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1.
Sci Adv ; 9(39): eadg1894, 2023 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-37774029

RESUMEN

Intratumoral heterogeneity can wreak havoc on current precision medicine strategies because of challenges in sufficient sampling of geographically separated areas of biodiversity distributed across centimeter-scale tumor distances. To address this gap, we developed a deep learning pipeline that leverages histomorphologic fingerprints of tissue to create "Histomic Atlases of Variation Of Cancers" (HAVOC). Using a number of objective molecular readouts, we demonstrate that HAVOC can define regional cancer boundaries with distinct biology. Using larger tumor specimens, we show that HAVOC can map biodiversity even across multiple tissue sections. By guiding profiling of 19 partitions across six high-grade gliomas, HAVOC revealed that distinct differentiation states can often coexist and be regionally distributed within these tumors. Last, to highlight generalizability, we benchmark HAVOC on additional tumor types. Together, we establish HAVOC as a versatile tool to generate small-scale maps of tissue heterogeneity and guide regional deployment of molecular resources to relevant biodiverse niches.


Asunto(s)
Biodiversidad , Glioma , Humanos , Redes Neurales de la Computación
2.
Pract Lab Med ; 37: e00334, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37711668

RESUMEN

The drug screen test on a 12-year-old male patient was positive for opiates by a kinetic interaction of microparticles in solution (KIMS) immunoassay method on the Roche Cobas C502. The positive opiates result was not confirmed by the liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. A chart review revealed that the patient had tuberculosis and was on rifampin. We spiked rifampin into drug-free urine and tested opiates with the Cobas method. Once again, a positive result was obtained. This case showed that rifampin can still cause false positive opiate results measured with the KIMS method. We want to stress the importance of confirming positive screen results by more specific methods such as LC-MS/MS.

4.
Sci Data ; 9(1): 596, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-36182941

RESUMEN

Glioblastoma is often subdivided into three transcriptional subtypes (classical, proneural, mesenchymal) based on bulk RNA signatures that correlate with distinct genetic and clinical features. Potential cellular-level differences of these subgroups, such as the relative proportions of glioblastoma's hallmark histopathologic features (e.g. brain infiltration, microvascular proliferation), may provide insight into their distinct phenotypes but are, however, not well understood. Here we leverage machine learning and reference proteomic profiles derived from micro-dissected samples of these major histomorphologic glioblastoma features to deconvolute and estimate niche proportions in an independent proteogenomically-characterized cohort. This approach revealed a strong association of the proneural transcriptional subtype with a diffusely infiltrating phenotype. Similarly, enrichment of a microvascular proliferation proteomic signature was seen within the mesenchymal subtype. This study is the first to link differences in the cellular pathology signatures and transcriptional profiles of glioblastoma, providing potential new insights into the genetic drivers and poor treatment response of specific subsets of glioblastomas.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Glioblastoma/genética , Glioblastoma/patología , Humanos , Fenotipo , Proteoma/genética , Proteómica , ARN , Transcriptoma
5.
Ultrasonics ; 126: 106821, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35988512

RESUMEN

In vivo ultrasound imaging with phased array transducers is of great importance for both clinical application and biomedical research. In this work, relaxor ferroelectric PMN-0.28PT single crystal with very high piezoelectric constant d33 ≥ 2000 pC/N and electromechanical coupling coefficient k33 âˆ¼ 0.92 is used to fabricate high-frequency phased array transducers. A 128-element 20-MHz phased array transducer is successfully fabricated, and the optimized performance of -6 dB average bandwidth of âˆ¼ 84 % and insertion loss of -43 dB are achieved. The axial and lateral imaging resolutions of the transducer are determined to be 81 µm and 243 µm, respectively. With Verasonics image platform, in vivo fisheye images are acquired, demonstrating the potential application of our developed high-frequency phased array transducer for biomedical research on small animals.


