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1.
Clin Gastroenterol Hepatol ; 20(6): e1493-e1499, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34896283

RESUMEN

Immunization against the spike protein of SARS-CoV-2 reduces transmission1,2 and severe outcomes. However, little is known regarding the impact of immune-mediated diseases and immunosuppressive medications on the efficacy of vaccination. Vaccination immunity is transient, with breakthrough cases increasing at longer time intervals since the last dose.3,4 Although there are data on SARS-CoV-2 vaccine on early seroconversion in patients with inflammatory bowel disease (IBD),5 no data in the same cohort exist describing the durability of these antibodies over time. We sought to investigate the impact of IBD and its therapies on postvaccination antibody response and kinetics of immunogenicity decline, because these findings may better inform clinical guidelines and recommendations on precautions and booster vaccination.


Asunto(s)
COVID-19 , Enfermedades Inflamatorias del Intestino , Anticuerpos Antivirales/uso terapéutico , COVID-19/prevención & control , Vacunas contra la COVID-19 , Enfermedad Crónica , Humanos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , SARS-CoV-2 , Vacunación
2.
J Natl Compr Canc Netw ; 18(3): 288-296, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32135512

RESUMEN

BACKGROUND: Pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) for triple-negative breast cancer (TNBC) predicts decreased distant metastasis. However, most patients do not experience pCR, and other risk factors for distant metastasis after NAC are poorly characterized. This study investigated factors predictive of distant metastasis in TNBC without pCR after NAC. METHODS: Women with TNBC treated with NAC, surgery, and radiation therapy in 2000 through 2013 were reviewed. Freedom from distant metastasis (FFDM) was compared between patients with and without pCR using the Kaplan-Meier method. In patients without pCR, univariate and multivariable Cox analyses were used to determine factors predictive of distant metastasis. RESULTS: We identified 153 patients with median follow-up of 4.0 years (range, 0.5-14.0 years). After NAC, 108 had residual disease (pCR, 29%). Five-year FFDM was 98% and 55% in patients with and without pCR, respectively (P<.001). Factors independently predicting FFDM in patients without pCR were pathologic nodal positivity (hazard ratio, 3.08; 95% CI, 1.54-6.14; P=.001) and lymphovascular space invasion (hazard ratio, 1.91; 95% CI, 1.07-3.43; P=.030). Patients with a greater number of factors had worse FFDM; 5-year FFDM was 76.5% for patients with no factors (n=38) versus 54.9% and 27.5% for patients with 1 (n=44) and 2 factors (n=26), respectively (P<.001). CONCLUSIONS: Lack of pCR after NAC resulted in worse overall survival and FFDM, despite trimodality therapy. In patients with residual disease after NAC, pathologic lymph node positivity and lymphovascular space invasion predicted worse FFDM.


Asunto(s)
Terapia Neoadyuvante/métodos , Neoplasias de la Mama Triple Negativas/complicaciones , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Femenino , Humanos , Persona de Mediana Edad , Metástasis de la Neoplasia , Pronóstico , Neoplasias de la Mama Triple Negativas/patología
3.
J Biol Chem ; 293(31): 12095-12104, 2018 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-29903910

RESUMEN

Epithelial cells form tissues with many functions, including secretion and environmental separation and protection. Glandular epithelial tissues comprise cysts and tubules that are formed from a polarized, single-epithelial cell layer surrounding a central, fluid-filled lumen. The pathways regulating key processes in epithelial tissue morphogenesis such as mitotic spindle formation are incompletely understood, but are important to investigate, as their dysregulation is a signature of epithelial tumors. Here, we describe a signaling axis that manifests in a defect in mitotic spindle orientation during epithelial growth and cystogenesis. We found that activation of the small GTPase ADP-ribosylation factor 6 (ARF6) results in the sustained internalization of cell-surface components such as the cMet receptor and the cell-adhesion molecule E-cadherin. The spindle orientation defect arising from elevated levels of ARF6-GTP required an increase in cMet endocytosis, but was independent of E-cadherin internalization or elevated extracellular signal-regulated kinase (ERK) activity resulting from internalized receptor signaling on endosomes. Misorientation of the mitotic spindle resulted in the development of epithelial cysts with structural abnormalities, the most conspicuous of which was the presence of multiple intercellular lumens. Abnormal mitotic spindle orientation was necessary but insufficient to disrupt glandular development, as blocking the strong prosurvival signal resulting from ERK hyperactivation yielded structurally normal cysts despite continued manifestation of spindle orientation defects. Our findings highlight a previously unknown link between ARF6 activation, cMet receptor internalization, and mitotic spindle orientation during epithelial glandular morphogenesis.


