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Introduction: Enhanced recovery after surgery (ERAS) is an evidence-based, multi-modal approach to decrease surgical stress, expedite recovery, and improve postoperative outcomes. ERAS is increasingly being utilized in pediatric surgery. Its applicability to pediatric patients undergoing abdominal tumor resections remains unknown. Methods and Analysis: A group of key stakeholders adopted ERAS principles and developed a protocol suitable for the variable complexity of pediatric abdominal solid tumor resections. A multi-center, prospective, propensity-matched case control study was then developed to evaluate the feasibility of the protocol. A pilot-phase was utilized prior to enrollment of all patients older than one month of age undergoing any abdominal, retroperitoneal, or pelvic tumor resections. The primary outcome was 90-day complications per patient. Additional secondary outcomes included: ERAS protocol adherence, length of stay, time to administration of adjuvant chemotherapy, readmissions, reoperations, emergency room visits, pain scores, opioid usage, and differences in Quality of Recovery 9 scores. Ethics and Dissemination: Institutional review board approval was obtained at all participating centers. Informed consent was obtained from each participating patient. The results of this study will be presented at pertinent society meetings and published in peer-reviewed journals. We expect the results will inform peri-operative care for pediatric surgical oncology patients and provide guidance on initiation of ERAS programs. We anticipate this study will take four years to meet accrual targets and complete follow-up. Trial Registration Number: NCT04344899.
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Biliary atresia (BA) is the leading indication for pediatric liver transplantation. Rhesus rotavirus (RRV)-induced murine BA develops an obstructive cholangiopathy that mirrors the human disease. We have previously demonstrated the "SRL" motif on RRV's VP4 protein binds to heat shock cognate 70 protein (Hsc70) facilitating entry into cholangiocytes. In this study, we analyzed how binding to Hsc70 affects viral endocytosis, intracellular trafficking, and uniquely activates the signaling pathway that induces murine BA. Inhibition of clathrin- and dynamin-mediated endocytosis in cholangiocytes following infection demonstrated that blocking dynamin decreased the infectivity of RRV, whereas clathrin inhibition had no effect. Blocking early endosome trafficking resulted in decreased viral titers of RRV, whereas late endosome inhibition had no effect. After infection, TLR3 expression and p-NF-κB levels increased in cholangiocytes, leading to increased release of CXCL9 and CXCL10. Infected mice knocked out for TLR3 had decreased levels of CXCL9 and CXCL10, resulting in reduced NK cell numbers. Human patients with BA experienced an increase in CXCL10 levels, suggesting this as a possible pathway leading to biliary obstruction. Viruses that use Hsc70 for cell entry exploit a clathrin-independent pathway and traffic to the early recycling endosome uniquely activating NF-κB through TLR3, leading to the release of CXCL9 and CXCL10 and inducing NK cell recruitment. These results define how the "SRL" peptide found on RRV's VP4 protein modulates viral trafficking, inducing the host response leading to bile duct obstruction.NEW & NOTEWORTHY In this study, we have determined that the presence of the "SRL" peptide on RRV alters its method of endocytosis and intracellular trafficking through viral binding to heat shock cognate 70 protein. This initiates an inflammatory pathway that stimulates the release of cytokines associated with biliary damage and obstruction.
