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1.
Cell ; 173(2): 470-484.e18, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29551267

RESUMO

B cell activation during normal immune responses and oncogenic transformation impose increased metabolic demands on B cells and their ability to retain redox homeostasis. While the serine/threonine-protein phosphatase 2A (PP2A) was identified as a tumor suppressor in multiple types of cancer, our genetic studies revealed an essential role of PP2A in B cell tumors. Thereby, PP2A redirects glucose carbon utilization from glycolysis to the pentose phosphate pathway (PPP) to salvage oxidative stress. This unique vulnerability reflects constitutively low PPP activity in B cells and transcriptional repression of G6PD and other key PPP enzymes by the B cell transcription factors PAX5 and IKZF1. Reflecting B-cell-specific transcriptional PPP-repression, glucose carbon utilization in B cells is heavily skewed in favor of glycolysis resulting in lack of PPP-dependent antioxidant protection. These findings reveal a gatekeeper function of the PPP in a broad range of B cell malignancies that can be efficiently targeted by small molecule inhibition of PP2A and G6PD.


Assuntos
Carbono/metabolismo , Glucose/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Animais , Linfócitos B/citologia , Linfócitos B/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Glicólise , Humanos , Fator de Transcrição Ikaros/genética , Fator de Transcrição Ikaros/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Estresse Oxidativo , Fator de Transcrição PAX5/genética , Fator de Transcrição PAX5/metabolismo , Via de Pentose Fosfato , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteína Fosfatase 2/deficiência , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transcrição Gênica
2.
Nature ; 588(7836): 157-163, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33239784

RESUMO

Janus kinases (JAKs) mediate responses to cytokines, hormones and growth factors in haematopoietic cells1,2. The JAK gene JAK2 is frequently mutated in the ageing haematopoietic system3,4 and in haematopoietic cancers5. JAK2 mutations constitutively activate downstream signalling and are drivers of myeloproliferative neoplasm (MPN). In clinical use, JAK inhibitors have mixed effects on the overall disease burden of JAK2-mutated clones6,7, prompting us to investigate the mechanism underlying disease persistence. Here, by in-depth phosphoproteome profiling, we identify proteins involved in mRNA processing as targets of mutant JAK2. We found that inactivation of YBX1, a post-translationally modified target of JAK2, sensitizes cells that persist despite treatment with JAK inhibitors to apoptosis and results in RNA mis-splicing, enrichment for retained introns and disruption of the transcriptional control of extracellular signal-regulated kinase (ERK) signalling. In combination with pharmacological JAK inhibition, YBX1 inactivation induces apoptosis in JAK2-dependent mouse and primary human cells, causing regression of the malignant clones in vivo, and inducing molecular remission. This identifies and validates a cell-intrinsic mechanism whereby differential protein phosphorylation causes splicing-dependent alterations of JAK2-ERK signalling and the maintenance of JAK2V617F malignant clones. Therapeutic targeting of YBX1-dependent ERK signalling in combination with JAK2 inhibition could thus eradicate cells harbouring mutations in JAK2.


Assuntos
Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Neoplasias/genética , Neoplasias/patologia , Proteína 1 de Ligação a Y-Box/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Células Clonais/metabolismo , Células Clonais/patologia , Feminino , Xenoenxertos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Íntrons/genética , Janus Quinase 2/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Mutação , Transplante de Neoplasias , Neoplasias/tratamento farmacológico , Fosfoproteínas/análise , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteoma/análise , Proteômica , Splicing de RNA/genética , Indução de Remissão , Proteína 1 de Ligação a Y-Box/antagonistas & inibidores , Proteína 1 de Ligação a Y-Box/química
3.
Mol Syst Biol ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907068

RESUMO

Mass spectrometry has revolutionized cell signaling research by vastly simplifying the analysis of many thousands of phosphorylation sites in the human proteome. Defining the cellular response to perturbations is crucial for further illuminating the functionality of the phosphoproteome. Here we describe µPhos ('microPhos'), an accessible phosphoproteomics platform that permits phosphopeptide enrichment from 96-well cell culture and small tissue amounts in <8 h total processing time. By greatly minimizing transfer steps and liquid volumes, we demonstrate increased sensitivity, >90% selectivity, and excellent quantitative reproducibility. Employing highly sensitive trapped ion mobility mass spectrometry, we quantify ~17,000 Class I phosphosites in a human cancer cell line using 20 µg starting material, and confidently localize ~6200 phosphosites from 1 µg. This depth covers key signaling pathways, rendering sample-limited applications and perturbation experiments with hundreds of samples viable. We employ µPhos to study drug- and time-dependent response signatures in a leukemia cell line, and by quantifying 30,000 Class I phosphosites in the mouse brain we reveal distinct spatial kinase activities in subregions of the hippocampal formation.

