Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Int J Mol Sci ; 24(22)2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-38003288

RESUMEN

We describe a strategy for the development of a rational approach of neoplastic disease therapy based on the demonstration that scale-free networks are susceptible to specific attacks directed against its connective hubs. This strategy involves the (i) selection of up-regulated hubs of connectivity in the tumors interactome, (ii) drug repurposing of these hubs, (iii) RNA silencing of non-druggable hubs, (iv) in vitro hub validation, (v) tumor-on-a-chip, (vi) in vivo validation, and (vii) clinical trial. Hubs are protein targets that are assessed as targets for rational therapy of cancer in the context of personalized oncology. We confirmed the existence of a negative correlation between malignant cell aggressivity and the target number needed for specific drugs or RNA interference (RNAi) to maximize the benefit to the patient's overall survival. Interestingly, we found that some additional proteins not generally targeted by drug treatments might justify the addition of inhibitors designed against them in order to improve therapeutic outcomes. However, many proteins are not druggable, or the available pharmacopeia for these targets is limited, which justifies a therapy based on encapsulated RNAi.


Asunto(s)
Neoplasias , Mapeo de Interacción de Proteínas , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/genética
2.
Crit Care ; 26(1): 297, 2022 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-36175982

RESUMEN

BACKGROUND: The ventilatory ratio (VR, [minute ventilation × PaCO2]/[predicted body weight × 100 × 37.5]) is associated with mortality in ARDS. The aims of this study were to test whether baseline disease severity or neuromuscular blockade (NMB) modified the relationship between VR and mortality. METHODS: This was a post hoc analysis of the PETAL-ROSE trial, which randomized moderate-to-severe ARDS patients to NMB or control. Survival among patients with different VR trajectories or VR cutoff above and below the median was assessed by Kaplan-Meier analysis. The relationships between single-day or 48-h VR trajectories with 28- or 90-day mortality were tested by logistic regression. Randomization allocation to NMB and markers of disease severity were tested as confounders by multivariable regression and interaction term analyses. RESULTS: Patients with worsening VR trajectories had significantly lower survival compared to those with improving VR (n = 602, p < 0.05). Patients with VR > 2 (median) at day 1 had a significantly lower 90-day survival compared to patients with VR ≤ 2 (HR 1.36, 95% CI 1.10-1.69). VR at day 1 was significantly associated with 28-day mortality (OR = 1.40, 95% CI 1.15-1.72). There was no interaction between NMB and VR for 28-day mortality. APACHE-III had a significant interaction with VR at baseline for the outcome of 28-day mortality, such that the relationship between VR and mortality was stronger among patients with lower APACHE-III. There was a significant association between rising VR trajectory and mortality that was independent of NMB, baseline PaO2/FiO2 ratio and generalized markers of disease severity (Adjusted OR 1.81, 95% CI 1.28-2.84 for 28-day and OR 2.07 95% CI 1.41-3.10 for 90-day mortality). APACHE-III and NMB were not effect modifiers in the relationship between VR trajectory and mortality. CONCLUSIONS: Elevated baseline and day 1 VR were associated with higher 28-day mortality. The relationship between baseline VR and mortality was stronger among patients with lower APACHE-III. APACHE-III was not an effect modifier for the relationship between VR trajectory and mortality, so that the VR trajectory may be optimally suited for prognostication and predictive enrichment. VR was not different between patients randomized to NMB or control, indicating that VR can be utilized without correcting for NMB.


Asunto(s)
Bloqueo Neuromuscular , Síndrome de Dificultad Respiratoria , APACHE , Humanos , Estimación de Kaplan-Meier , Pronóstico , Síndrome de Dificultad Respiratoria/terapia
3.
Crit Care ; 25(1): 271, 2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34344416