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Atresia Biliar , Proteínas de la Cápside , Modelos Animales de Enfermedad , Endocitosis , Infecciones por Rotavirus , Rotavirus , Atresia Biliar/metabolismo , Atresia Biliar/virología , Animales , Ratones , Infecciones por Rotavirus/metabolismo , Infecciones por Rotavirus/virología , Humanos , Proteínas de la Cápside/metabolismo , Receptor Toll-Like 3/metabolismo , Sitios de Unión , Proteínas del Choque Térmico HSC70/metabolismo , Proteínas del Choque Térmico HSC70/genética , Ratones Noqueados , FN-kappa B/metabolismo , Transducción de Señal , Clatrina/metabolismo , Ratones Endogámicos C57BL , Quimiocina CXCL10RESUMEN
Biliary atresia (BA) is a life-threatening cholangiopathy occurring in infancy, the most common indication for pediatric liver transplantation. The etiology of BA remains unknown; however, a viral etiology has been proposed as multiple viruses have been detected in explants of infants afflicted with BA. In the murine model of BA, Rhesus rotavirus (RRV) infection of newborn BALB/c pups results in a cholangiopathy that mirrors human BA. Infected BALB/c pups experience 100% symptomatology and mortality, while C57BL/6 mice are asymptomatic. Interferon-λ (IFN-λ) is an epithelial cytokine that provides protection against viral infection. We demonstrated that IFN-λ is highly expressed in C57BL/6, leading to reduced RRV replication. RRV-infection of C57BL/6 IFN-λ receptor knockout (C57BL/6 IFN-λR KO) pups resulted in 90% developing obstructive symptoms and 45% mortality with a higher viral titer in bile ducts and profound periportal inflammation compared to C57BL/6. Histology revealed complete biliary obstruction in symptomatic C57BL/6 IFN-λR KO pups, while C57BL/6 ducts were patent. These findings suggest that IFN-λ is critical in preventing RRV replication. Deficiency in IFN-λ permits RRV infection, which triggers the inflammatory cascade causing biliary obstruction. Further IFN-λ study is warranted as it may play an important role in infant susceptibility to BA.
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Atresia Biliar , Colestasis , Receptores de Interferón , Animales , Ratones , Atresia Biliar/genética , Modelos Animales de Enfermedad , Interferón lambda/metabolismo , Interferones , Ratones Endogámicos C57BL , Receptores de Interferón/genética , Receptores de Interferón/metabolismoRESUMEN
Colorectal cancer with liver metastases is a condition with significant morbidity and mortality that affects many people around the world. Many treatments exist to target liver metastases, including surgical resection, chemotherapy, nonsurgical liver-directed therapies, and liver transplantation. The field of transplant oncology is emerging as a promising alternative to palliative chemotherapy alone in appropriately selected patients. Though few clinical trials have been completed to evaluate safety of liver transplant for colorectal cancer metastases, there are several ongoing trials to hopefully make transplant a viable option for more patients with limited options.
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Neoplasias Colorrectales , Neoplasias Hepáticas , Trasplante de Hígado , Humanos , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Hepatectomía , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugíaRESUMEN
Hepatoblastoma is the most common malignant liver tumor of childhood, with liver transplant and extended resection used as surgical treatments for locally advanced tumors. Although each approach has well-described post-operative complications, quality-of-life outcomes have not been described following the two interventions. Long-term pediatric survivors of hepatoblastoma who underwent conventional liver resection or liver transplantation at a single institution from January 2000-December 2013 were recruited to complete quality-of-life surveys. Survey responses for the Pediatric Quality of Life Generic Core 4.0 (PedsQL, n = 30 patient and n = 31 parent surveys) and Pediatric Quality of Life Cancer Module 3.0 (PedsQL-Cancer, n = 29 patient and n = 31 parent surveys) were collected from patients and parents. The mean total patient-reported PedsQL score was 73.7, and the parent-reported score was 73.9. There were no significant differences in scores on the PedsQL between patients who underwent resection compared to those who underwent transplantation (p > 0.05 for all comparisons). On the PedsQL-Cancer module, procedural anxiety scores were significantly lower for patients who underwent resection as compared to transplant (M = 33.47 points less, CI [-60.41, -6.53], p-value 0.017). This cross-sectional study demonstrates that quality of life outcomes are overall similar among patients receiving transplants and resections. Patients who received a resection reported worse procedural anxiety.