4.
Magn Reson Med ; 91(4): 1314-1322, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38044723

RESUMO

PURPOSE: To demonstrate J-difference coediting of glutamate using Hadamard encoding and reconstruction of Mescher-Garwood-edited spectroscopy (HERMES). METHODS: Density-matrix simulations of HERMES (TE 80 ms) and 1D J-resolved (TE 31-229 ms) of glutamate (Glu), glutamine (Gln), γ-aminobutyric acid (GABA), and glutathione (GSH) were performed. HERMES comprised four sub-experiments with editing pulses applied as follows: (A) 1.9/4.56 ppm simultaneously (ONGABA /ONGSH ); (B) 1.9 ppm only (ONGABA /OFFGSH ); (C) 4.56 ppm only (OFFGABA /ONGSH ); and (D) 7.5 ppm (OFFGABA /OFFGSH ). Phantom HERMES and 1D J-resolved experiments of Glu were performed. Finally, in vivo HERMES (20-ms editing pulses) and 1D J-resolved (TE 31-229 ms) experiments were performed on 137 participants using 3 T MRI scanners. LCModel was used for quantification. RESULTS: HERMES simulation and phantom experiments show a Glu-edited signal at 2.34 ppm in the Hadamard sum combination A+B+C+D with no overlapping Gln signal. The J-resolved simulations and phantom experiments show substantial TE modulation of the Glu and Gln signals across the TEs, whose average yields a well-resolved Glu signal closely matching the Glu-edited signal from the HERMES sum spectrum. In vivo quantification of Glu show that the two methods are highly correlated (p < 0.001) with a bias of ∼10%, along with similar between-subject coefficients of variation (HERMES/TE-averaged: ∼7.3%/∼6.9%). Other Hadamard combinations produce the expected GABA-edited (A+B-C-D) or GSH-edited (A-B+C-D) signal. CONCLUSION: HERMES simulation and phantom experiments show the separation of Glu from Gln. In vivo HERMES experiments yield Glu (without Gln), GABA, and GSH in a single MRS scan.


Assuntos
Ácido Glutâmico , Imageamento por Ressonância Magnética , Humanos , Espectroscopia de Ressonância Magnética/métodos , Glutamina , Glutationa/química , Ácido gama-Aminobutírico/química
5.
Cerebellum ; 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363498

RESUMO

Cerebellar atrophy is the neuropathological hallmark of most ataxias. Hence, quantifying the volume of the cerebellar grey and white matter is of great interest. In this study, we aim to identify volume differences in the cerebellum between spinocerebellar ataxia type 1 (SCA1), SCA3 and SCA6 as well as multiple system atrophy of cerebellar type (MSA-C). Our cross-sectional data set comprised mutation carriers of SCA1 (N=12), SCA3 (N=62), SCA6 (N=14), as well as MSA-C patients (N=16). Cerebellar volumes were obtained from T1-weighted magnetic resonance images. To compare the different atrophy patterns, we performed a z-transformation and plotted the intercept of each patient group's model at the mean of 7 years of ataxia duration as well as at the mean ataxia severity of 14 points in the SARA sum score. In addition, we plotted the extrapolation at ataxia duration of 0 years as well as 0 points in the SARA sum score. Patients with MSA-C demonstrated the most pronounced volume loss, particularly in the cerebellar white matter, at the late time intercept. Patients with SCA6 showed a pronounced volume loss in cerebellar grey matter with increasing ataxia severity compared to all other patient groups. MSA-C, SCA1 and SCA3 showed a prominent atrophy of the cerebellar white matter. Our results (i) confirmed SCA6 being considered as a pure cerebellar grey matter disease, (ii) emphasise the involvement of cerebellar white matter in the neuropathology of SCA1, SCA3 and MSA-C, and (iii) reflect the rapid clinical progression in MSA-C.

