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1.
Arch Orthop Trauma Surg ; 142(8): 1769-1773, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33586032

RESUMEN

INTRODUCTION: The majority of neck of femur (NOF) fracture patients are frail and at a higher risk of cardiac arrest. This makes discussion of treatment escalation vital to informed care. The optimal time for these discussions is prior to admission or trauma. However, when this has not occurred, it is vital that these discussions happen early in the patient's admission when family is often present and before further deterioration in their condition. We undertook a service evaluation to evaluate and discuss the effect of clinician education on improving rates of timely discussion amongst orthopaedic doctors. MATERIALS AND METHODS: The first cycle included 94 patients. Their notes were reviewed for presence of a ReSPECT (Recommend Summary Plan for Emergency Care and Treatment) form prior to operation and whether this it countersigned by a consultant. Following this, clinician education was undertaken and a re-audit was carried out involving 57 patients. RESULTS: ReSPECT form completion rates rose from 23% in cycle 1-32% in cycle 2 following intervention. The proportion which consultants signed rose from 41% to 56% following intervention. CONCLUSION: This project demonstrates how a basic education program can prove limited improvements in the rates of timely resuscitation discussions. We discuss a current lack in quality research into educational programs for discussion of treatment escalation for orthopaedic trainees. We suggest there is room to improve national best practice guidelines and training to ensure these discussions are carried out more frequently and to a better standard.


Asunto(s)
Fracturas del Cuello Femoral , Ortopedia , Fracturas del Cuello Femoral/cirugía , Hospitalización , Humanos
2.
J Small Anim Pract ; 61(6): 374-380, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32323333

RESUMEN

OBJECTIVES: To investigate the effect of breed as a risk factor associated with humeral condylar fracture in skeletally immature dogs in the UK. MATERIALS AND METHODS: Retrospective study of dogs under 12 months of age that were presented with humeral condylar fracture to three specialist referral centres between 2015 and 2018. Data retrieved from medical records included breed, age, gender, neuter status, affected limb, fracture configuration and aetiology of the fracture. Breed population percentages were compared with those recorded by the UK Kennel Club. RESULTS: Of the 115 dogs with 118 fractures, French bulldogs (41%) and English springer spaniels (15%) were overrepresented: humeral condylar fractures were more commonly diagnosed in French bulldogs (odds ratio = 5.86) and English springer spaniels (odds ratio = 5.66) compared with mixed-breed dogs. Lateral condylar fractures occurred in 70% of cases, with medial condylar fractures and Y/T fractures accounting for 9% and 21%, respectively. Median age at the time of fracture was 4 months (range 2 to 10 months). CLINICAL SIGNIFICANCE: French bulldogs and English springer spaniels were identified as being at potentially increased risk of humeral condylar fracture in skeletally immature dogs.


Asunto(s)
Enfermedades de los Perros , Fracturas del Húmero/veterinaria , Animales , Cruzamiento , Perros , Húmero , Estudios Retrospectivos , Factores de Riesgo
3.
Br J Anaesth ; 122(2): 180-187, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30686303

RESUMEN

BACKGROUND: Systemic inflammation is pivotal in the pathogenesis of cardiovascular disease. As inflammation can directly cause cardiomyocyte injury, we hypothesised that established systemic inflammation, as reflected by elevated preoperative neutrophil-lymphocyte ratio (NLR) >4, predisposes patients to perioperative myocardial injury. METHODS: We prospectively recruited 1652 patients aged ≥45 yr who underwent non-cardiac surgery in two UK centres. Serum high sensitivity troponin T (hsTnT) concentrations were measured on the first three postoperative days. Clinicians and investigators were blinded to the troponin results. The primary outcome was perioperative myocardial injury, defined as hsTnT≥14 ng L-1 within 3 days after surgery. We assessed whether myocardial injury was associated with preoperative NLR>4, activated reactive oxygen species (ROS) generation in circulating monocytes, or both. Multivariable logistic regression analysis explored associations between age, sex, NLR, Revised Cardiac Risk Index, individual leukocyte subsets, and myocardial injury. Flow cytometric quantification of ROS was done in 21 patients. Data are presented as n (%) or odds ratio (OR) with 95% confidence intervals. RESULTS: Preoperative NLR>4 was present in 239/1652 (14.5%) patients. Myocardial injury occurred in 405/1652 (24.5%) patients and was more common in patients with preoperative NLR>4 [OR: 2.56 (1.92-3.41); P<0.0001]. Myocardial injury was independently associated with lower absolute preoperative lymphocyte count [OR 1.80 (1.50-2.17); P<0.0001] and higher absolute preoperative monocyte count [OR 1.93 (1.12-3.30); P=0.017]. Monocyte ROS generation correlated with NLR (r=0.47; P=0.03). CONCLUSIONS: Preoperative NLR>4 is associated with perioperative myocardial injury, independent of conventional risk factors. Systemic inflammation may contribute to the development of perioperative myocardial injury. CLINICAL TRIAL REGISTRATION: NCT01842568.


