Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 11 de 11
Filtrer
1.
F1000Res ; 12: 954, 2023.
Article de Anglais | MEDLINE | ID: mdl-37799492

RÉSUMÉ

With diminishing returns and high clinical failure rates from traditional preclinical and animal-based drug discovery strategies, more emphasis is being placed on alternative drug discovery platforms. Ex vivo approaches represent a departure from both more traditional preclinical animal-based models and clinical-based strategies and aim to address intra-tumoural and inter-patient variability at an earlier stage of drug discovery. Additionally, these approaches could also offer precise treatment stratification for patients within a week of tumour resection in order to direct tailored therapy. One tumour group that could significantly benefit from such ex vivo approaches are high-grade gliomas, which exhibit extensive heterogeneity, cellular plasticity and therapy-resistant glioma stem cell (GSC) niches. Historic use of murine-based preclinical models for these tumours has largely failed to generate new therapies, resulting in relatively stagnant and unacceptable survival rates of around 12-15 months post-diagnosis over the last 50 years. The near universal use of DNA damaging chemoradiotherapy after surgical resection within standard-of-care (SoC) therapy regimens provides an opportunity to improve current treatments if we can identify efficient drug combinations in preclinical models that better reflect the complex inter-/intra-tumour heterogeneity, GSC plasticity and inherent DNA damage resistance mechanisms. We have therefore developed and optimised a high-throughput ex vivo drug screening platform; GliExP, which maintains GSC populations using immediately dissociated fresh surgical tissue. As a proof-of-concept for GliExP, we have optimised SoC therapy responses and screened 30+ small molecule therapeutics and preclinical compounds against tumours from 18 different patients, including multi-region spatial heterogeneity sampling from several individual tumours. Our data therefore provides a strong basis to build upon GliExP to incorporate combination-based oncology therapeutics in tandem with SoC therapies as an important preclinical alternative to murine models (reduction and replacement) to triage experimental therapeutics for clinical translation and deliver rapid identification of effective treatment strategies for individual gliomas.


Sujet(s)
Tumeurs du cerveau , Glioblastome , Gliome , Humains , Animaux , Souris , Glioblastome/traitement médicamenteux , Évaluation préclinique de médicament , , Tumeurs du cerveau/traitement médicamenteux , Dépistage précoce du cancer , Cellules souches tumorales
2.
Expert Rev Mol Med ; 24: e39, 2022 10 03.
Article de Anglais | MEDLINE | ID: mdl-36184897

RÉSUMÉ

Despite advances in cancer genomics and the increased use of genomic medicine, metastatic cancer is still mostly an incurable and fatal disease. With diminishing returns from traditional drug discovery strategies, and high clinical failure rates, more emphasis is being placed on alternative drug discovery platforms, such as ex vivo approaches. Ex vivo approaches aim to embed biological relevance and inter-patient variability at an earlier stage of drug discovery, and to offer more precise treatment stratification for patients. However, these techniques also have a high potential to offer personalised therapies to patients, complementing and enhancing genomic medicine. Although an array of approaches are available to researchers, only a minority of techniques have made it through to direct patient treatment within robust clinical trials. Within this review, we discuss the current challenges to ex vivo approaches within clinical practice and summarise the contemporary literature which has directed patient treatment. Finally, we map out how ex vivo approaches could transition from a small-scale, predominantly research based technology to a robust and validated predictive tool. In future, these pre-clinical approaches may be integrated into clinical cancer pathways to assist in the personalisation of therapy choices and to hopefully improve patient experiences and outcomes.


Sujet(s)
Tumeurs , Humains , Tumeurs/thérapie , Tumeurs/traitement médicamenteux , Médecine de précision/méthodes , Oncologie médicale/méthodes , Génomique/méthodes
3.
BMJ Open ; 12(9): e063043, 2022 09 13.
Article de Anglais | MEDLINE | ID: mdl-36100297

RÉSUMÉ

INTRODUCTION: Glioblastoma is the most common malignant primary brain tumour with a median overall survival of 12-15 months (range 6-17 months), even with maximal treatment involving debulking neurosurgery and adjuvant concomitant chemoradiotherapy. The use of postoperative imaging to detect progression is of high importance to clinicians and patients, but currently, the optimal follow-up schedule is yet to be defined. It is also unclear how adhering to National Institute for Health and Care Excellence (NICE) guidelines-which are based on general consensus rather than evidence-affects patient outcomes such as progression-free and overall survival. The primary aim of this study is to assess MRI monitoring practice after surgery for glioblastoma, and to evaluate its association with patient outcomes. METHODS AND ANALYSIS: ImagiNg Timing aftER surgery for glioblastoma: an eVALuation of practice in Great Britain and Ireland is a retrospective multicentre study that will include 450 patients with an operated glioblastoma, treated with any adjuvant therapy regimen in the UK and Ireland. Adult patients ≥18 years diagnosed with glioblastoma and undergoing surgery between 1 August 2018 and 1 February 2019 will be included. Clinical and radiological scanning data will be collected until the date of death or date of last known follow-up. Anonymised data will be uploaded to an online Castor database. Adherence to NICE guidelines and the effect of being concordant with NICE guidelines will be identified using descriptive statistics and Kaplan-Meier survival analysis. ETHICS AND DISSEMINATION: Each participating centre is required to gain local institutional approval for data collection and sharing. Formal ethical approval is not required since this is a service evaluation. Results of the study will be reported through peer-reviewed presentations and articles, and will be disseminated to participating centres, patients and the public.