RESUMEN

BACKGROUND: Acute respiratory failure (ARF) can progress to acute respiratory distress syndrome and death. Biomarkers may allow for risk stratification and prognostic enrichment in ARF. Thrombomodulin (TM) is a transmembrane antithrombotic mediator expressed in endothelial cells. It is cleaved into its soluble form (sTM) during inflammation and vascular injury. Levels of sTM correlate with inflammation and end organ dysfunction. METHODS: This was a prospective observational study of 432 patients aged 2 weeks-17 years requiring invasive mechanical ventilation. It was ancillary to the multicenter clinical trial, Randomized Evaluation of Sedation Titration for Respiratory Failure (RESTORE). After consent, patients had up to 3 plasma samples collected at 24-h intervals within 5 days after intubation. sTM was assayed by ELISA. The Hazard ratio (HR) for 90-day mortality was determined by Cox regression. Mixed effect models (MEM) were used to test for association with extrapulmonary multiorgan failure (MOF) and oxygenation index (OI). Age, race, sex and PRISM-III scores were used as confounding variables for multivariable analyses. RESULTS: sTM values ranged from 16.6 to 670.9 ng/ml within 5 days after intubation. Higher sTM was associated with increased 90-day mortality (n = 432, adjusted HR = 1.003, p = 0.02) and worse OI in the first 5 days after intubation (n = 252, Estimate = 0.02, p < 0.01). Both initial and slope of sTM were associated with increased extrapulmonary MOF in unadjusted and adjusted analyses (Intercept, Estimate = 0.003, p < 0.0001; and slope, Estimate = 0.01, p = 0.0009, n = 386). CONCLUSIONS: Plasma sTM is associated with mortality, severity of hypoxic respiratory failure and worsening extrapulmonary MOF in children with ARF. This suggests a role of vascular injury in the pathogenesis of ARF and provides potential applicability towards targeted therapies. TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT00814099 . In healthy lung endothelium, thrombomodulin (TM) recruits thrombin to activate Protein-C (PC/APC), that inhibits plasminogen activator-1 (PAI-1) and thrombosis. In inflamed and damaged endothelium, TM is cleaved into its soluble form (sTM), precluding its usual regulation of thrombosis. In this study, we measured plasma sTM levels in pediatric patients with respiratory failure and found that sTM correlated with mortality and other clinical markers of poor outcomes.


Asunto(s)
Mortalidad/tendencias , Trombomodulina/análisis , Biomarcadores , Femenino , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia Multiorgánica , Pronóstico , Respiración Artificial , Insuficiencia Respiratoria
5.
Exp Cell Res ; 351(2): 173-181, 2017 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-28034672

RESUMEN

Mechanical properties of cells are known to be influenced by the actin cytoskeleton. In this article, the action of drugs that interact with the actin cortex is investigated by tether extraction and rheology experiments using optical tweezers. The influences of Blebbistatin, Cytochalasin D and Jasplakinolide on the cell mechanical properties are evaluated. The results, in contradiction to current views for Jasplakinolide, show that all three drugs and treatments destabilize the actin cytoskeleton, decreasing the cell membrane tension. The cell membrane bending modulus increased when the actin cytoskeleton was disorganized by Cytochalasin D. This effect was not observed for Blebbistatin and Jasplakinolide. All drugs decreased by two-fold the cell viscoelastic moduli, but only Cytochalasin D was able to alter the actin network into a more fluid-like structure. The results can be interpreted as the interplay between the actin network and the distribution of myosins as actin cross-linkers in the cytoskeleton. This information may contribute to a better understanding of how the membrane and cytoskeleton are involved in cell mechanical properties, underlining the role that each one plays in these properties.


Asunto(s)
Citoesqueleto de Actina/efectos de los fármacos , Citocalasina D/farmacología , Depsipéptidos/farmacología , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Miosinas/química , Citoesqueleto de Actina/química , Citoesqueleto de Actina/ultraestructura , Animales , Fenómenos Biomecánicos , Membrana Celular/química , Membrana Celular/efectos de los fármacos , Membrana Celular/ultraestructura , Elasticidad/efectos de los fármacos , Humanos , Ratones , Células 3T3 NIH , Pinzas Ópticas , Reología , Viscosidad/efectos de los fármacos
6.
J Immunol ; 193(7): 3613-23, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25187655

