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The infratemporal fossa and pterygopalatine fossa are critical pathways for blood vessels and nerves leading to the orbit, nasal cavity, and oral cavity. Anatomical observation of these areas is challenging for learners due to their complex connections with surrounding structures and their deep location within the body. Since it is not easy to understand this area in three dimensions with only textbook images, there is a need to produce three-dimensional (3D) content. Most existing 3D data have reconstructed the digital imaging and communication in medicine files from computed tomography images with high accuracy; however, the surrounding structures often obstruct the view. For this reason, this project utilized Cinema4D (R18; Maxon) software to refine the modeled bones and to create 3D models of muscles, blood vessels, and nerves that accurately represent their anatomical shapes and pathways. To facilitate easier access for learners via PC, the content was converted into PDF format. This enables the educational materials to be more easily viewed and the main structures more clearly observed using a computer-based viewer.
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Large gulls are generalist predators that play an important role in Arctic food webs. Describing the migratory patterns and phenology of these predators is essential to understanding how Arctic ecosystems function. However, from all six large Arctic gull taxa, including three long-distance migrants, to date seasonal movements have been studied only in three and with small sample sizes. To document the flyways and migratory behaviour of the Vega gull, a widespread but little-studied Siberian migrant, we monitored 28 individuals with GPS loggers over a mean period of 383 days. Birds used similar routes in spring and autumn, preferring coastal to inland or offshore routes, and travelled 4000-5500 km between their breeding (Siberia) and wintering grounds (mainly the Republic of Korea and Japan). Spring migration mainly occurred in May, and was twice as fast and more synchronized among individuals than autumn migration. Migration bouts mainly occurred during the day and twilight, but rates of travel were always higher during the few night flights. Flight altitudes were nearly always higher during migration bouts than during other bouts, and lower during twilight than during night or day. Altitudes above 2000m were recorded during migrations, when birds made non-stop inland flights over mountain ranges and vast stretches of the boreal forest. Individuals showed high inter-annual consistency in their movements in winter and summer, indicating strong site fidelity to their breeding and wintering sites. Within-individual variation was similar in spring and autumn, but between individual variation was higher in autumn than in spring. Compared to previous studies, our results suggest that the timing of spring migration in large Arctic gulls is likely constrained by snowmelt at breeding grounds, while the duration of migration windows could be related to the proportion of inland versus coastal habitats found along their flyways ('fly-and-forage' strategy). Ongoing environmental changes are hence likely in short term to alter the timing of their migration, and in long term possibly affect the duration if e.g. the resource availability along the route changes in the future.
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Charadriiformes , Animales , Ecosistema , Migración Animal , Aves , Estaciones del AñoRESUMEN
Macrophage inhibitory cytokine-1 (MIC-1) has been reported to be elevated in various human cancers including melanoma; however, the function of MIC-1 in cancer remains unclear. In this study, we attempt to clarify the role of MIC-1 in tumor pathogenesis by employing the orthotopic B16F1 melanoma mouse model in which serum MIC-1 levels are positively correlated with tumor size. By stably transfecting a MIC-1 expression construct into B16F1 melanoma cells, we increased the expression and secretion levels of MIC-1. This increase in MIC-1 expression significantly enhanced the growth of tumors derived from B16F1 cells in vivo, despite not affecting in vitro cell growth. The elevated MIC-1 expression in B16F1 cells also resulted in lymph node metastasis in B16F1 tumor-bearing mice, significantly increasing mortality. Interestingly, among small melanoma tumors of similar size, tumors derived from the MIC-1-transfected B16F1 cells exhibited enhanced blood vessel formation compared with those of mock transfectant cells. Also, more MIC-1 was found in well-vascularized tumor regions than in poorly vascularized tumor regions. Moreover, conditioned medium (CM) of the MIC-1-transfected melanoma cells enhanced the angiogenic properties of endothelial cells more than CM of mock transfectant cells. Notably, hypoxic culture conditions forced parental B16F1 cells to secrete more endothelial cell-stimulating factors, among which the function of MIC-1 was confirmed by blocking the effects with an anti-MIC-1 antibody. Taken together, these results suggest that the MIC-1 produced by melanoma cells in response to oxygen deprivation promotes tumor vascularization during melanoma development in vivo, leading to enhanced tumor growth and metastasis.
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Factor 15 de Diferenciación de Crecimiento/metabolismo , Melanoma/genética , Neoplasias Cutáneas/genética , Animales , Línea Celular Tumoral , Proliferación Celular , Femenino , Humanos , Melanoma/patología , Ratones , Metástasis de la Neoplasia , Neovascularización Patológica , Neoplasias Cutáneas/patología , TransfecciónRESUMEN
PURPOSE: Common celiomesenteric trunk (CMT) is a rare anatomical variation that occurs in 0.5% to 3.4% of the general population. Its presence may complicate planning and implantation of fenestrated and branched stent-grafts because the wide diameter and short length of the CMT to its bifurcation does not allow sufficient sealing for placement of bridging stents. CASE REPORT: We report a patient with thoracoabdominal aortic aneurysm (TAAA) and CMT treated by fenestrated-branched endovascular aortic repair (FB-EVAR) using double kissing directional branches to incorporate the celiac axis and superior mesenteric artery. Pitfalls of stent design and implantation are outlined. CONCLUSION: Double kissing directional branches should be considered as an alternative to incorporate vessels with early bifurcation such as a CMT.