6.
J Neurooncol ; 168(2): 333-343, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38696050

RESUMO

PURPOSE: To benchmark palliative care practices in neurooncology centers across Germany, evaluating the variability in palliative care integration, timing, and involvement in tumor board discussions. This study aims to identify gaps in care and contribute to the discourse on optimal palliative care strategies. METHODS: A survey targeting both German Cancer Society-certified and non-certified university neurooncology centers was conducted to explore palliative care frameworks and practices for neurooncological patients. The survey included questions on palliative care department availability, involvement in tumor boards, timing of palliative care integration, and use of standardized screening tools for assessing palliative burden and psycho-oncological distress. RESULTS: Of 57 centers contacted, 46 responded (81% response rate). Results indicate a dedicated palliative care department in 76.1% of centers, with palliative specialists participating in tumor board discussions at 34.8% of centers. Variability was noted in the initiation of palliative care, with early integration at the diagnosis stage in only 30.4% of centers. The survey highlighted a significant lack of standardized spiritual care assessments and minimal use of advanced care planning. Discrepancies were observed in the documentation and treatment of palliative care symptoms and social complaints, underscoring the need for comprehensive care approaches. CONCLUSION: The study highlights a diverse landscape of palliative care provision within German neurooncology centers, underscoring the need for more standardized practices and early integration of palliative care. It suggests the necessity for standardized protocols and guidelines to enhance palliative care's quality and uniformity, ultimately improving patient-centered care in neurooncology.


Assuntos
Benchmarking , Cuidados Paliativos , Humanos , Cuidados Paliativos/normas , Alemanha , Oncologia/normas , Inquéritos e Questionários , Neoplasias Encefálicas/terapia , Padrões de Prática Médica/normas , Padrões de Prática Médica/estatística & dados numéricos
7.
Nature ; 558(7711): E5, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29849140

RESUMO

In Fig. 3c of this Letter, the the effects of CRISPR-Cas9-mediated deletion of NR3C1, TXNIP and CNR2 in patient-derived B-lineage leukaemia cells were shown. For curves depicting NR3C1 (left graph), data s for TXNIP (middle graph) were inadvertently plotted. This figure has been corrected online, and the original Fig. 3c is shown as Supplementary Information to this Amendment for transparency. The error does not affect the conclusions of the Letter. In addition, Source Data files have been added for the Figs. 1-4 and Extended Data Figs. 1-10 of the original Letter.

8.
J Infect Dis ; 228(11): 1559-1570, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37540098

RESUMO

BACKGROUND: The aim of this study was to determine whether neurometabolite abnormalities indicating neuroinflammation and neuronal injury are detectable in individuals post-coronavirus disease 2019 (COVID-19) with persistent neuropsychiatric symptoms. METHODS: All participants were studied with proton magnetic resonance spectroscopy at 3 T to assess neurometabolite concentrations (point-resolved spectroscopy, relaxation time/echo time = 3000/30 ms) in frontal white matter (FWM) and anterior cingulate cortex-gray matter (ACC-GM). Participants also completed the National Institutes of Health Toolbox cognition and motor batteries and selected modules from the Patient-Reported Outcomes Measurement Information System. RESULTS: Fifty-four participants were evaluated: 29 post-COVID-19 (mean ± SD age, 42.4 ± 12.3 years; approximately 8 months from COVID-19 diagnosis; 19 women) and 25 controls (age, 44.1 ± 12.3 years; 14 women). When compared with controls, the post-COVID-19 group had lower total N-acetyl compounds (tNAA; ACC-GM: -5.0%, P = .015; FWM: -4.4%, P = .13), FWM glutamate + glutamine (-9.5%, P = .001), and ACC-GM myo-inositol (-6.2%, P = .024). Additionally, only hospitalized patients post-COVID-19 showed age-related increases in myo-inositol, choline compounds, and total creatine (interaction P = .029 to <.001). Across all participants, lower FWM tNAA and higher ACC-GM myo-inositol predicted poorer performance on several cognitive measures (P = .001-.009), while lower ACC-GM tNAA predicted lower endurance on the 2-minute walk (P = .005). CONCLUSIONS: In participants post-COVID-19 with persistent neuropsychiatric symptoms, the lower-than-normal tNAA and glutamate + glutamine indicate neuronal injury, while the lower-than-normal myo-inositol reflects glial dysfunction, possibly related to mitochondrial dysfunction and oxidative stress in Post-COVID participants with persistent neuropsychiatric symptoms.


Assuntos
COVID-19 , Glutamina , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Espectroscopia de Prótons por Ressonância Magnética/métodos , Glutamina/metabolismo , Prótons , Teste para COVID-19 , COVID-19/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Inositol/metabolismo , Glutamatos/metabolismo , Ácido Aspártico/metabolismo
9.
Br J Haematol ; 202(2): 308-317, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37139709

