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1.
J Wound Care ; 31(4): 330-338, 2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35404694

RESUMO

This narrative clinical review summarises the key evidence in support for the use of a hydro-responsive wound dressing, HydroTac (HRWD-2, PAUL HARTMANN AG, Germany) to address key aspects associated with the treatment of both acute and hard-to-heal wounds. This review demonstrates how HRWD-2 can be used in general to address the challenges presented by a wide range of wound types and skin injuries. It highlights the ability of HRWD-2 to regulate an optimal moist wound environment that promotes wound progression and healing. Key aspects covered in this review include the dressing's ability to: promote certain phases of the wound healing response (for example, re-epithelialisation) address the concepts and needs for wound progression as set out in the TIME wound management framework provide an optimal hydration level reduce tissue trauma and pain at dressing change.


Assuntos
Bandagens , Lesões dos Tecidos Moles , Humanos , Reepitelização , Fatores de Risco , Cicatrização
2.
Eur J Neurosci ; 54(3): 4768-4780, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34061412

RESUMO

Human hearing loss (HL) is often accompanied by comorbidities like tinnitus, which is affecting up to 15% of the adult population. Rodent animal studies could show that tinnitus may not only be a result of apparent HL due to cochlear hair cell damage but can also be a consequence of synaptopathy at the inner hair cells (IHCs) already induced by moderate sound traumata. Here, we investigate synaptopathy previously shown in mice in our animal model, the Mongolian gerbil, and relate it to behavioral signs of tinnitus. Tinnitus was induced by a mild monaural acoustic trauma leading to monaural noise induced HL in the animals, quantified by auditory brainstem response (ABR) audiometry. Behavioral signs of tinnitus percepts were detected by measurement of prepulse inhibition of the acoustic startle response in a gap-noise paradigm. Fourteen days after trauma, the cochleae of both ears were isolated, and IHC synapses were counted within several spectral regions of the cochlea. Behavioral signs of tinnitus were only found in animals with IHC synaptopathy, independent of type of HL. On the other hand, animals with apparent HL but without behavioral signs of tinnitus showed a reduction in amplitudes of ABR waves I&II but no significant changes in the number of synapses at the IHC. We conclude-in line with the literature-that HL is caused by damage to the IHC or by other reasons but that the development of tinnitus, at least in our animal model, is closely linked to synaptopathy at the IHC.


Assuntos
Perda Auditiva Provocada por Ruído , Zumbido , Animais , Limiar Auditivo , Cóclea , Potenciais Evocados Auditivos do Tronco Encefálico , Gerbillinae , Células Ciliadas Auditivas Internas , Humanos , Camundongos , Reflexo de Sobressalto , Zumbido/etiologia
3.
Phys Chem Chem Phys ; 21(37): 20613-20627, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31528972

RESUMO

Atmospheric aerosol particles with a high viscosity may become inhomogeneously mixed during chemical processing. Models have predicted gradients in condensed phase reactant concentration throughout particles as the result of diffusion and chemical reaction limitations, termed chemical gradients. However, these have never been directly observed for atmospherically relevant particle diameters. We investigated the reaction between ozone and aerosol particles composed of xanthan gum and FeCl2 and observed the in situ chemical reaction that oxidized Fe2+ to Fe3+ using X-ray spectromicroscopy. Iron oxidation state of particles as small as 0.2 µm in diameter were imaged over time with a spatial resolution of tens of nanometers. We found that the loss off Fe2+ accelerated with increasing ozone concentration and relative humidity, RH. Concentric 2-D column integrated profiles of the Fe2+ fraction, α, out of the total iron were derived and demonstrated that particle surfaces became oxidized while particle cores remained unreacted at RH = 0-20%. At higher RH, chemical gradients evolved over time, extended deeper from the particle surface, and Fe2+ became more homogeneously distributed. We used the kinetic multi-layer model for aerosol surface and bulk chemistry (KM-SUB) to simulate ozone reaction constrained with our observations and inferred key parameters as a function of RH including Henry's Law constant for ozone, HO3, and diffusion coefficients for ozone and iron, DO3 and DFe, respectively. We found that HO3 is higher in our xanthan gum/FeCl2 particles than for water and increases when RH decreased from about 80% to dry conditions. This coincided with a decrease in both DO3 and DFe. In order to reproduce observed chemical gradients, our model predicted that ozone could not be present further than a few nanometers from a particle surface indicating near surface reactions were driving changes in iron oxidation state. However, the observed chemical gradients in α observed over hundreds of nanometers must have been the result of iron transport from the particle interior to the surface where ozone oxidation occurred. In the context of our results, we examine the applicability of the reacto-diffusive framework and discuss diffusion limitations for other reactive gas-aerosol systems of atmospheric importance.

