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1.
BMC Health Serv Res ; 19(1): 384, 2019 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-31196072

RESUMEN

BACKGROUND: When doctors have honest conversations with patients about their illness and involve them in decisions about their care, patients express greater satisfaction with care and lowered anxiety and depression. The Serious Illness Care Programme (the Programme), originally developed in the United States (U.S), promotes meaningful, realistic and focused conversations about patient's wishes, fears and worries for the future with their illness. The Serious Illness Conversation Guide (the guide) provides a framework to structure these conversations. The aim of this paper is to present findings from a study to examine the 'face validity', acceptability and relevance of the Guide for use within the United Kingdom (UK) health care setting. METHODS: A multi-stage approach was undertaken, using three separate techniques: 1. Nominal Group Technique with clinician 'expert groups' to review the Serious Illness Conversation Guide: 14 'experts' in Oncology, Palliative Care and Communication Skills; 2. Cognitive Interviews with 6 patient and public representatives, using the 'think aloud technique'; to explore the cognitive processes involved in answering the questions in the guide, including appropriateness of language, question wording and format 3. Final stakeholder review and consensus. RESULTS: Nominal Group Technique Unanimous agreement the conversation guide could provide a useful support to clinicians. Amendments are required but should be informed directly from the cognitive interviews. Training highlighted as key to underpin the use of the guide. Cognitive interviews The 'holistic' attention to the person as a whole was valued rather than a narrow focus on their disease. Some concern was raised regarding the 'formality' of some wording however and suggestions for amendments were made. Final stakeholder review Stakeholders agreed amendments to 5/13 prompts and unanimously agreed the UK guide should be implemented as a part of the pilot implementation of the Serious Illness Care Programme UK. CONCLUSION: Use of the guide has the potential to benefit patients, facilitating a 'person-centred' approach to these important conversations, and providing a framework to promote shared decision making and care planning. Further research is ongoing, to understand the impact of these conversations on patients, families and clinicians and on concordance of care delivery with expressed patient wishes.


Asunto(s)
Enfermedad Crítica/terapia , Planificación de Atención al Paciente , Actitud del Personal de Salud , Comunicación , Enfermedad Crítica/psicología , Toma de Decisiones , Investigación sobre Servicios de Salud , Humanos , Cuidados Paliativos , Planificación de Atención al Paciente/normas , Relaciones Profesional-Familia , Reino Unido
2.
Artículo en Inglés | MEDLINE | ID: mdl-27328871

RESUMEN

Transforming growth factors (TGFs) were discovered as activities that were secreted by cancer cells, and later by normal cells, and had the ability to phenotypically and reversibly transform immortalized fibroblasts. TGF-ß distinguished itself from TGF-α because it did not bind to the same epidermal growth factor (EGF) receptor as TGF-α and, therefore, acted through different cell-surface receptors and signaling mediators. This review summarizes the discovery of TGF-ß, the early developments in its molecular and biological characterization with its many biological activities in different cell and tissue contexts and its roles in disease, the realization that there is a family of secreted TGF-ß-related proteins with many differentiation functions in development and activities in normal cell and tissue physiology, and the subsequent identification and characterization of the receptors and effectors that mediate TGF-ß family signaling responses.


Asunto(s)
Factor de Crecimiento Transformador beta/fisiología , Animales , Clonación Molecular , ADN Complementario/genética , Humanos , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo
4.
Clin Teach ; 10(3): 151-4, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23656675

RESUMEN

BACKGROUND: Novel studies have previously highlighted the educational benefits of peer-led learning and peer marking of examinations. Limited data exist about the educational value of students writing their own exam questions and sharing these with other students. AIM: To evaluate the potential for medical students to learn about palliative care through the process of writing examination questions. methods: Fourth-year medical students on a palliative medicine rotation were invited to write a short-answer exam question in a similar format to the official examination run by the medical school. The questions were checked for accuracy and applicability by the coordinator, and were then distributed to students. The answers to the student-generated questions were discussed in a feedback forum at the end of the rotation. RESULTS: Twenty students took part in the exercise. All agreed the exercise was beneficial to their learning. Eighteen (90%) students did not feel the task was too much additional work. Eight (40%) students felt more confident in passing the official medical school exams. Students enjoyed the exercise, with 19 (95%) indicating that they were keen to repeat this in the future. CONCLUSION: Peer-led examination question writing could complement the delivery of palliative care teaching for medical students.


