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1.
J Clin Invest ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38885332

RESUMEN

Most children with medulloblastoma (MB) achieve remission, but some face very aggressive metastatic tumors. Their dismal outcome highlights the critical need to advance therapeutic approaches that benefit such high-risk patients. Minnelide, a clinically relevant analog of the natural product triptolide, has oncostatic activity in both preclinical and early clinical settings. Despite its efficacy and tolerable toxicity, this compound has not been evaluated in MB. Utilizing a bioinformatic dataset that integrates cellular drug response data with gene expression, we predicted that Group 3 (G3) MB, which has a poor five-year survival, would be sensitive to triptolide/Minnelide. We subsequently showed that both triptolide and Minnelide attenuate the viability of G3 MB cells ex vivo. Transcriptomic analyses identified MYC signaling, a pathologically relevant driver of G3 MB, as a downstream target of this class of drugs. We validated this MYC dependency in G3 MB cells and showed that triptolide exerts its efficacy by reducing both MYC transcription and MYC protein stability. Importantly, Minnelide acted on MYC to reduce tumor growth and leptomeningeal spread, which resulted in improved survival of G3 MB animal models. Moreover, Minnelide improved the efficacy of adjuvant chemotherapy, further highlighting its potential for the treatment of MYC-driven G3 MB patients.

2.
Can J Neurol Sci ; : 1-6, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38699814

RESUMEN

BACKGROUND: Bilingualism's impact on cognitive assessment remains underexplored. This study analyzes the efficacy of the Mini-Mental State Examination (MMSE) as a screening tool for bilinguals, specifically examining the influence of language choice on balanced and unbalanced Lebanese bilinguals (Arabic-French) and its implications for diagnosing cognitive impairment. METHODS: Ninety-three bilingual healthy controls (mean age = 67.99 ± 9.3) and 29 Alzheimer's disease patients (mean age = 77.2 ± 5.9), including 26 with mild and 3 with moderate dementia, underwent MMSE assessments in both Arabic and French. The study aimed to assess language impact on cognitive screening outcomes in different bilingual subtypes. RESULTS: Sensitivity in screening for cognitive impairment using the MMSE varied based on language and bilingualism subtype. For unbalanced bilinguals, using the prominent language increased sensitivity. Conversely, in balanced bilinguals, employing the societal majority language enhanced sensitivity. This suggests that the conventional use of the non-prominent language in cognitive screening for foreigners/immigrants may result in a subtle loss of MMSE sensitivity. CONCLUSION: This study emphasizes the critical role of language choice in cognitive assessment for bilinguals. The MMSE's sensitivity is influenced by language selection, with clinical implications for screening procedures. Recommendations include using the prominent language for cognitive screening in dominant bilinguals and the societal majority language for balanced bilinguals. This nuanced approach aims to improve the accuracy and cultural sensitivity of cognitive screening in bilingual populations, addressing the gap in current assessment practices.

3.
bioRxiv ; 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38798351

RESUMEN

Background: Medulloblastoma (MB) is the most malignant childhood brain cancer. Group 3 MB subtype accounts for about 25% of MB diagnoses and is associated with the most unfavorable outcomes. Herein, we report that more than half of group 3 MB tumors express melanoma antigens (MAGEs), which are potential prognostic and therapeutic markers. MAGEs are tumor antigens, expressed in several types of adult cancers and associated with poorer prognosis and therapy resistance; however, their expression in pediatric cancers is mostly unknown. The aim of this study was to determine whether MAGEs are activated in pediatric MB. Methods: To determine MAGE frequency in pediatric MB, we obtained formalin-fixed paraffin-embedded tissue (FFPE) samples of 34 patients, collected between 2008 - 2015, from the Children's Medical Center Dallas pathology archives and applied our validated reverse transcription quantitative PCR (RT-qPCR) assay to measure the relative expression of 23 MAGE cancer-testis antigen genes. To validate our data, we analyzed several published datasets from pediatric MB patients and patient-derived orthotopic xenografts, totaling 860 patients. We then examined how MAGE expression affects the growth and oncogenic potential of medulloblastoma cells by CRISPR-Cas9- and siRNA-mediated gene depletion. Results: Our RT-qPCR analysis suggested that MAGEs were expressed in group 3/4 medulloblastoma. Further mining of bulk and single-cell RNA-sequencing datasets confirmed that 50-75% of group 3 tumors activate a subset of MAGE genes. Depletion of MAGEAs, B2, and Cs alter MB cell survival, viability, and clonogenic growth due to decreased proliferation and increased apoptosis. Conclusions: These results indicate that targeting MAGEs in medulloblastoma may be a potential therapeutic option for group 3 medulloblastomas. Key Points: Several Type I MAGE CTAs are expressed in >60% of group 3 MBs. Type I MAGEs affect MB cell proliferation and apoptosis. MAGEs are potential biomarkers and therapeutic targets for group 3 MBs. Importance of the Study: This study is the first comprehensive analysis of all Type I MAGE CTAs ( MAGEA , -B , and -C subfamily members) in pediatric MBs. Our results show that more than 60% of group 3 MBs express MAGE genes, which are required for the viability and growth of cells in which they are expressed. Collectively, these data provide novel insights into the antigen landscape of pediatric MBs. The activation of MAGE genes in group 3 MBs presents potential stratifying and therapeutic options.

