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1.
Cell ; 178(4): 835-849.e21, 2019 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-31327527

RESUMEN

Diverse genetic, epigenetic, and developmental programs drive glioblastoma, an incurable and poorly understood tumor, but their precise characterization remains challenging. Here, we use an integrative approach spanning single-cell RNA-sequencing of 28 tumors, bulk genetic and expression analysis of 401 specimens from the The Cancer Genome Atlas (TCGA), functional approaches, and single-cell lineage tracing to derive a unified model of cellular states and genetic diversity in glioblastoma. We find that malignant cells in glioblastoma exist in four main cellular states that recapitulate distinct neural cell types, are influenced by the tumor microenvironment, and exhibit plasticity. The relative frequency of cells in each state varies between glioblastoma samples and is influenced by copy number amplifications of the CDK4, EGFR, and PDGFRA loci and by mutations in the NF1 locus, which each favor a defined state. Our work provides a blueprint for glioblastoma, integrating the malignant cell programs, their plasticity, and their modulation by genetic drivers.


Asunto(s)
Neoplasias Encefálicas/genética , Plasticidad de la Célula/genética , Glioblastoma/genética , Adolescente , Anciano , Animales , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Linaje de la Célula/genética , Niño , Estudios de Cohortes , Modelos Animales de Enfermedad , Femenino , Heterogeneidad Genética , Glioblastoma/patología , Xenoinjertos , Humanos , Lactante , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Persona de Mediana Edad , Mutación , RNA-Seq , Análisis de la Célula Individual/métodos , Microambiente Tumoral/genética
2.
Nature ; 549(7671): 227-232, 2017 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-28854171

RESUMEN

Human glioblastomas harbour a subpopulation of glioblastoma stem cells that drive tumorigenesis. However, the origin of intratumoural functional heterogeneity between glioblastoma cells remains poorly understood. Here we study the clonal evolution of barcoded glioblastoma cells in an unbiased way following serial xenotransplantation to define their individual fate behaviours. Independent of an evolving mutational signature, we show that the growth of glioblastoma clones in vivo is consistent with a remarkably neutral process involving a conserved proliferative hierarchy rooted in glioblastoma stem cells. In this model, slow-cycling stem-like cells give rise to a more rapidly cycling progenitor population with extensive self-maintenance capacity, which in turn generates non-proliferative cells. We also identify rare 'outlier' clones that deviate from these dynamics, and further show that chemotherapy facilitates the expansion of pre-existing drug-resistant glioblastoma stem cells. Finally, we show that functionally distinct glioblastoma stem cells can be separately targeted using epigenetic compounds, suggesting new avenues for glioblastoma-targeted therapy.


Asunto(s)
Diferenciación Celular , Linaje de la Célula , Rastreo Celular , Glioblastoma/patología , Células Madre Neoplásicas/patología , Animales , Diferenciación Celular/efectos de los fármacos , Linaje de la Célula/efectos de los fármacos , Proliferación Celular , Células Clonales/efectos de los fármacos , Células Clonales/patología , Epigénesis Genética , Femenino , Glioblastoma/tratamiento farmacológico , Xenoinjertos , Humanos , Ratones , Invasividad Neoplásica , Trasplante de Neoplasias , Células Madre Neoplásicas/efectos de los fármacos , Fenotipo , Procesos Estocásticos
3.
Proc Natl Acad Sci U S A ; 112(3): 851-6, 2015 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-25561528

RESUMEN

Glioblastoma (GBM) is a cancer comprised of morphologically, genetically, and phenotypically diverse cells. However, an understanding of the functional significance of intratumoral heterogeneity is lacking. We devised a method to isolate and functionally profile tumorigenic clones from patient glioblastoma samples. Individual clones demonstrated unique proliferation and differentiation abilities. Importantly, naïve patient tumors included clones that were temozolomide resistant, indicating that resistance to conventional GBM therapy can preexist in untreated tumors at a clonal level. Further, candidate therapies for resistant clones were detected with clone-specific drug screening. Genomic analyses revealed genes and pathways that associate with specific functional behavior of single clones. Our results suggest that functional clonal profiling used to identify tumorigenic and drug-resistant tumor clones will lead to the discovery of new GBM clone-specific treatment strategies.


