RESUMEN
BACKGROUND: The optional periprocedural antithrombotic management for carotid artery stenting (CAS) is still debated. METHODS: We aimed to compare the procedural and 1-month outlook of patients undergoing CAS with tirofiban as parenteral antiplatelet therapy. We retrospectively compared patients receiving tirofiban during CAS versus those undergoing CAS without tirofiban, using propensity score matching. Ancillary antithrombotic therapy included in all patients aspirin, clopidogrel, and unfractioned heparin. The primary outcome was the change in serum troponin from baseline to postprocedural peak levels. A total of 30 patients undergoing CAS were included, 15 receiving tirofiban on top of heparin and dual oral antiplatelet therapy (DAPT) and 15 receiving only heparin and DAPT. Bail-out use of tirofiban was an exclusion criterion. RESULTS: Baseline troponin was 3.00 (0.06; 5.20) ng/mL in the tirofiban group vs. 4.6 (0.02; 13.10) ng/mL in the no-tirofiban group (P = 0.229), and postprocedural peak 3.5 (0.06; 5.50) ng/mL vs. 6.30 (0.09; 28.40) ng/mL (P = 0.191). Peak-baseline difference in troponin was lower in the tirofiban group than in the no-tirofiban group: 0.3 (0.00; 1.7) ng/mL vs. 1.3 (0.01; 10.00) ng/mL (P = 0.044); the relative peak-baseline change in troponin was analogously different: 24.3% (0%; 44.7%) vs. 50% (21.3%; 80.0%) (P = 0.039). No case of death, myocardial infarction, stroke, or transient ischemic attack occurred during in-hospital stay or at 1-month follow-up. CONCLUSIONS: Tirofiban during CAS might provide periprocedural myocardial protection and reduce myocardial injury as determined by serial troponin measurements.
Asunto(s)
Enfermedades de las Arterias Carótidas/terapia , Procedimientos Endovasculares/instrumentación , Cardiopatías/prevención & control , Inhibidores de Agregación Plaquetaria/uso terapéutico , Stents , Tirofibán/uso terapéutico , Troponina/sangre , Anciano , Anticoagulantes/uso terapéutico , Biomarcadores/sangre , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Bases de Datos Factuales , Terapia Antiplaquetaria Doble , Procedimientos Endovasculares/efectos adversos , Femenino , Cardiopatías/sangre , Cardiopatías/diagnóstico , Cardiopatías/etiología , Heparina/uso terapéutico , Humanos , Masculino , Inhibidores de Agregación Plaquetaria/efectos adversos , Puntaje de Propensión , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Tirofibán/efectos adversos , Resultado del TratamientoRESUMEN
Vertebrate organogenesis is critically sensitive to gene dosage and even subtle variations in the expression levels of key genes may result in a variety of tissue anomalies. MicroRNAs (miRNAs) are fundamental regulators of gene expression and their role in vertebrate tissue patterning is just beginning to be elucidated. To gain further insight into this issue, we analysed the transcriptomic consequences of manipulating the expression of miR-204 in the Medaka fish model system. We used RNA-Seq and an innovative bioinformatics approach, which combines conventional differential expression analysis with the behavior expected by miR-204 targets after its overexpression and knockdown. With this approach combined with a correlative analysis of the putative targets, we identified a wider set of miR-204 target genes belonging to different pathways. Together, these approaches confirmed that miR-204 has a key role in eye development and further highlighted its putative function in neural differentiation processes, including axon guidance as supported by in vivo functional studies. Together, our results demonstrate the advantage of integrating next-generation sequencing and bioinformatics approaches to investigate miRNA biology and provide new important information on the role of miRNAs in the control of axon guidance and more broadly in nervous system development.
