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1.
Lancet ; 397(10271): 281-292, 2021 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-33485453

RESUMO

BACKGROUND: The Wee1 (WEE1hu) inhibitor adavosertib and gemcitabine have shown preclinical synergy and promising activity in early phase clinical trials. We aimed to determine the efficacy of this combination in patients with ovarian cancer. METHODS: In this double-blind, randomised, placebo-controlled, phase 2 trial, women with measurable recurrent platinum-resistant or platinum-refractory high-grade serous ovarian cancer were recruited from 11 academic centres in the USA and Canada. Women were eligible if they were aged 18 years or older, had an Eastern Cooperative Oncology Group performance status of 0-2, a life expectancy of more than 3 months, and normal organ and marrow function. Women with ovarian cancer of non-high-grade serous histology were eligible for enrolment in a non-randomised exploratory cohort. Eligible participants with high-grade serous ovarian cancer were randomly assigned (2:1), using block randomisation (block size of three and six) and no stratification, to receive intravenous gemcitabine (1000 mg/m2 on days 1, 8, and 15) with either oral adavosertib (175 mg) or identical placebo once daily on days 1, 2, 8, 9, 15, and 16, in 28-day cycles until disease progression or unacceptable toxicity. Patients and the team caring for each patient were masked to treatment assignment. The primary endpoint was progression-free survival. The safety and efficacy analysis population comprised all patients who received at least one dose of treatment. The trial is registered with ClinicalTrials.gov, NCT02151292, and is closed to accrual. FINDINGS: Between Sept 22, 2014, and May 30, 2018, 124 women were enrolled, of whom 99 had high-grade serous ovarian cancer and were randomly assigned to adavosertib plus gemcitabine (65 [66%]) or placebo plus gemcitabine (34 [34%]). 25 women with non-high-grade serous ovarian cancer were enrolled in the exploratory cohort. After randomisation, five patients with high-grade serous ovarian cancer were found to be ineligible (four in the experimental group and one in the control group) and did not receive treatment. Median age for all treated patients (n=119) was 62 years (IQR 54-67). Progression-free survival was longer with adavosertib plus gemcitabine (median 4·6 months [95% CI 3·6-6·4] with adavosertib plus gemcitabine vs 3·0 months [1·8-3·8] with placebo plus gemcitabine; hazard ratio 0·55 [95% CI 0·35-0·90]; log-rank p=0·015). The most frequent grade 3 or worse adverse events were haematological (neutropenia in 38 [62%] of 61 participants in the adavosertib plus gemcitabine group vs ten [30%] of 33 in the placebo plus gemcitabine group; thrombocytopenia in 19 [31%] of 61 in the adavosertib plus gemcitabine group vs two [6%] of 33 in the placebo plus gemcitabine group). There were no treatment-related deaths; two patients (one in each group in the high-grade serous ovarian cancer cohort) died while on study medication (from sepsis in the experimental group and from disease progression in the control group). INTERPRETATION: The observed clinical efficacy of a Wee1 inhibitor combined with gemcitabine supports ongoing assessment of DNA damage response drugs in high-grade serous ovarian cancer, a TP53-mutated tumour type with high replication stress. This therapeutic approach might be applicable to other tumour types with high replication stress; larger confirmatory studies are required. FUNDING: US National Cancer Institute Cancer Therapy Evaluation Program, Ontario Institute for Cancer Research, US Department of Defense, Princess Margaret Cancer Foundation, and AstraZeneca.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Desoxicitidina/análogos & derivados , Inibidores Enzimáticos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Pirazóis/uso terapêutico , Pirimidinonas/uso terapêutico , Canadá , Desoxicitidina/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Sobrevida , Estados Unidos , Gencitabina
2.
Br J Cancer ; 124(5): 951-962, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33339894

RESUMO

BACKGROUND: Schlafen 11 (SLFN11) has been linked with response to DNA-damaging agents (DDA) and PARP inhibitors. An in-depth understanding of several aspects of its role as a biomarker in cancer is missing, as is a comprehensive analysis of the clinical significance of SLFN11 as a predictive biomarker to DDA and/or DNA damage-response inhibitor (DDRi) therapies. METHODS: We used a multidisciplinary effort combining specific immunohistochemistry, pharmacology tests, anticancer combination therapies and mechanistic studies to assess SLFN11 as a potential biomarker for stratification of patients treated with several DDA and/or DDRi in the preclinical and clinical setting. RESULTS: SLFN11 protein associated with both preclinical and patient treatment response to DDA, but not to non-DDA or DDRi therapies, such as WEE1 inhibitor or olaparib in breast cancer. SLFN11-low/absent cancers were identified across different tumour types tested. Combinations of DDA with DDRi targeting the replication-stress response (ATR, CHK1 and WEE1) could re-sensitise SLFN11-absent/low cancer models to the DDA treatment and were effective in upper gastrointestinal and genitourinary malignancies. CONCLUSION: SLFN11 informs on the standard of care chemotherapy based on DDA and the effect of selected combinations with ATR, WEE1 or CHK1 inhibitor in a wide range of cancer types and models.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Dano ao DNA , Resistencia a Medicamentos Antineoplásicos , Proteínas Nucleares/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Padrão de Cuidado , Animais , Neoplasias da Mama/patologia , Feminino , Seguimentos , Humanos , Camundongos , Proteínas Nucleares/genética , Isoformas de Proteínas , Estudos Retrospectivos , Análise Serial de Tecidos , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Br J Cancer ; 125(12): 1666-1676, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34663950