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Glypican-3 (GPC3) is a cell-surface glycoprotein that is frequently overexpressed in hepatocellular carcinoma (HCC). GPC3 undergoes extensive posttranslational modification (PTM) including cleavage and glycosylation. This review focuses on the structure and function of GPC3 in liver cancer, highlighting the PTM of the tertiary and quaternary structures of GPC3 as a potential oncogenic regulatory mechanism. We propose that the function of GPC3 in normal development can vary with extensive PTM and that dysregulation of these processes leads to disease. Defining the regulatory impact of these modifications can provide a deeper understanding of the role of GPC3 in oncogenesis, epithelial-mesenchymal transition, and drug development. Through review of current literature, this article provides a unique perspective on the role of GPC3 in liver cancer, focusing on potential regulatory mechanisms of PTM on GPC3 function at the molecular, cellular, and disease level.
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Carcinoma Hepatocelular , Glipicanos , Neoplasias Hepáticas , Humanos , Carcinogénesis , Carcinoma Hepatocelular/patología , Glipicanos/química , Glipicanos/genética , Glipicanos/metabolismo , Neoplasias Hepáticas/patología , Procesamiento Proteico-PostraduccionalRESUMEN
Colorectal cancer with unresectable liver metastases has significant mortality when treated with chemotherapy alone. In appropriately selected patients, liver transplant is emerging as a treatment alternative for this population. Some key clinical trials, including SECA-I and SECA-II, have shown promising survival results: more trials are being conducted to evaluate safety of this practice.
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Neoplasias Colorrectales , Neoplasias Hepáticas , Trasplante de Hígado , Humanos , Neoplasias Colorrectales/patología , Neoplasias Hepáticas/cirugíaRESUMEN
PURPOSE: The aims of this study were to identify ultrasound-based predictors of ovarian torsion in girls without an adnexal mass and establish a set of normal values for ovarian volume ratio (OVR). METHODS: A retrospective review was performed of all premenarchal patients ≥3â¯years of age with a normal pelvic ultrasound between January 2016 and January 2019. A comparison group of premenarchal girls presenting between 2011 and 2019 with torsion in the absence of an adnexal mass was utilized. RESULTS: Five-hundred and four premenarchal girls underwent pelvic ultrasound evaluation with a normal examination. The mean OVR was 1.6⯱â¯0.7 (range 1.0-6.5). OVR did not vary with age (râ¯=â¯-0.06) as compared to ovarian width which increased steadily with age (râ¯=â¯0.53, pâ¯<â¯0.001). OVR was increased in girls with torsion (7.6 vs 1.4, pâ¯<â¯0.0001), and by receiver operating characteristic (ROC) analysis a cutoff value of >2.5 demonstrated the best diagnostic accuracy of any predictive variable (sensitivity 100%, specificity 94%, AUC 0.991, pâ¯<â¯0.001). CONCLUSIONS: OVR is an excellent predictor of ovarian torsion in premenarchal girls without an adnexal mass. Unlike ovarian width, OVR does not increase with age, and a cutoff OVRâ¯>â¯2.5 demonstrates high sensitivity and specificity for identifying ovarian torsion in this population. TYPE OF STUDY: Study of diagnostic test. LEVEL OF EVIDENCE: Level III.
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Enfermedades de los Anexos , Torsión Ovárica , Ovario , Enfermedades de los Anexos/diagnóstico por imagen , Enfermedades de los Anexos/patología , Adolescente , Niño , Preescolar , Femenino , Humanos , Tamaño de los Órganos , Torsión Ovárica/diagnóstico por imagen , Torsión Ovárica/patología , Ovario/diagnóstico por imagen , Ovario/patología , Estudios Retrospectivos , UltrasonografíaRESUMEN
Relative potency assays for biological therapeutics require statistical evaluation to demonstrate similarity between the dose-response curves of a reference standard and the test samples. We developed an equivalence testing approach that can be utilized for the complete potency assay life cycle, from early development until commercialization. This approach was based on the use of generic equivalence margins to enable equivalence testing at the beginning of assay development, when the body of assay-specific data is still very limited. Generic equivalence margins for equivalence testing of four-parameter logistic curve fits were established for bioassays and binding assays spanning a variety of designs, formats, and read-outs. We also established that equivalence testing using ratios of the reference standard and test sample was superior to equivalence testing using absolute differences. Based on a large body of historical data, generic equivalence margins were determined for the curve upper asymptote, slope, and dynamic range. Furthermore, we developed a road map to guide the implementation of generic or assay-specific margins to ensure the appropriate data analysis approach is being applied during the assay life cycle.