5.
Scand J Med Sci Sports ; 28(12): 2617-2624, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30102797

RESUMO

AIMS: Right ventricular (RV) adaptation is a common finding in the athlete's heart. The aim of this study was to establish the extent of RV structural and functional adaptation in elite and academy professional footballers compared to age-matched controls. METHODS AND RESULTS: A total of 100 senior and 100 academy elite footballers and 20 senior and 19 academy age-matched controls were recruited. All participants underwent 2D, Doppler, tissue Doppler, and strain (ε) echocardiography of the right heart. Structural indices were derived and indexed allometrically for individual differences in body surface area. Standard RV function was assessed alongside peak RV ε and strain rate (SR). Senior football players had larger scaled RV structural parameters than academy players for the RV outflow (RVOTplax ) (32.7 ± 4.2 and 29.5 ± 4.0 mm(m2 )0.326 , P < 0.001), the proximal RV outflow (RVOT1 ) (26.6 ± 3.5 and 24.7 ± 3.9 mm(m2 )0.335 , P < 0.001), the basal RV inflow (RVD1 ) (33.1 ± 4.1 and 30.7 ± 3.2 mm(m2 )0.404 , P = 0.020), RV length (RVD3 ) (66.5 ± 6.1 and 62.9 ± 5.1 mm(m2 )0.431 , P < 0.001), and RV diastolic area (RVDarea ) (16.9 ± 2.6 and 15.7 ± 2.6 mm(m2 )0.735 , P < 0.001). Both academy and senior football players demonstrated larger scaled structural RV parameters in comparison with age-matched controls. Systolic SR (SRS) was lower in the senior players compared to academy players in the mid (-1.52 ± 0.49 and -1.41 ± 0.34 L/s, P = 0.019) and apical (-1.97 ± 0.74 and -1.72 ± 0.42 L/s, P = 0.025) wall regions, respectively. CONCLUSION: Right ventricular structural adaptation occurs in both senior and academy football players with senior players having larger RV dimensions. Although senior players have slightly lower peak SRS than academy players, all global ε and SR are within normal ranges.


Assuntos
Ventrículos do Coração/anatomia & histologia , Futebol , Função Ventricular Direita , Adolescente , Adulto , Atletas , Estudos de Casos e Controles , Ecocardiografia , Humanos , Masculino , Adulto Jovem
6.
BMC Biotechnol ; 16: 20, 2016 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-26897180

