Primitive 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 SamplesCommon bean (Phaseolus vulgaris) and soybean (Glycine max) both belong to the Phaseoleae tribe and share significant coding sequence homology. To evaluate the utility of the soybean GeneChip for transcript profiling of common bean, we hybridized cRNAs purified from nodule, leaf, and root of common bean and soybean in triplicate to the soybean GeneChip. Initial data analysis showed a decreased sensitivity and specificity in common bean cross-species hybridization (CSH) GeneChip data compared to that of soybean. We employed a method that masked putative probes targeting inter-species variable (ISV) regions between common bean and soybean. A masking signal intensity threshold was selected that optimized both sensitivity and specificity. After masking for ISV regions, the number of differentially-expressed genes identified in common bean was increased by about 2.8-fold reflecting increased sensitivity. Quantitative RT-PCR analysis of a total of 20 randomly selected genes and purine-ureides pathway genes demonstrated an increased specificity after masking for ISV regions. We also evaluated masked probe frequency per probe set to gain insight into the sequence divergence pattern between common bean and soybean. The results from this study suggested that transcript profiling in common bean can be done using the soybean GeneChip. However, a significant decrease in sensitivity and specificity can be expected. Problems associated with CSH GeneChip data can be mitigated by masking probes targeting ISV regions. In addition to transcript profiling CSH of the GeneChip in combination with masking probes in the ISV regions can be used for comparative ecological and/or evolutionary genomics studies.
Transcript profiling of common bean (Phaseolus vulgaris L.) using the GeneChip Soybean Genome Array: optimizing analysis by masking biased probes.
Specimen part
View SamplesWe used microarrays to detail the global programme of gene expression upon the over-expression of seven different differentiation-associated, E1A-regulated microRNAs.
Differentiation-associated microRNAs antagonize the Rb-E2F pathway to restrict proliferation.
Cell line
View SamplesProliferating C2C12 myoblasts were induced to differentiate into myotubes and then infected with adenovirus expressing E1A (Ad-E1A), which induces cell cycle re-entry and dedifferentiation.
Differentiation-associated microRNAs antagonize the Rb-E2F pathway to restrict proliferation.
Specimen part, Cell line, Treatment, Time
View SamplesTwo Near Isogenic soybean (Glycine max) lines were grown in hydroponic conditions with either 50uM ferric nitrate or 100uM ferric nitrate. After 10 days, half the plants were harvested (total root tissue). At 12 days after planting, iron was added to plants grown in low iron conditions bringing them up to sufficient iron growth conditions. Root tissue was harvested for the remaining plants at 14 days after planting.
An integrative approach to genomic introgression mapping.
Specimen part, Time
View SamplesPurpose: ATG41 is involved both in autophagy and zinc-deficient growth. The goal of this study is to compare transcriptomic profiles of wild-type and atg41? strains to discover autophagy-independent molecular phenotypes for the mutant. The atg1? mutant is a control for autophagy activity. Methods: Wild-type and mutant yeast were grown to mid-log phase in replete medium and shifted to zinc-deficient medium for 8 hours, after which, cells were harvested for RNA sequencing to detect differential gene expression. Results: Gene expression data for virtually every gene (~6,000) was obtained with ~12,000,000 reads per sample. Differential gene expression analysis showed that several hundred genes were differentially experessed in the atg41? mutant (greater than 2-fold) at an FDR of 0.5. Conclusions: Most strikingly, we found that the atg41? mutant transcriptome shows signs that sulfur metabolism is distrupted during zinc-deficinet growth. Expression of Met4 gene targets is increased. Overall design: mRNA from wild-type, atg1?, and atg41? yeast strains was prepared from zinc-deficient cultures in quadruplicate and sequenced. Single-end, 100bp sequencing was performed, using v4 SBS chemistry on an Illumina HiSeq2500 sequencer.
An Autophagy-Independent Role for <i>ATG41</i> in Sulfur Metabolism During Zinc Deficiency.
Cell line, Subject
View SamplesGlobal gene expression of 13 frozen samples, 6 from typical and 7 from atypical surgically resected primary lung carcinoids
Gene expression profiling reveals GC and CEACAM1 as new tools in the diagnosis of lung carcinoids.
Sex
View SamplesBackground: Venous hypertension is often present in advanced and in acute decompensated heart failure (HF). However, it is unclear whether high intravenous pressure can cause alterations in homeostasis by promoting inflammation and endothelial cell (EC) activation. We used an experimental model of acute, local venous hypertension to study the changes in circulating inflammatory mediators and EC phenotype that occur in response to biomechanical stress. Methods and Results: Twenty-four healthy subjects (14 men, age 352 years) were studied. Venous arm pressure was increased to ~30 mmHg above baseline level by inflating a tourniquet cuff around the dominant arm (test arm). Blood and endothelial cells (ECs) were sampled from test and control arm (lacking an inflated cuff) before and after 75 minutes of venous hypertension, using angiocatheters and endovascular wires. Magnetic beads coated with EC specific antibodies were used for EC separation; amplified mRNA was analyzed by Affymetrix HG-U133 2.0 Microarray. Plasma endothelin-1 (ET-1), interleukin-6 (IL-6), vascular cell adhesion molecule-1 (VCAM-1) and chemokine (C-X-C motif) ligand 2 (CXCL2) were significantly increased in the congested arm. 5,332 probe sets were differentially expressed in venous ECs before vs. after testing. Among the 143 probe sets that exhibited a significant absolute fold change >2, we identified several inflammatory mediators including ET-1, VCAM-1, and CXCL2. Conclusions: Acute experimental venous hypertension is sufficient to cause local increase in circulating inflammatory mediators and to activate venous ECs in healthy human subjects. Additional work is needed to determine the effect of venous hypertension in patients with established HF.
Peripheral venous congestion causes inflammation, neurohormonal, and endothelial cell activation.
Specimen part, Treatment, Subject
View SamplesThe wheat gene Lr34 (Yr18/Pm38/Sr57/Ltn1) encodes a putative ABCG-type of transporter and is a unique source of disease resistance providing durable and partial resistance against multiple fungal pathogens. Lr34 has been found to be functional as a transgene in barley.
The wheat resistance gene Lr34 results in the constitutive induction of multiple defense pathways in transgenic barley.
Specimen part
View SamplesTranscription factor (TF)-induced reprogramming of somatic cells into induced pluripotent stem cells (iPSC) is associated with genome-wide changes in chromatin modifications. Polycomb-mediated histone H3 lysine-27 trimethylation (H3K27me3) has been proposed as a defining mark that distinguishes the somatic from the iPSC epigenome. Here, we dissected the functional role of H3K27me3 in TF-induced reprogramming through the inactivation of the H3K27 methylase EZH2 at the onset of reprogramming. Our results demonstrate that surprisingly the establishment of functional iPSC proceeds despite global loss of H3K27me3. iPSC lacking EZH2 efficiently silenced the somatic transcriptome and differentiated into tissues derived from the three germ layers. Remarkably, the genome-wide analysis of H3K27me3 in Ezh2 mutant iPSC cells revealed the retention of this mark on a highly selected group of Polycomb targets enriched for developmental regulators controlling the expression of lineage specific genes. Erasure of H3K27me3 from these targets led to a striking impairment in TF-induced reprogramming. These results indicate that PRC2-mediated H3K27 trimethylation is required on a highly selective core of Polycomb targets whose repression enables TF-dependent cell reprogramming.
Cell reprogramming requires silencing of a core subset of polycomb targets.
Specimen part
View Samples