RESUMEN
OBJECTIVE: This study aimed to evaluate the efficacy and safety of direct oral anticoagulants (DOACs) versus warfarin in patients with antiphospholipid syndrome (APS). METHODS: We performed a literature search using MEDLINE, EMBASE, and the Cochrane Controlled Trials Register. We also performed a meta-analysis of randomized controlled trials (RCTs) investigating the effectiveness and safety of DOACs versus warfarin in patients with APS. RESULTS: Five RCTs involving 648 patients with APS (330 in DOAC-treated and 318 in control groups) were included in the meta-analysis. Among the patients included in the analysis, 29 (8.8%) patients experienced recurrent thrombosis in the DOAC treatment group, and 10 patients (3.1%) had thrombosis recurrence in the warfarin treatment group, resulting in a higher incidence in DOAC-treated than in the warfarin-treated groups [odds ratio (OR) = 2.163, 95% CI = 0.985-4.748, p = 0.055]. Incidence of arterial thrombosis was significantly higher in DOAC-treated patients than in warfarin-treated patients (OR = 5.168, 95% CI = 1.567-17.04, p = 0.007). Stroke and thrombosis occurrences were significantly higher in the triple positivity group than in the warfarin therapy group (OR = 12.03, 95% CI = 2.249-64.36, p = 0.004; OR = 2.940, 95% CI = 1.016-8.504, p = 0.047). However, venous thrombosis occurrences did not differ significantly between the DOAC-treated and warfarin-treated groups. There were no significant differences between the DOAC and warfarin groups in terms of any bleeding, major bleeding, minor bleeding, and all-cause mortality. CONCLUSION: DOACs were associated with higher rates of arterial thrombosis than warfarin in patients with APS, especially in the triple-positive group. However, a higher risk of recurrent venous thrombosis was not found in APS patients treated with DOACs compared to those treated with warfarin.
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Síndrome Antifosfolípido , Lupus Eritematoso Sistémico , Trombosis , Administración Oral , Anticoagulantes/efectos adversos , Síndrome Antifosfolípido/inducido químicamente , Síndrome Antifosfolípido/complicaciones , Síndrome Antifosfolípido/tratamiento farmacológico , Humanos , Lupus Eritematoso Sistémico/complicaciones , Ensayos Clínicos Controlados Aleatorios como Asunto , Trombosis/epidemiología , Trombosis/etiología , Trombosis/prevención & control , Warfarina/efectos adversosRESUMEN
Renal cell carcinoma (RCC) is not a single disease but is made up of several different histologically defined subtypes that are associated with distinct genetic alterations which require subtype specific management and treatment. Papillary renal cell carcinoma (pRCC) is the second most common subtype after conventional/clear cell RCC (ccRCC), representing ~20% of cases, and is subcategorized into type 1 and type 2 pRCC. It is important for preclinical studies to have cell lines that accurately represent each specific RCC subtype. This study characterizes seven cell lines derived from both primary and metastatic sites of type 1 pRCC, including the first cell line derived from a hereditary papillary renal carcinoma (HPRC)-associated tumor. Complete or partial gain of chromosome 7 was observed in all cell lines and other common gains of chromosomes 16, 17, or 20 were seen in several cell lines. Activating mutations of MET were present in three cell lines that all demonstrated increased MET phosphorylation in response to HGF and abrogation of MET phosphorylation in response to MET inhibitors. CDKN2A loss due to mutation or gene deletion, associated with poor outcomes in type 1 pRCC patients, was observed in all cell line models. Six cell lines formed tumor xenografts in athymic nude mice and thus provide in vivo models of type 1 pRCC. These type 1 pRCC cell lines provide a comprehensive representation of the genetic alterations associated with pRCC that will give insight into the biology of this disease and be ideal preclinical models for therapeutic studies.
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Carcinoma de Células Renales/genética , Autenticación de Línea Celular/métodos , Neoplasias Renales/genética , Ensayos Antitumor por Modelo de Xenoinjerto/métodos , Animales , Carcinoma de Células Renales/patología , Línea Celular Tumoral , Inestabilidad Cromosómica , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Humanos , Neoplasias Renales/patología , Ratones , Mutación , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismoRESUMEN
The vascular endothelial growth factor (VEGF)/VEGFR and hepatocyte growth factor (HGF)/c-MET signaling pathways act synergistically to promote angiogenesis. Studies indicate VEGF inhibition leads to increased levels of phosphorylated c-MET, bypassing VEGF-mediated angiogenesis and leading to chemoresistance. We conducted a phase 1 clinical trial with 32 patients with refractory solid tumors to evaluate the safety, pharmacokinetics, and pharmacodynamics of combinations of VEGF-targeting pazopanib and the putative c-MET inhibitor ARQ197 (tivantinib) at 5 dose levels (DLs). Patients either took pazopanib and tivantinib from treatment initiation (escalation phase) or pazopanib alone for 7 days, with paired tumor sampling, prior to starting combination treatment (expansion phase). Hypertension was the most common adverse event. No more than 1 dose limiting toxicity (DLT) occurred at any DL, so the maximum tolerated dose (MTD) was not determined; DL5 (800 mg pazopanib daily and 360 mg tivantinib BID) was used during the expansion phase. Twenty of 31 evaluable patients achieved stable disease lasting up to 22 cycles. Circulating VEGF, VEGFR2, HGF, and c-MET levels were assessed, and only VEGF levels increased. Tumor c-MET levels (total and phosphorylated) were determined in paired biopsies before and after 7 days of pazopanib treatment. Total intact c-MET decreased in 6 of 7 biopsy pairs, in contrast to previously reported c-MET elevation in response to VEGF inhibition. These results are discussed in the context of our previously reported analysis of epithelial-mesenchymal transition in these tumors.
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Inhibidores de la Angiogénesis/uso terapéutico , Indazoles/uso terapéutico , Neoplasias/tratamiento farmacológico , Pirimidinas/uso terapéutico , Pirrolidinonas/uso terapéutico , Quinolinas/uso terapéutico , Sulfonamidas/uso terapéutico , Inhibidores de la Angiogénesis/administración & dosificación , Inhibidores de la Angiogénesis/efectos adversos , Inhibidores de la Angiogénesis/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Factor de Crecimiento de Hepatocito/metabolismo , Humanos , Indazoles/administración & dosificación , Indazoles/efectos adversos , Indazoles/farmacocinética , Dosis Máxima Tolerada , Persona de Mediana Edad , Neoplasias/patología , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Pirimidinas/administración & dosificación , Pirimidinas/efectos adversos , Pirimidinas/farmacocinética , Pirrolidinonas/administración & dosificación , Pirrolidinonas/efectos adversos , Pirrolidinonas/farmacocinética , Quinolinas/administración & dosificación , Quinolinas/efectos adversos , Quinolinas/farmacocinética , Sulfonamidas/administración & dosificación , Sulfonamidas/efectos adversos , Sulfonamidas/farmacocinética , Factor A de Crecimiento Endotelial Vascular/efectos de los fármacosRESUMEN
Hepatocyte growth factor (HGF)-induced activation of its cell surface receptor, the Met tyrosine kinase, drives mitogenesis, motogenesis and morphogenesis in a wide spectrum of target cell types and embryologic, developmental and homeostatic contexts. Typical paracrine HGF/Met signaling is regulated by HGF activation at target cell surfaces, HGF binding-induced receptor activation, internalization and degradation. Despite these controls, HGF/Met signaling contributes to oncogenesis, tumor angiogenesis and invasiveness, and tumor metastasis in many types of cancer, leading to the rapid growth of pathway-targeted anticancer drug development programs. We review here HGF and Met structure and function, basic properties of HGF/Met pathway antagonists now in clinical development, and recent clinical trial results. Presently, the main challenges facing the effective use of HGF/Met-targeted antagonists for cancer treatment include optimal patient selection, diagnostic and pharmacodynamic biomarker development, and the identification and testing of effective therapy combinations. The wealth of basic information, analytical reagents and model systems available regarding normal and oncogenic HGF/Met signaling will continue to be invaluable in meeting these challenges and moving expeditiously toward more effective cancer treatment.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Factor de Crecimiento de Hepatocito/antagonistas & inhibidores , Modelos Biológicos , Terapia Molecular Dirigida , Neoplasias/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Animales , Antineoplásicos/uso terapéutico , Factor de Crecimiento de Hepatocito/química , Factor de Crecimiento de Hepatocito/genética , Factor de Crecimiento de Hepatocito/metabolismo , Humanos , Terapia Molecular Dirigida/tendencias , Mutación , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Conformación Proteica , Proteínas Proto-Oncogénicas c-met/química , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismoRESUMEN
Glucagon plays important roles in normal glucose homeostasis and in metabolic abnormalities, particularly diabetes. Glucagon excess, rather than insulin deficiency, is essential for the development of diabetes for several reasons. Glucagon increases hepatic glucose and ketone production, the catabolic features of insulin deficiency. Hyperglucagonaemia is present in every form of diabetes. Beta cell destruction in glucagon receptor null mice does not cause diabetes unless mice are administered adenovirus encoding the glucagon receptor. In rodent studies the glucagon suppressors leptin and glucagon receptor antibody suppressed all catabolic manifestations of diabetes during insulin deficiency. Insulin prevents hyperglycaemia; however, insulin monotherapy cannot cure diabetes such that non-diabetic glucose homeostasis is achieved. Glucose-responsive beta cells normally regulate alpha cells, and diminished insulin action on alpha cells will favour hypersecretion of glucagon by the alpha cells, thus altering the insulin:glucagon ratio. Treating diabetes by suppression of glucagon, with leptin or antibody against the glucagon receptor, normalised glucose level (without glycaemic volatility) and HbA1c. Glucagon suppression also improved insulin sensitivity and glucose tolerance. If these results can be translated to humans, suppression of glucagon action will represent a step forward in the treatment of diabetes. This review summarises a presentation given at the 'Novel data on glucagon' symposium at the 2015 annual meeting of the EASD. It is accompanied by two other reviews on topics from this symposium (by Mona Abraham and Tony Lam, DOI: 10.1007/s00125-016-3950-3 , and by Russell Miller and Morris Birnbaum, DOI: 10.1007/s00125-016-3955-y ) and an overview by the Session Chair, Isabel Valverde (DOI: 10.1007/s00125-016-3946-z ).
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Diabetes Mellitus/metabolismo , Diabetes Mellitus/patología , Glucagón/metabolismo , Animales , Hemoglobina Glucada/metabolismo , Humanos , Insulina/metabolismo , RatonesAsunto(s)
Alendronato , Osteoporosis , Anticuerpos Monoclonales , Femenino , Fracturas Óseas , HumanosRESUMEN
Hepatocyte growth factor (HGF) signaling promotes tumor invasiveness in renal cell carcinoma (RCC) and other cancers. In clear cell RCC, VHL loss generates pseudohypoxia that exacerbates HGF-driven invasion through ß-catenin deregulation. Hypoxia also enhances HGF-driven invasiveness by papillary RCC cells, but in the absence of VHL, loss signaling integration involves three parallel routes: 1) hypoxia-induced reactive oxygen species production and decreased DUSP2 expression, leading to enhanced mitogen-activated protein kinase (MAPK) cascade activation; 2) reactive oxygen species-induced diacylglycerol production by phospholipase Cγ, leading to protein kinase C activation and increased protein phosphatase- 2A activity, thereby suppressing HGF-induced Akt activation; and 3) a profound shift from HGF-enhanced, proliferation- oriented metabolism to autophagy-dependent invasion and suppression of proliferation. This tripartite signaling integration was not unique to RCC or HGF; in RCC cells, invasive synergy induced by the combination of hypoxia and epidermal growth factor occurred through the same mechanism, and in estrogen receptor-positive breast cancer cells, this mechanism was suppressed in the absence of estrogen. These results define the molecular basis of growth factor and hypoxia invasive synergy in VHL-competent papillary RCC cells, illustrate the plasticity of invasive and proliferative tumor cell states, and provide signaling profiles by which they may be predicted.
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Neoplasias de la Mama/metabolismo , Carcinoma de Células Renales/metabolismo , Factor de Crecimiento de Hepatocito/metabolismo , Neoplasias Renales/metabolismo , Sistema de Señalización de MAP Quinasas , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Hipoxia de la Célula/genética , Línea Celular Tumoral , Fosfatasa 2 de Especificidad Dual/genética , Fosfatasa 2 de Especificidad Dual/metabolismo , Femenino , Regulación Enzimológica de la Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/genética , Factor de Crecimiento de Hepatocito/genética , Humanos , Neoplasias Renales/genética , Neoplasias Renales/patología , Invasividad Neoplásica , Proteína Quinasa C/genética , Proteína Quinasa C/metabolismo , Proteína Fosfatasa 2/genética , Proteína Fosfatasa 2/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismoRESUMEN
BACKGROUND: The duration of oral antibiotic acne therapy for adolescents compared with guidelines was recently investigated; however it was uncertain if duration of antibiotics for adult acne therapy differed. OBJECTIVE: This study aimed to evaluate duration of oral antibiotics for adult acne compared with guidelines and determine possible cost-savings. METHODS: This was a retrospective cohort study of MarketScan Commercial Claims and Encounters database that incorporated claims data to determine duration and costs of antibiotic treatment among adults ages 21 years and older. RESULTS: Of 17,448 courses, 84.5% (14,737) aligned with duration guidelines, although 12,040 (69.0%) courses did not include concomitant topical retinoid therapy. Mean savings of $592.26 per person could result if prolonged courses met guidelines. Mean (median) costs of generic and branded formulations for the most frequent course duration (90-179 days) were $103.77 ($54.27) and $1421.61 ($1462.25), respectively. LIMITATIONS: Actual patient prescription adherence is uncertain and database lacks information regarding acne severity, patient physical characteristics, and clinical outcomes. CONCLUSIONS: The majority of oral antibiotic course durations follow guidelines, although topical retinoids are underused. Costs of antibiotic therapy were lower for shorter courses and those using generic medications; the cost-effectiveness of these modifications has not been investigated.
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Acné Vulgar/tratamiento farmacológico , Antibacterianos/administración & dosificación , Guías de Práctica Clínica como Asunto , Administración Oral , Adolescente , Adulto , Antibacterianos/economía , Estudios de Cohortes , Ahorro de Costo , Femenino , Humanos , Masculino , Estudios RetrospectivosRESUMEN
BACKGROUND: Duration of oral antibiotic therapy in acne has not been widely studied. Recent guidelines suggest it should be limited to 3 to 6 months. OBJECTIVE: We sought to compare the duration of oral antibiotic use with recent guidelines and determine the potential cost-savings related to shortened durations. METHODS: This is a retrospective cohort study from the MarketScan Commercial Claims and Encounters database. Claims data were used to determine duration and costs of antibiotic therapy. RESULTS: The mean course duration was 129 days. The majority (93%) of courses were less than 9 months. Among the 31,634 courses, 18,280 (57.8%) did not include concomitant topical retinoid therapy. The mean (95% confidence interval) duration with and without topical retinoid use was 133 (131.5-134.7) days and 127 (125.4-127.9) days, respectively. The mean excess direct cost of antibiotic treatment for longer than 6 months was $580.99/person. LIMITATIONS: Claims cannot be attributed to a specific diagnosis or provider. The database does not provide information on acne severity. CONCLUSIONS: Duration of antibiotic use is decreasing when compared with previous data. However, 5547 (17.53%) courses exceeded 6 months, highlighting an opportunity for reduced antibiotic use. If courses greater than 6 months were shortened to 6 months, savings would be $580.99/person.
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Acné Vulgar/tratamiento farmacológico , Antibacterianos/administración & dosificación , Pautas de la Práctica en Medicina , Acné Vulgar/economía , Administración Oral , Adolescente , Antibacterianos/economía , Ahorro de Costo , Costo de Enfermedad , Dermatología/normas , Femenino , Humanos , Masculino , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Medicina/economía , Pautas de la Práctica en Medicina/normas , Estudios Retrospectivos , Adulto JovenRESUMEN
We conducted an experimental investigation to examine the immiscible radial displacement flows of air invading three-dimensional foam in a Hele-Shaw cell. Our study successfully identified three distinct flow regimes. In the initial regime, characterized by relatively low fingertip velocities, the foam underwent a slow displacement through plug flow. During this process, the three-phase contact lines slipped at the cell walls. Notably, we discovered that the air injection pressure exhibited a proportional relationship with the power of the fingertip velocity. This relationship demonstrated excellent agreement with a power law, where the exponent was determined to be 2/3. Transitioning to the second regime, we observed relatively high velocities, resulting in the displacement of the foam as a plug within single layers of foam bubbles. The movement of these bubbles near the cell walls was notably slower. Similar to the first regime, the behavior in this regime also adhered to a power law. In the third regime, which manifested at higher air injection pressures, the development of air fingers occurred through narrow channels. These channels had the potential to isolate the air fingers as they underwent a process of "healing." Furthermore, our results unveiled a significant finding that the width of the air fingers exhibited a continuous scaling with the air injection pressure, irrespective of the flow regimes being observed.
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Drug resistance is a long-standing impediment to effective systemic cancer therapy and acquired drug resistance is a growing problem for molecularly-targeted therapeutics that otherwise have shown unprecedented successes in disease control. The hepatocyte growth factor (HGF)/Met receptor pathway signaling is frequently involved in cancer and has been a subject of targeted drug development for nearly 30 years. To anticipate and study specific resistance mechanisms associated with targeting this pathway, we engineered resistance to the HGF-neutralizing antibody rilotumumab in glioblastoma cells harboring autocrine HGF/Met signaling, a frequent abnormality of this brain cancer in humans. We found that rilotumumab resistance was acquired through an unusual mechanism comprising dramatic HGF overproduction and misfolding, endoplasmic reticulum (ER) stress-response signaling and redirected vesicular trafficking that effectively sequestered rilotumumab and misfolded HGF from native HGF and activated Met. Amplification of MET and HGF genes, with evidence of rapidly acquired intron-less, reverse-transcribed copies in DNA, was also observed. These changes enabled persistent Met pathway activation and improved cell survival under stress conditions. Point mutations in the HGF pathway or other complementary or downstream growth regulatory cascades that are frequently associated with targeted drug resistance in other prevalent cancer types were not observed. Although resistant cells were significantly more malignant, they retained sensitivity to Met kinase inhibition and acquired sensitivity to inhibition of ER stress signaling and cholesterol biosynthesis. Defining this mechanism reveals details of a rapidly acquired yet highly-orchestrated multisystem route of resistance to a selective molecularly-targeted agent and suggests strategies for early detection and effective intervention.
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Abnormal accumulation and activation of the recepteur d'origine nantais (RON) has been implicated in carcinogenesis of epithelial tumors. RON expression was induced by the tumor promoter, phorbol 12-myristate 13-acetate (PMA), in gastric adenocarcinoma AGS cells. Studies with deleted and site-directed mutagenesis of Egr-1 promoter and with expression vectors encoding Egr-1 confirmed that Egr-1 is essential for RON expression. In addition, AGS cells pretreated with PMA showed remarkably enhanced invasiveness, which was partially abrogated by siRNA-targeted RON and Egr-1. These results suggest that tumor promoter induces RON expression via Egr-1, which, in turn, stimulates cell invasiveness in AGS cells.
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Adenocarcinoma/patología , Proteína 1 de la Respuesta de Crecimiento Precoz/fisiología , Invasividad Neoplásica , Proteínas Tirosina Quinasas Receptoras/metabolismo , Neoplasias Gástricas/patología , Regulación hacia Arriba , Adenocarcinoma/enzimología , Adenocarcinoma/metabolismo , Secuencia de Bases , Western Blotting , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , Cartilla de ADN , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Humanos , Mutagénesis Sitio-Dirigida , Regiones Promotoras Genéticas , ARN Interferente Pequeño/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Gástricas/enzimología , Neoplasias Gástricas/metabolismoRESUMEN
Angiotensin II (Ang II) is a key proapoptotic factor in fibrotic tissue diseases. However, the mechanism of Ang-II-induced cell death in endothelial cells has not been previously elucidated. Using the neutral comet assay and specific receptor antagonists and agonists, we found that Ang-II-mediated apoptosis in primary pulmonary endothelial cells required the AT2 receptor. Ang II caused cytochrome c release from the mitochondria concurrent with caspase-3 activation and DNA fragmentation, and apoptosis was suppressed by an inhibitor of Bax-protein channel formation, implicating mitochondrial-mediated apoptosis. There was no evidence that the extrinsic apoptotic pathway was involved, because caspase-9, but not caspase-8, was activated by Ang-II treatment. Apoptosis required phosphoprotein phosphatase activation, and inhibition of the SHP-2 phosphatase (encoded by Ptpn11) blocked cell death. Reduced levels of anti-apoptotic Bcl-2-family members can initiate intrinsic apoptosis, and we found that Ang-II treatment lowered cytosolic Bcl-x(L) protein levels. Because the protein nucleolin has been demonstrated to bind Bcl-x(L) mRNA and prevent its degradation, we investigated the role of nucleolin in Ang-II-induced loss of Bcl-x(L). RNA-immunoprecipitation experiments revealed that Ang II reduced the binding of nucleolin to Bcl-x(L) mRNA in an AU-rich region implicated in instability of Bcl-x(L) mRNA. Inhibition of SHP-2 prevented Ang-II-induced degradation of Bcl-x(L) mRNA. Taken together, our findings suggest that nucleolin is a primary target of Ang-II signaling, and that Ang-II-activated SHP-2 inhibits nucleolin binding to Bcl-x(L) mRNA, thus affecting the equilibrium between pro- and anti-apoptotic members of the Bcl-2 family.
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Angiotensina II/farmacología , Células Endoteliales/efectos de los fármacos , Fosfoproteínas/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Fibrosis Pulmonar/metabolismo , Proteínas de Unión al ARN/metabolismo , Animales , Apoptosis , Caspasas/metabolismo , Bovinos , Células Cultivadas , Citocromos c/metabolismo , Células Endoteliales/metabolismo , Células Endoteliales/patología , Activación Enzimática/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Arteria Pulmonar/patología , Fibrosis Pulmonar/genética , Fibrosis Pulmonar/patología , Receptor de Angiotensina Tipo 2/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína bcl-X/biosíntesis , Proteína bcl-X/genética , NucleolinaRESUMEN
Two vascular endothelial growth factor (VEGF) receptors, FLT-1 and KDR, are expressed preferentially in proliferating endothelium. There is increasing evidence that recombinant, soluble VEGF receptor domains interfering with VEGF signaling may inhibit in vivo neoangiogenesis, tumor growth and metastatic spread. We hypothesized that a soluble form of FLT-1 receptor (sFLT-1) could inhibit the growth of pre-established tumors via an anti-angiogenic mechanism. A replication-deficient adenovirus (Ad) vector carrying the sflt-1 cDNA (Adsflt) was used to overexpress the sFLT-1 receptor in a breast cancer animal model. MCF-7 cells, which produce VEGF, were used to establish solid tumors in the mammary fat pads of female nude mice. After six weeks, tumors were injected either with Adsflt or a negative control virus (AdCMV.ßgal). After six months, average tumor volume in the Adsflt-infected group (33 ± 22 mm3) decreased by 91% relative to that of the negative control group (388 ± 94 mm3; p < 0.05). Moreover, 10 of 15 Adsflt-infected tumors exhibited complete regression. The vascular density of Adsflt-infected tumors was reduced by 50% relative to that of negative controls (p < 0.05), which is consistent with sFLT-1-mediated tumor regression through an anti-angiogenic mechanism. Moreover, cell necrosis and fibrosis associated with long-term regression of Adsflt−infected tumors were preceded by apoptosis of tumor vascular endothelial cells. Mice treated with Adsflt intratumorally showed no delay in the healing of cutaneous wounds, providing preliminary evidence that Ad-mediated sFLT-1 overexpression may be an effective anti-angiogenic therapy for cancer without the risk of systemic anti-angiogenic effects.
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At the cellular level, 5'-AMP-activated protein kinase (AMPK) serves as a critical link between energy homeostasis and the regulation of fundamental biological activities, including apoptosis. Angiotensin (Ang) II plays a key role in fibrotic lung remodeling. We recently demonstrated that Ang II induces apoptosis in pulmonary artery endothelial cells (PAEC) through the Ang type 2 receptor (AT(2)). AT(2) activates Src-homology two-domain-containing phosphatase-2 (SHP-2) in a signaling cascade leading to Bcl-x(L) mRNA destabilization and initiation of intrinsic apoptosis. We investigated the requirement of AMPK and ATP generation for Ang II-induced apoptosis in PAEC. Ang II activated AMPK, which was required for ATP generation. Inhibition of ATP production by compound C, an AMPK inhibitor, or by oligomycin suppressed Ang II-induced apoptosis. Experiments in Chinese hamster ovary-K1 cells expressing ectopic AT(2) (wild-type, mutant D90A, or carboxy terminal truncated mutant tC319) demonstrated that AT(2) activation of AMPK required the active conformation of the receptor and the carboxy terminal 44 amino acids. AMPK associated with and activated SHP-2 and was required for Bcl-x(L) mRNA destabilization. These are the first findings demonstrating that AMPK is activated by Ang II to produce ATP required for apoptosis. Our data also indicate that AMPK plays an energy-independent role by mediating SHP-2 activation.
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Proteínas Quinasas Activadas por AMP/metabolismo , Adenosina Trifosfato/biosíntesis , Angiotensina II/farmacología , Células Endoteliales/metabolismo , Activación Enzimática/efectos de los fármacos , Arteria Pulmonar/metabolismo , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/genética , Animales , Apoptosis/efectos de los fármacos , Western Blotting , Bovinos , Cricetinae , Cricetulus , Células Endoteliales/citología , Mutación , Plásmidos , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Arteria Pulmonar/citología , Receptor de Angiotensina Tipo 2/genética , Receptor de Angiotensina Tipo 2/metabolismo , Transducción de Señal/fisiología , Transfección , Proteína bcl-X/genética , Proteína bcl-X/metabolismo , Dominios Homologos srcRESUMEN
Scleromyxedema is a systemic disease characterized by lichenoid papules, nodules, and plaques on the skin and often diffuse skin induration resembling the cutaneous involvement of systemic sclerosis. The systemic involvement affects the musculoskeletal, pulmonary, cardiovascular, gastrointestinal, and central nervous systems, and the disorder is commonly associated with a paraproteinemia. Involvement of the kidney is rare and not considered a feature of the disease. Here, we describe an unusual case of scleromyxedema complicated by the development of scleroderma renal crisis-like acute renal failure with a marked intimal deposition of mucin, mucopolysaccharides, and hyaluronic acid in the intrarenal vessels.
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Lesión Renal Aguda/etiología , Lesión Renal Aguda/metabolismo , Glicosaminoglicanos/metabolismo , Arteria Renal/metabolismo , Venas Renales/metabolismo , Esclerodermia Sistémica/complicaciones , Escleromixedema/complicaciones , Lesión Renal Aguda/diagnóstico , Biopsia , Resultado Fatal , Femenino , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Riñón/patología , Persona de Mediana Edad , Esclerodermia Sistémica/diagnóstico , Esclerodermia Sistémica/tratamiento farmacológico , Escleromixedema/tratamiento farmacológico , Escleromixedema/metabolismoRESUMEN
Comprehensive characterizations of bladder cancer (BCa) have established molecular phenotype classes with distinct alterations and survival trends. Extending these studies within the tyrosine kinase (TK) family to identify disease drivers could improve our use of TK inhibitors to treat specific patient groups or individuals. We examined the expression distribution of TKs as a class (n = 89) in The Cancer Genome Atlas (TCGA) muscle invasive BCa data set (n >400). Patient profiles of potentially oncogenic alterations (overexpression and/or amplification) clustered TKs into 3 groups; alterations of group 1 and 3 TKs were associated with significantly worse patient survival relative to those without alterations. Many TK pathways induce epithelial-to-mesenchymal transition (EMT), which promotes tumor invasiveness and metastasis. Overexpression and/or amplification among 9 EMT transcriptional activators occurred in 43% of TCGA cases. Co-occurring alterations of TKs and EMT transcriptional activators involved most group 1 TKs; 24% of these events were associated with significantly worse patient survival. Co-occurring alterations of receptor TKs and their cognate ligands occurred in 16% of TCGA cases and several BCa-derived cell lines. Suppression of GAS6, MST1 or CSF1, or their respective receptors (AXL, MST1R and CSF1R), in BCa cell lines was associated with decreased receptor activation, cell migration, cell proliferation and anchorage independent cell growth. These studies reveal the patterns and prevalence of potentially oncogenic TK pathway-related alterations in BCa and identify specific alterations associated with reduced BCa patient survival. Detection of these features in BCa patients could better inform TK inhibitor use and improve clinical outcomes.
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Comunicación Autocrina , Proteínas Tirosina Quinasas Receptoras/metabolismo , Neoplasias de la Vejiga Urinaria/patología , Animales , Línea Celular Tumoral , Bases de Datos Factuales , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Estimación de Kaplan-Meier , Ratones , Invasividad Neoplásica , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/genética , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Trasplante Heterólogo , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/mortalidad , Tirosina Quinasa del Receptor AxlRESUMEN
BACKGROUND: Cell transdifferentiation is characterized by loss of some phenotypes along with acquisition of new phenotypes in differentiated cells. The differentiated state of a given cell is not irreversible. It depends on the up- and downregulation exerted by specific molecules. RESULTS: We report here that HCCR-1, previously shown to play an oncogenic role in human cancers, induces epithelial-to-mesenchymal transition (EMT) and mesenchymal-to-epithelial transition (MET) in human and mouse, respectively. The stem cell factor receptor CD117/c-Kit was induced in this transdifferentiated (EMT) sarcoma tissues. This MET occurring in HCCR-1 transfected cells is reminiscent of the transdifferentiation process during nephrogenesis. Indeed, expression of HCCR-1 was observed during the embryonic development of the kidney. This suggests that HCCR-1 might be involved in the transdifferentiation process of cancer stem cell. CONCLUSIONS: Therefore, we propose that HCCR-1 may be a regulatory factor that stimulates morphogenesis of epithelia or mesenchyme during neoplastic transformation.
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Transdiferenciación Celular , Transformación Celular Neoplásica , Riñón/metabolismo , Proteínas Proto-Oncogénicas c-kit/biosíntesis , Proteínas Proto-Oncogénicas/metabolismo , Animales , Clonación Molecular , Regulación del Desarrollo de la Expresión Génica , Humanos , Riñón/embriología , Riñón/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Células 3T3 NIH , Trasplante de Neoplasias , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-kit/genética , Transgenes/genéticaRESUMEN
Bleomycin, a chemotherapeutic agent, can cause pulmonary fibrosis in humans and is commonly used to induce experimental pulmonary fibrosis in rodents. In cell culture, bleomycin causes single- and double-stranded DNA breaks and produces reactive oxidative species, both of which require iron (Fe(2+)) and O(2). The mechanism of bleomycin-induced apoptosis is controversial due to its complexity. We investigated bleomycin apoptotic signaling events in primary pulmonary endothelial cells. Time course experiments revealed that bleomycin induced apoptosis within 4 h. Caspase-8, the initiator caspase for the extrinsic pathway, was activated within 2 h and preceded activation of the effector caspases-3 and -6 (4 h). Caspase-9, the initiator of the intrinsic pathway and release of cytochrome c from the mitochondria were not detected at these time points. Bleomycin induced the expression of Bcl-2 and Bcl-x(L), Bcl-2 family member proteins that protect cells from the mitochondria-dependent intrinsic apoptosis. Real-time quantitative RT-PCR results demonstrated that, at 4-8 h, bleomycin induced expression of TNF and TNF receptor family genes known to induce the extrinsic apoptotic pathway. Silencing of the death receptor adaptor protein Fas-associated death domain by short interfering RNA significantly reduced bleomycin-induced apoptosis. Apoptosis was also abrogated by caspase-8 inhibition, but only slightly reduced by caspase-3 inhibition. Together, these data suggest that bleomycin initiates apoptosis via the extrinsic pathway.
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Apoptosis/efectos de los fármacos , Bleomicina/toxicidad , Pulmón/efectos de los fármacos , Pulmón/patología , Animales , Apoptosis/genética , Secuencia de Bases , Inhibidores de Caspasas , Caspasas/genética , Caspasas/metabolismo , Bovinos , Células Cultivadas , Cartilla de ADN/genética , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Células Endoteliales/patología , Proteína de Dominio de Muerte Asociada a Fas/antagonistas & inhibidores , Proteína de Dominio de Muerte Asociada a Fas/genética , Proteína de Dominio de Muerte Asociada a Fas/metabolismo , Expresión Génica/efectos de los fármacos , Humanos , Pulmón/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismoRESUMEN
Hepatocyte growth factor (HGF) is critical for tissue homeostasis and repair in many organs including the lung, heart, kidney, liver, nervous system, and skin. HGF is a heterodimeric protein containing 20 disulfide bonds distributed among an amino-terminal hairpin, four kringle domains, and a serine protease-like domain. Due to its complex structure, recombinant production of HGF in prokaryotes requires denaturation and refolding, processes that are impractical for large-scale manufacture. Thus, pharmaceutical quantities of HGF are not available despite its potential applications. A fragment of the Listeria monocytogenes internalin B protein from amino acids 36-321 (InlB36â321) was demonstrated to bind to and partially activate the HGF receptor Met. InlB36â321 has a stable ß-sheet structure and is easily produced in its native conformation by Escherichia coli. We cloned InlB36â321 (1×InlB36â321) and engineered a head-to-tail repeat of InlB36â321 with a linker peptide (2×InlB36â321); 1×InlB36â321 and 2×InlB36â321 were purified from E. coli. Both 1× and 2×InlB36â321 activated the Met tyrosine kinase. We subsequently compared signal transduction of the two proteins in primary lung endothelial cells. 2×InlB36â321 activated ERK1/2, STAT3, and phosphatidylinositol 3-kinase/Akt pathways, whereas 1×InlB36â321 activated only STAT3 and ERK1/2. The 2×InlB36â321 promoted improved motility compared with 1×InlB36â321 and additionally stimulated proliferation equivalent to full-length HGF. Both the 1× and 2×InlB36â321 prevented apoptosis by the profibrotic peptide angiotensin II in cell culture and ex vivo lung slice cultures. The ease of large-scale production and capacity of 2×InlB36â321 to mimic HGF make it a potential candidate as a pharmaceutical agent for tissue repair.