RESUMO

BACKGROUND: The absence of the putative DNA/RNA helicase Schlafen11 (SLFN11) is thought to cause resistance to DNA-damaging agents (DDAs) and PARP inhibitors. METHODS: We developed and validated a clinically applicable SLFN11 immunohistochemistry assay and retrospectively correlated SLFN11 tumour levels to patient outcome to the standard of care therapies and olaparib maintenance. RESULTS: High SLFN11 associated with improved prognosis to the first-line treatment with DDAs platinum-plus-etoposide in SCLC patients, but was not strongly linked to paclitaxel-platinum response in ovarian cancer patients. Multivariate analysis of patients with relapsed platinum-sensitive ovarian cancer from the randomised, placebo-controlled Phase II olaparib maintenance Study19 showed SLFN11 tumour levels associated with sensitivity to olaparib. Study19 patients with high SLFN11 had a lower progression-free survival (PFS) hazard ratio compared to patients with low SLFN11, although both groups had the benefit of olaparib over placebo. Whilst caveated by small sample size, this trend was maintained for PFS, but not overall survival, when adjusting for BRCA status across the olaparib and placebo treatment groups, a key driver of PARP inhibitor sensitivity. CONCLUSION: We provide clinical evidence supporting the role of SLFN11 as a DDA therapy selection biomarker in SCLC and highlight the need for further clinical investigation into SLFN11 as a PARP inhibitor predictive biomarker.


Assuntos
Dano ao DNA/genética , Proteínas Nucleares/metabolismo , Animais , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Estudos Retrospectivos , Resultado do Tratamento
4.
Anal Chem ; 93(5): 2767-2775, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33474935

RESUMO

Clinical tissue specimens are often unscreened, and preparation of tissue sections for analysis by mass spectrometry imaging (MSI) can cause aerosolization of particles potentially carrying an infectious load. We here present a decontamination approach based on ultraviolet-C (UV-C) light to inactivate clinically relevant pathogens such as herpesviridae, papovaviridae human immunodeficiency virus, or SARS-CoV-2, which may be present in human tissue samples while preserving the biodistributions of analytes within the tissue. High doses of UV-C required for high-level disinfection were found to cause oxidation and photodegradation of endogenous species. Lower UV-C doses maintaining inactivation of clinically relevant pathogens to a level of increased operator safety were found to be less destructive to the tissue metabolome and xenobiotics. These doses caused less alterations of the tissue metabolome and allowed elucidation of the biodistribution of the endogenous metabolites. Additionally, we were able to determine the spatially integrated abundances of the ATR inhibitor ceralasertib from decontaminated human biopsies using desorption electrospray ionization-MSI (DESI-MSI).


Assuntos
Descontaminação/métodos , Raios Ultravioleta , Animais , Azetidinas/análise , Azetidinas/uso terapêutico , COVID-19/patologia , COVID-19/virologia , Neoplasias de Cabeça e Pescoço/química , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Metaboloma , Naftalenos/análise , Naftalenos/uso terapêutico , Fotólise/efeitos da radiação , Ratos , Ratos Wistar , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/efeitos da radiação , Espectrometria de Massas por Ionização por Electrospray/métodos , Terfenadina/química , Inativação de Vírus/efeitos da radiação
6.
Br J Cancer ; 119(10): 1233-1243, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30385821

RESUMO

BACKGROUND: AZD0156 and AZD6738 are potent and selective inhibitors of ataxia-telangiectasia-kinase (ATM) and ataxia-telangiectasia-mutated and Rad3-related (ATR), respectively, important sensors/signallers of DNA damage. METHODS: We used multiplexed targeted-mass-spectrometry to select pRAD50(Ser635) as a pharmacodynamic biomarker for AZD0156-mediated ATM inhibition from a panel of 45 peptides, then developed and tested a clinically applicable immunohistochemistry assay for pRAD50(Ser635) detection in FFPE tissue. RESULTS: We found moderate pRAD50 baseline levels across cancer indications. pRAD50 was detectable in 100% gastric cancers (n = 23), 99% colorectal cancers (n = 102), 95% triple-negative-breast cancers (TNBC) (n = 40) and 87.5% glioblastoma-multiformes (n = 16). We demonstrated AZD0156 target inhibition in TNBC patient-derived xenograft models; where AZD0156 monotherapy or post olaparib treatment, resulted in a 34-72% reduction in pRAD50. Similar inhibition of pRAD50 (68%) was observed following ATM inhibitor treatment post irinotecan in a colorectal cancer xenograft model. ATR inhibition, using AZD6738, increased pRAD50 in the ATM-proficient models whilst in ATM-deficient models the opposite was observed, suggesting pRAD50 pharmacodynamics post ATR inhibition may be ATM-dependent and could be useful to determine ATM functionality in patients treated with ATR inhibitors. CONCLUSION: Together these data support clinical utilisation of pRAD50 as a biomarker of AZD0156 and AZD6738 pharmacology to elucidate clinical pharmacokinetic/pharmacodynamic relationships, thereby informing recommended Phase 2 dose/schedule.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Espectrometria de Massas/métodos , Animais , Antineoplásicos/farmacologia , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Biomarcadores/metabolismo , Linhagem Celular , Dano ao DNA , Humanos , Imuno-Histoquímica , Indóis , Irinotecano/farmacologia , Camundongos , Camundongos Nus , Morfolinas , Ftalazinas/farmacologia , Piperazinas/farmacologia , Piridinas/farmacologia , Piridinas/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Transdução de Sinais , Sulfonamidas , Sulfóxidos/farmacologia , Sulfóxidos/uso terapêutico , Neoplasias de Mama Triplo Negativas , Ensaios Antitumorais Modelo de Xenoenxerto
7.
J R Army Med Corps ; 163(5): 311-318, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28356493

