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1.
Ecol Lett ; 27(8): e14486, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39109607

RESUMEN

The Arctic is warming four times faster than the rest of the world, threatening the persistence of many Arctic species. It is uncertain if Arctic wildlife will have sufficient time to adapt to such rapidly warming environments. We used genetic forecasting to measure the risk of maladaptation to warming temperatures and sea ice loss in polar bears (Ursus maritimus) sampled across the Canadian Arctic. We found evidence for local adaptation to sea ice conditions and temperature. Forecasting of genome-environment mismatches for predicted climate scenarios suggested that polar bears in the Canadian high Arctic had the greatest risk of becoming maladapted to climate warming. While Canadian high Arctic bears may be the most likely to become maladapted, all polar bears face potentially negative outcomes to climate change. Given the importance of the sea ice habitat to polar bears, we expect that maladaptation to future warming is already widespread across Canada.


Asunto(s)
Cambio Climático , Ursidae , Ursidae/genética , Animales , Canadá , Regiones Árticas , Adaptación Fisiológica , Cubierta de Hielo , Ecosistema , Temperatura
2.
Br J Cancer ; 128(4): 549-555, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36434154

RESUMEN

BACKGROUND: Gastroenteropancreatic neuroendocrine neoplasms (GEPNENs) are heterogeneous in clinical course, biology, and outcomes. The NETPET score predicts survival by scoring uptake on dual [68Ga]DOTATATE and [18F]FDG PET/CT scans. We aimed to validate previous single-centre findings in a multicentre, international study. METHODS: Dual scans were assigned a NETPET score of P1 (DOTATATE positive/FDG negative), P2-4 (DOTATATE positive/FDG positive), or P5 (DOTATATE negative/FDG positive). NETPET score, histological grade, age at diagnosis, and presence/absence of extrahepatic disease were compared to overall survival/time to progression on univariate and multivariate analysis. RESULTS: 319 metastatic/unresectable GEPNEN patients were included. The NETPET score was significantly associated with overall survival and time to progression on univariate and multivariate analysis (all p < 0.01). Median overall survival/time to progression was 101.8/25.5 months for P1, 46.5/16.7 months for P2-4, and 11.5/6.6 months for P5. Histological grade correlated with overall survival and time to progression on univariate and multivariate analysis (all p < 0.01), while presence/absence of extrahepatic disease did not. Age at diagnosis correlated with overall survival on univariate and multivariate analysis (p < 0.01). The NETPET score also correlated with histological grade (p < 0.001). CONCLUSION: This study validates the NETPET score as a prognostic biomarker in metastatic GEPNENs, capturing the complexity of dual PET imaging.


Asunto(s)
Neoplasias Gastrointestinales , Tumores Neuroendocrinos , Compuestos Organometálicos , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Fluorodesoxiglucosa F18 , Radioisótopos de Galio , Tomografía de Emisión de Positrones , Tumores Neuroendocrinos/patología
3.
Curr Oncol Rep ; 25(2): 135-144, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36648705

RESUMEN

PURPOSE OF REVIEW: This review outlines the role of liver transplantation in selected patients with unresectable neuroendocrine tumour liver metastases. It discusses the international consensus on eligibility criteria and outlines the efforts taking place in the UK and Ireland to develop effective national liver transplant programmes for neuroendocrine tumour patients. RECENT FINDINGS: In the early history of liver transplantation, indications included cancer metastases to the liver as well as primaries of liver origin. Often, liver transplantation was a salvage procedure. The early results were disappointing, including in patients with neuroendocrine tumours. These data discouraged the widespread adoption of liver transplantation for neuroendocrine tumour liver metastases (NET LM). A few centres persisted in performing liver transplantation for patients with NET LM and in determining parameters predictive of good outcomes. Their work has provided evidence for benefit of liver transplantation in a selected group of patients with NET LM. Liver transplantation for NET LM is now accepted as a valid indication by many professional bodies, including the European Neuroendocrine Tumour Society (ENETS) and the United Network for Organ Sharing (UNOS). It is nevertheless rarely utilised. The UK and the Republic of Ireland are commencing a pilot programme of liver transplantation in selected patients. This programme will help develop the expertise and infrastructure to make liver transplantation for NET LM a routine procedure.


Asunto(s)
Neoplasias Hepáticas , Trasplante de Hígado , Tumores Neuroendocrinos , Humanos , Tumores Neuroendocrinos/cirugía , Tumores Neuroendocrinos/patología , Neoplasias Hepáticas/secundario
4.
Curr Oncol Rep ; 24(10): 1281-1286, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35554845

RESUMEN

PURPOSE OF REVIEW: Mesenteric desmoplasia in small intestinal neuroendocrine neoplasms (SINENs) is associated with increased morbidity and mortality. In this paper, we discuss the development of desmoplasia in SINENs. RECENT FINDINGS: The fibrotic reactions associated with these tumours could be limited to the loco-regional environment of the tumour and/or at distant sites. Mesenteric fibrotic mass forms around a local lymph node. Formation of desmoplasia is mediated by interactions between the neoplastic cells and its microenvironment via number of profibrotic mediators and signalling pathways. Profibrotic molecules that are mainly involved in the desmoplastic reaction include serotonin, TGFß (transforming growth factor ß) and CTGF (connective tissue growth factor), although there is some evidence to suggest that there are a number of other molecules involved in this process. Desmoplasia is a result of autocrine and paracrine effects of multiple molecules and signalling pathways. However, more research is needed to understand these mechanisms and to develop targeted therapy to minimise desmoplasia.


Asunto(s)
Neoplasias Intestinales , Tumores Neuroendocrinos , Fibrosis , Humanos , Neoplasias Intestinales/patología , Tumores Neuroendocrinos/patología , Transducción de Señal , Microambiente Tumoral
5.
Lancet Oncol ; 22(12): 1752-1763, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34793718

RESUMEN

BACKGROUND: The primary analysis of the phase 3 NETTER-1 trial showed significant improvement in progression-free survival with 177Lu-Dotatate plus long-acting octreotide versus high-dose long-acting octreotide alone in patients with advanced midgut neuroendocrine tumours. Here, we report the prespecified final analysis of overall survival and long-term safety results. METHODS: This open-label, randomised, phase 3 trial enrolled patients from 41 sites in eight countries across Europe and the USA. Patients were 18 years and older with locally advanced or metastatic, well differentiated, somatostatin receptor-positive midgut neuroendocrine tumours (Karnofsky performance status score ≥60) and disease progression on fixed-dose long-acting octreotide. Patients were randomly assigned (1:1) via an interactive web-based response system to intravenous 177Lu-Dotatate 7·4 GBq (200 mCi) every 8 weeks (four cycles) plus intramuscular long-acting octreotide 30 mg (177Lu-Dotatate group) or high-dose long-acting octreotide 60 mg every 4 weeks (control group). The primary endpoint of progression-free survival has been previously reported; here, we report the key secondary endpoint of overall survival in the intention-to-treat population. Final overall survival analysis was prespecified to occur either after 158 deaths or 5 years after the last patient was randomised, whichever occurred first. During long-term follow-up, adverse events of special interest were reported in the 177Lu-Dotatate group only. This trial is registered with ClinicalTrials.gov, NCT01578239. FINDINGS: From Sept 6, 2012, to Jan 14, 2016, 231 patients were enrolled and randomly assigned for treatment. The prespecified final analysis occurred 5 years after the last patient was randomly assigned (when 142 deaths had occurred); median follow-up was 76·3 months (range 0·4-95·0) in the 177Lu-Dotatate group and 76·5 months (0·1-92·3) in the control group. The secondary endpoint of overall survival was not met: median overall survival was 48·0 months (95% CI 37·4-55·2) in the 177Lu-Dotatate group and 36·3 months (25·9-51·7) in the control group (HR 0·84 [95% CI 0·60-1·17]; two-sided p=0·30). During long-term follow-up, treatment-related serious adverse events of grade 3 or worse were recorded in three (3%) of 111 patients in the 177Lu-Dotatate group, but no new treatment-related serious adverse events were reported after the safety analysis cutoff. Two (2%) of 111 patients given 177Lu-Dotatate developed myelodysplastic syndrome, one of whom died 33 months after randomisation (this person was the only the only reported 177Lu-Dotatate treatment-related death). No new cases of myelodysplastic syndrome or acute myeloid leukaemia were reported during long-term follow-up. INTERPRETATION: 177Lu-Dotatate treatment did not significantly improve median overall survival versus high-dose long-acting octreotide. Despite final overall survival not reaching statistical significance, the 11·7 month difference in median overall survival with 177Lu-Dotatate treatment versus high-dose long-acting octreotide alone might be considered clinically relevant. No new safety signals were reported during long-term follow-up. FUNDING: Advanced Accelerator Applications, a Novartis company.


Asunto(s)
Quimioradioterapia/mortalidad , Neoplasias del Sistema Digestivo/mortalidad , Tumores Neuroendocrinos/mortalidad , Octreótido/análogos & derivados , Octreótido/uso terapéutico , Compuestos Organometálicos/uso terapéutico , Anciano , Antineoplásicos Hormonales/uso terapéutico , Neoplasias del Sistema Digestivo/patología , Neoplasias del Sistema Digestivo/terapia , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Masculino , Tumores Neuroendocrinos/patología , Tumores Neuroendocrinos/terapia , Pronóstico , Radiofármacos/uso terapéutico , Tasa de Supervivencia
6.
Eur J Nucl Med Mol Imaging ; 48(11): 3582-3594, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33835221

RESUMEN

PURPOSE: The safety and efficacy of 177Lu-DOTATATE in older patients with advanced neuroendocrine tumours (NET) are not well understood. METHODS: Patients ≥70 years of age and treated with 177Lu-DOTATATE were included. Toxicity, health-related quality of life (HRQoL), objective response, progression-free survival (PFS) and overall survival (OS) were assessed. The relationship between baseline characteristics and PFS and OS was analysed using the Kaplan-Meier method. Univariate analyses were performed using the Cox proportional hazards model. RESULTS: In total, 71 patients were included (76.1% midgut primary). The median age at diagnosis and age at 177Lu-DOTATATE treatment were 70 and 74 years, respectively. The majority (78.9%) of patients completed 4 cycles of 177Lu-DOTATATE. Clinically significant myelosuppression was rare (2.8%). There was no deterioration in HRQoL and 'disease-specific worries' significantly improved (P = 0.029). Radiological response assessment was available in 66 patients. Partial response, stable disease and progression of disease were found in 10 (15.2%), 52 (78.8%) and 4 patients (6.1%), respectively. Median PFS and OS were 36.0 and 47.0 months, respectively. Increased baseline alkaline phosphatase was associated with poorer PFS (P = 0.002) and OS (P = 0.006). CONCLUSION: Patients ≥70 years of age with advanced NET treated with 177Lu-DOTATATE have efficacy and toxicity profiles similar to the wider NET population, without deterioration of HRQoL.


Asunto(s)
Tumores Neuroendocrinos , Compuestos Organometálicos , Anciano , Humanos , Tumores Neuroendocrinos/radioterapia , Octreótido/efectos adversos , Compuestos Organometálicos/efectos adversos , Calidad de Vida , Radiofármacos
7.
Neuroendocrinology ; 111(9): 863-875, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32950978

RESUMEN

BACKGROUND: The number of therapeutic options for patients with pancreatic neuroendocrine neoplasms (PNEN) has increased, but the optimal therapeutic algorithm has not been defined due to lack of randomised trials comparing different modalities. METHODS: We performed a retrospective study in patients with metastatic PNEN treated with ≥1 line of systemic therapy. The relationship between baseline characteristics, treatment type, and time to treatment failure (TTF), time to progression (TTP), and overall survival (OS) was analysed using the Kaplan-Meier method. Univariate and multivariate analyses were performed using the Cox proportional hazards model. RESULTS: Two hundred and fifty-five patients with metastatic PNEN had 491 evaluable lines of therapy. Independent predictors of TTF included treatment type, Ki-67, tumour grade, and chromogranin A. To reduce selection bias, a subgroup of 114 patients with grade 2 (G2) metastatic pancreatic neuroendocrine tumours (PNET) was analysed separately. These patients had received 234 lines of treatment (105 chemotherapy, 82 molecular targeted therapy, and 47 peptide receptor radionuclide therapy [PRRT]). In the G2 cohort, TTF and TTP were superior for PRRT compared with both chemotherapy and molecular targeted therapy. OS in the G2 cohort was also superior for those that had received PRRT compared with those that had not (median 84 vs. 56 months; HR 0.55, 95% CI: 0.31-0.98, p = 0.04). CONCLUSIONS: This study suggests that PRRT is associated with superior clinical outcomes relative to other systemic therapies for G2 metastatic PNET. Prospective studies are required to confirm these observations.


Asunto(s)
Algoritmos , Antineoplásicos/farmacología , Terapia Molecular Dirigida , Tumores Neuroendocrinos/terapia , Evaluación de Resultado en la Atención de Salud , Neoplasias Pancreáticas/terapia , Radioterapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/secundario , Neoplasias Pancreáticas/secundario , Estudios Retrospectivos , Adulto Joven
8.
Anticancer Drugs ; 31(3): 216-222, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31977567