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Bioensayo , Estándares de ReferenciaRESUMEN
OBJECTIVE: Individuals with temporal lobe epilepsy (TLE) often experience diminished quality of life (QoL). Although comorbid depression is one of the most recognized predictors of poor QoL in TLE, impairments in verbal memory (VM) and executive functioning (EF), have also been identified as risk factors, independent of other biological and psychosocial factors. In this study, we examine the contribution of depression, VM, and EF to QoL in 52 well-characterized medically-refractory TLE patients. METHODS: Quality of life was assessed with the Quality of Life in Epilepsy (QOLIE-31) questionnaire and depression symptomatology was evaluated with the Beck Depression Inventory-II (BDI-II). Tests of VM included the California Verbal Learning Test-Second Edition and the Wechsler Memory Scale-Third Edition, Logical Memory and Verbal Paired Associates subtests. Tests of EF included the D-KEFS Category Switching and Color Word Interference Tests, and the Trail Making Test. Using these measures, a principal component (PC) was derived for VM and for EF. Hierarchical multiple linear regression analysis was used to evaluate the unique contributions of BDI-II Score, VM PC, and EF PC to the QOLIE-31 Total Score, while controlling for important clinical and demographic variables. Post-hoc analyses were also performed to examine the contribution of each variable to specific QOLIE subscales. RESULTS: Of the clinical variables, only number of antiepileptic drugs contributed to QOLIE scores. As expected, severity of depressive symptoms was the most significant predictor of QOLIE Total Score, explaining 43.4% of the variance in total QoL. The VM PC did not contribute to the QOLIE Total Score. Rather, our EF PC emerged as an important predictor of QoL, explaining an additional 5% of the variance, after controlling for clinical variables, depression severity, and VM performance. SIGNIFICANCE: These findings suggest that a combination of clinical, affective, and cognitive factors influence QoL in patients with TLE. Designing interventions with careful attention to depression and EF may be needed to optimize QoL in patients with refractory TLE and potentially other epilepsy syndromes.
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Trastornos del Conocimiento/etiología , Depresión/etiología , Epilepsia del Lóbulo Temporal/complicaciones , Epilepsia del Lóbulo Temporal/psicología , Función Ejecutiva/fisiología , Calidad de Vida/psicología , Adulto , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis de Componente Principal , Aprendizaje Verbal/fisiologíaRESUMEN
BACKGROUND: Molecular markers of WHO grade II/III glioma are known to have important prognostic and predictive implications and may be associated with unique imaging phenotypes. The purpose of this study is to determine whether three clinically relevant molecular markers identified in gliomas-IDH, 1p/19q, and MGMT status-show distinct quantitative MRI characteristics on FLAIR imaging. METHODS: Sixty-one patients with grade II/III gliomas who had molecular data and MRI available prior to radiation were included. Quantitative MRI features were extracted that measured tissue heterogeneity (homogeneity and pixel correlation) and FLAIR border distinctiveness (edge contrast; EC). T-tests were conducted to determine whether patients with different genotypes differ across the features. Logistic regression with LASSO regularization was used to determine the optimal combination of MRI and clinical features for predicting molecular subtypes. RESULTS: Patients with IDH wildtype tumors showed greater signal heterogeneity (p = 0.001) and lower EC (p = 0.008) within the FLAIR region compared to IDH mutant tumors. Among patients with IDH mutant tumors, 1p/19q co-deleted tumors had greater signal heterogeneity (p = 0.002) and lower EC (p = 0.005) compared to 1p/19q intact tumors. MGMT methylated tumors showed lower EC (p = 0.03) compared to the unmethylated group. The combination of FLAIR border distinctness, heterogeneity, and pixel correlation optimally classified tumors by IDH status. CONCLUSION: Quantitative imaging characteristics of FLAIR heterogeneity and border pattern in grade II/III gliomas may provide unique information for determining molecular status at time of initial diagnostic imaging, which may then guide subsequent surgical and medical management.
