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1.
Nat Microbiol ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622380

RESUMO

Children infected with SARS-CoV-2 rarely progress to respiratory failure. However, the risk of mortality in infected people over 85 years of age remains high. Here we investigate differences in the cellular landscape and function of paediatric (<12 years), adult (30-50 years) and older adult (>70 years) ex vivo cultured nasal epithelial cells in response to infection with SARS-CoV-2. We show that cell tropism of SARS-CoV-2, and expression of ACE2 and TMPRSS2 in nasal epithelial cell subtypes, differ between age groups. While ciliated cells are viral replication centres across all age groups, a distinct goblet inflammatory subtype emerges in infected paediatric cultures and shows high expression of interferon-stimulated genes and incomplete viral replication. In contrast, older adult cultures infected with SARS-CoV-2 show a proportional increase in basaloid-like cells, which facilitate viral spread and are associated with altered epithelial repair pathways. We confirm age-specific induction of these cell types by integrating data from in vivo COVID-19 studies and validate that our in vitro model recapitulates early epithelial responses to SARS-CoV-2 infection.

2.
Science ; 384(6694): eadf5489, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38662826

RESUMO

Tubulin, one of the most abundant cytoskeletal building blocks, has numerous isotypes in metazoans encoded by different conserved genes. Whether these distinct isotypes form cell type- and context-specific microtubule structures is poorly understood. Based on a cohort of 12 patients with primary ciliary dyskinesia as well as mouse mutants, we identified and characterized variants in the TUBB4B isotype that specifically perturbed centriole and cilium biogenesis. Distinct TUBB4B variants differentially affected microtubule dynamics and cilia formation in a dominant-negative manner. Structure-function studies revealed that different TUBB4B variants disrupted distinct tubulin interfaces, thereby enabling stratification of patients into three classes of ciliopathic diseases. These findings show that specific tubulin isotypes have distinct and nonredundant subcellular functions and establish a link between tubulinopathies and ciliopathies.


Assuntos
Axonema , Centríolos , Cílios , Microtúbulos , Tubulina (Proteína) , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Humanos , Animais , Microtúbulos/metabolismo , Camundongos , Cílios/metabolismo , Axonema/metabolismo , Centríolos/metabolismo , Ciliopatias/genética , Ciliopatias/metabolismo , Transtornos da Motilidade Ciliar/genética , Transtornos da Motilidade Ciliar/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Mutação
3.
Transplantation ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38499511

RESUMO

BACKGROUND: The outcomes after kidney transplantation (KT), including access, wait time, and other issues around the globe, have been studied. However, issues do vary from one country to another. METHODS: We obtained data from several countries from North America, South America, Europe, Asia, and Australia, including the number of patients awaiting KT from 2015, transplant rate per million population (pmp), proportion of living donor and deceased donor (LD/DD) KT, and posttransplant survival. We also sought opinions on key difficulties faced by each of these countries with respect to KT and long-term survival. RESULTS: Variation in access to KT across the globe was noted. Countries with the highest rates of KT pmp included the United States (79%) and Spain (71%). A higher proportion of LD transplants was noted in Japan (93%), India (85%), Singapore (63%), and South Korea (63%). A higher proportion of DD KTs was noted in Spain (90%), Brazil (90%), France (85%), Italy (85%), Finland (85%), Australia-New Zealand (80%), and the United States (77%). The 5-y graft survival for LD was highest in South Korea (95%), Singapore (94%), Italy (93%), Finland (93%), and Japan (93%), whereas for DD, it was South Korea (93%), Italy (88%), Japan (86%), and Singapore (86%). The common issues surrounding KTs are access and a limited number of LDs and DDs. Key issues identified for long-term survival were increasing age of donors and recipients, higher recipient comorbidity, and posttransplant events, such as alloimmune injury to the kidney, infection, cancer, and suboptimal adherence to therapy. CONCLUSIONS: A unified approach is necessary to improve issues surrounding KT as the demand continues to increase.