RESUMEN

Complement and the kallikrein-kinin cascade system are both activated in injured tissues. Little is known about their partnership in the immunopathogenesis of Chagas disease, the chronic infection caused by the intracellular protozoan Trypanosoma cruzi. In this study, we show that pharmacological targeting of the C5a receptor (C5aR) or the bradykinin B2 receptor (B2R) inhibited plasma leakage in hamster cheek pouch topically exposed to tissue culture trypomastigotes (TCTs). Further, angiotensin-converting enzyme inhibitors potentiated TCT-evoked paw edema in BALB/c, C57BL/6, and C5-deficient A/J mice through activation of joint pathways between C5aR/B2R or C3aR/B2R. In addition to generation of C5a and kinins via parasite-derived cruzipain, we demonstrate that macrophages internalize TCTs more efficiently through joint activation of C5aR/B2R. Furthermore, we found that C5aR targeting markedly reduces NO production and intracellular parasitism in macrophages. We then studied the impact of C5aR/B2R cross-talk in TCT infection on the development of adaptive immunity. We found that IL-12p40/70 expression was blunted in splenic dendritic cells by blocking either C5aR or B2R, suggesting that codominant signaling via C5aR and B2R fuels production of the Th1-polarizing cytokine. Finally, we assessed the impact of kinins and C5a liberated in parasite-laden tissues on Th cell differentiation. As predicted, BALB/c mice pretreated with angiotensin-converting enzyme inhibitors potentiated IFN-γ production by Ag-specific T cells via C5aR/B2R cross-talk. Interestingly, we found that B2R targeting upregulated IL-10 secretion, whereas C5aR blockade vigorously stimulated IL-4 production. In summary, we describe a novel pathway by which C5aR/B2R cross-talk couples transendothelial leakage of plasma proteins to the cytokine circuitry that coordinates antiparasite immunity.


Asunto(s)
Inmunidad Adaptativa , Enfermedad de Chagas/inmunología , Inmunidad Innata , Receptor de Anafilatoxina C5a/inmunología , Receptor de Bradiquinina B2/inmunología , Células TH1/inmunología , Trypanosoma cruzi/inmunología , Animales , Antígenos de Protozoos/genética , Antígenos de Protozoos/inmunología , Enfermedad de Chagas/genética , Enfermedad de Chagas/patología , Complemento C5a/genética , Complemento C5a/inmunología , Cricetinae , Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/inmunología , Citocinas/genética , Citocinas/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Proteínas Protozoarias , Receptor de Anafilatoxina C5a/genética , Receptor de Bradiquinina B2/genética , Células TH1/patología , Trypanosoma cruzi/genética
7.
Cureus ; 16(3): e55573, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38576627

RESUMEN

This narrative review explores the application of point-of-care ultrasound (POCUS) in palliative care and its feasibility in home care settings. POCUS has the potential to streamline diagnostic strategies without patient transfer to the hospital, expedite timely symptomatic relief, and reduce complications from specific palliative interventions. The advent of handheld ultrasound devices has made it an attractive diagnostic and interventional adjunct in acute palliative care. POCUS has gained widespread acceptance as part of routine care in emergency medicine and intensive care, guiding certain procedures and increasing their safety. The modernization and miniaturization of ultrasound equipment have made ultra-portable devices available, allowing for better-quality images at affordable prices. Handheld devices have the potential to revolutionize everyday clinical practice in home-based palliative care, contributing to important bedside clinical decisions. Palliative care patients often require diagnostic examinations in the last months of their lives, with CT being the most frequently performed imaging procedure. However, CT imaging is associated with high costs and burdens, leading to increased suffering and impaired quality of life. Clinical ultrasound, a dialogic imaging modality, offers a safer and more efficient approach to palliative care. POCUS applications, which are cost-effective, non-invasive, and well-tolerated, can be used to improve patient satisfaction and diagnostic understanding. POCUS is a valuable tool in palliative care, improving diagnostic accuracy and reducing the time to diagnosis for various pathologies. It is a standard of care for many procedures and improves patient safety. However, there are limitations to POCUS in palliative care, such as operator-dependent examination variability and limited availability of trained professionals. To overcome these limitations, palliative care physicians should receive mandatory training in POCUS, which can be incorporated into the core curriculum. Additionally, ultrasound teleconsulting can assist less experienced examiners in real-time examinations. The literature on POCUS in palliative care is limited, but research on patient-oriented outcomes is crucial. POCUS should be considered a supplement to good clinical reasoning and regulated radiological evaluations.