Asunto(s)
Transductores , Animales , Diseño de Equipo , Ultrasonografía
6.
Proteomics ; 22(23-24): e2200127, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35971647

RESUMEN

The human brain represents one of the most complex biological structures with significant spatiotemporal molecular plasticity occurring through early development, learning, aging, and disease. While much progress has been made in mapping its transcriptional architecture, more downstream phenotypic readouts are relatively scarce due to limitations with tissue heterogeneity and accessibility, as well as an inability to amplify protein species prior to global -OMICS analysis. To address some of these barriers, our group has recently focused on using mass-spectrometry workflows compatible with small amounts of formalin-fixed paraffin-embedded tissue samples. This has enabled exploration into spatiotemporal proteomic signatures of the brain and disease across otherwise inaccessible neurodevelopmental timepoints and anatomical niches. Given the similar theme and approaches, we introduce an integrated online portal, "The Brain Protein Atlas (BPA)" (www.brainproteinatlas.org), representing a public resource that allows users to access and explore these amalgamated datasets. Specifically, this portal contains a growing set of peer-reviewed mass-spectrometry-based proteomic datasets, including spatiotemporal profiles of human cerebral development, diffuse gliomas, clinically aggressive meningiomas, and a detailed anatomic atlas of glioblastoma. One barrier to entry in mass spectrometry-based proteomics data analysis is the steep learning curve required to extract biologically relevant data. BPA, therefore, includes several built-in analytical tools to generate relevant plots (e.g., volcano plots, heatmaps, boxplots, and scatter plots) and evaluate the spatiotemporal patterns of proteins of interest. Future iterations aim to expand available datasets, including those generated by the community at large, and analytical tools for exploration. Ultimately, BPA aims to improve knowledge dissemination of proteomic information across the neuroscience community in hopes of accelerating the biological understanding of the brain and various maladies.


Asunto(s)
Glioblastoma , Proteómica , Humanos , Proteómica/métodos , Proteínas , Espectrometría de Masas , Encéfalo
7.
Cell Rep ; 39(8): 110846, 2022 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-35613588

RESUMEN

Cerebral organoids have emerged as robust models for neurodevelopmental and pathological processes, as well as a powerful discovery platform for less-characterized neurobiological programs. Toward this prospect, we leverage mass-spectrometry-based proteomics to molecularly profile precursor and neuronal compartments of both human-derived organoids and mid-gestation fetal brain tissue to define overlapping programs. Our analysis includes recovery of precursor-enriched transcriptional regulatory proteins not found to be differentially expressed in previous transcriptomic datasets. To highlight the discovery potential of this resource, we show that RUVBL2 is preferentially expressed in the SOX2-positive compartment of organoids and that chemical inactivation leads to precursor cell displacement and apoptosis. To explore clinicopathological correlates of this cytoarchitectural disruption, we interrogate clinical datasets and identify rare de novo genetic variants involving RUVBL2 in patients with neurodevelopmental impairments. Together, our findings demonstrate how cell-type-specific profiling of organoids can help nominate previously unappreciated genes in neurodevelopment and disease.


Asunto(s)
Organoides , Proteómica , ATPasas Asociadas con Actividades Celulares Diversas/metabolismo , Encéfalo/metabolismo , Proteínas Portadoras/metabolismo , ADN Helicasas/metabolismo , Humanos , Neuronas/metabolismo , Organoides/metabolismo , Proteómica/métodos , Transcriptoma/genética
8.
Nat Commun ; 13(1): 116, 2022 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-35013227

RESUMEN

Glioblastoma is an aggressive form of brain cancer with well-established patterns of intra-tumoral heterogeneity implicated in treatment resistance and progression. While regional and single cell transcriptomic variations of glioblastoma have been recently resolved, downstream phenotype-level proteomic programs have yet to be assigned across glioblastoma's hallmark histomorphologic niches. Here, we leverage mass spectrometry to spatially align abundance levels of 4,794 proteins to distinct histologic patterns across 20 patients and propose diverse molecular programs operational within these regional tumor compartments. Using machine learning, we overlay concordant transcriptional information, and define two distinct proteogenomic programs, MYC- and KRAS-axis hereon, that cooperate with hypoxia to produce a tri-dimensional model of intra-tumoral heterogeneity. Moreover, we highlight differential drug sensitivities and relative chemoresistance in glioblastoma cell lines with enhanced KRAS programs. Importantly, these pharmacological differences are less pronounced in transcriptional glioblastoma subgroups suggesting that this model may provide insights for targeting heterogeneity and overcoming therapy resistance.


