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1.
Clin Oncol (R Coll Radiol) ; 36(5): 300-306, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38388251

RESUMO

AIMS: Squamous cell carcinoma oral cavity cancers (SCCOCCs) have a higher reported incidence in South Asian countries. We sought to compare presenting stage and outcome by ethnicity in patients with SCCOCC treated with radical radiotherapy in a single centre in the UK. MATERIALS AND METHODS: All patients with SCCOCC treated with radical radiotherapy at an oncology department in Leicester (UK) between 2011 and 2017 were identified. Baseline demographic, clinical data and 2-year treatment outcomes were reported. RESULTS: Of the 109 patients included, 40 were South Asian and 59 were non-South Asian. South Asians had significantly poorer 2-year disease-free survival compared with non-South Asians (54.6% versus 73%, P = 0.01). CONCLUSION: Our analysis suggests that South Asians with SCCOCC have poorer outcomes despite a younger age and similar disease characteristics. Environmental, social factors and differing biology of disease may be responsible and further research is required to inform targeted interventions.


Assuntos
Povo Asiático , Neoplasias Bucais , Humanos , Etnicidade , Resultado do Tratamento , Neoplasias Bucais/etnologia , Reino Unido
2.
Ann Oncol ; 35(1): 66-76, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37866811

RESUMO

BACKGROUND: Checkpoint inhibitor (CPI) therapy revolutionized treatment for advanced non-small-cell lung cancer (NSCLC); however, most patients progress due to primary or acquired resistance. Sitravatinib is a receptor tyrosine kinase inhibitor that can shift the immunosuppressive tumor microenvironment toward an immunostimulatory state. Combining sitravatinib with nivolumab (sitra + nivo) may potentially overcome initial CPI resistance. PATIENTS AND METHODS: In the phase III SAPPHIRE study, patients with advanced non-oncogenic driven, nonsquamous NSCLC who initially benefited from (≥4 months on CPI without progression) and subsequently experienced disease progression on or after CPI combined with or following platinum-based chemotherapy were randomized 1 : 1 to sitra (100 mg once daily administered orally) + nivo (240 mg every 2 weeks or 480 mg every 4 weeks administered intravenously) or docetaxel (75 mg/m2 every 3 weeks administered intravenously). The primary endpoint was overall survival (OS). The secondary endpoints included progression-free survival (PFS), objective response rate (ORR), clinical benefit rate (CBR), duration of response (DOR; all assessed by blinded independent central review), and safety. RESULTS: A total of 577 patients included randomized: sitra + nivo, n = 284; docetaxel, n = 293 (median follow-up, 17.1 months). Sitra + nivo did not significantly improve OS versus docetaxel [median, 12.2 versus 10.6 months; hazard ratio (HR) 0.86, 95% confidence interval (CI) 0.70-1.05; P = 0.144]. The median PFS was 4.4 versus 5.4 months, respectively (HR 1.08, 95% CI 0.89-1.32; P = 0.452). The ORR was 15.6% for sitra + nivo and 17.2% for docetaxel (P = 0.597); CBR was 75.5% and 64.5%, respectively (P = 0.004); median DOR was 7.4 versus 7.1 months, respectively (P = 0.924). Grade ≥3 treatment-related adverse events were observed in 53.0% versus 66.7% of patients receiving sitra + nivo versus docetaxel, respectively. CONCLUSIONS: Although median OS was numerically longer with sitra + nivo, the primary endpoint was not met in patients with previously treated advanced nonsquamous NSCLC. The safety profiles demonstrated were consistent with previous reports.


Assuntos
Anilidas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Piridinas , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Docetaxel/uso terapêutico , Nivolumabe/uso terapêutico , Neoplasias Pulmonares/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Microambiente Tumoral
3.
J Clin Med ; 12(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37834874