8.
J Clin Periodontol ; 40(7): 653-60, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23534940

RESUMEN

AIM: The pathophysiology of periodontal diseases involves aspects of immunity and bone remodelling. Considering the role of the kinin B1 receptor (Bdkrb1) in inflammation and healing, the purpose of this study was to evaluate the contribution of Bdkrb1 to the pathogenesis of periodontitis. MATERIAL AND METHODS: We used a model of ligature-induced experimental periodontitis (LIEP) in mice lacking Bdkrb1 (Bdkrb1(-/-) ) to test the role of this receptor in bone loss and cytokine secretion by lymph nodes cells. Angiotensin-converting enzyme inhibitor (ACEi) was used as a pharmacological strategy to support the genetic model. Also, autonomous effect of Bdkrb1 deletion was evaluated in osteoclasts precursors from bone marrow. RESULTS: Bdkrb1(-/-) mice exhibit increased bone loss and IL-17 secretion in response to LIEP when compared to wild type. LIEP does not modify TNF-α, IFN-γ and IL-10 levels in Bdkrb1(-/-) mice after 21 days. Bone marrow cells from Bdkrb1(-/-) displayed increased differentiation into functional osteoclasts with consistent artificial calcium phosphate degradation. Furthermore, treatment of mice with ACEi prevented bone destruction. CONCLUSION: Bdkrb1 participates in the pathogenesis of LIEP bone loss possibly through mechanisms that involve modulation of the TH 17 response, thereby demonstrating its role in the development of periodontitis.


Asunto(s)
Pérdida de Hueso Alveolar/patología , Osteoclastos/patología , Periodontitis/etiología , Receptor de Bradiquinina B1/fisiología , Pérdida de Hueso Alveolar/etiología , Pérdida de Hueso Alveolar/prevención & control , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Animales , Células de la Médula Ósea/patología , Fosfatos de Calcio/metabolismo , Recuento de Células , Diferenciación Celular/fisiología , Forma de la Célula , Células Cultivadas , Enalapril/uso terapéutico , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Periodontitis/patología , Ratas , Ratas Wistar , Receptor de Bradiquinina B1/genética , Linfocitos T/fisiología , Células Th17/fisiología , Factor de Necrosis Tumoral alfa/metabolismo
9.
Adv Healthc Mater ; 11(11): e2102305, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35158409

RESUMEN

Organ-on-a-chip in vitro platforms accurately mimic complex microenvironments offering the ability to recapitulate and dissect mechanisms of physiological and pathological settings, revealing their major importance to develop new therapeutic targets. Bone diseases, such as osteoarthritis, are extremely complex, comprising of the action of inflammatory mediators leading to unbalanced bone homeostasis and de-regulation of sensory innervation and angiogenesis. Although there are models to mimic bone vascularization or innervation, in vitro platforms merging the complexity of bone, vasculature, innervation, and inflammation are missing. Therefore, in this study a microfluidic-based neuro-vascularized bone chip (NVB chip) is proposed to 1) model the mechanistic interactions between innervation and angiogenesis in the inflammatory bone niche, and 2) explore, as a screening tool, novel strategies targeting inflammatory diseases, using a nano-based drug delivery system. It is possible to set the design of the platform and achieve the optimized conditions to address the neurovascular network under inflammation. Moreover, this system is validated by delivering anti-inflammatory drug-loaded nanoparticles to counteract the neuronal growth associated with pain perception. This reliable in vitro tool will allow understanding the bone neurovascular system, enlightening novel mechanisms behind the inflammatory bone diseases, bone destruction, and pain opening new avenues for new therapies discovery.


Asunto(s)
Enfermedades Óseas , Osteoartritis , Humanos , Inflamación , Dispositivos Laboratorio en un Chip , Microfluídica , Neovascularización Patológica/patología
10.
J Immunol ; 183(6): 3700-11, 2009 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-19687097

RESUMEN

Porphyromonas gingivalis, a Gram-negative bacterium that causes periodontitis, activates the kinin system via the cysteine protease R-gingipain. Using a model of buccal infection based on P. gingivalis inoculation in the anterior mandibular vestibule, we studied whether kinins released by gingipain may link mucosal inflammation to T cell-dependent immunity through the activation of bradykinin B(2) receptors (B(2)R). Our data show that P. gingivalis W83 (wild type), but not gingipain-deficient mutant or wild-type bacteria pretreated with gingipain inhibitors, elicited buccal edema and gingivitis in BALB/c or C57BL/6 mice. Studies in TLR2(-/-), B(2)R(-/-), and neutrophil-depleted C57BL/6 mice revealed that P. gingivalis induced edema through the sequential activation of TLR2/neutrophils, with the initial plasma leakage being amplified by gingipain-dependent release of vasoactive kinins from plasma-borne kininogens. We then used fimbriae (Fim) Ag as a readout to verify whether activation of the TLR2-->PMN-->B(2)R axis (where PMN is polymorphonuclear neutrophil) at early stages of mucosal infection had impact on adaptive immunity. Analyzes of T cell recall responses indicated that gingipain drives B(2)R-dependent generation of IFN-gamma-producing Fim T cells in submandibular draining lymph nodes of BALB/c and C57BL/6 mice, whereas IL-17-producing Fim T cells were generated only in BALB/c mice. In summary, our studies suggest that two virulence factors, LPS (an atypical TLR2 ligand) and gingipain, forge a trans-cellular cross-talk between TLR2 and B(2)R, thus forming an innate axis that guides the development of Fim-specific T cells in mice challenged intrabuccally by P. gingivalis. Ongoing research may clarify whether kinin-driven modulation of T cell responses may also influence the severity of chronic periodontitis.