Asunto(s)
Neoplasias Encefálicas/genética , Heterogeneidad Genética , Glioblastoma/genética , Hipoxia/genética , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/mortalidad , Línea Celular Tumoral , Estudios de Cohortes , Progresión de la Enfermedad , Resistencia a Antineoplásicos/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Glioblastoma/diagnóstico , Glioblastoma/tratamiento farmacológico , Glioblastoma/mortalidad , Humanos , Hipoxia/diagnóstico , Hipoxia/tratamiento farmacológico , Hipoxia/mortalidad , Captura por Microdisección con Láser , Aprendizaje Automático , Modelos Genéticos , Proteínas de Neoplasias/clasificación , Proteínas de Neoplasias/metabolismo , Proteómica/métodos , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Análisis de Supervivencia , Transcriptoma
9.
Drug Chem Toxicol ; 45(2): 834-838, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32538189

RESUMEN

There are an estimated 1 billion cases of superficial fungal infection globally. Fungal pathogens form biofilms within wounds and delay the wound healing process. Miconazole and terbinafine are commonly used to treat fungal infections. They induce the accumulation of reactive oxygen species (ROS) in fungi, resulting in the death of fungal cells. ROS are highly reactive molecules, such as oxygen (O2), superoxide anion (O2•-), hydrogen peroxide (H2O2) and hydroxyl radicals (•OH). Although ROS generation is useful for killing pathogenic fungi, it is cytotoxic to human keratinocytes. To the best of our knowledge, the effect of miconazole and terbinafine on HaCaT cells has not been studied with respect to intracellular ROS stimulation. We hypothesized that miconazole and terbinafine have anti-wound healing effects on skin cells when used in antifungal treatment because they generate ROS in fungal cells. We used sulforhodamine B protein staining to investigate cytotoxicity and 2',7'-dichlorofluorescein diacetate to determine ROS accumulation at the 50% inhibitory concentrations of miconazole and terbinafine in HaCaT cells. Our preliminary results showed that topical treatment with miconazole and terbinafine induced cytotoxic responses, with miconazole showing higher cytotoxicity than terbinafine. Both the treatments stimulated ROS in keratinocytes, which may induce oxidative stress and cell death. This suggests a negative correlation between intracellular ROS accumulation in keratinocytes treated with miconazole or terbinafine and the healing of fungi-infected skin wounds.


Asunto(s)
Peróxido de Hidrógeno , Miconazol , Humanos , Peróxido de Hidrógeno/farmacología , Queratinocitos , Miconazol/metabolismo , Miconazol/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Terbinafina/metabolismo , Terbinafina/toxicidad
10.
Mult Scler ; 28(2): 300-308, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34037472

RESUMEN

BACKGROUND: Early detection and monitoring of cognitive dysfunction in multiple sclerosis (MS) may be enabled with smartphone-adapted tests that allow frequent measurements in the everyday environment. OBJECTIVES: The aim of this study was to determine the reliability, construct and concurrent validity of a smartphone-adapted Symbol Digit Modalities Test (sSDMT). METHODS: During a 28-day follow-up, 102 patients with MS and 24 healthy controls (HC) used the MS sherpa® app to perform the sSDMT every 3 days on their own smartphone. Patients performed the Brief International Cognitive Assessment for MS at baseline. Test-retest reliability (intraclass correlation coefficients, ICC), construct validity (group analyses between cognitively impaired (CI), cognitively preserved (CP) and HC for differences) and concurrent validity (correlation coefficients) were assessed. RESULTS: Patients with MS and HC completed an average of 23.2 (SD = 10.0) and 18.3 (SD = 10.2) sSDMT, respectively. sSDMT demonstrated high test-retest reliability (ICCs > 0.8) with a smallest detectable change of 7 points. sSDMT scores were different between CI patients, CP patients and HC (all ps < 0.05). sSDMT correlated modestly with the clinical SDMT (highest r = 0.690), verbal (highest r = 0.516) and visuospatial memory (highest r = 0.599). CONCLUSION: Self-administered smartphone-adapted SDMT scores were reliable and different between patients who were CI, CP and HC and demonstrated concurrent validity in assessing information processing speed.


Asunto(s)
Esclerosis Múltiple , Cognición , Humanos , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/psicología , Pruebas Neuropsicológicas , Reproducibilidad de los Resultados , Teléfono Inteligente
11.
Mult Scler ; 27(9): 1421-1431, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33150823