Sujet(s)
Tumeurs du cerveau , Glioblastome , Adulte , Tumeurs du cerveau/imagerie diagnostique , Tumeurs du cerveau/chirurgie , Glioblastome/imagerie diagnostique , Glioblastome/chirurgie , Humains , Irlande , Études multicentriques comme sujet , Études rétrospectives , Royaume-Uni
4.
Clin Endocrinol (Oxf) ; 96(4): 499-512, 2022 04.
Article de Anglais | MEDLINE | ID: mdl-34558728

RÉSUMÉ

OBJECTIVE: Phaeochromocytomas and paragangliomas (PPGL) are rare, but strongly heritable tumours. Variants in succinate dehydrogenase (SDH) subunits are identified in approximately 25% of cases. However, clinical and genetic information of patients with SDHC variants are underreported. DESIGN: This retrospective case series collated data from 18 UK Genetics and Endocrinology departments. PATIENTS: Both asymptomatic and disease-affected patients with confirmed SDHC germline variants are included. MEASUREMENTS: Clinical data including tumour type and location, surveillance outcomes and interventions, SDHC genetic variant assessment, interpretation, and tumour risk calculation. RESULTS: We report 91 SDHC cases, 46 probands and 45 non-probands. Fifty-one cases were disease-affected. Median age at genetic diagnosis was 43 years (range: 11-79). Twenty-four SDHC germline variants were identified including six novel variants. Head and neck paraganglioma (HNPGL, n = 30, 65.2%), extra-adrenal paraganglioma (EAPGL, n = 13, 28.2%) and phaeochromocytomas (PCC) (n = 3, 6.5%) were present. One case had multiple PPGLs. Malignant disease was reported in 19.6% (9/46). Eight cases had non-PPGL SDHC-associated tumours, six gastrointestinal stromal tumours (GIST) and two renal cell cancers (RCC). Cumulative tumour risk (95% CI) at age 60 years was 0.94 (CI: 0.79-0.99) in probands, and 0.16 (CI: 0-0.31) in non-probands, respectively. CONCLUSIONS: This study describes the largest cohort of 91 SDHC patients worldwide. We confirm disease-affected SDHC variant cases develop isolated HNPGL disease in nearly 2/3 of patients, EAPGL and PCC in 1/3, with an increased risk of GIST and RCC. One fifth developed malignant disease, requiring comprehensive lifelong tumour screening and surveillance.


Sujet(s)
Tumeurs de la surrénale , Néphrocarcinome , Tumeurs stromales gastro-intestinales , Tumeurs du rein , Paragangliome , Phéochromocytome , Tumeurs de la surrénale/génétique , Femelle , Mutation germinale/génétique , Humains , Mâle , Protéines membranaires/génétique , Adulte d'âge moyen , Paragangliome/génétique , Paragangliome/anatomopathologie , Phéochromocytome/génétique , Phéochromocytome/anatomopathologie , Études rétrospectives , Succinate Dehydrogenase/génétique , Succinate Dehydrogenase/métabolisme , Royaume-Uni
5.
Eur Geriatr Med ; 11(1): 63-70, 2020 02.
Article de Anglais | MEDLINE | ID: mdl-32297237

RÉSUMÉ

PURPOSE: Delirium is a common clinical syndrome associated with increased physical and psychological morbidity, mortality, inpatient stay and healthcare costs. There is growing interest in understanding the delirium experience and its psychological impact, including distress, for patients and their relatives, carers and healthcare providers. METHODS: This narrative review focuses on distress in delirium (DID) with an emphasis on its effect on older patients. It draws on qualitative and quantitative research to describe patient and environmental risk factors and variations in DID across a number of clinical settings, including medical and surgical inpatient wards and end of life care. The article provides an overview of the available distress assessment tools, both for clinical and research practice, and outlines their use in the context of delirium. This review also outlines established and emerging management strategies, focusing primarily on prevention and limitation of distress in delirium. RESULTS: Both significant illness and delirium cause distress. Patients who recall the episode of delirium describe common experiential features of delirium and distress. Relatives who witness delirium also experience distress, at levels suggested to be greater than that experienced by patients themselves. DID results in long-term psychological sequelae that can last months and years. Preventative actions, such pre-episode educational information for patients and their families in those at risk may reduce distress and psychological morbidity. CONCLUSIONS: Improving clinicians' understanding of the experience and long term psychological harm of delirium will enable the development of targeted support and information to patients at risk of delirium, and their families or carers.