RESUMO

GD2, a disialoganglioside, is present on the surface of most neuroblastomas, as well as on some other cancers, such as melanoma and osteogenic sarcoma. The anti-GD2 antibody ch14.18 (dinutuximab) has an FDA-registered indication for use as maintenance therapy for high-risk neuroblastoma with cytokines and 13-cis-retinoic acid after myeloablative therapy. Recent studies using immunohistochemistry of tumor or tumor cells in marrow have shown that some neuroblastomas are negative for GD2. Dinutuximab and other anti-GD2 antibodies are increasingly used in combination with cytotoxic chemotherapy for treating relapsed neuroblastoma, so it is important to be able to identify patients with tumor cells with low GD2 expression, as such patients may experience toxicity but not benefit from the antibody therapy. As the most common clinical samples available for relapsed neuroblastoma are bone marrow aspirates, we developed a method to quantify dinutuximab binding density and the frequency of neuroblastoma cells positive for the antibody in bone marrow aspirates. Here, we describe a multi-color flow cytometry assay that employs non-GD2 antibodies to identify neuroblastoma cells in a mixed population (tumor, bone marrow, or blood) and an anti-GD2 antibody to quantify both the frequency and density of GD2 expression on neuroblastoma cells.

4.
Proc Nutr Soc ; : 1-9, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37759428

RESUMO

Consumption of snacks and ultra-processed foods (UPF) high in fat, salt and sugar (HFSS) is associated with rising rates of obesity and growing socioeconomic disparities in nutrition. While infancy, childhood and adolescence are critical periods for development of dietary preferences, there remains a dearth of research exploring factors that underpin snacking behaviour over this time. This review aims to address this gap by drawing from qualitative lived experience research, with 122 families of different socioeconomic position (SEP), to explore how the (i) home food environment, (ii) food environment and (iii) social value and meanings of food shape parental provision of snacks. This review shows that snacking holds important meanings in everyday family life, with infants integrated into existing snacking practices from an early age. Price promotions, low-cost and long shelf-lives all make UPF and HFSS snacks an appealing option for many low-SEP parents; while children's requests and preferences for HFSS snacks present a challenge across SEP. However, higher-SEP parents can ensure fresh fruits are always available as an alternative snack, while fruit is described as a financially risky expenditure for low-SEP families. The present findings also indicate that retailers and producers are increasingly promoting 'healthier' snacks through product packaging and marketing, such as 'meets one of your five a day', despite these products displaying similar nutritional profiles to traditional UPF and HFSS snacks. We outline a series of policy recommendations, including extending Healthy Start Vouchers and the Fruit and Vegetable Scheme in schools and action to address misleading product marketing and packaging.

5.
J Dairy Sci ; 106(10): 6880-6893, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37210373

RESUMO

This study investigated the effect of feeding seaweed (Ascophyllum nodosum) to dairy cows on milk mineral concentrations, feed-to-milk mineral transfer efficiencies, and hematological parameters. Lactating Holstein cows (n = 46) were allocated to 1 of 2 diets (n = 23 each): (1) control (CON; without seaweed) and (2) seaweed (SWD; replacing 330 g/d of dried corn meal in CON with 330 g/d dried A. nodosum). All cows were fed the CON diet for 4 wk before the experiment (adaptation period), and animals were then fed the experimental diets for 9 wk. Samples included sequential 3-wk composite feed samples, a composite milk sample on the last day of each week, and a blood sample at the end of the study. Data were statistically analyzed using a linear mixed effects model with diet, week, and their interaction as fixed factors; cow (nested within diet) as a random factor; and data collected on the last day of the adaptation period as covariates. Feeding SWD increased milk concentrations of Mg (+6.6 mg/kg), P (+56 mg/kg), and I (+1,720 µg/kg). It also reduced transfer efficiency of Ca, Mg, P, K, Mn, and Zn, and increased transfer efficiency of Mo. Feeding SWD marginally reduced milk protein concentrations, whereas there was no effect of SWD feeding on cows' hematological parameters. Feeding A. nodosum increased milk I concentrations, which can be beneficial when feed I concentration is limited or in demographics or populations with increased risk of I deficiency (e.g., female adolescents, pregnant women, nursing mothers). However, care should also be taken when feeding SWD to dairy cows because, in the present study, milk I concentrations were particularly high and could result in I intakes that pose a health risk for children consuming milk.


