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1.
Arch Dis Child ; 109(2): 130-137, 2024 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-38041663

RESUMEN

OBJECTIVE: To compare and contrast the perceived care needs of children with life-limiting conditions (CLLC) from the perspectives of the children, parents and healthcare providers. DESIGN: A qualitative case study method using semistructured interviews was employed with a within-case and across-case analysis. Themes and subthemes emerging from the cases were compared and contrasted in the across-case analysis to explore the similarities and variations in participant perceptions. SETTING/PARTICIPANTS: The setting was the paediatric departments of five regional hospitals in Hong Kong. Twenty-five sets of informants (CLLC-parent-healthcare provider) were recruited, with 65 individual interviews conducted. RESULTS: A total of 3784 units of analysis were identified, resulting in three themes with subthemes. 'Living with the disease' (55.8%) occupied the largest proportion, followed by 'information and understanding about the disease' (27.4%), and 'care support and palliative care' (16.8%). Healthcare provider support mainly focused on physical concerns. Family and social support were present, but carer stress created tension between couples. Doctors were the primary source of medical information, but the parents had to seek further information via the internet and support from patient groups. There was a perceived need for better coordination and collaboration of care. The palliative care approach coordinated by nurses was seen as helpful in addressing the care needs of the CLLC. CONCLUSIONS: This original study identified the importance of palliative care with active engagement of parents which can address the service gap for CLLC.


Asunto(s)
Cuidados Paliativos , Padres , Niño , Humanos , Hong Kong , Apoyo Social , Investigación Cualitativa
2.
Nat Commun ; 13(1): 2965, 2022 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-35618699

RESUMEN

Development of the gastrointestinal system occurs after gut tube closure, guided by spatial and temporal control of gene expression. However, it remains unclear what forces regulate these spatiotemporal gene expression patterns. Here we perform single-cell chromatin profiling of the primitive gut tube to reveal organ-specific chromatin patterns that reflect the anatomical patterns of distinct organs. We generate a comprehensive map of epigenomic changes throughout gut development, demonstrating that dynamic chromatin accessibility patterns associate with lineage-specific transcription factor binding events to regulate organ-specific gene expression. Additionally, we show that loss of Sox2 and Cdx2, foregut and hindgut lineage-specific transcription factors, respectively, leads to fate shifts in epigenomic patterns, linking transcription factor binding, chromatin accessibility, and lineage fate decisions in gut development. Notably, abnormal expression of Sox2 in the pancreas and intestine impairs lineage fate decisions in both development and adult homeostasis. Together, our findings define the chromatin and transcriptional mechanisms of organ identity and lineage plasticity in development and adult homeostasis.


Asunto(s)
Cromatina , Gástrula , Adulto , Cromatina/genética , Endodermo , Epigenómica , Humanos , Factores de Transcripción
3.
Pediatr Pulmonol ; 57(7): 1799-1801, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35419994

RESUMEN

INTRODUCTION: Spinal muscular atrophy is a congenital condition associated with mutations in the SMN1 gene. Patients have normal intellectual development, but the natural history is progressive respiratory failure resulting in premature death. CASE: Diagnosed with spinal muscular atrophy type 2 in early primary school, the wheelchair-bound girl developed severe pneumonia on one occasion, when she became critically ill and was admitted to the paediatric intensive care unit with multiorgan dysfunction, requiring mechanical ventilation and high inotropic support. Parents and the patient expressed strong desire for full respiratory and intensive care support to be given. Survived the episode, she is wheelchair ambulatory and continues to pursue a creative artistic career. DISCUSSION: Children with SMA and their families need to be supported by a comprehensive multi-disciplinary team to manage this illness. Pediatricians and healthcare givers must provide up-to-date health advice on COVID-19 prophylaxis and management to special groups of patients with respiratory and neurological risks.


Asunto(s)
COVID-19 , Atrofia Muscular Espinal , Insuficiencia Respiratoria , Atrofias Musculares Espinales de la Infancia , Niño , Cuidados Críticos , Femenino , Humanos , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/terapia , Atrofias Musculares Espinales de la Infancia/complicaciones , Atrofias Musculares Espinales de la Infancia/terapia
4.
Catheter Cardiovasc Interv ; 99(3): 583-592, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34478233

RESUMEN

OBJECTIVES: To compare clinical outcomes in high bleeding risk (HBR) patients with and without complex percutaneous coronary intervention (PCI) treated with Resolute Onyx zotarolimus-eluting stents (ZES) after 1-month dual antiplatelet therapy (DAPT). BACKGROUND: PCI with 1-month DAPT has been demonstrated to be safe in HBR patients treated with Resolute Onyx ZES. Whether these outcomes are consistent in patients with complex lesions is uncertain. METHODS: Among HBR patients who were event-free 1 month after PCI with ZES and treated thereafter with single antiplatelet therapy (SAPT), the clinical outcomes between 1 month and 1 year were compared after complex PCI (3 vessels treated, ≥ 3 lesions treated, total stent length > 60 mm, bifurcation with ≥ 2 stents implanted, atherectomy, or left main, surgical bypass graft or chronic total occlusion PCI) versus noncomplex PCI. Propensity score adjustment was performed to adjust for baseline differences among complex and noncomplex patients. RESULTS: Complex patients (N = 401, 26.6% of total) had a higher prevalence of hyperlipidemia, diabetes mellitus and previous myocardial infarction (MI). Between 1 month and 1 year, rates of MI (7.1% vs. 4.0%, p = 0.02) and cardiac death/MI (9.3% vs. 6.1%, p = 0.04) were higher among complex versus noncomplex patients, although stent thrombosis rates were similar. After adjustment for baseline characteristics, differences in outcomes were no longer significant between groups. CONCLUSIONS: Higher rates of ischemic outcomes in complex PCI patients were largely explained by baseline clinical differences, rather than lesion complexity, among HBR patients treated with 1-month DAPT following PCI with Resolute Onyx ZES.


Asunto(s)
Enfermedad de la Arteria Coronaria , Stents Liberadores de Fármacos , Intervención Coronaria Percutánea , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Enfermedad de la Arteria Coronaria/terapia , Stents Liberadores de Fármacos/efectos adversos , Terapia Antiplaquetaria Doble/efectos adversos , Humanos , Intervención Coronaria Percutánea/efectos adversos , Inhibidores de Agregación Plaquetaria , Resultado del Tratamiento
5.
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
6.
Ear Nose Throat J ; 100(3_suppl): 204S-206S, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33459563

RESUMEN

Mechanical feedback is one of the most common difficulties encountered when fitting hearing aids for toddlers and young children. We described the use of 3D printing to tailor a protective cap for a toddler with bilateral microtia/canal atresia to facilitate bone-anchoring hearing aid use.


Asunto(s)
Audífonos , Pérdida Auditiva Conductiva/rehabilitación , Impresión Tridimensional , Ajuste de Prótesis/instrumentación , Equipos de Seguridad , Conducción Ósea , Preescolar , Microtia Congénita/rehabilitación , Conducto Auditivo Externo/anomalías , Diseño de Equipo , Femenino , Pérdida Auditiva Conductiva/congénito , Humanos , Ilustración Médica , Prótesis e Implantes
7.
Nat Cancer ; 2(2): 157-173, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-35122077

RESUMEN

Glioblastomas harbor diverse cell populations, including rare glioblastoma stem cells (GSCs) that drive tumorigenesis. To characterize functional diversity within this population, we performed single-cell RNA sequencing on >69,000 GSCs cultured from the tumors of 26 patients. We observed a high degree of inter- and intra-GSC transcriptional heterogeneity that could not be fully explained by DNA somatic alterations. Instead, we found that GSCs mapped along a transcriptional gradient spanning two cellular states reminiscent of normal neural development and inflammatory wound response. Genome-wide CRISPR-Cas9 dropout screens independently recapitulated this observation, with each state characterized by unique essential genes. Further single-cell RNA sequencing of >56,000 malignant cells from primary tumors found that the majority organize along an orthogonal astrocyte maturation gradient yet retain expression of founder GSC transcriptional programs. We propose that glioblastomas grow out of a fundamental GSC-based neural wound response transcriptional program, which is a promising target for new therapy development.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/genética , Carcinogénesis/genética , Glioblastoma/genética , Humanos , Células Madre Neoplásicas/metabolismo
8.
Circ Cardiovasc Interv ; 13(11): e009565, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33167705

RESUMEN

BACKGROUND: Despite treatment guidance endorsing shortened dual antiplatelet therapy (DAPT) duration in high bleeding risk (HBR) patients after drug-eluting stents, limited evidence exists to support these recommendations. The present study was designed to examine the safety and effectiveness of 1-month DAPT duration following percutaneous coronary intervention with zotarolimus-eluting stents in HBR patients. METHODS: Onyx ONE Clear was a prospective, multicenter, nonrandomized study evaluating the safety and effectiveness of 1-month DAPT followed by single antiplatelet therapy in HBR patients undergoing percutaneous coronary intervention with Resolute Onyx drug-eluting stents. The primary analysis of cardiac death or myocardial infarction between 1 month and 1 year was performed in the prespecified one-month clear population of patients pooled from the Onyx ONE US/Japan study and Onyx ONE randomized controlled trial. One-month clear was defined as DAPT adherence and without major adverse events during the first month following percutaneous coronary intervention. RESULTS: Among patients enrolled in Onyx ONE US/Japan (n=752) and Onyx ONE randomized controlled trial (n=1018), 1506 patients fulfilled one-month clear criteria. Mean HBR characteristics per patient was 1.6 with 44.7% having multiple risks. By 2 months and 1 year, respectively, 96.9% and 89.3% of patients were taking single antiplatelet therapy. Between 1 month and 1 year, the rate of the primary end point was 7.0%. The 1-sided upper 97.5% CI was 8.4%, less than the performance goal of 9.7% (P<0.001). CONCLUSIONS: Among HBR patients who were event free before DAPT discontinuation at 1 month, favorable safety and effectiveness through 1 year support treatment with Resolute Onyx drug-eluting stents as part of an individualized strategy for shortened DAPT duration following percutaneous coronary intervention. Registration: URL: https://www.clinicaltrials.gov; Unique identifier NCT03647475.


Asunto(s)
Fármacos Cardiovasculares/administración & dosificación , Enfermedad de la Arteria Coronaria/terapia , Stents Liberadores de Fármacos , Terapia Antiplaquetaria Doble , Intervención Coronaria Percutánea/instrumentación , Inhibidores de Agregación Plaquetaria/administración & dosificación , Sirolimus/análogos & derivados , Anciano , Anciano de 80 o más Años , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/mortalidad , Esquema de Medicación , Terapia Antiplaquetaria Doble/efectos adversos , Femenino , Hemorragia/inducido químicamente , Humanos , Japón , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/mortalidad , Inhibidores de Agregación Plaquetaria/efectos adversos , Estudios Prospectivos , Diseño de Prótesis , Ensayos Clínicos Controlados Aleatorios como Asunto , Medición de Riesgo , Factores de Riesgo , Sirolimus/administración & dosificación , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
9.
Circ., cariovasc. interv. (Print) ; 13(11): 222-232, Nov. 2020. tab, graf
Artículo en Inglés | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1150552

RESUMEN

BACKGROUND: Despite treatment guidance endorsing shortened dual antiplatelet therapy (DAPT) duration in high bleeding risk (HBR) patients after drug-eluting stents, limited evidence exists to support these recommendations. The present study was designed to examine the safety and effectiveness of 1-month DAPT duration following percutaneous coronary intervention with zotarolimus-eluting stents in HBR patients. METHODS: Onyx ONE Clear was a prospective, multicenter, nonrandomized study evaluating the safety and effectiveness of 1-month DAPT followed by single antiplatelet therapy in HBR patients undergoing percutaneous coronary intervention with Resolute Onyx drug-eluting stents. The primary analysis of cardiac death or myocardial infarction between 1 month and 1 year was performed in the prespecified one-month clear population of patients pooled from the Onyx ONE US/Japan study and Onyx ONE randomized controlled trial. One-month clear was defined as DAPT adherence and without major adverse events during the first month following percutaneous coronary intervention. RESULTS: Among patients enrolled in Onyx ONE US/Japan (n=752) and Onyx ONE randomized controlled trial (n=1018), 1506 patients fulfilled one-month clear criteria. Mean HBR characteristics per patient was 1.6 with 44.7% having multiple risks. By 2 months and 1 year, respectively, 96.9% and 89.3% of patients were taking single antiplatelet therapy. Between 1 month and 1 year, the rate of the primary end point was 7.0%. The 1-sided upper 97.5% CI was 8.4%, less than the performance goal of 9.7% (P<0.001). CONCLUSIONS: Among HBR patients who were event free before DAPT discontinuation at 1 month, favorable safety and effectiveness through 1 year support treatment with Resolute Onyx drug-eluting stents as part of an individualized strategy for shortened DAPT duration following percutaneous coronary intervention.


Asunto(s)
Stents Liberadores de Fármacos , Riesgo , Intervención Coronaria Percutánea
10.
J. Am. Coll. Cardiol ; 76(17 suppl. b): 24-24, Oct., 2020. tab.
Artículo en Inglés | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1343418

RESUMEN

BACKGROUND Safety and effectiveness outcomes were examined at 1 year among high bleeding risk (HBR) patients treated with 1 month of dual antiplatelet therapy (DAPT) following PCI with zotarolimus eluting stents (ZES) (Resolute Onyx, Medtronic, Santa Rosa, Califor nia) according to lesion complexity (Table). METHODS The 1-year clinical outcomes were evaluated in HBR pa tients treated with ZES who were event-free following 1-month DAPT post-procedure with planned single antiplatelet therapy thereafter. Propensity score adjustment was performed to account for baseline differences (Table). RESULTS A total of 1,506 patients were stratified by complex (n » 395) or noncomplex (n » 1,111) PCI criteria (Table). Complex patients were more frequently men (72.2% vs. 66.1%; p » 0.03) and had higher rates of prior myocardial infarction (MI) (34.4% vs. 23.4%), prior CABG (24.1% vs. 8.9%), multivessel disease (78.2% vs. 39.8%), and B2/C lesion classification (84.2% vs. 75.6%), all p < 0.001. Complex patients had more lesions treated (1.7 vs. 1.2), longer stent length per patient (65.1 mm vs. 26.9 mm), and longer procedure time (58.8 min vs. 35.3 min), all p < 0.001. Procedural success was higher among noncomplex patients (90.8% vs. 82.0%; p < 0.001). In unadjusted analysis, the rate of MI was higher in patients with complex lesions (p » 0.04). How ever, no significant differences in any outcomes between patients with and without complex lesions were present after propensity score adjustment (Table). CONCLUSION Despite greater anatomic and procedural complexity, similar safety and effectiveness were observed in complex and noncomplex patients treated with 1-month DAPT following PCI with Resolute Onyx ZES after propensity score adjustment. These findings support 1-month DAPT among selected HBR patients undergoing PCI with Resolute Onyx ZES irrespective of lesion and procedural complexity.


Asunto(s)
Stents , Infarto del Miocardio
11.
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
12.
J Clin Invest ; 130(6): 3069-3086, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32182224

RESUMEN

Glioblastoma multiforme (GBM) contains a subpopulation of cells, GBM stem cells (GSCs), that maintain the bulk tumor and represent a key therapeutic target. Norrin is a Wnt ligand that binds Frizzled class receptor 4 (FZD4) to activate canonical Wnt signaling. Although Norrin, encoded by NDP, has a well-described role in vascular development, its function in human tumorigenesis is largely unexplored. Here, we show that NDP expression is enriched in neurological cancers, including GBM, and its levels positively correlated with survival in a GBM subtype defined by low expression of ASCL1, a proneural factor. We investigated the function of Norrin and FZD4 in GSCs and found that it mediated opposing tumor-suppressive and -promoting effects on ASCL1lo and ASCL1hi GSCs. Consistent with a potential tumor-suppressive effect of Norrin suggested by the tumor outcome data, we found that Norrin signaling through FZD4 inhibited growth in ASCL1lo GSCs. In contrast, in ASCL1hi GSCs Norrin promoted Notch signaling, independently of WNT, to promote tumor progression. Forced ASCL1 expression reversed the tumor-suppressive effects of Norrin in ASCL1lo GSCs. Our results identify Norrin as a modulator of human brain cancer progression and reveal an unanticipated Notch-mediated function of Norrin in regulating cancer stem cell biology. This study identifies an unanticipated role of Norrin in human brain cancer progression. In addition, we provide preclinical evidence suggesting Norrin and canonical Wnt signaling as potential therapeutic targets for GBM subtype-restricted cancer stem cells.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Proteínas del Ojo/metabolismo , Glioblastoma/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Receptores Notch/metabolismo , Proteínas Wnt/metabolismo , Vía de Señalización Wnt , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Proteínas del Ojo/genética , Glioblastoma/genética , Glioblastoma/patología , Humanos , Proteínas de Neoplasias/genética , Proteínas del Tejido Nervioso/genética , Receptores Notch/genética , Proteínas Wnt/genética
13.
Genes Dev ; 33(9-10): 498-510, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30842215

RESUMEN

Developmental signal transduction pathways act diversely, with context-dependent roles across systems and disease types. Glioblastomas (GBMs), which are the poorest prognosis primary brain cancers, strongly resemble developmental systems, but these growth processes have not been exploited therapeutically, likely in part due to the extreme cellular and genetic heterogeneity observed in these tumors. The role of Wnt/ßcatenin signaling in GBM stem cell (GSC) renewal and fate decisions remains controversial. Here, we report context-specific actions of Wnt/ßcatenin signaling in directing cellular fate specification and renewal. A subset of primary GBM-derived stem cells requires Wnt proteins for self-renewal, and this subset specifically relies on Wnt/ßcatenin signaling for enhanced tumor burden in xenograft models. In an orthotopic Wnt reporter model, Wnthi GBM cells (which exhibit high levels of ßcatenin signaling) are a faster-cycling, highly self-renewing stem cell pool. In contrast, Wntlo cells (with low levels of signaling) are slower cycling and have decreased self-renewing potential. Dual inhibition of Wnt/ßcatenin and Notch signaling in GSCs that express high levels of the proneural transcription factor ASCL1 leads to robust neuronal differentiation and inhibits clonogenic potential. Our work identifies new contexts for Wnt modulation for targeting stem cell differentiation and self-renewal in GBM heterogeneity, which deserve further exploration therapeutically.


Asunto(s)
Diferenciación Celular/genética , Células Madre Neoplásicas/citología , Transducción de Señal , Línea Celular Tumoral , Autorrenovación de las Células/genética , Regulación Neoplásica de la Expresión Génica/genética , Glioblastoma/fisiopatología , Humanos , Receptores Notch/genética , Receptores Notch/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo
15.
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
16.
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
17.
Lab Chip ; 17(3): 511-520, 2017 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-28092382

RESUMEN

There is a growing awareness that complex 3-dimensional (3D) organs are not well represented by monolayers of a single cell type - the standard format for many drug screens. To address this deficiency, and with the goal of improving screens so that drugs with good efficacy and low toxicity can be identified, microphysiological systems (MPS) are being developed that better capture the complexity of in vivo physiology. We have previously described an organ-on-a-chip platform that incorporates perfused microvessels, such that survival of the surrounding tissue is entirely dependent on delivery of nutrients through the vessels. Here we describe an arrayed version of the platform that incorporates multiple vascularized micro-organs (VMOs) on a 96-well plate. Each VMO is independently-addressable and flow through the micro-organ is driven by hydrostatic pressure. The platform is easy to use, requires no external pumps or valves, and is highly reproducible. As a proof-of-concept we have created arrayed vascularized micro tumors (VMTs) and used these in a blinded screen to assay a small library of compounds, including FDA-approved anti-cancer drugs, and successfully identified both anti-angiogenic and anti-tumor drugs. This 3D platform is suitable for efficacy/toxicity screening against multiple tissues in a more physiological environment than previously possible.


Asunto(s)
Técnicas de Cultivo de Célula/instrumentación , Evaluación Preclínica de Medicamentos/instrumentación , Técnicas Analíticas Microfluídicas/instrumentación , Análisis de Matrices Tisulares/instrumentación , Antineoplásicos/farmacología , Evaluación Preclínica de Medicamentos/métodos , Diseño de Equipo , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Neoplasias Experimentales/metabolismo , Neovascularización Patológica/metabolismo , Análisis de Matrices Tisulares/métodos
18.
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
19.
Cancer Cell ; 28(6): 715-729, 2015 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-26626085

RESUMEN

Mutations in the histone 3 variant H3.3 have been identified in one-third of pediatric glioblastomas (GBMs), but not in adult tumors. Here we show that H3.3 is a dynamic determinant of functional properties in adult GBM. H3.3 is repressed by mixed lineage leukemia 5 (MLL5) in self-renewing GBM cells. MLL5 is a global epigenetic repressor that orchestrates reorganization of chromatin structure by punctuating chromosomes with foci of compacted chromatin, favoring tumorigenic and self-renewing properties. Conversely, H3.3 antagonizes self-renewal and promotes differentiation. We exploited these epigenetic states to rationally identify two small molecules that effectively curb cancer stem cell properties in a preclinical model. Our work uncovers a role for MLL5 and H3.3 in maintaining self-renewal hierarchies in adult GBM.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Autorrenovación de las Células , Ensamble y Desensamble de Cromatina , Proteínas de Unión al ADN/metabolismo , Glioblastoma/metabolismo , Histonas/metabolismo , Células Madre Neoplásicas/metabolismo , Adolescente , Adulto , Animales , Antineoplásicos/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Diferenciación Celular , Proliferación Celular , Autorrenovación de las Células/efectos de los fármacos , Niño , Preescolar , Ensamble y Desensamble de Cromatina/efectos de los fármacos , Metilación de ADN , Proteínas de Unión al ADN/genética , Diseño de Fármacos , Epigénesis Genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/mortalidad , Glioblastoma/patología , Histonas/genética , Humanos , Estimación de Kaplan-Meier , Ratones Endogámicos NOD , Ratones SCID , Terapia Molecular Dirigida , Mutación , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/patología , Pronóstico , Interferencia de ARN , Transducción de Señal , Factores de Tiempo , Transfección , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto , Adulto Joven
20.
J Am Soc Hypertens ; 9(10): 769-779, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26362830

RESUMEN

SYMPLICITY HTN-3, the first trial of renal denervation (RDN) versus sham, enrolled 26% African Americans, a prospectively stratified cohort. Although the 6-month systolic blood pressure (SBP) reduction in African Americans (AAs) was similar in the RDN group (-15.5 ± 25.4 mm Hg, n = 85 vs. -17.8 ± 29.2, n = 49, P = .641), the sham SBP response was 9.2 mm Hg greater (P = .057) in AAs than non-AAs. In multivariate analyses, sham SBP response was predicted by an interaction between AA and a complex antihypertensive regimen (at least one antihypertensive medication prescribed ≥3 times daily), while in the RDN group, SBP response was predicted by an interaction between AA race and baseline BP ≥ 180 mm Hg. AA race did not independently predict SBP response in either sham or RDN. There appears to be effect modification by race with individual-level patient characteristics in both treatment arms that affect the observed pattern of SBP responses.


Asunto(s)
Hipertensión/fisiopatología , Hipertensión/cirugía , Riñón/inervación , Sistema Nervioso Simpático/cirugía , Adulto , Negro o Afroamericano , Anciano , Antihipertensivos/uso terapéutico , Monitoreo Ambulatorio de la Presión Arterial , Ablación por Catéter , Estudios de Cohortes , Femenino , Humanos , Hipertensión/etnología , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , Simpatectomía/métodos , Resultado del Tratamiento
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