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Axones/fisiología , Perfilación de la Expresión Génica , MicroARNs/metabolismo , Neurogénesis/genética , Oryzias/genética , Animales , Axones/ultraestructura , Biología Computacional , Técnicas de Silenciamiento del Gen , Secuenciación de Nucleótidos de Alto Rendimiento , Modelos Animales , Oryzias/embriología , Oryzias/metabolismo , Retina/embriología , Retina/metabolismo , Retina/ultraestructura , Análisis de Secuencia de ARNRESUMEN
During development, tissue-specific transcription factors regulate both protein-coding and non-coding genes to control differentiation. Recent studies have established a dual role for the transcription factor Pax6 as both an activator and repressor of gene expression in the eye, central nervous system, and pancreas. However, the molecular mechanism underlying the inhibitory activity of Pax6 is not fully understood. Here, we reveal that Trpm3 and the intronic microRNA gene miR-204 are co-regulated by Pax6 during eye development. miR-204 is probably the best known microRNA to function as a negative modulator of gene expression during eye development in vertebrates. Analysis of genes altered in mouse Pax6 mutants during lens development revealed significant over-representation of miR-204 targets among the genes up-regulated in the Pax6 mutant lens. A number of new targets of miR-204 were revealed, among them Sox11, a member of the SoxC family of pro-neuronal transcription factors, and an important regulator of eye development. Expression of Trpm/miR-204 and a few of its targets are also Pax6-dependent in medaka fish eyes. Collectively, this study identifies a novel evolutionarily conserved mechanism by which Pax6 controls the down-regulation of multiple genes through direct up-regulation of miR-204.
Asunto(s)
Evolución Molecular , Proteínas del Ojo , Ojo , Proteínas de Homeodominio , MicroARNs , Factores de Transcripción Paired Box , Proteínas Represoras , Animales , Sitios de Unión , Diferenciación Celular/genética , Cristalinas/genética , Cristalinas/metabolismo , Ojo/crecimiento & desarrollo , Ojo/metabolismo , Proteínas del Ojo/genética , Proteínas del Ojo/metabolismo , Regulación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Factor de Transcripción PAX6 , Factores de Transcripción Paired Box/genética , Factores de Transcripción Paired Box/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Factores de Transcripción SOXC/metabolismo , Canales Catiónicos TRPM/genética , Canales Catiónicos TRPM/metabolismo , Vertebrados/genética , Vertebrados/metabolismoRESUMEN
Vax2 is an eye-specific homeobox gene, the inactivation of which in mouse leads to alterations in the establishment of a proper dorsoventral eye axis during embryonic development. To dissect the molecular pathways in which Vax2 is involved, we performed a transcriptome analysis of Vax2(-/-) mice throughout the main stages of eye development. We found that some of the enzymes involved in retinoic acid (RA) metabolism in the eye show significant variations of their expression levels in mutant mice. In particular, we detected an expansion of the expression domains of the RA-catabolizing enzymes Cyp26a1 and Cyp26c1, and a downregulation of the RA-synthesizing enzyme Raldh3. These changes determine a significant expansion of the RA-free zone towards the ventral part of the eye. At postnatal stages of eye development, Vax2 inactivation led to alterations of the regional expression of the cone photoreceptor genes Opn1sw (S-Opsin) and Opn1mw (M-Opsin), which were significantly rescued after RA administration. We confirmed the above described alterations of gene expression in the Oryzias latipes (medaka fish) model system using both Vax2 gain- and loss-of-function assays. Finally, a detailed morphological and functional analysis of the adult retina in mutant mice revealed that Vax2 is necessary for intraretinal pathfinding of retinal ganglion cells in mammals. These data demonstrate for the first time that Vax2 is both necessary and sufficient for the control of intraretinal RA metabolism, which in turn contributes to the appropriate expression of cone opsins in the vertebrate eye.
