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1.
Hum Mol Genet ; 33(5): 426-434, 2024 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-37956408

RESUMEN

BACKGROUND: Pathogenic germline variants in BRCA1-Associated Protein 1 (BAP1) cause BAP1 tumor predisposition syndrome (BAP1-TPDS). Carriers run especially a risk of uveal (UM) and cutaneous melanoma, malignant mesothelioma, and clear cell renal carcinoma. Approximately half of increasingly reported BAP1 variants lack accurate classification. Correct interpretation of pathogenicity can improve prognosis of the patients through tumor screening with better understanding of BAP1-TPDS. METHODS: We edited five rare BAP1 variants with differing functional characteristics identified from patients with UM in HAP1 cells using CRISPR-Cas9 and assayed their effect on cell adhesion/spreading (at 4 h) and proliferation (at 48 h), measured as cell index (CI), using xCELLigence real-time analysis system. RESULTS: In BAP1 knockout HAP1 cultures, cell number was half of wild type (WT) cultures at 48 h (p = 0.00021), reaching confluence later, and CI was 78% reduced (p < 0.0001). BAP1-TPDS-associated null variants c.67+1G>T and c.1780_1781insT, and a likely pathogenic missense variant c.281A>G reduced adhesion (all p ≤ 0.015) and proliferation by 74%-83% (all p ≤ 0.032). Another likely pathogenic missense variant c.680G>A reduced both by at least 50% (all p ≤ 0.032), whereas cells edited with likely benign one c.1526C>T grew similarly to WT. CONCLUSIONS: BAP1 is essential for optimal fitness of HAP1 cells. Pathogenic and likely pathogenic BAP1 variants reduced cell fitness, reflected in adhesion/spreading and proliferation properties. Further, moderate effects were quantifiable. Variant modelling in HAP1 with CRISPR-Cas9 enabled functional analysis of coding and non-coding region variants in an endogenous expression system.


Asunto(s)
Neoplasias Renales , Melanoma , Neoplasias Cutáneas , Neoplasias de la Úvea , Humanos , Melanoma/patología , Virulencia , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal/genética , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo , Proteínas Supresoras de Tumor/genética
2.
Nucleic Acids Res ; 48(9): 4725-4740, 2020 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-32313943

RESUMEN

Cellular stress causes multifaceted reactions to trigger adaptive responses to environmental cues at all levels of the gene expression pathway. RNA-binding proteins (RBP) are key contributors to stress-induced regulation of RNA fate and function. Here, we uncover the plasticity of the RNA interactome in stressed cells, differentiating between responses in the nucleus and in the cytoplasm. We applied enhanced RNA interactome capture (eRIC) analysis preceded by nucleo-cytoplasmic fractionation following arsenite-induced oxidative stress. The data reveal unexpectedly compartmentalized RNA interactomes and their responses to stress, including differential responses of RBPs in the nucleus versus the cytoplasm, which would have been missed by whole cell analyses.


Asunto(s)
Núcleo Celular/metabolismo , Citoplasma/metabolismo , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/metabolismo , Fraccionamiento Celular , Línea Celular Tumoral , Humanos , Estrés Oxidativo , Biosíntesis de Proteínas , Estabilidad del ARN
3.
Nucleic Acids Res ; 44(7): 3095-104, 2016 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-26681690

RESUMEN

As the formation of ribonucleoprotein complexes is a major mechanism of angiotensin II type 1 receptor (AT1R) regulation, we sought to identify novel AT1R mRNA binding proteins. By affinity purification and mass spectroscopy, we identified TIA-1. This interaction was confirmed by colocalization of AT1R mRNA and TIA-1 by FISH and immunofluorescence microscopy. In immunoprecipitates of endogenous TIA- 1, reverse transcription-PCR amplified AT1R mRNA. TIA-1 has two binding sites within AT1R 3'-UTR. The binding site proximal to the coding region is glyceraldehyde-3-phosphate dehydrogenase (GAPDH)-dependent whereas the distal binding site is not. TIA-1 functions as a part of endoplasmic reticulum (ER) stress response leading to stress granule (SG) formation and translational silencing. We and others have shown that AT1R expression is increased by ER stress-inducing factors. In unstressed cells, TIA-1 binds to AT1R mRNA and decreases AT1R protein expression. Fluorescence microscopy shows that ER stress induced by thapsigargin leads to the transfer of TIA-1 to SGs. In FISH analysis AT1R mRNA remains in the cytoplasm and no longer colocalizes with TIA-1. Thus, release of TIA-1-mediated suppression by ER stress increases AT1R protein expression. In conclusion, AT1R mRNA is regulated by TIA-1 in a ER stress-dependent manner.