RESUMO

BACKGROUND: Copper is an essential chemical element for life as it is a part of prosthetic groups of enzymes including super oxide dismutase and cytochrome c oxidase; however, it is also toxic at high concentrations. Here, we present the trade-off of copper availability and growth inhibition of a common host used for copper-dependent protein production, Pichia pastoris. RESULTS: At copper concentrations ranging from 0.1 mM (6.35 mg/L) to 2 mM (127 mg/L), growth rates of 0.25 h(-1) to 0.16 h(-1) were observed with copper uptake of as high as 20 mgcopper/gCDW. The intracellular copper content was estimated by subtracting the copper adsorbed on the cell wall from the total copper concentration in the biomass. Higher copper concentrations led to stronger cell growth retardation and, at 10 mM (635 mg/L) and above, to growth inhibition. To test the determined copper concentration range for optimal recombinant protein production, a laccase gene from Aspergillus clavatus [EMBL: EAW07265.1] was cloned under the control of the constitutive glyceraldehyde-3-phosphate (GAP) dehydrogenase promoter for expression in P. pastoris. Notably, in the presence of copper, laccase expression improved the specific growth rate of P. pastoris. Although copper concentrations of 0.1 mM and 0.2 mM augmented laccase expression 4 times up to 3 U/mL compared to the control (0.75 U/mL), while higher copper concentrations resulted in reduced laccase production. An intracellular copper content between 1 and 2 mgcopper/gCDW was sufficient for increased laccase activity. The physiology of the yeast could be excluded as a reason for the stop of laccase production at moderate copper concentrations as no flux redistribution could be observed by (13)C-metabolic flux analysis. CONCLUSION: Copper and its pivotal role to sustain cellular functions is noteworthy. However, knowledge on its cellular accumulation, availability and distribution for recombinant protein production is limited. This study attempts to address one such challenge, which revealed the fact that intracellular copper accumulation influenced laccase production and should be considered for high protein expression of copper-dependent enzymes when using P. pastoris. The results are discussed in the context of P. pastoris as a general host for copper -dependent enzyme production.


Assuntos
Cobre/metabolismo , Cobre/farmacologia , Proteínas Fúngicas/metabolismo , Pichia/efeitos dos fármacos , Pichia/metabolismo , Proteínas Fúngicas/análise , Proteínas Fúngicas/química , Lacase/análise , Lacase/química , Lacase/metabolismo , Análise do Fluxo Metabólico , Pichia/enzimologia , Pichia/genética , Proteínas Recombinantes/análise , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
7.
FEMS Yeast Res ; 14(7): 1090-100, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25187056

RESUMO

The structure and regulation of biosynthesis pathways in Saccharomyces cerevisiae have been detailed extensively. For other hemiascomycetes, genomic sequences are primarily available, whereas biochemical information on them is scarce. The resulting biochemical networks that are used for research in basic science and biotechnology are often biased by data from S. cerevisiae, assuming that there are often implicitly conserved structures between species. We examined the structure of the amino acid biosynthesis network in nine hemiascomycetes, spanning the phylogenetic clade. Differences in the genetic inventory included the presence and absence of isoenzymes and compartmentation of the pathways. Notably, no two hemiascomycetes had identical genetic inventories. For example, the lack of the mitochondrial αIPMS isoenzyme and presence of only one copy of the BCAA aminotransferase in Pichia pastoris indicate a disparately compartmented leucine biosynthesis pathway. Our findings suggest that αIPMS and BCAA aminotransferase are solely located in the cytosol of P. pastoris, requiring correction of the leucine biosynthesis pathway layout in this species. Our results argue for careful use of information from S. cerevisiae and for joint efforts to fill the knowledge gaps in other species. Such analysis will lead to contributions in biotechnology disciplines, such as protein production and compartment engineering.


Assuntos
Aminoácidos/biossíntese , Vias Biossintéticas/genética , Saccharomycetales/genética , Saccharomycetales/metabolismo , Biologia Computacional , Enzimas/análise
8.
Echo Res Pract ; 11(1): 5, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38383464

RESUMO

Transthoracic echocardiography is an essential and widely available diagnostic tool for assessing individuals reporting cardiovascular symptoms, monitoring those with established cardiac conditions and for preparticipation screening of athletes. While its use is well-defined in hospital and clinic settings, echocardiography is increasingly being utilised in the community, including in the rapidly expanding sub-speciality of sports cardiology. There is, however, a knowledge and practical gap in the challenging area of the assessment of coronary artery anomalies, which is an important cause of sudden cardiac death, often in asymptomatic athletic individuals. To address this, we present a step-by-step guide to facilitate the recognition and assessment of anomalous coronary arteries using transthoracic echocardiography at the bedside; whilst recognising the importance of performing dedicated cross-sectional imaging, specifically coronary computed tomography (CTCA) where clinically indicated on a case-by-case basis. This guide is intended to be useful for echocardiographers and physicians in their routine clinical practice whilst recognising that echocardiography remains a highly skill-dependent technique that relies on expertise at the bedside.