Asunto(s)
Ojo/crecimiento & desarrollo , Ojo/metabolismo , Proteínas de Homeodominio/metabolismo , Opsinas/metabolismo , Tretinoina/metabolismo , Animales , Animales Modificados Genéticamente , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Familia 26 del Citocromo P450 , Femenino , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/genética , Hibridación in Situ , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , Opsinas/genética , Oryzias/genética , Oryzias/crecimiento & desarrollo , Oryzias/metabolismo , Embarazo , Células Fotorreceptoras Retinianas Conos/metabolismo , Ácido Retinoico 4-Hidroxilasa , Opsinas de Bastones/genética , Opsinas de Bastones/metabolismoRESUMEN
Cardiovascular disease remains decade after decade a leading cause of mortality, morbidity and resource use globally as well as locally. We have had the opportunity of being involved in several iterative breakthroughs in invasive cardiovascular procedures, ranging from the advent of coronary stents to transcatheter mitral valve repair. Building up such extensive clinical and research experience, we hereby present 25 years of cardiovascular interventions at Pineta Grande Hospital and Casa di Salute S. Lucia, respectively in Castel Volturno, and S. Giuseppe Vesuviano, both in the Italian Campania region, where the same team of interventional cardiologists has managed to adopt and master several cardiovascular innovations for the benefit of thousands of patients. Our experience showcases the evolution of invasive cardiology, especially in diagnostic and therapeutic practices. Key highlights include advancements in coronary procedures, with the introduction of bare-metal stents, drug-eluting stents and drug-coated balloons, despite the setback of bioresorbable vascular scaffolds, as well as transcatheter aortic valve implantation and innovative approaches to mitral regurgitation. Furthermore, this overview scrutinizes procedural challenges, patient outcomes, and quality of life improvements, providing a rich tapestry of clinical experiences and research insights. It serves as a testament to the dynamic nature of interventional cardiology, offering a forward-looking perspective on future trends and technologies. We hope that this overview will prove an informative and insightful read for those seeking to understand the intricate journey of invasive cardiovascular care over the past decades and its trajectory into the future.
RESUMEN
MicroRNAs (miRNAs) are small noncoding RNAs that have important roles in the regulation of gene expression. The roles of individual miRNAs in controlling vertebrate eye development remain, however, largely unexplored. Here, we show that a single miRNA, miR-204, regulates multiple aspects of eye development in the medaka fish (Oryzias latipes). Morpholino-mediated ablation of miR-204 expression resulted in an eye phenotype characterized by microphthalmia, abnormal lens formation, and altered dorsoventral (D-V) patterning of the retina, which is associated with optic fissure coloboma. Using a variety of in vivo and in vitro approaches, we identified the transcription factor Meis2 as one of the main targets of miR-204 function. We show that, together with altered regulation of the Pax6 pathway, the abnormally elevated levels of Meis2 resulting from miR-204 inactivation are largely responsible for the observed phenotype. These data provide an example of how a specific miRNA can regulate multiple events in eye formation; at the same time, they uncover an as yet unreported function of Meis2 in the specification of D-V patterning of the retina.
Asunto(s)
Proteínas de Peces/genética , Cristalino/metabolismo , MicroARNs/genética , Retina/metabolismo , Factores de Transcripción/genética , Animales , Línea Celular , Embrión no Mamífero/embriología , Embrión no Mamífero/metabolismo , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/genética , Humanos , Hibridación in Situ , Cristalino/embriología , Modelos Genéticos , Organogénesis/genética , Oryzias/embriología , Oryzias/genética , Retina/embriología , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
AIMS: Transcatheter aortic valve implantation has become an established treatment for severe aortic stenosis, thanks to key improvements achieved by new-generation devices. Their comparative effectiveness and safety are, however, still uncertain. METHODS: We queried a prospective registry on transcatheter aortic valve implantation to compare Evolut and Portico devices, focusing on procedural, in-hospital, and mid-term outcomes. Unadjusted and propensity-adjusted analyses were carried out. RESULTS: In all, 233 patients were included, 119 (51.1%) receiving Evolut and 114 (48.9%) Portico. Several differences in baseline and procedural features were evident, including comorbidities, device size, and postdilation (all Pâ<â0.05). Unadjusted analysis for procedural results showed significant differences in fluoroscopy time, left ventricular ejection fraction, and aortic regurgitation (all Pâ<â0.05), whereas device and procedural success rates were not significantly different (both Pâ>â0.05). In-hospital outcomes were not significantly different (all Pâ>â0.05). Survival analysis for mid-term follow-up (6â±â7 months) outcomes showed no significant differences in death, stroke, myocardial infarction, major vascular complication, or major bleeding (all Pâ>â0.05). Conversely, Evolut appeared associated with lower peak and mean aortic gradients (both Pâ<â0.05), but higher rate of permanent pacemaker implantation (Pâ=â0.043). Propensity-score-adjusted analysis largely confirmed the similar performance of the two devices, including peak and mean aortic gradients (both Pâ>â0.05). However, Evolut continued to be associated even at adjusted analysis with an increased risk of pacemaker implantation (Pâ=â0.018). CONCLUSION: The acute and mid-term comparative safety and effectiveness of Evolut and Portico in experienced hands are similar, with the notable exception of a lower risk of permanent pacemaker implantation with Portico.
