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GSE32975
Homo sapiens
58 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Aberrant activation of signaling pathways controlled in normal epithelial cells by the epidermal growth factor receptor (EGFR) has been linked to cetuximab (a monoclonal antibody against EGFR) resistance in head and neck squamous cell carcinoma (HNSCC). To infer relevant and specific pathway activation downstream of EGFR from gene expression in HNSCC, we generated gene expression signatures using immortalized keratinocytes (HaCaT) subjected to either ligand stimulation or pharmacological inhibition of the signaling intermediaries PI-3-Kinase and MEK or transfected with EGFR, RELA/p65, or HRASVal12. The gene expression patterns that distinguished the various HaCaT variants and conditions were inferred using the Markov chain Monte Carlo (MCMC) matrix factorization algorithm Coordinated Gene Activity in Pattern Sets (CoGAPS). This approach inferred gene expression signatures with greater relevance to cell signaling pathway activation than the expression signatures inferred with standard linear models. Furthermore, the pathway signature generated using HaCaT-HRASVal12 further associated with the cetuximab treatment response in isogenic cetuximab-sensitive (UMSCC1) and -resistant (1CC8) cell lines. Our data suggest that the CoGAPS algorithm can generate gene expression signatures that are pertinent to downstream effects of receptor signaling pathway activation and potentially be useful in modeling resistance mechanisms to targeted therapies.
Publication Title
Gene expression signatures modulated by epidermal growth factor receptor activation and their relationship to cetuximab resistance in head and neck squamous cell carcinoma.
Sample Metadata Fields
Cell line, Treatment
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Genome-wide analysis in human colorectal cancer cells reveals ischemia-mediated expression of motility genes via DNA hypomethylation.
Sample Metadata Fields
Cell line, Treatment
View Samples- Danio rerio
- 12 Downloadable Samples
- Affymetrix Zebrafish Genome Array (zebrafish)
Description
A great number of studies have investigated changes induced by morphine exposure in gene expression using several experimental models. In this study, we examined gene expression changes during chronic exposure to morphine during maturation and differentiation of zebrafish CNS.
Publication Title
Whole-genome expression profile in zebrafish embryos after chronic exposure to morphine: identification of new genes associated with neuronal function and mu opioid receptor expression.
Sample Metadata Fields
Treatment
View Samples- Homo sapiens
- 8 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
DNA hypomethylation is an important epigenetic modification found to occur in many different cancer types, leading to the upregulation of previously silenced genes and loss of genomic stability. We previously demonstrated that hypoxia and hypoglycaemia (ischemia), two common micro-environmental changes in solid tumors, decrease DNA methylation through the downregulation of DNMTs in human colorectal cancer cells. Here, we utilized a genome-wide cross-platform approach to identify genes hypomethylated and upregulated by ischemia. Following exposure to hypoxia or hypoglycaemia, methylated DNA from human colorectal cancer cells (HCT116) was immunoprecipitated and analysed with an Affymetrix promoter array. Additionally, RNA was isolated and analysed in parallel with an Affymetrix expression array. Ingenuity pathway analysis software revealed that a significant proportion of the genes hypomethylated and upregulated were involved in cellular movement, including PLAUR and CYR61. A Matrigel invasion assay revealed that indeed HCT116 cells grown in hypoxic or hypoglycaemic conditions have increased mobility capabilities. Confirmation of upregulated expression of cellular movement genes was performed with qPCR. The correlation between ischemia and metastasis is well established in cancer progression, but the molecular mechanisms responsible for this common observation have not been clearly identified. Our novel results suggest that hypoxia and hypoglycaemia may be driving changes in DNA methylation through downregulation of DNMTs. This is the first report to our knowledge that provides an explanation for the increased metastatic potential seen in ischemic cells; i.e. that ischemia could be driving DNA hypomethylation and increasing expression of cellular movement genes.
Publication Title
Genome-wide analysis in human colorectal cancer cells reveals ischemia-mediated expression of motility genes via DNA hypomethylation.
Sample Metadata Fields
Cell line, Treatment
View Samples- Homo sapiens
- 46 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Chronic tendon injuries, also known as tendinopathy, are common among professional and recreational athletes. These injuries result in a significant amount of morbidity and health care expenditure and yet little is known about the molecular mechanism leading to tendinopathy. We have used histological evaluation and molecular profiling to determine the gene expression changes in 23 human patients undergoing surgical procedures for the treatment of chronic tendinopathy. Diseased tendons have altered extracellular matrix, fiber disorientation, increased cellular content and vasculature and the absence of inflammatory cells. Global gene expression profiling identified 1783 transcripts with significant different expression patterns in the diseased tendons. Global pathway analysis further suggests altered expression of extracellular matrix proteins and the lack of an appreciable inflammatory response. We have identified pathways and genes regulated in tendinopathy samples that will help contribute to the understanding of the disease towards the development of novel therapeutics.
Publication Title
Regulation of gene expression in human tendinopathy.
Sample Metadata Fields
Sex, Age, Specimen part, Disease, Disease stage, Subject
View Samples- Homo sapiens
- 10 Downloadable Samples
- Affymetrix Human Gene 2.1 ST Array (hugene21st)
Description
Immunoprecipitation of EGFR from irradiated A549 (ATCC CCL185) cells was performed in order to characterize bound mRNA species with the help of microarray analysis
Publication Title
New roles for nuclear EGFR in regulating the stability and translation of mRNAs associated with VEGF signaling.
Sample Metadata Fields
Cell line, Treatment
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Recent advances in multiple whole genome technologies provide unprecedented opportunities to profile epigenomic signatures in cancer cells. Previously we used a human gene promoter tiling microarray platform to identify genome-wide DNA methylation changes in a cell line model of breast cancer metastasis. Interestingly, the clustered nature of epigenetic targets that we identified, along with our concurrent karyotype analyses, have now led us to hypothesize that complex genomic alterations in cancer cells (deletions, translocations and ploidy) may be superimposed over promoter-specific methylation events that are responsible for gene-specific expression changes.
Publication Title
Multi-platform whole-genome microarray analyses refine the epigenetic signature of breast cancer metastasis with gene expression and copy number.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 15 Downloadable Samples
Illumina HiSeq 2000
Description
p53 induces cell death upon DNA damage, but this may not confer all of its tumor suppressor activity. We report that p53 activation enhances the processivity of DNA replication, as monitored by multi-label fiber assays, whereas removal of p53 reduces fork progression. This was observed in tumor-derived U2OS cells, but also in murine embryonic fibroblasts with heterozygous or homozygous p53 deletion, and in freshly isolated thymocytes from mice with differential p53 status. Mdm2, a p53-inducible gene product, similarly supported DNA replication even in p53-deficient cells, suggesting that sustained Mdm2-expression is at least one of the mechanisms allowing p53 to prevent replicative stress. Thus, p53 helps to protect the genome during S phase, by preventing the occurrence of stalled or collapsed replication forks. These results expand p53’s tumor-suppressive functions, adding to the ex-post model (elimination of damaged cells) an ex-ante activity, i.e. the prevention of DNA damage during replication. Overall design: Expression profiling by high throughput sequencing
Publication Title
p53 Activity Results in DNA Replication Fork Processivity.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus
- 69 Downloadable Samples
- Illumina MouseRef-8 v2.0 expression beadchip
Description
Microarray analysis revealed that changes in genes expressions are brain region-dependent; expression of several genes are affected by point mutation L100P, which was verified by RT-PCR (Lcn2, Cyr61, Slc6a12, Slc40a1, Egr2), a few genes are affected by genotype and valproate (Dusp1 and Purb), suggesting their role in valproate-induced benificial effect on sensorimotor gaiting in Disc1-L100P mutant mice. The final conclusion will be drawn after series of RT-PCR confirmation.
Publication Title
Genetic and pharmacological evidence for schizophrenia-related Disc1 interaction with GSK-3.
Sample Metadata Fields
Sex, Specimen part, Compound
View Samples- Mus musculus
- 8 Downloadable Samples
- Illumina HiSeq 2500
Description
Analysis of gene expression in WT and ATRX KO Cast x 129 Mouse ES cells Overall design: Paired end RNA-seq analysis of PolyA selected RNA and PolyA depeleted RNA from in both wildtype nd ATRX knocked out Castx129 Mouse ES Cells
Publication Title
ATRX Plays a Key Role in Maintaining Silencing at Interstitial Heterochromatic Loci and Imprinted Genes.
Sample Metadata Fields
No sample metadata fields
View Samples