Sujet(s)
Délire avec confusion , Aidants , Délire avec confusion/diagnostic , Personnel de santé , Humains , Patients hospitalisés , Rappel mnésique
6.
Nat Commun ; 10(1): 764, 2019 02 15.
Article de Anglais | MEDLINE | ID: mdl-30770825

RÉSUMÉ

The five-year survival rate of epithelial ovarian cancer (EOC) is approximately 35-40% despite maximal treatment efforts, highlighting a need for stratification biomarkers for personalized treatment. Here we extract 657 quantitative mathematical descriptors from the preoperative CT images of 364 EOC patients at their initial presentation. Using machine learning, we derive a non-invasive summary-statistic of the primary ovarian tumor based on 4 descriptors, which we name "Radiomic Prognostic Vector" (RPV). RPV reliably identifies the 5% of patients with median overall survival less than 2 years, significantly improves established prognostic methods, and is validated in two independent, multi-center cohorts. Furthermore, genetic, transcriptomic and proteomic analysis from two independent datasets elucidate that stromal phenotype and DNA damage response pathways are activated in RPV-stratified tumors. RPV and its associated analysis platform could be exploited to guide personalized therapy of EOC and is potentially transferrable to other cancer types.


Sujet(s)
Tumeurs de l'ovaire/génétique , Tumeurs de l'ovaire/métabolisme , Tomodensitométrie/méthodes , Altération de l'ADN/génétique , Femelle , Humains , Apprentissage machine , Protéomique
7.
Emerg Med J ; 33(5): 357-60, 2016 May.
Article de Anglais | MEDLINE | ID: mdl-26811420

RÉSUMÉ

The International Liaison Committee on Resuscitation recently released updated 2015 recommendations for resuscitation. The guidelines form the basis for all levels of resuscitation training, now from first aid to advanced life support (ALS), and for trainees of varying medical skills, from schoolchildren to medical students and consultants. We highlight major updates relating to intra-arrest and postarrest care, and the evidence for their recommendation. We also summarise areas of uncertainty in the evidence for ALS, and highlight current discussions that will likely inform the next round of recommendations.


Sujet(s)
Réanimation cardiopulmonaire/méthodes , Arrêt cardiaque/thérapie , Soins de maintien des fonctions vitales/méthodes , Guides de bonnes pratiques cliniques comme sujet , Réanimation cardiopulmonaire/normes , Services des urgences médicales/normes , Humains , Soins de maintien des fonctions vitales/normes
8.
Chem Sci ; 5(5): 1765-1771, 2014 May 01.
Article de Anglais | MEDLINE | ID: mdl-26682037

RÉSUMÉ

Carnitine is essential for fatty acid metabolism, but is associated with both health benefits and risks, especially heart diseases. We report the identification of potent, selective and cell active inhibitors of γ-butyrobetaine hydroxylase (BBOX), which catalyses the final step of carnitine biosynthesis in animals. A crystal structure of BBOX in complex with a lead inhibitor reveals that it binds in two modes, one of which adopts an unusual 'U-shape' conformation stabilised by inter- and intra-molecular π-stacking interactions. Conformational changes observed on binding of the inhibitor to BBOX likely reflect those occurring in catalysis; they also rationalise the inhibition of BBOX by high levels of its substrate γ-butyrobetaine (GBB), as observed both with isolated BBOX protein and in cellular studies.

9.
Epigenetics ; 9(12): 1596-603, 2014 Dec.
Article de Anglais | MEDLINE | ID: mdl-25625844

RÉSUMÉ

The JmjC-domain-containing 2-oxoglutarate-dependent oxygenases catalyze protein hydroxylation and N(ϵ)-methyllysine demethylation via hydroxylation. A subgroup of this family, the JmjC lysine demethylases (JmjC KDMs) are involved in histone modifications at multiple sites. There are conflicting reports as to the substrate selectivity of some JmjC oxygenases with respect to KDM activities. In this study, a panel of modified histone H3 peptides was tested for demethylation against 15 human JmjC-domain-containing proteins. The results largely confirmed known N(ϵ)-methyllysine substrates. However, the purified KDM4 catalytic domains showed greater substrate promiscuity than previously reported (i.e., KDM4A was observed to catalyze demethylation at H3K27 as well as H3K9/K36). Crystallographic analyses revealed that the N(ϵ)-methyllysine of an H3K27me3 peptide binds similarly to N(ϵ)-methyllysines of H3K9me3/H3K36me3 with KDM4A. A subgroup of JmjC proteins known to catalyze hydroxylation did not display demethylation activity. Overall, the results reveal that the catalytic domains of the KDM4 enzymes may be less selective than previously identified. They also draw a distinction between the N(ϵ)-methyllysine demethylation and hydroxylation activities within the JmjC subfamily. These results will be of use to those working on functional studies of the JmjC enzymes.