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Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Prótesis Valvulares Cardíacas , Diseño de Prótesis , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Anciano , Anciano de 80 o más Años , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/fisiopatología , Investigación sobre la Eficacia Comparativa , Femenino , Hemodinámica , Humanos , Italia , Masculino , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/terapia , Recuperación de la Función , Sistema de Registros , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del TratamientoRESUMEN
Several devices are available for infrainguinal endovascular therapy, with drug-eluting stents (DES) among the most promising. Bioresorbable vascular scaffolds (BVS) may further improve outcomes. We have liberally used in our practice coronary DES and BVS for infrainguinal endovascular therapy and hereby report our preliminary results. We conducted an observational study by retrospectively identifying characteristics of patients undergoing infrainguinal implantation of coronary DES or BVS. We compared the risk of major adverse events (MAE: death, amputation, or target vessel revascularization [TVR]) and components of MAE in the overall sample and after propensity matching. We included a total of 204 patients (207 limbs), 148 (72.5%) treated with DES and 56 (27.5%) with BVS. Bivariate analysis showed that TVR was less common in the DES group (41.9% vs 18.4%, P = .014). However, propensity-matched analysis showed nearly identical risks of MAE, amputation, TVR, or symptom burden with DES and BVS (all P > .05). In conclusion, the present pilot experience with coronary BVS suggests that they could provide acceptable results for infrainguinal endovascular procedures, comparable to those obtained by their metallic counterpart.
Asunto(s)
Implantes Absorbibles , Enfermedad de la Arteria Coronaria/terapia , Stents Liberadores de Fármacos , Sirolimus/uso terapéutico , Implantes Absorbibles/efectos adversos , Anciano , Enfermedad de la Arteria Coronaria/diagnóstico , Vasos Coronarios/efectos de los fármacos , Stents Liberadores de Fármacos/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea/métodos , Estudios Retrospectivos , Factores de Riesgo , Resultado del TratamientoRESUMEN
BACKGROUND: Several strategies have been envisioned to reduce the risk of contrast-induced nephropathy, but the most modifiable approach for a treating physician is to minimize contrast administration. To date, there is no report on the use of Osprey Medical's new-generation DyeVert Plus system in coronary or peripheral applications. We aimed to appraise the role of the DyeVert Plus system inclusive of contrast reduction and real-time monitoring in a consecutive series of patients undergoing coronary or peripheral invasive procedures. METHODS: Baseline, procedural, and outcome details for patients undergoing coronary or peripheral invasive procedures were collected from our institutional database. We primarily focused on total and relative amount of contrast saved, as calculated and displayed by the DyeVert Plus system. RESULTS: The DyeVert Plus system was used in 10 patients. All procedures were successfully completed with adequate and high-quality angioscopic and angiographic images. No adverse events occurred up to discharge in any patients, with the notable exception of 1 case of asymptomatic and uneventful contrast-induced nephropathy. Average contrast volume was 79.9 ± 48.8 mL (95% confidence interval [CI], 53.2 to 109.4), thanks to an absolute saving of 55.8 ± 31.9 mL (95% CI, 39.1 to 76.7; P<.05) and a relative saving of 41.8 ± 7.3% (95% CI, 37.5 to 46.4; P<.05). Comparison of contrast volume estimates between DyeVert Plus vs manual measurements showed a minimal difference of 1.6 ± 1.9 mL (95% CI, 2.9 to 0.5; P<.05). CONCLUSION: Use of the new-generation DyeVert Plus system inclusive of contrast reduction and real-time monitoring is feasible in both coronary and peripheral applications while significantly reducing contrast volume.