Asunto(s)
Regiones no Traducidas 3' , Estrés del Retículo Endoplásmico , Regulación de la Expresión Génica , Proteínas de Unión a Poli(A)/metabolismo , Receptor de Angiotensina Tipo 1/genética , Sitios de Unión , Células Cultivadas , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Células HEK293 , Humanos , ARN Mensajero/metabolismo , Antígeno Intracelular 1 de las Células T
4.
Nucleic Acids Res ; 40(12): 5250-61, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22362742

RESUMEN

Angiotensin II type 1 receptor (AT1R) has a pathophysiological role in hypertension, atherosclerosis and heart failure. Type 2 diabetes is hyperinsulinemic state and a major risk factor for atherosclerosis and hypertension. It is known that hyperinsulinemia upregulates AT1R expression post-transcriptionally by increasing the half-life of AT1R mRNA, but little is known about the mechanism of this effect. In the present study, we first identified AT1R 3'-UTR as a mediator of insulin effect. Using 3'-UTR as a bait, we identified through analysis of insulin-stimulated cell lysates by affinity purification and mass spectrometry HuR as an insulin-regulated AT1R mRNA binding protein. By ribonucleoprotein immunoprecipitation, we found HuR binding to AT1R to be increased by insulin. Overexpression of HuR leads to increased AT1R expression in a 3'-UTR-dependent manner. Both insulin and HuR overexpression stabilize AT1R 3'-UTR and their responsive element within 3'-UTR are located within the same region. Cell fractionation demonstrated that insulin induced HuR translocation from nucleus to cytoplasm increased HuR binding to cytoplasmic AT1R 3'-UTR. Consistent with HuR translocation playing a mechanistic role in HuR effect, a reduction in the cytoplasmic levels of HuR either by silencing of HuR expression or by inhibition of HuR translocation into cytoplasm attenuated insulin response. These results show that HuR translocation to cytoplasm is enhanced by insulin leading to AT1R upregulation through HuR-mediated stabilization of AT1R mRNA.


Asunto(s)
Proteínas ELAV/metabolismo , Regulación de la Expresión Génica , Insulina/farmacología , Estabilidad del ARN , ARN Mensajero/metabolismo , Receptor de Angiotensina Tipo 1/genética , Regiones no Traducidas 3' , Sitios de Unión , Células Cultivadas , Ácidos Grasos Insaturados/farmacología , Células HEK293 , Humanos , Cinética , Transporte de Proteínas/efectos de los fármacos , Receptor de Angiotensina Tipo 1/metabolismo
5.
Acta Ophthalmol ; 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39435478

RESUMEN

PURPOSE: To describe clinical characteristics in Finnish patients with X-linked retinoschisis (XLRS) longitudinally with emphasis on retinal morphology and genotype-phenotype correlations. METHODS: A retrospective cohort study reviewed medical records from patients with genetically confirmed XLRS from the Department of Ophthalmology, Helsinki University Hospital. Best-corrected visual acuity (BCVA), refraction, colour fundus photography, spectral-domain optical coherence tomography and genetic information were collected. RESULTS: Fifty-two males were diagnosed at the median age of 7 years (range 1-57) and followed for a median of 8 years (range, 1-49). Baseline findings included macular retinoschisis in 92 (89%), macular atrophy in 25 (24%) and peripheral retinoschisis in 22 (21%) eyes. Vitreous haemorrhage occurred in 10 (10%) eyes, more frequently with peripheral schisis (p < 0.001). Nearly half of the patients, 22 (42%) were classified as visually impaired according to WHO. Median central retinal thickness was similar between initial (355 µm) and latest visits (360 µm) (p = 0.781). Low BCVA was associated with macular atrophy (p < 0.001), ellipsoid zone disruption (p = 0.007) and peripheral retinoschisis (p = 0.006). The three Finnish founder mutations c.214G >A, c.221G >T, and c.325G >C in exon 4 of retinoschisin 1 (RS1) were identified in 40 patients (77%). No associations were found between the genotypes and phenotypes. CONCLUSION: Three-fourths of the patients carried the Finnish founder mutations in RS1, but we did not detect any genotype-phenotype association. Macular atrophy was associated with the poorest visual acuity. Ocular compilations were associated with peripheral retinoschisis, suggesting that these patients should be followed more frequently.

6.
J Clin Microbiol ; 51(6): 1942-4, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23554204

RESUMEN

A carbapenem-resistant Alcaligenes faecalis strain was isolated from a surveillance swab of a service member injured in Afghanistan. The isolate was positive for bla(NDM) by real-time PCR. Species identification was reevaluated on three identification systems but was inconclusive. Genome sequencing indicated that the closest relative was Acinetobacter schindleri and that bla(NDM-1) was carried on a plasmid that shared >99% identity with one identified in an Acinetobacter lwoffii isolate. The isolate also carried a novel chromosomally encoded class D oxacillinase.


Asunto(s)
Acinetobacter/enzimología , Acinetobacter/genética , beta-Lactamasas/genética , Acinetobacter/aislamiento & purificación , Infecciones por Acinetobacter/microbiología , Afganistán , Cromosomas Bacterianos , ADN Bacteriano/química , ADN Bacteriano/genética , Humanos , Datos de Secuencia Molecular , Plásmidos , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN
7.
Acta Ophthalmol ; 101(7): 797-806, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37032519

RESUMEN

PURPOSE: To identify germline variants in myocilin (MYOC) and other known monogenic glaucoma genes in Finnish patients with juvenile open-angle glaucoma (JOAG). METHODS: Finnish patients with JOAG treated between 2010 and 2018 at the Department of Ophthalmology, Helsinki University Hospital, Finland, were enrolled. We sequenced all exonic regions and flanking splice sites of MYOC for five patients and one healthy relative using Sanger sequencing. In 48 patients, we performed exome sequencing to identify variants also in 28 other glaucoma-related genes. RESULTS: Fifty-three individuals with JOAG from 50 pedigrees, and one healthy relative, participated. The mean age at diagnosis was 30.8 years [SD 7.6; range 11 to 39]. Five probands had probably pathogenic variants in MYOC: c.1102C>T p.(Gln368Ter), c.1109C>T p.(Pro370Leu), c.1130C>T p.(Thr377Met), c.1132G>A p.(Asp378Asn) and c.1456C>T p.(Leu486Phe). Four of these patients had a family history of dominantly inherited JOAG. The frequency of MYOC variants was 10% (5 of 50 families). One patient and his mother with JOAG had a novel loss-of-function variant in the FOXC1 gene, c.366G>A p.(Trp122Ter). A patient with sporadic JOAG had a homozygous likely pathogenic variant in the LTBP2 gene, c.3938G>A p.(Cys1313Tyr). The genetic variants explained 14% (7 out of 50 families; 95% CI, 6%-23%) of JOAG in our cohort. CONCLUSIONS: The frequency of pathogenic variants in previously known glaucoma-associated genes is low in Finnish patients with JOAG. Because of the distinct genetic background of Finns, it might be possible to identify novel glaucoma genes through our JOAG series in the future.


Asunto(s)
Glaucoma de Ángulo Abierto , Glaucoma , Adulto , Humanos , Proteínas del Ojo/genética , Finlandia/epidemiología , Glaucoma/genética , Proteínas de Unión a TGF-beta Latente/genética , Mutación , Linaje
8.
Methods Mol Biol ; 2428: 291-304, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35171487

RESUMEN

RNA-binding proteins are key mediators of many of the RNA-regulatory functions throughout the RNA life cycle in the nucleus and in the cytoplasm. The invention and the recent refinement of the RNA-interactome capture technology has now enabled the analysis of the global RNA-interactome in living cells in the nucleus and in the cytoplasm separately. This technology thus allows an unprecedented differential view on the function of RNA-binding proteins in these compartments. Here we describe a method combining nucleo-cytoplasmic fractionation and enhanced RNA-interactome capture (eRIC) for studying RBPs binding to polyadenylated RNAs separately in the cytoplasmic and in the nuclear compartments.


