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GSE21511
Homo sapiens
12 Downloadable Samples
Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Ewing sarcoma family of tumors (ESFT) are aggressive bone and soft tissue tumors of unknown cellular origin. Most ESFT express EWS-FLI1, a chimeric protein which functions as a growth-promoting oncogene in ESFT but is toxic to most normal cells. A major difficulty in understanding EWS-FLI1 function has been the lack of an adequate model in which to study EWS-FLI1-induced transformation. Although the cell of origin of ESFT remains elusive, both mesenchymal (MSC) and neural crest (NCSC) have been implicated. We recently developed the tools to generate NCSC from human embryonic stem cells (hNCSC). In the current study we used this model to test the hypothesis that neural crest-derived stem cells are the cells of origin of ESFT and to evaluate the consequences of EWS-FLI1 expression on human neural crest biology.
Publication Title
Modeling initiation of Ewing sarcoma in human neural crest cells.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 74 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Affymetrix exon array data were generated from total RNA that was isolated from localized Ewing sarcoma biopsy specimens. Expression of transcript summarized data was compared to data generated from normal stem cells and normal adult tissues.
Publication Title
Overexpression of HOX genes is prevalent in Ewing sarcoma and is associated with altered epigenetic regulation of developmental transcription programs.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Expression profiles were generated from hESC-derived neural crest stem cells following transduction with GFP control vector or EWS-FLI1 vector. Expression was analyzed in stem cell conditions 5 days after transduction (undifferentiated conditions) and after 6 weeks in differentiation media (differentiation conditions).
Publication Title
Overexpression of HOX genes is prevalent in Ewing sarcoma and is associated with altered epigenetic regulation of developmental transcription programs.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Homo sapiens
- 4 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
The Philadelphia chromosome (Ph) encoding the oncogenic BCR-ABL1 kinase defines a subset of ALL with a particularly unfavorable prognosis. Acute lymphoblastic leukemia (ALL) cells are derived from B cell precursors in most cases and typically carry rearranged immunglobulin heavy chain (IGH) variable (V) region genes devoid of somatic mutations. Somatic hypermutation is restricted to mature germinal center B cells and depends on activation-induced cytidine deaminase (AID). Studying AID expression in 108 cases of ALL, we detected AID mRNA in 24 of 28 Ph-positive ALLs as compared to 6 of 80 Ph-negative ALLs. Forced expression of BCR-ABL1 in Ph-negative ALL cells and inhibition of the BCR-ABL1-kinase showed that aberrant expression of AID depends on BCR-ABL1 kinase activity. Consistent with aberrant AID expression in Ph-positive ALL, IGH V region genes and BCL6 were mutated in many Ph-positive but unmutated in most Ph-negative cases. In addition, AID introduced DNA-single-strand breaks within the tumor suppressor gene CDKN2B in Ph-positive ALL cells, which was sensitive to BCR-ABL1 kinase inhibition and silencing of AID expression by RNA interference. These findings identify AID as a BCR-ABL1-induced mutator in Ph-positive ALL cells, which may be relevant with respect to the particularly unfavorable prognosis of this leukemia subset.
Publication Title
Activation-induced cytidine deaminase acts as a mutator in BCR-ABL1-transformed acute lymphoblastic leukemia cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 7 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Affymetrix gene expression AID-GFP-positive vs AID-GFP-negative
Publication Title
The B cell mutator AID promotes B lymphoid blast crisis and drug resistance in chronic myeloid leukemia.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Precursor B-lineage acute lymphoblastic leukemia (pre-B ALL) can be subdivided into different categories based on genetic abnormalities.
Publication Title
Pre-B cell receptor-mediated cell cycle arrest in Philadelphia chromosome-positive acute lymphoblastic leukemia requires IKAROS function.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 35 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Soft tissue sarcomas are a diverse set of fatal human tumors where few agents have demonstrable clinical efficacy, with the standard therapeutic combination of doxorubicin and ifosfamide showing only a 25-30% response rate in large multi-institutional trials. Although liposarcomas are the most common histological form of adult soft tissue sarcomas, research in this area is severely hampered by the lack of experimentally tractable in vitro model systems. To this end, here we describe a novel in vitro model for human pleomorphic liposarcoma. The cell line (LS2) is derived from a pleomorphic liposarcoma that utilizes Alternative Lengthening of Telomeres (ALT) mechanism of telomere maintenance, which may be particularly important in modulating the response of this tumor type to DNA damaging agents. We present detailed baseline molecular and genomic data, including genome wide copy number and transcriptome profiles, for this model compared to its parental tumor and a panel of liposarcomas covering multiple histologies. The model has retained essentially all of the detectable alterations in copy number that are seen in the parental tumor, and shows molecular karyotypic and expression profiles consistent with pleomorphic liposarcomas. We also demonstrate the utility of this model, together with two additional human liposarcoma cell lines, to investigate the relationship between topoisomerase 2A expression and the sensitivity of ALT-positive liposarcomas to doxorubicin. This model, together with its associated baseline data, provide a powerful new tool to develop treatments for this clinically poorly-tractable tumor, and to investigate the contribution that ALT makes to modulating sensitivity to DNA damaging chemotherapeutic agents such as doxorubicin.
Publication Title
Doxorubicin resistance in a novel in vitro model of human pleomorphic liposarcoma associated with alternative lengthening of telomeres.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 37 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
A gene expression signature purporting to distinguish between telomerase and ALT immortalization has recently been described (Lafferty-Whyte et al., 2009). This was obtained as the intersection of two independent signatures, one obtained from cell lines and the other from a panel of liposarcomas, which utilize different telomere maintenance mechanisms (TMMs). To assess the utility of this signature we used Affymetrix U133plus2.0 arrays to undertake a similar analysis of an independent collection of liposarcomas of defined TMM. In our dataset, the 297 gene signature causes the liposarcomas to cluster not on the basis of TMM, but rather on the basis of tumor histological subtype [Figure 1], consistent with the signatures reported by others (Matushansky et al., 2008).
Publication Title
Validating a gene expression signature proposed to differentiate liposarcomas that use different telomere maintenance mechanisms.
Sample Metadata Fields
No sample metadata fields
View Samples- Caenorhabditis elegans
- 8 Downloadable Samples
- Affymetrix C. elegans Genome Array (celegans)
Description
Background: DNA microarrays provide a powerful method for global analysis of gene expression. The application of this technology to specific cell types and tissues, however, is typically limited by small amounts of available mRNA, thereby necessitating amplification. Here we compare microarray results obtained with two different methods of RNA amplification to profile gene expression in the C. elegans larval nervous system. Results: We used the mRNA-tagging strategy to isolate transcripts specifically from C. elegans larval neurons. The WT-Ovation Pico System (WT-Pico) was used to amplify 2 ng of Pan-neural RNA to produce labeled cDNA for microarray analysis. These WT-Pico-derived data were compared to microarray results obtained with a labeled aRNA target generated by two rounds of In Vitro Transcription (IVT) of 25 ng of Pan-neural RNA. WT-Pico results in a higher fraction of Present calls than IVT, a finding consistent with the proposal that DNA-DNA hybridization results in lower mismatch signals than the RNA-DNA heteroduplexes produced by IVT amplification. Microarray data sets from these samples were compared to a Reference profile of all larval cells to identify transcripts with elevated expression in neurons. These results were validated by the high proportion of known neuron-expressed genes detected in these profiles and by promoter-GFP constructs for previously uncharacterized genes in these data sets. Together, the IVT and WT-Pico methods identified 2,173 unique neuron-enriched transcripts. Only about half of these transcripts (1,044), however, are detected as enriched by both IVT and WT-Pico amplification.
Publication Title
Complementary RNA amplification methods enhance microarray identification of transcripts expressed in the C. elegans nervous system.
Sample Metadata Fields
No sample metadata fields
View Samples- Drosophila melanogaster
- 15 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
Centrosome defects are a common feature of many cancers. Surprisingly, flies can proceed through the majority of development without centrosomes or with amplified centrosomes in most of their cells. It is unclear whether this is because centrosome defects do not cause many problems in Drosophila cells, or because they can adapt to cope with any problems that arise. Indeed, centrosome loss and centrosome amplification predispose fly brain cells to form tumours. Here we assess how centrosome loss or centrosome amplification perturbs cell physiology by profiling the global transcriptome of Drosophila larval brains and imaginal discs that either lack centrosomes or have too many centrosomes.
Publication Title
Centrosome loss or amplification does not dramatically perturb global gene expression in Drosophila.
Sample Metadata Fields
Specimen part
View Samples