RESUMEN

BACKGROUND: Clinical measures in multiple sclerosis (MS) face limitations that may be overcome by utilising smartphone keyboard interactions acquired continuously and remotely during regular typing. OBJECTIVE: The aim of this study was to determine the reliability and validity of keystroke dynamics to assess clinical aspects of MS. METHODS: In total, 102 MS patients and 24 controls were included in this observational study. Keyboard interactions were obtained with the Neurokeys keyboard app. Eight timing-related keystroke features were assessed for reliability with intraclass correlation coefficients (ICCs); construct validity by analysing group differences (in fatigue, gadolinium-enhancing lesions on magnetic resonance imaging (MRI), and patients vs controls); and concurrent validity by correlating with disability measures. RESULTS: Reliability was moderate in two (ICC = 0.601 and 0.742) and good to excellent in the remaining six features (ICC = 0.760-0.965). Patients had significantly higher keystroke latencies than controls. Latency between key presses correlated the highest with Expanded Disability Status Scale (r = 0.407) and latency between key releases with Nine-Hole Peg Test and Symbol Digit Modalities Test (ρ = 0.503 and r = -0.553, respectively), ps < 0.001. CONCLUSION: Keystroke dynamics were reliable, distinguished patients and controls, and were associated with clinical disability measures. Consequently, keystroke dynamics are a promising valid surrogate marker for clinical disability in MS.


Asunto(s)
Esclerosis Múltiple , Evaluación de la Discapacidad , Fatiga , Humanos , Imagen por Resonancia Magnética , Reproducibilidad de los Resultados
12.
Chaos ; 30(11): 113133, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33261343

RESUMEN

Within data gathered through passive monitoring of patients with Multiple Sclerosis (MS), there is a clear necessity for improved methodological approaches to match the emergence of continuous, objective, measuring technologies. As most gold standards measure infrequently and require clinician presence, fluctuations in the daily progression are not accounted for. Due to the underlying conditions of homogeneity and stationarity (the main tenets of ergodicity) not being met for the majority of the statistical methods employed in the clinical setting, alternative approaches should be investigated. A solution is to use a non-linear time series analysis approach. Here, Early-Warning Signals (EWS) in the form of critical fluctuations in Keystroke Dynamics (KD), collected using participant's smartphones, are investigated as indicators for a clinical change in three groups. These are patients with MS and changes in Magnetic Resonance Imaging (MRI), patients with MS but without changes in MRI, and healthy controls (HCs). Here, we report examples of EWS and changes in KD coinciding with clinically relevant changes in outcome measures in both patients with and without differences in the amount of MRI enhancing lesions. We also report no clinically relevant changes in EWS in the HC population. This study is a first promising step toward using EWS to identify periods of instability as measured by a continuous objective measure as a proxy for outcome measures in the field of MS.


Asunto(s)
Esclerosis Múltiple , Humanos , Imagen por Resonancia Magnética
14.
Anal Chem ; 92(16): 11053-11061, 2020 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-32698568

RESUMEN

Cyclosporins are an invaluable class of drug used to prevent the rejection of transplanted tissue. While the most popular drug in this group is cyclosporin A, several other analogues are available, including some enantiomeric and structurally isomeric forms. Unfortunately, the presence of such isomers can make the detection and identification of these drugs by mass spectrometry (MS) alone quite challenging. Here, we demonstrate the separation and analysis of six cyclosporin analogues using liquid chromatography (LC) and differential mobility spectroscopy (DMS) coupled to MS. Using DMS, we demonstrate the separation of three isomers: CycA and CycH (cyclosporin H), which are enantiomers, and isocyclosporin A (a structural isomer of CycA and CycH). For several of the cyclosporins, we can separate different conformers for each isomeric form. After DMS separation, tandem mass spectrometry (MS/MS) analyses of the separated isomers also distinguish these isomeric forms of cyclosporin. In addition, we have probed differences between each isomer by using gas-phase hydrogen-deuterium exchange (HDX) immediately after DMS separation, which reveals differences in the levels of intramolecular hydrogen bonding between each of the cyclosporins.

15.
Chem Biol Interact ; 320: 109023, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32097615

RESUMEN

Antimicrobial resistance remains a serious problem that results in high mortality and increased healthcare costs globally. One of the major issues is that resistant pathogens decrease the efficacy of conventional antimicrobials. Accordingly, development of novel antimicrobial agents and therapeutic strategies is urgently needed to overcome the challenge of antimicrobial resistance. A potential strategy is to kill pathogenic microorganisms via the formation of reactive oxygen species (ROS). ROS are defined as a number of highly reactive molecules that comprise molecular oxygen (O2), superoxide anion (O2•-), hydrogen peroxide (H2O2) and hydroxyl radicals (•OH). ROS exhibit antimicrobial actions against a broad range of pathogens through the induction of oxidative stress, which is an imbalance between ROS and the ability of the antioxidant defence system to detoxify ROS. ROS-dependent oxidative stress can damage cellular macromolecules, including DNA, lipids and proteins. This article reviews the antimicrobial action of ROS, challenges to ROS hypothesis, work to solidify ROS-mediated antimicrobial lethality hypothesis, recent developments in antimicrobial agents using ROS as an antimicrobial strategy, safety concerns related to ROS, and future directions in ROS research.