4.
Neuro Oncol ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38502052

RESUMO

BACKGROUND: Standard treatment for patients with newly diagnosed glioblastoma includes surgery, radiotherapy (RT) and temozolomide (TMZ) chemotherapy (TMZ/RT→TMZ). The proteasome has long been considered a promising therapeutic target because of its role as a central biological hub in tumor cells. Marizomib is a novel pan-proteasome inhibitor that crosses the blood brain barrier. METHODS: EORTC 1709/CCTG CE.8 was a multicenter, randomized, controlled, open label phase 3 superiority trial. Key eligibility criteria included newly diagnosed glioblastoma, age > 18 years and Karnofsky performance status > 70. Patients were randomized in a 1:1 ratio. The primary objective was to compare overall survival (OS) in patients receiving marizomib in addition to TMZ/RT→TMZ with patients receiving only standard treatment in the whole population, and in the subgroup of patients with MGMT promoter-unmethylated tumors. RESULTS: The trial was opened at 82 institutions in Europe, Canada and the US. A total of 749 patients (99.9% of planned 750) were randomized. OS was not different between the standard and the marizomib arm (median 17 vs 16.5 months; HR=1.04; p=0.64). PFS was not statistically different either (median 6.0 vs. 6.3 months; HR=0.97; p=0.67). In patients with MGMT promoter-unmethylated tumors, OS was also not different between standard therapy and marizomib (median 14.5 vs 15.1 months, HR=1.13; p=0.27). More CTCAE grade 3/4 treatment-emergent adverse events were observed in the marizomib arm than in the standard arm. CONCLUSIONS: Adding marizomib to standard temozolomide-based radiochemotherapy resulted in more toxicity, but did not improve OS or PFS in patients with newly diagnosed glioblastoma.

5.
Am J Transplant ; 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38360185

RESUMO

The time to arrest donors after circulatory death is unpredictable and can vary. This leads to variable periods of warm ischemic damage prior to pancreas transplantation. There is little evidence supporting procurement team stand-down times based on donor time to death (TTD). We examined what impact TTD had on pancreas graft outcomes following donors after circulatory death (DCD) simultaneous pancreas-kidney transplantation. Data were extracted from the UK transplant registry from 2014 to 2022. Predictors of graft loss were evaluated using a Cox proportional hazards model. Adjusted restricted cubic spline models were generated to further delineate the relationship between TTD and outcome. Three-hundred-and-seventy-five DCD simultaneous kidney-pancreas transplant recipients were included. Increasing TTD was not associated with graft survival (adjusted hazard ratio HR 0.98, 95% confidence interval 0.68-1.41, P = .901). Increasing asystolic time worsened graft survival (adjusted hazard ratio 2.51, 95% confidence interval 1.16-5.43, P = .020). Restricted cubic spline modeling revealed a nonlinear relationship between asystolic time and graft survival and no relationship between TTD and graft survival. We found no evidence that TTD impacts pancreas graft survival after DCD simultaneous pancreas-kidney transplantation; however, increasing asystolic time was a significant predictor of graft loss. Procurement teams should attempt to minimize asystolic time to optimize pancreas graft survival rather than focus on the duration of TTD.

6.
Arch Dis Child ; 109(4): 334-338, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38336457

RESUMO

INTRODUCTION: During the COVID-19 pandemic, evidence emerged that immunosuppressed children were less affected by COVID-19 infections compared with immunosuppressed adults. The aim of our study was to investigate how COVID-19 infections affected paediatric kidney transplant recipients (pKTR) in the UK. METHODS: Questionnaires regarding COVID-19 infection data and care of pKTR during the COVID-19 pandemic were sent to all 13 UK paediatric nephrology centres examining asymptomatic and symptomatic pKTR with positive COVID-19 PCR testing from 1 April 2020 to 1 December 2021. RESULTS: 63 pKTR who were 3.1 (range 0.1-15) years post-transplantation had COVID-19 infection with positive SARS-CoV-2 PCR RNA. Classical COVID-19 symptoms were present in half of the patients; with atypical presentations including diarrhoea (13%) and lethargy (13%) also noted, while a third of patients were asymptomatic. Eighteen patients (28%) were hospitalised including five asymptomatic patients admitted for other reasons. No patients needed ventilation or intensive care admission, and one patient received supplemental oxygen. There was evidence of acute kidney injury (AKI) in 71% of patients, but no patients needed kidney replacement therapy with haemofiltration or dialysis. CONCLUSION: We report 10.4% of the UK paediatric renal transplantation population had documented COVID-19 infections with positive SARS-CoV-2 PCR RNA with 28% of those affected requiring hospitalisation. The increased incidence of AKI, particularly after the first wave of the COVID-19 pandemic, was possibly due to increased testing. There was low morbidity and mortality compared with the adult population.