RESUMO

INTRODUCTION: Women in the military are a minority group who, in addition to facing exposure to traumatic events due to the nature of the work, face additional stressors while deployed. It is argued that these exposures and experiences place individuals at a significantly higher risk of finding it difficult adjusting post deployment. This paper focuses on the psychological health and well-being of female veterans post-deployment. METHODS: A systematic review of the literature related to female veterans' experiences upon returning home from deployment was conducted. RESULTS: Eight in-depth qualitative studies met the inclusion criteria for the study and were analysed using thematic analysis. Five key themes were identified in the papers: (1) bringing the war home, (2) post-deployment adjustment, (3) loss, (4) failed belongingness and (5) post-traumatic growth. CONCLUSIONS: These studies provide a useful insight into the different psychological health and well-being experiences that female veterans encounter. Additionally, the associated effects upon the individual and their families and communities are considered.


Assuntos
Saúde Mental/estatística & dados numéricos , Veteranos/psicologia , Veteranos/estatística & dados numéricos , Adulto , Feminino , Humanos , Pesquisa Qualitativa , Adulto Jovem
8.
Otolaryngol Head Neck Surg ; 171(2): 609-616, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38529665

RESUMO

OBJECTIVE: The number of tracheostomies performed annually in resource-rich countries is estimated at 250,000. While an essential procedure, approximately 20% to 30% of patients will experience at least 1 tracheostomy-related adverse event. Within tracheostomy care and across wider health care environments, quality improvement (QI) programs have been shown to reduce patient harm and improve outcomes. Herein we report on a 5-year long, tracheostomy QI initiative aimed at improving patient experience and reducing the frequency and severity of adverse events. METHODS: A 5-year (ongoing) QI initiative led by the Cardiff and Vale University Health Board tracheostomy team, within a tertiary, 1000-bedded hospital in South Wales, United Kingdom. The QI initiative has focused on 3 main themes: (1) Education and training; (2) Clinical oversight and decision making; and (3) improved data collection. Data were collected from existing tracheostomy databases. RESULTS: Over the past 5 years, we have observed a sustained reduction in both the frequency and severity of adverse events, with less than 1 patient per 100 experiencing a moderate or severe adverse event. This has resulted in improvements in patient experience and a cost reduction of £GBP364,726 per annum. DISCUSSION: Our 5-year ongoing tracheostomy QI initiative has resulted in improved outcomes with increased achievement of tracheostomy weaning markers and sustained reductions in both the frequency and severity of adverse events. IMPLICATIONS FOR PRACTICE: A continuous focus on QI is associated with improved patient and service outcomes. These improvements can be spread and scaled to benefit more patients and organizations.


Assuntos
Melhoria de Qualidade , Traqueostomia , Traqueostomia/efeitos adversos , Humanos , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , País de Gales
9.
J Clin Invest ; 134(2)2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-37934611

RESUMO

BACKGROUNDPhase 1 study of ATRinhibition alone or with radiation therapy (PATRIOT) was a first-in-human phase I study of the oral ATR (ataxia telangiectasia and Rad3-related) inhibitor ceralasertib (AZD6738) in advanced solid tumors.METHODSThe primary objective was safety. Secondary objectives included assessment of antitumor responses and pharmacokinetic (PK) and pharmacodynamic (PD) studies. Sixty-seven patients received 20-240 mg ceralasertib BD continuously or intermittently (14 of a 28-day cycle).RESULTSIntermittent dosing was better tolerated than continuous, which was associated with dose-limiting hematological toxicity. The recommended phase 2 dose of ceralasertib was 160 mg twice daily for 2 weeks in a 4-weekly cycle. Modulation of target and increased DNA damage were identified in tumor and surrogate PD. There were 5 (8%) confirmed partial responses (PRs) (40-240 mg BD), 34 (52%) stable disease (SD), including 1 unconfirmed PR, and 27 (41%) progressive disease. Durable responses were seen in tumors with loss of AT-rich interactive domain-containing protein 1A (ARID1A) and DNA damage-response defects. Treatment-modulated tumor and systemic immune markers and responding tumors were more immune inflamed than nonresponding.CONCLUSIONCeralasertib monotherapy was tolerated at 160 mg BD intermittently and associated with antitumor activity.TRIAL REGISTRATIONClinicaltrials.gov: NCT02223923, EudraCT: 2013-003994-84.FUNDINGCancer Research UK, AstraZeneca, UK Department of Health (National Institute for Health Research), Rosetrees Trust, Experimental Cancer Medicine Centre.


