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1.
J Neurol Surg B Skull Base ; 84(5): 452-462, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37671294

RESUMEN

Background Epigenetics may predict treatment sensitivity and clinical course for patients with meningiomas more accurately than histopathology. Nonetheless, targeting epigenetic mechanisms is understudied for pharmacotherapeutic development for these tumors. The bio-molecular insights and potential therapeutic development of meningioma epigenetics led us to investigate epigenetic inhibition in meningiomas. Methods We screened a 43-tumor cohort using a 139-compound epigenetic inhibitor library to assess sensitivity of relevant meningioma subgroups to epigenetic inhibition. The cohort was composed of 5 cell lines and 38 tumors cultured directly from surgery; mean patient age was 56.6 years ± 13.9 standard deviation. Tumor categories: 38 primary tumors, 5 recurrent; 33 from females, 10 from males; 32 = grade 1; 10 = grade 2; 1 = grade 3. Results Consistent with our previous results, histone deacetylase inhibitors (HDACi) were the most efficacious class. Panobinostat significantly reduced cell viability in 36 of 43 tumors; 41 tumors had significant sensitivity to some HDACi. G9a inhibition and Jumonji-domain inhibition also significantly reduced cell viability across the cohort; tumors that lost sensitivity to panobinostat maintained sensitivity to either G9a or Jumonji-domain inhibition. Sensitivity to G9a and HDAC inhibition increased with tumor grade; tumor responses did not separate by gender. Few differences were found between recurrent and primary tumors, or between those with prior radiation versus those without. Conclusions Few efforts have investigated the efficacy of targeting epigenetic mechanisms to treat meningiomas, making the clinical utility of epigenetic inhibition largely unknown. Our results suggest that epigenetic inhibition is a targetable area for meningioma pharmacotherapy.

2.
JCI Insight ; 8(16)2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37606047

RESUMEN

We investigated the extent, biologic characterization, phenotypic specificity, and possible regulation of a ß1-adrenergic receptor-linked (ß1-AR-linked) gene signaling network (ß1-GSN) involved in left ventricular (LV) eccentric pathologic remodeling. A 430-member ß1-GSN was identified by mRNA expression in transgenic mice overexpressing human ß1-ARs or from literature curation, which exhibited opposite directional behavior in interventricular septum endomyocardial biopsies taken from patients with beta-blocker-treated, reverse remodeled dilated cardiomyopathies. With reverse remodeling, the major biologic categories and percentage of the dominant directional change were as follows: metabolic (19.3%, 81% upregulated); gene regulation (14.9%, 78% upregulated); extracellular matrix/fibrosis (9.1%, 92% downregulated); and cell homeostasis (13.3%, 60% upregulated). Regarding the comparison of ß1-GSN categories with expression from 19,243 nonnetwork genes, phenotypic selection for major ß1-GSN categories was exhibited for LV end systolic volume (contractility measure), ejection fraction (remodeling index), and pulmonary wedge pressure (wall tension surrogate), beginning at 3 months and persisting to study completion at 12 months. In addition, 121 lncRNAs were identified as possibly involved in cis-acting regulation of ß1-GSN members. We conclude that an extensive 430-member gene network downstream from the ß1-AR is involved in pathologic ventricular remodeling, with metabolic genes as the most prevalent category.


Asunto(s)
Productos Biológicos , Cardiomiopatía Dilatada , Animales , Ratones , Humanos , Cardiomiopatía Dilatada/genética , Redes Reguladoras de Genes , Transducción de Señal , Ratones Transgénicos , Receptores Adrenérgicos
3.
bioRxiv ; 2023 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-37214911

RESUMEN

Cells require the ability to adapt to changing environmental conditions, however, it is unclear how these changes elicit stable permanent changes in genomes. We demonstrate that, in response to environmental metal exposure, the metallothionein (MT) locus undergoes DNA rereplication generating transient site-specific gene amplifications (TSSGs). Chronic metal exposure allows transition from MT TSSG to inherited MT gene amplification through homologous recombination within and outside of the MT locus. DNA rereplication of the MT locus is suppressed by H3K27me3 and EZH2. Long-term ablation of EZH2 activity eventually leads to integration and inheritance of MT gene amplifications without the selective pressure of metal exposure. The rereplication and inheritance of MT gene amplification is an evolutionarily conserved response to environmental metal from yeast to human. Our results describe a new paradigm for adaptation to environmental stress where targeted, transient DNA rereplication precedes stable inherited gene amplification.