Assuntos
Injúria Renal Aguda , COVID-19 , Transplante de Rim , Criança , Humanos , COVID-19/epidemiologia , Estudos Transversais , Transplante de Rim/efeitos adversos , Pandemias , Estudos Retrospectivos , RNA , SARS-CoV-2
7.
Ambio ; 53(5): 730-745, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38360970

RESUMO

There exists an extensive, diverse, and robust evidence base to support complex decisions that address the planetary biodiversity crisis. However, it is generally not sought or used by environmental decision-makers, who instead draw on intuition, experience, or opinion to inform important decisions. Thus, there is a need to examine evidence exchange processes in wildlife management to understand the multiple inputs to decisions. Here, we adopt a novel approach, fuzzy cognitive mapping (FCM), to examine perceptions of individuals from Indigenous and Western governments on the reliability of evidence which may influence freshwater fisheries management decisions in British Columbia, Canada. We facilitated four FCM workshops participants representing Indigenous or Western regulatory/governance groups of fisheries managers. Our results show that flows of evidence to decision-makers occur within a relatively closed governance network, constrained to the few well-connected decision-making organizations (i.e., wildlife management agencies) and their close partners. This implies that increased collaboration (i.e., knowledge co-production) and engagement (i.e., knowledge brokerage) with wildlife managers and decision-makers are needed to produce actionable evidence and increase evidence exchange.


Assuntos
Animais Selvagens , Tomada de Decisões , Animais , Humanos , Reprodutibilidade dos Testes , Biodiversidade , Água Doce , Conservação dos Recursos Naturais
8.
Clin Cancer Res ; 30(6): 1121-1130, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38170586

RESUMO

PURPOSE: Sidedness is prognostic and predictive of anti-EGFR efficacy in metastatic colorectal cancer (mCRC). Transverse colon has been historically excluded from several analyses of sidedness and the optimal division between left- and right-sided colorectal cancer is unclear. We investigated transverse colon primary tumor location as a biomarker in mCRC. EXPERIMENTAL DESIGN: Pooled analysis of CCTG/AGITG CO.17 and CO.20 trials of cetuximab in chemotherapy-refractory mCRC. Outcomes of patients with RAS/BRAF wild-type (WT) mCRC from CO.17 and KRAS WT mCRC from CO.20 were analyzed according to location. RESULTS: A total of 553 patients were analyzed, 32 (5.8%) with cancers from the transverse, 101 (18.3%) from right, and 420 from (75.9%) left colon. Transverse mCRC failed to reach significant benefit from cetuximab versus best supportive care (BSC) for overall survival [OS; median, 5.9 vs. 2.1 months; HR, 0.63; 95% confidence interval (CI), 0.28-1.42; P=0.26] and progression-free survival (PFS; median, 1.8 vs. 1.3 months; HR, 0.57; 95% CI, 0.26-1.28; P=0.16). Analyzing exclusively patients randomized to cetuximab, right-sided and transverse had comparable outcomes for OS (median, 5.6 vs. 5.9 months; HR, 0.82; 95% CI, 0.50-1.34; P=0.43) and PFS (median, 1.9 vs. 1.8 months; HR, 0.78; 95% CI, 0.49-1.26; P=0.31). Patients with left-sided mCRC had superior outcomes with cetuximab compared with transverse for OS (median, 9.7 vs. 5.9 months; HR, 0.42; 95% CI, 0.27-0.67; P=0.0002) and PFS (median, 3.8 vs. 1.8 months; HR, 0,49; 95% CI, 0.31-0.76; P=0.001). Location was not prognostic in patients treated with BSC alone. CONCLUSIONS: Transverse mCRC has comparable prognostic and predictive features with right-sided mCRC.