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Neoplasias Encefálicas/clasificación , Neoplasias Encefálicas/diagnóstico por imagen , Glioma/clasificación , Glioma/diagnóstico por imagen , Imagen por Resonancia Magnética , Adulto , Anciano , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Metilación de ADN , Metilasas de Modificación del ADN/genética , Metilasas de Modificación del ADN/metabolismo , Enzimas Reparadoras del ADN/genética , Enzimas Reparadoras del ADN/metabolismo , Femenino , Glioma/genética , Glioma/patología , Humanos , Imagenología Tridimensional , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estudios Retrospectivos , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo , Adulto JovenRESUMEN
The CD25-binding antibody daclizumab high-yield process (DAC HYP) is an interleukin (IL)-2 signal modulating antibody that shares primary amino acid sequence and CD25 binding affinity with Zenapax®, a distinct form of daclizumab, which was approved for the prevention of acute organ rejection in patients receiving renal transplants as part of an immunosuppressive regimen that includes cyclosporine and corticosteroids. Comparison of the physicochemical properties of the two antibody forms revealed the glycosylation profile of DAC HYP differs from Zenapax in both glycan distribution and the types of oligosaccharides, most notably high-mannose, galactosylated and galactose-α-1,3-galactose (α-Gal) oligosaccharides, resulting in a DAC HYP antibody material that is structurally distinct from Zenapax. Although neither antibody elicited complement-dependent cytotoxicity in vitro, DAC HYP antibody had significantly reduced levels of antibody-dependent cell-mediated cytotoxicity (ADCC). The ADCC activity required natural killer (NK) cells, but not monocytes, suggesting the effects were mediated through binding to Fc-gamma RIII (CD16). Incubation of each antibody with peripheral blood mononuclear cells also caused the down-modulation of CD16 expression on NK cells and the CD16 down-modulation was greater for Zenapax in comparison to that observed for DAC HYP. The substantive glycosylation differences between the two antibody forms and corresponding greater Fc-mediated effector activities by Zenapax, including cell killing activity, manifest as a difference in the biological function and pharmacology between DAC HYP and Zenapax.
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Anticuerpos Monoclonales Humanizados/farmacología , Citotoxicidad Celular Dependiente de Anticuerpos/efectos de los fármacos , Inmunoglobulina G/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Daclizumab , Glicosilación , Humanos , Subunidad alfa del Receptor de Interleucina-2/inmunología , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Leucocitos Mononucleares/inmunologíaRESUMEN
Genomic analyses have been applied extensively to analyze the process of transcription initiation in mammalian cells, but less to transcript 3' end formation and transcription termination. We used a novel approach to prepare 3' end fragments from polyadenylated RNA, and mapped the position of the poly(A) addition site using oligonucleotide arrays tiling 1% of the human genome. This approach revealed more 3' ends than had been annotated. The distribution of these ends relative to RNA polymerase II (PolII) and di- and trimethylated lysine 4 and lysine 36 of histone H3 was compared. A substantial fraction of unannotated 3' ends of RNA are intronic and antisense to the embedding gene. Poly(A) ends of annotated messages lie on average 2 kb upstream of the end of PolII binding (termination). Near the termination sites, and in some internal sites, unphosphorylated and C-terminal domain (CTD) serine 2 phosphorylated PolII (POLR2A) accumulate, suggesting pausing of the polymerase and perhaps dephosphorylation prior to release. Lysine 36 trimethylation occurs across transcribed genes, sometimes alternating with stretches of DNA in which lysine 36 dimethylation is more prominent. Lysine 36 methylation decreases at or near the site of polyadenylation, sometimes disappearing before disappearance of phosphorylated RNA PolII or release of PolII from DNA. Our results suggest that transcription termination loss of histone 3 lysine 36 methylation and later release of RNA polymerase. The latter is often associated with polymerase pausing. Overall, our study reveals extensive sites of poly(A) addition and provides insights into the events that occur during 3' end formation.