Assuntos
Morfolinas , Neoplasias , Pirimidinas , Sulfonamidas , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Indóis , Inflamação/tratamento farmacológico , Genômica , Proteínas Mutadas de Ataxia Telangiectasia/genética
10.
Nat Commun ; 15(1): 1700, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402224

RESUMO

The Ataxia telangiectasia and Rad3-related (ATR) inhibitor ceralasertib in combination with the PD-L1 antibody durvalumab demonstrated encouraging clinical benefit in melanoma and lung cancer patients who progressed on immunotherapy. Here we show that modelling of intermittent ceralasertib treatment in mouse tumor models reveals CD8+ T-cell dependent antitumor activity, which is separate from the effects on tumor cells. Ceralasertib suppresses proliferating CD8+ T-cells on treatment which is rapidly reversed off-treatment. Ceralasertib causes up-regulation of type I interferon (IFNI) pathway in cancer patients and in tumor-bearing mice. IFNI is experimentally found to be a major mediator of antitumor activity of ceralasertib in combination with PD-L1 antibody. Improvement of T-cell function after ceralasertib treatment is linked to changes in myeloid cells in the tumor microenvironment. IFNI also promotes anti-proliferative effects of ceralasertib on tumor cells. Here, we report that broad immunomodulatory changes following intermittent ATR inhibition underpins the clinical therapeutic benefit and indicates its wider impact on antitumor immunity.


Assuntos
Linfócitos T CD8-Positivos , Indóis , Morfolinas , Neoplasias , Pirimidinas , Sulfonamidas , Humanos , Animais , Camundongos , Antígeno B7-H1 , Microambiente Tumoral , Linhagem Celular Tumoral , Imunoterapia , Modelos Animais de Doenças , Proteínas Mutadas de Ataxia Telangiectasia
11.
Mol Ther ; 20(10): 1953-67, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22760542

RESUMO

Induced pluripotent stem cells (iPSCs) with potential for therapeutic applications can be derived from somatic cells via ectopic expression of a set of limited and defined transcription factors. However, due to risks of random integration of the reprogramming transgenes into the host genome, the low efficiency of the process, and the potential risk of virally induced tumorigenicity, alternative methods have been developed to generate pluripotent cells using nonintegrating systems, albeit with limited success. Here, we show that c-KIT+ human first-trimester amniotic fluid stem cells (AFSCs) can be fully reprogrammed to pluripotency without ectopic factors, by culture on Matrigel in human embryonic stem cell (hESC) medium supplemented with the histone deacetylase inhibitor (HDACi) valproic acid (VPA). The cells share 82% transcriptome identity with hESCs and are capable of forming embryoid bodies (EBs) in vitro and teratomas in vivo. After long-term expansion, they maintain genetic stability, protein level expression of key pluripotency factors, high cell-division kinetics, telomerase activity, repression of X-inactivation, and capacity to differentiate into lineages of the three germ layers, such as definitive endoderm, hepatocytes, bone, fat, cartilage, neurons, and oligodendrocytes. We conclude that AFSC can be utilized for cell banking of patient-specific pluripotent cells for potential applications in allogeneic cellular replacement therapies, pharmaceutical screening, and disease modeling.


Assuntos
Líquido Amniótico/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Ácido Valproico/farmacologia , Líquido Amniótico/citologia , Diferenciação Celular , Linhagem Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Genoma Humano , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Cariotipagem , Cinética , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Masculino , Proteína Homeobox Nanog , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Fenótipo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Análise de Sequência de DNA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma , Transgenes , Inativação do Cromossomo X/efeitos dos fármacos
12.
Dev World Bioeth ; 13(1): 21-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23521821

RESUMO

Identities ascribed to research staff in face-to-face encounters with participants have been raised as key ethical challenge in transnational health research. 'Misattributed' identities that do not just deviate from researchers' self-image, but obscure unequivocal aspects of researcher identity - e.g. that they are researchers - are a case of such ethical problem. Yet, the reasonable expectation of unconcealed identity can conflict with another ethical premise: confidentiality; this poses challenges to staff visiting participants at home. We explore these around a case study of 'follow-up' staff, observed during an ethnographic study of a Kenyan HIV 'trial community', which included participant observation, conversations, and interviews with staff (n = 79) and participants (n = 89). We found that because of the need to maintain confidentiality and because of some suspicions towards researchers, research staff drew upon alternative identities - presenting themselves to non-participants as relatives or friends, rather than as researchers. Several staff experienced this as necessary but uncomfortable. Simultaneously, staff and participants forged close relations in line with their fictional identities, which however also posed challenges because they entailed personal responsibilities that were difficult to live up to, due to limited resources, and the trial's limited duration. Similar challenges may arise in transnational HIV treatment programmes and should be explored further in that context.