Asunto(s)
Lesiones Cardíacas/etiología , Procedimientos Quirúrgicos Operativos/métodos , Síndrome de Respuesta Inflamatoria Sistémica/complicaciones , Anciano , Estudios de Cohortes , Femenino , Humanos , Complicaciones Intraoperatorias/etiología , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Monocitos/metabolismo , Complicaciones Posoperatorias/epidemiología , Estudios Prospectivos , Especies Reactivas de Oxígeno/metabolismo , Factores de Riesgo , Resultado del Tratamiento , Troponina T/sangre
5.
J Small Anim Pract ; 52(11): 608-11, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22026743

RESUMEN

An 8·5-year-old, female, neutered, Rottweiler was presented for investigation of progressive ataxia of one week duration. Proprioception was absent in the left pelvic limb and reduced on the right, thoracolumbar hyperalgesia was evident and pelvic limb segmental spinal reflexes were normal. Magnetic resonance imaging (MRI) demonstrated a spherical region of signal void compressing the spinal cord between the fifth and sixth thoracic vertebrae and several non-compressive degenerate intervertebral discs. Computed tomography (CT) of the region confirmed the findings and identified the lesion as gas. A dorsolateral hemilaminectomy was performed to decompress the spinal cord and achieved complete resolution of the clinical signs on examination after 3 months. This is the first known reported case of spontaneous pneumorrhachis in a veterinary patient.


Asunto(s)
Perros/lesiones , Perros/cirugía , Laminectomía/veterinaria , Traumatismos de la Médula Espinal/veterinaria , Traumatismos Torácicos/veterinaria , Animales , Femenino , Imagen por Resonancia Magnética/veterinaria , Traumatismos de la Médula Espinal/diagnóstico , Traumatismos de la Médula Espinal/cirugía , Traumatismos Torácicos/diagnóstico , Traumatismos Torácicos/cirugía , Vértebras Torácicas/lesiones , Vértebras Torácicas/cirugía , Tomografía Computarizada por Rayos X/veterinaria , Resultado del Tratamiento
6.
J Biol Chem ; 276(27): 25190-6, 2001 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-11335715

RESUMEN

The mechanism of action of Endostatin, an endogenous inhibitor of angiogenesis and tumor growth, remains unknown. We utilized phage-display technology to identify polypeptides that mimic the binding domains of proteins with which Endostatin interacts. A conformed peptide (E37) was identified that shares an epitope with human tropomyosin implicating tropomyosin as an Endostatin-binding protein. We show that recombinant human Endostatin binds tropomyosin in vitro and to tropomyosin-associated microfilaments in a variety of endothelial cell types. The most compelling evidence that tropomyosin modulates the activity of Endostatin was demonstrated when E37 blocked greater than 84% of the tumor-growth inhibitory activity of Endostatin in the B16-BL6 metastatic melanoma model. We conclude that the E37 peptide mimics the Endostatin-binding epitope of tropomyosin and blocks the antitumor activity of Endostatin by competing for Endostatin binding. We postulate that the Endostatin interaction with tropomyosin results in disruption of microfilament integrity leading to inhibition of cell motility, induction of apoptosis, and ultimately inhibition of tumor growth.


Asunto(s)
Antineoplásicos/metabolismo , Colágeno/metabolismo , Fragmentos de Péptidos/metabolismo , Tropomiosina/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Animales , Apoptosis , Bacteriófagos , Sitios de Unión , Línea Celular , Pollos , Electroforesis en Gel de Poliacrilamida , Endostatinas , Ensayo de Inmunoadsorción Enzimática , Mapeo Epitopo , Técnica del Anticuerpo Fluorescente , Humanos , Cinética , Imitación Molecular , Conejos , Proteínas Recombinantes/metabolismo
7.
Neuroreport ; 11(16): 3453-6, 2000 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-11095498

RESUMEN

Inducible nitric oxide synthase (iNOS) has been reported in tangle-bearing neurons of patients with Alzheimer's disease (AD), and can be induced by tumor necrosis factor-alpha (TNFalpha). High CNS levels of TNFalpha are associated with neurodegenerative diseases such as AD, where neurons dependent on neurotrophins such as nerve growth factor (NGF) are particularly affected. In this study we determined the effect of TNFalpha on iNOS in NGF-responsive pheochromocytoma (PC12) cells. We found that while TNFalpha and NGF alone were unable to induce iNOS, their simultaneous addition resulted in iNOS induction and the release of nitric oxide. Our results suggest that synergistic iNOS induction by TNFalpha and NGF may occur in selective population of NGF-responsive neurons in the presence of elevated CNS levels of TNFalpha.


Asunto(s)
Factor de Crecimiento Nervioso/farmacología , Óxido Nítrico Sintasa/biosíntesis , Factor de Necrosis Tumoral alfa/farmacología , Neoplasias de las Glándulas Suprarrenales/enzimología , Animales , Carbazoles/farmacología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Inducción Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Alcaloides Indólicos , Óxido Nítrico Sintasa de Tipo II , Células PC12 , Feocromocitoma/enzimología , Ratas
8.
Cancer Metastasis Rev ; 19(1-2): 181-90, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11191058

RESUMEN

Considerable progress has been made in the understanding of the molecular structure and mechanistic aspects of Angiostatin and Endostatin, endogenous angiogenesis inhibitors that have been shown to regress tumors in murine models. The growing body of literature surrounding these molecules and on the efficacy of these proteins is in part due to the ability to generate these proteins in recombinant systems as well characterized molecules. Recombinant human Angiostatin and Endostatin are in Phase I trials, following the manufacture of clinical grade material at large scale. This review highlights the recent advances made on understanding the structure and function of Angiostatin and Endostatin.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Antineoplásicos/uso terapéutico , Colágeno/fisiología , Colágeno/uso terapéutico , Neoplasias/tratamiento farmacológico , Fragmentos de Péptidos/fisiología , Fragmentos de Péptidos/uso terapéutico , Plasminógeno/fisiología , Plasminógeno/uso terapéutico , Inhibidores de la Angiogénesis/toxicidad , Angiostatinas , Animales , Antineoplásicos/toxicidad , Ensayos Clínicos como Asunto , Colágeno/toxicidad , Endostatinas , Humanos , Neoplasias/irrigación sanguínea , Neoplasias/patología , Neoplasias Experimentales/irrigación sanguínea , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Fragmentos de Péptidos/toxicidad , Plasminógeno/toxicidad , Proteínas Recombinantes/uso terapéutico
9.
J Anat ; 197 Pt 4: 543-51, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11197527

RESUMEN

Age-associated neurodegenerative diseases such as Alzheimer's disease are characterised by neuronal impairment that leads to cognitive deficits. As certain affected neurons depend on trophic factors such as neurotrophins (NTs), impairment in NT function has been suggested to be a component of neuronal damage associated with such disorders. Age-related neurodegenerative diseases are also characterised by high levels of proinflammatory cytokines such as tumour necrosis factor alpha (TNFalpha) in the CNS. Because TNFalpha receptors and certain NT receptors share a high degree of homology and are capable of activating similar signalling pathways, one possibility is that altered cytokine levels may affect NT function in the aged or diseased CNS. Here we wish briefly to review the evidence suggesting a role for cytokine and NT in the onset of age-associated neurodegenerative diseases. We propose that cytokine/NT interactions may alter neuronal homeostasis, thus possibly contributing to some of the neuronal degeneration occurring during such age-associated CNS diseases.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Sistema Nervioso Central/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo , Anciano , Anciano de 80 o más Años , Envejecimiento , Homeostasis , Humanos , Neuronas/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Receptores del Factor de Necrosis Tumoral/metabolismo
10.
Biochem Biophys Res Commun ; 264(2): 469-77, 1999 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-10529387

RESUMEN

Angiostatin protein, which comprises the first four kringle domains of plasminogen, is an endogenous inhibitor of angiogenesis that inhibits the growth of experimental primary and metastatic tumors. Truncation of Angiostatin K1-4 to K1-3 retained the activity of Angiostatin. We recombinantly expressed full-length human Angiostatin protein corresponding to the first four kringle domains of human plasminogen and a truncated form of the Angiostatin protein, kringles 1-3. Purified recombinant Angiostatin K1-3 and K1-4 proteins inhibited the formation of experimental B16-BL6 lung metastases by greater than 80% when administered at 30 nmol/kg/day. We demonstrate for the first time that Angiostatin protein, consisting of the first three kringle domains of human plasminogen, has in vivo biological activity in this assay indistinguishable from that of the full-length Angiostatin K1-4 protein and that the fourth kringle of plasminogen, when linked in sequence to K1-3, plays no direct role in the antitumor activity of Angiostatin.


Asunto(s)
Antineoplásicos/química , Kringles , Fragmentos de Péptidos/química , Plasminógeno/química , Secuencia de Aminoácidos , Inhibidores de la Angiogénesis/química , Inhibidores de la Angiogénesis/farmacología , Angiostatinas , Animales , Antineoplásicos/farmacología , Células CHO , Movimiento Celular/efectos de los fármacos , Cricetinae , Endotelio Vascular/efectos de los fármacos , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/prevención & control , Neoplasias Pulmonares/secundario , Ratones , Datos de Secuencia Molecular , Fragmentos de Péptidos/biosíntesis , Fragmentos de Péptidos/farmacología , Plasminógeno/biosíntesis , Plasminógeno/genética , Plasminógeno/farmacología , Proteínas Recombinantes/biosíntesis
11.
J Neurosci Res ; 57(2): 219-26, 1999 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10398299

RESUMEN

Inflammation and the associated release of inflammatory cytokines such as tumor necrosis factor alpha (TNFalpha) may be a component of neurodegenerative diseases associated with aging or chronic HIV-1 infection. Most of the neurons that are affected under these conditions require a constant supply of trophic factors such as nerve growth factor (NGF) for survival. NGF acts via binding to a specific tyrosine kinase receptor (TrkA). NGF also binds to the common neurotrophin receptor (p75(NTR)), a member of the TNFalpha receptor (TNFR-I) superfamily, whose function may be to modulate apoptosis via the release of ceramide and the activation of the transcription factor nuclear factor kappa B (NFkappaB). The similarity between p75(NTR) and TNFR-I signal transduction pathways suggests that one of the mechanisms by which TNFalpha affects neuronal survival is by impacting upon these pathways that normally promote NGF support of neurons. Here we show that arachidonic acid (AA), a signaling lipid potentially associated with TNFR-I signal cascade, induces apoptosis in PC12 cells through inhibition of both protein kinase C zeta (PKCzeta) and NFkappaB activity. We also show that apoptosis induced by AA cannot be prevented by NGF. These data support the idea that PKCzeta and NFkappaB are both essential signaling elements for mediating NGF-promoted rescue from apoptosis. Our results also suggest that AA, an inflammatory signal lipid induced by TNFalpha via binding to TNFR-I, may reduce neuronal survival by inhibiting elements of the signal cascade induced by NGF.


Asunto(s)
Apoptosis/efectos de los fármacos , Ácido Araquidónico/farmacología , FN-kappa B/metabolismo , Factores de Crecimiento Nervioso/farmacología , Neuronas/enzimología , Proteína Quinasa C/metabolismo , Animales , Western Blotting , Supervivencia Celular/efectos de los fármacos , Medio de Cultivo Libre de Suero/farmacología , Fragmentación del ADN , Densitometría , Activación Enzimática/fisiología , Procesamiento de Imagen Asistido por Computador , L-Lactato Deshidrogenasa/metabolismo , Neuronas/citología , Células PC12 , Proteína Quinasa C/análisis , Ratas , Factor de Necrosis Tumoral alfa/farmacología
12.
Biochem Soc Symp ; 63: 261-71, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9513729

RESUMEN

The nm23 genes were discovered on the basis of their reduced expression by highly metastatic cell lines. This trend was confirmed in cohorts of several types of human carcinomas and melanomas. Several transfection studies have demonstrated the suppressive effect of nm23 overexpression on the metastatic aggressiveness of melanoma and breast carcinoma cells in vivo. These transfection experiments have also demonstrated an effect of nm23 overexpression on cellular functions involved in the metastatic phenotype, such as cell motility, and point to a regulatory role for Nm23 proteins in cellular signalling pathways. Nm23 homologues from various species are also involved in normal tissue development and differentiation. Transfection of nm23-H1 into breast cancer cells provided a functional demonstration of the involvement of this gene in the differentiation of mammary epithelial cells. However, the molecular mechanism of these biological effects remains unknown. Several biochemical activities have been reported for Nm23, including NDP kinase activity, serine autophosphorylation and protein-histidine kinase activity. To define the possible significance of these biochemical activities, we carried out site-directed mutagenesis of the relevant codons of nm23-H1 cDNA and studied the effects upon transfection into MDA-MB-435 human breast carcinoma cells. We have also used Nm23 expression as a molecular marker to identify novel compounds that are active against the most aggressive tumour cells. This approach revealed that none of the standard agents currently in clinical use is preferentially active against the most aggressive tumour cells, and allowed us to identify new compounds that are preferentially inhibitory towards low-Nm23-expressing breast carcinoma and melanoma cell lines. This analysis also revealed a significant correlation between Nm23 levels and sensitivity of the tumour cells to alkylating agents. A functional implication of Nm23 proteins in this phenomenon was demonstrated after transfection of nm23 cDNAs into melanoma and breast and ovarian carcinoma cells.


Asunto(s)
Proteínas de Unión al GTP Monoméricas , Metástasis de la Neoplasia/genética , Nucleósido-Difosfato Quinasa , Factores de Transcripción/genética , Secuencia de Aminoácidos , Animales , Neoplasias de la Mama/genética , Diferenciación Celular , Crecimiento , Humanos , Melanoma/genética , Datos de Secuencia Molecular , Nucleósido Difosfato Quinasas NM23 , Factores de Transcripción/química , Factores de Transcripción/fisiología , Transfección
13.
J Biol Chem ; 272(36): 22526-30, 1997 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-9278405

RESUMEN

Decreased levels of the nm23 gene product have been correlated with increased tumor metastatic potential in a variety of malignancies. At least a subset of the regulatory properties of Nm23 has been proposed to be due to transactivation of the human c-myc oncogene through binding to a homopyrimidine tract 140 base pairs upstream of the transcription start site (termed the CT element or the PuF site). Conventional transcription factors possess DNA binding and transactivation domains; Nm23 fusion proteins were used to address two questions. First, if provided with a well characterized DNA binding domain, does Nm23 possess a transactivation domain capable of stimulating transcription of an appropriate reporter? Second, if provided with a potent transactivation domain, is the DNA binding of Nm23 of sufficient specificity and affinity to direct the fusion protein to a CT-dependent reporter? Since reporter gene expression was not stimulated in either case, we conclude that Nm23 does not directly stimulate transcription through binding to the CT element and that its antimetastatic and other reported functions are likely due to other biochemical activities.


Asunto(s)
Proteínas de Unión al GTP Monoméricas , Nucleósido-Difosfato Quinasa , Proteínas de Saccharomyces cerevisiae , Factores de Transcripción/metabolismo , Activación Transcripcional , Animales , Células COS , Proteínas de Unión al ADN , Genes myc , Células HeLa , Humanos , Nucleósido Difosfato Quinasas NM23 , Regiones Promotoras Genéticas
14.
J Biol Chem ; 272(9): 5525-32, 1997 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-9038158

RESUMEN

We previously compared the structure and motility suppressive capacity of nm23-H1 by transfection of wild type and site-directed mutant forms into breast carcinoma cells. Wild type nm23-H1 and an nm23-H1(S44A) (serine 44 to alanine) mutant suppressed motility, whereas the nm23-H1(P96S), nm23-H1(S120G), and to a lesser extent, nm23-H1(S120A) mutant forms failed to do so. In the present study wild type and mutant recombinant Nm23-H1 proteins have been produced, purified, and assayed for phosphorylation and phosphotransfer activities. We report the first association of Nm23-H1 mutations lacking motility suppressive capacity with decreased in vitro activity in histidine-dependent protein phosphotransferase assays. Nm23-H1(P96S), a Drosophila developmental mutation homolog, exhibited normal autophosphorylation and nucleoside-diphosphate kinase (NDPK) characteristics but deficient phosphotransfer activity in three histidine protein kinase assays, using succinic thiokinase, Nm23-H2, and GST-Nm23-H1 as substrates. Nm23-H1(S120G), found in advanced human neuroblastomas, exhibited deficient activity in several histidine-dependent protein phosphotransfer reactions, including histidine autophosphorylation, downstream phosphorylation on serines, and slightly decreased histidine protein kinase activity; significant NDPK activity was observed. The Nm23-H1(S120A) mutant was deficient in only histidine-dependent serine autophosphorylation. Nm23-H1 and Nm23-H1(S44A) exhibited normal activity in all assays conducted. Based on this correlation, we hypothesize that a histidine-dependent protein phosphotransfer activity of Nm23-H1 may be responsible for its biological suppressive effects.


Asunto(s)
Proteínas de Unión al GTP Monoméricas , Nucleósido-Difosfato Quinasa/metabolismo , Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato/metabolismo , Factores de Transcripción/genética , Relación Dosis-Respuesta a Droga , Glutatión Transferasa/metabolismo , Histidina , Histidina Quinasa , Humanos , Modelos Biológicos , Mutagénesis Sitio-Dirigida , Nucleósido Difosfato Quinasas NM23 , Fosforilación , Proteínas Quinasas/metabolismo , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Serina , Transfección
15.
J Biol Chem ; 271(41): 25107-16, 1996 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-8810265

RESUMEN

We report the first correlation of Nm23 sequence and its tumor metastasis-suppressive capacity using site-directed mutagenesis and an in vitro tumor cell motility assay. MDA-MB-435 human breast carcinoma cells were transfected with a control expression vector (pCMVBamneo), the vector containing the wild type nm23-H1, or the nm23-H1 vector encoding mutations at the following amino acids: serine 44, a phosphorylation site; proline 96, the k-pn mutation in the Drosophila nm23 homolog that causes developmental defects; histidine 118, involved in Nm23's nucleoside diphosphate kinase activity; and serine 120, a site of mutation in human neuroblastomas and phosphorylation. The wild type nm23-H1 transfectants were 44-98% less motile to serum and 86-99% less motile to autotaxin than control vector transfectants. The proline 96 k-pn, serine 120 to glycine, and to a lesser extent serine 120 to alanine mutant nm23-H1-transfected cell lines exhibited motility levels at or above the control transfectants, indicating that these mutations can abrogate the motility-suppressive phenotype of nm23-H1. No effect was observed on cellular proliferation, nor were the serine 44 to alanine nm23-H1 mutant transfectants motile, demonstrating the specificity of the data. The data identify the first structural motifs of nm23-H1 that influence its metastasis suppressive effect and suggest complex biochemical associations or activities in the Nm23 suppressive pathway.


Asunto(s)
Proteínas de Unión al GTP Monoméricas , Nucleósido-Difosfato Quinasa/metabolismo , Prolina , Serina , Factores de Transcripción/fisiología , Alanina , Secuencia de Aminoácidos , Animales , Neoplasias de la Mama , División Celular , Quimiotaxis , Drosophila , Femenino , Glicina , Histidina , Humanos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Nucleósido Difosfato Quinasas NM23 , Neuroblastoma/genética , Nucleósido-Difosfato Quinasa/biosíntesis , Fosforilación , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes/metabolismo , Factores de Transcripción/biosíntesis , Transfección , Células Tumorales Cultivadas
16.
Cancer Res ; 56(13): 2931-5, 1996 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-8674043

RESUMEN

We report a functional link between expression of the metastasis suppressor gene nm23 and cancer cell sensitivity to the alkylating agent cisplatin. Cisplatin was 2-15-fold more inhibitory to the growth in vitro of nm23 transfectants of the K-1735 TK murine melanoma, MDA-MB-435 human breast carcinoma, and OVCAR-3 human ovarian carcinoma cell lines as compared to matched control transfectants. Administration of a single dose of cisplatin i.v. after injection of control- or nm23-1-transfected K-1735 TK melanoma cells resulted in a more pronounced inhibition of pulmonary metastatic colonization by the nm23-1 transfectants. The mechanism of nm23-dependent sensitivity to cisplatin is unknown, but was correlated with increased formation of interstrand DNA cross-links in nm23-H1 transfected breast carcinoma cells. These data suggest that elevation of tumor cell nm23 expression may be considered as a potential therapeutic strategy in combination with cisplatin treatment.


Asunto(s)
Antineoplásicos Alquilantes/farmacología , Cisplatino/farmacología , Proteínas de Unión al GTP Monoméricas , Proteínas de Neoplasias/fisiología , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Nucleósido-Difosfato Quinasa , Factores de Transcripción/fisiología , Animales , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , División Celular/efectos de los fármacos , Reactivos de Enlaces Cruzados/farmacología , Daño del ADN , ADN de Neoplasias/efectos de los fármacos , ADN de Neoplasias/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Melanoma/tratamiento farmacológico , Melanoma/genética , Ratones , Nucleósido Difosfato Quinasas NM23 , Proteínas de Neoplasias/genética , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Factores de Transcripción/genética , Transfección , Células Tumorales Cultivadas/efectos de los fármacos
18.
J Urol ; 154(1): 278-82, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7776445

RESUMEN

Reduced expression of nm23 has been associated with increased metastases and decreased survival in a variety of malignancies. In the present study, the expression of nm23 was examined by Northern and Western blot analyses in a series of cell lines derived from patients with metastatic renal cell carcinoma. Two of twelve (17%) informative cell lines derived from 9 patients had loss of heterozygosity at Nm23-H1. Twenty-two renal cancer cell lines derived from primary tumors, 5 cell lines derived from metastatic tumors and 4 short-term cultures of normal proximal renal tubular cells all expressed Nm23 mRNA in varying amounts. On average, the level of expression of Nm23 mRNA in short-term cultures of benign proximal renal tubular cells was found to be similar to the level seen in renal cancer cell lines. Twenty-eight cell lines derived from renal primary tumors and 8 cell lines derived from metastatic tumors expressed both the Nm23-H1 and Nm23-H2 proteins. High or low relative expression of nm23 at the mRNA or protein level did not correlate with survival. The absence of any anomalous pattern of expression of the nm23 genes and the lack of correlation of expression with survival suggests that nm23 does not play a central role in the progression of this tumor type.


Asunto(s)
Carcinoma de Células Renales/genética , Carcinoma de Células Renales/secundario , Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor/genética , Neoplasias Renales/genética , Proteínas de Unión al GTP Monoméricas , Nucleósido-Difosfato Quinasa/genética , Northern Blotting , Western Blotting , Carcinoma de Células Renales/enzimología , Línea Celular , Deleción Cromosómica , ADN de Neoplasias/análisis , ADN de Neoplasias/genética , Heterocigoto , Homocigoto , Humanos , Neoplasias Renales/enzimología , Túbulos Renales/enzimología , Túbulos Renales/metabolismo , Nucleósido Difosfato Quinasas NM23 , Nucleósido-Difosfato Quinasa/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Tasa de Supervivencia , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Células Tumorales Cultivadas
19.
Eur J Cancer ; 31A(7-8): 1096-100, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7576999

RESUMEN

The majority of cancer patients succumb to the consequences of metastatic disease. A correlation of increased nm23 expression to low metastatic potential has been established in several malignancies, based on published prognostic studies with tumour cohorts and transfection studies. Transfection of highly metastatic MDA-MB-435 human breast carcinoma cells with nm23-H1 cDNA resulted in a significant reduction in the metastatic potential in vivo. These transfections also showed inhibition of colonisation and motility, as well as morphological and biosynthetic differentiation in vitro. The biochemical mechanism of Nm23-H1 action, as well as the identity of proteins involved in its functional biochemical pathway, are still unknown. We summarise published and recent research concerning the role of the nm23 gene in metastasis and normal cellular differentiation.


Asunto(s)
Proteínas de Unión al GTP Monoméricas , Metástasis de la Neoplasia , Proteínas de Neoplasias/fisiología , Factores de Transcripción/fisiología , Animales , Neoplasias de la Mama/genética , Diferenciación Celular/genética , Expresión Génica , Humanos , Ratones , Nucleósido Difosfato Quinasas NM23 , Metástasis de la Neoplasia/genética , Proteínas de Neoplasias/genética , Nucleósido-Difosfato Quinasa/fisiología , Factores de Transcripción/genética , Transfección
20.
Lancet ; 344(8921): 547-8, 1994 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-7914643
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