RESUMEN

Accessible prognostic tools are needed to individualize treatment of neuroendocrine tumors (NETs). Data suggest neutrophil/lymphocyte ratios (NLRs) have prognostic value in some solid tumors, including NETs. In the randomized double-blind CLARINET study (NCT00353496; EudraCT 2005-004904-35), the somatostatin analog lanreotide autogel/depot increased progression-free survival (PFS) compared with placebo in patients with inoperable or metastatic intestinal and pancreatic NETs (grades 1-2, Ki-67 < 10%). The exploratory post-hoc analyses presented here evaluated the prognostic value of NLR in the CLARINET study cohort, in the context of and independently from treatment. Kaplan-Meier PFS plots were generated for patients with available NLR data, in subgroups based on NLR values, and 24-month survival rates were calculated. P values and hazard ratios for prognostic effects were generated using Cox models. 31216222 Baseline characteristics were balanced between lanreotide autogel/depot 120 mg (n = 100) and placebo (n = 101) arms. Irrespective of treatment, raw 24-month PFS rates were comparable across subgroups based on NLR tertiles [37.3% (low), 38.8% (middle), 38.8% (high); n = 67 per group] and NLR cutoff of 4 [38.1% (NLR ≤ 4; n = 176), 40.0% (NLR > 4; n = 25)]. Furthermore, NLRs were not prognostic in Cox models, irrespective of subgroups used. The therapeutic effect of lanreotide autogel/depot 120 mg was independent of NLRs (P > 0.1). These exploratory post-hoc analyses in patients with advanced intestinal and pancreatic NETs contrast with previous data suggesting NLR has prognostic potential in NETs. This may reflect the inclusion of patients with lower-grade tumors or use of higher NLR cutoff values in the current analysis.


Asunto(s)
Linfocitos , Tumores Neuroendocrinos/mortalidad , Neutrófilos , Neoplasias Pancreáticas/mortalidad , Anciano , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/sangre , Neoplasias Pancreáticas/sangre , Pronóstico , Modelos de Riesgos Proporcionales
9.
Analyst ; 145(2): 402-414, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31755482

RESUMEN

We report the development of a dual-enzyme electrochemical biosensor based on microfabricated gold band array electrodes which were first modified by gold foam (Au-foam) in order to dramatically increase the active surface area. The resulting nanostructured Au-foam deposits then served as a highly porous 3D matrix for the electrodeposition of a nanocomposite film consisting of multi walled carbon nanotubes embedded in a chitosan matrix (CS:MWCNT) designed to provide a conducting, biocompatible and chemically versatile surface suitable for the attachment of a wide range of chemically or biologically active agents. Finally, a dual enzyme mixture of glucose oxidase (GOx) and horseradish peroxidase (HRP) was immobilised onto the CS:MWCNT nanocomposite film surface. It is shown that the resulting sensing platform developed demonstrates excellent analytical performance in terms of glucose detection with a sensitivity of 261.8 µA mM-1 cm-2 and a reproducibility standard deviation (RSD) of 3.30% as determined over 7 measurements. Furthermore, long term stability studies showed that the electrodes exhibited an effectively unchanged response to glucose detection after some 45 days. The example of glucose detection presented here illustrates the fact that the particular combination of nanostructured materials employed represents a very flexible platform for the attachment of enzymes or indeed any other bioactive agent and as such may form the basis of the fabrication of a wide range of biosensors. Finally, since the platform used is based on lithographically-deposited gold electrodes on silicon, we note that it is also very suitable for further miniaturisation, mass production and packaging- all of which would serve to reduce production costs.


Asunto(s)
Técnicas Biosensibles/métodos , Quitosano/química , Enzimas Inmovilizadas/química , Glucosa/análisis , Nanotubos de Carbono/química , Armoracia/enzimología , Aspergillus niger/enzimología , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Electrodos , Glucosa/química , Glucosa Oxidasa/química , Oro/química , Peroxidasa de Rábano Silvestre/química , Límite de Detección , Oxidación-Reducción , Reproducibilidad de los Resultados
10.
Sensors (Basel) ; 20(21)2020 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-33113948

RESUMEN

The research field of glucose biosensing has shown remarkable growth and development since the first reported enzyme electrode in 1962. Extensive research on various immobilization methods and the improvement of electron transfer efficiency between the enzyme and the electrode have led to the development of various sensing platforms that have been constantly evolving with the invention of advanced nanostructures and their nano-composites. Examples of such nanomaterials or composites include gold nanoparticles, carbon nanotubes, carbon/graphene quantum dots and chitosan hydrogel composites, all of which have been exploited due to their contributions as components of a biosensor either for improving the immobilization process or for their electrocatalytic activity towards glucose. This review aims to summarize the evolution of the biosensing aspect of these glucose sensors in terms of the various generations and recent trends based on the use of applied nanostructures for glucose detection in the presence and absence of the enzyme. We describe the history of these biosensors based on commercialized systems, improvements in the understanding of the surface science for enhanced electron transfer, the various sensing platforms developed in the presence of the nanomaterials and their performances.


Asunto(s)
Técnicas Biosensibles , Glucosa , Nanopartículas del Metal , Nanotubos de Carbono , Técnicas Electroquímicas , Glucosa/análisis , Oro
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