Asunto(s)
Factores de Ribosilacion-ADP/metabolismo , Quistes/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Organoides/metabolismo , Huso Acromático/metabolismo , Factor 6 de Ribosilación del ADP , Factores de Ribosilacion-ADP/genética , Animales , Cadherinas/genética , Cadherinas/metabolismo , Adhesión Celular/efectos de los fármacos , División Celular , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Membrana Celular/ultraestructura , Polaridad Celular/efectos de los fármacos , Quistes/ultraestructura , Perros , Endocitosis , Endosomas/efectos de los fármacos , Endosomas/metabolismo , Endosomas/ultraestructura , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Flavonoides/farmacología , Regulación de la Expresión Génica , Células de Riñón Canino Madin Darby , Proteínas Asociadas a Microtúbulos/genética , Morfogénesis/genética , Organoides/efectos de los fármacos , Organoides/ultraestructura , Inhibidores de Proteínas Quinasas/farmacología , Transducción de Señal , Huso Acromático/efectos de los fármacos , Huso Acromático/ultraestructura , Técnicas de Cultivo de Tejidos
4.
Bioessays ; 37(12): 1309-16, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26439878

RESUMEN

Information transmission from tumor cells to non-tumor cells in the surrounding microenvironment via microvesicles is a more recently studied form of intercellular signaling that can have a marked impact on the tumor microenvironment. Tumor-derived microvesicles (TMVs) are packed with information including signaling proteins and nucleic acids, and can be taken up by target cells, enabling paracrine signaling. While previous research has focused on how vesicles released from pathologic cells differ from normal cells, the heterogeneity that exists within the TMV population itself is not fully characterized, and only beginning to be appreciated. In this review, we summarize current understanding of the biogenesis and roles of shed TMVs in the tumor microenvironment, and speculate on the consequences for tumor cell signaling in light of the hypothesis that there exists variance within the TMV population. The analysis of differential signaling upon cell-TMV interactions provides insights into potential mechanisms of intercellular communication.


Asunto(s)
Micropartículas Derivadas de Células/fisiología , Microambiente Tumoral/fisiología , Comunicación Celular/fisiología , Humanos , Transducción de Señal/fisiología
5.
Mol Cell Biol ; 39(3)2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30397076

RESUMEN

Tumor cell invasion is one result of the bidirectional interactions occurring between tumor cells and the surrounding milieu. The ability of tumor cells to invade through the extracellular matrix is in part regulated by the formation of a class of protease-loaded extracellular vesicles, called tumor microvesicles (TMVs), which are released directly from the cell surface. Here we show that the actin bundling protein, fascin, redistributes to the cell periphery in a ternary complex with podocalyxin and ezrin, where it promotes TMV release. The peripheral localization of fascin is prompted by the loss of Rab35 signaling, which in turn unleashes ARF6 activation. The result is a mechanism through which Rab35 and ARF6 cooperatively and simultaneously regulate the distribution and localization of fascin and promote oncogenic signaling, which leads to TMV release while inhibiting invadopodium formation. These studies are clinically significant as fascin-loaded TMVs can be detected in bodily fluids and elevated fascin expression coupled with low Rab35 levels correlates with poor overall survival in some cancers.