Asunto(s)
Núcleo Celular , ARN , Núcleo Celular/metabolismo , Citoplasma/metabolismo , ARN/genética , ARN/metabolismo , ARN Mensajero/genética , Proteínas de Unión al ARN/metabolismo
9.
Br J Ophthalmol ; 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36385001

RESUMEN

AIMS: To elucidate the effect of NLRP3 variant c.61G>C on interleukin-1ß (IL-1ß) secretion in keratitis fugax hereditaria (KFH), a cryopyrin-associated periodic syndrome limited to the eye, and to probe the potential modifying role of prednisolone. METHODS: Peripheral blood mononuclear cells (PBMCs) isolated from whole blood of patients with KFH and healthy controls were grown under steady-state conditions or primed with lipopolysaccharide (LPS) with or without prednisolone, and subsequently activated with ATP. Cell lysates and proteins precipitated from the cell culture media were separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. NLRP3, procaspase-1, and IL-1ß were visualised by western blotting. The concentration of secreted IL-1ß in the culture media was quantified by ELISA. RESULTS: Following priming of the NLRP3 inflammasome with LPS, a lower threshold for IL-1ß secretion was observed in patient-derived PBMCs, compared with healthy controls (median, 124 vs 10 pg/mL, respectively). Interestingly, in PBMCs derived from patients with frequent KFH symptoms, LPS priming alone was able to trigger substantial IL-1ß secretion (median, 522 pg/mL), whereas those of patients experiencing occasional KFH attacks showed a subtler release of IL-1ß (median, 85 pg/mL). NLRP3 expression was significantly enhanced with LPS stimulation (p=0.03) whereas procaspase-1 expression was not affected. LPS and ATP treated PBMCs from patients with KFH showed significantly diminished IL-1ß secretion with prednisolone treatment (p=0.04). CONCLUSIONS: PBMCs from patients with KFH are more prone to secrete IL-1ß, confirming the presumption that the c.61G>C is a gain-of-function variant. Furthermore, prednisolone is confirmed as a potent drug to reduce IL-1ß secretion in KFH.

10.
Access Microbiol ; 4(12): acmi000410, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36644734

RESUMEN

Introduction: Haemophilus species are gram-negative, non-motile, facultative anaerobic coccobacilli in the larger family of Pasteurellaceae . Implicated in a variety of human diseases, Haemophilus species are also included in the 'HACEK' group of organisms, which are fastidious gram-negative bacteria, a well-described but uncommon cause of endocarditis. Among the Haemophilus species responsible for endocarditis, Haemophilus parainfluenzae is the most frequently isolated. However, novel species of Haemophilus have recently been described, and their clinical significance remains uncertain. Case presentation: A 35-year-old man was admitted to the hospital after presenting with a 3 month history of nightly fevers, night sweats and unintentional weight loss, with a new murmur detected on cardiac auscultation. Blood cultures returned positive for Haemophilus sputorum identified by matrix assisted laser desorption ionization - time of flight MS, and confirmed with whole genome sequencing. Echocardiography revealed the presence of an aortic valve vegetation, with aortic and mitral valve leaflet perforations. He was successfully treated with surgical bioprosthetic valve replacements and pathogen-directed antibiotics without complications. Conclusion: We describe a case of infective endocarditis due to H. sputorum , a newly identified Haemophilus species, which to the best of our knowledge has yet to be reported, and discuss the available literature regarding this organism.

11.
Genome Med ; 14(1): 147, 2022 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-36585742

RESUMEN

BACKGROUND: Extra-intestinal pathogenic Escherichia coli (ExPEC) are a leading cause of bloodstream and urinary tract infections worldwide. Over the last two decades, increased rates of antibiotic resistance in E. coli have been reported, further complicating treatment. Worryingly, specific lineages expressing extended-spectrum ß-lactamases (ESBLs) and fluoroquinolone resistance have proliferated and are now considered a serious threat. Obtaining contemporary information on the epidemiology and prevalence of these circulating lineages is critical for containing their spread globally and within the clinic. METHODS: Whole-genome sequencing (WGS), phylogenetic analysis, and antibiotic susceptibility testing were performed for a complete set of 2075 E. coli clinical isolates collected from 1776 patients at a large tertiary healthcare network in the USA between October 2019 and September 2020. RESULTS: The isolates represented two main phylogenetic groups, B2 and D, with six lineages accounting for 53% of strains: ST-69, ST-73, ST-95, ST-131, ST-127, and ST-1193. Twenty-seven percent of the primary isolates were multidrug resistant (MDR) and 5% carried an ESBL gene. Importantly, 74% of the ESBL-E.coli were co-resistant to fluoroquinolones and mostly belonged to pandemic ST-131 and emerging ST-1193. SNP-based detection of possible outbreaks identified 95 potential transmission clusters totaling 258 isolates (12% of the whole population) from ≥ 2 patients. While the proportion of MDR isolates was enriched in the set of putative transmission isolates compared to sporadic infections (35 vs 27%, p = 0.007), a large fraction (61%) of the predicted outbreaks (including the largest cluster grouping isolates from 12 patients) were caused by the transmission of non-MDR clones. CONCLUSION: By coupling in-depth genomic characterization with a complete sampling of clinical isolates for a full year, this study provides a rare and contemporary survey on the epidemiology and spread of E. coli in a large US healthcare network. While surveillance and infection control efforts often focus on ESBL and MDR lineages, our findings reveal that non-MDR isolates represent a large burden of infections, including those of predicted nosocomial origins. This increased awareness is key for implementing effective WGS-based surveillance as a routine technology for infection control.


Asunto(s)
Infección Hospitalaria , Infecciones por Escherichia coli , Humanos , Escherichia coli/genética , Infecciones por Escherichia coli/epidemiología , Infección Hospitalaria/epidemiología , Filogenia , beta-Lactamasas/genética , Genómica , Atención a la Salud , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética
12.
J Clin Microbiol ; 49(10): 3458-62, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21849695

RESUMEN

The Cepheid Xpert MTB/RIF research-use-only (RUO) assay and a laboratory-developed test (LDT) targeting IS6110 were evaluated and compared to mycobacterial culture as the gold standard. The performance characteristics of both molecular assays were determined by using 112 specimens from 90 patients, including 89 pulmonary specimens and 23 extrapulmonary specimens. Of the specimens tested, 37 (33%) were culture positive for the Mycobacterium tuberculosis complex; 29 were pulmonary, and 8 were extrapulmonary. Of these culture-positive specimens, 83% of the pulmonary specimens and 50% of the extrapulmonary specimens were smear positive. There was complete concordance between the smear-positive culture-positive specimens, independent of the anatomical site (100% sensitivity). The sensitivity of the MTB/RIF RUO assay for smear-negative specimens was 60% for pulmonary and 75% for extrapulmonary specimens, while the IS6110 LDT sensitivities were 40% and 0%, respectively. There was also complete concordance among the culture-negative specimens tested. Both assays showed 95% specificity, with four culture-negative specimens testing as positive. A review of patient records indicated that there was a high likelihood of the presence of M. tuberculosis complex DNA in the false-positive specimens. Biosafety analysis was performed and showed an acceptable reduction in organism viability using the processing methods described above. Both molecular assays are suitable for the detection of M. tuberculosis isolates in smear-positive pulmonary and extrapulmonary specimens, while the sensitivity of the detection of M. tuberculosis isolates in smear-negative specimens was variable.


Asunto(s)
Técnicas Bacteriológicas/métodos , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Tuberculosis/diagnóstico , Elementos Transponibles de ADN , ADN Bacteriano/genética , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/crecimiento & desarrollo , Sensibilidad y Especificidad , Tuberculosis/microbiología
13.
Nucleic Acids Res ; 37(7): 2346-58, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19246543

RESUMEN

Regulation of angiotensin II type 1 receptor (AT1R) has a pathophysiological role in hypertension, atherosclerosis and heart failure. We started from an observation that the 3'-untranslated region (3'-UTR) of AT1R mRNA suppressed AT1R translation. Using affinity purification for the separation of 3'-UTR-binding proteins and mass spectrometry for their identification, we describe glyceraldehyde 3-phosphate dehydrogenase (GAPDH) as an AT1R 3'-UTR-binding protein. RNA electrophoretic mobility shift analysis with purified GAPDH further demonstrated a direct interaction with the 3'-UTR while GAPDH immunoprecipitation confirmed this interaction with endogenous AT1R mRNA. GAPDH-binding site was mapped to 1-100 of 3'-UTR. GAPDH-bound target mRNAs were identified by expression array hybridization. Analysis of secondary structures shared among GAPDH targets led to the identification of a RNA motif rich in adenines and uracils. Silencing of GAPDH increased the expression of both endogenous and transfected AT1R. Similarly, a decrease in GAPDH expression by H(2)O(2) led to an increased level of AT1R expression. Consistent with GAPDH having a central role in H(2)O(2)-mediated AT1R regulation, both the deletion of GAPDH-binding site and GAPDH overexpression attenuated the effect of H(2)O(2) on AT1R mRNA. Taken together, GAPDH is a translational suppressor of AT1R and mediates the effect of H(2)O(2) on AT1R mRNA.


Asunto(s)
Regiones no Traducidas 3'/metabolismo , Regulación de la Expresión Génica , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Biosíntesis de Proteínas , Receptor de Angiotensina Tipo 1/genética , Secuencia de Bases , Línea Celular , Gliceraldehído-3-Fosfato Deshidrogenasas/antagonistas & inhibidores , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Humanos , Peróxido de Hidrógeno/farmacología , Datos de Secuencia Molecular , Interferencia de ARN , ARN Mensajero/química , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/metabolismo , Receptor de Angiotensina Tipo 1/metabolismo
14.
Prostaglandins Other Lipid Mediat ; 88(3-4): 73-81, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19010439

RESUMEN

Prostaglandin E(2) (PGE(2)) plays an important role in the normal physiology of many organ systems. Increased levels of this lipid mediator are associated with many disease states, and it potently regulates inflammatory responses. Three enzymes capable of in vitro synthesis of PGE(2) from the cyclooxygenase metabolite PGH(2) have been described. Here, we examine the contribution of one of these enzymes to PGE(2) production, mPges-2, which encodes microsomal prostaglandin synthase-2 (mPGES-2), by generating mice homozygous for the null allele of this gene. Loss of mPges-2 expression did not result in a measurable decrease in PGE(2) levels in any tissue or cell type examined from healthy mice. Taken together, analysis of the mPGES-2 deficient mouse lines does not substantiate the contention that mPGES-2 is a PGE(2) synthase.


Asunto(s)
Dinoprostona/biosíntesis , Oxidorreductasas Intramoleculares/fisiología , Animales , Northern Blotting , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/metabolismo , Interferón gamma/farmacología , Oxidorreductasas Intramoleculares/genética , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Proteínas de la Membrana/metabolismo , Ratones , Ratones Mutantes , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa , Prostaglandina-E Sintasas
15.
Cancer Res ; 66(13): 6649-56, 2006 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-16818638

RESUMEN

Prostaglandin E(2) (PGE(2)), a proinflammatory bioactive lipid, promotes cancer progression by modulating proliferation, apoptosis, and angiogenesis. PGE(2) is a downstream product of cyclooxygenase (COX) and is biochemically inactivated by prostaglandin dehydrogenase (PGDH). In the present study, we investigated the mechanisms by which PGDH is down-regulated in cancer. We show that epidermal growth factor (EGF) represses PGDH expression in colorectal cancer cells. EGF receptor (EGFR) signaling induces Snail, which binds conserved E-box elements in the PGDH promoter to repress transcription. Induction of PGE(2) catabolism through inhibition of EGFR signaling blocks cancer growth in vivo. In human colon cancers, elevated Snail expression correlates well with down-regulation of PGDH. These data indicate that PGDH may serve a tumor suppressor function in colorectal cancer and provide a possible COX-2-independent way to target PGE(2) to inhibit cancer progression.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Dinoprostona/metabolismo , Factor de Crecimiento Epidérmico/farmacología , Hidroxiprostaglandina Deshidrogenasas/biosíntesis , Factores de Transcripción/biosíntesis , Animales , Neoplasias Colorrectales/enzimología , Neoplasias Colorrectales/genética , Progresión de la Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Receptores ErbB/metabolismo , Células HCT116 , Células HT29 , Humanos , Hidroxiprostaglandina Deshidrogenasas/genética , Ratones , Ratones Endogámicos C57BL , Factores de Transcripción de la Familia Snail , Factores de Transcripción/genética , Transfección
16.
Methods Enzymol ; 407: 401-10, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16757341