Assuntos
Ensaios Clínicos como Assunto/ética , Pesquisa Participativa Baseada na Comunidade/ética , Confidencialidade/ética , Infecções por HIV , Pesquisadores/normas , Relações Pesquisador-Sujeito/ética , Responsabilidade Social , Confiança , Academias e Institutos , Adulto , Fármacos Anti-HIV/administração & dosagem , Ensaios Clínicos como Assunto/normas , Ensaios Clínicos como Assunto/tendências , Pesquisa Participativa Baseada na Comunidade/normas , Pesquisa Participativa Baseada na Comunidade/tendências , Feminino , Amigos , Infecções por HIV/tratamento farmacológico , Humanos , Cooperação Internacional , Satisfação no Emprego , Quênia , Adesão à Medicação , Pesquisadores/ética , Irmãos
13.
J Intensive Care Soc ; 24(1): 24-31, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36874286

RESUMO

Introduction: National guidelines suggest recommended staffing levels for therapies. The aim of this study was to capture information on existing staffing levels, roles and responsibilities and service structures. Methods: An observational study using online surveys distributed to 245 critical care units across the United Kingdom (UK). Surveys consisted of a generic and five profession specific surveys. Results: Eight hundred sixty-two responses were received from 197 critical care units across the UK. Of those that responded, over 96% of units had input from dietetics, physiotherapy and SLT. Whereas only 59.1% and 48.1% had an OT or psychology service respectively. Units with ring fenced services had improved therapist to patient ratios. Discussion: There is significant variation in access to therapists for patients admitted to critical care in the UK, with many services not having services for core therapies such as psychology and OT. Where services do exist, they fall below the recommended guidance.

14.
J Histochem Cytochem ; 71(5): 237-257, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37119278

RESUMO

Phosphorylated biomarkers are crucial for our understanding of drug mechanism of action and dose selection during clinical trials, particularly for drugs that target protein kinases, such as DNA-damage-response (DDR) inhibitors. However, tissue fixation conditions needed to preserve DDR-specific phospho-biomarkers have not been previously investigated. Using xenograft tissues and tightly controlled formalin fixation conditions, we assessed how preanalytical factors affect phosphorylated DDR biomarkers pRAD50(Ser635), ɣH2AX(Ser139), pKAP1(Ser824), and non-phosphorylated biomarkers cMYC and ATM. Cold ischemia times ranged from 15 min to 6 hr, and the fixation duration ranged from 24 hr to 4 weeks. Epitopes pRAD50 and pKAP1 appeared the most labile assessed with staining loss after just 15 min of cold ischemia time, while ATM was more robust showing consistent expression up to 1 hr of cold ischemia. Notably, ɣH2AX expression was lost with formalin fixation over 48 hr. The use of core needle biopsies where possible and novel fixation methods such as the 2-step temperature-controlled formalin approach may improve phosphorylated biomarker preservation; however, practical challenges may affect wider clinical application. The most essential tissue-processing step when downstream analysis includes DDR phosphorylated biomarkers is immediate tissue submersion in formalin, without delay, upon excision from the patient, followed by room temperature fixation for 24 hr.


Assuntos
Dano ao DNA , Formaldeído , Humanos , Epitopos , Biomarcadores , Fixação de Tecidos/métodos
15.
Cancers (Basel) ; 15(16)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37627223

RESUMO

Ataxia-telangiectasia mutated gene (ATM) is a key component of the DNA damage response (DDR) and double-strand break repair pathway. The functional loss of ATM (ATM deficiency) is hypothesised to enhance sensitivity to DDR inhibitors (DDRi). Whole-exome sequencing (WES), immunohistochemistry (IHC), and Western blotting (WB) were used to characterise the baseline ATM status across a panel of ATM mutated patient-derived xenograft (PDX) models from a range of tumour types. Antitumour efficacy was assessed with poly(ADP-ribose)polymerase (PARP, olaparib), ataxia- telangiectasia and rad3-related protein (ATR, AZD6738), and DNA-dependent protein kinase (DNA-PK, AZD7648) inhibitors as a monotherapy or in combination to associate responses with ATM status. Biallelic truncation/frameshift ATM mutations were linked to ATM protein loss while monoallelic or missense mutations, including the clinically relevant recurrent R3008H mutation, did not confer ATM protein loss by IHC. DDRi agents showed a mixed response across the PDX's but with a general trend toward greater activity, particularly in combination in models with biallelic ATM mutation and protein loss. A PDX with an ATM splice-site mutation, 2127T > C, with a high relative baseline ATM expression and KAP1 phosphorylation responded to all DDRi treatments. These data highlight the heterogeneity and complexity in describing targetable ATM-deficiencies and the fact that current patient selection biomarker methods remain imperfect; although, complete ATM loss was best able to enrich for DDRi sensitivity.