Assuntos
Ascophyllum , Alga Marinha , Criança , Bovinos , Feminino , Gravidez , Animais , Humanos , Adolescente , Lactação , Ração Animal/análise , Dieta/veterinária , Minerais/farmacologia , Verduras , Suplementos Nutricionais
6.
Cancer Chemother Pharmacol ; 92(2): 97-105, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37199745

RESUMO

PURPOSE: Fenretinide (4-HPR) is a synthetic retinoid that induces cytotoxicity through dihydroceramide production. Safingol, a stereochemical-variant dihydroceramide precursor, exhibits synergistic effects when administered with fenretinide in preclinical studies. We conducted a phase 1 dose-escalation clinical trial of this combination. METHODS: Fenretinide was administered as a 600 mg/m2 24-h infusion on Day 1 of a 21-day cycle followed by 900 mg/m2/day on Days 2 and 3. Safingol was concurrently administered as a 48-h infusion on Day 1 and 2 using 3 + 3 dose escalation. Primary endpoints were safety and maximum tolerated dose (MTD). Secondary endpoints included pharmacokinetics and efficacy. RESULTS: A total of 16 patients were enrolled (mean age 63 years, 50% female, median three prior lines of therapy), including 15 patients with refractory solid tumors and one with non-Hodgkin lymphoma. The median number of treatment cycles received was 2 (range 2-6). The most common adverse event (AE) was hypertriglyceridemia (88%; 38% ≥ Grade 3), attributed to the fenretinide intralipid infusion vehicle. Other treatment-related AEs occurring in ≥ 20% of patients included anemia, hypocalcemia, hypoalbuminemia, and hyponatremia. At safingol dose 420 mg/m2, one patient had a dose-limiting toxicity of grade 3 troponinemia and grade 4 myocarditis. Due to limited safingol supply, enrollment was halted at this dose level. Fenretinide and safingol pharmacokinetic profiles resembled those observed in monotherapy trials. Best radiographic response was stable disease (n = 2). CONCLUSION: Combination fenretinide plus safingol commonly causes hypertriglyceridemia and may be associated with cardiac events at higher safingol levels. Minimal activity in refractory solid tumors was observed. TRIAL REGISTRATION NUMBER: NCT01553071 (3.13.2012).


Assuntos
Antineoplásicos , Fenretinida , Hipertrigliceridemia , Neoplasias , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Neoplasias/tratamento farmacológico , Hipertrigliceridemia/induzido quimicamente , Hipertrigliceridemia/tratamento farmacológico
7.
Genes Chromosomes Cancer ; 62(5): 275-289, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36550020

RESUMO

Retinoblastomas form in response to biallelic RB1 mutations or MYCN amplification and progress to more aggressive and therapy-resistant phenotypes through accumulation of secondary genomic changes. Progression-related changes include recurrent somatic copy number alterations and typically non-recurrent nucleotide variants, including synonymous and non-coding variants, whose significance has been unclear. To determine if nucleotide variants recurrently affect specific biological processes, we identified altered genes and over-represented variant gene ontologies in 168 exome or whole-genome-sequenced retinoblastomas and 12 tumor-matched cell lines. In addition to RB1 mutations, MYCN amplification, and established retinoblastoma somatic copy number alterations, the analyses revealed enrichment of variant genes related to diverse biological processes including histone monoubiquitination, mRNA processing (P) body assembly, and mitotic sister chromatid segregation and cytokinesis. Importantly, non-coding and synonymous variants increased the enrichment significance of each over-represented biological process term. To assess the effects of such mutations, we examined the consequences of a 3' UTR variant of PCGF3 (a BCOR-binding component of Polycomb repressive complex I), dual 3' UTR variants of CDC14B (a regulator of sister chromatid segregation), and a synonymous variant of DYNC1H1 (a regulator of P-body assembly). One PCGF3 and one of two CDC14B 3' UTR variants impaired gene expression whereas a base-edited DYNC1H1 synonymous variant altered protease sensitivity and stability. Retinoblastoma cell lines retained only ~50% of variants detected in tumors and enriched for new variants affecting p53 signaling. These findings reveal potentially important differences in retinoblastoma cell lines and tumors and implicate synonymous and non-coding variants, along with non-synonymous variants, in retinoblastoma oncogenesis.