Sujet(s)
Jumonji Domain-Containing Histone Demethylases/métabolisme , Séquence d'acides aminés , Domaine catalytique , Protéines chromosomiques nonhistones/métabolisme , Dioxygenases , Protéines F-box/métabolisme , Histone Demethylases/métabolisme , Histone/métabolisme , Humains , Hydroxylation , Jumonji Domain-Containing Histone Demethylases/composition chimique , Lysine/analogues et dérivés , Lysine/métabolisme , Données de séquences moléculaires , Protéines nucléaires/métabolisme , Oxidoreductases, (N-demethylating)/métabolisme , Fragments peptidiques/métabolisme , Conformation des protéines , Spécificité du substrat
10.
J Thorac Oncol ; 8(6): 779-82, 2013 Jun.
Article de Anglais | MEDLINE | ID: mdl-23612464

RÉSUMÉ

INTRODUCTION: Intraoperative gold standards in the management of lung cancer include performing anatomical resection and mediastinal lymphadenectomy). Our aim was to measure improvement in quality of surgery by reauditing anatomical resection and lymph node excision in patients undergoing lung cancer surgery as per gold standards. METHODS: A complete audit cycle was performed-an initial retrospective analysis of 100 consecutive patients with primary lung cancer operated on by a single surgeon (July 2009-October 2010), followed by a prospective reaudit of 102 patients (November 2010-October 2011). Clinical and pathological data were collected from clinical notes, surgical database, and histopathology reports. Univariate and multivariate analyses were performed to identify further areas of potential improvement. RESULTS: The number of nonanatomical resections dropped from 12% to 6% (p = not significant). The rate of performing excision of at least 1, 2, and 3 mediastinal (N2) lymph node stations improved from 86% to 91%, 63% to 77%, and 40% to 63%, respectively (p = 0.003). On multivariate analysis, failure to perform anatomical resection was related to use of video assisted thoracic surgery (VATS) techniques, previous malignancy, and high-predicted surgical risk by European Society Objective Score .01. Less complete intraoperative lymph node excision was associated with cases performed by VATS and in octogenarians. CONCLUSIONS: There is continued adherence to the guidelines, when considering cases in terms of anatomical resections, and marked improvement in complying with the gold standards for lymph node excision. The use of the audit tool has contributed to improved quality of surgical care in patients operated for lung cancer.


Sujet(s)
Adénocarcinome/chirurgie , Carcinome à grandes cellules/chirurgie , Carcinome pulmonaire non à petites cellules/chirurgie , Carcinome épidermoïde/chirurgie , Tumeurs du poumon/chirurgie , Lymphadénectomie/normes , Audit médical , Pneumonectomie/normes , Adénocarcinome/anatomopathologie , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Carcinome à grandes cellules/anatomopathologie , Carcinome pulmonaire non à petites cellules/anatomopathologie , Carcinome épidermoïde/anatomopathologie , Femelle , Études de suivi , Humains , Tumeurs du poumon/anatomopathologie , Mâle , Médiastin/anatomopathologie , Médiastin/chirurgie , Adulte d'âge moyen , Stadification tumorale , Soins centrés sur le patient , Pronostic , Études prospectives , Études rétrospectives
11.
Nucleic Acids Res ; 40(Database issue): D783-9, 2012 Jan.
Article de Anglais | MEDLINE | ID: mdl-22058127

RÉSUMÉ

MACiE (which stands for Mechanism, Annotation and Classification in Enzymes) is a database of enzyme reaction mechanisms, and can be accessed from http://www.ebi.ac.uk/thornton-srv/databases/MACiE/. This article presents the release of Version 3 of MACiE, which not only extends the dataset to 335 entries, covering 182 of the EC sub-subclasses with a crystal structure available (~90%), but also incorporates greater chemical and structural detail. This version of MACiE represents a shift in emphasis for new entries, from non-homologous representatives covering EC reaction space to enzymes with mechanisms of interest to our users and collaborators with a view to exploring the chemical diversity of life. We present new tools for exploring the data in MACiE and comparing entries as well as new analyses of the data and new searches, many of which can now be accessed via dedicated Perl scripts.


Sujet(s)
Bases de données de protéines , Enzymes/composition chimique , Biocatalyse , Phénomènes biochimiques , Domaine catalytique , Coenzymes/composition chimique , Enzymes/classification , Internet , Annotation de séquence moléculaire
SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE