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1.
Nat Immunol ; 18(8): 940-950, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28628092

RESUMEN

Therapies that boost the anti-tumor responses of cytotoxic T lymphocytes (CTLs) have shown promise; however, clinical responses to the immunotherapeutic agents currently available vary considerably, and the molecular basis of this is unclear. We performed transcriptomic profiling of tumor-infiltrating CTLs from treatment-naive patients with lung cancer to define the molecular features associated with the robustness of anti-tumor immune responses. We observed considerable heterogeneity in the expression of molecules associated with activation of the T cell antigen receptor (TCR) and of immunological-checkpoint molecules such as 4-1BB, PD-1 and TIM-3. Tumors with a high density of CTLs showed enrichment for transcripts linked to tissue-resident memory cells (TRM cells), such as CD103, and CTLs from CD103hi tumors displayed features of enhanced cytotoxicity. A greater density of TRM cells in tumors was predictive of a better survival outcome in lung cancer, and this effect was independent of that conferred by CTL density. Here we define the 'molecular fingerprint' of tumor-infiltrating CTLs and identify potentially new targets for immunotherapy.


Asunto(s)
Adenocarcinoma/inmunología , Carcinoma de Células Escamosas/inmunología , Neoplasias de Cabeza y Cuello/inmunología , Memoria Inmunológica/inmunología , Neoplasias Pulmonares/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos T Citotóxicos/inmunología , Adenocarcinoma/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD/genética , Carcinoma de Células Escamosas/mortalidad , Femenino , Perfilación de la Expresión Génica , Receptor 2 Celular del Virus de la Hepatitis A/genética , Humanos , Inmunoterapia , Cadenas alfa de Integrinas/genética , Neoplasias Pulmonares/mortalidad , Linfocitos Infiltrantes de Tumor/metabolismo , Masculino , Persona de Mediana Edad , Pronóstico , Receptor de Muerte Celular Programada 1/genética , Receptores de Antígenos de Linfocitos T/genética , Carcinoma de Células Escamosas de Cabeza y Cuello , Tasa de Supervivencia , Linfocitos T Citotóxicos/metabolismo , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/genética
2.
Nature ; 605(7911): 741-746, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35508656

RESUMEN

Phosphoinositide 3-kinase δ (PI3Kδ) has a key role in lymphocytes, and inhibitors that target this PI3K have been approved for treatment of B cell malignancies1-3. Although studies in mouse models of solid tumours have demonstrated that PI3Kδ inhibitors (PI3Kδi) can induce anti-tumour immunity4,5, its effect on solid tumours in humans remains unclear. Here we assessed the effects of the PI3Kδi AMG319 in human patients with head and neck cancer in a neoadjuvant, double-blind, placebo-controlled randomized phase II trial (EudraCT no. 2014-004388-20). PI3Kδ inhibition decreased the number of tumour-infiltrating regulatory T (Treg) cells and enhanced the cytotoxic potential of tumour-infiltrating T cells. At the tested doses of AMG319, immune-related adverse events (irAEs) required treatment to be discontinued in 12 out of 21 of patients treated with AMG319, suggestive of systemic effects on Treg cells. Accordingly, in mouse models, PI3Kδi decreased the number of Treg cells systemically and caused colitis. Single-cell RNA-sequencing analysis revealed a PI3Kδi-driven loss of tissue-resident colonic ST2 Treg cells, accompanied by expansion of pathogenic T helper 17 (TH17) and type 17 CD8+ T (TC17) cells, which probably contributed to toxicity; this points towards a specific mode of action for the emergence of irAEs. A modified treatment regimen with intermittent dosing of PI3Kδi in mouse models led to a significant decrease in tumour growth without inducing pathogenic T cells in colonic tissue, indicating that alternative dosing regimens might limit toxicity.


