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GSE29181
Homo sapiens
11 Downloadable Samples
Illumina Genome Analyzer II
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Core transcriptional regulatory circuit controlled by the TAL1 complex in human T cell acute lymphoblastic leukemia.
Sample Metadata Fields
Disease, Cell line
View Samples- Homo sapiens
- 11 Downloadable Samples
Illumina Genome Analyzer II
Description
The oncogenic transcription factor TAL1/SCL is aberrantly overexpressed in over 40% of cases of T-cell acute lymphoblastic leukemia (T-ALL), emphasizing the importance of the TAL1-regulated transcriptional program in the molecular pathogenesis of T-ALL. Here we identify the core transcriptional regulatory circuit controlled by TAL1 and its regulatory partners HEB, E2A, GATA3, ETS1 and RUNX1 in T-ALL cells. We find that TAL1 forms an interconnected auto-regulatory loop with its partners, which contributes to the sustained upregulation of its direct target genes. Importantly, we also find the MYB oncogenic transcription factor is directly activated by the TAL1 complex and positively regulates many of the same target genes, thus forming a feed-forward positive regulatory loop that further promotes the TAL1-regulated oncogenic program.
Publication Title
Core transcriptional regulatory circuit controlled by the TAL1 complex in human T cell acute lymphoblastic leukemia.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 203 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
We performed array comparative genomic hybridization (aCGH) and gene expression profiling in 203 samples of diffuse large B cell lymphoma (DLBCL). By gene expression, at least three molecular subtypes of DLBCL termed as germinal center B cell-like (GCB) DLBCL, activated B cell-like (ABC) DLBCL, and primary mediastinal B cell lymphoma (PMBL) can be distinguished. Combining gene expression profiling and aCGH, revealed copy number abnormalities that had strikingly different frequencies in the three molecular DLBCL subtypes. These data provide genetic evidence that the DLBCL subtypes are distinct diseases that utilize different oncogenic pathways.
Publication Title
Molecular subtypes of diffuse large B-cell lymphoma arise by distinct genetic pathways.
Sample Metadata Fields
Sex, Age, Specimen part, Disease, Disease stage, Subject
View Samples- Homo sapiens
- 133 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Molecular classification of mature aggressive B-cell lymphoma using digital multiplexed gene expression on formalin-fixed paraffin-embedded biopsy specimens.
Sample Metadata Fields
Sex, Age, Specimen part, Disease
View Samples- Homo sapiens
- 43 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
The most frequent mature aggressive B-cell lymphomas are diffuse large B-cell lymphoma (DLBCL) and Burkitt lymphoma (BL). Patients suffering from molecularly defined BL (mBL) but treated with a regimen developed for DLBCL show an unfavorable outcome compared to mBL treated with chemotherapy regimens for BL. Distinguishing BL from DLBCL by conventional histopathology is challenging in lymphomas that have features common to both diseases (aggressive B-cell lymphoma unclassifiable with features of DLBCL and BL [intermediates]). Moreover, DLBCL are a heterogeneous group of lymphomas comprising distinct molecular subtypes: the activated B-cell (ABC)-like, the germinal center B-cell-like (GCB) and the unclassifyable subtype as defined by gene expression profiling (GEP). Attempts to replace GEP with techniques applicable to formalin-fixed paraffin-embedded (FFPE) tissue led to algorithms for immunohistochemical stainings (IHS). Disappointingly, the algorithms yielded conflicting results with respect to their prognostic potential, raising concerns about their validity. Furthermore, IHS algorithms did not provide a fully resolved classification: They did not identify mBL; nor did they separate ABC from unclassified DLBCL.
Publication Title
Molecular classification of mature aggressive B-cell lymphoma using digital multiplexed gene expression on formalin-fixed paraffin-embedded biopsy specimens.
Sample Metadata Fields
Sex, Age, Specimen part
View Samples- Drosophila melanogaster
- 10 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
The replication of a genomic region during S-phase can be highly dynamic between cell types that differ in transcriptome and epigenome. Replication timing has been positively correlated with several histone modifications that occur at active genes, while repressive histone modifications mark late replicating regions. This raises the question if chromatin modulates the initiating events of replication. To gain insights into this question we have studied the function of heterochromatin protein 1 (HP1), a reader of to the repressive histone lysine 9 methylation of H3, in genome-wide organization of replication. Cells with reduced levels of HP1 show an advanced replication timing of centromeric repeats in agreement with the model that repressive chromatin mediates the very late replication of large clusters of constitutive heterochromatin. Surprisingly however regions with high levels of interspersed repeats on the chromosomal arms in particular on chromosome 4 and in pericentromeric regions of chromosome 2 behave differently. Here loss of HP1 results in delayed replication timing. The fact that these regions are bound by HP1 suggests a direct effect. Thus while HP1 mediates very late replication of centromeric DNA it is also required for early replication of autosomal regions with high levels of repeats. This observation of opposing functions of HP1 suggests a model where repeat inactivation on autosomes is required for proper activation of origins of replication that fire early, while HP1 mediated repression at constitutive heterochromatin is required to ensure replication of centromeric repeats at the end of S phase.
Publication Title
Heterochromatin protein 1 (HP1) modulates replication timing of the Drosophila genome.
Sample Metadata Fields
Sex, Specimen part
View Samples- Drosophila melanogaster
- 10 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
Duplication of eukaryotic genomes during S phase is coordinated in space and time. In order to identify zones of initiation and cell-type as well as gender-specific plasticity of DNA replication, we profiled replication timing, histone acetylation and transcription throughout the Drosophila genome. We observed two waves of replication initiation with many distinct zones firing in early and multiple, less defined peaks at the end of S phase, suggesting that initiation becomes more promiscuous at the end of S phase. A comparison of different cell types revealed widespread plasticity of replication timing on autosomes. Most occur in large regions but only half coincide with local differences in transcription. In contrast to confined autosomal differences, a global shift in replication timing occurs throughout the single male X chromosome. Unlike in females, the dosage compensated X chromosome replicates almost exclusively early. This difference occurs at sites which are not transcriptionally hyperactivated, but show increased acetylation of lysine 16 of histone H4. This suggests a transcription-independent, yet chromosome-wide process related to chromatin. Importantly, H4K16ac is also enriched at initiation zones as well as early replicating regions on autosomes during S phase. Together, our data reveal novel organizational principles of DNA replication of the Drosophila genome and imply chromatin structure as a determinant of replication timing locally and chromosome-wide.
Publication Title
Chromatin state marks cell-type- and gender-specific replication of the Drosophila genome.
Sample Metadata Fields
Sex
View Samples- Oryza sativa indica group
- 18 Downloadable Samples
- Affymetrix Rice Genome Array (rice)
Description
Traditional rice varieties found in India have many desirable characteristics. Amongst them, their differential responses to abiotic and biotic stresses are of great agricultural importance. Drought or osmotic stress is one of the major abiotic stresses afflicting crop plants in India. Indigenous varieties like Dagad deshi have been found to be drought resistant and, thereby, are being studied in great detail by plant breeders and biotechnologists alike. In this study, we have analyzed the transciptomes of two contrasting cultivars, i.e. Dagad deshi (tolerant) and IR20 (susceptible), under control and stress conditions to elucidate the differences in their responses to drought stress using Affymetrix microarray platform.
Publication Title
Reference genes for accurate gene expression analyses across different tissues, developmental stages and genotypes in rice for drought tolerance.
Sample Metadata Fields
Specimen part, Time
View Samples- Mus musculus
- 26 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Chronic infection with the bacterial pathogen Helicobacter pylori is a risk factor for the development of gastric cancer, yet remains asymptomatic in a majority of individuals. We report here that the C57Bl6 mouse model of experimental infection with the closely related H. felis recapitulates this wide range in host susceptibility. A majority of infected mice develop premalignant lesions such as gastric atrophy, compensatory epithelial hyperplasia and intestinal metaplasia, whereas a minority is completely protected from preneoplasia. Protection is associated with the failure to mount an IFN-gamma response to the infection and an associated high Helicobacter burden. We demonstrate that IFN-gamma is essential for clearance of Helicobacter, but also mediates the formation of preneoplastic lesions. We further provide evidence that IFN-gamma triggers a specific transcriptional program in murine gastric epithelial cells in vitro and in vivo, and induces their preferential transformation to the hyperplastic phenotype. In summary, our data suggest a dual role for IFN-gamma in Helicobacter pathogenesis that could provide an explanation for the differential susceptibility to H. pylori-induced gastric pathology in the human population.
Publication Title
The CD4+ T cell-mediated IFN-gamma response to Helicobacter infection is essential for clearance and determines gastric cancer risk.
Sample Metadata Fields
Treatment
View Samples- Mus musculus
- 15 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Previously published data suggested some redundant functions between HDAC1 and HDAC2 in mouse. To test this hypothesis, we used microarrays to have a genome wide analysis at the transcription level of primary MEFs lacking HDAC1, HDAC2.
Publication Title
Histone deacetylases 1 and 2 act in concert to promote the G1-to-S progression.
Sample Metadata Fields
Sex
View Samples