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Cromatina/metabolismo , Histonas/metabolismo , Poliadenilación , ARN Polimerasa II/metabolismo , ARN Mensajero/química , Transcripción Genética , Línea Celular , Cromatina/química , Inmunoprecipitación de Cromatina , Genómica , Células HeLa , Histonas/química , Humanos , Lisina/metabolismo , Metilación , Análisis de Secuencia por Matrices de OligonucleótidosRESUMEN
Recent progress in mapping transcription factor (TF) binding regions can largely be credited to chromatin immunoprecipitation (ChIP) technologies. We compared strategies for mapping TF binding regions in mammalian cells using two different ChIP schemes: ChIP with DNA microarray analysis (ChIP-chip) and ChIP with DNA sequencing (ChIP-PET). We first investigated parameters central to obtaining robust ChIP-chip data sets by analyzing STAT1 targets in the ENCODE regions of the human genome, and then compared ChIP-chip to ChIP-PET. We devised methods for scoring and comparing results among various tiling arrays and examined parameters such as DNA microarray format, oligonucleotide length, hybridization conditions, and the use of competitor Cot-1 DNA. The best performance was achieved with high-density oligonucleotide arrays, oligonucleotides >/=50 bases (b), the presence of competitor Cot-1 DNA and hybridizations conducted in microfluidics stations. When target identification was evaluated as a function of array number, 80%-86% of targets were identified with three or more arrays. Comparison of ChIP-chip with ChIP-PET revealed strong agreement for the highest ranked targets with less overlap for the low ranked targets. With advantages and disadvantages unique to each approach, we found that ChIP-chip and ChIP-PET are frequently complementary in their relative abilities to detect STAT1 targets for the lower ranked targets; each method detected validated targets that were missed by the other method. The most comprehensive list of STAT1 binding regions is obtained by merging results from ChIP-chip and ChIP-sequencing. Overall, this study provides information for robust identification, scoring, and validation of TF targets using ChIP-based technologies.
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Inmunoprecipitación de Cromatina , Genoma Humano , Técnicas Analíticas Microfluídicas , Análisis de Secuencia por Matrices de Oligonucleótidos , Análisis de Secuencia de ADN , Animales , Sitios de Unión/genética , Células HeLa , Humanos , Factor de Transcripción STAT1/genéticaRESUMEN
Age-related macular degeneration (AMD), the most common cause of irreversible vision loss in individuals aged older than 50 years, is classified as either wet (neovascular) or dry (nonneovascular). Inherited variation in the complement factor H gene is a major risk factor for drusen in dry AMD. Here we report that a single-nucleotide polymorphism in the promoter region of HTRA1, a serine protease gene on chromosome 10q26, is a major genetic risk factor for wet AMD. A whole-genome association mapping strategy was applied to a Chinese population, yielding a P value of <10(-11). Individuals with the risk-associated genotype were estimated to have a likelihood of developing wet AMD 10 times that of individuals with the wild-type genotype.
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Predisposición Genética a la Enfermedad , Degeneración Macular/genética , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Serina Endopeptidasas/genética , Anciano , Anciano de 80 o más Años , Envejecimiento , Pueblo Asiatico/genética , Inmunoprecipitación de Cromatina , Cromosomas Humanos Par 10/genética , Femenino , Genotipo , Células HeLa , Serina Peptidasa A1 que Requiere Temperaturas Altas , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Neovascularización Retiniana , Factor de Respuesta Sérica/metabolismo , Factor de Transcripción AP-2/metabolismoRESUMEN
The STAT (signal transducer and activator of transcription) proteins play a crucial role in the regulation of gene expression, but their targets and the manner in which they select them remain largely unknown. Using chromatin immunoprecipitation and DNA microarray analysis (ChIP-chip), we have identified the regions of human chromosome 22 bound by STAT1 and STAT2 in interferon-treated cells. Analysis of the genomic loci proximal to these binding sites introduced new candidate STAT1 and STAT2 target genes, several of which are affiliated with proliferation and apoptosis. The genes on chromosome 22 that exhibited interferon-induced up- or down-regulated expression were determined and correlated with the STAT-binding site information, revealing the potential regulatory effects of STAT1 and STAT2 on their target genes. Importantly, the comparison of STAT1-binding sites upon interferon (IFN)-gamma and IFN-alpha treatments revealed dramatic changes in binding locations between the two treatments. The IFN-alpha induction revealed nonconserved STAT1 occupancy at IFN-gamma-induced sites, as well as novel sites of STAT1 binding not evident in IFN-gamma-treated cells. Many of these correlated with binding by STAT2, but others were STAT2 independent, suggesting that multiple mechanisms direct STAT1 binding to its targets under different activation conditions. Overall, our results reveal a wealth of new information regarding IFN/STAT-binding targets and also fundamental insights into mechanisms of regulation of gene expression in different cell states.