RESUMO

Classical myeloproliferative neoplasms (MPNs) are characterized by distinct clinical phenotypes. The discovery of driver mutations in JAK2, CALR and MPL genes provided new insights into their pathogenesis. Next-generation sequencing (NGS) identified additional somatic mutations, most frequently in epigenetic modulator genes. In this study, a cohort of 95 MPN patients was genetically characterized using targeted NGS. Clonal hierarchies of detected mutations were subsequently analysed using colony forming progenitor assays derived from single cells to study mutation acquisition. Further, the hierarchy of mutations within distinct cell lineages was evaluated. NGS revealed mutations in three epigenetic modulator genes (TET2, DNMT3A, ASXL1) as most common co-mutations to the classical driver mutations. JAK2V617F as well as DNMT3A and TET2 mutations were detected as primary events in disease formation and most cases presented with a linear mutation pattern. Mutations appear mostly in the myeloid lineages but can also appear in lymphoid subpopulations. In one case with a double mutant MPL gene, mutations exclusively appeared in the monocyte lineage. Overall, this study confirms the mutational heterogeneity of classical MPNs and highlights the role of JAK2V617F and epigenetic modifier genes as early events in hematologic disease formation.


Assuntos
Transtornos Mieloproliferativos , Neoplasias , Humanos , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Evolução Clonal/genética , Fenótipo , Mutação , Calreticulina/genética
10.
Magn Reson Med ; 90(5): 1932-1948, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37448116

RESUMO

PURPOSE: To improve the image reconstruction for prospective motion correction (PMC) of simultaneous multislice (SMS) EPI of the brain, an update of receiver phase and resampling of coil sensitivities are proposed and evaluated. METHODS: A camera-based system was used to track head motion (3 translations and 3 rotations) and dynamically update the scan position and orientation. We derived the change in receiver phase associated with a shifted field of view (FOV) and applied it in real-time to each k-space line of the EPI readout trains. Second, for the SMS reconstruction, we adapted resampled coil sensitivity profiles reflecting the movement of slices. Single-shot gradient-echo SMS-EPI scans were performed in phantoms and human subjects for validation. RESULTS: Brain SMS-EPI scans in the presence of motion with PMC and no phase correction for scan plane shift showed noticeable artifacts. These artifacts were visually and quantitatively attenuated when corrections were enabled. Correcting misaligned coil sensitivity maps improved the temporal SNR (tSNR) of time series by 24% (p = 0.0007) for scans with large movements (up to ˜35 mm and 30°). Correcting the receiver phase improved the tSNR of a scan with minimal head movement by 50% from 50 to 75 for a United Kingdom biobank protocol. CONCLUSION: Reconstruction-induced motion artifacts in single-shot SMS-EPI scans acquired with PMC can be removed by dynamically adjusting the receiver phase of each line across EPI readout trains and updating coil sensitivity profiles during reconstruction. The method may be a valuable tool for SMS-EPI scans in the presence of subject motion.


Assuntos
Imagem Ecoplanar , Processamento de Imagem Assistida por Computador , Humanos , Imagem Ecoplanar/métodos , Processamento de Imagem Assistida por Computador/métodos , Estudos Prospectivos , Encéfalo/diagnóstico por imagem , Movimentos da Cabeça , Movimento (Física) , Artefatos
11.
J Magn Reson Imaging ; 57(5): 1552-1564, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36165907

RESUMO

BACKGROUND: Cognitive training may partially reverse cognitive deficits in people with HIV (PWH). Previous functional MRI (fMRI) studies demonstrate that working memory training (WMT) alters brain activity during working memory tasks, but its effects on resting brain network organization remain unknown. PURPOSE: To test whether WMT affects PWH brain functional connectivity in resting-state fMRI (rsfMRI). STUDY TYPE: Prospective. POPULATION: A total of 53 PWH (ages 50.7 ± 1.5 years, two women) and 53 HIV-seronegative controls (SN, ages 49.5 ± 1.6 years, six women). FIELD STRENGTH/SEQUENCE: Axial single-shot gradient-echo echo-planar imaging at 3.0 T was performed at baseline (TL1), at 1-month (TL2), and at 6-months (TL3), after WMT. ASSESSMENT: All participants had rsfMRI and clinical assessments (including neuropsychological tests) at TL1 before randomization to Cogmed WMT (adaptive training, n = 58: 28 PWH, 30 SN; nonadaptive training, n = 48: 25 PWH, 23 SN), 25 sessions over 5-8 weeks. All assessments were repeated at TL2 and at TL3. The functional connectivity estimated by independent component analysis (ICA) or graph theory (GT) metrics (eigenvector centrality, etc.) for different link densities (LDs) were compared between PWH and SN groups at TL1 and TL2. STATISTICAL TESTS: Two-way analyses of variance (ANOVA) on GT metrics and two-sample t-tests on FC or GT metrics were performed. Cognitive (eg memory) measures were correlated with eigenvector centrality (eCent) using Pearson's correlations. The significance level was set at P < 0.05 after false discovery rate correction. RESULTS: The ventral default mode network (vDMN) eCent differed between PWH and SN groups at TL1 but not at TL2 (P = 0.28). In PWH, vDMN eCent changes significantly correlated with changes in the memory ability in PWH (r = -0.62 at LD = 50%) and vDMN eCent before training significantly correlated with memory performance changes (r = 0.53 at LD = 50%). DATA CONCLUSION: ICA and GT analyses showed that adaptive WMT normalized graph properties of the vDMN in PWH. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: 1.