Asunto(s)
Educación de Pregrado en Medicina/métodos , Evaluación Educacional/métodos , Enseñanza/métodos , Escritura , Adulto , Curriculum , Inglaterra , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Cuidados Paliativos , Grupo Paritario , Encuestas y Cuestionarios
5.
PLoS One ; 5(3): e9832, 2010 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-20352126

RESUMEN

Carcinoma are complex societies of mutually interacting cells in which there is a progressive failure of normal homeostatic mechanisms, causing the parenchymal component to expand inappropriately and ultimately to disseminate to distant sites. When a cancer cell metastasizes, it first will be exposed to cancer associated fibroblasts in the immediate tumor microenvironment and then to normal fibroblasts as it traverses the underlying connective tissue towards the bloodstream. The interaction of tumor cells with stromal fibroblasts influences tumor biology by mechanisms that are not yet fully understood. Here, we report a role for normal stroma fibroblasts in the progression of invasive tumors to metastatic tumors. Using a coculture system of human metastatic breast cancer cells (MCF10CA1a) and normal murine dermal fibroblasts, we found that medium conditioned by cocultures of the two cell types (CoCM) increased migration and scattering of MCF10CA1a cells in vitro, whereas medium conditioned by homotypic cultures had little effect. Transient treatment of MCF10CA1a cells with CoCM in vitro accelerated tumor growth at orthotopic sites in vivo, and resulted in an expanded pattern of metastatic engraftment. The effects of CoCM on MCF10CA1a cells were dependent on small amounts of active TGF-beta1 secreted by fibroblasts under the influence of the tumor cells, and required intact ALK5-, p38-, and JNK signaling in the tumor cells. In conclusion, these results demonstrate that transient interactions between tumor cells and normal fibroblasts can modify the acellular component of the local microenvironment such that it induces long-lasting increases in tumorigenicity and alters the metastatic pattern of the cancer cells in vivo. TGF-beta appears to be a key player in this process, providing further rationale for the development of anti-cancer therapeutics that target the TGF-beta pathway.


Asunto(s)
Neoplasias de la Mama/patología , Fibroblastos/citología , Neoplasias/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Animales , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Movimiento Celular , Técnicas de Cocultivo , Medios de Cultivo Condicionados/farmacología , Femenino , Fibroblastos/metabolismo , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , Modelos Biológicos , Metástasis de la Neoplasia , Trasplante de Neoplasias
6.
Dev Biol ; 335(2): 305-16, 2009 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-19733164

RESUMEN

BMPs play multiple roles in development and BMP signaling is essential for lens formation. However, the mechanisms by which BMP receptors function in vertebrate development are incompletely understood. To determine the downstream effectors of BMP signaling and their functions in the ectoderm that will form the lens, we deleted the genes encoding the type I BMP receptors, Bmpr1a and Acvr1, and the canonical transducers of BMP signaling, Smad4, Smad1 and Smad5. Bmpr1a and Acvr1 regulated cell survival and proliferation, respectively. Absence of both receptors interfered with the expression of proteins involved in normal lens development and prevented lens formation, demonstrating that BMPs induce lens formation by acting directly on the prospective lens ectoderm. Remarkably, the canonical Smad signaling pathway was not needed for most of these processes. Lens formation, placode cell proliferation, the expression of FoxE3, a lens-specific transcription factor, and the lens protein, alphaA-crystallin were regulated by BMP receptors in a Smad-independent manner. Placode cell survival was promoted by R-Smad signaling, but in a manner that did not involve Smad4. Of the responses tested, only maintaining a high level of Sox2 protein, a transcription factor expressed early in placode formation, required the canonical Smad pathway. A key function of Smad-independent BMP receptor signaling may be reorganization of actin cytoskeleton to drive lens invagination.