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Aneurisma de la Aorta Torácica , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/cirugía , Prótesis Vascular , Procedimientos Endovasculares/efectos adversos , Humanos , Diseño de Prótesis , Factores de Riesgo , Stents , Factores de Tiempo , Resultado del TratamientoRESUMEN
Macrophage inhibitory cytokine-1 (MIC-1) is a cytokine with pleotropic actions and its expression is markedly increased by inflammation and cardiac injury and in cancers. In particular, MIC-1 production after cardiac ischemia injury is associated with enhanced cardiac angiogenesis as well as myocardial protection. However, it remains uncertain whether MIC-1 itself has proangiogenic activity. In this study, we tried to determine the precise role of MIC-1 in physiological and pathological angiogenesis. Human microvessel endothelial cells responded to MIC-1 with enhanced angiogenic behaviors. Employing various angiogenesis assays, MIC-1 was found to promote vessel formation and development with a potency similar to that of vascular endothelial growth factor (VEGF). MIC-1 transgenic (Tg) mice also displayed enhanced neovascularization in both developing embryos and neonatal mouse retinas, compared with wild-type mice. Furthermore, endothelial cells (ECs) isolated from MIC-1 Tg mouse lung exhibited higher angiogenic potential than ECs from wild-type lung. MIC-1-induced angiogenesis was also observed in the recovery or healing processes of injuries such as hindlimb ischemia and skin wounds in mice. However, unlike VEGF, MIC-1 induced neither endothelial inflammation nor increased vascular permeability. In ECs, the MIC-1 signal exerted proangiogenic actions via the MEK/extracellular signal-regulated kinase- and phosphatidylinositol 3-kinase/Akt-dependent pathways. Notably, these MIC-1 signaling events in ECs were abrogated by small interfering RNA-mediated knockdown of GFRAL, suggesting that GFRAL is an EC receptor for MIC-1. In summary, we here show a novel role of MIC-1 as a potent EC activator, which promotes both normal and injury-related angiogenesis.
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Receptores del Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Factor 15 de Diferenciación de Crecimiento/metabolismo , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Neovascularización Fisiológica , Transducción de Señal , Animales , Embrión de Mamíferos/metabolismo , Miembro Posterior/irrigación sanguínea , Miembro Posterior/patología , Humanos , Inflamación/patología , Isquemia/patología , Sistema de Señalización de MAP Quinasas , Ratones Endogámicos C57BL , Ratones Transgénicos , Microvasos/citología , Permeabilidad , Fosfatidilinositol 3-Quinasa/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Regeneración/fisiología , Retina/metabolismo , Piel/patología , Cicatrización de HeridasRESUMEN
The epidermal growth factor receptor (EGFR), a member of ErbB receptor tyrosine kinase (RTK) family, is activated through growth factor-induced reorganization of the actin cytoskeleton and subsequent dimerization. We herein explored the molecular mechanism underlying the suppression of ligand-induced EGFR dimerization by CD99 agonists and its relevance to tumor growth in vivo. Epidermal growth factor (EGF) activated the formation of c-Src/focal adhesion kinase (FAK)-mediated intracellular complex and subsequently induced RhoA-and Rac1-mediated actin remodeling, resulting in EGFR dimerization and endocytosis. In contrast, CD99 agonist facilitated FAK dephosphorylation through the HRAS/ERK/PTPN12 signaling pathway, leading to inhibition of actin cytoskeletal reorganization via inactivation of the RhoA and Rac1 signaling pathways. Moreover, CD99 agonist significantly suppressed tumor growth in a BALB/c mouse model injected with MDA-MB-231 human breast cancer cells. Taken together, these results indicate that CD99-derived agonist ligand inhibits epidermal growth factor (EGF)-induced EGFR dimerization through impairment of cytoskeletal reorganization by PTPN12-dependent c-Src/FAK inactivation, thereby suppressing breast cancer growth.
