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1.
CA Cancer J Clin ; 74(4): 383-396, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38703384

RESUMEN

Cancer mortality rates have declined during the last 28 years, but that process is not equitably shared. Disparities in cancer outcomes by race, ethnicity, socioeconomic status, sexual orientation and gender identity, and geographic location persist across the cancer care continuum. Consequently, community outreach and engagement (COE) efforts within National Cancer Institute-Designated Cancer Center (NCI-DCC) catchment areas have intensified during the last 10 years as has the emphasis on COE and catchment areas in NCI's Cancer Center Support Grant applications. This review article attempts to provide a historic perspective of COE within NCI-DCCs. Improving COE has long been an important initiative for the NCI, but it was not until 2012 and 2016 that NCI-DCCs were required to define their catchment areas rigorously and to provide specific descriptions of COE interventions, respectively. NCI-DCCs had previously lacked adequate focus on the inclusion of historically marginalized patients in cancer innovation efforts. Integrating COE efforts throughout the research and operational aspects of the cancer centers, at both the patient and community levels, will expand the footprint of COE efforts within NCI-DCCs. Achieving this change requires sustained commitment by the centers to adjust their activities and improve access and outcomes for historically marginalized communities.


Asunto(s)
Instituciones Oncológicas , Relaciones Comunidad-Institución , National Cancer Institute (U.S.) , Neoplasias , Humanos , Estados Unidos/epidemiología , Neoplasias/terapia , Neoplasias/epidemiología , Instituciones Oncológicas/organización & administración , Disparidades en Atención de Salud
2.
Blood ; 143(11): 967-970, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38289232

RESUMEN

ABSTRACT: The root cause of sickle cell anemia has been known for 7 decades, yet no curative therapies have been available other than allogeneic bone marrow transplantation, for which applicability is limited. Two potentially curative therapies based on gene therapy and gene editing strategies have recently received US Food and Drug Administration approval. This review surveys the nature of these therapies and the opportunities and issues raised by the prospect of definitive genetically based therapies being available in clinical practice.


Asunto(s)
Anemia de Células Falciformes , Trasplante de Células Madre Hematopoyéticas , Humanos , Anemia de Células Falciformes/genética , Anemia de Células Falciformes/terapia , Trasplante de Médula Ósea , Edición Génica , Terapia Genética/métodos
3.
J Biol Chem ; 297(3): 101051, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34364872

RESUMEN

The asymmetric cell division of stem or progenitor cells generates daughter cells with distinct fates that balance proliferation and differentiation. Asymmetric segregation of Notch signaling regulatory protein Numb plays a crucial role in cell diversification. However, the molecular mechanism remains unclear. Here, we examined the unequal distribution of Numb in the daughter cells of murine erythroleukemia cells (MELCs) that undergo DMSO-induced erythroid differentiation. In contrast to the cytoplasmic localization of Numb during uninduced cell division, Numb is concentrated at the cell boundary in interphase, near the one-spindle pole in metaphase, and is unequally distributed to one daughter cell in anaphase in induced cells. The inheritance of Numb guides this daughter cell toward erythroid differentiation while the other cell remains a progenitor cell. Mitotic spindle orientation, critical for distribution of cell fate determinants, requires complex communication between the spindle microtubules and the cell cortex mediated by the NuMA-LGN-dynein/dynactin complex. Depletion of each individual member of the complex randomizes the position of Numb relative to the mitotic spindle. Gene replacement confirms that multifunctional erythrocyte protein 4.1R (4.1R) functions as a member of the NuMA-LGN-dynein/dynactin complex and is necessary for regulating spindle orientation, in which interaction between 4.1R and NuMA plays an important role. These results suggest that mispositioning of Numb is the result of spindle misorientation. Finally, disruption of the 4.1R-NuMA-LGN complex increases Notch signaling and decreases the erythroblast population. Together, our results identify a critical role for 4.1R in regulating the asymmetric segregation of Numb to mediate erythropoiesis.


Asunto(s)
División Celular Asimétrica , Células Eritroides/citología , Células Eritroides/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de Microfilamentos/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Animales , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Diferenciación Celular , Línea Celular Tumoral , Complejo Dinactina/genética , Complejo Dinactina/metabolismo , Dineínas/genética , Dineínas/metabolismo , Proteínas de la Membrana/genética , Ratones , Proteínas de Microfilamentos/genética , Mitosis , Proteínas del Tejido Nervioso/genética , Unión Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Huso Acromático/genética , Huso Acromático/metabolismo
4.
J Biol Chem ; 295(1): 191-211, 2020 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-31776189