Asunto(s)
Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , ADN Bacteriano/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Animales , Humanos , Estrés Oxidativo
16.
Mult Scler Relat Disord ; 38: 101489, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31731213

RESUMEN

BACKGROUND: Fampridine is an effective treatment to improve ambulation for some multiple sclerosis (MS) patients. Remarkable discrepancies exist between responder rates in clinical trials and the proportion of patients continuing treatment in clinical practice. This may be related to clinical phenotypes of MS patients, and the influence of patient reported outcome (PRO) on treatment decision making. OBJECTIVE: To analyse responder rates to fampridine on ambulation and upper extremity function (UEF) and the influence on treatment decision making in different clinical subgroups in a real-world setting. METHODS: MS patients with ambulatory impairment treated with fampridine were included. Patients were subdivided based on disease duration, clinical phenotype, Expanded Disability Status Scale (EDSS), baseline walking speed, and presence of UEF impairment. Ambulatory response was assessed with the Timed 25-Foot Walk (T25FW, responder defined as ≥20% improvement) and with the MS Walking Scale (MSWS, responder defined as ≥8 points improvement) as a PRO. For patients also reporting impaired UEF, the Arm Function in MS Questionnaire (AMSQ, responder defined as ≥15 improvement) was the PRO of choice. Decision on treatment continuation was based on improvement of T25FW, MSWS and the clinicians' overall impression for improvement. RESULTS: In total 344 patients were included of which 75.3% continued treatment. More patients with a relapsing clinical phenotype continued treatment vs patients with a progressive phenotype (83.6 vs 68.6%, p < 0.01). A positive linear trend was found between severity of walking disability, as determined by baseline walking speed, and T25FW response (p < 0.01), while there was an inverse linear association between walking disability and MSWS response (p = 0.03). However, the proportion of patients continuing treatment was similar between subgroups of baseline walking speed. Impaired UEF was reported by 183 (66.5%) patients, of which 64 (39.3%) were AMSQ responders. Patients responding on AMSQ compared to non-responders, were also more frequently MSWS responders (82.8 vs 65.3%, p = 0.02), while response on T25FW was similar, and continued treatment more often (85.9 vs 70.7%, p = 0.04). This suggests an influence of PRO on treatment decision making. CONCLUSION: Responder rates and treatment continuation of fampridine differed between clinical subgroups of MS. PROs influenced treatment decision making of fampridine in clinical practice, particularly in patients with mild ambulatory impairment or those reporting UEF impairment. To some extent, these findings explain discrepancies found between clinical trials and clinical practice, and support the importance of subgroup analyses and incorporation of PROs in clinical trials. For clinical practice, using PROs to assess patients experience in conjunction with performance measures helps in treatment decision making.


Asunto(s)
4-Aminopiridina/farmacología , Toma de Decisiones Clínicas , Esclerosis Múltiple Crónica Progresiva/tratamiento farmacológico , Esclerosis Múltiple Crónica Progresiva/fisiopatología , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/fisiopatología , Medición de Resultados Informados por el Paciente , Bloqueadores de los Canales de Potasio/farmacología , Índice de Severidad de la Enfermedad , 4-Aminopiridina/administración & dosificación , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Limitación de la Movilidad , Fenotipo , Bloqueadores de los Canales de Potasio/administración & dosificación , Extremidad Superior/fisiopatología , Velocidad al Caminar/fisiología
17.
Neth J Med ; 77(10): 370-372, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31880273

RESUMEN

Infectious mononucleosis may mimic lymphoma, both clinically and histopathologically. We present a patient with neurological symptoms and lymphadenopathy, initially diagnosed as Epstein-Barr virus (EBV)-positive angioimmunoblastic T-cell lymphoma (AITL) with cerebrospinal fluid (CSF) localisation based on lymph node pathology and a 30-fold higher EBV load in the CSF compared with serum. However, the patient fully recovered spontaneously and EBV became negative in both CSF and serum, suggestive of a dramatic presentation of EBV meningoencephalitis.


Asunto(s)
Infecciones por Virus de Epstein-Barr/diagnóstico , Meningoencefalitis/diagnóstico , Meningoencefalitis/virología , Líquido Cefalorraquídeo/virología , Diagnóstico Diferencial , Humanos , Linfoma/diagnóstico , Masculino , Persona de Mediana Edad
18.
Mol Cell Proteomics ; 18(10): 2029-2043, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31353322

RESUMEN

Molecular characterization of diffuse gliomas has thus far largely focused on genomic and transcriptomic interrogations. Here, we utilized mass spectrometry and overlay protein-level information onto genomically defined cohorts of diffuse gliomas to improve our downstream molecular understanding of these lethal malignancies. Bulk and macrodissected tissues were utilized to quantitate 5,496 unique proteins over three glioma cohorts subclassified largely based on their IDH and 1p19q codeletion status (IDH wild type (IDHwt), n = 7; IDH mutated (IDHmt), 1p19q non-codeleted, n = 7; IDH mutated, 1p19q-codeleted, n = 10). Clustering analysis highlighted proteome and systems-level pathway differences in gliomas according to IDH and 1p19q-codeletion status, including 287 differentially abundant proteins in macrodissection-enriched tumor specimens. IDHwt tumors were enriched for proteins involved in invasiveness and epithelial to mesenchymal transition (EMT), while IDHmt gliomas had increased abundances of proteins involved in mRNA splicing. Finally, these abundance changes were compared with IDH-matched GBM stem-like cells (GSCs) to better pinpoint protein patterns enriched in putative cellular drivers of gliomas. Using this integrative approach, we outline specific proteins involved in chloride transport (e.g. chloride intracellular channel 1, CLIC1) and EMT (e.g. procollagen-lysine, 2-oxoglutarate 5-dioxygenase 3, PLOD3, and serpin peptidase inhibitor clade H member 1, SERPINH1) that showed concordant IDH-status-dependent abundance differences in both primary tissue and purified GSC cultures. Given the downstream position proteins occupy in driving biology and phenotype, understanding the proteomic patterns operational in distinct glioma subtypes could help propose more specific, personalized, and effective targets for the management of patients with these aggressive malignancies.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Deleción Cromosómica , Glioma/metabolismo , Isocitrato Deshidrogenasa/genética , Células Madre Neoplásicas/metabolismo , Proteómica/métodos , Neoplasias Encefálicas/genética , Cromatografía Liquida , Cromosomas Humanos Par 1/genética , Cromosomas Humanos Par 19/genética , Análisis por Conglomerados , Glioma/genética , Humanos , Mutación , Células Madre Neoplásicas/patología , Mapas de Interacción de Proteínas , Análisis de Secuencia de ARN , Espectrometría de Masas en Tándem , Análisis de Matrices Tisulares , Células Tumorales Cultivadas
19.
20.
Phys Chem Chem Phys ; 20(27): 18688-18698, 2018 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-29956702

RESUMEN

Collision-induced dissociation of isotopically labelled protonated pentaglycine produced two abundant [b5]+ ions, the products of the loss of water from the first and second amide groups, labelled [b5]+I and [b5]+II. IRMPD spectroscopy and DFT calculations show that these two [b5]+ ions feature N1-protonated 3,5-dihydro-4H-imidazol-4-one structures. 15N-Labelling established that some interconversion occurs between these two ions but dissociations are preferred. For both ions, DFT calculations show that the barrier to interconversion is slightly higher than those to dissociation. Dehydration of protonated hexaglycine produced three imidazolone ions. Ions [b6]+I and [b6]+II exhibit analogous CID spectra to those from [b5]+I and [b5]+II; however, the spectrum of the [b6]+III ion was dramatically different, showing losses predominantly of a further water molecule or cleavage of the second amide bond to give the glycyloxazolone (a deprotonated [b2]+ ion, labelled GlyGlyox (114 Da)) from the N-terminus. Protonated polyglycines [Glyn + H]+, where n = 7-9, all readily lose at least one water molecule. The corresponding [bn]+ ions lose either a further water molecule, an oxazolone from the N-terminus or a truncated peptide from the C-terminus. The number of amino acid residues in the latter two eliminated neutral molecules provides insight into the location of the imidazolone in the peptide chain and which oxygen was lost in the initial dehydration reaction. From this analysis, it appears that water loss from the longer protonated polyglycines is predominantly from the central residues.

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