Asunto(s)
Receptores de Activinas Tipo I/fisiología , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/fisiología , Cristalino/embriología , Transducción de Señal/fisiología , Receptores de Activinas Tipo I/genética , Animales , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/genética , Proliferación Celular , Supervivencia Celular , Cristalino/citología , Cristalino/metabolismo , Ratones , Ratones Transgénicos , Proteínas Smad/fisiología
7.
Development ; 136(10): 1741-50, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19369394

RESUMEN

There are conflicting reports about whether BMP signaling is required for eyelid closure during fetal development. This question was addressed using mice deficient in BMP or TGFbeta signaling in prospective eyelid and conjunctival epithelial cells. Genes encoding two type I BMP receptors, the type II TGFbeta receptor, two BMP- or two TGFbeta-activated R-Smads or the co-Smad Smad4 were deleted from the ocular surface ectoderm using Cre recombinase. Only mice with deletion of components of the BMP pathway had an 'eyelid open at birth' phenotype. Mice lacking Fgf10 or Fgfr2 also have open eyelids at birth. To better understand the pathways that regulate BMP expression and function during eyelid development, we localized BMPs and BMP signaling intermediates in Fgfr2 and Smad4 conditional knockout (CKO) mice. We found that Fgfr2 was required for the expression of Bmp4, the normal distribution of Shh signaling and for preserving the differentiation of the conjunctival epithelium. FGF signaling also promoted the expression of the Wnt antagonist Sfrp1 and suppressed Wnt signaling in the prospective eyelid epithelial cells, independently of BMP function. Transcripts encoding Foxc1 and Foxc2, which were previously shown to be necessary for eyelid closure, were not detectable in Smad4(CKO) animals. c-Jun, another key regulator of eyelid closure, was present and phosphorylated in eyelid periderm cells at the time of fusion, but failed to translocate to the nucleus in the absence of BMP function. Smad4(CKO) mice also showed premature differentiation of the conjunctival epithelium, conjunctival hyperplasia and the acquisition of epidermal characteristics, including formation of an ectopic row of hair follicles in place of the Meibomian glands. A second row of eyelashes is a feature of human lymphedema-distichiasis syndrome, which is associated with mutations in FOXC2.


Asunto(s)
Proteínas Morfogenéticas Óseas/fisiología , Conjuntiva/embriología , Conjuntiva/crecimiento & desarrollo , Células Epiteliales/citología , Párpados/embriología , Párpados/crecimiento & desarrollo , Factores de Crecimiento de Fibroblastos/fisiología , Animales , Animales Recién Nacidos , Proteína Morfogenética Ósea 4/biosíntesis , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/genética , Diferenciación Celular/fisiología , Conjuntiva/anomalías , Conjuntiva/citología , Células Epiteliales/metabolismo , Párpados/anomalías , Factores de Transcripción Forkhead/metabolismo , Folículo Piloso/embriología , Folículo Piloso/crecimiento & desarrollo , Proteínas Hedgehog/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Ratones , Ratones Noqueados , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/genética , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/metabolismo , Transducción de Señal , Proteínas Smad Reguladas por Receptores/genética , Proteína Smad4/genética , Proteína Smad4/metabolismo
8.
J Biol Chem ; 284(18): 12246-57, 2009 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-19265200

RESUMEN

Pancreatic islet beta-cell dysfunction is a signature feature of Type 2 diabetes pathogenesis. Consequently, knowledge of signals that regulate beta-cell function is of immense clinical relevance. Transforming growth factor (TGF)-beta signaling plays a critical role in pancreatic development although the role of this pathway in the adult pancreas is obscure. Here, we define an important role of the TGF-beta pathway in regulation of insulin gene transcription and beta-cell function. We identify insulin as a TGF-beta target gene and show that the TGF-beta signaling effector Smad3 occupies the insulin gene promoter and represses insulin gene transcription. In contrast, Smad3 small interfering RNAs relieve insulin transcriptional repression and enhance insulin levels. Transduction of adenoviral Smad3 into primary human and non-human primate islets suppresses insulin content, whereas, dominant-negative Smad3 enhances insulin levels. Consistent with this, Smad3-deficient mice exhibit moderate hyperinsulinemia and mild hypoglycemia. Moreover, Smad3 deficiency results in improved glucose tolerance and enhanced glucose-stimulated insulin secretion in vivo. In ex vivo perifusion assays, Smad3-deficient islets exhibit improved glucose-stimulated insulin release. Interestingly, Smad3-deficient islets harbor an activated insulin-receptor signaling pathway and TGF-beta signaling regulates expression of genes involved in beta-cell function. Together, these studies emphasize TGF-beta/Smad3 signaling as an important regulator of insulin gene transcription and beta-cell function and suggest that components of the TGF-beta signaling pathway may be dysregulated in diabetes.


