121 research outputs found

    Targeted radiotherapy of neuroblastoma: future directions

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    Inhibition of glycolysis and mitochondrial respiration promotes radiosensitisation of neuroblastoma and glioma cells

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    Background: Neuroblastoma accounts for 7% of paediatric malignancies but is responsible for 15% of all childhood cancer deaths. Despite rigorous treatment involving chemotherapy, surgery, radiotherapy and immunotherapy, the 5-year overall survival rate of high-risk disease remains < 40%, highlighting the need for improved therapy. Since neuroblastoma cells exhibit aberrant metabolism, we determined whether their sensitivity to radiotherapy could be enhanced by drugs affecting cancer cell metabolism. Methods: Using a panel of neuroblastoma and glioma cells, we determined the radiosensitising effects of inhibitors of glycolysis (2-DG) and mitochondrial function (metformin). Mechanisms underlying radiosensitisation were determined by metabolomic and bioenergetic profiling, flow cytometry and live cell imaging and by evaluating different treatment schedules. Results: The radiosensitising effects of 2-DG were greatly enhanced by combination with the antidiabetic biguanide, metformin. Metabolomic analysis and cellular bioenergetic profiling revealed this combination to elicit severe disruption of key glycolytic and mitochondrial metabolites, causing significant reductions in ATP generation and enhancing radiosensitivity. Combination treatment induced G2/M arrest that persisted for at least 24 h post-irradiation, promoting apoptotic cell death in a large proportion of cells. Conclusion: Our findings demonstrate that the radiosensitising effect of 2-DG was significantly enhanced by its combination with metformin. This clearly demonstrates that dual metabolic targeting has potential to improve clinical outcomes in children with high-risk neuroblastoma by overcoming radioresistance

    A European lens upon adult and lifelong learning in Asia

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    In this article, we seek to assess the extent to which adult and lifelong learning policies and practices in Asia have distinctiveness by comparison to those found in western societies, through an analysis of inter-governmental, national and regional policies in the field. We also inform our study through the analysis of the work of organisations with an international remit with a specific focus on Asia and Europe. In one case, the Asia–Europe Meeting Lifelong Learning (ASEM LLL) Hub has a specific function of bringing together researchers in Asia and Europe. In another, the PASCAL Observatory has had a particular focus on one aspect of lifelong learning, that of learning cities, with a concentration in its work on Asia and Europe. We focus on learning city development as a particular case of distinction in the field. We seek to identify the extent to which developments in the field in Asia have influenced and have been influenced by practices elsewhere in world, especially in Europe, and undertake our analysis using theories of societal learning/the learning society, learning communities and life-deep learning. We complement our analysis through assessment of material contained in three dominant journals in the field, the International Journal of Lifelong Education, the International Review of Education and Adult Education Quarterly, each edited in the west

    The alpha 7 nicotinic receptor agonist PHA-543613 hydrochloride inhibits <i>Porphyromonas gingivalis</i>-induced expression of interleukin-8 by oral keratinocytes

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    Objective: The alpha 7 nicotinic receptor (α7nAChR) is expressed by oral keratinocytes. α7nAChR activation mediates anti-inflammatory responses. The objective of this study was to determine if α7nAChR activation inhibited pathogen-induced interleukin-8 (IL-8) expression by oral keratinocytes.&lt;p&gt;&lt;/p&gt; Materials and methods: Periodontal tissue expression of α7nAChR was determined by real-time PCR. OKF6/TERT-2 oral keratinocytes were exposed to &lt;i&gt;Porphyromonas gingivalis&lt;/i&gt; in the presence and absence of a α7nAChR agonist (PHA-543613 hydrochloride) alone or after pre-exposure to a specific α7nAChR antagonist (α-bungarotoxin). Interleukin-8 (IL-8) expression was measured by ELISA and real-time PCR. Phosphorylation of the NF-ÎșB p65 subunit was determined using an NF-ÎșB p65 profiler assay and STAT-3 activation by STAT-3 in-cell ELISA. The release of ACh from oral keratinocytes in response to &lt;i&gt;P. gingivalis&lt;/i&gt; lipopolysaccharide was determined using a GeneBLAzer M3 CHO-K1-blacell reporter assay.&lt;p&gt;&lt;/p&gt; Results: Expression of α7nAChR mRNA was elevated in diseased periodontal tissue. PHA-543613 hydrochloride inhibited &lt;i&gt;P. Gingivalis&lt;/i&gt;-induced expression of IL-8 at the transcriptional level. This effect was abolished when cells were pre-exposed to a specific α7nAChR antagonist, α-bungarotoxin. PHA-543613 hydrochloride downregulated NF-ÎșB signalling through reduced phosphorylation of the NF-ÎșB p65-subunit. In addition, PHA-543613 hydrochloride promoted STAT-3 signalling by maintenance of phosphorylation. Furthermore, oral keratinocytes upregulated ACh release in response to &lt;i&gt;P. Gingivalis&lt;/i&gt; lipopolysaccharide.&lt;p&gt;&lt;/p&gt; Conclusion: These data suggest that α7nAChR plays a role in regulating the innate immune responses of oral keratinocytes.&lt;p&gt;&lt;/p&gt