16.
Cancer Res ; 82(6): 1140-1152, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35078817

RESUMO

AZD6738 (ceralasertib) is a potent and selective orally bioavailable inhibitor of ataxia telangiectasia and Rad3-related (ATR) kinase. ATR is activated in response to stalled DNA replication forks to promote G2-M cell-cycle checkpoints and fork restart. Here, we found AZD6738 modulated CHK1 phosphorylation and induced ATM-dependent signaling (pRAD50) and the DNA damage marker γH2AX. AZD6738 inhibited break-induced replication and homologous recombination repair. In vitro sensitivity to AZD6738 was elevated in, but not exclusive to, cells with defects in the ATM pathway or that harbor putative drivers of replication stress such as CCNE1 amplification. This translated to in vivo antitumor activity, with tumor control requiring continuous dosing and free plasma exposures, which correlated with induction of pCHK1, pRAD50, and γH2AX. AZD6738 showed combinatorial efficacy with agents associated with replication fork stalling and collapse such as carboplatin and irinotecan and the PARP inhibitor olaparib. These combinations required optimization of dose and schedules in vivo and showed superior antitumor activity at lower doses compared with that required for monotherapy. Tumor regressions required at least 2 days of daily dosing of AZD6738 concurrent with carboplatin, while twice daily dosing was required following irinotecan. In a BRCA2-mutant patient-derived triple-negative breast cancer (TNBC) xenograft model, complete tumor regression was achieved with 3 to5 days of daily AZD6738 per week concurrent with olaparib. Increasing olaparib dosage or AZD6738 dosing to twice daily allowed complete tumor regression even in a BRCA wild-type TNBC xenograft model. These preclinical data provide rationale for clinical evaluation of AZD6738 as a monotherapy or combinatorial agent. SIGNIFICANCE: This detailed preclinical investigation, including pharmacokinetics/pharmacodynamics and dose-schedule optimizations, of AZD6738/ceralasertib alone and in combination with chemotherapy or PARP inhibitors can inform ongoing clinical efforts to treat cancer with ATR inhibitors.


Assuntos
Antineoplásicos , Neoplasias de Mama Triplo Negativas , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Carboplatina , Humanos , Indóis , Irinotecano , Morfolinas/farmacologia , Ftalazinas , Piperazinas , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/farmacologia , Sulfonamidas/farmacologia , Sulfóxidos/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética
17.
Clin Cancer Res ; 28(20): 4536-4550, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-35921524

RESUMO

PURPOSE: PARP inhibitors (PARPi) induce synthetic lethality in homologous recombination repair (HRR)-deficient tumors and are used to treat breast, ovarian, pancreatic, and prostate cancers. Multiple PARPi resistance mechanisms exist, most resulting in restoration of HRR and protection of stalled replication forks. ATR inhibition was highlighted as a unique approach to reverse both aspects of resistance. Recently, however, a PARPi/WEE1 inhibitor (WEE1i) combination demonstrated enhanced antitumor activity associated with the induction of replication stress, suggesting another approach to tackling PARPi resistance. EXPERIMENTAL DESIGN: We analyzed breast and ovarian patient-derived xenoimplant models resistant to PARPi to quantify WEE1i and ATR inhibitor (ATRi) responses as single agents and in combination with PARPi. Biomarker analysis was conducted at the genetic and protein level. Metabolite analysis by mass spectrometry and nucleoside rescue experiments ex vivo were also conducted in patient-derived models. RESULTS: Although WEE1i response was linked to markers of replication stress, including STK11/RB1 and phospho-RPA, ATRi response associated with ATM mutation. When combined with olaparib, WEE1i could be differentiated from the ATRi/olaparib combination, providing distinct therapeutic strategies to overcome PARPi resistance by targeting the replication stress response. Mechanistically, WEE1i sensitivity was associated with shortage of the dNTP pool and a concomitant increase in replication stress. CONCLUSIONS: Targeting the replication stress response is a valid therapeutic option to overcome PARPi resistance including tumors without an underlying HRR deficiency. These preclinical insights are now being tested in several clinical trials where the PARPi is administered with either the WEE1i or the ATRi.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Antineoplásicos/uso terapêutico , Proteínas Mutadas de Ataxia Telangiectasia , Proteína BRCA1/genética , Biomarcadores , Carcinoma Epitelial do Ovário/tratamento farmacológico , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Feminino , Humanos , Nucleosídeos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Ftalazinas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo
18.
Biomaterials ; 279: 121204, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34736146

