAC6 activity to regulation of total and surface Notch3 levels and suggest HDAC6 as a potential novel therapeutic target to lower Notch signaling in T-ALL and other Notch3-addicted tumor

    Multi-layer resilience optimisation for next generation drone logistic networks

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    The paper will present a novel approach to the design optimisation of a resilient Drone Logistic Network (DLN) for the delivery of medical equipment. It is proposed a digital blueprint methodology that integrates Digital Twin (DT) models and optimisation tools, with the goal to optimise both the network topology and the delivery planningscheduling over the defined network. The DLN is a complex system being composed of a high number of different classes of drones and ground infrastructures which interconnections give rise to the whole network behaviour. Uncertainty, that comes in different forms, affects at different levels the subsystems and the whole network. The paper will present the generative network optimisation which is the approach used to define, by design, the network topology and configuration that are optimal for the defined Key Performance Indicators. It will then focus on the operational optimisation problem which, for a predefined DLN, aims at determining the optimal drone’s planning and scheduling considering also the uncertainty on the environment and the possible unexpected events

    Generative optimisation of resilient drone logistic networks

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    This paper presents a novel approach to the gener-ative design optimisation of a resilient Drone Logistic Network (DLN) for the delivery of medical equipment in Scotland. A DLN is a complex system composed of a high number of different classes of drones and ground infrastructures. The corresponding DLN model is composed of a number of interconnected digital twins of each one of these infrastructures and vehicles, forming a single digital twin of the whole logistic network. The paper proposes a multi-agent bio-inspired optimisation approach based on the analogy with the Physarum Policefalum slime mould that incrementally generates and optimise the DLN. A graph theory methodology is also employed to evaluate the network resilience where random failures, and their cascade effect, are simulated. The different conflicting objectives are aggregated into a single global performance index by using Pascoletti-Serafini scalarisation

    Inhibition of the Autophagy Pathway Synergistically Potentiates the Cytotoxic Activity of Givinostat (ITF2357) on Human Glioblastoma Cancer Stem Cells

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    Increasing evidence highlighted the role of cancer stem cells (CSCs) in the development of tumor resistance to therapy, particularly in glioblastoma (GBM). Therefore, the development of new therapies, specifically directed against GBM CSCs, constitutes an important research avenue. Considering the extended range of cancer-related pathways modulated by histone acetylation/deacetylation processes, we studied the anti-proliferative and pro-apoptotic efficacy of givinostat (GVS), a pan-histone deacetylase inhibitor, on cell cultures enriched in CSCs, isolated from nine human GBMs. We report that GVS induced a significant reduction of viability and self-renewal ability in all GBM CSC cultures; conversely, GVS exposure did not cause a significant cytotoxic activity toward differentiated GBM cells and normal mesenchymal human stem cells. Analyzing the cellular and molecular mechanisms involved, we demonstrated that GVS affected CSC viability through the activation of programmed cell death pathways. In particular, a marked stimulation of macroautophagy was observed after GVS treatment. To understand the functional link between GVS treatment and autophagy activation, different genetic and pharmacological interfering strategies were used. We show that the up-regulation of the autophagy process, obtained by deprivation of growth factors, induced a reduction of CSC sensitivity to GVS, while the pharmacological inhibition of the autophagy pathway and the silencing of the key autophagy gene ATG7, increased the cell death rate induced by GVS. Altogether these findings suggest that autophagy represents a pro-survival mechanism activated by GBM CSCs to counteract the efficacy of the anti-proliferative activity of GVS. In conclusion, we demonstrate that GVS is a novel pharmacological tool able to target GBM CSC viability and its efficacy can be enhanced by autophagy inhibitory strategies

    LHF Connect: a DIY telepresence robot against COVID-19

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    This contribution describes a case study of a “do-it-yourself” (DIY) opensource service and related product to help combating the COVID-19 emergency. It illustrates the birth of LHF Connect, a project designed to facilitate communication between patients isolated in COVID-19 hospitals’ ward and their relatives. LHF Connect is a teleoperated robot that can move in autonomy around the hospital. A User Centered Design approach, methods and specific tools helped in managing crucial steps of the design process such as i) the collection of needs coming from the context, stakeholders and end-users; ii) defining the service blueprint; iii) imagining finishing concepts; and iv) managing the communication activities. The initiative has been promoted by a multidisciplinary team of researchers (mainly roboticists with the help of specific competences coming from Design discipline)