9.
Clin Epigenetics ; 16(1): 13, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38229153

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with poor prognosis. It is marked by extraordinary resistance to conventional therapies including chemotherapy and radiation, as well as to essentially all targeted therapies evaluated so far. More than 90% of PDAC cases harbor an activating KRAS mutation. As the most common KRAS variants in PDAC remain undruggable so far, it seemed promising to inhibit a downstream target in the MAPK pathway such as MEK1/2, but up to now preclinical and clinical evaluation of MEK inhibitors (MEKi) failed due to inherent and acquired resistance mechanisms. To gain insights into molecular changes during the formation of resistance to oncogenic MAPK pathway inhibition, we utilized short-term passaged primary tumor cells from ten PDACs of genetically engineered mice. We followed gain and loss of resistance upon MEKi exposure and withdrawal by longitudinal integrative analysis of whole genome sequencing, whole genome bisulfite sequencing, RNA-sequencing and mass spectrometry data. RESULTS: We found that resistant cell populations under increasing MEKi treatment evolved by the expansion of a single clone but were not a direct consequence of known resistance-conferring mutations. Rather, resistant cells showed adaptive DNA hypermethylation of 209 and hypomethylation of 8 genomic sites, most of which overlap with regulatory elements known to be active in murine PDAC cells. Both DNA methylation changes and MEKi resistance were transient and reversible upon drug withdrawal. Furthermore, MEKi resistance could be reversed by DNA methyltransferase inhibition with remarkable sensitivity exclusively in the resistant cells. CONCLUSION: Overall, the concept of acquired therapy resistance as a result of the expansion of a single cell clone with epigenetic plasticity sheds light on genetic, epigenetic and phenotypic patterns during evolvement of treatment resistance in a tumor with high adaptive capabilities and provides potential for reversion through epigenetic targeting.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Camundongos , Metilação de DNA , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , DNA/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/uso terapêutico , Linhagem Celular Tumoral , Mutação
10.
Cell Death Dis ; 13(6): 529, 2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35668077

RESUMO

Radiotherapy is an important modality in lung cancer treatment. Despite advances in treatment planning and dose delivery, patient benefit is still limited by in-field relapse and metastatic recurrence. Simultaneous application of cisplatinum-based chemotherapy leads to moderately improved outcomes, thus providing proof-of-concept for radiosensitization strategies in lung cancer. In an unbiased functional genetic screen for radiosensitization targets in lung cancer, we identified syntaxin 18, a protein involved in retrograde vesicular transport between the Golgi apparatus and endoplasmic reticulum, as mediator of radioresistance. Downregulation of endogenous syntaxin 18 specifically reduced clonogenic survival of radioresistant and radiosensitive lung cancer cells following X-radiation. Gene expression programs regulating DNA repair, mitotic checkpoints and mitosis were altered in isogenic cells with reduced syntaxin 18 expression. Functionally, this translated into impaired DNA damage-induced cell cycle checkpoints leading to cell death by mitotic catastrophe. Interestingly, downregulation of syntaxin 18 in lung cancer cells also impaired expression of markers of epithelial-mesenchymal-transition, and reduced migration and invasion capacity. These findings suggest that syntaxin 18 is a key player regulating genes responsible for controlling the growth of the primary tumor as well as metastases upon radiotherapy of lung cancer. They provide a promising lead for biologically rational radiosensitization strategies impacting on radiation-induced cell death as well as metastasis.


