Einleitung:
Die adjuvante Standard-Chemotherapie bei Ovarialkarzinompatientinnen enthält Platin. Obwohl anfänglich 80% der Patientinnen ein klinisches Ansprechen zeigen, entwickeln die meisten von ...ihnen ein Pt-resistentes Rezidiv. Bei diesem Prozess sind, neben neu erworbenen genetischen Aberrationen auch epigenetische Veränderungen von Bedeutung. Ziel dieser Studie ist die Untersuchung von Genen, deren Promotor während der
in-vitro
Pt-Resistenz-Entwicklung im Zellkulturmodell hypermethyliert wird.
Methoden:
Resistente Subklone der Zelllinien A2780, SKOV3 und HeyA8 wurden durch langzeitige Kultivierung unter stufenweise steigender Cisplatinkonzentration generiert. Hypermethylierte CpG Inseln wurden, nach Anreicherung von methylierter DNA aus sensitiven bzw. resistenten Zellkulturen (MIRA-Methylated CpG-Island Recovery Assay), mittels vergleichender Microarrayhybridisierung identifiziert und durch methylierungsspezifische PCR validiert. Die Bestimmung der Expression von hypermethylierten Genen erfolgte mittels real-time PCR. Die funktionelle Bedeutung hypermethylierter Gene wurde durch Überxpression in resistenten bzw. shRNA-vermittelten knock-down in sensitiven Zellen ermittelt.
Ergebnisse:
Microarray-Analysen identifizierten 37 CpG Inseln die während der Resistenzentwicklung in allen 3 Zelllinienpaaren hypermethyliert wurden. Dabei zeigten vier von 25 analysierten Genen eine verringerte Expression in den resistenten Zellen. Insbesondere wiesen sensitive Zellen eine erhöhte Expression während der Cisplatinexposition in Abhängigkeit von der Konzentration und Behandlungsdauer auf. Bisherige Überexpressionsexperimente zeigen teilweise eine veränderte Sensitivität auf Cisplatin für die transfizierten Zellen. Dies wird sowohl anhand von Einzelzellklonen als auch shRNA Experimenten validiert.
Schlussfolgerung:
Die Entwicklung von Cisplatinresistenz
in-vitro
ist mit der Hypermethylierung von CpG-Inseln und der einhergehenden Hemmung der Expression betroffener Gene assoziiert. Erste funktionelle Daten weisen diesen Vorgängen auch eine funktionelle Bedeutung zu, die jedoch weitergehend validiert werden muss.
Previous reports have indicated that the short term prognosis for patients with malignant diseases and serious adverse events requiring mechanical ventilation (SAEV) is improving. The purpose of this ...study was to determine whether these patients can be cured of malignant disease or whether they survive SAEV only to subsequently relapse.
The authors report the outcome of children with SAEV treated in the multicentre studies ALL-BFM 95 and AML-BFM 98. Data from 1182 patients with acute lymphoblastic leukaemia (ALL) and 334 patients with acute myeloid leukaemia (AML) were analysed. 88 patients (51 ALL and 37 AML) developed SAEV.
The prognosis was almost identical in ALL and AML patients (survival of SAEV patients: 48%, 95% CI 38% to 58%; overall survival after 5 years: 31%, 95% CI 21% to 41%). Prognosis was independent of the time between leukaemia diagnosis and SAEV. Approximately 20% of children who required haemodialysis (n=14) or cardiac resuscitation (n=16) achieved long term survival, but no patient who fulfilled more than three of six identified risk factors (age ≥10 years, high risk leukaemia, C reactive protein ≥150 mg/l, administration of inotropic infusion, cardiac resuscitation and haemodialysis) survived (n=16; 0%, 95% CI 0% to 20%).
Intensive care improves the short and long term survival of children with leukaemia. 64% (95% CI 50% to 78%) of children with acute leukaemia who survived SAEV achieved long term survival. Prognosis mainly depends on age and leukaemia risk group.
Background Epigenetic marks are heritable, influenced by the environment, direct the maturation of T lymphocytes, and in mice enhance the development of allergic airway disease. Thus it is important ...to define epigenetic alterations in asthmatic populations. Objective We hypothesize that epigenetic alterations in circulating PBMCs are associated with allergic asthma. Methods We compared DNA methylation patterns and gene expression in inner-city children with persistent atopic asthma versus healthy control subjects by using DNA and RNA from PBMCs. Results were validated in an independent population of asthmatic patients. Results Comparing asthmatic patients (n = 97) with control subjects (n = 97), we identified 81 regions that were differentially methylated. Several immune genes were hypomethylated in asthma, including IL13 , RUNX3 , and specific genes relevant to T lymphocytes ( TIGIT ). Among asthmatic patients, 11 differentially methylated regions were associated with higher serum IgE concentrations, and 16 were associated with percent predicted FEV1 . Hypomethylated and hypermethylated regions were associated with increased and decreased gene expression, respectively ( P < 6 × 10−12 for asthma and P < .01 for IgE). We further explored the relationship between DNA methylation and gene expression using an integrative analysis and identified additional candidates relevant to asthma ( IL4 and ST2 ). Methylation marks involved in T-cell maturation (RUNX3) , TH 2 immunity (IL4) , and oxidative stress (catalase) were validated in an independent asthmatic cohort of children living in the inner city. Conclusions Our results demonstrate that DNA methylation marks in specific gene loci are associated with asthma and suggest that epigenetic changes might play a role in establishing the immune phenotype associated with asthma.
Abstract X-linked hyper-immunoglobulin M syndrome (XHIGM) is a primary immunodeficiency disorder characterized by severe defects of both cellular and humoral immunity due to impaired expression of ...CD40 ligand on activated T lymphocytes. Patients with XHIGM usually present with a wide variety of infections caused by common and opportunistic pathogens including Pneumocystis jirovecii . In addition, subjects with XHIGM have an increased risk for hepatocellular and bile duct carcinomas, which are rarely observed in other primary immunodeficiencies. We present here clinical, immunological, and molecular findings of four patients with CD40 ligand deficiency associated with neuroendocrine carcinoma (NEC). NEC developed as a rapidly disseminated solid cancer leading to death in three patients. Data presented here and published previously suggest that CD40 ligand deficiency may predispose patients for the development of NEC. Histochemical findings suggested that CD56, in addition to cytokeratin and chromogranin A, may be a useful marker for early detection of NEC. We conclude that patients with XHIGM should be carefully followed to diagnose and treat NEC, a formidable neuroendocrine cancer.
In this work we present electrical measurements with a current flow being spatially defined on a μm scale. We examine the effect of the grain structure on the electrical transport properties of ...B-doped diamond films grown on large-area HOD films depending on temperature and field strength. The results are discussed with regard to film morphology. Bridges as narrow as 3.0
μm are etched and contacted in a well-defined way using Ti/Pt/Au contacts. Our experiments and analysis indicate that the electrical transport is not dominated by grain boundaries perpendicular to current flow. Using HOD films with a grain size of up to 10
μm as determined by scanning electron microscopy (SEM) we prepare bridges where a single grain boundary intersects the bridge or connects the two ends, as well as bridges where no grain boundary is present. These measurements on single grain boundaries are a tool to reveal the fundamentals of the current transport properties.
Aim:
To identify and validate highly discriminating DNA methylation markers for the triage of hrHPV-positive women with or without clinically relevant lesions.
Methods:
Hypermethylated DNA enriched ...from cervical cancers was compared with that from cervical scrapes of HPV16-positive cases with no evidence for disease by CpG island microarray hybridization. The most promising marker regions were validated by quantitative methylation-specific PCR (qMSP) using DNA from archived cervical tissues and cervical scrapes. The performance of these markers was then determined in an independent set of 217 hrHPV-positive cervical scrapes from outpatients with histopathological verification.
Results:
A methylation signature comprising the 5'regions of the genes
DLX1, ITGA4, RXFP3, SOX17
and
ZNF671
specific for CIN3 and cervical cancer (termed CIN3+) was identified and validated. A high detection rate of CIN3+ was obtained if at least 2 of the 5 markers were methylated. In the subsequent cross-sectional study our marker panel achieved a sensitivity and specificity for CIN3+ of 96.2% (95% CI 80.4 – 100%) and 76.6% (95% CI 65.6 – 85.5%), respectively for women ≥30 years of age. By projecting the observed test performance to the target population of a HPV screening study (n = 3292) we conducted in Eastern Thuringia some years ago, the sensitivity, specificity, PPV and NPV were calculated to be 90.5%, 81.0%, 61.6% and 96.2%, respectively.
Conclusions:
Molecular triage of hrHPV-positive women by our methylation panel is feasible and opens the way to full molecular screening.
Background There is an association between adiposity and asthma prevalence, but the relationship to asthma control is unclear. Objectives We sought to understand the relationships among adiposity, ...sex, and asthma control in inner-city adolescents with asthma. Methods We prospectively followed 368 adolescents with moderate-to-severe asthma (ages 12-20 years) living in 10 urban areas for 1 year. Asthma symptoms and exacerbations were recorded, and pulmonary function and exhaled nitric oxide levels were measured every 6 weeks. Adiposity measures (body mass index BMI and dual-energy X-ray absorptiometric scans) were made, and blood was collected for measurement of allergy markers, adiponectin, leptin, TNF-α, IL-6, and C-reactive protein levels. Results More than 60% of female subjects and 50% of male subjects were above the 85th percentile of BMI for age. Higher BMI was associated with more symptom days ( R = 0.18, P = .02) and exacerbations ( R = 0.18, P = .06) among female subjects only. Adiponectin was inversely related to asthma symptoms ( R = −0.18, P < .05) and exacerbations ( R = −0.20, P < .05) and positively with FEV1 /forced vital capacity ratio ( R = 0.15, P < .05) in male subjects only independent of body size. There was no relationship between adiposity or adipokines and total IgE levels, blood eosinophil counts, and exhaled nitric oxide levels. Dual-energy X-ray absorptiometry provided little additional value in relating adiposity to asthma outcome in this population of adolescents. Conclusion Adiposity is associated with poorer asthma control in female subjects. Adiponectin is associated with improved asthma control in male subjects.
The dynamic nonequilibrium properties of a crystal electron coupled to a bath of dispersionless phonons are investigated for the strong coupling regime. The four-wave mixing experiments on the ...semiconductor ZnSe at
T=77
K use blue optical pulses of 13
fs in duration and give evidence for an oscillation with the phonon period and also evidence for an additional oscillation with half the phonon period. The latter is observed here for the first time and is an immediate consequence of the fact that, even for simultaneous emission of two phonons, coherence of an electron is preserved for some time.
Data integration is a key challenge for modern bioinformatics. It aims to provide biologists with tools to explore relevant data produced by different studies. Large-scale international projects can ...generate lots of heterogeneous and unrelated data. The challenge is to integrate this information with other publicly available data. Nucleotide sequencing throughput has been improved with new technologies; this increases the need for powerful information systems able to store, manage and explore data. GnpIS is a multispecies integrative information system dedicated to plant and fungi pests. It bridges genetic and genomic data, allowing researchers access to both genetic information (e.g. genetic maps, quantitative trait loci, markers, single nucleotide polymorphisms, germplasms and genotypes) and genomic data (e.g. genomic sequences, physical maps, genome annotation and expression data) for species of agronomical interest. GnpIS is used by both large international projects and plant science departments at the French National Institute for Agricultural Research. Here, we illustrate its use. Database URL: http://urgi.versailles.inra.fr/gnpis.
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