Asunto(s)
Factores de Ribosilacion-ADP/metabolismo , Proteínas Portadoras/metabolismo , Proteínas de Microfilamentos/metabolismo , Proteínas de Unión al GTP rab/metabolismo , Factor 6 de Ribosilación del ADP , Actinas/metabolismo , Proteínas Portadoras/fisiología , Línea Celular , Línea Celular Tumoral , Membrana Celular/metabolismo , Micropartículas Derivadas de Células/metabolismo , Citoplasma/metabolismo , Proteínas del Citoesqueleto/metabolismo , Matriz Extracelular/metabolismo , Humanos , Proteínas de Microfilamentos/fisiología , Invasividad Neoplásica/patología , Células PC-3 , Sialoglicoproteínas/metabolismo , Transducción de Señal , Microambiente Tumoral/fisiología
6.
Small GTPases ; 8(4): 220-232, 2017 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-27494381

RESUMEN

The ability of cells to transmit bioactive molecules to recipient cells and the extracellular environment is a fundamental requirement for both normal physiology and disease pathogenesis. It has traditionally been thought that soluble factors released from cells were responsible for this cellular signaling but recent research has revealed a fundamental role for microvesicles in this process. Microvesicles are heterogeneous membrane-bound sacs that are shed from the surface of cells into the extracellular environment in a highly regulated process. They are shed following the selective incorporation of a host of molecular cargo including multiple types of proteins and nucleic acids. In addition to providing new insight into the etiology of complex human diseases, microvesicles also show great promise as a tool for advanced diagnosis and therapy as we move forward into a new age of personalized medicine. Here we review current status of the rapidly evolving field of microvesicle biology, highlighting critical regulatory roles for several small GTPases in the biology and biogenesis of shed microvesicles.


Asunto(s)
Micropartículas Derivadas de Células/metabolismo , Transporte Biológico , Membrana Celular/metabolismo , Humanos , Metabolismo de los Lípidos , Enfermedades Neurodegenerativas/patología , Células Madre/citología
7.
JMIR Res Protoc ; 6(5): e87, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28506954

RESUMEN

BACKGROUND: Medication adherence remains a difficult problem to both assess and improve in patients. It is a multifactorial problem that goes beyond the commonly cited reason of forgetfulness. To date, eHealth (also known as mHealth and telehealth) interventions to improve medication adherence have largely been successful in improving adherence. However, interventions to date have used time- and cost-intensive strategies or focused solely on medication reminding, leaving much room for improvement in using a modality as flexible as eHealth. OBJECTIVE: Our objective was to develop and implement a fully automated short message service (SMS)-based medication adherence system, EpxMedTracking, that reminds patients to take their medications, explores reasons for missed doses, and alerts providers to help address problems of medication adherence in real time. METHODS: EpxMedTracking is a fully automated bidirectional SMS-based messaging system with provider involvement that was developed and implemented through Epharmix, Inc. Researchers analyzed 11 weeks of de-identified data from patients cared for by multiple provider groups in routine community practice for feasibility and functionality. Patients included were those in the care of a provider purchasing the EpxMedTracking tool from Epharmix and were enrolled from a clinic by their providers. The primary outcomes assessed were the rate of engagement with the system, reasons for missing doses, and self-reported medication adherence. RESULTS: Of the 25 patients studied over the 11 weeks, 3 never responded and subsequently opted out or were deleted by their provider. No other patients opted out or were deleted during the study period. Across the 11 weeks of the study period, the overall weekly engagement rate was 85.9%. There were 109 total reported missed doses including "I forgot" at 33 events (30.3%), "I felt better" at 29 events (26.6%), "out of meds" at 20 events (18.4%), "I felt sick" at 19 events (17.4%), and "other" at 3 events (2.8%). We also noted an increase in self-reported medication adherence in patients using the EpxMedTracking system. CONCLUSIONS: EpxMedTracking is an effective tool for tracking self-reported medication adherence over time. It uniquely identifies actionable reasons for missing doses for subsequent provider intervention in real time based on patient feedback. Patients enrolled on EpxMedTracking also self-report higher rates of medication adherence over time while on the system.

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