RESUMEN

Epithelial adherens junctions (AJs) and tight junctions (TJs) undergo disassembly and reassembly during morphogenesis and pathological states. The membrane-cytoskeleton interface plays a crucial role in junctional reorganization. Protein 4.1R (4.1R), expressed as a diverse array of spliceoforms, has been implicated in linking the AJ and TJ complex to the cytoskeleton. However, which specific 4.1 isoform(s) participate and the mechanisms involved in junctional stability or remodeling remain unclear. We now describe a role for epithelial-specific isoforms containing exon 17b and excluding exon 16 4.1R (4.1R+17b) in AJs. 4.1R+17b is exclusively co-localized with the AJs. 4.1R+17b binds to the armadillo repeats 1-2 of ß-catenin via its membrane-binding domain. This complex is linked to the actin cytoskeleton via a bispecific interaction with an exon 17b-encoded peptide. Exon 17b peptides also promote fodrin-actin complex formation. Expression of 4.1R+17b forms does not disrupt the junctional cytoskeleton and AJs during the steady-state or calcium-dependent AJ reassembly. Overexpression of 4.1R-17b forms, which displace the endogenous 4.1R+17b forms at the AJs, as well as depletion of the 4.1R+17b forms both decrease junctional actin and attenuate the recruitment of spectrin to the AJs and also reduce E-cadherin during the initial junctional formation of the AJ reassembly process. Expressing 4.1R+17b forms in depleted cells rescues junctional localization of actin, spectrin, and E-cadherin assembly at the AJs. Together, our results identify a critical role for 4.1R+17b forms in AJ assembly and offer additional insights into the spectrin-actin-4.1R-based membrane skeleton as an emerging regulator of epithelial integrity and remodeling.


Asunto(s)
Uniones Adherentes/metabolismo , Proteínas del Citoesqueleto/metabolismo , Proteínas de la Membrana/metabolismo , Actinas/metabolismo , Empalme Alternativo , Animales , Sitios de Unión , Cadherinas/metabolismo , Calcio/metabolismo , Proteínas Portadoras/metabolismo , Proteínas del Citoesqueleto/genética , Perros , Humanos , Células de Riñón Canino Madin Darby , Proteínas de la Membrana/genética , Proteínas de Microfilamentos/metabolismo , Unión Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Espectrina/metabolismo , beta Catenina/química , beta Catenina/metabolismo
6.
J Biol Chem ; 291(49): 25591-25607, 2016 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-27780863

RESUMEN

Protein 4.1R (4.1R) isoforms are expressed in both cardiac and skeletal muscle. 4.1R is a component of the contractile apparatus. It is also associated with dystrophin at the sarcolemma in skeletal myofibers. However, the expression and function of 4.1R during myogenesis have not been characterized. We now report that 4.1R expression increases during C2C12 myoblast differentiation into myotubes. Depletion of 4.1R impairs skeletal muscle differentiation and is accompanied by a decrease in the levels of myosin heavy and light chains and caveolin-3. Furthermore, the expression of myogenin at the protein, but not mRNA, level is drastically decreased in 4.1R knockdown myocytes. Similar results were obtained using MyoD-induced differentiation of 4.1R-/- mouse embryonic fibroblast cells. von Hippel-Lindau (VHL) protein is known to destabilize myogenin via the ubiquitin-proteasome pathway. We show that 4.1R associates with VHL and, when overexpressed, reverses myogenin ubiquitination and stability. This suggests that 4.1R may influence myogenesis by preventing VHL-mediated myogenin degradation. Together, our results define a novel biological function for 4.1R in muscle differentiation and provide a molecular mechanism by which 4.1R promotes myogenic differentiation.


Asunto(s)
Diferenciación Celular/fisiología , Proteínas del Citoesqueleto/metabolismo , Proteínas de la Membrana/metabolismo , Mioblastos Esqueléticos/metabolismo , Miogenina/metabolismo , Proteolisis , Animales , Línea Celular , Proteínas del Citoesqueleto/genética , Proteínas de la Membrana/genética , Ratones , Ratones Noqueados , Proteína MioD/genética , Proteína MioD/metabolismo , Miogenina/genética , Estabilidad Proteica , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo
7.
Trans Am Clin Climatol Assoc ; 128: 275-297, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28790513

RESUMEN

Cancer is not a single disease. The term refers to literally hundreds of illnesses sharing common features: inappropriate proliferation of imperfectly differentiated cell types, invasion of nearby vital structures, and spread to distant sites (metastasis). Invasiveness and metastasis distinguish cancers from benign tumors such as fibroids and meningiomas. Yet, each type is distinct, possessed of defining morphologic, histologic, biochemical, and genomic features that have allowed oncologists to develop a nosology that guides diagnosis and therapy. Cancer is thus a complex collection of disorders. That complexity is increasing exponentially as modern technologies allow us to dissect each form in ever greater detail. The notion of curing cancer with a "magic bullet" like the polio vaccine is no more realistic than using the same wrench to fix a bicycle, a car, and an airliner just because they are all vehicles.