Assuntos
Neoplasias Pulmonares , Recidiva Local de Neoplasia , Linhagem Celular Tumoral , Dano ao DNA , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/radioterapia , Proteínas Qa-SNARE/genética , Tolerância a Radiação/genética
11.
Sci Rep ; 12(1): 18565, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329181

RESUMO

Cytokine receptor-like factor 3 (CRLF3) is a conserved but largely uncharacterized orphan cytokine receptor of eumetazoan animals. CRLF3-mediated neuroprotection in insects can be stimulated with human erythropoietin. To identify mechanisms of CRLF3-mediated neuroprotection we studied the expression and proapoptotic function of acetylcholinesterase in insect neurons. We exposed primary brain neurons from Tribolium castaneum to apoptogenic stimuli and dsRNA to interfere with acetylcholinesterase gene expression and compared survival and acetylcholinesterase expression in the presence or absence of the CRLF3 ligand erythropoietin. Hypoxia increased apoptotic cell death and expression of both acetylcholinesterase-coding genes ace-1 and ace-2. Both ace genes give rise to single transcripts in normal and apoptogenic conditions. Pharmacological inhibition of acetylcholinesterases and RNAi-mediated knockdown of either ace-1 or ace-2 expression prevented hypoxia-induced apoptosis. Activation of CRLF3 with protective concentrations of erythropoietin prevented the increased expression of acetylcholinesterase with larger impact on ace-1 than on ace-2. In contrast, high concentrations of erythropoietin that cause neuronal death induced ace-1 expression and hence promoted apoptosis. Our study confirms the general proapoptotic function of AChE, assigns a role of both ace-1 and ace-2 in the regulation of apoptotic death and identifies the erythropoietin/CRLF3-mediated prevention of enhanced acetylcholinesterase expression under apoptogenic conditions as neuroprotective mechanism.


Assuntos
Acetilcolinesterase , Eritropoetina , Animais , Humanos , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Eritropoetina/genética , Eritropoetina/farmacologia , Eritropoetina/metabolismo , Neurônios/metabolismo , Receptores da Eritropoetina/genética , Receptores da Eritropoetina/metabolismo , Insetos/metabolismo , Hipóxia/metabolismo , Receptores de Citocinas/metabolismo
12.
Echo Res Pract ; 9(1): 10, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36253815

RESUMO

Transthoracic echocardiography is an essential tool in the diagnosis, assessment, and management of paediatric and adult populations with suspected or confirmed congenital heart disease. Congenital echocardiography is highly operator-dependent, requiring advanced technical acquisition and interpretative skill levels. This document is designed to complement previous congenital echocardiography literature by providing detailed practical echocardiography imaging guidance on sequential segmental analysis, and is intended for implementation predominantly, but not exclusively, within adult congenital heart disease settings. It encompasses the recommended dataset to be performed and is structured in the preferred order for a complete anatomical and functional sequential segmental congenital echocardiogram. It is recommended that this level of study be performed at least once on all patients being assessed by a specialist congenital cardiology service. This document will be supplemented by a series of practical pathology specific congenital echocardiography guidelines. Collectively, these will provide structure and standardisation to image acquisition and reporting, to ensure that all important information is collected and interpreted appropriately.

13.
Thorac Cancer ; 13(15): 2180-2191, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35708207

RESUMO

BACKGROUND: CT scans are used in routine clinical practice for the diagnosis and treatment surveillance of non-small cell lung cancer (NSCLC). However, more sensitive methods are desirable. Liquid biopsy analyses of RNA and DNA can offer more sensitive diagnostic approaches. Cell-free RNA (cfRNA) has been described in several malignancies, but its clinical utility has not previously been explored. METHODS: We evaluated the clinical utility of cfRNA for early detection and surveillance of tumor disease in a proof-of-concept study. Using real-time-droplet digital polymerase chain reaction we characterized a candidate transcript (MORF4L2) in plasma samples from 41 advanced stage, 38 early stage NSCLC and 39 healthy samples. We compared its diagnostic performance with tumor markers and evaluated its utility for disease monitoring. RESULTS: MORF4L2 cfRNA was more abundant in patients than in healthy donors (p < 0.0001). Using the Youden index approach (cutoff value of 537 copies/ml was established) with a sensitivity of 0.73 (95% CI: 0.61-0.82) and a specificity of 0.87 (95% CI: 0.73-0.96). Positive and negative predictive values of 0.92 (95% CI: 0.83-0.95) and 0.59 (95% CI: 0.47-0.83) were achieved. Combination of cfRNA and Cyfra21-1 improved its predictive value from 89.5% to 94.7%. Low baseline MORF4L2 levels were associated with better overall survival (HR:0.25, 95% CI: 0.09-0.7, p = 0.009) and progression-free survival for patients treated with tyrosine kinase inhibitors (p = 0.011) and chemotherapy (p = 0.019). MORF4L2 profile between baseline and follow-up mirrored radiological response and tumor dynamics better than tumor markers. cfRNA transcripts allowed monitoring tumor dynamics in patients without tumor-reported genetic alterations. CONCLUSION: Our data support clinical utility of cfRNA for detection and surveillance of NSCLC. Further studies with larger cohorts are required.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Ácidos Nucleicos Livres , Neoplasias Pulmonares , Antígenos de Neoplasias , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Ácidos Nucleicos Livres/genética , Receptores ErbB/genética , Humanos , Queratina-19 , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Estudo de Prova de Conceito , Fatores de Transcrição/genética
14.
Cancers (Basel) ; 14(7)2022 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-35406475

