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1.
Mol Cell ; 81(24): 4964-4978.e8, 2021 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-34687603

RESUMEN

Mammalian SWI/SNF (BAF) chromatin remodelers play dosage-sensitive roles in many human malignancies and neurologic disorders. The gene encoding the BAF subunit actin-like 6a (ACTL6A) is amplified early in the development of many squamous cell carcinomas (SCCs), but its oncogenic role remains unclear. Here we demonstrate that ACTL6A overexpression leads to its stoichiometric assembly into BAF complexes and drives their interaction and engagement with specific regulatory regions in the genome. In normal epithelial cells, ACTL6A was substoichiometric to other BAF subunits. However, increased ACTL6A levels by ectopic expression or in SCC cells led to near saturation of ACTL6A within BAF complexes. Increased ACTL6A occupancy enhanced polycomb opposition genome-wide to activate SCC genes and facilitated the co-dependent loading of BAF and TEAD-YAP complexes on chromatin. Both mechanisms appeared to be critical and function as a molecular AND gate for SCC initiation and maintenance, thereby explaining the specificity of the role of ACTL6A amplification in SCCs.


Asunto(s)
Actinas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Ensamble y Desensamble de Cromatina , Cromatina/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas del Grupo Polycomb/metabolismo , Actinas/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Cromatina/genética , Proteínas Cromosómicas no Histona/genética , Proteínas de Unión al ADN/genética , Epigénesis Genética , Amplificación de Genes , Regulación Neoplásica de la Expresión Génica , Células HEK293 , Humanos , Proteínas del Grupo Polycomb/genética , Unión Proteica , Factores de Transcripción de Dominio TEA/genética , Factores de Transcripción de Dominio TEA/metabolismo , Proteínas Señalizadoras YAP/genética , Proteínas Señalizadoras YAP/metabolismo
2.
Support Care Cancer ; 30(1): 279-287, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34273033

RESUMEN

PURPOSE: The aim of this study is to identify sources of distress among cancer patients attending rehabilitation in the community. METHODS: Participants were 430 patients recruited from a cancer rehabilitation center in Singapore between 2017 and 2018, who had rated their distress using the distress thermometer (DT) and indicated associated problems on the problem list. Chi-square tests were used to detect differences in the reported symptoms among three age groups. Exploratory factor analysis was used to identify symptom clusters. Partial correlational analysis was then performed to examine the relationship between distress, symptom clusters, and age controlling for gender and cancer type. RESULTS: About 30% of the participants reported distress ≥ 5 on the DT (mean 3.3 ± 2.5), and the mean number of problems endorsed was 8 ± 6. A higher total number of reported problems (r = .63) and younger age (r = - .21) were associated with increased distress. The younger age group also reported more problems surrounding emotions, finance, work/school, children-related issues, and physical symptoms such as sleep and nausea. Of the 12 factors identified, 9 psychosocial and physical symptom clusters correlated with distress (r ranging from .12 to .41). All results were statistically significant after adjustment (p ≤ 0.05). CONCLUSION: Younger survivors are more at risk of distress and report greater role functioning concerns related to childcare, partner relationship, and work participation. Age-tailored and multimodal interventions may be necessary to adequately address age-related differences and help coordinate management of multiple symptom clusters across physical and psychosocial concerns.


Asunto(s)
Neoplasias , Estrés Psicológico , Niño , Humanos , Náusea , Sueño , Estrés Psicológico/epidemiología , Estrés Psicológico/etiología , Escala Visual Analógica
3.
Int J Med Sci ; 9(3): 193-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22408567

RESUMEN

In recent years remarkable progress has been made towards the understanding of proposed hallmarks of cancer development and treatment. However with its increasing incidence, the clinical management of cancer continues to be a challenge for the 21st century. Treatment modalities comprise of radiation therapy, surgery, chemotherapy, immunotherapy and hormonal therapy. Radiation therapy remains an important component of cancer treatment with approximately 50% of all cancer patients receiving radiation therapy during their course of illness; it contributes towards 40% of curative treatment for cancer. The main goal of radiation therapy is to deprive cancer cells of their multiplication (cell division) potential. Celebrating a century of advances since Marie Curie won her second Nobel Prize for her research into radium, 2011 has been designated the Year of Radiation therapy in the UK. Over the last 100 years, ongoing advances in the techniques of radiation treatment and progress made in understanding the biology of cancer cell responses to radiation will endeavor to increase the survival and reduce treatment side effects for cancer patients. In this review, principles, application and advances in radiation therapy with their biological end points are discussed.


Asunto(s)
Neoplasias/radioterapia , Apoptosis/efectos de la radiación , Autofagia/efectos de la radiación , Daño del ADN , Fraccionamiento de la Dosis de Radiación , Humanos , Neoplasias/patología , Fotones/uso terapéutico , Radiocirugia , Radioterapia Conformacional , Radioterapia Guiada por Imagen , Radioterapia de Intensidad Modulada
4.
Proc Natl Acad Sci U S A ; 106(13): 5181-6, 2009 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-19279220

RESUMEN

Mammalian SWI/SNF [also called BAF (Brg/Brahma-associated factors)] ATP-dependent chromatin remodeling complexes are essential for formation of the totipotent and pluripotent cells of the early embryo. In addition, subunits of this complex have been recovered in screens for genes required for nuclear reprogramming in Xenopus and mouse embryonic stem cell (ES) morphology. However, the mechanism underlying the roles of these complexes is unclear. Here, we show that BAF complexes are required for the self-renewal and pluripotency of mouse ES cells but not for the proliferation of fibroblasts or other cells. Proteomic studies reveal that ES cells express distinctive complexes (esBAF) defined by the presence of Brg (Brahma-related gene), BAF155, and BAF60A, and the absence of Brm (Brahma), BAF170, and BAF60C. We show that this specialized subunit composition is required for ES cell maintenance and pluripotency. Our proteomic analysis also reveals that esBAF complexes interact directly with key regulators of pluripotency, suggesting that esBAF complexes are specialized to interact with ES cell-specific regulators, providing a potential explanation for the requirement of BAF complexes in pluripotency.


Asunto(s)
Proteínas Cromosómicas no Histona/fisiología , Células Madre Embrionarias/citología , Células Madre Pluripotentes/citología , Factores de Transcripción/fisiología , Animales , Proliferación Celular , Ensamble y Desensamble de Cromatina , Proteínas Cromosómicas no Histona/análisis , Fibroblastos/citología , Ratones , Proteínas Musculares/análisis , Proteómica , Factores de Transcripción/análisis
5.
Singapore Med J ; 53(6): 416-21, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22711043

RESUMEN

Nasopharyngeal cancer (NPC) is a common malignancy affecting Asian countries, especially the Chinese population. Treatment regimes and results have improved over the years with better overall survival outcome data. Radiotherapy with or without chemotherapy is successful in many patients. Local recurrences are treated with nasopharyngectomy or another course of radiotherapy. The upper cervical spine and skull base can also be involved in NPC patients. Possible aetiologies are osteoradionecrosis, chronic infection and tumour invasion. This article reviews the NPC involvement of C1-2 due to the various pathologies as well as the diagnostic and surgical treatment strategies. Three clinical cases that were surgically treated are discussed along with a review of the current literature.


Asunto(s)
Vértebras Cervicales/efectos de los fármacos , Vértebras Cervicales/efectos de la radiación , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/cirugía , Adulto , Anciano , Neoplasias Óseas/secundario , Carcinoma , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Osteomielitis/diagnóstico , Osteomielitis/etiología , Osteomielitis/cirugía , Osteorradionecrosis/etiología , Recurrencia , Fracturas de la Columna Vertebral/etiología , Resultado del Tratamiento
6.
Cancer Discov ; 2(7): 591-7, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22705984

RESUMEN

UNLABELLED: The molecular pathogenesis of natural killer/T-cell lymphoma (NKTCL) is not well understood. We conducted whole-exome sequencing and identified Janus kinase 3 (JAK3) somatic-activating mutations (A572V and A573V) in 2 of 4 patients with NKTCLs. Further validation of the prevalence of JAK3 mutations was determined by Sanger sequencing and high-resolution melt (HRM) analysis in an additional 61 cases. In total, 23 of 65 (35.4%) cases harbored JAK3 mutations. Functional characterization of the JAK3 mutations support its involvement in cytokine-independent JAK/STAT constitutive activation leading to increased cell growth. Moreover, treatment of both JAK3-mutant and wild-type NKTCL cell lines with a novel pan-JAK inhibitor, CP-690550, resulted in dose-dependent reduction of phosphorylated STAT5, reduced cell viability, and increased apoptosis. Hence, targeting the deregulated JAK/STAT pathway could be a promising therapy for patients with NKTCLs. SIGNIFICANCE: Gene mutations causing NKTCL have not been fully identified. Through exome sequencing, we identified activating mutations of JAK3 that may play a significant role in the pathogenesis of NKTCLs. Our findings have important implications for the management of patients with NKTCLs.


Asunto(s)
Janus Quinasa 3/genética , Linfoma de Células T/genética , Mutación , Células T Asesinas Naturales/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Western Blotting , Línea Celular Tumoral , Proliferación Celular , Análisis Mutacional de ADN , Activación Enzimática/genética , Femenino , Humanos , Janus Quinasa 3/antagonistas & inhibidores , Janus Quinasa 3/metabolismo , Linfoma de Células T/metabolismo , Linfoma de Células T/patología , Masculino , Persona de Mediana Edad , Células T Asesinas Naturales/patología , Fosforilación , Piperidinas , Pirimidinas/farmacología , Pirroles/farmacología , Interferencia de ARN , Factor de Transcripción STAT5/metabolismo
7.
Psychol Assess ; 23(2): 558-62, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21319906

RESUMEN

Reverse-scored items on assessment scales increase cognitive processing demands and may therefore lead to measurement problems for older adult respondents. In this study, the objective was to examine possible psychometric inadequacies of reverse-scored items on the Center for Epidemiologic Studies Depression Scale (CES-D) when used to assess ethnically diverse older adults. Using baseline data from a gerontologic clinical trial (n = 460), we tested the hypotheses that the reversed items on the CES-D (a) are less reliable than nonreversed items, (b) disproportionately lead to intraindividually atypical responses that are psychometrically problematic, and (c) evidence improved measurement properties when an imputation procedure based on the scale mean is used to replace atypical responses. In general, the results supported the hypotheses. Relative to nonreversed CES-D items, the 4 reversed items were less internally consistent, were associated with lower item-scale correlations, and were more often answered atypically at an intraindividual level. Further, the atypical responses were negatively correlated with responses to psychometrically sound nonreversed items that had similar content. The use of imputation to replace atypical responses enhanced the predictive validity of the set of reverse-scored items. Among older adult respondents, reverse-scored items are associated with measurement difficulties. It is recommended that appropriate correction procedures such as item readministration or statistical imputation be applied to reduce the difficulties.


Asunto(s)
Depresión/psicología , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Factores de Edad , Anciano , Interpretación Estadística de Datos , Depresión/diagnóstico , Etnicidad/psicología , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados
8.
Ann Acad Med Singap ; 40(2): 90-6, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21468463

RESUMEN

INTRODUCTION: Our study investigates whether an approximation of breast cancer molecular subtypes using the hormone receptors and HER-2 status prognosticates for disease control after breast conservation therapy (BCT) in node-negative Asian breast cancer patients. METHODS AND MATERIALS: We retrospectively reviewed 541 women with node-negative breast cancers treated with BCT between 1989 and 2007. Hormone receptors and HER-2 status were obtained from patients' histological report. All patients received radiotherapy. Thirty-six percent and 68% of women received chemotherapy and hormonal treatment respectively. RESULTS: Median follow-up of patients is 72 months. Five-year local recurrence free survival (LRFS) is 97.2% for the cohort but differs between subtypes: luminal A, 0.8%; luminal B, 1.4%; HER-2, 3.6% and basal-like, 12.7% (P = 0.047). The 5-year distant disease free survival (DDFS) is 96.4% for the cohort but differs between subtypes: luminal A, 98.2%; luminal B, 92.6%; HER-2, 89.5% and basal-like, 91.5% (P = 0.019). The 5-year disease free survival (DFS) is 94.4% for the cohort but differs between subtypes: luminal A, 97.4%; luminal B, 92.7%; HER-2, 86.3% and basal-like, 85.0% (P = 0.007). Univariate analysis with luminal A as baseline revealed an association of the other 3 subtypes with decreased DFS (P = 0.007), Hazard Ratio (HR) of 2.2, 4.4 and 3.3 to Luminal B, HER-2 and basal subtypes, respectively. On multivariate analysis, HER-2 subtype (AHR = 3.3, 95% CI, 1.1 to 9.8, P = 0.036) and basal-like subtype (HR = 3.5, 95% CI, 1.2 to 9.9, P = 0.019) prognosticate adversely for DFS. CONCLUSION: The combination of hormone receptors and HER-2 status can be used as surrogates for molecular subtypes in Asian breast cancer patients with node-negative disease to prognosticate LRFS, DFS and DDFS.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Receptor ErbB-2/genética , Receptores de Estrógenos/genética , Receptores de Progesterona/genética , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/prevención & control , Femenino , Humanos , Mastectomía Segmentaria , Persona de Mediana Edad , Análisis Multivariante , Recurrencia Local de Neoplasia , Pronóstico , Radioterapia Adyuvante , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento
9.
J Immunol ; 178(7): 4315-21, 2007 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-17371988

RESUMEN

TCR signals induce the nuclear localization of NFATc proteins, which are removed from the nucleus after rephosphorylation by glycogen synthase kinase 3 and other kinases. Rapid nuclear export might allow continuous monitoring of receptor occupancy, making the transcriptional response proportional to the duration of TCR/CD28 signaling. To investigate this possibility, we analyzed mice in which T cells express a NFATc1 variant (NFATc1(nuc)) with serine-to-alanine changes at the glycogen synthase kinase 3 phosphorylation sites. NFATc1(nuc) T cells have constitutively nuclear NFATc1, enhanced T cell activation in vivo, and calcineurin-independent proliferation in vitro. NFATc1(nuc) T cells are hypersensitive to TCR/CD3 stimulation, resulting in enhanced proliferation and cytokine production that is independent of CD28 costimulation. These results support the notion that CD28 inhibits nuclear export of NFATc transcription factors. In addition, NFATc1(nuc) destabilizes a positive feedback loop in which NFATc1 activates its own transcription as well as its targets, such as CD40 ligand and Th1/Th2 cytokines.


Asunto(s)
Antígenos CD28/inmunología , Activación de Linfocitos , Factores de Transcripción NFATC/metabolismo , Linfocitos T/inmunología , Transporte Activo de Núcleo Celular , Alanina/genética , Alanina/metabolismo , Sustitución de Aminoácidos , Animales , Núcleo Celular/química , Núcleo Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Ciclosporina/farmacología , Citocinas/metabolismo , Femenino , Glucógeno Sintasa Quinasa 3/metabolismo , Masculino , Ratones , Factores de Transcripción NFATC/análisis , Factores de Transcripción NFATC/genética , Fosforilación , Receptores de Antígenos de Linfocitos T/agonistas , Receptores de Antígenos de Linfocitos T/inmunología , Serina/genética , Serina/metabolismo , Células TH1/inmunología , Células Th2/inmunología
10.
Genes Dev ; 16(19): 2509-17, 2002 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-12368262

RESUMEN

A variety of chromatin remodeling complexes are thought to assist sequence-specific transcription factors. The complexes described to date are expressed ubiquitously, suggesting that they have general transcriptional functions. We show that vertebrate neurons have a specialized chromatin remodeling complex, bBAF, specifically containing the actin-related protein, BAF53b, which is first expressed in postmitotic neurons at about murine embryonic day 12.5 (E12.5). BAF53b is combinatorially assembled into polymorphic complexes with ubiquitous subunits including the two ATPases BRG1 and BRM. We speculate that bBAF complexes create neuronal-specific patterns of chromatin accessibility, thereby imparting new regulatory characteristics to ubiquitous sequence-specific transcription factors in neurons.


Asunto(s)
Actinas/metabolismo , Encéfalo/metabolismo , Cromatina/fisiología , Proteínas Cromosómicas no Histona , Proteínas de Unión al ADN/metabolismo , Secuencia de Aminoácidos , Animales , ADN Helicasas , Expresión Génica , Células HeLa , Humanos , Ratones , Datos de Secuencia Molecular , Neuronas/metabolismo , Proteínas Nucleares/metabolismo , Polimorfismo Genético , Homología de Secuencia de Aminoácido , Factores de Transcripción/metabolismo
11.
Cell ; 118(5): 649-63, 2004 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-15339668

RESUMEN

The delicate leaflets that make up vertebrate heart valves are essential for our moment-to-moment existence. Abnormalities of valve formation are the most common serious human congenital defect. Despite their importance, relatively little is known about valve development. We show that the initiation of heart valve morphogenesis in mice requires calcineurin/NFAT to repress VEGF expression in the myocardium underlying the site of prospective valve formation. This repression of VEGF at E9 is essential for endocardial cells to transform into mesenchymal cells. Later, at E11, a second wave of calcineurin/NFAT signaling is required in the endocardium, adjacent to the earlier myocardial site of NFAT action, to direct valvular elongation and refinement. Thus, NFAT signaling functions sequentially from myocardium to endocardium within a valvular morphogenetic field to initiate and perpetuate embryonic valve formation. This mechanism also operates in zebrafish, indicating a conserved role for calcineurin/NFAT signaling in vertebrate heart valve morphogenesis.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Endocardio/embriología , Endocardio/metabolismo , Válvulas Cardíacas/embriología , Miocardio/metabolismo , Proteínas Nucleares , Factores de Transcripción/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Calcineurina/metabolismo , Diferenciación Celular/genética , Células Cultivadas , Proteínas de Unión al ADN/genética , Embrión no Mamífero , Endocardio/citología , Regulación del Desarrollo de la Expresión Génica/genética , Válvulas Cardíacas/citología , Válvulas Cardíacas/metabolismo , Mesodermo/citología , Mesodermo/metabolismo , Ratones , Ratones Transgénicos , Morfogénesis/genética , Miocardio/citología , Factores de Transcripción NFATC , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Transducción de Señal/genética , Factores de Transcripción/genética , Pez Cebra
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