Asunto(s)
Angiografía , Medios de Contraste , Enfermedad de la Arteria Coronaria/diagnóstico , Sistemas de Liberación de Medicamentos/métodos , Monitoreo de Drogas , Enfermedades Renales , Enfermedades Vasculares Periféricas/diagnóstico , Anciano , Angiografía/efectos adversos , Angiografía/métodos , Vasos Sanguíneos/diagnóstico por imagen , Medios de Contraste/administración & dosificación , Medios de Contraste/efectos adversos , Relación Dosis-Respuesta a Droga , Cálculo de Dosificación de Drogas , Monitoreo de Drogas/instrumentación , Monitoreo de Drogas/métodos , Femenino , Humanos , Italia , Enfermedades Renales/inducido químicamente , Enfermedades Renales/diagnóstico , Enfermedades Renales/prevención & control , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
BACKGROUND: Drug-eluting stents (DES) are now considered the most promising device to treat peripheral artery disease (PAD) and minimize restenosis. There is uncertainty however on the best antirestenotic drug for such devices. In particular, biolimus (i.e. umirolimus) and everolimus are two of the most promising agents, given the extensive data in support of their coronary safety and efficacy, but their comparative effectiveness for peripheral interventions is not established. METHODS: Building upon our extensive experience in the percutaneous treatment of infra-inguinal artery disease with DES, we compared the acute and longterm outlook of patients treated with biolimus-eluting stents (BES) and everolimus-eluting stents (EES). We collected baseline, procedural and outcome details on all patients undergoing infra-inguinal BES or EES implantation. The endpoints of interest were death, amputation, revascularization, their composite, and change in Fontaine class. A total of 80 patients were included (20 treated with BES and 60 with EES). Most features were similar in the two groups, despite longer lesions in the EES group. Unadjusted analysis showed similar results irrespective of the drug used, with composite endpoint occurring, respectively, in 4 (20.0%) and 10 (16.7%) (p=0.741). RESULTS AND CONCLUSION: However, analysis with inverse probability of treatment weighting showed significant differences in the risk of revascularization (hazard ratio of BES vs EES=9.55 [95% confidence interval 2.16-42.23], p=0.003) and composite endpoint (hazard ratio=5.11 [1.33-19.62], p=0.018). In conclusion, EES appear superior to BES for endovascular therapy of infrainguinal artery disease. Dedicated randomized trials are required to definitely confirm or disprove these findings.