Assuntos
Neoplasias da Retina , Retinoblastoma , Humanos , Retinoblastoma/genética , Nucleotídeos , Proteína Proto-Oncogênica N-Myc/genética , Regiões 3' não Traduzidas , Mutação , Neoplasias da Retina/genética , Genes do Retinoblastoma , Fosfatases de Especificidade Dupla
8.
J Clin Densitom ; 25(4): 692-698, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36137876

RESUMO

INTRODUCTION: Dual energy X-ray absorptiometry (DXA) is widely used for the assessment of lean mass (LM), fat mass (FM) and bone mineral content (BMC). When observing standardised protocols, DXA has a high level of precision for the assessment of total body composition, including the head region. However, including the head region may have limited relevance in athletes and can be problematic when positioning taller athletes who exceed scan boundaries. This study investigated the precision of a new total-body-less-head (TBLH) DXA scan for three-compartment body composition measurement in athletes, with outcomes compared to the standard total-body DXA scan. METHODS: Precision errors were calculated from two consecutive scans with re-positioning (Lunar iDXA, GE Healthcare, Madison, WI), in male and female athletes from a range of sports. TBLH precision was determined from repeat scans in 95 athletes (male n = 55; female n = 40; age: 26.0 ± 8.5 y; body mass: 81.2 ± 20.5 kg; stature: 1.77 ± 0.11 m), and standard total-body scan precision was derived from a sub-sample of 58 athletes (male n = 19; female n = 39; age: 27.6 ± 9.9 y; body mass: 69.6 ± 14.8 kg; stature: 1.72 ± 0.94 m). Data from the sub-sample were also used to compare precision error and 3-compartment body composition outcomes between the standard total-body scan and the TBLH scan. RESULTS: TBLH precision errors [root mean squared-standard deviation, RMS-SD (coefficient of variation, %CV)] were bone mineral content (BMC): 15.6 g (0.5%), lean mass (LM): 254.3 g (0.4%) and fat mass (FM): 199.4 g (1.3%). These outcomes compared favourably to the precision errors derived from the standard total-body scan [BMC: 12.4 g (0.4%), LM: 202.2 g (0.4%), and FM: 160.8 g (1.1%)]. The TBLH scan resulted in lower BMC (-19.5%), LM (-6.6%), and FM (-4.5%) compared to the total-body scan (BMC: 2,308 vs. 2,865 g; LM: 46,954 vs. 50,276 g; FM: 15,183 vs. 15,888 g, all p<0.005). ConclusionThe TBLH scan demonstrates high in-vivo precision comparable to that of the standard total-body scan in a heterogeneous cohort of athletes. Given the impact of head exclusion on total body composition outcomes, TBLH scans should not be used interchangeably with the standard total-body scan.


Assuntos
Composição Corporal , Densidade Óssea , Masculino , Feminino , Humanos , Adolescente , Adulto Jovem , Adulto , Reprodutibilidade dos Testes , Absorciometria de Fóton/métodos , Atletas
9.
J Dairy Sci ; 105(9): 7462-7481, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35931475

RESUMO

Manure nitrogen (N) from cattle contributes to nitrous oxide and ammonia emissions and nitrate leaching. Measurement of manure N outputs on dairy farms is laborious, expensive, and impractical at large scales; therefore, models are needed to predict N excreted in urine and feces. Building robust prediction models requires extensive data from animals under different management systems worldwide. Thus, the study objectives were (1) to collate an international database of N excretion in feces and urine based on individual lactating dairy cow data from different continents; (2) to determine the suitability of key variables for predicting fecal, urinary, and total manure N excretion; and (3) to develop robust and reliable N excretion prediction models based on individual data from lactating dairy cows consuming various diets. A raw data set was created based on 5,483 individual cow observations, with 5,420 fecal N excretion and 3,621 urine N excretion measurements collected from 162 in vivo experiments conducted by 22 research institutes mostly located in Europe (n = 14) and North America (n = 5). A sequential approach was taken in developing models with increasing complexity by incrementally adding variables that had a significant individual effect on fecal, urinary, or total manure N excretion. Nitrogen excretion was predicted by fitting linear mixed models including experiment as a random effect. Simple models requiring dry matter intake (DMI) or N intake performed better for predicting fecal N excretion than simple models using diet nutrient composition or milk performance parameters. Simple models based on N intake performed better for urinary and total manure N excretion than those based on DMI, but simple models using milk urea N (MUN) and N intake performed even better for urinary N excretion. The full model predicting fecal N excretion had similar performance to simple models based on DMI but included several independent variables (DMI, diet crude protein content, diet neutral detergent fiber content, milk protein), depending on the location, and had root mean square prediction errors as a fraction of the observed mean values of 19.1% for intercontinental, 19.8% for European, and 17.7% for North American data sets. Complex total manure N excretion models based on N intake and MUN led to prediction errors of about 13.0% to 14.0%, which were comparable to models based on N intake alone. Intercepts and slopes of variables in optimal prediction equations developed on intercontinental, European, and North American bases differed from each other, and therefore region-specific models are preferred to predict N excretion. In conclusion, region-specific models that include information on DMI or N intake and MUN are required for good prediction of fecal, urinary, and total manure N excretion. In absence of intake data, region-specific complex equations using easily and routinely measured variables to predict fecal, urinary, or total manure N excretion may be used, but these equations have lower performance than equations based on intake.