RESUMO

Minimal disseminated and residual disease (MDD/MRD) analyzed by qualitative PCR for NPM-ALK fusion transcripts are validated prognostic factors in pediatric ALK-positive anaplastic large cell lymphoma (ALCL). Although potentially promising, MDD quantification by quantitative real-time PCR in international trials is technically challenging. Quantification of early MRD might further improve risk stratification. We aimed to assess droplet digital PCR for quantification of minimal disease in an inter-laboratory setting in a large cohort of 208 uniformly treated ALCL patients. Inter-laboratory quality control showed high concordance. Using a previously described cut-off of 30 copies NPM-ALK/104 copies ABL1 (NCN) in bone marrow and peripheral blood, MDD quantification allowed identification of very high-risk patients (5-year PFS% 34 ± 5 for patients with ≥30 NCN compared to 74 ± 6 and 76 ± 5 for patients with negative or <30 NCN, respectively, p < 0.0001). While MRD positivity was confirmed as a prognostic marker for the detection of very high-risk patients in this large study, quantification of MRD fusion transcripts did not improve stratification. PFS% was 80 ± 5 and 73 ± 6 for MDD- and MRD-negative patients, respectively, versus 35 ± 10 and 16 ± 8 for MRD-positive patients with <30 and ≥30 NCN, p < 0.0001. Our results suggest that MDD quantification by dPCR enables improved patient stratification in international clinical studies and patient selection for early clinical trials already at diagnosis.

15.
Transl Oncol ; 15(1): 101279, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34800919

RESUMO

BACKGROUND: Radiology is the current standard for monitoring treatment responses in lung cancer. Limited sensitivity, exposure to ionizing radiations and related sequelae constitute some of its major limitation. Non-invasive and highly sensitive methods for early detection of treatment failures and resistance-associated disease progression would have additional clinical utility. METHODS: We analyzed serially collected plasma and paired tumor samples from lung cancer patients (61 with stage IV, 48 with stages I-III disease) and 61 healthy samples by means of next-generation sequencing, radiological imaging and droplet digital polymerase chain reaction (ddPCR) mutation and methylation assays. RESULTS: A 62% variant concordance between tumor-reported and circulating-free DNA (cfDNA) sequencing was observed between baseline liquid and tissue biopsies in stage IV patients. Interestingly, ctDNA sequencing allowed for the identification of resistance-mediating p.T790M mutations in baseline plasma samples for which no such mutation was observed in the corresponding tissue. Serial circulating tumor DNA (ctDNA) mutation analysis by means of ddPCR revealed a general decrease in ctDNA loads between baseline and first reassessment. Additionally, serial ctDNA analyses only recapitulated computed tomography (CT) -monitored tumor dynamics of some, but not all lesions within the same patient. To complement ctDNA variant analysis we devised a ctDNA methylation assay (methcfDNA) based on methylation-sensitive restriction enzymes. cfDNA methylation showed and area under the curve (AUC) of > 0.90 in early and late stage cases. A decrease in methcfDNA between baseline and first reassessment was reflected by a decrease in CT-derive tumor surface area, irrespective of tumor mutational status. CONCLUSION: Taken together, our data support the use of cfDNA sequencing for unbiased characterization of the molecular tumor architecture, highlights the impact of tumor architectural heterogeneity on ctDNA-based tumor surveillance and the added value of complementary approaches such as cfDNA methylation for early detection and monitoring.