Assuntos
Infecções por HIV , Memória de Curto Prazo , Feminino , Humanos , Pessoa de Meia-Idade , Encéfalo , Mapeamento Encefálico/métodos , Treino Cognitivo , Imageamento por Ressonância Magnética/métodos , Estudos Prospectivos , Estudos de Casos e Controles
12.
Ann Hematol ; 102(10): 2741-2752, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37592092

RESUMO

The approved dose of bosutinib in chronic phase CML is 400 mg QD in first-line and 500 mg QD in later-line treatment. However, given that gastrointestinal (GI) toxicity typically occurs early after treatment initiation, physicians often tend to start therapy with lower doses although this has never been tested systematically in prospective trials in the Western world. The Bosutinib Dose Optimization (BODO) Study, a multicenter phase II study, investigated the tolerability and efficacy of a step-in dosing concept of bosutinib (starting at 300 mg QD) in chronic phase CML patients in 2nd or 3rd line who were intolerant and/or refractory to previous TKI treatment. Of 57 patients included until premature closure of the study due to slow recruitment, 34 (60%) reached the targeted dose level of 500 mg QD following the 2-weekly step-in dosing regimen. While the dosing-in concept failed to reduce GI toxicity (grade II-IV, primary study endpoint) to < 40% (overall rate of 60%; 95% CI: 45-74%), bosutinib treatment (mean dosage: 403 mg/day) showed remarkable efficacy with a cumulative major molecular remission (MMR) rate of 79% (95% CI: 66 to 88%) at month 24. Of thirty patients refractory to previous therapy and not in MMR at baseline, 19 (64%) achieved an MMR during treatment. GI toxicity did not significantly impact on patient-reported outcomes (PRO) and led to treatment discontinuation in only one patient. Overall, the results of our trial support the efficacy and safety of bosutinib after failure of second-generation TKI pre-treatment. Trial registration: NCT02577926.


Assuntos
Leucemia Mieloide de Fase Crônica , Humanos , Estudos Prospectivos , Compostos de Anilina/efeitos adversos , Leucemia Mieloide de Fase Crônica/tratamento farmacológico
13.
Pediatr Res ; 94(1): 356-364, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36456690

RESUMO

BACKGROUND: The aim of this study was to determine the extent to which socioeconomic characteristics of the home and neighborhood are associated with racial inequalities in brain outcomes. METHODS: We performed a cross-sectional analysis of the baseline dataset (v.2.0.1) from the Adolescent Brain and Cognitive Development (ABCD) Study. Cognitive performance was assessed using the National Institutes of Health Toolbox (NIH-TB) cognitive battery. Standard socioeconomic indicators of the family and neighborhood were derived from census-related statistics. Cortical morphometric measures included MRI-derived thickness, area, and volume. RESULTS: 9638 children were included. Each NIH-TB cognitive measure was negatively associated with household and neighborhood socioeconomic characteristics. Differences in cognitive scores between Black or Hispanic children and other racial groups were mitigated by higher household income. Most children from lowest-income families or residents in impoverished neighborhoods were Black or Hispanic. These disparities were associated with racial differences in NIH-TB measures and mediated by smaller cortical brain volumes. CONCLUSIONS: Neighborhood socioeconomic characteristics are associated with racial differences in preadolescent brain outcomes and mitigated by greater household income. Household income mediates racial differences more strongly than neighborhood-level socioeconomic indicators in brain outcomes. Highlighting these socioeconomic risks may direct focused policy-based interventions such as allocation of community resources to ensure equitable brain outcomes in children. IMPACT: Neighborhood socioeconomic characteristics are associated with racial differences in preadolescent brain outcomes and mitigated by greater household income. Household income mediates racial differences more strongly than neighborhood-level socioeconomic indicators in brain outcomes. Highlighting these disparities related to socioeconomic risks may direct focused policy-based interventions such as allocation of community resources to ensure equitable brain outcomes in children.