Assuntos
Lactação , Nitrogênio , Animais , Bovinos , Dieta/veterinária , Fibras na Dieta/metabolismo , Feminino , Esterco , Leite/química , Nitrogênio/metabolismo , Ureia/metabolismo
10.
Cancer Res ; 82(18): 3345-3358, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-35947641

RESUMO

A subset of cancers across multiple histologies with predominantly poor outcomes use the alternative lengthening of telomeres (ALT) mechanism to maintain telomere length, which can be identified with robust biomarkers. ALT has been reported to be prevalent in high-risk neuroblastoma and certain sarcomas, and ALT cancers are a major clinical challenge that lack targeted therapeutic approaches. Here, we found ALT in a variety of pediatric and adult cancer histologies, including carcinomas. Patient-derived ALT cancer cell lines from neuroblastomas, sarcomas, and carcinomas were hypersensitive to the p53 reactivator eprenetapopt (APR-246) relative to telomerase-positive (TA+) models. Constitutive telomere damage signaling in ALT cells activated ataxia-telangiectasia mutated (ATM) kinase to phosphorylate p53, which resulted in selective ALT sensitivity to APR-246. Treatment with APR-246 combined with irinotecan achieved complete responses in mice xenografted with ALT neuroblastoma, rhabdomyosarcoma, and breast cancer and delayed tumor growth in ALT colon cancer xenografts, while the combination had limited efficacy in TA+ tumor models. A large number of adult and pediatric cancers present with the ALT phenotype, which confers a uniquely high sensitivity to reactivation of p53. These data support clinical evaluation of a combinatorial approach using APR-246 and irinotecan in ALT patients with cancer. SIGNIFICANCE: This work demonstrates that constitutive activation of ATM in chemotherapy-refractory ALT cancer cells renders them hypersensitive to reactivation of p53 function by APR-246, indicating a potential strategy to overcome therapeutic resistance.


Assuntos
Carcinoma , Neuroblastoma , Sarcoma , Telomerase , Animais , Humanos , Irinotecano , Camundongos , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Sarcoma/genética , Telomerase/genética , Telômero/genética , Telômero/metabolismo , Homeostase do Telômero/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
12.
J Dairy Sci ; 105(6): 5004-5023, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35450714