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INTRODUCTION: High flow rates may develop in arteriovenous fistula (AVF), resulting in clinical syndromes of steal, aneurysmal fistula, or high-output cardiac failure. Various techniques with varying success have been advocated to treat this difficult problem. We present a hemodynamically validated novel banding technique. METHODS: We designed a computational fluid dynamic (CFD) model of the native high-flow AVF and tested various juxta-anastomotic venous diameters to determine the effect on AVF blood flow and pressure. We translated this principle in our banding technique, wherein adjustable banding was performed in conjunction with ultrasound-guided brachial artery flow measurement to determine the optimal band diameter. Polyurethane patch was used to fashion the adjustable band. Patient demographics, AVF flow parameters pre- and postintervention, operative intervention, and ultrasound follow-up data were collected prospectively. RESULTS: Our CFD testing demonstrated that the band diameter needed to achieve optimal distal blood pressure and preserve AVF flow depending on blood pressure, end capillary pressure, venous pressure, and vascular diameters. Five patients subsequently underwent dynamic banding of symptomatic high-flow AVF. Mean brachial artery blood flow rates pre- and postbanding were 2964 mL/min (confidence interval [CI]: 1487-4440 mL/min) and 1099 mL/min (CI: 571.7-1627 mL/min), respectively (P = .01). All patients had symptomatic improvement, and at a mean follow-up of 1 year, this benefit was sustained with no AVF thrombosis or loss. CONCLUSION: Adjustable dynamic band using ultrasound-guided brachial artery flow shows promising results in producing accurate AVF blood flow reduction with sustained efficacy in the short term for patients with symptomatic high-flow AVF.
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Derivación Arteriovenosa Quirúrgica/efectos adversos , Arteria Braquial/fisiopatología , Hemodinámica , Complicaciones Posoperatorias/cirugía , Diálisis Renal , Adolescente , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo , Arteria Braquial/diagnóstico por imagen , Simulación por Computador , Humanos , Ligadura , Persona de Mediana Edad , Modelos Cardiovasculares , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/fisiopatología , Estudios Prospectivos , Flujo Sanguíneo Regional , Reoperación , Factores de Tiempo , Resultado del Tratamiento , Ultrasonografía IntervencionalRESUMEN
The tetrapeptide Arg-Leu-Tyr-Glu (RLYE), a vascular endothelial growth factor (VEGF) receptor-2 antagonist, has been used previously either alone or in combination with chemotherapeutic drugs for treating colorectal cancer in a mouse model. We analyzed the half-life of the peptide and found that because of degradation by aminopeptidases B and N, it had a short half-life of 1.2 hours in the serum. Therefore, to increase the stability and potency of the peptide, we designed the modified peptide, N-terminally acetylated RLYE (Ac-RLYE), which had a strongly stabilized half-life of 8.8 hours in serum compared with the original parent peptide. The IC50 value of Ac-RLYE for VEGF-A-induced endothelial cell migration decreased to approximately 37.1 pM from 89.1 pM for the parent peptide. Using a mouse xenograft tumor model, we demonstrated that Ac-RLYE was more potent than RLYE in inhibiting tumor angiogenesis and growth, improving vascular integrity and normalization through enhanced endothelial cell junctions and pericyte coverage of the tumor vasculature, and impeding the infiltration of macrophages into tumor and their polarization to the M2 phenotype. Furthermore, combined treatment of Ac-RLYE and irinotecan exhibited synergistic effects on M1-like macrophage activation and apoptosis and growth inhibition of tumor cells. These findings provide evidence that the N-terminal acetylation augments the therapeutic effect of RLYE in solid tumors via inhibition of tumor angiogenesis, improvement of tumor vessel integrity and normalization, and enhancement of the livery and efficacy of the coadministered chemotherapeutic drugs. SIGNIFICANCE STATEMENT: The results of this study demonstrate that the N-terminal acetylation of the tetrapeptide RLYE (Ac-RLYE), a novel vascular endothelial growth factor receptor-2 (VEGFR-2) inhibitor, significantly improves its serum stability, antiangiogenic activity, and vascular normalizing potency, resulting in enhanced therapeutic effect on solid tumors. Furthermore, the combined treatment of Ac-RLYE with the chemotherapeutic drug, irinotecan, synergistically enhanced its antitumor efficacy by improving the perfusion and delivery of the drug into the tumors and stimulating the conversion of the tumor-associated macrophages to an immunostimulatory M1-like antitumor phenotype.