Asunto(s)
Fármacos Cardiovasculares/administración & dosificación , Stents Liberadores de Fármacos , Procedimientos Endovasculares/instrumentación , Everolimus/administración & dosificación , Enfermedad Arterial Periférica/terapia , Sirolimus/análogos & derivados , Anciano , Anciano de 80 o más Años , Amputación Quirúrgica , Fármacos Cardiovasculares/efectos adversos , Investigación sobre la Eficacia Comparativa , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/mortalidad , Everolimus/efectos adversos , Femenino , Humanos , Recuperación del Miembro , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/diagnóstico por imagen , Enfermedad Arterial Periférica/mortalidad , Diseño de Prótesis , Estudios Retrospectivos , Sirolimus/administración & dosificación , Sirolimus/efectos adversos , Factores de Tiempo , Resultado del TratamientoRESUMEN
Tirofiban is used in the treatment of patients with acute coronary syndrome submitted to percutaneous coronary intervention (PCI). We have, previously, shown that tirofiban stimulates VEGF expression and promotes proliferation of endothelial cells. VEGF is a well known inhibitor of endothelial cell apoptosis. TNF-α is a pro-apoptotic cytokine released in the site of a vascular injury, including balloon angioplasty. We thought to investigate whether tirofiban was able to protect endothelial cells from cell death induced by TNF-α. For this study, we used human umbilical vein endothelial cells (HUVEC). Analysis of apoptosis was performed by propidium iodide incorporation, annexin V staining and measure of active caspase 3 levels. Western blot served for a semiquantitative measure of Akt activation, VEGF, and the pro-apoptotic Bim and Bak. Our results show that TNF-α was unable to activate caspase 3 and produce cell death in the presence of tirofiban. Activation of apoptosis was preceded by upregulation of Bim and Bak that resulted decreased after addition of tirofiban. The anti-apoptosis effect of tirofiban was reproduced by VEGF and counteracted by VEGFR2 blockade and the cation chelating agent ethylene glycol tetraacetic acid (EGTA). The use of p-Akt inhibitor, BEZ235,and Akt knockdown, suggested that pAkt mediated the prosurvival effect of tirofiban. In conclusion, tirofiban protects endothelial cells from apoptosis stimulated by TNF-α, due to its ability to stimulate VEGF production.
Asunto(s)
Apoptosis/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Tirosina/análogos & derivados , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Western Blotting , Técnicas de Cultivo de Célula , Supervivencia Celular/efectos de los fármacos , Células Endoteliales/metabolismo , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Integrina beta3/biosíntesis , Tirofibán , Factor de Necrosis Tumoral alfa/farmacología , Tirosina/farmacología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidoresRESUMEN
Inhibition of nuclear factor (NF)-kappaB/Rel can sensitise many tumour cells to death-inducing stimuli, including chemotherapeutic agents, and there are data suggesting that disruption of NF-kappaB may be of therapeutic interest in melanoma. We found that rapamycin sensitised a human melanoma cell line, established from a patient, to the cytolytic effects of doxorubicin. Doxorubicin is a striking NF-kappaB/Rel-inducer, we therefore investigated if rapamycin interfered with the pathway of NF-kappaB/Rel activation, i.e. IkappaBalpha-phosphorylation, -degradation and NF-kappaB/Rel nuclear translocation, and found that the macrolide agent caused a block of IKK kinase activity that was responsible for a reduced nuclear translocation of transcription factors. Western blots for Bcl-2 and c-IAP1 showed increased levels of these anti-apoptotic proteins in cells incubated with doxorubicin, in accordance with NF-kappaB/Rel activation, while rapamycin clearly downmodulated these proteins, in line with its pro-apoptotic ability. The effect of the macrolide on NF-kappa B/Rel induction appeared to be independent of the block in the PI3k/Akt pathway, because it could not be reproduced by the phosphatidyl inositol 3 kinase (PI3k) inhibitor, wortmannin. Recently, the immunophilin, FKBP51, has been shown to be essential for the function of IKK kinase. We found high expression levels of FKBP51 in melanoma cells. Moreover, we confirmed the involvement of this immunophilin in the control of IKK activity. Indeed, IkappaBalpha could not be degraded when FKBP51 was downmodulated by short-interfering RNAs (siRNAs). These findings provide a possible mechanism for the downmodulation of NF-kappaB by rapamycin, since the macrolide agent specifically inhibits FKBP51 isomerase activity. In conclusion, our study demonstrates that rapamycin blocked NF-kappaB/Rel activation independently of PI3k/Akt inhibition suggesting that the macrolide agent could synergise with NF-kappaB-inducing anti-cancer drugs in PTEN-positive tumours.
Asunto(s)
Antibióticos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Doxorrubicina/farmacología , Melanoma/patología , FN-kappa B/antagonistas & inhibidores , Sirolimus/farmacología , Androstadienos/farmacología , Western Blotting , Línea Celular Tumoral , Humanos , Proteínas Inhibidoras de la Apoptosis , Melanoma/tratamiento farmacológico , FN-kappa B/efectos de los fármacos , Proteínas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , ARN Neoplásico/análisis , Factor de Transcripción ReIA , Transfección , Ubiquitina-Proteína Ligasas , WortmaninaRESUMEN
Loss of cell adhesion and enhancement of cell motility contribute to epithelial-to-mesenchymal transition during development. These processes are related to a) rearrangement of cell-cell and cell-substrate adhesion molecules; b) cross talk between extra-cellular matrix and internal cytoskeleton through focal adhesion molecules. Focal adhesions are stringently regulated transient structures implicated in cell adhesion, spreading and motility during tissue development. Importantly, despite the extensive elucidation of the molecular composition of focal adhesions, the complex regulation of their dynamics is largely unclear. Here, we demonstrate, using live-imaging in medaka, that the microRNA miR-204 promotes both mesenchymal neural crest and lens cell migration and elongation. Overexpression of miR-204 results in upregulated cell motility, while morpholino-mediated ablation of miR-204 activity causes abnormal lens morphogenesis and neural crest cell mislocalization. Using a variety of in vivo and in vitro approaches, we demonstrate that these actions are mediated by the direct targeting of the Ankrd13A gene, which in turn controls focal cell adhesion formation and distribution. Significantly, in vivo restoration of abnormally elevated levels of Ankrd13A resulting from miR-204 inactivation rescued the aberrant lens phenotype in medaka fish. These data uncover, for the first time in vivo, the role of a microRNA in developmental control of mesenchymal cell migration and highlight miR-204 as a "master regulator" of the molecular networks that regulate lens morphogenesis in vertebrates.
Asunto(s)
Movimiento Celular , Cristalino/citología , Proteínas de la Membrana/metabolismo , Mesodermo/citología , MicroARNs/metabolismo , Cresta Neural/citología , Oryzias/metabolismo , Animales , Secuencia de Bases , Línea Celular , Movimiento Celular/efectos de los fármacos , Citoesqueleto/efectos de los fármacos , Citoesqueleto/metabolismo , Adhesiones Focales/efectos de los fármacos , Adhesiones Focales/metabolismo , Humanos , Cristalino/efectos de los fármacos , Cristalino/metabolismo , Modelos Biológicos , Datos de Secuencia Molecular , Morfolinos/farmacología , Cresta Neural/metabolismo , FenotipoRESUMEN
MicroRNAs (miRNAs) are small noncoding RNAs that control gene expression by inducing RNA cleavage or translational inhibition. Most human miRNAs are intragenic and are transcribed as part of their hosting transcription units. We hypothesized that the expression profiles of miRNA host genes and of their targets are inversely correlated and devised a novel procedure, HOCTAR (host gene oppositely correlated targets), which ranks predicted miRNA target genes based on their anti-correlated expression behavior relative to their respective miRNA host genes. HOCTAR is the first tool for systematic miRNA target prediction that utilizes the same set of microarray experiments to monitor the expression of both miRNAs (through their host genes) and candidate targets. We applied the procedure to 178 human intragenic miRNAs and found that it performs better than currently available prediction softwares in pinpointing previously validated miRNA targets. The high-scoring HOCTAR predicted targets were enriched in Gene Ontology categories, which were consistent with previously published data, as in the case of miR-106b and miR-93. By means of overexpression and loss-of-function assays, we also demonstrated that HOCTAR is efficient in predicting novel miRNA targets and we identified, by microarray and qRT-PCR procedures, 34 and 28 novel targets for miR-26b and miR-98, respectively. Overall, we believe that the use of HOCTAR significantly reduces the number of candidate miRNA targets to be tested compared to the procedures based solely on target sequence recognition. Finally, our data further confirm that miRNAs have a significant impact on the mRNA levels of most of their targets.
Asunto(s)
Perfilación de la Expresión Génica , Regulación de la Expresión Génica/fisiología , MicroARNs/genética , MicroARNs/fisiología , Análisis de Secuencia por Matrices de Oligonucleótidos , Algoritmos , Predicción/métodos , Perfilación de la Expresión Génica/métodos , Genes , Células HeLa , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Análisis de Secuencia de ARN/métodosRESUMEN
Several lines of evidence support the view that rapamycin inhibits NF-kappaB. TNF-alpha, a potent inducer of NF-kappaB, is released after artery injury (e.g., balloon angioplasty) and plays an important role in inflammation and restenosis. We investigated the effect of rapamycin on NF-kappaB activation and apoptosis in vascular smooth muscle cells (VSMCs) stimulated with TNF-alpha. Using EMSA, we found that TNF-alpha caused NF-kappaB nuclear translocation in VSMCs after 1 h of incubation. Rapamycin inhibited IkappaBalpha degradation, thereby preventing nuclear translocation. Activation of NF-kappaB was accompanied by an increase of Bcl-xL and Bfl-1/A1 proteins, detected by Western blot assay, whereas rapamycin prevented the TNF-alpha-induced enhancement of these antiapoptotic proteins. The extent of apoptosis of VSMCs exposed to TNF-alpha was significantly enhanced by rapamycin. The effect of rapamycin appeared to be independent of the phosphatidylinositol 3-kinase/Akt-protein kinase B survival pathway, because the phosphatidylinositol 3-kinase inhibitor wortmannin neither prevented IkappaBalpha degradation nor increased apoptosis of cells incubated with TNF-alpha. Finally, we demonstrate that the large immunophilin FK-506 binding protein FKBP51 is essential for TNF-alpha-induced NF-kappaB activation in VSMCs. Our findings show that rapamycin inhibits NF-kappaB activation and acts in concert with TNF-alpha in induction of VSMC apoptosis.
Asunto(s)
Antibacterianos/farmacología , Apoptosis/efectos de los fármacos , Músculo Liso Vascular/metabolismo , FN-kappa B/efectos de los fármacos , Sirolimus/farmacología , Translocación Genética/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Animales , Western Blotting , Células Cultivadas , Ensayo de Cambio de Movilidad Electroforética , Quinasa I-kappa B/metabolismo , Inmunosupresores/metabolismo , Masculino , Músculo Liso Vascular/citología , Proteína Oncogénica p65(gag-jun)/genética , ARN Interferente Pequeño/uso terapéutico , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacos , Tacrolimus/metabolismo , Proteínas de Unión a Tacrolimus/metabolismo , Transfección , Proteína bcl-X/genéticaRESUMEN
The phosphatidyl-inositol 3 kinase (PI3k)/Akt pathway has been implicated in childhood acute lymphoblastic leukemia (ALL). Because rapamycin suppresses the oncogenic processes sustained by PI3k/Akt, we investigated whether rapamycin affects blast survival. We found that rapamycin induces apoptosis of blasts in 56% of the bone marrow samples analyzed. Using the PI3k inhibitor wortmannin, we show that the PI3k/Akt pathway is involved in blast survival. Moreover, rapamycin increased doxorubicin-induced apoptosis even in nonresponder samples. Anthracyclines activate nuclear factor kappaB (NF-kappaB), and disruption of this signaling pathway increases the efficacy of apoptogenic stimuli. Rapamycin inhibited doxorubicin-induced NF-kappaB in ALL samples. Using a short interfering (si) RNA approach, we demonstrate that FKBP51, a large immunophilin inhibited by rapamycin, is essential for drug-induced NF-kappaB activation in human leukemia. Furthermore, rapamycin did not increase doxorubicin-induced apoptosis when NF-kappaB was overexpressed. In conclusion, rapamycin targets 2 pathways that are crucial for cell survival and chemoresistance of malignant lymphoblasts--PI3k/Akt through the mammalian target of rapamycin and NF-kappaB through FKBP51--suggesting that the drug could be beneficial in the treatment of childhood ALL.