Asunto(s)
Adhesinas Bacterianas/metabolismo , Cisteína Endopeptidasas/metabolismo , Fimbrias Bacterianas/inmunología , Interferón gamma/biosíntesis , Interleucina-17/biosíntesis , Cininas/metabolismo , Porphyromonas gingivalis/inmunología , Receptor de Bradiquinina B2/metabolismo , Linfocitos T/metabolismo , Receptor Toll-Like 2/metabolismo , Animales , Cisteína-Endopeptidasas Gingipaínas , Inmunidad , Inflamación , Ratones , Mucosa Bucal/microbiología , Mucosa Bucal/patología , Péptido Hidrolasas , Transducción de Señal , Linfocitos T/inmunología
11.
Bone ; 150: 116014, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34022456

RESUMEN

Before bone colonization, immune cells primed by breast primary tumor cells actively modify the bone microenvironment, disturbing the complex and tightly homeostatic signaling network regulated by osteoblasts and osteoclasts. Indeed, we have shown that RANKL+ CD4+ T cells specific for the 4T1 mammary carcinoma cell line, arrive at the bone marrow (BM) before metastatic cells and set the pre-metastatic niche. In the absence of RANKL expressed by T cells, there is no pre-metastatic osteolytic disease and bone metastases are blocked. Adding to the role of T cells, we have recently demonstrated that dendritic cells (DCs) provide a positive feedback loop to the osteolytic profile induced by the metastatic tumor. In this setting, DCs are able to differentiate into potent bone resorbing osteoclast-like cells keeping their antigen-presenting cell (APC) properties to maintain RANKL+ CD4+ Th17 T cells activities, via IL-23 expression. Here we show that 67NR non-metastatic tumor cells, a sibling of 4T1 tumor cell line, induce an increase in trabecular bone mass on day 11 post-tumor implant. This observation was associated with an expansion of the osteoblastic lineage cells accompanied by a reduction of osteoclasts numbers. Moreover, BM derived CD8+ T cells from 67NR tumor-bearing mice, express an anti-osteoclastogenic cytokine milieu enriched by IFN-γ, IL-10 and producing low levels of RANKL. The frequency of BM derived CD8+ FoxP3+ regulatory T cells, known as potent suppressors of osteoclastogenesis both in vitro and in vivo, was also increased in such animals. This milieu was capable to suppress 4T1 tumor-specific CD4+ T cells phenotype in vivo and in vitro and strongly inhibited bone metastases establishment, restoring trabecular bone mass volume. We concluded that the 67NR+ tumor derived CD8+ T cells phenotypes, either contributing to bone homeostasis and/or control of 4T1 breast tumor pre-metastatic disease, interfere with osteoclasts and osteoblasts activities inside BM. Our study highlights the opposing roles of subverted tumor CD4+ and CD8+ T cell subtypes in directing breast cancer progression and bone metastases establishment. For non-metastatic tumors, the role of T cells regarding bone remodeling has never been addressed before. As far as we know, this is the first description that an in situ carcinoma can modify distant sites. In the case showed here, modification of the distant bone site disfavors pre-metastatic bone niche formation.


Asunto(s)
Neoplasias Óseas , Neoplasias de la Mama , Animales , Huesos , Linfocitos T CD8-positivos , Línea Celular Tumoral , Femenino , Homeostasis , Humanos , Ratones , Osteoclastos , Microambiente Tumoral
12.
Bone ; 143: 115755, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33217627