    Expanding Thurston Maps

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    We study the dynamics of Thurston maps under iteration. These are branched covering maps ff of 2-spheres S2S^2 with a finite set post(f)\mathop{post}(f) of postcritical points. We also assume that the maps are expanding in a suitable sense. Every expanding Thurston map fS2S2f\: S^2 \to S^2 gives rise to a type of fractal geometry on the underlying sphere S2S^2. This geometry is represented by a class of \emph{visual metrics} ϱ\varrho that are associated with the map. Many dynamical properties of the map are encoded in the geometry of the corresponding {\em visual sphere}, meaning S2S^2 equipped with a visual metric ϱ\varrho. For example, we will see that an expanding Thurston map is topologically conjugate to a rational map if and only if (S2,ϱ)(S^2, \varrho) is quasisymmetrically equivalent to the Riemann sphere C^\widehat{\mathbf{C}}. We also obtain existence and uniqueness results for ff-invariant Jordan curves CS2\mathcal{C}\subset S^2 containing the set post(f)\mathop{post}(f). Furthermore, we obtain several characterizations of Latt\`{e}s maps

    Cytokines and inflammatory mediators: 25. Certolizumab Pegol has a Different Profile from the other Anti-TNFS, Including Golimumab, in a Variety of in Vitro Assays

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    Background: Activities of the anti-TNFs, certolizumab pegol (CZP), etanercept (ETA), infliximab (IFX) and adalimumab (ADA), have been compared in a range of in vitro assays. CZP is the only licensed PEGylated Fab' anti-TNF; ETA is a fusion protein with an IgG1 Fc, and IFX and ADA are both antibodies with an IgG1 Fc. Golimumab (GLM) is a monoclonal IgG1 TNF inhibitor recently approved for a number of indications; it is thus of interest to assess the in vitro activity of GLM. In vitro assays previously used were neutralisation of TNF in the L929 bioassay, inhibition of LPS-driven cytokine production by monocytes, induction of apoptosis in activated lymphocytes and monocytes, and induction of neutrophil necrosis. Methods: Neutralisation of human TNF was assessed in the L929 bioassay using a range of concentrations of the anti-TNFs and a fixed concentration of TNF (100 pg/mL). Activity of the anti-TNFs at inhibiting LPS-driven IL-1β secretion by monocytes was assessed by incubating peripheral blood monocytes with various concentrations of the anti-TNF for 1 hour (hr) and then washing the cells. LPS was added for 4 hrs, the supernatants collected and the IL-1β level measured by ELISA. To assess induction of apoptosis, peripheral blood lymphocytes were activated for 2 days with 2 μg/mL CD3/CD28 and monocytes with 300 U/mL IL-4 and GMCSF for 3 days. The effect of the anti-TNFs on apoptosis was assessed by Annexin V staining using flow cytometry 24 hrs later. The effect of the anti-TNFs on neutrophil necrosis was determined by measuring myeloperoxidase release after 12 hrs. An isotype-matched control was used in all assays except the L929 bioassay. Results: IC90 neutralisation activity of the anti-TNFs in the L929 bioassay was 0.3 ng/mL for ETA, 4 ng/mL for GLM, 15 ng/mL for ADA, and 20 ng/mL for IFX, compared with 2.5 ng/mL for CZP. CZP was the most potent inhibitor of LPS-driven IL-1β secretion (IC50 ∼0.1 ng/mL), followed by GLM (20 ng/mL) and IFX (50 ng/mL). GLM, ADA, IFX and ETA induced apoptosis of monocytes and lymphocytes to a similar degree reaching a level of 23% and ∼40% at 100 μg/mL, respectively. CZP caused no increase in apoptosis above the levels seen with the isotype-matched control. In the neutrophil necrosis assay, ADA,IFX and GLM caused ∼70% necrosis at 100 μg/mL, and ETA 48%. CZP did not increase the level of necrosis above the level of the control. Conclusions: Bioactivity of the IgG1 molecules GLM, IFX and ADA in neutralising human TNF was inferior to that of CZP and ETA. CZP, the only PEGylated anti-TNF, had a different profile to the other anti-TNFs as it was the most potent at inhibiting LPS-driven IL-1β production by monocytes, did not induce apoptosis of activated monocytes and lymphocytes, and did not cause neutrophil necrosis. The clinical relevance of these in vitro effects is unknown. Nevertheless, these assays show interesting in vitro differences between the anti-TNFs. Disclosure statement: G.F. and A.N. are employees of UC
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