Asunto(s)
Células Secretoras de Insulina/metabolismo , Insulina/biosíntesis , Transducción de Señal , Proteína smad3/metabolismo , Transcripción Genética , Factor de Crecimiento Transformador beta/metabolismo , Animales , Línea Celular , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Glucosa/genética , Glucosa/metabolismo , Humanos , Hiperinsulinismo/genética , Hiperinsulinismo/metabolismo , Hipoglucemia/genética , Hipoglucemia/metabolismo , Insulina/genética , Ratones , Ratones Noqueados , Primates , Regiones Promotoras Genéticas , ARN Interferente Pequeño/genética , Proteína smad3/antagonistas & inhibidores , Proteína smad3/genética , Factor de Crecimiento Transformador beta/genética
9.
Cancer Res ; 68(18): 7278-82, 2008 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-18794114

RESUMEN

We investigated the influence of acute wounding on tumor growth in a syngeneic mouse breast cancer model. Metastatic mouse breast cancer cells (4T1) were orthotopically injected into the mammary fat pads of BALB/c mice, and animals were wounded locally by full thickness dermal incisions above the mammary fat pads or remotely above the scapula 9 days later. Local, but not remote, wounding increased tumor size when compared with sham treatment. Injection of wound fluid close to the tumor site increased tumor growth, whereas in vitro wound fluid compared with serum increased the proliferation rate of 4T1 cells. Our results show that wound stroma can unfavorably influence growth of nearby tumors. This effect is T cell-dependent, as local wounding had no effect on tumor growth in nu/nu mice. The effect of wounding on tumor growth can be mimicked by acellular wound fluid, suggesting that T cells secrete or mediate secretion of cytokines or growth factors that then accelerate tumor growth. Here, we define an experimental model of wound-promoted tumor growth that will enable us to identify mechanisms and therapeutic targets to reduce the negative effect of tissue repair on residual tumors.


Asunto(s)
Transformación Celular Neoplásica/patología , Glándulas Mamarias Animales/lesiones , Neoplasias Mamarias Experimentales/patología , Linfocitos T/patología , Heridas y Lesiones/patología , Animales , Procesos de Crecimiento Celular/fisiología , Modelos Animales de Enfermedad , Femenino , Glándulas Mamarias Animales/patología , Neoplasias Mamarias Experimentales/inmunología , Ratones , Ratones Endogámicos BALB C , Linfocitos T/inmunología , Heridas y Lesiones/inmunología
10.
Invest Ophthalmol Vis Sci ; 49(11): 4953-60, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18566469

RESUMEN

PURPOSE: Bone morphogenetic protein (BMP) signaling is essential for the induction and subsequent development of the lens. The purpose of this study was to analyze the function(s) of the type 1 BMP receptor, Acvr1, in lens development. METHODS: Acvr1 was deleted from the surface ectoderm of mouse embryos on embryonic day 9 using the Cre-loxP METHOD: Cell proliferation, cell cycle exit, and apoptosis were measured in tissue sections by immunohistochemistry, immunofluorescence, and TUNEL staining. RESULTS: Lenses formed in the absence of Acvr1. However, Acvr1(CKO) (conditional knockout) lenses were small. Acvr1 signaling promoted proliferation at early stages of lens formation but inhibited proliferation at later stages. Inhibition of cell proliferation by Acvr1 was necessary for the proper regionalization of the lens epithelium and promoted the withdrawal of lens fiber cells from the cell cycle. In spite of the failure of all Acvr1(CKO) fiber cells to withdraw from the cell cycle, they expressed proteins characteristic of differentiated fiber cells. Although the stimulation of proliferation was Smad independent, the ability of Acvr1 to promote cell cycle exit later in development depended on classical R-Smad-Smad4 signaling. Loss of Acvr1 led to an increase in apoptosis of lens epithelial and fiber cells. Increased cell death, together with the initial decrease in proliferation, appeared to account for the smaller sizes of the Acvr1(CKO) lenses. CONCLUSIONS: This study revealed a novel switch in the functions of Acvr1 in regulating lens cell proliferation. Previously unknown functions mediated by this receptor included regionalization of the lens epithelium and cell cycle exit during fiber cell differentiation.