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Antineoplásicos/administración & dosificación , Neovascularización Patológica/sangre , Neovascularización Patológica/tratamiento farmacológico , Oligopéptidos/administración & dosificación , Péptido Hidrolasas/sangre , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Células HCT116 , Células Endoteliales de la Vena Umbilical Humana , Humanos , Masculino , Ratones , Ratones Desnudos , Estabilidad Proteica/efectos de los fármacos , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto/métodosRESUMEN
BACKGROUND: The epithelial-to-mesenchymal transition (EMT) is closely associated with cancer invasion and metastasis. Since the transforming growth factor ß (TGF-ß) and Wnt signals induce EMT in various epithelial cell types, we examined whether and how the CD82/KAI1 metastasis suppressor affects the TGF-ß and Wnt signal-dependent EMT in human prostate cancer cells. METHODS: The invasiveness of cancer cells was evaluated by examining their ability to pass through the basement membrane matrigel. The subcellular localizations of Smad4 and ß-catenin proteins were respectively examined by confocal microscopy following immunofluorescence antibody staining and immunoblotting analysis following subcellular fractionation. The transcriptional activities of the TGF-ß1 -responsive TRE and Wnt-responsive Tcf/Lef promoters were determined by a luciferase reporter assay following transfection of the recombinant reporter vector into the cell. RESULTS: TGF-ß1 and Wnt3a treatments of human prostate cancer cells without CD82 expression resulted in not only increased invasiveness but also EMT involving the development of motile structures, downregulation of E-cadherin, and upregulation of the mesenchymal proteins. However, in the cells with high levels of CD82, the TGF-ß1 and Wnt3a stimulations neither elevated invasiveness nor induced EMT. Furthermore, the TGF-ß1 signaling events occurring in the CD82-deficient cells, such as phosphorylation of Smad2, nuclear translocation of Smad4, and transactivation of the TRE promoter, did not take place in the high CD82-expressing cells. Further, high CD82 expression interfered with the Wnt signal-dependent alterations in the phosphorylation pattern of glycogen synthase kinase 3ß (GSK-3ß) in prostate cancer cells, which allowed GSK-3ß to continue phosphorylating ß-catenin, thereby attenuating the Wnt signaling effects on the nuclear translocation of ß-catenin and subsequent transactivation of the Tcf/Lef promoter. CONCLUSIONS: The results of the present study suggest that CD82/KAI1 functions in suppressing TGF-ß1 - and Wnt-induced EMT in prostate cancer cells by inhibiting the TGF-ß1 /Smad and Wnt/ß-catenin pathways. Therefore, loss or decrease of CD82 expression is likely to render prostate cancer cells prone to respond to the TGF-ß1 and Wnt signals with EMT, resulting in the development of a motile and invasive mesenchymal phenotype related to the initiation of the metastatic cascade.
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Transición Epitelial-Mesenquimal/fisiología , Proteína Kangai-1/metabolismo , Próstata/patología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Línea Celular Tumoral , Humanos , Masculino , Ratones , Invasividad Neoplásica , Metástasis de la Neoplasia , Próstata/metabolismo , Proteína Smad2/metabolismo , Vía de Señalización WntRESUMEN
Inflammatory cytokines, including tumor necrosis factor-α (TNFα), were elevated in patients with cardiovascular diseases and are also considered as crucial factors in the pathogenesis of preeclampsia; however, the underlying pathogenic mechanism has not been clearly elucidated. This study provides novel evidence that TNFα leads to endothelial dysfunction associated with hypertension and vascular remodeling in preeclampsia through down-regulation of endothelial nitric-oxide synthase (eNOS) by NF-κB-dependent biogenesis of microRNA (miR)-31-5p, which targets eNOS mRNA. In this study, we found that miR-31-5p was up-regulated in sera from patients with preeclampsia and in human endothelial cells treated with TNFα. TNFα-mediated induction of miR-31-5p was blocked by an NF-κB inhibitor and NF-κB p65 knockdown but not by mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase inhibitors, indicating that NF-κB is essential for biogenesis of miR-31-5p. The treatment of human endothelial cells with TNFα or miR-31-5p mimics decreased endothelial nitric-oxide synthase (eNOS) mRNA stability without affecting eNOS promoter activity, resulting in inhibition of eNOS expression and NO/cGMP production through blocking of the functional activity of the eNOS mRNA 3'-UTR. Moreover, TNFα and miR-31-5p mimic evoked endothelial dysfunction associated with defects in angiogenesis, trophoblastic invasion, and vasorelaxation in an ex vivo cultured model of human placental arterial vessels, which are typical features of preeclampsia. These results suggest that NF-κB-responsive miR-31-5p elicits endothelial dysfunction, hypertension, and vascular remodeling via post-transcriptional down-regulation of eNOS and is a molecular risk factor in the pathogenesis and development of preeclampsia.
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Células Endoteliales/fisiología , MicroARNs/metabolismo , Óxido Nítrico Sintasa de Tipo III/genética , Preeclampsia/metabolismo , Regiones no Traducidas 3'/genética , Animales , Arterias/efectos de los fármacos , Regulación hacia Abajo , Células Endoteliales/efectos de los fármacos , Femenino , Técnicas de Silenciamiento del Gen , Células Endoteliales de la Vena Umbilical Humana , Humanos , Masculino , Ratones Endogámicos C57BL , MicroARNs/farmacología , Subunidad p50 de NF-kappa B/genética , Subunidad p50 de NF-kappa B/metabolismo , Neovascularización Fisiológica , Placenta/irrigación sanguínea , Placenta/efectos de los fármacos , Preeclampsia/genética , Embarazo , Trofoblastos/fisiología , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/farmacologíaRESUMEN
Tetraspanin membrane proteins form physical complexes with signaling molecules and have been suggested to influence the signaling events of associated molecules. Of the tetraspanin proteins, CD82 has been shown to promote homotypic cell-cell adhesion, which partially accounts for its role in suppressing cancer invasion and metastasis. We found here that CD82-induced cell-cell adhesion is attributed to increased E-cadherin expression through CD82-mediated downregulation of the E-cadherin repressor Snail. The Snail repression by CD82 resulted from the reduced binding of the Sp1 transcription factor to the Snail gene promoter. Notably, high CD82 expression did not allow the fibronectin matrix to induce Sp1 phosphorylation, implicating CD82 inhibition of the fibronectin-integrin signaling-dependent Sp1 activation. Meanwhile, E-cadherin upregulated by CD82 pulled ß-catenin up to the membrane region, and consequently reduced the amount of cytoplasmic ß-catenin that was able to move into to the nucleus. The Wnt signal-induced nuclear translocation of ß-catenin was also inhibited by the CD82 function of upregulating E-cadherin. Overall, high CD82 expression was likely to suppress fibronectin adhesion-induced Sp1 activation signaling for Snail expression, resulting in continuous E-cadherin expression, which contributed not only to the maintenance of strong cell-cell adhesion but also to the blockage of nuclear ß-catenin signaling.
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Antígenos CD/metabolismo , Cadherinas/metabolismo , Adhesión Celular , Proteína Kangai-1/fisiología , Neoplasias de la Próstata/metabolismo , Factores de Transcripción de la Familia Snail/metabolismo , Factor de Transcripción Sp1/metabolismo , beta Catenina/metabolismo , Línea Celular Tumoral , Fibronectinas/metabolismo , Humanos , Integrinas/metabolismo , Masculino , Vía de Señalización WntRESUMEN
The regulatory role of suppressor of cytokine signaling 1 (SOCS1) in inflammation has been reported. However, its role in allergic inflammation has not been previously reported. SOCS1 mediated in vitro and in vivo allergic inflammation. Histone deacetylase-3 (HDAC3), a mediator of allergic inflammation, interacted with SOCS1, and miR-384 inhibitor, a positive regulator of HDAC3, induced features of allergic inflammation in an SOCS1-dependent manner. miRNA array analysis showed that the expression of miR-122 was decreased by antigen-stimulation. TargetScan analysis predicted the binding of miR-122 to the 3'-UTR of SOCS1. miR-122 inhibitor induced in vitro and in vivo allergic features in SOCS1-dependent manner. SOCS1 was necessary for allergic inflammation-promoted enhanced tumorigenic and metastatic potential of cancer cells. SOCS1 and miR-122 regulated cellular interactions involving cancer cells, mast cells and macrophages during allergic inflammation. SOCS1 mimetic peptide, D-T-H-F-R-T-F-R-S-H-S-D-Y-R-R-I, inhibited in vitro and in vivo allergic inflammation, allergic inflammation-promoted enhanced tumorigenic and metastatic potential of cancer cells, and cellular interactions during allergic inflammation. Janus kinase 2 (JAK2) exhibited binding to SOCS1 mimetic peptide and mediated allergic inflammation. Transforming growth factor- Δ1 (TGF-Δ1) was decreased during allergic inflammation and showed an anti-allergic effect. SOCS1 and JAK2 regulated the production of anti-allergic TGF-Δ1. Taken together, our results show that miR-122-SOCS1 feedback loop can be employed as a target for the development of anti-allergic and anti-cancer drugs.
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Ligation of the death receptors for TNF-α, FasL, and TRAIL triggers two common pathways, caspase-dependent intrinsic apoptosis and intracellular reactive oxygen species (ROS) generation. The apoptotic pathway is well characterized; however, a signaling linker between the death receptor and ROS production has not been clearly elucidated. Here, we found that death receptor-induced ROS generation was strongly inhibited by mitochondrial complex I and II inhibitors, but not by inhibitors of NADPH oxidase, lipoxygenase, cyclooxygenase or xanthine oxidase, indicating that ROS are mostly generated by the impairment of the mitochondrial respiratory chain. ROS generation was accompanied by caspase-8 activation, Bid cleavage, and cytochrome c release; it was blocked in FADD- and caspase-8-deficient cells, as well as by caspase-8 knockdown and inhibitor. Moreover, Bid knockdown abrogated TNF-α- or TRAIL-induced ROS generation, whereas overexpression of truncated Bid (tBid) or knockdown of cytochrome c spontaneously elevated ROS production. In addition, p53-overexpressing cells accumulated intracellular ROS via cytochrome c release mediated by the BH3-only protein Noxa induction. In a cell-free reconstitution system, caspase-8-mediated Bid cleavage and recombinant tBid induced mitochondrial cytochrome c release and ROS generation, which were blocked by Bcl-xL and antioxidant enzymes. These data suggest that anti-apoptotic Bcl-2 proteins play an important role in mitochondrial ROS generation by preventing cytochrome c release. These data provide evidence that the FADD/caspase-8/Bid/cytochrome c axis is a crucial linker between death receptors and mitochondria, where they play a role in ROS generation and apoptosis.
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Proteína Proapoptótica que Interacciona Mediante Dominios BH3/genética , Caspasa 8/genética , Citocromos c/genética , Mitocondrias Hepáticas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Animales , Apoptosis/genética , Proteína Proapoptótica que Interacciona Mediante Dominios BH3/metabolismo , Caspasa 8/metabolismo , Línea Celular Tumoral , Citocromos c/metabolismo , Proteína de Dominio de Muerte Asociada a Fas/genética , Proteína de Dominio de Muerte Asociada a Fas/metabolismo , Regulación de la Expresión Génica , Células HeLa , Humanos , Células Jurkat , Hígado/citología , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal , Ligando Inductor de Apoptosis Relacionado con TNF/genética , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismoRESUMEN
While wild goose populations wintering in North America and Europe are mostly flourishing by exploiting farmland, those in China (which seem confined to natural wetlands) are generally declining. Telemetry devices were attached to 67 wintering wild geese of five different species at three important wetlands in the Yangtze River Floodplain (YRF), China to determine habitat use. 50 individuals of three declining species were almost entirely diurnally confined to natural wetlands; 17 individuals from two species showing stable trends used wetlands 83% and 90% of the time, otherwise resorting to farmland. These results confirm earlier studies linking declines among Chinese wintering geese to natural habitat loss and degradation affecting food supply. These results also contribute to explaining the poor conservation status of Chinese wintering geese compared to the same and other goose species wintering in adjacent Korea and Japan, western Europe and North America, which feed almost entirely on agricultural land, liberating them from winter population limitation.
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Conservación de los Recursos Naturales , Ecosistema , Gansos/fisiología , Animales , China , Gansos/clasificación , Dinámica Poblacional , Estaciones del AñoRESUMEN
Extrahepatic cholangiocarcinoma (ECC), a malignant tumor of biliary origin, has a poor prognosis with limited treatment options. The KRAS oncogene is the most commonly mutated gene in ECC and one of the factors that predicts a poor prognosis and low survival rate. L1 cell adhesion molecule (L1CAM) is expressed in ECC cells and acts as an independent poor prognostic factor in predicting patient survival. In this study we investigate the functional significance of L1CAM in ECC cells with activating KRAS mutation. We selected an ECC cell line, EGI-1, with activating KRAS mutation, and then confirmed its expression of L1CAM by RT-PCR, western blot analysis, and flow cytometry. The suppression of L1CAM expression (using a specific lentivirus-delivered shRNA) significantly decreased the migratory and invasive properties of EGI-1 cells, without altering their proliferation or survival. Analyses of signaling effectors in L1CAM-depleted and control EGI-1 cells indicated that L1CAM suppression decreased the levels of both phosphorylated MKK4 and total MKK4, together with c-Jun N-terminal kinase (JNK) phosphorylation. Further, exposure to a JNK inhibitor (SP600125) decreased migration and invasion of EGI-1 cells. These results suggest that L1CAM promotes cellular migration and invasion via the induction of MKK4 expression, leading to JNK activation. Our study is the first to demonstrate a functional role for L1CAM in ECC carrying the activating KRAS mutation. Given that KRAS is the most commonly mutated oncogene in ECC, L1CAM may serve as an attractive therapeutic target for ECC cells with activating KRAS mutation.
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Neoplasias de los Conductos Biliares/patología , Colangiocarcinoma/patología , Sistema de Señalización de MAP Quinasas/genética , Molécula L1 de Adhesión de Célula Nerviosa/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Antracenos/farmacología , Neoplasias de los Conductos Biliares/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular/genética , Colangiocarcinoma/metabolismo , Activación Enzimática , Técnicas de Silenciamiento del Gen , Humanos , MAP Quinasa Quinasa 4/antagonistas & inhibidores , MAP Quinasa Quinasa 4/metabolismo , Mutación , Molécula L1 de Adhesión de Célula Nerviosa/genética , Inhibidores de Proteínas Quinasas/farmacología , ARN Interferente Pequeño/genéticaRESUMEN
The human CD99 protein is a 32-kDa glycosylated transmembrane protein that regulates various cellular responses, including cell adhesion and leukocyte extravasation. We previously reported that CD99 activation suppresses ß1 integrin activity through dephosphorylation of focal adhesion kinase (FAK) at Y397. We explored a molecular mechanism underlying the suppression of ß1 integrin activity by CD99 agonists and its relevance to tumor growth in vivo CD99-Fc fusion proteins or a series of CD99-derived peptides suppressed ß1 integrin activity by specifically interacting with three conserved motifs of the CD99 extracellular domain. CD99CRIII3, a representative CD99-derived 3-mer peptide, facilitated protein kinase A-SHP2 interaction and subsequent activation of the HRAS/RAF1/MEK/ERK signaling pathway. Subsequently, CD99CRIII3 induced FAK phosphorylation at S910, which led to the recruitment of PTPN12 and PIN1 to FAK, followed by FAK dephosphorylation at Y397. Taken together, these results indicate that CD99-derived agonist ligands inhibit fibronectin-mediated ß1 integrin activation through the SHP2/ERK/PTPN12/FAK signaling pathway.
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Adhesión Celular/fisiología , Movimiento Celular/fisiología , Fibronectinas/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Cadenas beta de Integrinas/metabolismo , Transducción de Señal , Antígeno 12E7/metabolismo , Línea Celular Tumoral , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Ligandos , Fosforilación , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 12/metabolismo , Transducción de Señal/fisiologíaRESUMEN
Preeclampsia is an inflammatory disease with endothelial cell dysfunction that occurs via decreased endothelial nitric oxide synthase/nitric oxide (eNOS/NO) activity. Aspirin reduces the incidence of hypertensive pregnancy complications. However, the underlying mechanism has not been clearly explained. Here, we found that tumor necrosis factor (TNF)-α, microRNA (miR)-155, and eNOS levels as well as endothelial redox phenotype were differentially regulated in preeclamptic patients, implying the involvement of TNF-α- and redox signal-mediated miR-155 biogenesis and eNOS downregulation in the pathogenesis of preeclampsia. Aspirin prevented the TNF-α-mediated increase in miR-155 biogenesis and decreases in eNOS expression and NO/cGMP production in cultured human umbilical vein endothelial cells (HUVECs). Similar effects of aspirin were also observed in HUVECs treated with H2O2. The preventive effects of aspirin was associated with the inhibition of nuclear factor-κB (NF-κB)-dependent MIR155HG (miR-155 host gene) expression. Aspirin recovered the TNF-α-mediated decrease in wild-type, but not mutant, eNOS 3'-untranslated region reporter activity, whose effect was blocked by miR-155 mimic. Moreover, aspirin prevented TNF-α-mediated endothelial cell dysfunction associated with impaired vasorelaxation, angiogenesis, and trophoblast invasion, and the preventive effects were blocked by miR-155 mimic or an eNOS inhibitor. Aspirin rescued TNF-α-mediated eNOS downregulation coupled with endothelial dysfunction by inhibiting NF-κB-dependent transcriptional miR-155 biogenesis. Thus, the redox-sensitive NF-κB/miR-155/eNOS axis may be crucial in the pathogenesis of vascular disorders including preeclampsia.
Asunto(s)
Aspirina/administración & dosificación , MicroARNs/genética , Óxido Nítrico Sintasa de Tipo III/genética , Preeclampsia/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/genética , Adulto , Células Endoteliales/efectos de los fármacos , Células Endoteliales/patología , Femenino , Células Endoteliales de la Vena Umbilical Humana , Humanos , FN-kappa B/genética , Preeclampsia/metabolismo , Preeclampsia/patología , Embarazo , Transducción de Señal , Transfección , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
The tetrapeptide Arg-Leu-Tyr-Glu (RLYE) is known to inhibit vascular endothelial growth factor-A (VEGF-A)-induced angiogenesis in vitro. Herein, we examined its underlying mechanism and antitumor activity associated with vascular remodeling. RLYE inhibited VEGF-A-induced angiogenesis in a mouse model and suppressed VEGF-A-induced angiogenic signal cascades in human endothelial cells. However, RLYE showed no inhibitory effect on VEGF-A-induced proliferation and migration of multiple myeloma cells expressing VEGF receptor (VEGFR)-1, but not VEGFR-2. In addition, RLYE showed no inhibitory effect on angiogenic activities induced by VEGF-B, basic fibroblast growth factor, epithermal growth factor, sphingosine-1-phosphate, and placental growth factor. RLYE bound specifically to VEGFR-2 at the VEGF-A binding site, thereby blocking VEGF-A-VEGFR-2 binding and VEGF-A-induced VEGFR-2 internalization. The RLYE peptide inhibited tumor growth and metastasis via suppression of tumor angiogenesis in tumor-bearing mice. Moreover, RLYE showed a synergistic effect of the cytotoxic agent irinotecan on tumor cell apoptosis and tumor progression via tumor vessel normalization due to stabilization of VE-cadherin-mediated adherens junction, improvement of pericyte coverage, and inhibition of vascular leakage in tumors. Our results suggest that RLYE can be used as an antiangiogenic and tumor blood vessel remodeling agent for inhibition of tumor growth and metastasis by antagonizing VEGFR-2, with the synergistic anti-cancer effect via enhancement of drug delivery and therapeutic efficacy.
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Inhibidores de la Angiogénesis/farmacología , Neoplasias del Colon/tratamiento farmacológico , Melanoma Experimental/tratamiento farmacológico , Oligopéptidos/farmacología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Permeabilidad Capilar/efectos de los fármacos , Neoplasias del Colon/irrigación sanguínea , Neoplasias del Colon/metabolismo , Progresión de la Enfermedad , Células HCT116 , Humanos , Masculino , Melanoma Experimental/irrigación sanguínea , Melanoma Experimental/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Neovascularización Patológica/tratamiento farmacológico , Ratas Sprague-Dawley , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismoRESUMEN
We previously reported the role of cancer/testis antigen CAGE in the response to anti-cancer drugs. CAGE increased the expression of cyclinD1, and pGSK3ßSer9, an inactive GSK3ß, while decreasing the expression of phospho-cyclinD1Thr286. CAGE showed binding to GSK3ß and the domain of CAGE (amino acids 231-300) necessary for binding to GSK3ß and for the expression regulation of cyclinD1 was determined. 269GTGKT273 peptide, corresponding to the DEAD box helicase domain of CAGE, decreased the expression of cyclinD1 and pGSK3ßSer9 while increasing the expression of phospho-cyclinD1Thr286. GTGKT peptide showed the binding to CAGE and prevented CAGE from binding to GSK3ß. GTGKT peptide changed the localization of CAGE and inhibited the binding of CAGE to the promoter sequences of cyclin D1. GTGKT peptide enhanced the apoptotic effects of anti-cancer drugs and decreased the migration, invasion, angiogenic, tumorigenic and metastatic potential of anti-cancer drug-resistant cancer cells. We found that Lys272 of GTGKT peptide was necessary for conferring anti-cancer activity. Peptides corresponding to the DEAD box helicase domain of CAGE, such as AQTGTGKT, QTGTGKT and TGTGKT, also showed anti-cancer activity by preventing CAGE from binding to GSK3ß. GTGKT peptide showed ex vivo tumor homing potential. Thus, peptides corresponding to the DEAD box helicase domain of CAGE can be developed as anti-cancer drugs in cancer patients expressing CAGE.
Asunto(s)
Antineoplásicos/farmacología , Ciclina D1/biosíntesis , ARN Helicasas DEAD-box/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3 beta/antagonistas & inhibidores , Oligopéptidos/farmacología , Secuencia de Aminoácidos , Animales , Línea Celular Tumoral , Movimiento Celular/fisiología , Ciclina D1/genética , ARN Helicasas DEAD-box/metabolismo , Resistencia a Antineoplásicos , Femenino , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Regiones Promotoras Genéticas , Dominios ProteicosRESUMEN
BACKGROUND: Repression of the KAI1 metastasis suppressor gene is closely associated with malignancy and poor prognosis in many human cancer types including prostate cancer. Since gene repression in human cancers frequently results from epigenetic alterations by DNA methylation and histone modifications, we examined whether the KAI1 gene becomes silenced through these epigenetic mechanisms in prostate cancer. METHODS: KAI1 mRNA and protein levels were determined by RT-PCR and immunoblotting analyses, respectively. Methylation status of the KAI1 promoter DNA in prostate cancer cell lines and tissues was evaluated by methylation-specific PCR analysis of bisulfite-modified genomic DNAs. Methylated CpG sites in the KAI1 promoter were identified by sequencing the PCR clones of the bisulfite-modified KAI1 promoter DNA. KAI1 protein levels in human prostate cancer tissue samples were examined by immunofluorescence staining of the tissues with an anti-KAI1 antibody. RESULTS: Among the three human prostate cancer cell lines examined, PC3 and DU145 cells exhibited markedly decreased levels of KAI1 mRNA and protein as compared to LNCaP cells, even though the exogenous KAI1 promoter not being methylated was normally functional in all these cell lines. Treatment of the low KAI1-expressing cell lines with a demethylating agent, 5'-aza-2'-deoxycytidine, significantly elevated KAI1 expression levels, implicating the involvement of DNA methylation in KAI1 downregulation. Methylation of CpG islands within the KAI1 promoter region was observed in the low KAI1-expressing cells, but not in the high KAI1-expressing cells. Also, methyl CpG-binding proteins such as MBD2 and MeCP2 were complexed to the KAI1 promoter in the low KAI1-expressing cells. Bisulfite sequencing analysis identified the intensively methylated CpG residues in the KAI1 promoter clones derived from prostate cancer cells and tissues with no or low KAI1 expression. As in prostate cancer cell lines, prostate cancer tissues from patients also displayed a negative association between KAI1 expression levels and methylation status of the KAI1 promoter. CONCLUSIONS: The present data suggest that the KAI1 gene might be repressed by epigenetic alterations through the promoter CpG-site methylation during prostate cancer progression. This epigenetic mechanism could provide a clue for understanding how the KAI1 gene was silenced in metastatic prostate cancers. Prostate 77: 350-360, 2017. © 2016 Wiley Periodicals, Inc.