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Antineoplásicos/farmacología , Interferón-alfa/farmacología , Interferón gamma/farmacología , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT2/metabolismo , Transcripción Genética/efectos de los fármacos , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cromatina/metabolismo , Inmunoprecipitación de Cromatina , Cromosomas Humanos Par 22/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Células HeLa , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , Factor de Transcripción STAT1/genética , Factor de Transcripción STAT2/genéticaRESUMEN
We have mapped the chromosomal binding site distribution of a transcription factor in human cells. The NF-kappaB family of transcription factors plays an essential role in regulating the induction of genes involved in several physiological processes, including apoptosis, immunity, and inflammation. The binding sites of the NF-kappaB family member p65 were determined by using chromatin immunoprecipitation and a genomic microarray of human chromosome 22 DNA. Sites of binding were observed along the entire chromosome in both coding and noncoding regions, with an enrichment at the 5' end of genes. Strikingly, a significant proportion of binding was seen in intronic regions, demonstrating that transcription factor binding is not restricted to promoter regions. NF-kappaB binding was also found at genes whose expression was regulated by tumor necrosis factor alpha, a known inducer of NF-kappaB-dependent gene expression, as well as adjacent to genes whose expression is not affected by tumor necrosis factor alpha. Many of these latter genes are either known to be activated by NF-kappaB under other conditions or are consistent with NF-kappaB's role in the immune and apoptotic responses. Our results suggest that binding is not restricted to promoter regions and that NF-kappaB binding occurs at a significant number of genes whose expression is not altered, thereby suggesting that binding alone is not sufficient for gene activation.
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Cromosomas Humanos Par 22/genética , Cromosomas Humanos Par 22/metabolismo , FN-kappa B/metabolismo , Sitios de Unión/genética , Mapeo Cromosómico , Secuencia de Consenso , Regulación de la Expresión Génica/efectos de los fármacos , Células HeLa , Humanos , Intrones , Análisis de Secuencia por Matrices de Oligonucleótidos , Pruebas de Precipitina , Regiones Promotoras Genéticas , Proteínas Recombinantes/farmacología , Factor de Transcripción ReIA , Activación Transcripcional , Factor de Necrosis Tumoral alfa/farmacologíaRESUMEN
A DNA microarray representing nearly all of the unique sequences of human Chromosome 22 was constructed and used to measure global-transcriptional activity in placental poly(A)(+) RNA. We found that many of the known, related and predicted genes are expressed. More importantly, our study reveals twice as many transcribed bases as have been reported previously. Many of the newly discovered expressed fragments were verified by RNA blot analysis and a novel technique called differential hybridization mapping (DHM). Interestingly, a significant fraction of these novel fragments are expressed antisense to previously annotated introns. The coding potential of these novel expressed regions is supported by their sequence conservation in the mouse genome. This study has greatly increased our understanding of the biological information encoded on a human chromosome. To facilitate the dissemination of these results to the scientific community, we have developed a comprehensive Web resource to present the findings of this study and other features of human Chromosome 22 at http://array.mbb.yale.edu/chr22.