Assuntos
Colo Transverso , Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , Cetuximab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Colo Transverso/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Neoplasias Retais/tratamento farmacológico , Biomarcadores , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
9.
Appl Microbiol Biotechnol ; 108(1): 174, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38270650

RESUMO

DNA methylases of the restriction-modifications (R-M) systems are promising enzymes for the development of novel molecular and synthetic biology tools. Their use in vitro enables the deployment of independent and controlled catalytic reactions. This work aimed to produce recombinant DNA methylases belonging to the R-M systems, capable of in vitro inhibition of the type IIS restriction enzymes BsaI, BpiI, or LguI. Non-switchable methylases are those whose recognition sequences fully overlap the recognition sequences of their associated endonuclease. In switch methylases, the methylase and endonuclease recognition sequences only partially overlap, allowing sequence engineering to alter methylation without altering restriction. In this work, ten methylases from type I and II R-M systems were selected for cloning and expression in E. coli strains tolerant to methylation. Isopropyl ß-D-1-thiogalactopyranoside (IPTG) concentrations and post-induction temperatures were tested to optimize the soluble methylases expression, which was achieved with 0.5 mM IPTG at 20 °C. The C-terminal His6-Tag versions showed better expression than the N-terminal tagged versions. DNA methylation was analyzed using purified methylases and custom test plasmids which, after the methylation reactions, were digested using the corresponding associated type IIS endonuclease. The non-switchable methylases M2.Eco31I, M2.BsaI, M2.HpyAII, and M1.MboII along with the switch methylases M.Osp807II and M2.NmeMC58II showed the best activity for site-selective inhibition of type IIS restriction enzyme activity. This work demonstrates that our recombinant methylases were able to block the activity of type IIS endonucleases in vitro, allowing them to be developed as valuable tools in synthetic biology and DNA assembly techniques. KEY POINTS: • Non-switchable methylases always inhibit the relevant type IIS endonuclease activity • Switch methylases inhibit the relevant type IIS endonuclease activity depending on the sequence engineering of their recognition site • Recombinant non-switchable and switch methylases were active in vitro and can be deployed as tools in synthetic biology and DNA assembly.


Assuntos
Metilação de DNA , Escherichia coli , Escherichia coli/genética , Isopropiltiogalactosídeo , Metiltransferases , Enzimas de Restrição-Modificação do DNA , Endonucleases
10.
Transplant Rev (Orlando) ; 38(1): 100801, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37840003

RESUMO

The British Transplantation Society (BTS) 'Guideline on transplantation from deceased donors after circulatory death' has recently been updated and this manuscript summarises the relevant recommendations in abdominal organ transplantation from Donation after Circulatory Death (DCD) donors, encompassing the chapters on liver, kidney, pancreas and islet cell transplantation.


Assuntos
Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Humanos , Doadores de Tecidos , Pâncreas , Rim , Sobrevivência de Enxerto
11.
Clin Transplant ; 38(1): e15166, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37848266

RESUMO

BACKGROUND: Appendicitis in pancreatic transplant recipients can be challenging to diagnose and manage. Incidental appendicectomy (IA) during pancreas transplantation obviates the risk of appendicitis but potentially at the cost of increased operating time or early post-operative complications. This study reviewed the value of IA at a single center. METHODS: This was a retrospective study of patients who underwent a pancreas transplant in our unit from January 1st, 2012 to December 31st, 2020, with end of follow-up on May 21st, 2023; recipients were grouped by whether or not an IA was performed during pancreas transplantation. Donor, recipient, operative, and graft outcomes were compared between the two groups. Post-transplant complications related to appendiceal pathology (or IA) were recorded and classified. RESULTS: Two hundred forty-three patients underwent a pancreas transplant; 227 (93%) patients had an appendix in situ at transplantation, and of these 53 (23%) underwent an IA and 174 (77%) did not. There were no statistically significant differences in operative time (p = .06) or hospital stay (p = .50) between the two groups. In the IA cohort, there were no Clavien-Dindo Grade III-V complications relating to the appendicectomy. In those that did not undergo an IA, two patients (1%) subsequently required appendicectomy due to appendicitis. Comparison of pancreatic graft survival showed no statistically significant difference between the groups (p = .44). CONCLUSIONS: This study suggests that IA is effective at reducing risks of post-transplant appendiceal complications without significantly prolonging inpatient stay or impairing graft survival. These data support the consideration of undertaking an IA for all patients undergoing a pancreas transplant.