Asunto(s)
Neoplasias Encefálicas/patología , Glioblastoma/patología , Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Dacarbazina/análogos & derivados , Dacarbazina/uso terapéutico , Resistencia a Antineoplásicos , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Humanos , Análisis de la Célula Individual , Temozolomida
4.
Gut Microbes ; 16(1): 2353396, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38778483

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that leads to respiratory failure, and eventually death. However, there is a lack of effective treatments for ALS. Here we report the results of fecal microbiota transplantation (FMT) in two patients with late-onset classic ALS with a Japan ALS severity classification of grade 5 who required tracheostomy and mechanical ventilation. In both patients, significant improvements in respiratory function were observed following two rounds of FMT, leading to weaning off mechanical ventilation. Their muscle strength improved, allowing for assisted standing and mobility. Other notable treatment responses included improved swallowing function and reduced muscle fasciculations. Metagenomic and metabolomic analysis revealed an increase in beneficial Bacteroides species (Bacteroides stercoris, Bacteroides uniformis, Bacteroides vulgatus), and Faecalibacterium prausnitzii after FMT, as well as elevated levels of metabolites involved in arginine biosynthesis and decreased levels of metabolites involved in branched-chain amino acid biosynthesis. These findings offer a potential rescue therapy for ALS with respiratory failure and provide new insights into ALS in general.


Asunto(s)
Esclerosis Amiotrófica Lateral , Trasplante de Microbiota Fecal , Insuficiencia Respiratoria , Humanos , Esclerosis Amiotrófica Lateral/terapia , Esclerosis Amiotrófica Lateral/microbiología , Bacteroides , Faecalibacterium prausnitzii , Heces/microbiología , Microbioma Gastrointestinal , Respiración Artificial , Insuficiencia Respiratoria/terapia , Insuficiencia Respiratoria/microbiología , Resultado del Tratamiento
5.
Epileptic Disord ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38896014

RESUMEN

OBJECTIVE: This study aimed to analyze the clinical characteristics, etiology, and treatment of midlife-onset epilepsy in a real-world setting at a single center in China. METHODS: The clinical data of patients who attended the epilepsy clinic of the Department of Neurology, First Medical Center of Chinese PLA General Hospital from February 1999 to March 2023 were retrospectively analyzed. The clinical characteristics, etiology, and risk factors for midlife-onset epilepsy over the past 24 years were analyzed. RESULTS: Of the 969 patients with onset at 45-64 years of age, 914 were diagnosed with epilepsy with at least two unprovoked seizures 24 h apart. Of those, 99.7% (911) were of focal origin. The median duration from the initial seizure to follow-up treatment was 2 months (interquartile range [IQR]: 1.0-6.0 months). Before commencing treatment, 30.2% (207/683) of patients experienced more than two seizures. A structural etiology was found in 66.3% (606/914) of patients. Cerebrovascular disease (CVD) and traumatic brain injury (TBI) accounted for 19.9% (182/914) and 16.6% (152/914) of the cases, respectively. Logistic regression analysis showed that patients with abnormal imaging (odds ratio [OR] 2.04; 95% confidence interval [CI] 1.25-3.32; p = .004), focal seizures (OR 2.98; 95%CI 1.82-4.87; p < .001), and seizure clusters (OR 2.40; 95%CI 1.21-4.73; p = .01) had poor drug responses. Treatment outcomes were generally better in patients with epilepsy after CVD (OR .49; 95%CI .28-.85; p = .01). Treatment initiation after two seizures (OR .70; 95%CI .42-1.15; p = .16) or 6 months after the first seizure (OR 1.17; 95%CI .66-2.09; p = .58) did not result in poor drug effectiveness. SIGNIFICANCE: Midlife-onset epilepsy is typically of focal etiology, with CVD being the most common cause, and tends to respond well to medication. The median duration from the initial seizure to follow-up treatment was 2 months. Over 30% of patients experienced more than two seizures before commencing treatment, but this did not affect subsequent outcomes.

6.
Cancers (Basel) ; 15(4)2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36831673

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is the most common malignancy of the pancreas and is associated with an extremely poor prognosis. Many PDAC patients suffer from profound nutritional complications such as nutrient deficiencies, weight loss, malnutrition, and cancer cachexia. These complications cause barriers to effective anticancer treatments, gravely influence their quality of life, and decrease their overall survival. Pancreatic exocrine insufficiency (PEI) is defined as impaired digestion due to inadequate secretion of pancreatic enzymes and is a common cause of malnutrition in PDAC. This review first summarizes the existing literature around malnutrition in PDAC, with a particular focus on PEI and its management with pancreatic enzyme replacement therapy (PERT). Second, we summarize existing guidelines and recommendations for the management of PEI among patients with PDAC. Lastly, we highlight potential gaps of knowledge of PEI among healthcare providers resulting in underdiagnosis and treatment, which may have implications for the quality of life and overall survival of PDAC patients.

7.
PLoS One ; 18(9): e0291457, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37708198

RESUMEN

BACKGROUND: Fatigue and burnout are prevalent among resident physicians across Canada. Shifts exceeding 24 hours are commonly purported as detrimental to resident health and performance. Residency training programs have employed strategies towards understanding and intervening upon the complex issue of resident fatigue, where alternative resident scheduling models have been an area of active investigation. This study sought to characterize drivers and outcomes of fatigue and burnout amongst internal medicine residents across different scheduling models. METHODS: We conducted cross-sectional surveys were among internal medicine resident physicians at the University of Alberta. We collected anonymized socioeconomic demographics and medical education background, and estimated associations between demographic or work characteristics and fatigue and burnout outcomes. RESULTS: Sixty-nine participants competed burnout questionnaires, and 165 fatigue questionnaires were completed (response rate of 48%). The overall prevalence of burnout was 58%. Lower burnout prevalence was noted among respondents with dependent(s) (p = 0.048), who identified as a racial minority (p = 0.018), or completed their medical degree internationally (p = 0.006). The 1-in-4 model was associated with the highest levels of fatigue, reported increased risk towards personal health (OR 4.98, 95%CI 1.77-13.99) and occupational or household harm (OR 5.69, 95%CI 1.87-17.3). Alternative scheduling models were not associated with these hazards. CONCLUSIONS: The 1-in-4 scheduling model was associated with high rates of resident physician fatigue, and alternative scheduling models were associated with less fatigue. Protective factors against fatigue are best characterized as strong social supports outside the workplace. Further studies are needed to characterize the impacts of alternative scheduling models on resident education and patient safety.


Asunto(s)
Agotamiento Psicológico , Fatiga , Humanos , Estudios Transversales , Canadá/epidemiología , Fatiga/epidemiología , Medicina Interna
8.
Exp Ther Med ; 23(1): 42, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34849157

RESUMEN

Lidocaine, a local anesthetic, is a valuable agent for the treatment of neuronal ischemia/reperfusion (I/R) injury. The aim of the present study was to investigate the role of lidocaine in oxygen-glucose deprivation/reperfusion (OGD/R)-induced cortical neurons and explore the related molecular mechanisms. Cerebral cortical neurons were isolated from Sprague-Dawley rat embryos and stimulated with OGD/R to establish an in vitro I/R injury model. Subsequently, neuronal cell viability, cytotoxicity and apoptosis were evaluated by performing the MTT assay, lactate dehydrogenase (LDH) assay and flow cytometry, respectively. The results suggested that OGD/R exposure significantly decreased cerebral cortical neuron cell viability, accelerated LDH release and induced cell apoptosis compared with control neurons, indicating that cerebral I/R injury was stimulated by OGD/R treatment. Further investigation indicated that 10 µM lidocaine significantly enhanced neuronal cell viability, and reduced LDH release and neuronal cell apoptosis in OGD/R-exposed cells compared with the OGD/R + saline group, which indicated that lidocaine displayed neuroprotective effects against I/R damage. In addition, the findings of the present study suggested that OGD/R exposure significantly decreased Bcl-2 and Bcl-xl protein expression levels, but increased Bax protein expression levels, the Bax/Bcl-2 ratio and caspase-3 activity compared with control neurons. However, lidocaine reversed OGD/R-mediated alterations to apoptosis-related protein expression. Furthermore, the results of the present study indicated that lidocaine increased Wnt3a, ß-catenin and cyclin D1 expression levels in OGD/R-exposed cells compared with the OGD/R + saline group, thus activating the Wnt/ß-catenin signaling pathway. The findings of the present study suggested that lidocaine served a protective role in OGD/R-triggered neuronal damage by activating the Wnt/ß-catenin signaling pathway; therefore, lidocaine may serve as a potential candidate for the treatment of cerebral I/R injury.

9.
Metabolites ; 12(11)2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36422290

RESUMEN

Obesity is a major burden for modern medicine, with many links to negative health outcomes, including the increased incidence of certain cancer types. Interestingly, some studies have supported the concept of an "Obesity Paradox", where some cancer patients living with obesity have been shown to have a better prognosis than non-obese patients. Neuroendocrine neoplasms (NENs) are malignancies originating from neuroendocrine cells, in some cases retaining important functional properties with consequences for metabolism and nutritional status. In this review, we summarize the existing evidence demonstrating that obesity is both a risk factor for developing NENs as well as a good prognostic factor. We further identify the limitations of existing studies and further avenues of research that will be necessary to optimize the metabolic and nutritional status of patients living with NENs to ensure improved outcomes.

10.
Front Aging Neurosci ; 13: 687824, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34239437

RESUMEN

Background: There is a strong need for short and effective methods to screen for cognitive impairment. Recent studies have created short forms of the Montreal Cognitive Assessment (s-MoCA) in English-speaking populations. It is also important to develop a validated Chinese short version to detect cognitive impairment. Methods: Item response theory and computerized adaptive testing analytics were used to construct abbreviated MoCAs across a large neurological sample comprising 6,981 community-dwelling Chinese veterans. Results: Six MoCA items with high discrimination and appropriate difficulty were included in the s-MoCA. The Chinese short versions (sensitivity 0.89/0.90, specificity 0.72/0.77) are similar in performance to the full MoCA in identifying cognitive impairment (sensitivity 0.91, specificity 0.82). Conclusions: These short variants of the MoCA may serve as quick and effective instruments when the original MoCA cannot be feasibly administered in clinical services with a high patient burden and limited cognitive testing resources.

11.
Nat Commun ; 12(1): 979, 2021 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-33579912

RESUMEN

Glioblastoma (GBM) is a deadly cancer in which cancer stem cells (CSCs) sustain tumor growth and contribute to therapeutic resistance. Protein arginine methyltransferase 5 (PRMT5) has recently emerged as a promising target in GBM. Using two orthogonal-acting inhibitors of PRMT5 (GSK591 or LLY-283), we show that pharmacological inhibition of PRMT5 suppresses the growth of a cohort of 46 patient-derived GBM stem cell cultures, with the proneural subtype showing greater sensitivity. We show that PRMT5 inhibition causes widespread disruption of splicing across the transcriptome, particularly affecting cell cycle gene products. We identify a GBM splicing signature that correlates with the degree of response to PRMT5 inhibition. Importantly, we demonstrate that LLY-283 is brain-penetrant and significantly prolongs the survival of mice with orthotopic patient-derived xenografts. Collectively, our findings provide a rationale for the clinical development of brain penetrant PRMT5 inhibitors as treatment for GBM.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Proteína-Arginina N-Metiltransferasas/metabolismo , Animales , Apoptosis , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Descubrimiento de Drogas , Epigenómica , Femenino , Regulación Neoplásica de la Expresión Génica , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/patología , Humanos , Ratones , Células Madre Neoplásicas/metabolismo , Proteína-Arginina N-Metiltransferasas/efectos de los fármacos , Proteína-Arginina N-Metiltransferasas/genética , Empalme del ARN , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Medicine (Baltimore) ; 99(44): e22911, 2020 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-33126348

RESUMEN

The aim of this study was to investigate the clinical characteristics of central nervous system (CNS) aspergillosis in immunocompetent patients.This study enrolled six immunocompetent patients diagnosed with CNS aspergillosis. Additionally, we reviewed the clinical profiles for 28 cases reported in the literature. The age, gender, etiology of Aspergillus infection, clinical manifestations, location of the lesion, treatment, and prognosis were analyzed.There were 19 men (average age, 54.6 ±â€Š14.3 years) and 15 women (average age, 47.0 ±â€Š19.4 years). The clinical manifestations included headache (55.9%; n = 19), visual impairment (32.4%; n = 11), diplopia (32.4%; n = 11), hemiplegia (20.6%; n = 7), fever (17.6%; n = 6), and epilepsy (8.8%; n = 3). According to the radiological features, CNS aspergillosis lesions were divided into two subtypes: parenchymal lesions in the cerebral lobes (n = 11), and meningeal lesions in the meninges (n = 23). The patients with meningeal lesions are easy to be complicated with more serious cerebrovascular diseases, such as subarachnoid hemorrhage and massive infarction. Most of the lesions in brain parenchyma were abscess formation, and magnetic resonance imaging showed ring enhancement. The clinical diagnosis of Aspergillus infection was mainly based on brain biopsy (n = 14), autopsy (n = 8), pathological examination of adjacent brain tissues (n = 7), cerebrospinal fluid (CSF) or tissue culture (n = 3), and second-generation sequencing analysis of the CSF (n = 3). Clinical improvement was achieved in 23 cases, and 11 patients succumbed to the disease. Voriconazole treatment was effective in 24 (70.6%) cases.Immunocompetent subjects are also at risk for Aspergillus infections. Concomitant cerebrovascular diseases are common in patients with CNS aspergillosis, especially in patients with meningeal aspergillosis. Parenchymal aspergillosis lesions are usually localized and manifest as brain abscesses with annular enhancement on magnetic resonance imaging. Biopsy, CSF culture, and next-generation sequencing are mainstream diagnostic modalities. Voriconazole is an effective treatment for Aspergillus infection, and early diagnosis and treatment should be highlighted.


Asunto(s)
Absceso Encefálico , Encéfalo , Inmunocompetencia , Meningitis Fúngica , Neuroaspergilosis , Hemorragia Subaracnoidea , Voriconazol/uso terapéutico , Adulto , Antifúngicos/uso terapéutico , Biopsia/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/microbiología , Encéfalo/patología , Absceso Encefálico/diagnóstico , Absceso Encefálico/etiología , Diagnóstico , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Meningitis Fúngica/diagnóstico , Meningitis Fúngica/etiología , Persona de Mediana Edad , Neuroaspergilosis/líquido cefalorraquídeo , Neuroaspergilosis/diagnóstico , Neuroaspergilosis/tratamiento farmacológico , Neuroaspergilosis/fisiopatología , Hemorragia Subaracnoidea/diagnóstico , Hemorragia Subaracnoidea/etiología , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento
13.
J Alzheimers Dis ; 77(2): 667-674, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32741811

RESUMEN

BACKGROUND: Over time, improved cognitive abilities in elderly individuals lead to an overall increase in performance on widely used cognitive screening tests (e.g., Mini-Mental State Examination, MMSE) and impact screening efficacy. OBJECTIVE: We aimed to examine the epoch effect on cognitive function measured using MMSE, in addition to the influence of demographic characteristics on MMSE. We also evaluated the ability of the MMSE in detecting dementia and examined the discrimination ability and measurement precision of the MMSE. METHODS: In a cross-sectional survey, Chinese veterans aged ≥60 years were interviewed. Multiple linear regression analysis was applied to explore the factors affecting the MMSE. The expected MMSE score was calculated to examine the epoch effect. The diagnostic accuracy of the MMSE was determined via receiver operating characteristic curve analyses. Item response theory methods were implemented using Stata 16.0. RESULTS: The MMSE score increased with higher education and decreased with advancing age. The observed MMSE score in this study (26.9) was higher than the expected MMSE score (24.9). It demonstrated 78.3% /84.1% /89.9% sensitivity and 85.8% /79.5% /66.8% specificity in detecting dementia using the cut-off score 25/26/27. The MMSE showed reduced discrimination and provided little information for ability level of -1 and above. CONCLUSION: Improved cognitive ability over time may increase the performance on cognitive screening tests (e.g., MMSE). This impact of epoch in cognitive function emphasizes the importance of regularly updating cognitive screening tests.


Asunto(s)
Cognición/fisiología , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/epidemiología , Pruebas de Estado Mental y Demencia/normas , Anciano , Anciano de 80 o más Años , China/epidemiología , Disfunción Cognitiva/psicología , Estudios Transversales , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas/normas
14.
World Neurosurg ; 136: 311-314, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32004738

RESUMEN

BACKGROUND: Primary meningeal melanomatosis is a rare leptomeningeal tumor, and the diagnosis is challenging due to nonspecific clinical symptoms and radiologic findings. CASE DESCRIPTION: A 21-year-old man presented with recurrent seizure and impaired memory. Cranial magnetic resonance imaging showed obvious brain atrophy with bilateral extensive meningeal enhancement in the supratentorial region. Diffusion-weighted imaging and fluid-attenuated inversion recovery showed slightly hyperintensive signals in the cortex. Microscopic examination revealed invasion of pigment into the Virchow-Robin space and cortex. Immunohistochemical examination of biopsy samples showed that cells were immunopositive for HMB45 and S-100 and immunonegative for melan-A with a Ki-67-positive percentage of 3%. No obvious atypia or nuclear mitosis was observed. Pathohistologic results of biopsied meninges confirmed the diagnosis of diffuse meningeal melanomatosis. The disease was aggravated with the occurrence of brain atrophy, recurrent seizure, and declined higher cortical function. CONCLUSIONS: This case report illustrates that brain atrophy in meningeal melanomatosis is associated with a progressive decline of higher cortical function.


Asunto(s)
Encéfalo/patología , Melanoma/patología , Neoplasias Meníngeas/patología , Neoplasias Supratentoriales/patología , Atrofia/etiología , Biopsia , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Demencia/etiología , Imagen de Difusión por Resonancia Magnética , Progresión de la Enfermedad , Humanos , Masculino , Melanoma/complicaciones , Neoplasias Meníngeas/complicaciones , Convulsiones/etiología , Neoplasias Supratentoriales/complicaciones , Adulto Joven
15.
Cell Rep ; 31(2): 107511, 2020 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-32294450

RESUMEN

Medulloblastoma (MB) is a neoplasm linked to dysregulated cerebellar development. Previously, we demonstrated that the Sonic Hedgehog (SHH) subgroup grows hierarchically, with Sox2+ cells at the apex of tumor progression and relapse. To test whether this mechanism is rooted in a normal developmental process, we studied the role of Sox2 in cerebellar development. We find that the external germinal layer (EGL) is derived from embryonic Sox2+ precursors and that the EGL maintains a rare fraction of Sox2+ cells during the first postnatal week. Through lineage tracing and single-cell analysis, we demonstrate that these Sox2+ cells are within the Atoh1+ lineage, contribute extensively to adult granule neurons, and resemble Sox2+ tumor cells. Critically, constitutive activation of the SHH pathway leads to their aberrant persistence in the EGL and rapid tumor onset. We propose that failure to eliminate this rare but potent developmental population is the tumor initiation mechanism in SHH-subgroup MB.


Asunto(s)
Meduloblastoma/etiología , Meduloblastoma/metabolismo , Factores de Transcripción SOXB1/metabolismo , Animales , Linaje de la Célula/genética , Células Cultivadas , Neoplasias Cerebelosas/patología , Cerebelo/embriología , Femenino , Proteínas Hedgehog/metabolismo , Humanos , Masculino , Ratones Noqueados , Ratones Transgénicos , Recurrencia Local de Neoplasia/patología , Células-Madre Neurales/metabolismo , Neurogénesis , Neuronas/metabolismo , Factores de Transcripción SOXB1/fisiología , Transducción de Señal/fisiología , Análisis de la Célula Individual/métodos
17.
Arch Gerontol Geriatr ; 73: 43-49, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28755569

RESUMEN

OBJECTIVE: Although several statistical methods for adjusting for missing data have been developed and are widely applied in research, few studies have investigated these methods in adjusting for missingness in datasets that aim to estimate the prevalence of dementia. We attempted to develop a more feasible approach for handling missingness in a cross-sectional study among elderly. METHODS: Five methods of estimating prevalence, including stratified weighting (SW), inverse-probability weighting (IPW), hot deck imputation (HDI), ordinal logistic regression (OLR) and multiple imputation (MI), were applied to handle the missing data yielded by a dataset that include 2231 non-responders. RESULTS: Compared with the results of the complete case analysis, the differences in the prevalence rates of dementia and mild cognitive impairment (MCI) calculated by the prevalence-estimating methods after adjusting for non-responders were less than 7% and 6%, respectively. In contrast to the results of other methods, the estimated prevalence of dementia and MCI calculated by MI increased when more predictive factors were included, and the lowest rate of missing data was achieved using MI. Using the participants' ages, the cognitive screening sores and activity of daily life sores as predictive variables when correcting for missingness induced relatively larger effects on the estimated dementia prevalence. CONCLUSIONS: When adjusting for missingness while estimating the prevalence of dementia in cross-sectional studies, a simple method, such as SW, is recommended when limited information is available, whereas MI is the preferred method when additional information is available. Further simulation studies are needed to determine the optimal approach.


Asunto(s)
Disfunción Cognitiva/epidemiología , Interpretación Estadística de Datos , Demencia/epidemiología , Probabilidad , Anciano , Estudios Transversales , Femenino , Humanos , Modelos Logísticos , Masculino , Prevalencia
18.
Cell Stem Cell ; 21(2): 209-224.e7, 2017 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-28712938

RESUMEN

Glioblastomas exhibit a hierarchical cellular organization, suggesting that they are driven by neoplastic stem cells that retain partial yet abnormal differentiation potential. Here, we show that a large subset of patient-derived glioblastoma stem cells (GSCs) express high levels of Achaete-scute homolog 1 (ASCL1), a proneural transcription factor involved in normal neurogenesis. ASCL1hi GSCs exhibit a latent capacity for terminal neuronal differentiation in response to inhibition of Notch signaling, whereas ASCL1lo GSCs do not. Increasing ASCL1 levels in ASCL1lo GSCs restores neuronal lineage potential, promotes terminal differentiation, and attenuates tumorigenicity. ASCL1 mediates these effects by functioning as a pioneer factor at closed chromatin, opening new sites to activate a neurogenic gene expression program. Directing GSCs toward terminal differentiation may provide therapeutic applications for a subset of GBM patients and strongly supports efforts to restore differentiation potential in GBM and other cancers.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Neoplasias Encefálicas/patología , Carcinogénesis/patología , Linaje de la Célula , Cromatina/metabolismo , Glioblastoma/patología , Neuronas/patología , Secuencia de Bases , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Neoplasias Encefálicas/genética , Carcinogénesis/genética , Diferenciación Celular/genética , Progresión de la Enfermedad , Elementos de Facilitación Genéticos/genética , Regulación Neoplásica de la Expresión Génica , Glioblastoma/genética , Humanos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Neuronas/metabolismo , Regiones Promotoras Genéticas/genética , Unión Proteica , Análisis de Secuencia de ARN , Regulación hacia Arriba/genética
19.
Cancer Cell ; 29(6): 859-873, 2016 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-27300435

RESUMEN

Glioblastomas (GBM) grow in a rich neurochemical milieu, but the impact of neurochemicals on GBM growth is largely unexplored. We interrogated 680 neurochemical compounds in patient-derived GBM neural stem cells (GNS) to determine the effects on proliferation and survival. Compounds that modulate dopaminergic, serotonergic, and cholinergic signaling pathways selectively affected GNS growth. In particular, dopamine receptor D4 (DRD4) antagonists selectively inhibited GNS growth and promoted differentiation of normal neural stem cells. DRD4 antagonists inhibited the downstream effectors PDGFRß, ERK1/2, and mTOR and disrupted the autophagy-lysosomal pathway, leading to accumulation of autophagic vacuoles followed by G0/G1 arrest and apoptosis. These results demonstrate a role for neurochemical pathways in governing GBM stem cell proliferation and suggest therapeutic approaches for GBM.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Células-Madre Neurales/efectos de los fármacos , Receptores de Dopamina D4/metabolismo , Bibliotecas de Moléculas Pequeñas/administración & dosificación , Animales , Autofagia , Neoplasias Encefálicas/metabolismo , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioblastoma/metabolismo , Humanos , Ratones , Células Madre Neoplásicas/citología , Células Madre Neoplásicas/efectos de los fármacos , Células-Madre Neurales/citología , Células-Madre Neurales/patología , Receptores de Dopamina D4/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/farmacología , Análisis de Supervivencia , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Chin Med J (Engl) ; 128(10): 1293-300, 2015 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-25963347

RESUMEN

BACKGROUND: The awareness, treatment and prevention of chronic diseases are generally poor among the elderly population of China, whereas the prevention and control of chronic diseases in elderly veteran communities have been ongoing for more than 30 years. Therefore, investigating the awareness status of chronic disabling neurological diseases (CDND) and common chronic diseases (CCD) among elderly veterans may provide references for related programs among the elderly in the general population. METHODS: A cross-sectional survey was conducted among veterans ≥60 years old in veteran communities in Beijing. The awareness of preventive strategies against dementia, Alzheimer's disease (AD), Parkinson's disease (PD), sleep disorders, cerebrovascular disease (CVD) and CCD such as hypertension, and the approaches used to access this information, including media, word of mouth (verbal communication among the elderly) and health care professionals, were investigated via face-to-face interviews. RESULTS: The awareness rates for CCD and CVD were approximately 100%, but that for AD was the lowest at <10%. The awareness rates for sleep disorders, PD and dementia, were 51.0-89.4%. Media was the most commonly selected mode of communication by which veterans acquired knowledge about CCD and CVD. Media was used by approximately 80% of veterans. Both health care professionals and word of mouth were used by approximately 50% of veterans. With respect to the source of information about CDND excluding AD, the rates of the use of health care professionals, word of mouth and media were 10.6-28.2%, 56.5-76.5%, and approximately 50%, respectively. CONCLUSIONS: The awareness of CDND among elderly veterans was significantly lower than that of CCD. More information about CDND should be disseminated by health care professionals. Appropriate guidance will promote the rapid and extensive dissemination of information about the prevention of CDND by media and word-of-mouth peer education.


Asunto(s)
Enfermedad Crónica/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Enfermedades del Sistema Nervioso/prevención & control , Anciano , Anciano de 80 o más Años , Concienciación/fisiología , Estudios Transversales , Femenino , Humanos , Masculino , Veteranos/estadística & datos numéricos
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