RESUMEN

Bone metastases occur in 70% of patients with advanced breast cancer, causing severe morbidity and increased mortality due to osteolytic lesions driven by osteoclasts (OCs) inside the bone marrow (BM) microenvironment. A reciprocal vicious cycle between bone remodeling system and the tumor itself is established by the release of growth factors stored in the mineralized matrix, which in turn feed the tumor, changing tumor behavior and growth. However, BM is not a passive host microenvironment for circulating tumor cells, but instead can be actively modified by the primary tumor before metastatic spread occurs. Indeed, we have shown that T cells specific for the 4T1 mammary carcinoma cell line, are characteristically RANKL+ IL-17F+ CD4+ T cells. Those cells arrive in the BM before metastatic cells and set the pre-metastatic niche. In the absence of T cell derived RANKL, there is no pre-metastatic osteolytic disease and bone metastases do not take place. Recently, dendritic cells (DCs), the main T cell partner at the beginning of the immune response, came into the spotlight as a potential source of OCs progenitors under inflammatory conditions. Regarding bone metastasis, nothing is currently known about DCs plasticity or even its partnership with tumor induced T cells for BM pre-metastatic niche formation. Here, we show that splenic CD11c+ DCs stimulated with 4T1 conditioned media (CM) efficiently differentiated into mature and activated multinucleated giant cells (DC-OC) expressing TRAP and IL-23 cytokine. More important, 4T1 CM derived DC-OCs build a positive loop which amplifies the osteolytic phenomena by maintaining the RANKL+ Th17 T cells and by its own osteoclastic activity. In conclusion, our results indicate that differentiation of OCs from DCs may be achievable in the bone pre osteolytic disease context representing an alternative OC differentiation pathway. Besides being induced by high levels of T cells pro osteoclastogenic cytokines, especially by RANKL, DC-OC keep a positive feedback loop towards osteolysis, maintaining the pro-osteoclastogenic T cell phenotype in the BM.


Asunto(s)
Neoplasias Óseas , Neoplasias de la Mama , Diferenciación Celular , Células Dendríticas , Femenino , Humanos , Osteoclastos , Microambiente Tumoral
13.
Neoplasia ; 23(8): 823-834, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34246986

RESUMEN

Deregulation of miRNAs contributes to the development of distinct cancer types, including melanoma, an aggressive form of skin cancer characterized by high metastatic potential and poor prognosis. The expression of a set of 580 miRNAs was investigated in a model of murine melanoma progression, comprising non-metastatic (4C11-) and metastatic melanoma (4C11+) cells. A significant increase in miR-138-5p expression was found in the metastatic 4C11+ melanoma cells compared to 4C11-, which prompted us to investigate its role in melanoma aggressiveness. Functional assays, including anoikis resistance, colony formation, collective migration, serum-deprived growth capacity, as well as in vivo tumor growth and experimental metastasis were performed in 4C11- cells stably overexpressing miR-138-5p. miR-138-5p induced an aggressive phenotype in mouse melanoma cell lines leading to increased proliferation, migration and cell viability under stress conditions. Moreover, by overexpressing miR-138-5p, low-growing and non-metastatic 4C11- cells became highly proliferative and metastatic in vivo, similar to the metastatic 4C11+ cells. Luciferase reporter analysis identified the tumor suppressor Trp53 as a direct target of miR-138-5p. Using data sets from independent melanoma cohorts, miR-138-5p and P53 expression were also found deregulated in human melanoma samples, with their levels negatively and positively correlated with prognosis, respectively. Our data shows that the overexpression of miR-138-5p contributes to melanoma metastasis through the direct suppression of Trp53.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Melanoma/genética , Melanoma/mortalidad , MicroARNs/genética , Interferencia de ARN , Proteína p53 Supresora de Tumor/genética , Regiones no Traducidas 3' , Animales , Línea Celular Tumoral , Humanos , Melanoma/patología , Ratones , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , Análisis de Supervivencia
14.
PLoS Pathog ; 3(11): e185, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18052532