Assuntos
Apendicite , Transplante de Pâncreas , Humanos , Apendicite/diagnóstico , Apendicite/cirurgia , Apendicite/complicações , Transplante de Pâncreas/efeitos adversos , Estudos Retrospectivos , Apendicectomia/efeitos adversos , Tempo de Internação , Sobrevivência de Enxerto
12.
Transplant Rev (Orlando) ; 38(1): 100803, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37919138

RESUMO

The British Transplantation Society (BTS) 'Guideline on transplantation from deceased donors after circulatory death' has recently been updated and this manuscript summarises the relevant recommendations from chapters specifically related to law, ethics, donor consent and informing the recipient.


Assuntos
Obtenção de Tecidos e Órgãos , Humanos , Doadores de Tecidos , Consentimento Livre e Esclarecido
13.
JAMA Netw Open ; 6(12): e2346094, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38051531

RESUMO

Importance: Immune checkpoint inhibitors (ICIs) have limited activity in microsatellite-stable (MSS) or mismatch repair-proficient (pMMR) colorectal cancer. Recent findings suggest the efficacy of ICIs may be modulated by the presence of liver metastases (LM). Objective: To investigate the association between the presence of LM and ICI activity in advanced MSS colorectal cancer. Design, Setting, and Participants: In this secondary analysis of the Canadian Cancer Trials Group CO26 (CCTG CO.26) randomized clinical trial, patients with treatment-refractory colorectal cancer were randomized in a 2:1 fashion to durvalumab plus tremelimumab or best supportive care alone between August 10, 2016, and June 15, 2017. The primary end point was overall survival (OS) with 80% power and 2-sided α = .10. The median follow-up was 15.2 (0.2-22.0) months. In this post hoc analysis performed from February 11 to 14, 2022, subgroups were defined based on the presence or absence of LM and study treatments. Intervention: Durvalumab plus tremelimumab or best supportive care. Main Outcomes and Measures: Hazard ratios (HRs) and 90% CIs were calculated based on a stratified Cox proportional hazards regression model. Plasma tumor mutation burden at study entry was determined using a circulating tumor DNA assay. The primary end point of the study was OS, defined as the time from randomization to death due to any cause; secondary end points included progression-free survival (PFS) and disease control rate (DCR). Results: Of 180 patients enrolled (median age, 65 [IQR, 36-87] years; 121 [67.2%] men; 19 [10.6%] Asian, 151 [83.9%] White, and 10 [5.6%] other race or ethnicity), LM were present in 127 (70.6%). For patients with LM, there was a higher proportion of male patients (94 of 127 [74.0%] vs 27 of 53 [50.9%]; P = .005), and the time from initial cancer diagnosis to study entry was shorter (median, 40 [range, 8-153] vs 56 [range, 14-181] months; P = .001). Plasma tumor mutation burden was significantly higher in patients with LM. Patients without LM had significantly improved PFS with durvalumab plus tremelimumab (HR, 0.54 [90% CI, 0.35-0.96]; P = .08; P = .02 for interaction). Disease control rate was 49% (90% CI, 36%-62%) in patients without LM treated with durvalumab plus tremelimumab, compared with 14% (90% CI, 6%-38%) in those with LM (odds ratio, 5.70 [90% CI, 1.46-22.25]; P = .03). On multivariable analysis, patients without LM had significantly improved OS and PFS compared with patients with LM. Conclusions and Relevance: In this secondary analysis of the CCTG CO.26 study, the presence of LM was associated with worse outcomes for patients with advanced colorectal cancer. Patients without LM had improved PFS and higher DCR with durvalumab plus tremelimumab. Liver metastases may be associated with poor outcomes of ICI treatment in advanced colorectal cancer and should be considered in the design and interpretation of future clinical studies evaluating this therapy.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Hepáticas , Neoplasias Retais , Idoso , Feminino , Humanos , Masculino , Biomarcadores Tumorais/análise , Canadá , Neoplasias do Colo/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Intervalo Livre de Progressão , Neoplasias Retais/tratamento farmacológico , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais
15.
Transpl Int ; 36: 11428, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37779511