4.
Eur J Neurosci ; 59(11): 3074-3092, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38578844

RESUMEN

Focal structural damage to white matter tracts can result in functional deficits in stroke patients. Traditional voxel-based lesion-symptom mapping is commonly used to localize brain structures linked to neurological deficits. Emerging evidence suggests that the impact of structural focal damage may extend beyond immediate lesion sites. In this study, we present a disconnectome mapping approach based on support vector regression (SVR) to identify brain structures and white matter pathways associated with functional deficits in stroke patients. For clinical validation, we utilized imaging data from 340 stroke patients exhibiting motor deficits. A disconnectome map was initially derived from lesions for each patient. Bootstrap sampling was then employed to balance the sample size between a minority group of patients exhibiting right or left motor deficits and those without deficits. Subsequently, SVR analysis was used to identify voxels associated with motor deficits (p < .005). Our disconnectome-based analysis significantly outperformed alternative lesion-symptom approaches in identifying major white matter pathways within the corticospinal tracts associated with upper-lower limb motor deficits. Bootstrapping significantly increased the sensitivity (80%-87%) for identifying patients with motor deficits, with a minimum lesion size of 32 and 235 mm3 for the right and left motor deficit, respectively. Overall, the lesion-based methods achieved lower sensitivities compared with those based on disconnection maps. The primary contribution of our approach lies in introducing a bootstrapped disconnectome-based mapping approach to identify lesion-derived white matter disconnections associated with functional deficits, particularly efficient in handling imbalanced data.


Asunto(s)
Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/fisiopatología , Femenino , Masculino , Persona de Mediana Edad , Anciano , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Adulto , Mapeo Encefálico/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Encéfalo/fisiopatología , Imagen por Resonancia Magnética/métodos , Tractos Piramidales/diagnóstico por imagen , Tractos Piramidales/patología
5.
Nat Commun ; 15(1): 3483, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664416

RESUMEN

Chemical discovery efforts commonly target individual protein domains. Many proteins, including the EP300/CBP histone acetyltransferases (HATs), contain several targetable domains. EP300/CBP are critical gene-regulatory targets in cancer, with existing high potency inhibitors of either the catalytic HAT domain or protein-binding bromodomain (BRD). A domain-specific inhibitory approach to multidomain-containing proteins may identify exceptional-responding tumor types, thereby expanding a therapeutic index. Here, we discover that targeting EP300/CBP using the domain-specific inhibitors, A485 (HAT) or CCS1477 (BRD) have different effects in select tumor types. Group 3 medulloblastoma (G3MB) cells are especially sensitive to BRD, compared with HAT inhibition. Structurally, these effects are mediated by the difluorophenyl group in the catalytic core of CCS1477. Mechanistically, bromodomain inhibition causes rapid disruption of genetic dependency networks that are required for G3MB growth. These studies provide a domain-specific structural foundation for drug discovery efforts targeting EP300/CBP and identify a selective role for the EP300/CBP bromodomain in maintaining genetic dependency networks in G3MB.