Asunto(s)
Receptores de Activinas Tipo I/metabolismo , Envejecimiento/metabolismo , Proliferación Celular , Cristalino/crecimiento & desarrollo , Receptores de Activinas Tipo II , Animales , Animales Recién Nacidos , Ciclo Celular/fisiología , Supervivencia Celular , Femenino , Cristalino/citología , Cristalino/metabolismo , Ratones , Ratones Transgénicos , Embarazo , Transducción de Señal
11.
Am J Pathol ; 173(1): 68-76, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18502822

RESUMEN

Our previous work showed that 6 weeks after cutaneous irradiation, mice null (knockout, KO) for Smad3, a cytoplasmic downstream mediator of transforming growth factor-beta, demonstrate less epidermal acanthosis and dermal inflammation than wild-type (WT) Smad3 mice. Analysis of the kinetics of inflammation showed that 6 to 8 hours after skin irradiation, there was a transient sevenfold increase in neutrophil influx in Smad3 KO mice compared with WT. Herein we describe bone marrow transplantation and skin grafting between WT and KO mice to assess the contribution of the neutrophil genotype compared with that of irradiated skin to the induction of neutrophil migration after irradiation. Results from bone marrow transplantation showed that WT marrow transplanted into KO mice enhanced neutrophil migration 6 to 8 hours after irradiation by 3.2-fold compared with KO marrow in WT mice. KO skin grafted onto either WT or KO animals showed a sixfold elevation of neutrophils after irradiation compared with grafted WT skin. These results suggest that the genotype of the irradiated skin, rather than the inflammatory cell, controls neutrophil influx. Circulating neutrophils, increased in WT mice after injection of granulocyte colony-stimulating factor, resulted in increased neutrophil migration to the skin 6 to 8 hours after irradiation and less skin damage 6 weeks after irradiation compared with untreated WT mice. Thus, early responses, including enhanced neutrophil influx, appear to contribute to subsequent cutaneous radioprotection.


Asunto(s)
Infiltración Neutrófila/efectos de la radiación , Piel/efectos de la radiación , Proteína smad3/deficiencia , Proteína smad3/genética , Animales , Trasplante de Médula Ósea , Quimiocina CXCL1/biosíntesis , Quimiocina CXCL2/biosíntesis , Genotipo , Ratones , Ratones Noqueados , Infiltración Neutrófila/inmunología , Piel/inmunología , Trasplante de Piel
13.
Biotechniques ; 43(3): 289-90, 292, 294, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17907571

RESUMEN

Canonical TGF-beta is involved in cell differentiation, tissue maintenance, and wound healing, but also plays a central role in the pathogenesis of diseases such as cancer Here we describe a lentivirus-based reporter vector system expressing green fluorescent protein (GFP) or red fluorescent protein (RFP) under the control of a Smad3-responsive element (CAGA)12 that allows observation of the temporospatial pattern of endogeneous Smad3-mediated signaling on a cellular level. Use of this method will be valuable to identify cells with active Smad3 signaling and investigate the role of endogenous Smad3 signaling in complex systems such as co-cultures in vitro, or in tumors during tumor cell invasion and metastasis in vivo.