RESUMEN

Oncogenic mutations in Ras (H-Ras, N-Ras, and K-Ras) are found in a wide variety of human malignancies, including adenocarcinomas of the colon, where K-Ras mutations often occur early in tumor development and strongly correlate with the transition to invasive adenocarcinoma. Our laboratory is interested in examining the interaction between Ras signaling and up-regulation of cyclooxygenase-2 (COX-2), a key regulator of prostaglandin biosynthesis. Our studies demonstrate that the Ras oncoprotein can regulate transcriptional activation and stabilization of COX-2 expression by several mechanisms. In this chapter we have outlined protocols and experimental approaches used in our laboratory to measure H-Ras up-regulation of COX-2 expression and to elaborate on more recent techniques that illustrate the importance of activation of Ras by prostaglandin E2 (PGE(2)). These methods have facilitated our understanding of the mechanisms by which the COX-2-derived PGE(2) and Ras activation of the mitogen-activated protein kinase (MAPK) signaling promotes oncogenic transformation. In light of the critical roles of both COX-2 and Ras signaling in carcinogenesis, our understanding of the complete signaling nuances between different isoforms of Ras on activation of COX-2, as well as understanding the novel mechanism whereby COX-2-derived PGE(2) constitutively activates Ras, will potentially aid in the identification of new targets for cancer therapy.


Asunto(s)
Ciclooxigenasa 2/metabolismo , Proteínas ras/fisiología , Animales , Línea Celular , Dinoprostona/fisiología , Activación Enzimática/efectos de los fármacos , Humanos , Sistema de Señalización de MAP Quinasas , Ratas , Regulación hacia Arriba
17.
Cancer Res ; 62(3): 901-9, 2002 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11830550

RESUMEN

Nuclear receptors are critical regulators of many physiological processes and have been shown to be involved in a variety of disease processes, including malignant neoplasms. Our laboratory is investigating the function of the retinoid-related orphan receptor gamma (RORgamma) and its possible role in disease. Studies of mice deficient in the expression of RORgamma demonstrated that this receptor plays a crucial role in the regulation of thymopoiesis and lymph node organogenesis. In this study, we show that changes in homeostasis in the thymus of RORgamma-/- mice are associated with a high incidence of T-cell lymphomas. Over 50% of the deficient mice of mixed genetic background die within the first 4 months as a result of thymic lymphomas. A high incidence of lymphomas was also observed in RORgamma-/- 129/SvEv mice. The lymphoblastic cells metastasized frequently to spleen and liver. No other tumor types were detected in any of RORgamma-/- mice that died during the course of the experiment, and none of the heterozygous mice developed thymic lymphomas. Lymphoma formation was associated with increased cellular proliferation and an increase in the number of apoptotic cells. When placed in culture, the RORgamma-/- lymphoblastic cells underwent accelerated "spontaneous" apoptosis at a rate similar to that of RORgamma-/- thymocytes. Upon prolonged culture, several lymphoblastic cell lines could be established. Analysis of the immunophenotype of the lymphoblastic cells showed that the CD4 and CD8 subpopulations varied substantially among different lymphomas. The established cell lines consisted mostly of CD44-CD25+CD4-CD8- cells. Our studies indicate that loss of RORgamma disturbs homeostasis in the thymus by enhancing apoptosis and cellular proliferation. The latter may enhance the probability of individual cells to acquire genetic alterations that make them escape negative selection and normal differentiation programs and as a consequence lead to increased susceptibility to the development of T-cell lymphoma.


Asunto(s)
Linfoma de Células T/metabolismo , Receptores Citoplasmáticos y Nucleares/fisiología , Receptores de Ácido Retinoico , Receptores de Hormona Tiroidea , Animales , Apoptosis/fisiología , División Celular/fisiología , Femenino , Inmunofenotipificación , Subgrupos Linfocitarios/patología , Subgrupos Linfocitarios/fisiología , Linfoma de Células T/etiología , Linfoma de Células T/inmunología , Linfoma de Células T/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/inmunología
18.
Mil Med ; 181(11): e1675-e1684, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27849507