RESUMO

Whilst renal transplantation is the optimal treatment for many patients with end-stage kidney disease, the latest international guidelines are unable to make recommendations for the management of patients with end-stage kidney stage kidney disease and Class III Obesity (BMI ≥40 kg/m2). Data on all adult patients receiving a kidney-only-transplant in the UK between 2015-2021 were analysed from a prospectively collected database and interrogated across a range of parameters. We then analysed in detail the outcomes of patients transplanted at the highest-volume unit. There were 22,845 renal transplants in the study time-period; just 44 (0.2%) were performed in recipients with a BMI ≥40 kg/m2. Most transplant centres did not transplant any patients in this category. In the centre with the highest volume, there were 21 transplants (9 living donor) performed in 20 individuals (13 male, median age 46 years). One-year patient and death-censored graft survival was 95% and 85%. Successful transplantation is possible in patients with BMI ≥40 kg/m2 but carries additional risk. Obesity should not be the sole factor considered when deciding on transplant suitability. Restricting transplantation to a small number of high-volume centres in each country should be considered to optimize outcomes.


Assuntos
Falência Renal Crônica , Transplante de Rim , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Transplante de Rim/efeitos adversos , Obesidade/complicações , Obesidade/cirurgia , Sobrevivência de Enxerto , Doadores Vivos , Resultado do Tratamento , Estudos Retrospectivos
16.
Transplant Rev (Orlando) ; 37(4): 100794, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37660415

RESUMO

Maximising organ utilisation from donation after circulatory death (DCD) donors could help meet some of the shortfall in organ supply, but it represents a major challenge, particularly as organ donors and transplant recipients become older and more medically complex over time. Success is dependent upon establishing common practices and accepted protocols that allow the safe sharing of DCD organs and maximise the use of the DCD donor pool. The British Transplantation Society 'Guideline on transplantation from deceased donors after circulatory death' has recently been updated. This manuscript summarises the relevant recommendations from chapters specifically related to transplantation of cardiothoracic organs.


Assuntos
Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Humanos , Doadores de Tecidos , Transplantados , Sobrevivência de Enxerto
17.
Clin Colorectal Cancer ; 22(4): 457-463, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37704538

RESUMO

BACKGROUND: Cetuximab is a standard of care therapy for patients with RAS wild-type (WT) advanced colorectal cancer. Limited data suggest a wide variation in cetuximab plasma concentrations after standard dosing regimens. We correlated cetuximab plasma concentrations with survival and toxicity. METHODS: The CO. 20 study randomized patients with RAS WT advanced colorectal cancer in a 1:1 ratio to cetuximab 400 mg/m2 intravenously followed by weekly maintenance of 250 mg/m2, plus brivanib 800 mg orally daily or placebo. Blood samples obtained at week 5 precetuximab treatment were analyzed by ELISA. Patients were grouped into tertiles based on plasma cetuximab concentrations. Cetuximab concentration tertiles were correlated with survival outcomes and toxicity. Patient demographic and biochemical parameters were evaluated as co-variables. RESULTS: Week 5 plasma cetuximab concentrations were available for 591 patients (78.8%). The median overall survival (OS) was 11.4 months and 7.8 months for patients in the highest (T3) and lowest tertiles (T1) respectively. On multivariable analysis, plasma cetuximab concentration was associated with OS (HR 0.66, 95% confidence interval [CI]: 0.53-0.83, P < .001, T3 vs. T1), and a trend towards progression-free survival (HR 0.82, 95% CI: 0.66-1.02, P = .07, T3 vs. T1). There was no association between cetuximab concentration and skin toxicity or diarrhea. CONCLUSION: The standard cetuximab dosing regimen may not be optimal for all patients. Further pharmacokinetic studies are needed to optimize cetuximab dosing given the potential improvement in OS.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Cetuximab , Proteínas Proto-Oncogênicas p21(ras)/genética , Intervalo Livre de Doença , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
18.
Transplant Rev (Orlando) ; 37(4): 100791, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37598591

RESUMO

Recipient outcomes after transplantation with organs from donation after circulatory death (DCD) donors can compare favourably and even match recipient outcomes after transplantation with organs from donation after brain death donors. Success is dependent upon establishing common practices and accepted protocols that allow the safe sharing of DCD organs and maximise the use of the DCD donor pool. The British Transplantation Society 'Guideline on transplantation from deceased donors after circulatory death' has recently been updated. This manuscript summarises the relevant recommendations from chapters specifically related to organ donation.


Assuntos
Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Humanos , Doadores de Tecidos , Morte Encefálica , Sobrevivência de Enxerto
19.
Int J Radiat Oncol Biol Phys ; 117(5): 1096-1106, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37393022

RESUMO

PURPOSE: The TOPGEAR phase 3 trial hypothesized that adding preoperative chemoradiation therapy (CRT) to perioperative chemotherapy will improve survival in patients with gastric cancer. Owing to the complexity of gastric irradiation, a comprehensive radiation therapy quality assurance (RTQA) program was implemented. Our objective is to describe the RTQA methods and outcomes. METHODS AND MATERIALS: RTQA was undertaken in real time before treatment for the first 5 patients randomized to CRT from each center. Once acceptable quality was achieved, RTQA was completed for one-third of subsequent cases. RTQA consisted of evaluating (1) clinical target volume and organ-at-risk contouring and (2) radiation therapy planning parameters. Protocol violations between high- (20+ patients enrolled) and low-volume centers were compared using the Fisher exact test. RESULTS: TOPGEAR enrolled 574 patients, of whom 286 were randomized to receive preoperative CRT and 203 (71%) were included for RTQA. Of these, 67 (33%) and 136 (67%) patients were from high- and low-volume centers, respectively. The initial RTQA pass rate was 72%. In total, 28% of cases required resubmission. In total, 200 of 203 cases (99%) passed RTQA before treatment. Cases from low-volume centers required resubmission more often (44/136 [33%] vs 13/67 [18%]; P = .078). There was no change in the proportion of cases requiring resubmission over time. Most cases requiring resubmission had multiple protocol violations. At least 1 aspect of the clinical target volume had to be adjusted in all cases. Inadequate coverage of the duodenum was most common (53% major violation, 25% minor violation). For the remaining cases, the resubmission process was triggered secondary to poor contour/plan quality. CONCLUSIONS: In a large multicenter trial, RTQA is feasible and effective in achieving high-quality treatment plans. Ongoing education should be performed to ensure consistent quality during the entire study period.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/terapia , Terapia Neoadjuvante , Estudos de Viabilidade , Garantia da Qualidade dos Cuidados de Saúde , Quimiorradioterapia
20.
Cancer Med ; 12(15): 16019-16031, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37329221

RESUMO

BACKGROUND: Trials of tyrosine kinase inhibitors (TKI) have not demonstrated dramatic benefits in advanced colorectal cancer (CRC), and this may be a function of poor patient selection. TKI-induced hypertension is reportedly a surrogate marker for treatment benefit for some tumor types. Our objective was to determine whether hypertension was associated with benefit in the context of CRC treatment, and also to gain insight on the pathogenesis of TKI-induced hypertension by monitoring associated changes in the circulating metabolome. PATIENTS AND METHODS: Clinical data were acquired from clinical trial patients with metastatic CRC randomized to cetuximab ± the TKI brivanib (N = 750). Outcomes were evaluated as a function of treatment-induced hypertension. For metabolomic studies, plasma samples were taken at baseline, as well as at 1, 4, and 12 weeks after treatment initiation. Samples were submitted to gas chromatography-mass spectrometry to identify treatment-related metabolomic changes associated with TKI-induced hypertension, compared to pre-treatment baseline. A model based on changes in metabolite concentrations was generated using orthogonal partial least squares discriminant analysis (OPLS-DA). RESULTS: In the brivanib treated group, 95 patients had treatment-related hypertension within 12 weeks of initiating treatment. TKI-induced hypertension was not associated with a significantly higher response rate, nor was it associated with improved progression-free or overall survival. In metabolomic studies, 386 metabolites were identified. There were 29 metabolites that changed with treatment and distinguished patients with and without TKI-induced hypertension. The OPLS-DA model for brivanib-induced hypertension was significant and robust (R2 Y score = 0.89, Q2 Y score = 0.70, CV-ANOVA = 2.01 e-7). Notable metabolomic features previously reported in pre-eclampsia and associated with vasoconstriction were found. CONCLUSION: TKI-induced hypertension was not associated with clinical benefit in metastatic CRC. We have identified changes in the metabolome that are associated with the development of worsening brivanib-induced hypertension that may be useful in future efforts of characterizing this toxicity.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , Metabolômica/métodos , Neoplasias Colorretais/patologia , Metaboloma , Triazinas/efeitos adversos
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