4.
Cancers (Basel) ; 14(9)2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35565439

RESUMEN

Extrachromosomal circular DNA has emerged as a frequent genomic alteration in tumors. High numbers of circular DNAs correspond to poor prognosis suggesting an important function in tumor biology. However, despite mounting evidence supporting the importance of circular DNA, little is known about their production, maintenance, or selection. To provide insight into these processes, we analyzed circular DNA elements computationally identified in 355 TCGA tumors spanning 22 tumor types. Circular DNAs originated from common genomic loci irrespective of cancer type. Genes found in circularized genomic regions were more likely to be expressed and were enriched in cancer-related pathways. Finally, in support of a model for circle generation through either a homology or microhomology-mediated process, circles exhibit homology near their breakpoint. These breakpoints are also enriched in specific DNA motifs. Our analysis supports a model where gene-containing circles emerge from common, highly transcribed regions through a homology-mediated process.

5.
World Neurosurg ; 162: e99-e119, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35248772

RESUMEN

OBJECTIVE: Meningiomas are a common primary central nervous system tumor that lack a U.S. Food and Drug Administration-approved pharmacotherapy. Approximately 20%-35% of meningiomas are classified as higher grade with poor outcome, whereas patients with lower-grade meningiomas are known to have long-term neurologic deficits and reduced overall survival. Recent efforts to understand the epigenetic landscape of meningiomas have highlighted the importance of DNA methylation for predicting tumor outcomes and prognosis; therefore, inhibition of these pathways may present a viable therapy for these tumors. METHODS: In this study, we perform dose-response curves of decitabine, a DNA methyltransferase inhibitor, on patient-cultured tumors and meningioma cell lines. RESULTS: Thirty total samples were evaluated, including 24 patient-cultured tumors and 6 established meningioma cell lines. Meningiomas were found to have a significant reduction in cell viability after decitabine treatment in a dose dependent manner. The effect was primarily driven by 11 of the 30 tumors in our cohort, or 36.7%. Decitabine significantly reduced cell viability across all grades, tumors from different sexes, recurrent and primary tumors, as well as tumors without a history of previous radiation. Surprisingly, our single radiation-induced tumor did demonstrate greater viability after decitabine treatment. CONCLUSIONS: Our work has identified a potential drug candidate in decitabine for the treatment of meningiomas regardless of clinical subgroup. These data require further evaluation in preclinical models, and the conclusions based on clinical subgroups need to be evaluated in a larger cohort to achieve appropriate statistical power.


Asunto(s)
Neoplasias Meníngeas , Meningioma , ADN , Metilación de ADN , Decitabina , Humanos , Neoplasias Meníngeas/tratamiento farmacológico , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/patología , Meningioma/tratamiento farmacológico , Meningioma/genética , Meningioma/patología , Transferasas
6.
J Am Coll Cardiol ; 78(18): 1782-1795, 2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34711337

RESUMEN

BACKGROUND: The effects of nonphysiological flow generated by continuous-flow (CF) left ventricular assist devices (LVADs) on the aorta remain poorly understood. OBJECTIVES: The authors sought to quantify indexes of fibrosis and determine the molecular signature of post-CF-LVAD vascular remodeling. METHODS: Paired aortic tissue was collected at CF-LVAD implant and subsequently at transplant from 22 patients. Aortic wall morphometry and fibrillar collagen content (a measure of fibrosis) was quantified. In addition, whole-transcriptome profiling by RNA sequencing and follow-up immunohistochemistry were performed to evaluate CF-LVAD-mediated changes in aortic mRNA and protein expression. RESULTS: The mean age was 52 ± 12 years, with a mean duration of CF-LVAD of 224 ± 193 days (range 45-798 days). There was a significant increase in the thickness of the collagen-rich adventitial layer from 218 ± 110 µm pre-LVAD to 410 ± 209 µm post-LVAD (P < 0.01). Furthermore, there was an increase in intimal and medial mean fibrillar collagen intensity from 22 ± 11 a.u. pre-LVAD to 41 ± 24 a.u. post-LVAD (P < 0.0001). The magnitude of this increase in fibrosis was greater among patients with longer durations of CF-LVAD support. CF-LVAD led to profound down-regulation in expression of extracellular matrix-degrading enzymes, such as matrix metalloproteinase-19 and ADAMTS4, whereas no evidence of fibroblast activation was noted. CONCLUSIONS: There is aortic remodeling and fibrosis after CF-LVAD that correlates with the duration of support. This fibrosis is due, at least in part, to suppression of extracellular matrix-degrading enzyme expression. Further research is needed to examine the contribution of nonphysiological flow patterns on vascular function and whether modulation of pulsatility may improve vascular remodeling and long-term outcomes.


Asunto(s)
Enfermedades de la Aorta , Circulación Asistida , Matriz Extracelular/enzimología , Insuficiencia Cardíaca/terapia , Corazón Auxiliar/efectos adversos , Proteína ADAMTS4/metabolismo , Enfermedades de la Aorta/etiología , Enfermedades de la Aorta/patología , Enfermedades de la Aorta/fisiopatología , Circulación Asistida/efectos adversos , Circulación Asistida/instrumentación , Circulación Asistida/métodos , Femenino , Fibrosis , Humanos , Inmunohistoquímica , Efectos Adversos a Largo Plazo/patología , Masculino , Metaloproteinasas de la Matriz Secretadas/metabolismo , Persona de Mediana Edad , Análisis de Secuencia de ARN/métodos , Remodelación Vascular/fisiología
7.
Int J Mol Sci ; 22(15)2021 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-34360613

RESUMEN

BACKGROUND: A major contributor to disability after hemorrhagic stroke is secondary brain damage induced by the inflammatory response. Following stroke, global increases in numerous cytokines-many associated with worse outcomes-occur within the brain, cerebrospinal fluid, and peripheral blood. Extracellular vesicles (EVs) may traffic inflammatory cytokines from damaged tissue within the brain, as well as peripheral sources, across the blood-brain barrier, and they may be a critical component of post-stroke neuroinflammatory signaling. METHODS: We performed a comprehensive analysis of cytokine concentrations bound to plasma EV surfaces and/or sequestered within the vesicles themselves. These concentrations were correlated to patient acute neurological condition by the Glasgow Coma Scale (GCS) and to chronic, long-term outcome via the Glasgow Outcome Scale-Extended (GOS-E). RESULTS: Pro-inflammatory cytokines detected from plasma EVs were correlated to worse outcomes in hemorrhagic stroke patients. Anti-inflammatory cytokines detected within EVs were still correlated to poor outcomes despite their putative neuroprotective properties. Inflammatory cytokines macrophage-derived chemokine (MDC/CCL2), colony stimulating factor 1 (CSF1), interleukin 7 (IL7), and monokine induced by gamma interferon (MIG/CXCL9) were significantly correlated to both negative GCS and GOS-E when bound to plasma EV membranes. CONCLUSIONS: These findings correlate plasma-derived EV cytokine content with detrimental outcomes after stroke, highlighting the potential for EVs to provide cytokines with a means of long-range delivery of inflammatory signals that perpetuate neuroinflammation after stroke, thus hindering recovery.


Asunto(s)
Lesiones Encefálicas/diagnóstico , Citocinas/sangre , Vesículas Extracelulares/metabolismo , Accidente Cerebrovascular/complicaciones , Lesiones Encefálicas/sangre , Lesiones Encefálicas/etiología , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
8.
J Clin Neurosci ; 91: 105-109, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34373013

RESUMEN

Emerging evidence suggest WHO grade III meningiomas that arise de novo as opposed to dedifferentiating from a lower grade may harbor differing prognoses. To investigate this, a single institution retrospective analysis of prospectively acquired patients between 1999 and 2018 was performed. Clinical data and radiographic parameters were reviewed to calculate progression free survival and overall survival in patients undergoing microsurgical resection. Next generation targeted sequencing of meningioma associated genes was performed on 11 tumors. Eighteen patients were identified as undergoing surgical resection of WHO grade III meningioma. Nine patients (50%) had de novo arising tumors and nine patients had secondary progressive tumors. To compare outcomes, only those patients undergoing gross total resection (Simpson grade I) were included for survival analysis. There was an improvement in median progression free survival for de novo resected tumors as compared to secondary progressive tumors (p = 0.02). Median overall survival for patients with de novo tumors was not statistically improved compared to that of secondary progressive tumors (p = 0.22). Next generation sequencing of targeted genes (NF2, BAP1, TRAF7, KLF4, SMO and AKT) revealed 5/11 tumors containing mutations in the NF2 gene, 2/11 containing BAP1 mutations, and a single tumor containing mutations in both NF2 and TRAF7. More mutations in NF2 and BAP1 were seen in the secondary progressive tumors. In conclusion, patients undergoing gross total resection for de novo arising grade III meningiomas showed improved progression free survival, though similar overall survival, as compared to those patients with secondary progressive tumors. Further studies focused on tumor associated genes and other associated risk factors are needed to improve risk-stratification.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Humanos , Factor 4 Similar a Kruppel , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/cirugía , Meningioma/diagnóstico por imagen , Meningioma/genética , Meningioma/cirugía , Supervivencia sin Progresión , Estudios Retrospectivos , Proteínas Supresoras de Tumor , Ubiquitina Tiolesterasa , Organización Mundial de la Salud
9.
J Clin Med ; 10(14)2021 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-34300316

RESUMEN

BACKGROUND: Meningiomas are the most common primary central nervous system tumors. 20-30% of these tumors are considered high-grade and associated with poor prognosis and high recurrence rates. Despite the high occurrence of meningiomas, there are no FDA-approved compounds for the treatment of these tumors. METHODS: In this study, we screened patient-cultured meningiomas with an epigenetic compound library to identify targetable mechanisms for the potential treatment of these tumors. Meningioma cell cultures were generated directly from surgically resected patient tumors and were cultured on a neural matrix. Cells were treated with a library of compounds meant to target epigenetic functions. RESULTS: Although each tumor displayed a unique compound sensitivity profile, Panobinostat, LAQ824, and HC toxin were broadly effective across most tumors. These three compounds are broad-spectrum Histone Deacetylase (HDAC) inhibitors which target class I, IIa, and IIb HDACs. Panobinostat was identified as the most broadly effective compound, capable of significantly decreasing the average cell viability of the sample cohort, regardless of tumor grade, recurrence, radiation, and patient gender. CONCLUSIONS: These findings strongly suggest an important role of HDACs in meningioma biology and as a targetable mechanism. Additional validation studies are necessary to confirm these promising findings, as well to identify an ideal HDAC inhibitor candidate to develop for clinical use.

10.
Pancreas ; 50(3): 378-385, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33835969

RESUMEN

OBJECTIVES: Data regarding the safety of endoscopic retrograde pancreatography (ERP) are limited compared with biliary endoscopic retrograde cholangiopancreatography. The aim of this study was to determine adverse events (AEs) associated with therapeutic ERP. METHODS: This single-center retrospective study examined consecutive therapeutic ERPs with the primary intention of cannulating the pancreatic duct. Multivariate logistic regression was performed to identify risk factors for AEs. RESULTS: A total of 3023 ERPs were performed in 1288 patients (mean age, 50.3 years; 57.8% female) from January 2000 to January 2017. Overall AE rate was 18.9% with abdominal pain requiring admission (9.8%) and post-ERP pancreatitis (5.7%) being most common. On multivariate analysis, female sex (adjusted odds ratio [aOR], 2.3; 95% confidence interval [CI], 1.9-2.9), acute recurrent pancreatitis (aOR, 5.0; 95% CI, 1.7-15.3), chronic pancreatitis (aOR, 1.8; 95% CI, 1.3-2.6), and pancreatic sphincter of Oddi dysfunction (aOR, 2.1; 95% CI, 1.4-3.3) were associated with an increased risk of overall AEs. Pancreatic sphincterotomy (aOR, 1.9; 95% CI, 1.5-2.4) and therapeutic stenting (aOR, 1.6; 95% CI, 1.2-2.2) also increased the risk of AEs. CONCLUSIONS: Nearly 1 in 5 patients who undergo therapeutic ERP will experience an AE; however, the rates of major AEs, including post-ERP pancreatitis, bleeding, and perforation, are low.


Asunto(s)
Endoscopía del Sistema Digestivo/efectos adversos , Páncreas/cirugía , Pancreatectomía/efectos adversos , Conductos Pancreáticos/cirugía , Complicaciones Posoperatorias/etiología , Adulto , Anciano , Endoscopía del Sistema Digestivo/métodos , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pancreatectomía/métodos , Pancreatitis/diagnóstico , Pancreatitis/etiología , Complicaciones Posoperatorias/diagnóstico , Estudios Retrospectivos , Factores de Riesgo
11.
Dig Dis Sci ; 66(4): 1276-1284, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32430658

RESUMEN

BACKGROUND: Biliary stricture evaluation with brush cytology and intraductal forceps biopsy carries a low sensitivity, but the combination of newer modalities may improve sensitivity. AIM: To determine whether the addition of advanced modalities increases diagnostic yield of ERCP-based sampling. METHODS: This single-center retrospective study evaluates patients with biliary strictures sampled using brush cytology. Operating characteristics were calculated for individual and combinations of modalities including cholangioscopy, fluoroscopy- and cholangioscopy-directed intraductal biopsy, fluorescence in situ hybridization (FISH), and confocal laser endomicroscopy. Analyses under Standard Criteria (SC) included malignant results as "positive" and Expanded Criteria (EC) included "suspicious" and "high-grade dysplasia" results as "positive." RESULTS: A total of 614 patients were included, and 354 (57.8%) received brush cytology alone, which had a sensitivity of 38.5% (SC) to 40.3% (EC) and a specificity of 97.8% (EC) to 99.3% (SC). Combining brush cytology with fluoroscopy-guided biopsy (n = 259, 42.2%) had a sensitivity of 62.5% (SC) to 67.9% (EC) and specificity of 90.2% (EC) to 96.7% (SC). Adding FISH to brush cytology had a sensitivity of 84.2% (SC) to 87.5% (EC) and specificity of 54.1% (SC and EC), while cholangioscopy visualization addition resulted in a sensitivity of 80.4% (SC) to 92.2% (EC) and specificity of 67.3% (EC) to 89.1% (SC). There were no significant differences in sensitivity and specificity using SC and EC. CONCLUSIONS: Brush cytology has a low sensitivity, but the addition of other modalities increases sensitivity. There was no difference in specificity between the SC and the EC, supporting the inclusion of "suspicious" impressions with malignant results at our center.


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica/métodos , Colestasis/diagnóstico por imagen , Colestasis/patología , Citodiagnóstico/métodos , Hibridación Fluorescente in Situ/métodos , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Adulto , Anciano , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/cirugía , Colestasis/cirugía , Constricción Patológica/diagnóstico por imagen , Constricción Patológica/patología , Femenino , Humanos , Masculino , Microscopía Confocal/métodos , Persona de Mediana Edad , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Estudios Retrospectivos
12.
Nucleic Acids Res ; 48(10): e58, 2020 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-32239215

RESUMEN

Changes in gene copy number contribute to genomic instability, the onset and progression of cancer, developmental abnormalities and adaptive potential. The origins of gene amplifications have remained elusive; however, DNA rereplication has been implicated as a source of gene amplifications. The inability to determine which sequences are rereplicated and under what conditions have made it difficult to determine the validity of the proposed models. Here we present Rerep-Seq, a technique that selectively enriches for rereplicated DNA in preparation for analysis by DNA sequencing that can be applied to any species. We validated Rerep-Seq by simulating DNA rereplication in yeast and human cells. Using Rerep-Seq, we demonstrate that rereplication induced in Saccharomyces cerevisiae by deregulated origin licensing is non-random and defined by broad domains that span multiple replication origins and topological boundaries.


Asunto(s)
Replicación del ADN , Análisis de Secuencia de ADN/métodos , Línea Celular , Humanos , Saccharomyces cerevisiae/genética
13.
PLoS One ; 14(8): e0220573, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31374110

RESUMEN

RATIONALE: In virtually all models of heart failure, prognosis is determined by right ventricular (RV) function; thus, understanding the cellular mechanisms contributing to RV dysfunction is critical. Whole organ remodeling is associated with cell-specific changes, including cardiomyocyte dedifferentiation and activation of cardiac fibroblasts (Cfib) which in turn is linked to disorganization of cytoskeletal proteins and loss of sarcomeric structures. However, how these cellular changes contribute to RV function remains unknown. We've previously shown significant organ-level RV dysfunction in a large animal model of pulmonary hypertension (PH) which was not mirrored by reduced function of isolated cardiomyocytes. We hypothesized that factors produced by the endogenous Cfib contribute to global RV dysfunction by generating a heterogeneous cellular environment populated by dedifferentiated cells. OBJECTIVE: To determine the effect of Cfib conditioned media (CM) from the PH calf (PH-CM) on adult rat ventricular myocytes (ARVM) in culture. METHODS AND RESULTS: Brief exposure (<2 days) to PH-CM results in rapid, marked dedifferentiation of ARVM to a neonatal-like phenotype exhibiting spontaneous contractile behavior. Dedifferentiated cells maintain viability for over 30 days with continued expression of cardiomyocyte proteins including TnI and α-actinin yet exhibit myofibroblast characteristics including expression of α-smooth muscle actin. Using a bioinformatics approach to identify factor(s) that contribute to dedifferentiation, we found activation of the PH Cfib results in a unique transcriptome correlating with factors both in the secretome and with activated pathways in the dedifferentiated myocyte. Further, we identified upregulation of periostin in the Cfib and CM, and demonstrate that periostin is sufficient to drive cardiomyocyte dedifferentiation. CONCLUSIONS: These data suggest that paracrine factor(s) released by Cfib from the PH calf signal a phenotypic transformation in a population of cardiomyocytes that likely contributes to RV dysfunction. Therapies targeting this process, such as inhibition of periostin, have the potential to prevent RV dysfunction.


Asunto(s)
Desdiferenciación Celular/fisiología , Fibroblastos/metabolismo , Ventrículos Cardíacos/metabolismo , Hipertensión Pulmonar/metabolismo , Miocitos Cardíacos/citología , Disfunción Ventricular Derecha/metabolismo , Animales , Bovinos , Modelos Animales de Enfermedad , Fibroblastos/citología , Ventrículos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Función Ventricular Derecha/fisiología , Remodelación Ventricular
14.
J Biol Chem ; 294(21): 8640-8652, 2019 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-30962285

RESUMEN

Histone deacetylase 5 (HDAC5) and HDAC9 are class IIa HDACs that function as signal-responsive repressors of the epigenetic program for pathological cardiomyocyte hypertrophy. The conserved deacetylase domains of HDAC5 and HDAC9 are not required for inhibition of cardiac hypertrophy. Thus, the biological function of class IIa HDAC catalytic activity in the heart remains unknown. Here we demonstrate that catalytic activity of HDAC5, but not HDAC9, suppresses mitochondrial reactive oxygen species generation and subsequent induction of NF-E2-related factor 2 (NRF2)-dependent antioxidant gene expression in cardiomyocytes. Treatment of cardiomyocytes with TMP195 or TMP269, which are selective class IIa HDAC inhibitors, or shRNA-mediated knockdown of HDAC5 but not HDAC9 leads to stimulation of NRF2-mediated transcription in a reactive oxygen species-dependent manner. Conversely, ectopic expression of catalytically active HDAC5 decreases cardiomyocyte oxidative stress and represses NRF2 activation. These findings establish a role of the catalytic domain of HDAC5 in the control of cardiomyocyte redox homeostasis and define TMP195 and TMP269 as a novel class of NRF2 activators that function by suppressing the enzymatic activity of an epigenetic regulator.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Histona Desacetilasas/biosíntesis , Miocitos Cardíacos/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Animales , Benzamidas/farmacología , Células HEK293 , Histona Desacetilasas/genética , Humanos , Mitocondrias Cardíacas/genética , Mitocondrias Cardíacas/metabolismo , Miocitos Cardíacos/citología , Factor 2 Relacionado con NF-E2/genética , Oxadiazoles/farmacología , Dominios Proteicos , Ratas , Especies Reactivas de Oxígeno/metabolismo , Proteínas Represoras/biosíntesis , Proteínas Represoras/genética
15.
Am J Hum Genet ; 104(5): 968-976, 2019 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-31031011

RESUMEN

The role of somatic genetic variants in the pathogenesis of intracranial-aneurysm formation is unknown. We identified a 23-year-old man with progressive, right-sided intracranial aneurysms, ipsilateral to an impressive cutaneous phenotype. The index individual underwent a series of genetic evaluations for known connective-tissue disorders, but the evaluations were unrevealing. Paired-sample exome sequencing between blood and fibroblasts derived from the diseased areas detected a single novel variant predicted to cause a p.Tyr562Cys (g.149505130T>C [GRCh37/hg19]; c.1685A>G) change within the platelet-derived growth factor receptor ß gene (PDGFRB), a juxtamembrane-coding region. Variant-allele fractions ranged from 18.75% to 53.33% within histologically abnormal tissue, suggesting post-zygotic or somatic mosaicism. In an independent cohort of aneurysm specimens, we detected somatic-activating PDGFRB variants in the juxtamembrane domain or the kinase activation loop in 4/6 fusiform aneurysms (and 0/38 saccular aneurysms; Fisher's exact test, p < 0.001). PDGFRB-variant, but not wild-type, patient cells were found to have overactive auto-phosphorylation with downstream activation of ERK, SRC, and AKT. The expression of discovered variants demonstrated non-ligand-dependent auto-phosphorylation, responsive to the kinase inhibitor sunitinib. Somatic gain-of-function variants in PDGFRB are a novel mechanism in the pathophysiology of fusiform cerebral aneurysms and suggest a potential role for targeted therapy with kinase inhibitors.


Asunto(s)
Aneurisma/genética , Aneurisma Intracraneal/genética , Mutación , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Adolescente , Adulto , Secuencia de Aminoácidos , Aneurisma/patología , Niño , Estudios de Cohortes , Femenino , Humanos , Aneurisma Intracraneal/patología , Masculino , Homología de Secuencia , Adulto Joven
16.
Int J Nanomedicine ; 13: 7217-7227, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30510414

RESUMEN

BACKGROUND: Tendon-derived stem cells (TDSCs) are key factors associated with regeneration and healing in tendinopathy. The aim of this study was to investigate the effects of mechanical stiffness and topographic signals on the differentiation of TDSCs depending on age and pathological conditions. MATERIALS AND METHODS: We compared TDSCs extracted from normal tendon tissues with TDSCs from tendinopathic Achilles tendon tissues of Sprague Dawley rats in vitro and TDSCs cultured on nanotopographic cues and substrate stiffness to determine how to control the TDSCs. The tendinopathy model was created using a chemical induction method, and the tendon injury model was created via an injury-and-overuse method. Norland Optical Adhesive 86 (NOA86) substrate with 2.48 GPa stiffness with and without 800 nm-wide nanogrooves and a polyurethane substrate with 800 nm-wide nanogrooves were used. RESULTS: TDSCs from 5-week-old normal tendon showed high expression of type III collagen on the flat NOA86 substrate. In the 15-week normal tendon model, expression of type III collagen was high in TDSCs cultured on the 800 nm NOA86 substrates. However, in the 15-week tendon injury model, expression of type III collagen was similar irrespective of nanotopographic cues or substrate stiffness. The expression of type I collagen was also independent of nanotopographic cues and substrate stiffness in the 15-week normal and tendon injury models. Gene expression of scleraxis was increased in TDSCs cultured on the flat NOA86 substrate in the 5-week normal tendon model (P=0.001). In the 15-week normal tendon model, scleraxis was highly expressed in TDSCs cultured on the 800 nm and flat NOA86 substrate (P=0.043). However, this gene expression was not significantly different between the substrates in the 5-week tendinopathy and 15-week tendon injury models. CONCLUSION: Development and maturation of tendon are enhanced when TDSCs from normal tendons were cultured on stiff surface, but not when the TDSCs came from pathologic models. Therapeutic applications of TDSCs need to be flexible based on tendon age and tendinopathy.


Asunto(s)
Tendón Calcáneo/patología , Nanopartículas/química , Células Madre/citología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Fenómenos Biomecánicos , Diferenciación Celular/efectos de los fármacos , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Señales (Psicología) , Regulación de la Expresión Génica , Masculino , Ratas , Ratas Sprague-Dawley , Traumatismos de los Tendones/genética , Traumatismos de los Tendones/patología , Cicatrización de Heridas
17.
Scand J Gastroenterol ; 53(10-11): 1358-1363, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30394137

RESUMEN

OBJECTIVES: Evaluation of indeterminate biliary strictures remains challenging due to limited sensitivity of endoscopic tissue sampling. Biliary probe-based confocal laser endomicroscopy (pCLE) has shown promise to detect and exclude neoplasia. However, knowledge of whether individual inflammatory criteria are more prevalent in neoplasia compared to benign strictures is limited. The objective of this work is to improve diagnosis of neoplastic and inflammatory conditions using pCLE. MATERIALS AND METHODS: The charts of all patients who underwent pCLE at a single referral center between 2009 and 2015 were reviewed. ERCP reports were reviewed for eleven Miami and Paris criteria. Primary outcome was the identification of neoplasia by histopathology (defined as high-grade dysplasia and/or adenocarcinoma). To model predictors of neoplasia, we fit a binary regression model incorporating data from pCLE operating criteria, pCLE impression, and PSC status. RESULTS: 97 patients were identified. In the 27 patients with neoplasia, there was increasing number of Miami malignant criteria (Pearson r = 0.512, p < .001) while inflammatory criteria were less prevalent. 10% (5/51, p < .001) of patients with benign pCLE impression developed neoplasia, while 48% (22/46, p < .001) with suspicious pCLE impressions developed neoplasia. The binary regression model to predict neoplasia had a sensitivity of 83.3%, specificity of 92.5%, and overall accuracy 89.7%. CONCLUSIONS: Presence of malignant criteria and absence of certain inflammatory criteria are more prevalent in patients with neoplasia. Our model, which weights individual imaging components, shows impressive sensitivity and specificity over prior prognostic efforts. Prospective studies will be required to evaluate this model.


Asunto(s)
Neoplasias de los Conductos Biliares/diagnóstico , Conductos Biliares Intrahepáticos , Colangiocarcinoma/diagnóstico , Colangiopancreatografia Retrógrada Endoscópica/normas , Microscopía Confocal/normas , Adulto , Anciano , Neoplasias de los Conductos Biliares/complicaciones , Colangiocarcinoma/complicaciones , Constricción Patológica/diagnóstico , Constricción Patológica/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Curva ROC , Análisis de Regresión , Sensibilidad y Especificidad
18.
Physiol Genomics ; 50(9): 807-816, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30004839

RESUMEN

Extracellular superoxide dismutase (EC-SOD), one of three mammalian SOD isoforms, is the sole extracellular enzymatic defense against superoxide. A known human single nucleotide polymorphism (SNP) in the matrix-binding domain of EC-SOD characterized by an arginine-to-glycine substitution at position 213 (R213G) redistributes EC-SOD from the matrix into extracellular fluids. We previously reported that knock-in mice harboring the human R213G SNP (R213G mice) exhibited enhanced resolution of inflammation with subsequent protection against fibrosis following bleomycin treatment compared with wild-type (WT) littermates. Herein we set out to determine the underlying pathways with RNA-Seq analysis of WT and R213G lungs 7 days post-PBS and bleomycin. RNA-Seq analysis uncovered significant differential gene expression changes induced in WT and R213G strains in response to bleomycin. Ingenuity Pathways Analysis was used to predict differentially regulated up- and downstream processes based on transcriptional changes. Most prominent was the induction of inflammatory and immune responses in WT mice, which were suppressed in the R213G mice. Specifically, PKC signaling in T lymphocytes, IL-6, and NFΚB signaling were opposed in WT mice when compared with R213G. Several upstream regulators such as IFNγ, IRF3, and IKBKG were implicated in the divergent responses between WT and R213G mice. Our data suggest that the redistributed EC-SOD due to the R213G SNP attenuates the dysregulated inflammatory responses observed in WT mice. We speculate that redistributed EC-SOD protects against dysregulated alveolar inflammation via reprogramming of recruited immune cells toward a proresolving state.


Asunto(s)
Inflamación/genética , Inflamación/prevención & control , Polimorfismo de Nucleótido Simple/genética , Superóxido Dismutasa/genética , Animales , Bleomicina , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Inflamación/inducido químicamente , Pulmón/patología , Masculino , Ratones Endogámicos C57BL , Reproducibilidad de los Resultados , Transcriptoma/genética
19.
Clin Gastroenterol Hepatol ; 16(9): 1521-1528, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29474970

RESUMEN

BACKGROUND & AIMS: There have been few studies that compared the effects of lumen-apposing metal stents (LAMS) and double-pigtail plastic stents (DPS) in patients with peripancreatic fluid collections from pancreatitis. We aimed to compare technical and clinical success and adverse events in patients who received LAMS vs DPS for pancreatic pseudocysts and walled-off necrosis. METHODS: We performed a retrospective study of endoscopic ultrasound-mediated drainage in 149 patients (65% male; mean age, 47 y) with pancreatic pseudocysts or walled-off necrosis (97 received LAMS and 152 received DPS), from January 2011 through September 2016 at a single center. We collected data on patient characteristics, outcomes, hospitalizations, and imaging findings. Technical success was defined as LAMS insertion or a minimum of 2 DPS. Clinical success was defined as resolution of pancreatic pseudocysts or walled-off necrosis based on imaging results. The primary outcome was resolution of peripancreatic fluid collection with reduced abdominal pain or obstructive signs or symptoms. Secondary outcomes included the identification and management of adverse events, number of additional procedures required to resolve fluid collection, and the recurrence of fluid collection. RESULTS: Patients who received LAMS had larger peripancreatic fluid collections than patients who received DPS prior to intervention (P = .001), and underwent an average 1.7 interventions vs 1.9 interventions for patients who received DPS (P = .93). Technical success was achieved for 90 patients with LAMS (92.8%) vs 137 patients with DPS (90.1%) (odds ratio [OR] for success with DPS, 0.82; 95% CI, 0.33-2.0; P = .67). Despite larger fluid collections in the LAMS group, there was no significant difference in proportions of patients with clinical success following placement of LAMS (82 of 84 patients, 97.6%) vs DPS (118 of 122 patients, 96.7%) (OR for clinical success with DPS, 0.73; 95% CI, 0.13-4.0; P = .71). Adverse events developed in 24 patients who received LAMS (24.7%) vs 27 patients who received DPS (17.8%) (OR for an adverse event in a patient receiving a DPS, 0.82; 95% CI, 0.33-2.0; P = .67). However, patients with LAMS had a higher risk of pseudoaneurysm bleeding than patients with DPS (OR, 10.0; 95% CI, 1.19-84.6; P = .009). CONCLUSIONS: In a retrospective study of patients undergoing drainage of pancreatic pseudocysts or walled-off necrosis, we found LAMS and DPS to have comparable rates of technical and clinical success and adverse events. Drainage of walled-off necrosis or pancreatic pseudocysts using DPS was associated with fewer bleeding events overall, including pseudoaneurysm bleeding, but bleeding risk with LAMS should be weighed against the trend of higher actionable perforation and infection rates with DPS.


Asunto(s)
Aneurisma Falso/complicaciones , Drenaje/métodos , Hemorragia/epidemiología , Seudoquiste Pancreático/complicaciones , Stents/efectos adversos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Aneurisma Falso/cirugía , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Masculino , Metales/efectos adversos , Persona de Mediana Edad , Seudoquiste Pancreático/cirugía , Plásticos/efectos adversos , Estudios Retrospectivos , Adulto Joven
20.
J Neurol Surg B Skull Base ; 78(5): 371-379, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28875114

RESUMEN

Background Meningomas represent the most common primary intracranial tumor. The majority are benign World Health Organization (WHO) Grade I lesions, but a subset of these behave in an aggressive manner. Protein biomarkers are needed to distinguish aggressive from benign Grade I lesions. Materials and Methods Pooled protein lysates were derived from five clinically aggressive Grade I and five typically benign WHO Grade I tumors snap frozen at the time of surgery. Proteins were separated in each group using two-dimensional gel electrophoresis (2DGE) and protein spots of interest were identified using liquid chromatography-mass spectrometry (LC-MS). Potential biomarker candidates were validated using western blot assays in individual tumor samples and by tissue microarray (TMA). Results Seven candidate biomarkers were obtained from the 2DGE and validated via western blot and TMA. Biomarker validation data allowed for the creation of predictive models using binary logistical regression that correctly identified 85.9% of aggressive tumors within the larger cohort of Grade I meningioma. Conclusion Simple protein separation by 2DGE and identification of candidate biomarkers by LC-MS allowed for the identification of seven candidate biomarkers that when used in predictive models accurately distinguish aggressive from benign behavior in WHO Grade I meningioma.

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