RESUMO

Estimating the efficiency of N utilization for milk production (MNE) of individual cows at a large scale is difficult, particularly because of the cost of measuring feed intake. Nitrogen isotopic discrimination (Δ15N) between the animal (milk, plasma, or tissues) and its diet has been proposed as a biomarker of the efficiency of N utilization in a range of production systems and ruminant species. The aim of this study was to assess the ability of Δ15N to predict the between-animal variability in MNE in dairy cows using an extensive database. For this, 20 independent experiments conducted as either changeover (n = 14) or continuous (n = 6) trials were available and comprised an initial data set of 1,300 observations. Between-animal variability was defined as the variation observed among cows sharing the same contemporary group (CG; individuals from the same experimental site, sampling period, and dietary treatment). Milk N efficiency was calculated as the ratio between mean milk N (grams of N in milk per day) and mean N intake (grams of N intake per day) obtained from each sampling period, which lasted 9.0 ± 9.9 d (mean ± SD). Samples of milk (n = 604) or plasma (n = 696) and feeds (74 dietary treatments) were analyzed for natural 15N abundance (δ15N), and then the N isotopic discrimination between the animal and the dietary treatment was calculated (Δ15n = δ15Nanimal - δ15Ndiet). Data were analyzed through mixed-effect regression models considering the experiment, sampling period, and dietary treatment as random effects. In addition, repeatability estimates were calculated for each experiment to test the hypothesis of improved predictions when MNE and Δ15N measurements errors were lower. The considerable protein mobilization in early lactation artificially increased both MNE and Δ15N, leading to a positive rather than negative relationship, and this limited the implementation of this biomarker in early lactating cows. When the experimental errors of Δ15N and MNE decreased in a particular experiment (i.e., higher repeatability values), we observed a greater ability of Δ15N to predict MNE at the individual level. The predominant negative and significant correlation between Δ15N and MNE in mid- and late lactation demonstrated that on average Δ15N reflects MNE variations both across dietary treatments and between animals. The root mean squared prediction error as a percentage of average observed value was 6.8%, indicating that the model only allowed differentiation between 2 cows in terms of MNE within a CG if they differed by at least 0.112 g/g of MNE (95% confidence level), and this could represent a limitation in predicting MNE at the individual level. However, the one-way ANOVA performed to test the ability of Δ15N to differentiate within-CG the top 25% from the lowest 25% individuals in terms of MNE was significant, indicating that it is possible to distinguish extreme animals in terms of MNE from their N isotopic signature, which could be useful to group animals for precision feeding.


Assuntos
Lactação , Leite , Ração Animal/análise , Animais , Biomarcadores , Bovinos , Dieta/veterinária , Feminino , Lactação/metabolismo , Leite/química , Nitrogênio/metabolismo , Isótopos de Nitrogênio/análise , Ruminantes/metabolismo
13.
EMBO J ; 41(8): e108272, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35211994

RESUMO

Most cancer deaths result from progression of therapy resistant disease, yet our understanding of this phenotype is limited. Cancer therapies generate stress signals that act upon mitochondria to initiate apoptosis. Mitochondria isolated from neuroblastoma cells were exposed to tBid or Bim, death effectors activated by therapeutic stress. Multidrug-resistant tumor cells obtained from children at relapse had markedly attenuated Bak and Bax oligomerization and cytochrome c release (surrogates for apoptotic commitment) in comparison with patient-matched tumor cells obtained at diagnosis. Electron microscopy identified reduced ER-mitochondria-associated membranes (MAMs; ER-mitochondria contacts, ERMCs) in therapy-resistant cells, and genetically or biochemically reducing MAMs in therapy-sensitive tumors phenocopied resistance. MAMs serve as platforms to transfer Ca2+ and bioactive lipids to mitochondria. Reduced Ca2+ transfer was found in some but not all resistant cells, and inhibiting transfer did not attenuate apoptotic signaling. In contrast, reduced ceramide synthesis and transfer was common to resistant cells and its inhibition induced stress resistance. We identify ER-mitochondria-associated membranes as physiologic regulators of apoptosis via ceramide transfer and uncover a previously unrecognized mechanism for cancer multidrug resistance.


Assuntos
Mitocôndrias , Neuroblastoma , Apoptose , Ceramidas , Resistência a Múltiplos Medicamentos , Humanos , Membranas Mitocondriais , Neuroblastoma/tratamento farmacológico
14.
Sci Transl Med ; 13(607)2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408079