RESUMO

The objective was to evaluate the performance of decellularised porcine superflexor tendon (pSFT) as an anterior cruciate ligament (ACL) reconstruction device. The ACL of adult sheep was reconstructed with decellularised pSFT or ovine allograft SFT and animals sacrificed at 4, 12 and 26 weeks (n = 4 per group) for biological evaluation and 26 weeks (n = 6) for biomechanical evaluation of the grafts. Both grafts showed good in vivo performance with no major differences at macroscopic evaluation post euthanasia. Histopathology revealed an inflammatory reaction to both grafts at 4 weeks, which reduced by 26 weeks. There was advanced cellular ingrowth from 12 weeks, ligamentisation of intra-articular grafts, ossification and formation of Sharpey's fibers at the graft/bone junctions. Immunohistochemistry showed that at 4 and 12 weeks, the host response was dominated by CD163+ M2 macrophages and a cell infiltrate comprising α-SMA + myofibroblasts, CD34+ and CD271+ progenitor cells. At 26 weeks the biomechanical properties of decellularised pSFT and oSFT grafts were comparable, with all grafts failing in the intra-articular region. This study provides new insight into constructive remodelling of tendons used for ACL replacement and evidence of integration and functional performance of a decellularised xenogeneic tendon with potential as an alternative for ACL reconstruction.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Animais , Ligamento Cruzado Anterior/cirurgia , Fenômenos Biomecânicos , Desempenho Físico Funcional , Ovinos , Suínos , Tendões , Transplante Homólogo
19.
BMJ Open Respir Res ; 8(1)2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34750167

RESUMO

INTRODUCTION: Therapists are increasing recognised as core members of the critical care multiprofessional team. Each therapy profession provides specialist assessments and interventions, but also work collaboratively across the rehabilitation pathway. Despite inclusion in several national guidance documents, there remains a lack of evidence regarding the perceived role of therapists working within critical care, the unique contributions of each profession and opinion on the day-to-day tasks and responsibilities of each therapy profession. METHOD: A descriptive qualitative methodology was used involving seven focus groups. Purposeful sampling was used to recruit therapists via professional specialist interest groups. All focus groups were uniprofessional and discussions based on a predesigned framework. Data were analysed thematically. RESULTS: Participants (n=65) from across the UK were recruited to seven focus groups with an average of 18.3 years postgraduate clinical experience of which 11.6 years was within critical care. Three core themes were generated from 875 codes and 237 potential subthemes. The final themes were (1) professional characteristics; (2) multidisciplinary team and (3) staffing. An additional theme of 'COVID-19 pandemic' was also identified. Findings were similar across all profession groups particularly regarding the need for holistic, patient-centred care. Expected variation was observed for professional characteristics especially regarding specific assessments and interventions. DISCUSSION: Therapy services are an essential component to the delivery of critical care especially regarding recovery and rehabilitation. Through three core themes, this qualitative study has provided new evidence of the perceptions and opinions of the role that therapists undertake within critical care.


Assuntos
COVID-19 , Pandemias , Cuidados Críticos , Grupos Focais , Humanos , SARS-CoV-2
20.
Trials ; 22(1): 193, 2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33685502