Asunto(s)
Investigación Biomédica , Neoplasias/etiología , Neoplasias/terapia , Regulación de la Expresión Génica , Humanos , Terapia Molecular Dirigida , Mutación , Neoplasias/genética , Neoplasias/patología , Medicina de Precisión
8.
J Natl Compr Canc Netw ; 14(7): 837-47, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27407124

RESUMEN

Key challenges facing the oncology community today include access to appropriate, high quality, patient-centered cancer care; defining and delivering high-value care; and rising costs. The National Comprehensive Cancer Network convened a Work Group composed of NCCN Member Institution cancer center directors and their delegates to examine the challenges of access, high costs, and defining and demonstrating value at the academic cancer centers. The group identified key challenges and possible solutions to addressing these issues. The findings and recommendations of the Work Group were then presented at the Value, Access, and Cost of Cancer Care Policy Summit in September 2015 and multi-stakeholder roundtable panel discussions explored these findings and recommendations along with additional items.


Asunto(s)
Atención a la Salud/métodos , Oncología Médica/normas , Neoplasias/economía , Humanos
9.
JAMA ; 322(10): 921-922, 2019 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-31393519
11.
Hematol Oncol Clin North Am ; 37(2): 245-259, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36907601

RESUMEN

Thalassemia is a heterogeneous group of inherited anemias having in common defective biosynthesis of one or more of the globin chain subunits of human hemoglobin. Their origins lie in inherited mutations that impair the expression of the affected globin genes. Their pathophysiology arises from the consequent insufficiency of hemoglobin production and the imbalance in the production of globin chains resulting in the accumulation of insoluble unpaired chains. These precipitate and damage or destroy developing erythroblasts and erythrocytes producing ineffective erythropoiesis and hemolytic anemia. Treatment of severe cases requires lifelong transfusion support with iron chelation therapy.


Asunto(s)
Talasemia , Talasemia beta , Humanos , Talasemia beta/genética , Medicina Molecular , Síndrome , Talasemia/genética , Hemoglobinas
12.
Circulation ; 124(10): 1124-31, 2011 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-21859973

RESUMEN

BACKGROUND: Human heart failure is associated with decreased cardiac voltage-gated Na+ channel current (encoded by SCN5A), and the changes have been implicated in the increased risk of sudden death in heart failure. Nevertheless, the mechanism of SCN5A downregulation is unclear. A number of human diseases are associated with alternative mRNA splicing, which has received comparatively little attention in the study of cardiac disease. Splicing factor expression profiles during human heart failure and a specific splicing pathway for SCN5A regulation were explored in this study. METHODS AND RESULTS: Gene array comparisons between normal human and heart failure tissues demonstrated that 17 splicing factors, associated with all major spliceosome components, were upregulated. Two of these splicing factors, RBM25 and LUC7L3, were elevated in human heart failure tissue and mediated truncation of SCN5A mRNA in both Jurkat cells and human embryonic stem cell-derived cardiomyocytes. RBM25/LUC7L3-mediated abnormal SCN5A mRNA splicing reduced Na+ channel current 91.1±9.3% to a range known to cause sudden death. Overexpression of either splicing factor resulted in an increase in truncated mRNA and a concomitant decrease in the full-length SCN5A transcript. CONCLUSIONS: Of the 17 mRNA splicing factors upregulated in heart failure, RBM25 and LUC7L3 were sufficient to explain the increase in truncated forms and the reduction in full-length Na+ channel transcript. Because the reduction in channels was in the range known to be associated with sudden death, interruption of this abnormal mRNA processing may reduce arrhythmic risk in heart failure.


Asunto(s)
Insuficiencia Cardíaca/genética , Empalme del ARN , Proteínas de Unión al ARN/metabolismo , Canales de Sodio/genética , Adulto , Anciano , Células Cultivadas , Regulación hacia Abajo , Células Madre Embrionarias/metabolismo , Femenino , Perfilación de la Expresión Génica , Humanos , Células Jurkat , Masculino , Persona de Mediana Edad , Miocitos Cardíacos/metabolismo , Canal de Sodio Activado por Voltaje NAV1.5 , Proteínas Nucleares , Empalmosomas/metabolismo , Regulación hacia Arriba , Adulto Joven
13.
Blood ; 114(19): 4233-42, 2009 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-19729518

RESUMEN

The tightly regulated production of distinct erythrocyte protein 4.1R isoforms involves differential splicing of 3 mutually exclusive first exons (1A, 1B, 1C) to the alternative 3' splice sites (ss) of exon 2'/2. Here, we demonstrate that exon 1 and 2'/2 splicing diversity is regulated by a transcription-coupled splicing mechanism. We also implicate distinctive regulatory elements that promote the splicing of exon 1A to the distal 3' ss and exon 1B to the proximal 3' ss in murine erythroleukemia cells. A hybrid minigene driven by cytomegalovirus promoter mimicked 1B-promoter-driven splicing patterns but differed from 1A-promoter-driven splicing patterns, suggesting that promoter identity affects exon 2'/2 splicing. Furthermore, splicing factor SF2/ASF ultraviolet (UV) cross-linked to the exon 2'/2 junction CAGAGAA, a sequence that overlaps the distal U2AF(35)-binding 3' ss. Consequently, depletion of SF2/ASF allowed exon 1B to splice to the distal 3' ss but had no effect on exon 1A splicing. These findings identify for the first time that an SF2/ASF binding site also can serve as a 3' ss in a transcript-dependent manner. Taken together, our results suggest that 4.1R gene expression involves transcriptional regulation coupled with a complex splicing regulatory network.


Asunto(s)
Empalme Alternativo , Proteínas Sanguíneas/genética , Proteínas del Citoesqueleto/genética , Proteínas de la Membrana/genética , Regiones no Traducidas 5' , Animales , Secuencia de Bases , Sitios de Unión/genética , Proteínas Sanguíneas/biosíntesis , Línea Celular , Proteínas del Citoesqueleto/biosíntesis , ADN Polimerasa II/metabolismo , Cartilla de ADN/genética , Exones , Humanos , Leucemia Eritroblástica Aguda/genética , Leucemia Eritroblástica Aguda/metabolismo , Proteínas de la Membrana/biosíntesis , Ratones , Proteínas de Microfilamentos , Modelos Genéticos , Datos de Secuencia Molecular , Proteínas Nucleares/metabolismo , Regiones Promotoras Genéticas , Isoformas de Proteínas/biosíntesis , Isoformas de Proteínas/genética , Proteínas de Unión al ARN/metabolismo , Ribonucleoproteínas/metabolismo , Factores de Empalme Serina-Arginina , Factor de Empalme U2AF , Distribución Tisular , Transcripción Genética , Activación Transcripcional , Células Tumorales Cultivadas
18.
Mol Biol Cell ; 16(1): 117-27, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15525677

RESUMEN

The nonerythrocyte isoform of the cytoskeletal protein 4.1R (4.1R) is associated with morphologically dynamic structures during cell division and has been implicated in mitotic spindle function. In this study, we define important 4.1R isoforms expressed in interphase and mitotic cells by RT-PCR and mini-cDNA library construction. Moreover, we show that 4.1R is phosphorylated by p34cdc2 kinase on residues Thr60 and Ser679 in a mitosis-specific manner. Phosphorylated 4.1R135 isoform(s) associate with tubulin and Nuclear Mitotic Apparatus protein (NuMA) in intact HeLa cells in vivo as well as with the microtubule-associated proteins in mitotic asters assembled in vitro. Recombinant 4.1R135 is readily phosphorylated in mitotic extracts and reconstitutes mitotic aster assemblies in 4.1R-immunodepleted extracts in vitro. Furthermore, phosphorylation of these residues appears to be essential for the targeting of 4.1R to the spindle poles and for mitotic microtubule aster assembly in vitro. Phosphorylation of 4.1R also enhances its association with NuMA and tubulin. Finally, we used siRNA inhibition to deplete 4.1R from HeLa cells and provide the first direct genetic evidence that 4.1R is required to efficiently focus mitotic spindle poles. Thus, we suggest that 4.1R is a member of the suite of direct cdc2 substrates that are required for the establishment of a bipolar spindle.


Asunto(s)
Proteínas del Citoesqueleto/fisiología , Proteínas de la Membrana/fisiología , Mitosis , Secuencia de Aminoácidos , Núcleo Celular/metabolismo , Proteínas del Citoesqueleto/metabolismo , Citoesqueleto/metabolismo , ADN Complementario/metabolismo , Electroforesis en Gel de Poliacrilamida , Técnica del Anticuerpo Fluorescente Indirecta , Biblioteca de Genes , Células HeLa , Humanos , Interfase , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Fenotipo , Fosforilación , Plásmidos/metabolismo , Isoformas de Proteínas , Estructura Terciaria de Proteína , ARN Interferente Pequeño/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Huso Acromático/metabolismo , Tubulina (Proteína)/metabolismo
19.
Hematol Oncol Clin North Am ; 37(2): xvii-xxi, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36907616
20.
Hematol Oncol Clin North Am ; 37(2): xiii-xv, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36907615
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