Assuntos
Pobreza , Grupos Raciais , Criança , Adolescente , Humanos , Estudos Transversais , Fatores Socioeconômicos , Características de Residência , Encéfalo/diagnóstico por imagem
14.
Nature ; 542(7642): 479-483, 2017 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-28192788

RESUMO

B-lymphoid transcription factors, such as PAX5 and IKZF1, are critical for early B-cell development, yet lesions of the genes encoding these transcription factors occur in over 80% of cases of pre-B-cell acute lymphoblastic leukaemia (ALL). The importance of these lesions in ALL has, until now, remained unclear. Here, by combining studies using chromatin immunoprecipitation with sequencing and RNA sequencing, we identify a novel B-lymphoid program for transcriptional repression of glucose and energy supply. Our metabolic analyses revealed that PAX5 and IKZF1 enforce a state of chronic energy deprivation, resulting in constitutive activation of the energy-stress sensor AMPK. Dominant-negative mutants of PAX5 and IKZF1, however, relieved this glucose and energy restriction. In a transgenic pre-B ALL mouse model, the heterozygous deletion of Pax5 increased glucose uptake and ATP levels by more than 25-fold. Reconstitution of PAX5 and IKZF1 in samples from patients with pre-B ALL restored a non-permissive state and induced energy crisis and cell death. A CRISPR/Cas9-based screen of PAX5 and IKZF1 transcriptional targets identified the products of NR3C1 (encoding the glucocorticoid receptor), TXNIP (encoding a glucose-feedback sensor) and CNR2 (encoding a cannabinoid receptor) as central effectors of B-lymphoid restriction of glucose and energy supply. Notably, transport-independent lipophilic methyl-conjugates of pyruvate and tricarboxylic acid cycle metabolites bypassed the gatekeeper function of PAX5 and IKZF1 and readily enabled leukaemic transformation. Conversely, pharmacological TXNIP and CNR2 agonists and a small-molecule AMPK inhibitor strongly synergized with glucocorticoids, identifying TXNIP, CNR2 and AMPK as potential therapeutic targets. Furthermore, our results provide a mechanistic explanation for the empirical finding that glucocorticoids are effective in the treatment of B-lymphoid but not myeloid malignancies. Thus, B-lymphoid transcription factors function as metabolic gatekeepers by limiting the amount of cellular ATP to levels that are insufficient for malignant transformation.


Assuntos
Linfócitos B/metabolismo , Metabolismo Energético/genética , Regulação Neoplásica da Expressão Gênica , Glucose/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Fatores de Transcrição/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Animais , Linfócitos B/efeitos dos fármacos , Carcinogênese/genética , Proteínas de Transporte/agonistas , Proteínas de Transporte/metabolismo , Morte Celular , Imunoprecipitação da Cromatina , Ciclo do Ácido Cítrico , Modelos Animais de Doenças , Feminino , Glucocorticoides/farmacologia , Glucocorticoides/uso terapêutico , Humanos , Fator de Transcrição Ikaros/metabolismo , Camundongos , Camundongos Transgênicos , Fator de Transcrição PAX5/deficiência , Fator de Transcrição PAX5/genética , Fator de Transcrição PAX5/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Ácido Pirúvico/metabolismo , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/metabolismo , Receptores de Glucocorticoides/metabolismo , Análise de Sequência de RNA
15.
Support Care Cancer ; 31(7): 445, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37410174

RESUMO

PURPOSE: Patients with hematologic malignancies (HM) receive palliative care (PC) less often and later than patients with solid tumors (ST). Patients' lack of knowledge about PC and negative feelings about PC are barriers to their willingness to use PC. Is there a difference between patients with HM and ST in their knowledge and willingness to use PC? METHODS: Two hundred ten patients (85 HM, 125 ST) from an oncology day clinic at a university hospital participated in this cross-sectional, questionnaire-based survey. RESULTS: Patients with HM and ST had high knowledge and mainly positive feelings about PC. More than half of the patients answered that they would feel reassured by the use of PC, and one-third would feel anxious or hopeless. The majority of patients (58.3%) were willing to use PC. There are no significant differences between patients with HM and ST. In multiple regression analysis, perceived chance of cure and feelings of reassurance and anxiety are associated with willingness to use PC, but not with the HM/ST disease group. More than half (53.9%) of the participants would like the treating physician to choose the timing of a discussion about PC. CONCLUSION: Our study shows a high level of knowledge and relatively positive feelings of patients about PC, with no differences between patients with HM or ST. They expect their treating physician to initiate communication about PC. Communication should include the patient's feelings about PC and their chances of a cure.