RESUMO

OBJECTIVES: The objective of this trial is to assess whether early antiviral therapy in outpatients with COVID-19 with either favipiravir plus lopinavir/ritonavir, lopinavir/ritonavir alone, or favipiravir alone, is associated with a decrease in viral load of SARS-CoV-2 compared with placebo. TRIAL DESIGN: FLARE is a phase IIA randomised, double-blind, 2x2 factorial placebo-controlled, interventional trial. PARTICIPANTS: This trial is being conducted in the United Kingdom, with Royal Free Hospital, London as the lead site. Participants are non-hospitalised adults with highly suspected COVID-19 within the first 5 days of symptom onset, or who have tested positive with SARS-CoV-2 causing COVID-19 within the first 7 days of symptom onset, or who are asymptomatic but tested positive for SARS-CoV-2 for the first time within the last 48 hours. Inclusion criteria are as follows: 1. Any adult with the following: Symptoms compatible with COVID-19 disease (Fever >37.8°C on at least one occasion AND either cough and/ or anosmia) within the first 5 days of symptom onset (date/time of enrolment must be within the first 5 days of symptom onset) OR ANY symptoms compatible with COVID-19 disease (may include, but are not limited to fever, cough, shortness of breath, malaise, myalgia, headache, coryza) and tested positive for SARS-CoV-2 within the first 7 days of symptom onset) (date/time of enrolment must be within the first 7 days of symptom onset) OR no symptoms but tested positive for SARS-CoV-2 within the last 48 hours (date/time of test must be within 48 hours of enrolment) 2. Male or female aged 18 years to 70 years old inclusive at screening 3. Willing and able to take daily saliva samples 4. Able to provide full informed consent and willing to comply with trial-related procedures Exclusion criteria are as follows: 1. Known hypersensitivity to any of the active ingredients or excipients in favipiravir and matched placebo, and in lopinavir/ritonavir and matched placebo (See Appendix 2) 2. Chronic liver disease at screening (known cirrhosis of any aetiology, chronic hepatitis (e.g. autoimmune, viral, steatohepatitis), cholangitis or any known elevation of liver aminotransferases with AST or ALT > 3 X ULN)* 3. Chronic kidney disease (stage 3 or beyond) at screening: eGFR < 60 ml/min/1.73m2 * 4. HIV infection, if untreated, detectable viral load or on protease inhibitor therapy 5. Any clinical condition which the investigator considers would make the participant unsuitable for the trial 6. Concomitant medications known to interact with favipiravir and matched placebo, and with lopinavir/ritonavir and matched placebo, and carry risk of toxicity for the participant 7. Current severe illness requiring hospitalisation 8. Pregnancy and/ or breastfeeding 9. Eligible female participants of childbearing potential and male participants with a partner of childbearing potential not willing to use highly effective contraceptive measures during the trial and within the time point specified following last trial treatment dose. 10. Participants enrolled in any other interventional drug or vaccine trial (co-enrolment in observational studies is acceptable) 11. Participants who have received the COVID-19 vaccine *Considering the importance of early treatment of COVID-19 to impact viral load, the absence of known chronic liver/ kidney disease will be confirmed verbally by the participant during pre-screening and Screening/Baseline visit. Safety blood samples will be collected at Screening/Baseline visit (Day 1) and test results will be examined as soon as they become available and within 24 hours. INTERVENTION AND COMPARATOR: Participants will be randomised 1:1:1:1 using a concealed online minimisation process into one of the following four arms: Arm 1: Favipiravir + Lopinavir/ritonavir Oral favipiravir at 1800mg twice daily on Day 1, followed by 400mg four (4) times daily from Day 2 to Day 7 PLUS lopinavir/ritonavir at 400mg/100mg twice daily on Day 1, followed by 200mg/50mg four (4) times daily from Day 2 to Day 7. Arm 2: Favipiravir + Lopinavir/ritonavir placebo Oral favipiravir at 1800mg twice daily on Day 1, followed by 400mg four (4) times daily from Day 2 to Day 7 PLUS lopinavir/ritonavir matched placebo at 400mg/100mg twice daily on Day 1, followed by 200mg/50mg four (4) times daily from Day 2 to Day 7. Arm 3: Favipiravir placebo + Lopinavir/ritonavir Oral favipiravir matched placebo at 1800mg twice daily on Day 1, followed by 400mg four (4) times daily from Day 2 to Day 7 PLUS lopinavir/ritonavir at 400mg/100mg twice daily on Day 1, followed by 200mg/50mg four (4) times daily from Day 2 to Day 7. Arm 4: Favipiravir placebo + Lopinavir/ritonavir placebo Oral favipiravir matched placebo at 1800mg twice daily on Day 1, followed by 400mg four (4) times daily from Day 2 to Day 7 PLUS lopinavir/ritonavir matched placebo at 400mg/100mg twice daily on Day 1, followed by 200mg/50mg four (4) times daily from Day 2 to Day 7. MAIN OUTCOMES: The primary outcome is upper respiratory tract viral load at Day 5. SECONDARY OUTCOMES: Percentage of participants with undetectable upper respiratory tract viral load after 5 days of therapy Proportion of participants with undetectable stool viral load after 7 days of therapy Rate of decrease in upper respiratory tract viral load during 7 days of therapy Duration of fever following commencement of trial medications Proportion of participants with hepatotoxicity after 7 days of therapy Proportion of participants with other medication-related toxicity after 7 days of therapy and 14 days post-randomisation Proportion of participants admitted to hospital with COVID-19 related illness Proportion of participants admitted to ICU with COVID-19 related illness Proportion of participants who have died with COVID-19 related illness Pharmacokinetic and pharmacodynamic analysis of favipiravir Exploratory: Proportion of participants with deleterious or resistance-conferring mutations in SARS-CoV-2 RANDOMISATION: Participants will be randomised 1:1:1:1 using a concealed online minimisation process, with the following factors: trial site, age (≤ 55 vs > 55 years old), gender, obesity (BMI <30 vs ≥30), symptomatic or asymptomatic, current smoking status (Yes = current smoker, No = ex-smoker, never smoker), ethnicity (Caucasian, other) and presence or absence of comorbidity (defined as diabetes, hypertension, ischaemic heart disease (including previous myocardial infarction), other heart disease (arrhythmia and valvular heart disease), asthma, COPD, other chronic respiratory disease). BLINDING (MASKING): Participants and investigators will both be blinded to treatment allocation (double-blind). NUMBERS TO BE RANDOMISED (SAMPLE SIZE): 240 participants, 60 in each arm. TRIAL STATUS: Protocol version 4.0 dated 7th January 2021. Date of first enrolment: October 2020. Recruitment is ongoing, with anticipated finish date of 31st March 2021. TRIAL REGISTRATION: The FLARE trial is registered with Clinicaltrials.gov, trial identifying number NCT04499677 , date of registration 4th August 2020. FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.


Assuntos
Amidas/uso terapêutico , Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Lopinavir/uso terapêutico , Pirazinas/uso terapêutico , Ritonavir/uso terapêutico , Carga Viral , Assistência Ambulatorial , Ensaios Clínicos Fase II como Assunto , Método Duplo-Cego , Combinação de Medicamentos , Quimioterapia Combinada , Intervenção Médica Precoce , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Reino Unido
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