Asunto(s)
Antineoplásicos , Neoplasias de Cabeza y Cuello , Adenosina/uso terapéutico , Animales , Antineoplásicos/uso terapéutico , Modelos Animales de Enfermedad , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Humanos , Inmunoterapia , Ratones , Fosfatidilinositol 3-Quinasas , Quinolinas/uso terapéutico , Linfocitos T Reguladores
3.
J Biol Chem ; 300(9): 107696, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39168183

RESUMEN

An ever-growing number of studies highlight the importance of S-acylation, a reversible protein-lipid modification, for diverse aspects of intracellular signaling. In this review, we summarize the current understanding of how S-acylation regulates perhaps the best-known class of signaling enzymes, protein kinases. We describe how S-acylation acts as a membrane targeting signal that localizes certain kinases to specific membranes, and how such membrane localization in turn facilitates the assembly of signaling hubs consisting of an S-acylated kinase's upstream activators and/or downstream targets. We further discuss recent findings that S-acylation can control additional aspects of the function of certain kinases, including their interactions and, surprisingly, their activity, and how such regulation might be exploited for potential therapeutic gain. We go on to describe the roles and regulation of de-S-acylases and how extracellular signals drive dynamic (de)S-acylation of certain kinases. We discuss how S-acylation has the potential to lead to "emergent properties" that alter the temporal profile and/or salience of intracellular signaling events. We close by giving examples of other S-acylation-dependent classes of signaling enzymes and by discussing how recent biological and technological advances should facilitate future studies into the functional roles of S-acylation-dependent signaling.


Asunto(s)
Transducción de Señal , Acilación , Humanos , Animales , Proteínas Quinasas/metabolismo , Membrana Celular/metabolismo
4.
J Biol Chem ; 299(8): 104965, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37356718

RESUMEN

Janus Kinase-1 (JAK1) plays key roles during neurodevelopment and following neuronal injury, while activatory JAK1 mutations are linked to leukemia. In mice, Jak1 genetic deletion results in perinatal lethality, suggesting non-redundant roles and/or regulation of JAK1 for which other JAKs cannot compensate. Proteomic studies reveal that JAK1 is more likely palmitoylated compared to other JAKs, implicating palmitoylation as a possible JAK1-specific regulatory mechanism. However, the importance of palmitoylation for JAK1 signaling has not been addressed. Here, we report that JAK1 is palmitoylated in transfected HEK293T cells and endogenously in cultured Dorsal Root Ganglion (DRG) neurons. We further use comprehensive screening in transfected non-neuronal cells and shRNA-mediated knockdown in DRG neurons to identify the related enzymes ZDHHC3 and ZDHHC7 as dominant protein acyltransferases (PATs) for JAK1. Surprisingly, we found palmitoylation minimally affects JAK1 localization in neurons, but is critical for JAK1's kinase activity in cells and even in vitro. We propose this requirement is likely because palmitoylation facilitates transphosphorylation of key sites in JAK1's activation loop, a possibility consistent with structural models of JAK1. Importantly, we demonstrate a leukemia-associated JAK1 mutation overrides the palmitoylation-dependence of JAK1 activity, potentially explaining why this mutation is oncogenic. Finally, we show that JAK1 palmitoylation is important for neuropoietic cytokine-dependent signaling and neuronal survival and that combined Zdhhc3/7 loss phenocopies loss of palmitoyl-JAK1. These findings provide new insights into the control of JAK signaling in both physiological and pathological contexts.


Asunto(s)
Citocinas , Lipoilación , Neuronas , Transducción de Señal , Animales , Femenino , Humanos , Ratones , Embarazo , Citocinas/metabolismo , Ganglios Espinales/metabolismo , Células HEK293 , Janus Quinasa 1/genética , Janus Quinasa 1/metabolismo , Neuronas/citología , Neuronas/metabolismo , Proteómica , Supervivencia Celular
5.
J Chem Ecol ; 50(3-4): 85-99, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38246946

RESUMEN

Polydimethylsiloxane (PDMS) tubing is increasingly being used to collect volatile organic compounds (VOCs) from static biological headspace. However, analysis of VOCs collected using PDMS tubing often deploys thermal desorption, where samples are considered as 'one-offs' and cannot be used in multiple experiments. In this study, we developed a static headspace VOC collection method using PDMS tubing which is solvent-based, meaning that VOC extracts can be used multiple times and can be linked to biological activity. Using a synthetic blend containing a range of known semiochemicals (allyl isothiocyanate, (Z)-3-hexen-1-ol, 1-octen-3-one, nonanal, (E)-anethol, (S)-bornyl acetate, (E)-caryophyllene and pentadecane) with differing chemical and physicochemical properties, VOCs were collected in static headspace by exposure to PDMS tubing with differing doses, sampling times and lengths. In a second experiment, VOCs from oranges were collected using PDMS sampling of static headspace versus dynamic headspace collection. VOCs were eluted with diethyl ether and analysed using gas chromatography - flame ionization detector (GC-FID) and coupled GC - mass spectrometry. GC-FID analysis of collected samples showed that longer PDMS tubes captured significantly greater quantities of compounds than shorter tubes, and that sampling duration significantly altered the recovery of all tested compounds. Moreover, greater quantities of compounds were recovered from closed compared to open systems. Finally, analysis of orange headspace VOCs showed no qualitative differences in VOCs recovered compared to dynamic headspace collections, although quantities sampled using PDMS tubing were lower. In summary, extraction of PDMS tubing with diethyl ether solvent captures VOCs from the headspace of synthetic blends and biological samples, and the resulting extracts can be used for multiple experiments linking VOC content to biological activity.


Asunto(s)
Dimetilpolisiloxanos , Solventes , Compuestos Orgánicos Volátiles , Dimetilpolisiloxanos/química , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/química , Solventes/química , Cromatografía de Gases y Espectrometría de Masas
6.
Sociol Health Illn ; 45(6): 1223-1241, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36181509

RESUMEN

The 'expressivist objection' (EO) refers to the notion that using reproductive (genetic) technologies to prevent the birth of future would-be disabled people contain, and express, a negative valuation of life with disability. Whilst the EO has received increased attention in recent years in line with rapid technological and genomic developments, there remains scant research on how EO concerns are experienced and expressed by disabled people and their families, especially within and between impairment groups. Bringing together two studies-one with adults and family members living with genetic conditions (n = 62) and one with parents of children with Down's syndrome (n = 22)-we argue that disabled people and their families variously embrace, reject or rework the EO across contexts, and yet also frequently situate it within broad support for reproductive technologies. We present three key factors that mediate responses to the EO: (1) the nature of impairment and its integration within identity; (2) social and cultural contexts relating to disability and (3) the (individual and collective) imagined futures of disabled people. In so doing, we blend the conceptual architecture of medical sociology and disability studies, arguing that this allows us to accurately illuminate the nuanced responses of disabled people and their families.


Asunto(s)
Personas con Discapacidad , Síndrome de Down , Embarazo , Femenino , Adulto , Niño , Humanos , Diagnóstico Prenatal , Síndrome de Down/diagnóstico , Síndrome de Down/genética , Familia , Padres
7.
J Cardiovasc Electrophysiol ; 33(1): 7-16, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34797600

RESUMEN

INTRODUCTION: Before ablation, predicting the site of origin (SOO) of outflow tract ventricular arrhythmia (OTVA), can inform patient consent and facilitate appropriate procedural planning. We set out to determine if OTVA variability can accurately predict SOO. METHODS: Consecutive patients with a clear SOO identified at OTVA ablation had their prior 24-h ambulatory ECGs retrospectively analysed (derivation cohort). Percentage ventricular ectopic (VE) burden, hourly VE values, episodes of trigeminy/bigeminy, and the variability in these parameters were evaluated for their ability to distinguish right from left-sided SOO. Effective parameters were then prospectively tested on a validation cohort of consecutive patients undergoing their first OTVA ablation. RESULTS: High VE variability (coefficient of variation ≥0.7) and the presence of any hour with <50 VE, were found to accurately predict RVOT SOO in a derivation cohort of 40 patients. In a validation cohort of 29 patients, the correct SOO was prospectively identified in 23/29 patients (79.3%) using CoV, and 26/29 patients (89.7%) using VE < 50. Including current ECG algorithms, VE < 50 had the highest Youden Index (78), the highest positive predictive value (95.0%) and the highest negative predictive value (77.8%). CONCLUSION: VE variability and the presence of a single hour where VE < 50 can be used to accurately predict SOO in patients with OTVA. Accuracy of these parameters compares favorably to existing ECG algorithms.


Asunto(s)
Ablación por Catéter , Taquicardia Ventricular , Complejos Prematuros Ventriculares , Electrocardiografía , Ventrículos Cardíacos/cirugía , Humanos , Estudios Retrospectivos , Taquicardia Ventricular/cirugía
8.
Neuroendocrinology ; 112(4): 370-383, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34157710

RESUMEN

INTRODUCTION: Neuroendocrine tumours (NETs) are rare tumours with an increasing incidence. While low- and intermediate-grade pancreatic NET (PanNET) and small intestinal NET (siNET) are slow growing, they have a relatively high rate of metastasizing to the liver, leading to substantially worse outcomes. In many solid tumours, the outcome is determined by the quality of the antitumour immune response. However, the quality and significance of antitumour responses in NETs are incompletely understood. This study provides clinico-pathological analyses of the tumour immune microenvironment in PanNET and siNETs. METHODS: Formalin-fixed paraffin-embedded tissue from consecutive resected PanNETs (61) and siNETs (131) was used to construct tissue microarrays (TMAs); 1-mm cores were taken from the tumour centre, stroma, tumour edge, and adjacent healthy tissue. TMAs were stained with antibodies against CD8, CD4, CD68, FoxP3, CD20, and NCR1. T-cell counts were compared with counts from lung cancers. RESULTS: For PanNET, median counts were CD8+ 35.4 cells/mm2, CD4+ 7.6 cells/mm2, and CD68+ macrophages 117.7 cells/mm2. For siNET, there were CD8+ 39.2 cells/mm2, CD4+ 24.1 cells/mm2, and CD68+ 139.2 cells/mm2. The CD8+ cell density in the tumour and liver metastases were significantly lower than in the adjacent normal tissues, without evidence of a cell-rich area at the tumour edge that might have suggested immune exclusion. T-cell counts in lung cancer were significantly higher than those in PanNET and siNETs: CD8+ 541 cells/mm2 and CD4+ 861 cells/mm2 (p ≤ 0.0001). CONCLUSION: PanNETs and siNETs are immune cold with no evidence of T cell exclusion; the low density of immune infiltrates indicates poor antitumour immune responses.


Asunto(s)
Tumores Neuroendocrinos , Neoplasias Pancreáticas , Neoplasias Gástricas , Humanos , Tumores Neuroendocrinos/patología , Neoplasias Pancreáticas/patología , Pronóstico , Microambiente Tumoral
9.
Med Humanit ; 48(1): 123-132, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34479988

RESUMEN

Disability remains on the margins of the social sciences. Even where disability is foregrounded as a category of analysis, accounts regularly emerge in silos, with little interdisciplinary dialogue acknowledging the potential intersections and points of convergence. This discord is particularly acute within medical sociology and disability studies, yet there is mostly a legacy of silence about the relationship between the two disciplines. Drawing upon data from a qualitative study with parents of disabled children in the UK, I show the value of meshing ideas and tropes from medical sociology and disability studies to make sense of parents' lived experiences. They described the challenges of living with 'impairment' and a need to readjust expectations. At the same time, parents were keen to not align with a deficit framing of their lives. They talked in affirmative terms about their children as sources of joy and vitality, perceived themselves as 'normal', and described convivial, even unremarkable, interactions in public spaces. Yet, parents encountered difficulties when navigating institutional settings and bureaucratic arrangements, or what was commonly referred to as 'the system'. Their troubles were not located in their children's bodies, but in-as per a disability studies sensibility-cultural and structural systems preventing their capacity to live well I argue that both disability studies and medical sociology offer something to the analysis, thereby recognising the gains of not simply buying into the tradition of one worldview. I conclude by imploring for more concrete conversations between both disciplines.


Asunto(s)
Personas con Discapacidad , Sociología Médica , Niño , Estudios de la Discapacidad , Humanos , Padres , Investigación Cualitativa
10.
Res Sports Med ; 30(4): 343-352, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33938338

RESUMEN

This case summarizes the rehabilitation and return to play management of a 17-year-old elite male soccer player who required surgical stabilization of an Osteochondritis Dissecans (OCD) lesion of the trochlea groove. Trochlea groove lesions represent <1% of OCD cases, resulting in limited evidence to inform practice. The case was initially identified as antalgic running gait, and at this point the player revealed progressively worsening knee pain (over preceding 2 months) which presented as patellofemoral pain with a small knee effusion and quadriceps atrophy present on assessment. No improvement in symptoms after 2 weeks of unloading (no running) and traditional patellofemoral treatment prompted magnetic resonance imaging and computed tomography scans to inform surgical intervention. We present a summary of the four-stage rehabilitation process defined by objective assessments, resulting in a successful return-to-play 24 weeks post-surgery. This case advocates consideration of OCD in the assessment of persistent knee pain in young athletes.


Asunto(s)
Osteocondritis Disecante , Fútbol , Adolescente , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Masculino , Osteocondritis Disecante/diagnóstico por imagen , Osteocondritis Disecante/cirugía , Dolor/etiología , Dolor/patología , Volver al Deporte
11.
J Biol Chem ; 295(46): 15427-15437, 2020 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-32958558

RESUMEN

Palmitoylation, the modification of proteins with the lipid palmitate, is a key regulator of protein targeting and trafficking. However, knowledge of the roles of specific palmitoyl acyltransferases (PATs), which catalyze palmitoylation, is incomplete. For example, little is known about which PATs are present in neuronal axons, although long-distance trafficking of palmitoyl-proteins is important for axon integrity and for axon-to-soma retrograde signaling, a process critical for axon development and for responses to injury. Identifying axonally targeted PATs might thus provide insights into multiple aspects of axonal biology. We therefore comprehensively determined the subcellular distribution of mammalian PATs in dorsal root ganglion (DRG) neurons and, strikingly, found that only two PATs, ZDHHC5 and ZDHHC8, were enriched in DRG axons. Signals via the Gp130/JAK/STAT3 and DLK/JNK pathways are important for axonal injury responses, and we found that ZDHHC5 and ZDHHC8 were required for Gp130/JAK/STAT3, but not DLK/JNK, axon-to-soma signaling. ZDHHC5 and ZDHHC8 robustly palmitoylated Gp130 in cotransfected nonneuronal cells, supporting the possibility that Gp130 is a direct ZDHHC5/8 substrate. In DRG neurons, Zdhhc5/8 shRNA knockdown reduced Gp130 palmitoylation and even more markedly reduced Gp130 surface expression, potentially explaining the importance of these PATs for Gp130-dependent signaling. Together, these findings provide new insights into the subcellular distribution and roles of specific PATs and reveal a novel mechanism by which palmitoylation controls axonal retrograde signaling.


Asunto(s)
Aciltransferasas/metabolismo , Axones/metabolismo , Transducción de Señal , Aciltransferasas/antagonistas & inhibidores , Aciltransferasas/genética , Animales , Células Cultivadas , Receptor gp130 de Citocinas/genética , Receptor gp130 de Citocinas/metabolismo , Ganglios Espinales/citología , Ganglios Espinales/metabolismo , Expresión Génica , Células HEK293 , Humanos , Quinasas Janus/metabolismo , Lipoilación , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Ratas , Factor de Transcripción STAT3/metabolismo
12.
Acad Psychiatry ; 45(3): 315-321, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33409939

RESUMEN

OBJECTIVE: Barriers and facilitators of evidence-based practice (EBP) in psychiatrists in training have only been researched with reference to prescribing decisions. We sought to quantitatively describe general EBP barriers and facilitators perceived by psychiatry core trainees (CTs) in England. METHODS: A cross-sectional survey of CTs from a single English region in their 1st to 3rd year of specialist training (CT1-3) uses the EBP inventory, a 26-item questionnaire subdivided into the domains of attitudes, social norms, perceived behavioral control (PBC), decision-making preferences, and intention and behavior. This was analyzed using a multiple indicators multiple causes model. RESULTS: The response rate was 42.9% (72/168 CTs). In all, domain's responses overall tended to be positive toward EBP. The most commonly reported barriers were rarely discussing research literature, feeling incapable of staying up to date, aversion to statistics, a preference for intuition or experience, and a perception that EBP disregards the individual differences between patients. Attitudes, norms, and behavior all loaded onto their intended factors. The decision-making factor was not present and PBC subdivided into 2 factors: clinical and knowledge self-efficacy. Regression coefficients for predicting behavior from the other factors were attitudes - 0.16 (p = 0.34), norms 0.34 (p = 0.24), clinical PBC - 0.28 (p = 0.10), and knowledge PBC 0.613 (p = 0.01). Additionally, question 5 (EBP respects individual patients) and question 13 (discusses research literature with colleagues) independently predicted behavior (ß = 0.388; p = 0.05 and ß = 0.433; p = 0.01). CONCLUSIONS: EBP intention and behavior were associated with perceiving EBP as relevant to individual patients, discussion about research with colleagues, and knowledge self-efficacy.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Psiquiatría , Actitud del Personal de Salud , Estudios Transversales , Inglaterra , Práctica Clínica Basada en la Evidencia , Humanos , Encuestas y Cuestionarios
13.
Br J Sociol ; 72(3): 693-706, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33368162