Asunto(s)
Neoplasias de la Mama/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Lentivirus/genética , Microscopía Fluorescente/métodos , Transducción de Señal , Proteína smad3/metabolismo , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Genes Reporteros/genética , Proteínas Fluorescentes Verdes/genética , Humanos , Ratones , Regiones Promotoras Genéticas/genética , Proteína smad3/genética , Transfección/métodos
14.
J Dermatol Sci ; 48(1): 35-42, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17624738

RESUMEN

BACKGROUND: Transforming growth factor-beta1 (TGF-beta1), a key biological mediator following ionizing radiation, plays a role in a complex tissue reaction involved in local radiation-induced pathological damage. Knocking out Smad3 (S3KO), a downstream signaling intermediate in the TGF-beta pathway, in mice protects their skin from radiation damage as demonstrated by decreased epithelial acanthosis and dermal fibrosis as compared to Smad3 wild-type (S3WT) mice. OBJECTIVE: The present study was designed to investigate the molecular mechanisms contributing to increased radioprotection in the absence of Smad3. METHODS: Primary dermal fibroblasts derived from S3WT and KO mice were exposed to 5Gy ionizing radiation in vitro. Western blot analyses, immunocytochemistry, and reporter transfections were used to dissect the radiation-induced events. RESULTS: There was increased phosphorylation of ERK-MAPK, p53 and H2A.X in S3KO compared to the S3WT fibroblasts, implicating them in a key signaling cascade in response of these cells to radiation. Pro-fibrotic gene expression was decreased in S3KO fibroblasts post-irradiation. CONCLUSION: The absence of Smad3 may decrease radio-responsiveness by increasing activation of DNA damage sensing mechanisms and decreasing induction of pro-fibrotic genes.


Asunto(s)
Dermis/citología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Fibroblastos/metabolismo , Fibroblastos/efectos de la radiación , Radiación Ionizante , Proteína smad3/metabolismo , Animales , Proliferación Celular/efectos de la radiación , Células Cultivadas , Daño del ADN/efectos de la radiación , Histonas/metabolismo , Ratones , Ratones Noqueados , Traumatismos por Radiación/prevención & control , Proteína smad3/genética , Transfección , Proteína p53 Supresora de Tumor/metabolismo
15.
Nat Med ; 13(8): 952-61, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17660828

RESUMEN

Cardiac fibrosis, associated with a decreased extent of microvasculature and with disruption of normal myocardial structures, results from excessive deposition of extracellular matrix, which is mediated by the recruitment of fibroblasts. The source of these fibroblasts is unclear and specific anti-fibrotic therapies are not currently available. Here we show that cardiac fibrosis is associated with the emergence of fibroblasts originating from endothelial cells, suggesting an endothelial-mesenchymal transition (EndMT) similar to events that occur during formation of the atrioventricular cushion in the embryonic heart. Transforming growth factor-beta1 (TGF-beta1) induced endothelial cells to undergo EndMT, whereas bone morphogenic protein 7 (BMP-7) preserved the endothelial phenotype. The systemic administration of recombinant human BMP-7 (rhBMP-7) significantly inhibited EndMT and the progression of cardiac fibrosis in mouse models of pressure overload and chronic allograft rejection. Our findings show that EndMT contributes to the progression of cardiac fibrosis and that rhBMP-7 can be used to inhibit EndMT and to intervene in the progression of chronic heart disease associated with fibrosis.


Asunto(s)
Diferenciación Celular , Fibrosis Endomiocárdica/patología , Células Endoteliales/patología , Mesodermo/patología , Animales , Células de la Médula Ósea/patología , Proteína Morfogenética Ósea 7 , Proteínas Morfogenéticas Óseas/farmacología , Proteínas Morfogenéticas Óseas/uso terapéutico , Línea Celular , Células Cultivadas , Enfermedad Crónica , Fibrosis Endomiocárdica/tratamiento farmacológico , Células Endoteliales/efectos de los fármacos , Humanos , Células Madre Mesenquimatosas/patología , Mesodermo/efectos de los fármacos , Ratones , Ratones Transgénicos , Factor de Crecimiento Transformador beta/farmacología , Factor de Crecimiento Transformador beta/uso terapéutico , Factor de Crecimiento Transformador beta1/farmacología
16.
Mol Cell ; 24(5): 771-783, 2006 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-17157259

RESUMEN

Using a yeast two-hybrid screen, we found that SNIP1 (Smad nuclear-interacting protein 1) associates with c-Myc, a key regulator of cell proliferation and transformation. We demonstrate that SNIP1 functions as an important regulator of c-Myc activity, binding the N terminus of c-Myc through its own C terminus, and that SNIP1 enhances the transcriptional activity of c-Myc both by stabilizing it against proteosomal degradation and by bridging the c-Myc/p300 complex. These effects of SNIP1 on c-Myc likely contribute to synergistic effects of SNIP1, c-Myc, and H-Ras in inducing formation of foci in an in vitro transformation assay and also in supporting anchorage-independent growth. The significant association of SNIP1 and c-Myc staining in a non-small cell lung cancer tissue array is further evidence that their activities might be linked and suggests that SNIP1 might be an important modulator of c-Myc activity in carcinogenesis.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Regiones Promotoras Genéticas/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Transcripción Genética , Línea Celular , Células Cultivadas , Inmunoprecipitación de Cromatina , Humanos , Inmunohistoquímica , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas Proto-Oncogénicas c-myc/genética , ARN Interferente Pequeño/metabolismo , Proteínas de Unión al ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Quinasas Asociadas a Fase-S/metabolismo , Sensibilidad y Especificidad , Análisis de Matrices Tisulares , Técnicas del Sistema de Dos Híbridos
17.
Proc Natl Acad Sci U S A ; 103(24): 9250-5, 2006 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-16754864

RESUMEN

The loss of TGFbeta or its downstream mediator, Smad3, key players in tissue repair, accelerates closure of incisional wounds in mice. In contrast, we now report that excisional ear wounds in mice lacking Smad3 enlarge compared with wild-type controls resulting from changes in extracellular matrix molecules, which alter the mechanotransduction properties of these wounds. Specifically, levels of elastin and glycosoaminoglycans are increased, collagen fibers are more compactly organized, and matrix modulators like integrins, TGFbeta1, and matrix metalloproteinases (MMPs) are altered both basally and after wounding in Smad3 knockout mice. Mechanical testing of dorsal skin correlates these changes in matrix composition with functional parameters, specifically an increased elastic modulus, suggesting an imbalance of tissue forces. We propose that the altered mechanical elastic properties translate into a persistent retractile force that is opposed by decreased wound contractile forces contributing to the enlarging ear wound in Smad3 knockout mice. These studies highlight a previously undescribed role for Smad3 in the mechanotransduction of matrix unsupported ear wound closure.


Asunto(s)
Matriz Extracelular , Mecanotransducción Celular/fisiología , Piel/metabolismo , Proteína smad3/metabolismo , Cicatrización de Heridas , Animales , Biomarcadores/metabolismo , Trasplante de Médula Ósea , Células Cultivadas , Oído Externo/metabolismo , Oído Externo/patología , Elasticidad , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Fibroblastos/citología , Fibroblastos/metabolismo , Integrina alfaVbeta3/metabolismo , Integrinas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Tirosina Quinasas/metabolismo , Receptores de Vitronectina/metabolismo , Piel/patología , Proteína smad3/genética , Estrés Mecánico
18.
Am J Obstet Gynecol ; 195(5): 1388-95, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16777050

RESUMEN

OBJECTIVES: We investigated the impact of selective laser ablation on the cardiovascular pathology of the recipient twin in twin-twin transfusion syndrome. STUDY DESIGN: Fetal echocardiograms and medical records were reviewed from 22 pregnancies with severe twin-twin transfusion syndrome where echocardiography was performed before and after laser. RESULTS: Before laser, cardiomegaly associated with right and/or left ventricular hypertrophy without ventricular dilatation, was observed in most cases. Right ventricular and left ventricular systolic dysfunction (shortening fraction <28%) was present in 59% and 27%, respectively, and diastolic dysfunction (based on inflow and venous Dopplers) in 73%. Shortly after laser, biventricular systolic function improved significantly and diastolic function tended to improve (50%, P = .06). Functional pulmonary atresia, secondary to right ventricular systolic dysfunction, resolved in 2 of 2 cases at post-laser echocardiography. On serial assessment, diastolic function was normal in 7 of 10, hydrops regressed in 4 of 5, and neither progressive myocardial hypertrophy nor anatomical right ventricular outflow obstruction were found. CONCLUSIONS: Selective laser ablation in severe twin-twin transfusion syndrome acutely improves biventricular systolic function and tends to improve diastolic function in the recipient twin.


Asunto(s)
Anastomosis Arteriovenosa/cirugía , Cardiomegalia/embriología , Transfusión Feto-Fetal/cirugía , Cardiopatías/embriología , Terapia por Láser , Placenta/irrigación sanguínea , Gemelos , Adulto , Cardiomegalia/diagnóstico por imagen , Ecocardiografía , Femenino , Transfusión Feto-Fetal/diagnóstico por imagen , Transfusión Feto-Fetal/fisiopatología , Cardiopatías/fisiopatología , Humanos , Hidropesía Fetal/fisiopatología , Embarazo , Índice de Severidad de la Enfermedad , Función Ventricular
19.
BMC Cancer ; 6: 25, 2006 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-16438724

RESUMEN

BACKGROUND: Although transforming growth factor beta (TGF-beta) typically inhibits proliferation of epithelial cells, consistent with a tumor suppressor activity, it paradoxically also exhibits pro-metastatic activity in the later stages of carcinogenesis. Since tumors often display altered TGF-beta signaling, particularly involving the Smad-pathway, we investigated the role of Smad4-expression in breast cancer. METHODS: Smad4 expression was investigated by immunohistochemistry in formalin-fixed, paraffin-embedded tissue from 197 samples of primary breast cancer obtained between 1986 and 1998. The prognostic value of Smad4-expression was analyzed. RESULTS: Smad4 expression was found to be reduced in lobular and ductal breast carcinoma as compared to surrounding uninvolved lobular and ductal breast epithelia (p < 0.001, n = 50). Smad4-expression correlated positively with expression of TGF-beta-receptor I (p < 0.001, n = 197) and TGF-beta-receptor II (p < 0.001, n = 197), but showed no significant correlation with tumor size, metastases, nodal status, histological grade, histological type, or estrogen receptor expression. While not achieving statistical significance, there was a trend towards longer survival times in patients with Smad4 negative tumors. CONCLUSION: According to the suggested role of Smad4 as a tumor suppressor we observed that expression of Smad4 is lower in human breast cancer than in surrounding breast epithelium. However, we also observed a trend towards longer survival times in Smad4-negative patients, indicating the complex role of TGF-beta signaling in tumor progression.


Asunto(s)
Neoplasias de la Mama/química , Proteína Smad4/análisis , Adulto , Anciano , Anciano de 80 o más Años , Mama/química , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Pronóstico , Receptores de Estrógenos/análisis , Receptores de Factores de Crecimiento Transformadores beta/análisis , Estudios Retrospectivos , Tasa de Supervivencia
20.
Cytokine Growth Factor Rev ; 17(1-2): 19-27, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16290023

RESUMEN

Smads2 and 3 transduce signals of TGF-beta from the cell surface to the nucleus. We used mice with a targeted deletion of Smad3 to study the specific contributions of this signaling pathway to pathogenic effects of TGF-beta. Focusing on models involving epithelial-to-mesenchymal transition (EMT), including injury to the lens and retina of the eye and to the kidney, we have found that loss of Smad3 blocks EMT and attenuates development of fibrotic sequelae. Smad3 also plays a critical role in both the tumor suppressor and pro-metastatic effects of TGF-beta in carcinogenesis. These observations suggest that development of small molecule inhibitors of Smad3 might have clinical application in treatment of fibrotic diseases as well as late stage cancers.


Asunto(s)
Células Epiteliales/metabolismo , Mesodermo/citología , Metástasis de la Neoplasia/patología , Neoplasias/prevención & control , Proteína smad3/fisiología , Factor de Crecimiento Transformador beta/fisiología , Animales , Diferenciación Celular/fisiología , Membrana Celular/inmunología , Membrana Celular/metabolismo , Núcleo Celular/inmunología , Núcleo Celular/metabolismo , Fibrosis/metabolismo , Humanos , Mesodermo/metabolismo , Neoplasias/metabolismo , Transducción de Señal/fisiología , Factor de Crecimiento Transformador beta/genética
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