RESUMEN

BACKGROUND: The U.S. Army 1st Area Medical Laboratory (1st AML) is currently the only deployable medical CBRNE (Chemical, Biological, Radiological, Nuclear, and Explosives) laboratory in the Army's Forces Command. In support of the United States Agency for International Development Ebola response, the U.S. military initiated Operation United Assistance (OUA), and deployed approximately 2,500 service members to support the Government of Liberia's Ebola control efforts. Due to its unique molecular diagnostic and expeditionary capabilities, the 1st AML was ordered to deploy in October of 2014 in support of OUA via establishment of Ebola testing laboratories. To meet the unique mission requirements of OUA, the unit was re-organized to operate in a split-based configuration and sustain four separate Ebola testing laboratories. METHODS: This article is a review of the 1st AML's OUA participation in a split-based configuration. Topics highlighted include pre-deployment planning/training, operational/logistical considerations in fielding/withdrawing laboratories, laboratory testing results, disease and non-battle injuries, and lessons learned. FINDINGS: Fielding the 1st AML in a split-based configuration required careful pre-deployment planning, additional training, optimal use of personnel, and the acquisition of additional laboratory equipment. Challenges in establishing and sustaining remote laboratories in Liberia included: difficulties in transportation of equipment due to poor road infrastructure, heavy equipment unloading, and equipment damage during transit. Between November 26, 2014 and February 18, 2015 the four 1st AML labs successfully tested blood samples from patients and oral swabs collected by burial teams in rural Liberia. The most significant equipment malfunction during laboratory operations was generators powering the labs, with the same problem impacting headquarters. Generator failures delayed laboratory operations/result reporting, and put temperature sensitive reagents at risk. None of the 22 1st AML soldiers (at remote labs or headquarters) had an Ebola exposure, none were infected with malaria or other tropical diseases, and none required evacuation from the time deployed to remote sites. The primary medical condition encountered was acute gastroenteritis, and within the first week of arrival to Liberia, 19 (86%) soldiers were affected. DISCUSSION/IMPACT/RECOMMENDATIONS: With proper planning and training, the 1st AML can successfully conduct split-based operations in an outbreak setting, and this capability can be utilized in future operations. The performance of the 1st AML during the current Ebola outbreak highlights the value of this asset, and the need to continue its evolution to support U.S. military operations.


Asunto(s)
Brotes de Enfermedades , Fiebre Hemorrágica Ebola/terapia , Unidades Hospitalarias/tendencias , Laboratorios/organización & administración , Fiebre Hemorrágica Ebola/diagnóstico , Humanos , Liberia , Personal Militar , Reacción en Cadena de la Polimerasa/métodos
19.
Expert Opin Ther Targets ; 13(6): 675-88, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19409031

RESUMEN

Multiple lines of evidence suggest that cyclooxygenase-2 (COX-2) upregulation is an early event in the development of non-small-cell lung cancer. Preclinical data indicate tumors with upregulation of COX-2 synthesize high levels of prostaglandin E2 (PGE2), which in turn are associated with increased production of proangiogenic factors and enhanced metastatic potential. These findings indicate that an increase in COX-2 expression may play a significant role in the development and growth of lung cancers and possibly with the acquisition of an invasive and metastatic phenotype. Consequently, inhibitors of COX-2 are being studied for their chemopreventative and therapeutic effects in individuals at high risk for lung cancer and patients with established cancers.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Inhibidores de la Ciclooxigenasa 2/uso terapéutico , Ciclooxigenasa 2/metabolismo , Eicosanoides/metabolismo , Neoplasias Pulmonares/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Ciclooxigenasa 2/genética , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Regulación hacia Arriba
20.
Cancer Res ; 68(15): 6468-76, 2008 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-18676872

RESUMEN

Although endocannabinoid signaling is important for certain aspects of gastrointestinal homeostasis, the role of the cannabinoid receptors (CB) in colorectal cancer has not been defined. Here we show that CB1 expression was silenced in human colorectal cancer due to methylation of the CB1 promoter. Our genetic and pharmacologic studies reveal that loss or inhibition of CB1 accelerated intestinal adenoma growth in Apc(Min/+) mice whereas activation of CB1 attenuated intestinal tumor growth by inducing cell death via down-regulation of the antiapoptotic factor survivin. This down-regulation of survivin by CB1 is mediated by a cyclic AMP-dependent protein kinase A signaling pathway. These results indicate that the endogenous cannabinoid system may represent a potential therapeutic target for prevention or treatment of colorectal cancer.


Asunto(s)
Neoplasias Intestinales/patología , Receptor Cannabinoide CB1/genética , Animales , Secuencia de Bases , Metilación de ADN , Cartilla de ADN , Regulación hacia Abajo , Genes Supresores de Tumor , Proteínas Inhibidoras de la Apoptosis , Neoplasias Intestinales/genética , Neoplasias Intestinales/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteínas Asociadas a Microtúbulos/genética , Regiones Promotoras Genéticas , ARN Mensajero/genética , Receptor Cannabinoide CB1/metabolismo , Proteínas Represoras , Transducción de Señal , Survivin
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