RESUMO

Cancers overcome replicative immortality by activating either telomerase or an alternative lengthening of telomeres (ALT) mechanism. ALT occurs in ~25% of high-risk neuroblastomas, and progression in patients with ALT neuroblastoma during or after front-line therapy is frequent and often fatal. Temozolomide + irinotecan is commonly used as salvage therapy for neuroblastoma. Patient-derived cell lines and xenografts established from patients with relapsed ALT neuroblastoma demonstrated de novo resistance to temozolomide + irinotecan [SN-38 in vitro, P < 0.05; in vivo mouse event-free survival (EFS), P < 0.0001] vs. telomerase-positive neuroblastomas. We observed that ALT neuroblastoma cells manifested constitutive ataxia-telangiectasia mutated (ATM) activation due to spontaneous telomere dysfunction which was not observed in telomerase-positive neuroblastoma cells. We demonstrated that induction of telomere dysfunction resulted in ATM activation that, in turn, conferred resistance to temozolomide + SN-38 (4.2-fold change in IC50, P < 0.001). ATM knockdown (shRNA) or inhibition using a clinical-stage small-molecule inhibitor (AZD0156) reversed resistance to temozolomide + irinotecan in ALT neuroblastoma cell lines in vitro (P < 0.001) and in four ALT xenografts in vivo (EFS, P < 0.0001). AZD0156 showed modest to no enhancement of temozolomide + irinotecan activity in telomerase-positive neuroblastoma cell lines and xenografts. Ataxia telangiectasia and Rad3 related (ATR) inhibition using AZD6738 did not enhance temozolomide + SN-38 activity in ALT neuroblastoma cells. Thus, ALT neuroblastoma chemotherapy resistance occurs via ATM activation and is reversible with ATM inhibitor AZD0156. Combining AZD0156 with temozolomide + irinotecan warrants clinical testing for neuroblastoma.


Assuntos
Ataxia Telangiectasia , Neuroblastoma , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Resistencia a Medicamentos Antineoplásicos , Humanos , Camundongos , Recidiva Local de Neoplasia , Neuroblastoma/tratamento farmacológico , Piridinas , Quinolinas , Telômero , Homeostase do Telômero
16.
Appl Physiol Nutr Metab ; 46(11): 1430-1434, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34324824

RESUMO

Despite widespread use, community-based physical activity prescription is controversial. Data limitations have resulted in a lack of clarity about what works, under what circumstances, and for whom, reflected in conservative policy recommendations. In this commentary we challenge a predominantly negative discourse, using contemporary research to highlight promising findings and "lessons learnt" for design, delivery, and evaluation. In doing so, we argue for the importance of a more nuanced approach to future commissioning and evaluation. Novelty: Amalgamating learning from multiple research teams to create recommendations for advancing physical activity prescription.


Assuntos
Projetos de Pesquisa Epidemiológica , Exercício Físico , Promoção da Saúde , Humanos , Reino Unido
17.
Animal ; 15(7): 100248, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34098520

RESUMO

Minimising phosphorus (P) feeding to dairy cows can reduce feed costs and minimise water pollution without impairing animal performance. This study aimed to determine current P feeding practices and identify the barriers to and motivators for minimising P feeding on dairy farms, using Great Britain (GB) dairy farming as an example of diverse systems. Farmers (n = 139) and feed advisers (n = 31) were involved simultaneously in independent questionnaire surveys on P feeding in dairy farms. Data on the herd size, milk yield and concentrate fed were analysed using ANOVA to investigate the effect of farm classification, region, and feed professional advice. Chi-square tests were used to investigate associations between farm characteristics and implemented P feeding and management practices. Most farmers (72%) did not know the P concentration in their lactating cow's diet and did not commonly adopt precision P feeding practices, indicating that cows might have been offered dietary P in excess of recommended P requirement. Farmers' tendency to feed P in excess of recommendations increased with herd size, but so did their awareness of P pollution issues and likeliness of testing manure P. However, 68% of farmers did not analyse manure P, indicating that mineral P fertiliser application rates were not adjusted accordingly, highlighting the risk of P being applied beyond crops' requirement. Almost all farmers (96%) were willing to lower dietary P concentration but the uncertainty of P availability in feed ingredients (30%) and concerns over reduced cow fertility (22%) were primary barriers. The willingness to reduce dietary P concentrations was driven by the prospect of reducing environmental damage (28%) and feed costs (27%) and advice from their feed professionals (25%). Most farmers (70%) relied on a feed professional, and these farmers had a higher tendency to analyse their forage P. However, farmers of pasture-based systems relied less on feed professionals. Both farmers (73%) and feed advisers (68%) were unsatisfied with the amount of training on P management available. Therefore, the training on P management needs to be more available and the influence that feed professionals have over P feeding should be better utilised. Study findings demonstrate the importance of considering type of dairy farming systems when developing precision P feeding strategies and highlight the increasing importance of feed professionals in minimising P feeding.


Assuntos
Indústria de Laticínios , Lactação , Agricultura , Ração Animal/análise , Animais , Bovinos , Fazendas , Feminino , Leite/química , Fósforo/análise , Reino Unido
18.
Nutr Bull ; 46(2): 206-215, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33821147

RESUMO

Food systems are significant sources of global greenhouse gas emissions (GHGE). Since emission intensity varies greatly between different foods, changing food choices towards those with lower GHGE could make an important contribution to mitigating climate change. Public engagement events offer an opportunity to communicate these multifaceted issues and raise awareness about the climate change impact of food choices. An interdisciplinary team of researchers was preparing food and climate change educational activities for summer 2020. However, the COVID-19 pandemic and lockdown disrupted these plans. In this paper, we report on shifting these events online over the month of June 2020. We discuss what we did and the reception to our online programme. We then reflect on and highlight issues that arose. These relate to: (1) the power dynamics of children, diet and climate change; (2) mental health, diet and COVID-19; (3) engaging the wider science, agriculture and food communities; (4) the benefits of being unfunded and the homemade nature of this programme; (5) the food system, STEAM (science, technology, engineering, arts and mathematics) and diversity; and (6) how our work fits into our ongoing journey of food and climate change education.

19.
Transl Psychiatry ; 11(1): 147, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33654078

RESUMO

Late-life depression (LLD) is associated with an increased risk of developing dementia; however, it is not known whether individuals with a history of LLD exhibit a more rapid rate of cognitive decline. We aimed to determine whether those with LLD experienced faster cognitive decline compared with never-depressed control (NDC) participants from the community and whether stratification of LLD into early-onset depression (EOD) and late-onset depression (LOD) subtypes revealed differing rates and domain-specific expression of cognitive decline. We conducted a prospective, longitudinal study where 185 participants with LLD (remitted) and 114 NDC were followed for 5 years on average. EOD was defined as having first lifetime depressive episode at <60years and LOD at ≥60years. Every year, participants underwent comprehensive neuropsychological assessment. Composite scores for each cognitive domain were calculated through averaging standardized scores across tests. LLD compared to NDC demonstrated significant baseline impairment but did not decline more rapidly. EOD were significantly impaired in attention/processing speed and global cognitive function at baseline but did not experience more rapid decline as compared to NDC. Those with LOD compared to both NDC and EOD performed worse in all domains at baseline and experienced more rapid decline in verbal skills and delayed memory ability. Our findings suggest that baseline impairment may lower the threshold for those with LLD to develop dementia. EOD and LOD may represent distinct phenotypes of cognitive impairment with differing neural substrates. LOD may represent a distinct phenotype with a more rapid decline in verbal skills and delayed memory.


Assuntos
Disfunção Cognitiva , Demência , Idade de Início , Disfunção Cognitiva/epidemiologia , Demência/epidemiologia , Depressão , Humanos , Estudos Longitudinais , Testes Neuropsicológicos , Estudos Prospectivos
20.
Cancers (Basel) ; 13(4)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578855

RESUMO

Neuroblastoma is a paediatric malignancy of the developing sympathetic nervous system. About half of the patients have metastatic disease at the time of diagnosis and a survival rate of less than 50%. Our understanding of the cellular processes promoting neuroblastoma metastases will be facilitated by the development of appropriate experimental models. In this study, we aimed to explore the invasion of neuroblastoma cells and organoids from patient-derived xenografts (PDXs) grown embedded in 3D extracellular matrix (ECM) hydrogels by time-lapse microscopy and quantitative image analysis. We found that the ECM composition influenced the growth, viability and local invasion of organoids. The ECM compositions induced distinct cell behaviours, with Matrigel being the preferred substratum for local organoid invasion. Organoid invasion was cell line- and PDX-dependent. We identified six distinct phenotypes in PDX-derived organoids. In contrast, NB cell lines were more phenotypically restricted in their invasion strategies, as organoids isolated from cell line-derived xenografts displayed a broader range of phenotypes compared to clonal cell line clusters. The addition of FBS and bFGF induced more aggressive cell behaviour and a broader range of phenotypes. In contrast, the repression of the prognostic neuroblastoma marker, MYCN, resulted in less aggressive cell behaviour. The combination of PDX organoids, real-time imaging and the novel 3D culture assays developed herein will enable rapid progress in elucidating the molecular mechanisms that control neuroblastoma invasion.

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