16.
Nat Commun ; 13(1): 3055, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35650266

RESUMO

Melanoma is a highly plastic tumor characterized by dynamic interconversion of different cell identities depending on the biological context. Melanoma cells with high expression of the H3K4 demethylase KDM5B (JARID1B) rest in a slow-cycling, yet reversible persister state. Over time, KDM5Bhigh cells can promote rapid tumor repopulation with equilibrated KDM5B expression heterogeneity. The cellular identity of KDM5Bhigh persister cells has not been studied so far, missing an important cell state-directed treatment opportunity in melanoma. Here, we have established a doxycycline-titratable system for genetic induction of permanent intratumor expression of KDM5B and screened for chemical agents that phenocopy this effect. Transcriptional profiling and cell functional assays confirmed that the dihydropyridine 2-phenoxyethyl 4-(2-fluorophenyl)-2,7,7-trimethyl-5-oxo-1,4,5,6,7,8-hexa-hydro-quinoline-3-carboxylate (termed Cpd1) supports high KDM5B expression and directs melanoma cells towards differentiation along the melanocytic lineage and to cell cycle-arrest. The high KDM5B state additionally prevents cell proliferation through negative regulation of cytokinetic abscission. Moreover, treatment with Cpd1 promoted the expression of the melanocyte-specific tyrosinase gene specifically sensitizing melanoma cells for the tyrosinase-processed antifolate prodrug 3-O-(3,4,5-trimethoxybenzoyl)-(-)-epicatechin (TMECG). In summary, our study provides proof-of-concept for a dual hit strategy in melanoma, in which persister state-directed transitioning limits tumor plasticity and primes melanoma cells towards lineage-specific elimination.


Assuntos
Melanoma , Monofenol Mono-Oxigenase , Linhagem Celular Tumoral , Proliferação de Células/genética , Humanos , Melanócitos/metabolismo , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia
17.
J Cardiovasc Magn Reson ; 13: 78, 2011 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-22152255

RESUMO

BACKGROUND: Three dimensional echo is a relatively new technique which may offer a rapid alternative for the examination of the right heart. However its role in patients with non-standard ventricular size or anatomy is unclear. This study compared volumetric measurements of the right ventricle in 25 patients with adult congenital heart disease using both cardiovascular magnetic resonance (CMR) and three dimensional echocardiography. METHODS: Patients were grouped by diagnosis into those expected to have normal or near-normal RV size (patients with repaired coarctation of the aorta) and patients expected to have moderate or worse RV enlargement (patients with repaired tetralogy of Fallot or transposition of the great arteries). Right ventricular end diastolic volume, end systolic volume and ejection fraction were compared using both methods with CMR regarded as the reference standard RESULTS: Bland-Altman analysis of the 25 patients demonstrated that for both RV EDV and RV ESV, there was a significant and systematic under-estimation of volume by 3D echo compared to CMR. This bias led to a mean underestimation of RV EDV by -34% (95%CI: -91% to + 23%). The degree of underestimation was more marked for RV ESV with a bias of -42% (95%CI: -117% to + 32%). There was also a tendency to overestimate RV EF by 3D echo with a bias of approximately 13% (95% CI -52% to +27%). CONCLUSIONS: Statistically significant and clinically meaningful differences in volumetric measurements were observed between the two techniques. Three dimensional echocardiography does not appear ready for routine clinical use in RV assessment in congenital heart disease patients with more than mild RV dilatation at the current time.