    WNT signalling in prostate cancer

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    Genome sequencing and gene expression analyses of prostate tumours have highlighted the potential importance of genetic and epigenetic changes observed in WNT signalling pathway components in prostate tumours-particularly in the development of castration-resistant prostate cancer. WNT signalling is also important in the prostate tumour microenvironment, in which WNT proteins secreted by the tumour stroma promote resistance to therapy, and in prostate cancer stem or progenitor cells, in which WNT-ÎČ-catenin signals promote self-renewal or expansion. Preclinical studies have demonstrated the potential of inhibitors that target WNT receptor complexes at the cell membrane or that block the interaction of ÎČ-catenin with lymphoid enhancer-binding factor 1 and the androgen receptor, in preventing prostate cancer progression. Some WNT signalling inhibitors are in phase I trials, but they have yet to be tested in patients with prostate cancer

    Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

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    Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p&lt;0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p&lt;0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

    Chromosome conformation signatures define predictive markers of inadequate response to methotrexate in early rheumatoid arthritis

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    The authors would like to thank members of OBD Reference Facility Benjamin Foulkes, Chloe Bird, Emily Corfeld and Matthew Salter for expedient processing of clinical samples on the EpiSwitchℱ platform and Magdalena Jeznach and Willem Westra for help with preparation of the manuscript. The study employed samples from the SERA Biobank used with permission and approval of the SERA Approval Group. We gratefully acknowledge the invaluable contribution of the clinicians and operating team in SERA. We would also like to thank Prof. Raju Kucherlapati (Harvard Medical School), and Prof. Jane Mellor (Oxford Univ.), Prof. John O’Shea (National Institute of Health) and Prof. John Isaacs (New Castle Univ.) for their independent and critical review of our study. A list of Scottish Early Rheumatoid Arthritis (SERA) inception cohort investigators is provided in Additional fle 1: Additional Note. Funding This work was funded by Oxford BioDynamics.Peer reviewedPublisher PD

    An evaluation in vitro of PARP-1 inhibitors, rucaparib and olaparib, as radiosensitisers for the treatment of neuroblastoma

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    Background: The radiopharmaceutical 131I-meta-iodobenzylguanidine (131I-MIBG) is an effective treatment for neuroblastoma. However, maximal therapeutic benefit from 131I-MIBG is likely to be obtained by its combination with chemotherapy. We previously reported enhanced antitumour efficacy of 131I-MIBG by inhibition of the poly(ADP-ribose) polymerase-1 (PARP-1) DNA repair pathway using the phenanthridinone derivative PJ34. Recently developed alternative PARP-1 inhibitors have greater target specificity and are expected to be associated with reduced toxicity to normal tissue. Therefore, our purpose was to determine whether the more specific PARP-1 inhibitors rucaparib and olaparib enhanced the efficacy of X-radiation or 131I-MIBG. Methods: Radiosensitisation of SK-N-BE(2c) neuroblastoma cells or noradrenaline transporter gene-transfected glioma cells (UVW/NAT) was investigated using clonogenic assay. Propidium iodide staining and flow cytometry was used to analyse cell cycle progression. DNA damage was quantified by the phosphorylation of H2AX (γH2AX). Results: By combining PARP-1 inhibition with radiation treatment, it was possible to reduce the X-radiation dose or 131I-MIBG activity concentration required to achieve 50 % cell kill by approximately 50 %. Rucaparib and olaparib were equally effective inhibitors of PARP-1 activity. X-radiation-induced DNA damage was significantly increased 2 h after irradiation by combination with PARP-1 inhibitors (10-fold greater DNA damage compared to untreated controls; p &lt; 0.01). Moreover, combination treatment (i) prevented the restitution of DNA, exemplified by the persistence of 3-fold greater DNA damage after 24 h, compared to untreated controls (p &lt; 0.01) and (ii) induced greater G2/M arrest (p &lt; 0.05) than either single agent alone. Conclusion: Rucaparib and olaparib sensitise cancer cells to X-radiation or 131I-MIBG treatment. It is likely that the mechanism of radiosensitisation entails the accumulation of unrepaired radiation-induced DNA damage. Our findings suggest that the administration of PARP-1 inhibitors and 131I-MIBG to high risk neuroblastoma patients may be beneficial
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