RESUMEN

While disability has historically been depicted in problematic ways in television, film, and print media, more balanced and progressive cultural representations are arguably emerging. However, few studies address how disabled people and their families (e.g., parents) encounter, and make sense of, media configurations ostensibly designed to promote a more positive and visible image of living with disability. Drawing upon interviews with parents of children with Down's syndrome in the United Kingdom, I sketch out how they feel about depictions that, arguably, depart from hurtful historical narratives of disability as tragic and pitiable. Parents praise, and mostly embrace, recent portrayals of people with Down's syndrome in media outputs. At the same time, they raise concerns around tokenism, stereotyping, focusing upon "exceptional" people, and fueling sanitized accounts which deny, or at least obscure, the harsh lived realities for many parents of disabled children. I conclude by arguing that while parents largely applaud and welcome positive public narratives, they also fear that such representations threaten to gloss over the pervasive mistreatment, disregard, and disenfranchisement of disabled people and their families.


Asunto(s)
Síndrome de Down , Medios de Comunicación de Masas , Estereotipo , Niño , Miedo , Humanos , Padres
14.
Br J Cancer ; 123(9): 1353-1355, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32830198
15.
Sensors (Basel) ; 20(24)2020 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-33322056

RESUMEN

Extreme fires in the peatlands of South East (SE) Asia are arguably the world's greatest biomass burning events, resulting in some of the worst ambient air pollution ever recorded (PM10 > 3000 µg·m-3). The worst of these fires coincide with El Niño related droughts, and include huge areas of smouldering combustion that can persist for months. However, areas of flaming surface vegetation combustion atop peat are also seen, and we show that the largest of these latter fires appear to be the most radiant and intensely smoke-emitting areas of combustion present in such extreme fire episodes. Fire emissions inventories and early warning of the air quality impacts of landscape fire are increasingly based on the fire radiative power (FRP) approach to fire emissions estimation, including for these SE Asia peatland fires. "Top-down" methods estimate total particulate matter emissions directly from FRP observations using so-called "smoke emission coefficients" [Ce; g·MJ-1], but currently no discrimination is made between fire types during such calculations. We show that for a subset of some of the most thermally radiant peatland fires seen during the 2015 El Niño, the most appropriate Ce is around a factor of three lower than currently assumed (~16.8 ± 1.6 g·MJ-1 vs. 52.4 g·MJ-1). Analysis indicates that this difference stems from these highly radiant fires containing areas of substantial flaming combustion, which changes the amount of particulate matter emitted per unit of observable fire radiative heat release in comparison to more smouldering dominated events. We also show that even a single one of these most radiant fires is responsible for almost 10% of the overall particulate matter released during the 2015 fire event, highlighting the importance of this fire type to overall emission totals. Discriminating these different fires types in ways demonstrated herein should thus ultimately improve the accuracy of SE Asian fire emissions estimates derived using the FRP approach, and the air quality modelling which they support.

16.
Br J Cancer ; 120(3): 356-367, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30655616

RESUMEN

BACKGROUND: Metabolic changes in tumour cells are used in clinical imaging and may provide potential therapeutic targets. Human papillomavirus (HPV) status is important in classifying head and neck cancers (HNSCC), identifying a distinct clinical phenotype; metabolic differences between these HNSCC subtypes remain poorly understood. METHODS: We used RNA sequencing to classify the metabolic expression profiles of HPV+ve and HPV-ve HNSCC, performed a meta-analysis on FDG-PET imaging characteristics and correlated results with in vitro extracellular flux analysis of HPV-ve and HPV+ve HNSCC cell lines. The monocarboxylic acid transporter-1 (MCT1) was identified as a potential metabolic target and tested in functional assays. RESULTS: Specific metabolic profiles were associated with HPV status, not limited to carbohydrate metabolism. There was dominance of all energy pathways in HPV-negative disease, with elevated expression of genes associated with glycolysis and oxidative phosphorylation. In vitro analysis confirmed comparative increased rates of oxidative phosphorylation and glycolysis in HPV-negative cell lines. PET SUV(max) scores however were unable to reliably differentiate between HPV-positive and HPV-negative tumours. MCT1 expression was significantly increased in HPV-negative tumours, and inhibition suppressed tumour cell invasion, colony formation and promoted radiosensitivity. CONCLUSION: HPV-positive and negative HNSCC have different metabolic profiles which may have potential therapeutic applications.


Asunto(s)
Transportadores de Ácidos Monocarboxílicos/genética , Papillomaviridae/patogenicidad , Infecciones por Papillomavirus/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Simportadores/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/genética , Glucólisis/genética , Humanos , Transportadores de Ácidos Monocarboxílicos/aislamiento & purificación , Transportadores de Ácidos Monocarboxílicos/metabolismo , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Fosforilación Oxidativa , Papillomaviridae/genética , Papillomaviridae/metabolismo , Infecciones por Papillomavirus/diagnóstico por imagen , Infecciones por Papillomavirus/patología , Infecciones por Papillomavirus/virología , Tomografía de Emisión de Positrones , Tolerancia a Radiación , Análisis de Secuencia de ARN , Carcinoma de Células Escamosas de Cabeza y Cuello/diagnóstico por imagen , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/virología , Simportadores/aislamiento & purificación , Simportadores/metabolismo
17.
Dermatol Ther ; 32(3): e12800, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30523664

RESUMEN

Cyclooxygenase-2 (COX-2) and its metabolic product prostaglandin E2 (PGE2 ) are induced in response to growth factors, inflammatory cytokines, tumor promoters, activated oncogenes, and, in the skin, ultraviolet (UV) radiation. Accumulating evidence suggests a role for the COX-2/PGE2 pathway in tumorigenesis in various tissue types including cutaneous squamous cell carcinoma. There is also strong evidence for a role in the development of actinic keratoses (AKs) - common dysplastic lesions of the skin associated with UV radiation overexposure - considered as part of a continuum with skin cancer. Non-steroidal anti-inflammatory drugs (NSAIDs) exert their anti-inflammatory, analgesic, and antipyretic effects by reversibly or irreversibly acetylating COX isoforms, inhibiting downstream prostaglandins, and may have a chemopreventive role in malignancies, including skin cancer. Topical treatment of AK lesions with the NSAID diclofenac sodium 3% in combination with hyaluronic acid 2.5% has been shown to be effective and well tolerated, although the mechanism of action remains to be elucidated.


Asunto(s)
Diclofenaco/administración & dosificación , Ácido Hialurónico/administración & dosificación , Queratosis Actínica/tratamiento farmacológico , Administración Cutánea , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/farmacología , Carcinoma de Células Escamosas/prevención & control , Inhibidores de la Ciclooxigenasa 2/administración & dosificación , Inhibidores de la Ciclooxigenasa 2/farmacología , Diclofenaco/farmacología , Humanos , Queratosis Actínica/patología , Neoplasias Cutáneas/prevención & control
18.
Proc Natl Acad Sci U S A ; 113(3): 763-8, 2016 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-26719418

RESUMEN

Dual leucine-zipper kinase (DLK) is critical for axon-to-soma retrograde signaling following nerve injury. However, it is unknown how DLK, a predicted soluble kinase, conveys long-distance signals and why homologous kinases cannot compensate for loss of DLK. Here, we report that DLK, but not homologous kinases, is palmitoylated at a conserved site adjacent to its kinase domain. Using short-hairpin RNA knockdown/rescue, we find that palmitoylation is critical for DLK-dependent retrograde signaling in sensory axons. This functional importance is because of three novel cellular and molecular roles of palmitoylation, which targets DLK to trafficking vesicles, is required to assemble DLK signaling complexes and, unexpectedly, is essential for DLK's kinase activity. By simultaneously controlling DLK localization, interactions, and activity, palmitoylation ensures that only vesicle-bound DLK is active in neurons. These findings explain how DLK specifically mediates nerve injury responses and reveal a novel cellular mechanism that ensures the specificity of neuronal kinase signaling.


Asunto(s)
Axones/metabolismo , Axones/patología , Proteínas de Caenorhabditis elegans/metabolismo , Lipoilación , Quinasas Quinasa Quinasa PAM/metabolismo , Transducción de Señal , Secuencia de Aminoácidos , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/química , Secuencia Conservada , Evolución Molecular , Colorantes Fluorescentes/metabolismo , Técnicas de Silenciamiento del Gen , Células HEK293 , Humanos , Quinasas Quinasa Quinasa PAM/química , Microfluídica , Modelos Biológicos , Datos de Secuencia Molecular , Mutación , Fosforilación , Unión Proteica , Multimerización de Proteína , Transporte de Proteínas , ARN Interferente Pequeño/metabolismo , Ratas , Células Receptoras Sensoriales/metabolismo , Transfección , Vesículas Transportadoras/metabolismo
19.
Carcinogenesis ; 39(6): 798-807, 2018 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-29506142

RESUMEN

The dissemination of cancer cells to local and distant sites depends on a complex and poorly understood interplay between malignant cells and the cellular and non-cellular components surrounding them, collectively termed the tumour microenvironment. One of the most abundant cell types of the tumour microenvironment is the fibroblast, which becomes corrupted by locally derived cues such as TGF-ß1 and acquires an altered, heterogeneous phenotype (cancer-associated fibroblasts, CAF) supportive of tumour cell invasion and metastasis. Efforts to develop new treatments targeting the tumour mesenchyme are hampered by a poor understanding of the mechanisms underlying the development of CAF. Here, we examine the contribution of microRNA to the development of experimentally-derived CAF and correlate this with changes observed in CAF derived from tumours. Exposure of primary normal human fibroblasts to TGF-ß1 resulted in the acquisition of a myofibroblastic CAF-like phenotype. This was associated with increased expression of miR-145, a miRNA predicted in silico to target multiple components of the TGF-ß signalling pathway. miR-145 was also overexpressed in CAF derived from oral cancers. Overexpression of miR-145 blocked TGF-ß1-induced myofibroblastic differentiation and reverted CAF towards a normal fibroblast phenotype. We conclude that miR-145 is a key regulator of the CAF phenotype, acting in a negative feedback loop to dampen acquisition of myofibroblastic traits, a key feature of CAF associated with poor disease outcome.


Asunto(s)
Fibroblastos Asociados al Cáncer/metabolismo , MicroARNs/metabolismo , Neoplasias de la Boca/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Diferenciación Celular/fisiología , Línea Celular Tumoral , Humanos , Miofibroblastos/metabolismo , Fenotipo , Transducción de Señal/fisiología , Microambiente Tumoral/fisiología
20.
Br J Cancer ; 118(9): 1200-1207, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29593339

RESUMEN

BACKGROUND: Cancer-associated fibroblasts (CAFs) form the major stromal component of the tumour microenvironment (TME). The present study aimed to examine the proteomic profiles of CAFs vs. normal fibroblasts (NOFs) from patients with oesophageal adenocarcinoma to gain insight into their pro-oncogenic phenotype. METHODS: CAFs/NOFs from four patients were sub-cultured and analysed using quantitative proteomics. Differentially expressed proteins (DEPs) were subjected to bioinformatics and compared with published proteomics and transcriptomics  datasets. RESULTS: Principal component analysis of all profiled proteins showed that CAFs had high heterogeneity and clustered separately from NOFs. Bioinformatics interrogation of the DEPs demonstrated inhibition of adhesion of epithelial cells, adhesion of connective tissue cells and cell death of fibroblast cell lines in CAFs vs. NOFs (p < 0.0001). KEGG pathway analysis showed a significant enrichment of the insulin-signalling pathway (p = 0.03). Gene ontology terms related with myofibroblast phenotype, metabolism, cell adhesion/migration, hypoxia/oxidative stress, angiogenesis, immune/inflammatory response were enriched in CAFs vs. NOFs. Nestin, a stem-cell marker up-regulated in CAFs vs. NOFs, was confirmed to be expressed in the TME with immunohistochemistry. CONCLUSIONS: The identified pathways and participating proteins may provide novel insight on the tumour-promoting properties of CAFs and unravel novel adjuvant therapeutic targets in the TME.


Asunto(s)
Adenocarcinoma/metabolismo , Fibroblastos Asociados al Cáncer/metabolismo , Neoplasias Esofágicas/metabolismo , Fibroblastos/metabolismo , Proteoma/análisis , Adenocarcinoma/patología , Fibroblastos Asociados al Cáncer/patología , Células Cultivadas , Conjuntos de Datos como Asunto , Neoplasias Esofágicas/patología , Fibroblastos/patología , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Cultivo Primario de Células , Proteoma/metabolismo , Proteómica/métodos , Transcriptoma , Microambiente Tumoral/fisiología
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