Assuntos
Ecocardiografia Tridimensional , Cardiopatias Congênitas/diagnóstico , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Hipertrofia Ventricular Direita/diagnóstico , Adulto , Dilatação Patológica , Feminino , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/patologia , Humanos , Hipertrofia Ventricular Direita/diagnóstico por imagem , Hipertrofia Ventricular Direita/patologia , Imageamento por Ressonância Magnética , Masculino , Variações Dependentes do Observador , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Adulto Jovem
18.
Cell Rep ; 37(8): 110056, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34818551

RESUMO

Statins are among the most commonly prescribed drugs, and around every fourth person above the age of 40 is on statin medication. Therefore, it is of utmost clinical importance to understand the effect of statins on cancer cell plasticity and its consequences to not only patients with cancer but also patients who are on statins. Here, we find that statins induce a partial epithelial-to-mesenchymal transition (EMT) phenotype in cancer cells of solid tumors. Using a comprehensive STRING network analysis of transcriptome, proteome, and phosphoproteome data combined with multiple mechanistic in vitro and functional in vivo analyses, we demonstrate that statins reduce cellular plasticity by enforcing a mesenchymal-like cell state that increases metastatic seeding ability on one side but reduces the formation of (secondary) tumors on the other due to heterogeneous treatment responses. Taken together, we provide a thorough mechanistic overview of the consequences of statin use for each step of cancer development, progression, and metastasis.


Assuntos
Plasticidade Celular/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Neoplasias/metabolismo , Linhagem Celular Tumoral , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Metástase Neoplásica , Células-Tronco Neoplásicas/patologia
19.
F1000Res ; 10: 33, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34035898

RESUMO

Data analysis often entails a multitude of heterogeneous steps, from the application of various command line tools to the usage of scripting languages like R or Python for the generation of plots and tables. It is widely recognized that data analyses should ideally be conducted in a reproducible way. Reproducibility enables technical validation and regeneration of results on the original or even new data. However, reproducibility alone is by no means sufficient to deliver an analysis that is of lasting impact (i.e., sustainable) for the field, or even just one research group. We postulate that it is equally important to ensure adaptability and transparency. The former describes the ability to modify the analysis to answer extended or slightly different research questions. The latter describes the ability to understand the analysis in order to judge whether it is not only technically, but methodologically valid. Here, we analyze the properties needed for a data analysis to become reproducible, adaptable, and transparent. We show how the popular workflow management system Snakemake can be used to guarantee this, and how it enables an ergonomic, combined, unified representation of all steps involved in data analysis, ranging from raw data processing, to quality control and fine-grained, interactive exploration and plotting of final results.


Assuntos
Análise de Dados , Software , Reprodutibilidade dos Testes , Fluxo de Trabalho
20.
Nat Commun ; 12(1): 5505, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535668

RESUMO

Kinase inhibitors suppress the growth of oncogene driven cancer but also enforce the selection of treatment resistant cells that are thought to promote tumor relapse in patients. Here, we report transcriptomic and functional genomics analyses of cells and tumors within their microenvironment across different genotypes that persist during kinase inhibitor treatment. We uncover a conserved, MAPK/IRF1-mediated inflammatory response in tumors that undergo stemness- and senescence-associated reprogramming. In these tumor cells, activation of the innate immunity sensor RIG-I via its agonist IVT4, triggers an interferon and a pro-apoptotic response that synergize with concomitant kinase inhibition. In humanized lung cancer xenografts and a syngeneic Egfr-driven lung cancer model these effects translate into reduction of exhausted CD8+ T cells and robust tumor shrinkage. Overall, the mechanistic understanding of MAPK/IRF1-mediated intratumoral reprogramming may ultimately prolong the efficacy of targeted drugs in genetically defined cancer patients.


Assuntos
Proteína DEAD-box 58/metabolismo , Imunidade Inata , Inflamação/patologia , Sistema de Sinalização das MAP Quinases , Neoplasias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Receptores Imunológicos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Citocinas/metabolismo , Receptores ErbB/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Evasão da Resposta Imune/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Fator Regulador 1 de Interferon/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/patologia , Oncogenes , Transdução de Sinais/efeitos dos fármacos
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