RESUMEN

Although the concept that dendritic cells (DCs) recognize pathogens through the engagement of Toll-like receptors is widely accepted, we recently suggested that immature DCs might sense kinin-releasing strains of Trypanosoma cruzi through the triggering of G-protein-coupled bradykinin B2 receptors (B2R). Here we report that C57BL/6.B2R-/- mice infected intraperitoneally with T. cruzi display higher parasitemia and mortality rates as compared to B2R+/+ mice. qRT-PCR revealed a 5-fold increase in T. cruzi DNA (14 d post-infection [p.i.]) in B2R-/- heart, while spleen parasitism was negligible in both mice strains. Analysis of recall responses (14 d p.i.) showed high and comparable frequencies of IFN-gamma-producing CD4+ and CD8+ T cells in the spleen of B2R-/- and wild-type mice. However, production of IFN-gamma by effector T cells isolated from B2R-/- heart was significantly reduced as compared with wild-type mice. As the infection continued, wild-type mice presented IFN-gamma-producing (CD4+CD44+ and CD8+CD44+) T cells both in the spleen and heart while B2R-/- mice showed negligible frequencies of such activated T cells. Furthermore, the collapse of type-1 immune responses in B2R-/- mice was linked to upregulated secretion of IL-17 and TNF-alpha by antigen-responsive CD4+ T cells. In vitro analysis of tissue culture trypomastigote interaction with splenic CD11c+ DCs indicated that DC maturation (IL-12, CD40, and CD86) is controlled by the kinin/B2R pathway. Further, systemic injection of trypomastigotes induced IL-12 production by CD11c+ DCs isolated from B2R+/+ spleen, but not by DCs from B2R-/- mice. Notably, adoptive transfer of B2R+/+ CD11c+ DCs (intravenously) into B2R-/- mice rendered them resistant to acute challenge, rescued development of type-1 immunity, and repressed TH17 responses. Collectively, our results demonstrate that activation of B2R, a DC sensor of endogenous maturation signals, is critically required for development of acquired resistance to T. cruzi infection.


Asunto(s)
Enfermedad de Chagas/inmunología , Células Dendríticas/inmunología , Cininas/metabolismo , Receptor de Bradiquinina B2/inmunología , Células TH1/inmunología , Traslado Adoptivo , Animales , Enfermedad de Chagas/metabolismo , Células Dendríticas/metabolismo , Citometría de Flujo , Interferón gamma/biosíntesis , Interleucina-12/biosíntesis , Interleucina-17/biosíntesis , Cininas/inmunología , Activación de Linfocitos/inmunología , Ratones , Ratones Mutantes , Reacción en Cadena de la Polimerasa , Receptor de Bradiquinina B2/metabolismo , Células TH1/metabolismo , Trypanosoma cruzi , Factor de Necrosis Tumoral alfa/biosíntesis
15.
Cancers (Basel) ; 11(9)2019 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-31514410

RESUMEN

p21cip1/waf1 is a central regulator of cell cycle control and survival. While mutations are rare, it is commonly dysregulated in several human cancers due to epigenetic mechanisms influencing its transcriptional control. These mechanisms include promoter hypermethylation as well as additional pathways such as histone acetylation or methylation. The epigenetic regulators include writers, such as DNA methyltransferases (DNMTs); histone acetyltransferases (HATs) and histone lysine methyltransferases; erasers, such as histone deacetylases (HDACs); histone lysine demethylases [e.g., the Lysine Demethylase (KDM) family]; DNA hydroxylases; readers, such as the methyl-CpG-binding proteins (MBPs); and bromodomain-containing proteins, including the bromo- and extraterminal domain (BET) family. We further discuss the roles that long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) play in the epigenetic control of p21cip1/waf1 expression and its function in human cancers.

16.
Mol Oncol ; 13(6): 1433-1449, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31069961

RESUMEN

The high mortality rate of melanoma is broadly associated with its metastatic potential. Tumor cell dissemination is strictly dependent on vascularization; therefore, angiogenesis and lymphangiogenesis play an essential role in metastasis. Hence, a better understanding of the players of tumor vascularization and establishing them as new molecular biomarkers might help to overcome the poor prognosis of melanoma patients. Here, we further characterized a linear murine model of melanoma progression and showed that the aggressiveness of melanoma cells is closely associated with high expression of angiogenic factors, such as Vegfc, Angpt2, and Six1, and that blockade of the vascular endothelial growth factor pathway by the inhibitor axitinib abrogates their tumorigenic potential in vitro and in the in vivo chicken chorioallantoic membrane assay. Furthermore, analysis of The Cancer Genome Atlas data revealed that the expression of the angiogenic factor ANGPT2 (P-value = 0.044) and the lymphangiogenic receptor VEGFR-3 (P-value = 0.002) were independent prognostic factors of overall survival in melanoma patients. Enhanced reduced representation bisulfite sequencing-based methylome profiling revealed for the first time a link between abnormal VEGFC, ANGPT2, and SIX1 gene expression and promoter hypomethylation in melanoma cells. In patients, VEGFC (P-value = 0.031), ANGPT2 (P-value < 0.001), and SIX1 (P-value = 0.009) promoter hypomethylation were independent prognostic factors of shorter overall survival. Hence, our data suggest that these angio- and lymphangiogenesis factors are potential biomarkers of melanoma prognosis. Moreover, these findings strongly support the applicability of our melanoma progression model to unravel new biomarkers for this aggressive human disease.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Linfangiogénesis/genética , Melanoma/genética , Regiones Promotoras Genéticas/genética , Animales , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Membrana Corioalantoides/metabolismo , Metilación de ADN/genética , Humanos , Metástasis Linfática/genética , Metástasis Linfática/patología , Melanoma/metabolismo , Melanoma/patología , Ratones , Neovascularización Patológica/genética , Pronóstico , Cicatrización de Heridas/fisiología
17.
Pest Manag Sci ; 64(7): 755-60, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18318460