Assuntos
Neoplasias Hematológicas , Neoplasias , Humanos , Cuidados Paliativos , Estudos Transversais , Estudos Prospectivos , Neoplasias/complicações , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/complicações , Alemanha , Emoções
16.
Laryngorhinootologie ; 102(8): 601-611, 2023 08.
Artigo em Alemão | MEDLINE | ID: mdl-36603817

RESUMO

OBJECTIVE: This population-based study investigates the impact of HPV association on overall survival (OS) of oral cavity (OSCC) and oropharyngeal squamous cell carcinoma (OPSCC) in Thuringia and the incidence of HPV-positive (HPV+) and HPV-negative (HPV-) tumors. METHODS: A total of 308 patients (83.4% men; mean age 57.6 years) with a primary diagnosis of OSCC (38%) or OPSCC (62%) from 2008 were included in the study. Descriptive statistics were obtained for the variables. According to Ang's risk classification, patients were classified as low risk of death (HPV+, nonsmokers), intermediate risk (HPV+, smokers) and high risk of death (HPV-smokers). Kaplan-Meier analyses and Cox multivariable regression analysis were performed to examine OS. RESULTS: 22.5% of OPSCC was HPV+ (incidence: 1.89/100,000 population; thereof 80.1% smokers). The proportion of OSCC with HPV+ was 8.5% (incidence: 0.44/100,000; thereof 78.6% smokers). The median follow-up was 31 months. HPV+ patients had significantly better 5-year OS than HPV- patients (81% vs. 49%; p < 0.001). In multivariable analysis lower OS were associated with: HPV-patients (hazard ratio (HR) = 3.2; 95% confidence interval (CI) = 1.6-6.4; p = 0.001), high risk of death according to Ang (HR = 2.3; 95% CI = 1.0-5.4; p = 0.049), older age (HR = 1.7; 95% CI = 1.1-2.4; p = 0.01), T3/T4-classification (HR = 2.1; 95% CI = 1.3-3.2; p = 0.001) and the presence of distant metastases (HR = 2.7; 95% CI = 1.6-4.4; p < 0.001). CONCLUSIONS: HPV+ non-smokers were minority in Thuringia. The majority of HPV+ patients had an intermediate risk of death due to cigarette smoking.


Assuntos
Neoplasias de Cabeça e Pescoço , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Neoplasias Orofaríngeas/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Prognóstico
17.
Neuroimage ; 253: 119080, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35276369

RESUMO

The cerebellum is involved in the acquisition and consolidation of learned fear responses. Knowledge about its contribution to extinction learning, however, is sparse. Extinction processes likely involve erasure of memories, but there is ample evidence that at least part of the original memory remains. We asked the question whether memory persists within the cerebellum following extinction training. The renewal effect, that is the reoccurrence of the extinguished fear memory during recall in a context different from the extinction context, constitutes one of the phenomena indicating that memory of extinguished learned fear responses is not fully erased during extinction training. We performed a differential AB-A/B fear conditioning paradigm in a 7-Tesla (7T) MRI system in 31 young and healthy men. On day 1, fear acquisition training was performed in context A and extinction training in context B. On day 2, recall was tested in contexts A and B. As expected, participants learned to predict that the CS+ was followed by an aversive electric shock during fear acquisition training. Skin conductance responses (SCRs) were significantly higher to the CS+ compared to the CS- at the end of acquisition. Differences in SCRs vanished in extinction and reoccurred in the acquisition context during recall indicating renewal. Fitting SCR data, a deep neural network model was trained to predict the correct shock value for a given stimulus and context. Event-related fMRI analysis with model-derived prediction values as parametric modulations showed significant effects on activation of the posterolateral cerebellum (lobules VI and Crus I) during recall. Since the prediction values differ based on stimulus (CS+ and CS-) and context during recall, data provide support that the cerebellum is involved in context-related recall of learned fear associations. Likewise, mean ß values were highest in lobules VI and Crus I bilaterally related to the CS+ in the acquisition context during early recall. A similar pattern was seen in the vermis, but only on a trend level. Thus, part of the original memory likely remains within the cerebellum following extinction training. We found cerebellar activations related to the CS+ and CS- during fear acquisition training which likely reflect associative and non-associative aspects of the task. Cerebellar activations, however, were not significantly different for CS+ and CS-. Since the CS- was never followed by an electric shock, the cerebellum may contribute to associative learning related to the CS, for example as a safety cue.


Assuntos
Extinção Psicológica , Medo , Mapeamento Encefálico , Cerebelo/diagnóstico por imagem , Cerebelo/fisiologia , Extinção Psicológica/fisiologia , Medo/fisiologia , Resposta Galvânica da Pele , Humanos , Imageamento por Ressonância Magnética , Masculino
18.
Neuroimage ; 264: 119703, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36349595

RESUMO

Quantifying the volume of the cerebellum and its lobes is of profound interest in various neurodegenerative and acquired diseases. Especially for the most common spinocerebellar ataxias (SCA), for which the first antisense oligonculeotide-base gene silencing trial has recently started, there is an urgent need for quantitative, sensitive imaging markers at pre-symptomatic stages for stratification and treatment assessment. This work introduces CerebNet, a fully automated, extensively validated, deep learning method for the lobular segmentation of the cerebellum, including the separation of gray and white matter. For training, validation, and testing, T1-weighted images from 30 participants were manually annotated into cerebellar lobules and vermal sub-segments, as well as cerebellar white matter. CerebNet combines FastSurferCNN, a UNet-based 2.5D segmentation network, with extensive data augmentation, e.g. realistic non-linear deformations to increase the anatomical variety, eliminating additional preprocessing steps, such as spatial normalization or bias field correction. CerebNet demonstrates a high accuracy (on average 0.87 Dice and 1.742mm Robust Hausdorff Distance across all structures) outperforming state-of-the-art approaches. Furthermore, it shows high test-retest reliability (average ICC >0.97 on OASIS and Kirby) as well as high sensitivity to disease effects, including the pre-ataxic stage of spinocerebellar ataxia type 3 (SCA3). CerebNet is compatible with FreeSurfer and FastSurfer and can analyze a 3D volume within seconds on a consumer GPU in an end-to-end fashion, thus providing an efficient and validated solution for assessing cerebellum sub-structure volumes. We make CerebNet available as source-code (https://github.com/Deep-MI/FastSurfer).


Assuntos
Aprendizado Profundo , Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Reprodutibilidade dos Testes , Cerebelo/diagnóstico por imagem
19.
Br J Haematol ; 198(3): 482-491, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35362552

RESUMO

The prognosis of patients with relapsed diffuse large B-cell lymphoma (DLBCL) remains poor with current options. Here we prospectively evaluated the combination of pixantrone with obinutuzumab for up to six cycles for patients with relapsed or refractory DLBCL. Overall response rate (ORR) was the primary end-point. Sixty-eight patients were evaluated, median age was 75 years, median number of prior lines was three (range 1-10), 52 patients (76.5%) were diagnosed with DLBCL and 16 (23.5%) patients had transformed indolent lymphoma or follicular lymphoma (FL) IIIB. ORR was 35.3% for all and 40% for evaluable patients (16.6% complete response), median progression-free survival (PFS) and overall survival (OS) were 2.8 months and 8 months, respectively. Analysis of the cell of origin revealed a superior course for patients with non-GCB (germinal centre B-cell-like) phenotype [median OS not reached (n.r.) vs 5.2 months]. Patients with one prior line had an improved outcome over patients treated in later lines (PFS n.r. vs 2.5 months). Disease progression was the main reason for premature termination. Adverse events were mainly haematologic. The combination treatment revealed no unexpected adverse events. Most relevant non-haematologic toxicity was infection in 28% of patients. In summary, pixantrone-obinutuzumab showed clinical activity with sometimes long-term remission; however, the trial failed to meet its primary end-point.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma Difuso de Grandes Células B , Recidiva Local de Neoplasia , Idoso , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Humanos , Isoquinolinas/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Estudos Prospectivos , Resultado do Tratamento
20.
Hum Brain Mapp ; 43(5): 1611-1629, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34894171

RESUMO

Cerebellar degeneration progressively impairs motor function. Recent research showed that cerebellar patients can improve motor performance with practice, but the optimal feedback type (visual, proprioceptive, verbal) for such learning and the underlying neuroplastic changes are unknown. Here, patients with cerebellar degeneration (N = 40) and age- and sex-matched healthy controls (N = 40) practiced single-joint, goal-directed forearm movements for 5 days. Cerebellar patients improved performance during visuomotor practice, but a training focusing on either proprioceptive feedback, or explicit verbal feedback and instruction did not show additional benefits. Voxel-based morphometry revealed that after training gray matter volume (GMV) was increased prominently in the visual association cortices of controls, whereas cerebellar patients exhibited GMV increase predominantly in premotor cortex. The premotor cortex as a recipient of cerebellar efferents appears to be an important hub in compensatory remodeling following damage of the cerebro-cerebellar motor system.


Assuntos
Imageamento por Ressonância Magnética , Doenças Neurodegenerativas , Encéfalo/diagnóstico por imagem , Cerebelo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Humanos
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