Asunto(s)
Proteína p300 Asociada a E1A , Redes Reguladoras de Genes , Meduloblastoma , Humanos , Meduloblastoma/genética , Meduloblastoma/tratamiento farmacológico , Meduloblastoma/metabolismo , Meduloblastoma/patología , Proteína p300 Asociada a E1A/metabolismo , Proteína p300 Asociada a E1A/genética , Proteína p300 Asociada a E1A/antagonistas & inhibidores , Línea Celular Tumoral , Redes Reguladoras de Genes/efectos de los fármacos , Animales , Dominios Proteicos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ratones , Neoplasias Cerebelosas/genética , Neoplasias Cerebelosas/tratamiento farmacológico , Neoplasias Cerebelosas/metabolismo , Neoplasias Cerebelosas/patología , Antineoplásicos/farmacología
6.
Aging Brain ; 5: 100105, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38273866

RESUMEN

We investigated age-related trends in the topology and hierarchical organization of brain structural and functional networks using diffusion-weighted imaging and resting-state fMRI data from a large cohort of healthy aging adults. At the cross-modal level, we explored age-related patterns in the RC involvement of different functional subsystems using a high-resolution functional parcellation. We further assessed age-related differences in the structure-function coupling as well as the network vulnerability to damage to rich club connectivity. Regardless of age, the structural and functional brain networks exhibited a rich club organization and small-world topology. In older individuals, we observed reduced integration and segregation within the frontal-occipital regions and the cerebellum along the brain's medial axis. Additionally, functional brain networks displayed decreased integration and increased segregation in the prefrontal, centrotemporal, and occipital regions, and the cerebellum. In older subjects, structural networks also exhibited decreased within-network and increased between-network RC connectivity. Furthermore, both within-network and between-network RC connectivity decreased in functional networks with age. An age-related decline in structure-function coupling was observed within sensory-motor, cognitive, and subcortical networks. The structural network exhibited greater vulnerability to damage to RC connectivity within the language-auditory, visual, and subcortical networks. Similarly, for functional networks, increased vulnerability was observed with damage to RC connectivity in the cerebellum, language-auditory, and sensory-motor networks. Overall, the network vulnerability decreased significantly in subjects older than 70 in both networks. Our findings underscore significant age-related differences in both brain functional and structural RC connectivity, with distinct patterns observed across the adult lifespan.

7.
J Neurol ; 271(1): 504-518, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37777991

RESUMEN

While neurodegenerative and vascular neurocognitive disorder (NCD) often co-occur, the contribution of vascular lesions, especially stroke lesions identified on MRI, to global cognition in a real-life memory clinic population remains unclear. The main objective of this retrospective study was to determine NCD neuroimaging correlates: the GM atrophy pattern and vascular lesions (especially stroke lesion localization by voxel-based lesion-symptom mapping, VLSM) in a memory clinic. We included 336 patients with mild or major NCD who underwent cerebral MRI and a neuropsychological assessment. The GM atrophy pattern (obtained by voxel-based morphometry, VBM) and the stroke lesion localization (obtained by VLSM) associated with G5 z-score (a global cognitive score), were included as independent variables with other neuroimaging and clinical indices in a stepwise linear regression model. The mean age was 70.3 years and the mean MMSE score 21.3. On MRI, 75 patients had at least one stroke lesion. The G 5 z-score was associated with GM density in the pattern selected by the VBM analysis (R2 variation = 0.166, p < 0.001) and the presence of a stroke lesion in the region selected by the VSLM analysis (mainly in the right frontal region; R2 variation = 0.018, p = 0.008). The interaction between the two factors was insignificant (p = 0.374). In conclusion, in this first study combining VBM and VLSM analysis in a memory clinic, global cognition was associated with a specific GM atrophy pattern and the presence of a stroke lesion mainly in the right frontal region.


Asunto(s)
Disfunción Cognitiva , Accidente Cerebrovascular , Humanos , Anciano , Estudios Retrospectivos , Disfunción Cognitiva/etiología , Disfunción Cognitiva/complicaciones , Neuroimagen , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/patología , Imagen por Resonancia Magnética/métodos , Pruebas Neuropsicológicas , Atrofia/complicaciones
8.
Cancer Res Commun ; 3(12): 2430-2446, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37971169

RESUMEN

Understanding the intricate dynamics between adoptively transferred immune cells and the brain tumor immune microenvironment (TIME) is crucial for the development of effective T cell-based immunotherapies. In this study, we investigated the influence of the TIME and chimeric antigen receptor (CAR) design on the anti-glioma activity of B7-H3-specific CAR T-cells. Using an immunocompetent glioma model, we evaluated a panel of seven fully murine B7-H3 CARs with variations in transmembrane, costimulatory, and activation domains. We then investigated changes in the TIME following CAR T-cell therapy using high-dimensional flow cytometry and single-cell RNA sequencing. Our results show that five out of six B7-H3 CARs with single costimulatory domains demonstrated robust functionality in vitro. However, these CARs had significantly varied levels of antitumor activity in vivo. To enhance therapeutic effectiveness and persistence, we incorporated 41BB and CD28 costimulation through transgenic expression of 41BBL on CD28-based CAR T-cells. This CAR design was associated with significantly improved anti-glioma efficacy in vitro but did not result in similar improvements in vivo. Analysis of the TIME revealed that CAR T-cell therapy influenced the composition of the TIME, with the recruitment and activation of distinct macrophage and endogenous T-cell subsets crucial for successful antitumor responses. Indeed, complete brain macrophage depletion using a CSF1R inhibitor abrogated CAR T-cell antitumor activity. In sum, our study highlights the critical role of CAR design and its modulation of the TIME in mediating the efficacy of adoptive immunotherapy for high-grade glioma. SIGNIFICANCE: CAR T-cell immunotherapies hold great potential for treating brain cancers; however, they are hindered by a challenging immune environment that dampens their effectiveness. In this study, we show that the CAR design influences the makeup of the immune environment in brain tumors, underscoring the need to target specific immune components to improve CAR T-cell performance, and highlighting the significance of using models with functional immune systems to optimize this therapy.


Asunto(s)
Neoplasias Encefálicas , Glioma , Receptores Quiméricos de Antígenos , Ratones , Animales , Receptores Quiméricos de Antígenos/genética , Linfocitos T , Macrófagos Asociados a Tumores/metabolismo , Antígenos CD28/genética , Glioma/terapia , Neoplasias Encefálicas/terapia , Encéfalo/metabolismo , Microambiente Tumoral
9.
Sci Transl Med ; 15(720): eadi1617, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37910601

RESUMEN

The morbidity associated with pediatric medulloblastoma, in particular in patients who develop leptomeningeal metastases, remains high in the absence of effective therapies. Administration of substances directly into the cerebrospinal fluid (CSF) is one approach to circumvent the blood-brain barrier and focus delivery of drugs to the site of tumor. However, high rates of CSF turnover prevent adequate drug accumulation and lead to rapid systemic clearance and toxicity. Here, we show that PLA-HPG nanoparticles, made with a single-emulsion, solvent evaporation process, can encapsulate talazoparib, a PARP inhibitor (BMN-673). These degradable polymer nanoparticles improve the therapeutic index when delivered intrathecally and lead to sustained drug retention in the tumor as measured with PET imaging and fluorescence microscopy. We demonstrate that administration of these particles into the CSF, alone or in combination with systemically administered temozolomide, is a highly effective therapy for tumor regression and prevention of leptomeningeal spread in xenograft mouse models of medulloblastoma. These results provide a rationale for harnessing nanoparticles for the delivery of drugs limited by brain penetration and therapeutic index and demonstrate important advantages in tolerability and efficacy for encapsulated drugs delivered locoregionally.


Asunto(s)
Antineoplásicos , Neoplasias Cerebelosas , Meduloblastoma , Nanopartículas , Niño , Humanos , Ratones , Animales , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Meduloblastoma/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Neoplasias Cerebelosas/tratamiento farmacológico , Líquido Cefalorraquídeo
10.
Stroke ; 54(9): 2296-2303, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37551589

RESUMEN

BACKGROUND: Poststroke cognitive impairment (PSCI) occurs in about half of stroke survivors. Cumulative evidence indicates that functional outcomes of stroke are worse in women than men. Yet it is unknown whether the occurrence and characteristics of PSCI differ between men and women. METHODS: Individual patient data from 9 cohorts of patients with ischemic stroke were harmonized and pooled through the Meta-VCI-Map consortium (n=2343, 38% women). We included patients with visible symptomatic infarcts on computed tomography/magnetic resonance imaging and cognitive assessment within 15 months after stroke. PSCI was defined as impairment in ≥1 cognitive domains on neuropsychological assessment. Logistic regression analyses were performed to compare men to women, adjusted for study cohort, to obtain odds ratios for PSCI and individual cognitive domains. We also explored sensitivity and specificity of cognitive screening tools for detecting PSCI, according to sex (Mini-Mental State Examination, 4 cohorts, n=1814; Montreal Cognitive Assessment, 3 cohorts, n=278). RESULTS: PSCI was found in 51% of both women and men. Men had a lower risk of impairment of attention and executive functioning (men: odds ratio, 0.76 [95% CI, 0.61-0.96]), and language (men: odds ratio, 0.67 [95% CI, 0.45-0.85]), but a higher risk of verbal memory impairment (men: odds ratio, 1.43 [95% CI, 1.17-1.75]). The sensitivity of Mini-Mental State Examination (<25) for PSCI was higher for women (0.53) than for men (0.27; P=0.02), with a lower specificity for women (0.80) than men (0.96; P=0.01). Sensitivity and specificity of Montreal Cognitive Assessment (<26.) for PSCI was comparable between women and men (0.91 versus 0.86; P=0.62 and 0.29 versus 0.28; P=0.86, respectively). CONCLUSIONS: Sex was not associated with PSCI occurrence but affected domains differed between men and women. The latter may explain why sensitivity of the Mini-Mental State Examination for detecting PSCI was higher in women with a lower specificity compared with men. These sex differences need to be considered when screening for and diagnosing PSCI in clinical practice.


Asunto(s)
Disfunción Cognitiva , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Femenino , Masculino , Accidente Cerebrovascular Isquémico/complicaciones , Caracteres Sexuales , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/etiología , Accidente Cerebrovascular/epidemiología , Función Ejecutiva
11.
Appl Neuropsychol Adult ; : 1-13, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37459566

RESUMEN

Although bilingualism is widespread, little data on verbal fluency tasks (VFTs) within bilingualism subtypes and the underlying mechanisms exist. The study's objective was to explore executive and language processes in 10 semantic and letter VFTs and a set of language and executive tests among 100 elderly Arabic-French bilinguals from three bilingualism subgroups: Arabic-dominant, French-dominant, and balanced. We observed a prominent-language advantage for semantic and letter VFTs in French but not for letter VFTs in Arabic. This advantage in the VFT was associated with a sustained rate of late production, a higher percentage of specific words, a higher number of clusters, and a larger cluster size, and was related mainly to language processes. Our results suggest that the strategic search processes underlying VFTs operate on the two phonological output lexicons of bilinguals with similar characteristics in different languages and thus support the hypothesis of a single, centralized, strategic search process.

12.
Res Sq ; 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37333156

RESUMEN

Understanding interactions between adoptively transferred immune cells and the tumor immune microenvironment (TIME) is critical for developing successful T-cell based immunotherapies. Here we investigated the impact of the TIME and chimeric antigen receptor (CAR) design on anti-glioma activity of B7-H3-specific CAR T-cells. We show that five out of six B7-H3 CARs with varying transmembrane, co-stimulatory, and activation domains, exhibit robust functionality in vitro. However, in an immunocompetent glioma model, these CAR T-cells demonstrated significantly varied levels of anti-tumor activity. We used single-cell RNA sequencing to examine the brain TIME after CAR T-cell therapy. We show that the TIME composition was influenced by CAR T-cell treatment. We also found that successful anti-tumor responses were supported by the presence and activity of macrophages and endogenous T-cells. Together, our study demonstrates that efficacy of CAR T-cell therapy in high-grade glioma is dependent on CAR structural design and its capacity to modulate the TIME.

14.
J Neurooncol ; 163(1): 143-158, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37183219

RESUMEN

PURPOSE: We and others have demonstrated that MYC-amplified medulloblastoma (MB) cells are susceptible to class I histone deacetylase inhibitor (HDACi) treatment. However, single drug treatment with HDACi has shown limited clinical efficacy. We hypothesized that addition of a second compound acting synergistically with HDACi may enhance efficacy. METHODS: We used a gene expression dataset to identify PLK1 as a second target in MB cells and validated the relevance of PLK1 in MB. We measured cell metabolic activity, viability, and cycle progression in MB cells after treatment with PLK1-specific inhibitors (PLK1i). Chou-Talalay synergy calculations were used to determine the nature of class I HDACi entinostat and PLK1i interaction which was validated. Finally, the clinical potential of the combination was assessed in the in vivo experiment. RESULTS: MYC-amplified tumor cells are highly sensitive towards treatment with ATP-competitive PLK1i as a monotherapy. Entinostat and PLK1i in combination act synergistically in MYC-driven MB cells, exerting cytotoxic effects at clinically relevant concentrations. The downstream effect is exerted via MYC-related pathways, pointing out the potential of MYC amplification as a clinically feasible predictive biomarker for patient selection. While entinostat significantly extended survival of mice implanted with orthotopic MYC-amplified MB PDX, there was no evidence of the improvement of survival when treating the animals with the combination. CONCLUSION: The combination of entinostat and PLK1i showed synergistic interaction in vitro, but not in vivo. Therefore, further screening of blood-brain barrier penetrating PLK1i is warranted to determine the true potential of the combination as no on-target activity was observed after PLK1i volasertib treatment in vivo.


Asunto(s)
Antineoplásicos , Neoplasias Cerebelosas , Meduloblastoma , Ratones , Animales , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Histona Desacetilasas/uso terapéutico , Meduloblastoma/tratamiento farmacológico , Meduloblastoma/metabolismo , Antineoplásicos/uso terapéutico , Neoplasias Cerebelosas/tratamiento farmacológico , Línea Celular Tumoral
15.
Cortex ; 164: 129-143, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37207410

RESUMEN

The functional organization and related anatomy of executive functions are still largely unknown and were examined in the present study using a verbal fluency task. The objective of this study was to determine the cognitive architecture of a fluency task and related voxelwise anatomy in the GRECogVASC cohort and fMRI based meta-analytical data. First, we proposed a model of verbal fluency in which two control processes, lexico-semantic strategic search process and attention process, interact with semantic and lexico-phonological output processes. This model was assessed by testing 404 patients and 775 controls for semantic and letter fluency, naming, and processing speed (Trail Making test part A). Regression (R2 = .276 and .3, P = .0001, both) and structural equation modeling (CFI: .88, RMSEA: .2, SRMR: .1) analyses supported this model. Second, voxelwise lesion-symptom mapping and disconnectome analyses demonstrated fluency to be associated with left lesions of the pars opercularis, lenticular nucleus, insula, temporopolar region, and a large number of tracts. In addition, a single dissociation showed specific association of letter fluency with the pars triangularis of F3. Disconnectome mapping showed the additional role of disconnection of left frontal gyri and thalamus. By contrast, these analyses did not identify voxels specifically associated with lexico-phonological search processes. Third, meta-analytic fMRI data (based on 72 studies) strikingly matched all structures identified by the lesion approach. These results support our modeling of the functional architecture of verbal fluency based on two control processes (strategic search and attention) operating on semantic and lexico-phonologic output processes. Multivariate analysis supports the prominent role of the temporopolar area (BA 38) in semantic fluency and the F3 triangularis area (BA 45) in letter fluency. Finally, the lack of voxels specifically dedicated to strategic search processes could be due to a distributed organization of executive functions warranting further studies.


Asunto(s)
Mapeo Encefálico , Accidente Cerebrovascular , Humanos , Mapeo Encefálico/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/psicología , Semántica , Corteza Prefrontal , Área de Broca , Pruebas Neuropsicológicas
16.
Oncogene ; 42(20): 1661-1671, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37020038

RESUMEN

Atypical teratoid/rhabdoid tumors (ATRTs) represent a rare, but aggressive pediatric brain tumor entity. They are genetically defined by alterations in the SWI/SNF chromatin remodeling complex members SMARCB1 or SMARCA4. ATRTs can be further classified in different molecular subgroups based on their epigenetic profiles. Although recent studies suggest that the different subgroups have distinct clinical features, subgroup-specific treatment regimens have not been developed thus far. This is hampered by the lack of pre-clinical in vitro models representative of the different molecular subgroups. Here, we describe the establishment of ATRT tumoroid models from the ATRT-MYC and ATRT-SHH subgroups. We demonstrate that ATRT tumoroids retain subgroup-specific epigenetic and gene expression profiles. High throughput drug screens on our ATRT tumoroids revealed distinct drug sensitivities between and within ATRT-MYC and ATRT-SHH subgroups. Whereas ATRT-MYC universally displayed high sensitivity to multi-targeted tyrosine kinase inhibitors, ATRT-SHH showed a more heterogeneous response with a subset showing high sensitivity to NOTCH inhibitors, which corresponded to high expression of NOTCH receptors. Our ATRT tumoroids represent the first pediatric brain tumor organoid model, providing a representative pre-clinical model which enables the development of subgroup-specific therapies.


Asunto(s)
Neoplasias Encefálicas , Tumor Rabdoide , Teratoma , Niño , Humanos , Teratoma/tratamiento farmacológico , Teratoma/genética , Proteína SMARCB1/genética , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Tumor Rabdoide/tratamiento farmacológico , Tumor Rabdoide/genética , Tumor Rabdoide/metabolismo , Receptores Notch , Epigenómica , ADN Helicasas , Proteínas Nucleares , Factores de Transcripción/genética
17.
Neurology ; 100(23): e2331-e2341, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37072222

RESUMEN

BACKGROUND AND OBJECTIVES: Past studies on poststroke cognitive function have focused on the average performance or change over time, but few have investigated patterns of cognitive trajectories after stroke. This project used latent class growth analysis (LCGA) to identify clusters of patients with similar patterns of cognition scores over the first-year poststroke and the extent to which long-term cognitive outcome is predicted by the clusters ("trajectory groups"). METHODS: Data were sought from the Stroke and Cognition consortium. LCGA was used to identify clusters of trajectories based on standardized global cognition scores at baseline (T1) and at the 1-year follow-up (T2). One-step individual participant data meta-analysis was used to examine risk factors for trajectory groups and association of trajectory groups with cognition at the long-term follow-up (T3). RESULTS: Nine hospital-based stroke cohorts with 1,149 patients (63% male; mean age 66.4 years [SD 11.0]) were included. The median time assessed at T1 was 3.6 months poststroke, 1.0 year at T2, and 3.2 years at T3. LCGA identified 3 trajectory groups, which were characterized by different mean levels of cognition scores at T1 (low-performance, -3.27 SD [0.94], 17%; medium-performance, -1.23 SD [0.68], 48%; and high-performance, 0.71 SD [0.77], 35%). There was significant improvement in cognition for the high-performance group (0.22 SD per year, 95% CI 0.07-0.36), but changes for the low-performance and medium-performance groups were not significant (-0.10 SD per year, 95% CI -0.33 to 0.13; 0.11 SD per year, 95% CI -0.08 to 0.24, respectively). Factors associated with the low- (vs high-) performance group include age (relative risk ratio [RRR] 1.18, 95% CI 1.14-1.23), years of education (RRR 0.61, 95% CI 0.56-0.67), diabetes (RRR 3.78, 95% CI 2.08-6.88), large artery vs small vessel strokes (RRR 2.77, 95% CI 1.32-5.83), and moderate/severe strokes (RRR 3.17, 95% CI 1.42-7.08). Trajectory groups were predictive of global cognition at T3, but its predictive power was comparable with scores at T1. DISCUSSION: The trajectory of cognitive function over the first-year poststroke is heterogenous. Baseline cognitive function ∼3.6 months poststroke is a good predictor of long-term cognitive outcome. Older age, lower levels of education, diabetes, large artery strokes, and greater stroke severity are risk factors for lower cognitive performance over the first year.


Asunto(s)
Trastornos del Conocimiento , Disfunción Cognitiva , Accidente Cerebrovascular , Humanos , Masculino , Anciano , Femenino , Cognición , Trastornos del Conocimiento/complicaciones , Factores de Riesgo , Disfunción Cognitiva/psicología
18.
Eur J Med Chem ; 251: 115246, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-36898329

RESUMEN

An X-ray structure of a CLICK chemistry-based BET PROTAC bound to BRD2(BD2) inspired synthesis of JQ1 derived heterocyclic amides. This effort led to the discovery of potent BET inhibitors displaying overall improved profiles when compared to JQ1 and birabresib. A thiadiazole derived 1q (SJ1461) displayed excellent BRD4 and BRD2 affinity and high potency in the panel of acute leukaemia and medulloblastoma cell lines. A structure of 1q co-crystalised with BRD4-BD1 revealed polar interactions with the AZ/BC loops, in particular with Asn140 and Tyr139, rationalising the observed affinity improvements. In addition, exploration of pharmacokinetic properties of this class of compounds suggest that the heterocyclic amide moiety improves drug-like features. Our study led to the discovery of potent and orally bioavailable BET inhibitor 1q (SJ1461) as a promising candidate for further development.


Asunto(s)
Proteínas Nucleares , Factores de Transcripción , Proteínas Nucleares/metabolismo , Factores de Transcripción/metabolismo , Línea Celular , Proteínas de Ciclo Celular/metabolismo
19.
Trials ; 24(1): 172, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36890548

RESUMEN

BACKGROUND: Gait disorders and cognitive impairments are prime causes of disability and institutionalization after stroke. We hypothesized that relative to single-task gait rehabilitation (ST GR), cognitive-motor dual-task (DT) GR initiated at the subacute stage would be associated with greater improvements in ST and DT gait, balance, and cognitive performance, personal autonomy, disability, and quality of life in the short, medium and long terms after stroke. METHODS: This multicenter (n=12), two-arm, parallel-group, randomized (1:1), controlled clinical study is a superiority trial. With p<0.05, a power of 80%, and an expected loss to follow-up rate of 10%, the inclusion of 300 patients will be required to evidence a 0.1-m.s-1 gain in gait speed. Trial will include adult patients (18-90 years) in the subacute phase (0 to 6 months after a hemispheric stroke) and who are able to walk for 10 m (with or without a technical aid). Registered physiotherapists will deliver a standardized GR program (30 min three times a week, for 4 weeks). The GR program will comprise various DTs (phasic, executive function, praxis, memory, and spatial cognition tasks during gait) in the DT (experimental) group and gait exercises only in the ST (control) group. The primary outcome measure is gait speed 6 months after inclusion. The secondary outcomes are post-stroke impairments (National Institutes of Health Stroke Scale and the motor part of the Fugl-Meyer Assessment of the lower extremity), gait speed (10-m walking test), mobility and dynamic balance (timed up-and-go test), ST and DT cognitive function (the French adaptation of the harmonization standards neuropsychological battery, and eight cognitive-motor DTs), personal autonomy (functional independence measure), restrictions in participation (structured interview and the modified Rankin score), and health-related quality of life (on a visual analog scale). These variables will be assessed immediately after the end of the protocol (probing the short-term effect), 1 month thereafter (the medium-term effect), and 5 months thereafter (the long-term effect). DISCUSSION: The main study limitation is the open design. The trial will focus on a new GR program applicable at various stages after stroke and during neurological disease. TRIAL REGISTRATION: NCT03009773 . Registered on January 4, 2017.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Adulto , Humanos , Rehabilitación de Accidente Cerebrovascular/métodos , Calidad de Vida , Marcha , Caminata , Terapia por Ejercicio/métodos , Cognición , Resultado del Tratamiento , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
20.
Cortex ; 160: 55-66, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36745966

RESUMEN

Apathy occurs in approximately one third of people after stroke. Despite its frequency and functional consequences, the determinants of apathy have only been partially defined. The major difficulty lies in disentangling the reduction in activity due to apathy itself from those secondary to comorbidities, such as depression, sensorimotor deficits, and cognitive impairment. Here, we aimed to examine the prevalence of apathy, identify confounding sources of hypoactivity, and define its neuroimaging determinants using multivariate voxel lesion symptom-mapping (mVLSM) analyses. We assessed apathy in a subgroup (n = 325, mean age: 63.8 ± 10.5 years, 91.1% ischemic stroke) of the GRECogVASC cohort using the validated Behavioral Dysexecutive Syndrome Inventory, interpreted using GREFEX criteria, as well as confounding factors (depression, anxiety, severity of the neurological deficit, and gait disorders). mVLSM analysis was used to define neuroimaging determinants and was repeated after controlling for confounding factors. Apathy was present for 120 patients (36.9%, 95% CI: 31.7-42.2). Stepwise linear regression identified three factors associated with apathy: depressive symptoms (R2 = .3, p = .0001), cognitive impairment (R2 = .015, p = .02), and neurological deficit (R2 = .110, p = .0001). Accordingly, only 9 (7.5%) patients had apathy without a confounding factor, i.e., isolated apathy. In conventional VLSM analysis, apathy was associated with a large number of subcortical lesions that were no longer considered after controlling for confounding factors. Strategic site analysis identified five regions associated with isolated apathy: the F3 orbitalis pars, left amygdala, left thalamus, left pallidum, and mesencephalon. mVLSM analysis identified four strategic sites associated with apathy: the right corticospinal tract (R2 = .11; p = .0001), left frontostriatal tract (R2 = .11; p = .0001), left thalamus (R2 = .04; p = .0001), and left amygdala (R2 = .01; p = .013). These regions remained significant after controlling for confounding factors but explained a lower amount of variance. These findings indicate that poststroke apathy is more strongly associated with depression, neurological deficit, and cognitive impairment than with stroke lesions locations, at least using VLSM analysis.


Asunto(s)
Apatía , Disfunción Cognitiva , Accidente Cerebrovascular , Humanos , Persona de Mediana Edad , Anciano , Imagen por Resonancia Magnética , Pruebas Neuropsicológicas , Disfunción Cognitiva/psicología , Cognición , Depresión
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