RESUMEN

BACKGROUND: The activity of the major digestive cysteine proteinase detected in the intestinal tract of larvae of the bean weevil, Acanthoscelides obtectus (Say), was efficiently inhibited by the well-characterized cysteine proteinase synthetic inhibitor E-64 and also by a recombinant form of chagasin (r-chagasin), a tight-binding cysteine proteinase inhibitor protein from Trypanosoma cruzi. RESULTS: Incorporation of r-chagasin into an artificial diet system at 0.1 g kg(-1) retarded growth rate, decreased larval survival and led to complete mortality of A. obtectus at the end of the trial. The observed differences in growth rates occurred particularly in the first and second development stages. Artificial seeds containing high levels of r-chagasin (0.5-30 g kg(-1)) completely inhibited larval penetration. CONCLUSION: Together, the results reported in this paper support the hypothesis that the inhibitory activity of r-chagasin towards the major insect gut cysteine proteinase in vitro and in vivo is an accurate prediction of its insecticidal effects. The selectivity of this inhibitor against insect digestive proteinases supports the key role in parasite virulence by affecting the endogenous proteinase activity in its natural host.


Asunto(s)
Escarabajos/enzimología , Cisteína Endopeptidasas/metabolismo , Inhibidores de Cisteína Proteinasa/farmacología , Proteínas de Insectos/antagonistas & inhibidores , Control Biológico de Vectores , Proteínas Protozoarias/farmacología , Animales , Escarabajos/efectos de los fármacos , Escarabajos/fisiología , Inhibidores de Cisteína Proteinasa/genética , Inhibidores de Cisteína Proteinasa/metabolismo , Tracto Gastrointestinal/enzimología , Proteínas de Insectos/metabolismo , Larva/efectos de los fármacos , Larva/enzimología , Larva/fisiología , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacología
20.
Endocr Connect ; 7(5): 762-767, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29700098

RESUMEN

OBJECTIVES: Iodine deficiency during pregnancy is associated with obstetric and neonatal adverse outcomes. Serum thyroglobulin (sTg) and thyroid volume (TV) are optional tools to urinary iodine concentration (UIC) for defining iodine status. This cross-sectional study aims to evaluate the iodine status of pregnant women living in iodine-adequate area by spot UIC and correlation with sTg, TV and thyroid function. METHODS: Two hundred and seventy-three pregnant women were evaluated at three trimesters. All had no previous thyroid disease, no iodine supplementation and negative thyroperoxidase and thyroglobulin antibodies. Thyroid function and sTg were measured using electrochemiluminescence immunoassays. TV was determined by ultrasonography; UIC was determined using a modified Sandell-Kolthoff method. RESULTS: Median UIC was 146 µg/L, being 52% iodine deficient and only 4% excessive. TSH values were 1.50 ± 0.92, 1.50 ± 0.92 and 1.91 ± 0.96 mIU/L, respectively, in each trimester (P = 0.001). sTg did not change significantly during trimesters with median 11.2 ng/mL and only 3.3% had above 40 ng/mL. Mean TV was 9.3 ± 3.4 mL, which positively correlated with body mass index, but not with sTg. Only 4.5% presented with goitre.When pregnant women were categorized as iodine deficient (UIC < 150 µg/L), adequate (≥150 and <250 µg/L) and excessive (≥250 µg/L), sTg, thyroid hormones and TV at each trimester showed no statistical differences. CONCLUSIONS: Iodine deficiency was detected frequently in pregnant women living in iodine-adequate area. sTg concentration and TV did not correlate to UIC. Our observation also demonstrated that the Brazilian salt-iodization programme prevents deficiency, but does not maintain iodine status within adequate and recommended ranges for pregnant women.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA