To identify transcriptionally regulated genes in primary mouse macrophages stimulated with LPS with high sensitivity, we isolated nascent RNA following metabolic labelling with 4-thiouridine during the last 35 min before cell harvest, as recently described (Dolken et al. 2008 RNA 14:1959-72). Microarray analyses of nascent RNA identified substantially more probe sets as up-regulated after 45 min of LPS stimulation than parallel analyses of total cellular RNA. In contrast, 4.5 h after stimulation, up-regulated genes in total and nascent RNA largely overlapped. This approach therefore allowed a much more sensitive detection of early changes in transcription, and the respective genes are likely to be direct targets of LPS-regulated transcription factors.
The phosphoproteome of toll-like receptor-activated macrophages.
Specimen part
View SamplesThe mechanisms of action of the combined targeted therapy bevacizumab erlotinib in late stage non-squamous non-small cell lung cancer was investigated by means of whole genome exon arrays.
24h-gene variation effect of combined bevacizumab/erlotinib in advanced non-squamous non-small cell lung cancer using exon array blood profiling.
Sex, Age, Specimen part, Time
View SamplesZaire ebolavirus (ZEBOV) infections are associated with high lethality in primates. ZEBOV primarily targets mononuclear phagocytes, which are activated upon infection and secrete mediators believed to trigger initial stages of pathogenesis. The characterization of the responses of target cells to ZEBOV infection may therefore not only further understanding of pathogenesis but also suggest possible points of therapeutic intervention. Gene expression profiles of primary human macrophages exposed to ZEBOV were determined using DNA microarrays and quantitative PCR to gain insight into the cellular response immediately after cell entry. Significant changes in mRNA concentrations encoding for 88 cellular proteins were observed. Most of these proteins have not yet been implicated in ZEBOV infection. Some, however, are inflammatory mediators known to be elevated during the acute phase of disease in the blood of ZEBOV-infected humans. Interestingly, the cellular response occurred within the first hour of Ebola virion exposure, i.e. prior to virus gene expression. This observation supports the hypothesis that virion binding or entry mediated by the spike glycoprotein (GP1,2) is the primary stimulus for an initial response. Indeed, ZEBOV virions, LPS, and virus-like particles consisting of only the ZEBOV matrix protein VP40 and GP1,2 (VLPVP40-GP) triggered comparable responses in macrophages, including pro-inflammatory and pro-apoptotic signals. In contrast, VLPVP40 (particles lacking GP1,2) caused an aberrant response. Notably, some cellular interferon-inducible genes were upregulated six hours after exposure to virions and LPS, but not after exposure to VLPVP40-GP. This suggests that GP1,2 binding to macrophages plays an important role in the immediate cellular response.
Ebola virion attachment and entry into human macrophages profoundly effects early cellular gene expression.
Disease, Disease stage, Subject
View SamplesG protein-coupled receptor kinase 2 (GRK2) has emerged as a key regulator of cardiac function and myocardial structure. Cardiac GRK2 is increased in heart failure and ischemia in humans, whereas genetic inhibition of GRK2 is cardioprotective in animal models of these pathologies. However, the mechanistic basis underlying these effects are not fully understood. We have used adult GRK2 hemizygous mice (GRK2+/-) as a model to assess the effects of a sustained systemic inhibition of GRK2 in heart tissue with age.
Downregulation of G protein-coupled receptor kinase 2 levels enhances cardiac insulin sensitivity and switches on cardioprotective gene expression patterns.
Specimen part
View SamplesIn the current study, we used exon arrays and clinical samples from a previous trial (SAKK 19/05) to investigate the expression variations at the exon-level of 3 genes potentially playing a key role in modulating treatment response (EGFR, KRAS, VEGFA).
EGFR exon-level biomarkers of the response to bevacizumab/erlotinib in non-small cell lung cancer.
Sex, Specimen part, Disease, Disease stage, Treatment
View SamplesAtypical teratoid/rhabdoid tumor (ATRT) is one of the most common brain tumors in infants. Although the prognosis of ATRT patients is poor, some patients respond favorably to current treatments, suggesting molecular inter-tumor heterogeneity. To investigate this further, we genetically and epigenetically analyzed a large series of human ATRTs. Three distinct molecular subgroups of ATRTs, associated with differences in demographics, tumor location, and type of SMARCB1 alterations, were identified. Whole-genome DNA and RNA sequencing found no recurrent mutations in addition to SMARCB1 that would explain the differences between subgroups. Whole-genome bisulfite sequencing and H3K27Ac chromatin-immunoprecipitation sequencing of primary tumors, however, revealed clear differences, leading to the identification of subgroup-specific regulatory networks and potential therapeutic targets.
Atypical Teratoid/Rhabdoid Tumors Are Comprised of Three Epigenetic Subgroups with Distinct Enhancer Landscapes.
Sex, Age
View SamplesWhole exome sequencing identified frequent driver mutations in a series of paediatric glioblastomas
Driver mutations in histone H3.3 and chromatin remodelling genes in paediatric glioblastoma.
Sex, Age, Disease, Disease stage
View SamplesGlioblastoma (GBM) is an incurable brain tumor carrying a dismal prognosis, which displays considerable heterogeneity. We have recently identified recurrent H3F3A mutations affecting two critical positions of histone H3.3 (K27, G34) in one-third of pediatric GBM. Here we show that each of these H3F3A mutations defines an epigenetic subgroup of GBM with a distinct global methylation pattern, and are mutually exclusive with IDH1 mutation (characterizing a CpG-Island Methylator Phenotype (CIMP) subgroup). Three further epigenetic subgroups were enriched for hallmark genetic events of adult GBM (EGFR amplification, CDKN2A/B deletion) and/or known transcriptomic signatures. We also demonstrate that the two H3F3A mutations give rise to GBMs in separate anatomic compartments, with differential regulation of OLIG1/2 and FOXG1, possibly reflecting different cellular origins.
Hotspot mutations in H3F3A and IDH1 define distinct epigenetic and biological subgroups of glioblastoma.
Sex
View SamplesPrimitive neuroectodermal tumors of the central nervous system (CNS PNETs) are highly aggressive, poorly differentiated embryonal tumors occurring predominantly in young children. Using DNA methylation and gene expression profiling we have demonstrated that a significant proportion of institutionally diagnosed CNS PNETs display molecular profiles indistinguishable from those of various other well defined CNS tumor entities, facilitating diagnosis and appropiate therapy for children with these tumors. From the remaining fraction of CNS PNETs, we have identified four distinct new CNS tumor entities extending to other neuroepithelial tumors, each associated with a recurrent genetic alteration and particular histopathological and clinical features. These molecular entities, designated CNS Neuroblastoma with FOXR2 activation (CNS NB FOXR2), CNS Ewing sarcoma family tumor with CIC alteration (CNS EFT CIC), CNS high grade neuroepithelial tumor with MN1 alteration (CNS HGNET MN1), and CNS high grade neuroepithelial tumor with BCOR alteration (CNS HGNET BCOR), will enable meaningful clinical trials and the development of therapeutic strategies for patients affected by these poorly differentiated CNS tumors.
New Brain Tumor Entities Emerge from Molecular Classification of CNS-PNETs.
Sex, Age
View Samples