Filters
Technology
Platform
GSE4668
Homo sapiens
34 Downloadable Samples
Affymetrix Human Genome U133A Array (hgu133a)
Description
To obtain comprehensive information on 17beta-estradiol (E2) sensitivity of genes that are inducible or suppressible by this hormone, we designed a method that determines ligand sensitivities of large numbers of genes using DNA microarray and a set of simple Perl computer scripts implementing the standard metric statistics, and employed it to characterize effects of low (0-100 pM) concentrations of E2 on the transcriptome profile of MCF7/BUS human breast cancer cells, whose E2 dose-dependent growth curve saturated with 100 pM E2. Evaluation of changes in mRNA expression for all genes covered by the DNA microarray indicated that, at a very low concentration (10 pM), E2 suppressed 3~5 times larger numbers of genes than it induced, whereas at higher concentrations (30-100 pM) it induced 1.5~2 times more genes than it suppressed. Using clearly defined statistical criteria, E2-inducible genes were categorized into several classes based on their E2 sensitivities. This approach of hormone sensitivity analysis revealed that expression of two previously reported E2-inducible autocrine growth factors, TGF-? and SDF-1, was not affected by 100 pM and lower concentrations of E2 but strongly enhanced by 10 nM E2, which was far higher than the concentration that saturated the E2 dose-dependent growth curve of MCF7/BUS cells. These observations suggested that biological actions of E2 are derived from expression of multiple genes whose E2 sensitivities differ significantly and, hence, dependent on the E2 concentration especially when it is lower than the saturating level, emphasizing the importance of characterizing the ligand dose-dependent aspects of E2 actions. (paper abstract)
Publication Title
Global analysis of ligand sensitivity of estrogen inducible and suppressible genes in MCF7/BUS breast cancer cells by DNA microarray.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Yin Yang 1 (YY1) is a critical transcription factor controlling cell proliferation, development and DNA damage responses. Although two homologous Drosophila YY family members (pleiohomeotic (pho)) and pleiohomeotic-like (phol)) are redundant, the functional significance of a recently described mammalian YY1-like gene (YY2) is unknown. Using microarray and gene set enrichment analysis (GSEA), we found that lentiviral constructs containing short hairpin loop YY1- and YY2-specific inhibitory RNAs (shYY1 and shYY2) caused significant changes in both redundant and distinguishable expression patterns. Ribosomal protein genes were the most significant gene set up-regulated by both shYY1 and shYY2, although combined shYY1/shYY2 knockdowns were not additive. In contrast, shYY2 reversed anti-proliferative effects of shYY1 on E2F target genes, and shYY2 particularly altered UV damage response, platelet-specific genes and mitochondrial function genes. The most YY2-specific gene was the platelet glycoprotein CD36 whose ligand is thrombospondin - a key UV response gene. We found that decreases in YY1 or YY2 caused inverse changes in UV sensitivity, and that their combined loss reversed their respective individual effects. Taken together, our studies show that YY2 is not redundant to YY1, and YY2 is a significant regulator of genes previously thought to uniquely respond to YY1. Functions of thrombospondin and CD36 in inflammation, atherogenesis, innate immunity and malaria pathogenesis reveal new potential regulatory roles for YY1 and YY2.
Publication Title
Genome-wide analysis of YY2 versus YY1 target genes.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 344 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Transcriptome analysis of MCF-7 cells exposed for 48 hours to various concentrations of xenoestrogen chemicals.
Publication Title
Expressomal approach for comprehensive analysis and visualization of ligand sensitivities of xenoestrogen responsive genes.
Sample Metadata Fields
Cell line
View Samples- Mus musculus
- 24 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Huntingtons disease (HD) involves marked early neurodegeneration in the striatum whereas the cerebellum is relatively spared despite the ubiquitous expression of full-length mutant huntingtin, implying that inherent tissue-specific differences determine susceptibility to the HD CAG mutation. To understand this tissue specificity, we compared early mutant huntingtin-induced gene expression changes in striatum to those in cerebellum in young Hdh CAG knock-in mice, prior to onset of evident pathological alterations. Endogenous levels of full-length mutant huntingtin caused qualitatively similar, but quantitatively different gene expression changes in the two brain regions. Importantly, the quantitatively different responses in striatum and cerebellum in mutant mice were well accounted for by the intrinsic molecular differences in gene expression between striatum and cerebellum in wild-type animals. Tissue-specific gene expression changes in response to the HD mutation, therefore, appear to reflect the different inherent capacities of these tissues to buffer qualitatively similar effects of mutant huntingtin. These findings highlight a role for intrinsic quantitative tissue differences in contributing to HD pathogenesis, and likely to other neurodegenerative disorders exhibiting tissue-specificity, thereby guiding the search for effective therapeutic interventions.
Publication Title
Differential effects of the Huntington's disease CAG mutation in striatum and cerebellum are quantitative not qualitative.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 9 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Developmental exposure of mouse fetuses to estrogens results in dose-dependent permanent effects on prostate morphology and function. Fetal prostatic mesenchyme cells express estrogen receptor alpha (ER) and androgen receptors and convert stimuli from estrogens and androgens into signaling to regulate epithelial cell proliferation and differentiation. To obtain mechanistic insight into the role of different doses of estradiol (E2) in regulating mesenchymal cells, we examined E2-induced transcriptomal changes in primary cultures of fetal mouse prostate mesenchymal cells. Urogenital sinus mesenchyme cells were obtained from male mouse fetuses at gestation day 17 and exposed to 10 pM, 100 pM or 100 nM E2 in the presence of a physiological concentration of dihydrotestosterone (0.69 nM) for four days. Gene ontology studies suggested that low doses of E2 (10 pM and 100 pM) induce genes involved in cell adhesion, morphological tissue development, and sterol biosynthesis but suppress genes involved in growth factor signaling and cell adhesion. Genes showing inverted-U-shape dose responses (enhanced by E2 at 10 pM E2 but suppressed at 100 pM) were identified, and their enrichment in the glycolytic pathway was demonstrated. At the highest dose (100 nM), E2 induced genes enriched not only for cell adhesion but also steroid hormone signaling and metabolism, cytokines and their receptors, cell-to-cell communication, Wnt signaling, and TGF- signaling. These results suggest that prostate mesenchymal cells may regulate epithelial cells through direct cell contacts when estrogen level is low whereas soluble growth factors might play significant roles when estrogen level is high.
Publication Title
Dose-related estrogen effects on gene expression in fetal mouse prostate mesenchymal cells.
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Expression 430A Array (moe430a)
Description
Developmental estrogen exposure causes permanent alterations to mouse prostate development. Fetal prostatic mesenchyme cells regulate epithelial cell proliferation and differentiation, and alterations to mesenchymal regulation of prostate epithelial cell proliferation and differentiation may lead to permanent changes in gland structure and function. Our goal was to understand how mesenchymal cells convert estrogen signaling to stimuli that affect epithelial cells. We used microarrays to identify estrogen-induced transcriptomal changes in primary cultures of fetal mouse prostate mesenchymal cells.
Publication Title
Dose-related estrogen effects on gene expression in fetal mouse prostate mesenchymal cells.
Sample Metadata Fields
Sex, Specimen part, Treatment
View Samples- Homo sapiens
- 25 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Emergence of antiestrogen-resistant cells in MCF-7 cells during suppression of estrogen signaling is a widely accepted model of acquired breast cancer resistance to endocrine therapy. To obtain insight into the genomic basis of endocrine therapy resistance, we characterized MCF-7 monoclonal sublines that survived 21-day exposure to tamoxifen (T-series sublines) or fulvestrant (F-series sublines) and sublines unselected by drugs (U-series). All T/F-sublines were resistant to the cytocidal effects of both tamoxifen and fulvestrant. However, their responses to the cytostatic effects of fulvestrant varied greatly, and their remarkably diversified morphology showed no correlation with drug resistance. mRNA expression profiles of the U-sublines differed significantly from those of the T/F-sublines, whose transcriptomal responsiveness to fulvestrant was largely lost. A set of genes strongly expressed in the U-sublines successfully predicted metastasis-free survival of breast cancer patients. Most T/F-sublines shared highly homogeneous genomic DNA aberration patterns that were distinct from those of the U-sublines. Genomic DNA of the U-sublines harbored many aberrations that were not found in the T/F-sublines. These results suggest that the T/F-sublines are derived from a common monoclonal progenitor that lost transcriptomal responsiveness to antiestrogens as a consequence of genetic abnormalities many population doublings ago, not from the antiestrogen-sensitive cells in the same culture during the exposure to antiestrogens. Thus, the apparent acquisition of antiestrogen resistance by MCF-7 cells reflects selection of preexisting drug-resistant subpopulations without involving changes in individual cells. Our results suggest the importance of clonal selection in endocrine therapy resistance of breast cancer.
Publication Title
Antiestrogen-resistant subclones of MCF-7 human breast cancer cells are derived from a common monoclonal drug-resistant progenitor.
Sample Metadata Fields
Specimen part, Cell line, Treatment
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Follicular lymphoma (FL) is an indolent lymphoma associated with follicular center B cells, and typically contains the Bcl-2 chromosomal translocation t(14;18), which leads to overexpression of the anti-apoptotic intracellular protein Bcl-2. FLs are sensitive to chemotherapy; however, patient relapses occur and response duration becomes progressively shorter, with the majority of patients eventually dying from the disease. Enzastaurin (LY317615), an acyclic bisindolylmaleimide, was initially developed as an ATP-competitive selective inhibitor of PKC. We found, in agreement with recent reports, that enzastaurin inhibits cell proliferation and induces apoptosis. These results are consistent with decreased phosphorylation of the Akt pathway and its downstream targets. To provide new insights into the anti-tumor action of enzastaurin on non-Hodgkin lymphoma, we investigated its effects on gene expression profiles of the B cell lymphoma RL cell line by oligonucleotide microarray analysis. We identified a set of 41 differentially expressed genes, mainly involved in cellular adhesion, apoptosis, inflammation, and immune and defense responses. These observations provide new insights into the mechanisms involved in the induction of apoptosis by enzastaurin in B cell lymphoma cell lines, and identify possible pathways that may contribute to the induction of apoptosis.
Publication Title
Genomic profiling of enzastaurin-treated B cell lymphoma RL cells.
Sample Metadata Fields
Specimen part, Cell line, Treatment
View Samples- Homo sapiens
- 221 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
In Huntingtons disease (HD), expanded HTT CAG repeat length correlates strongly with age at motor onset, indicating that it determines the rate of the disease process leading to diagnostic clinical manifestations. Similarly, in normal individuals, HTT CAG repeat length is correlated with biochemical differences that reveal it as a functional polymorphism. Here, we tested the hypothesis that gene expression signatures can capture continuous, length-dependent effects of the HTT CAG repeat. Using gene expression datasets for 107 HD and control lymphoblastoid cell lines, we constructed mathematical models in an iterative manner, based upon CAG correlated gene expression patterns in randomly chosen training samples, and tested their predictive power in test samples. Predicted CAG repeat lengths were significantly correlated with experimentally determined CAG repeat lengths, whereas models based upon randomly permuted CAGs were not at all predictive. Predictions from different batches of mRNA for the same cell lines were significantly correlated, implying that CAG length-correlated gene expression is reproducible. Notably, HTT expression was not itself correlated with HTT CAG repeat length. Taken together, these findings confirm the concept of a gene expression signature representing the continuous effect of HTT CAG length and not primarily dependent on the level of huntingtin expression. Such global and unbiased approaches, applied to additional cell types and tissues, may facilitate the discovery of therapies for HD by providing a comprehensive view of molecular changes triggered by HTT CAG repeat length for use in screening for and testing compounds that reverse effects of the HTT CAG expansion.
Publication Title
Dominant effects of the Huntington's disease HTT CAG repeat length are captured in gene-expression data sets by a continuous analysis mathematical modeling strategy.
Sample Metadata Fields
Sex
View Samples- Homo sapiens
- 100 Downloadable Samples
- Affymetrix Human Transcriptome Array 2.0 (hta20)
Description
Triple negative breast cancer (TNBC) represents a challenging tumor type due to their poor prognosis and limited treatment options. It is well recognize that clinical and molecular heterogeneity of TNBC is driven in part by mRNA and lncRNAs. To stratify TNBCs, we profiled mRNAs and lncRNA in 158 adjuvant TNBC tumors using an Affymetrix microarray platform. Lehmann clustering analysis allowed us to identify TNBC subtypes featuring unique lncRNA expression patterns, disease free and overall survival rates and particular gene ontology enrichments (performed with GSEA algorithm).
Publication Title
Loss of function of miR-342-3p results in MCT1 over-expression and contributes to oncogenic metabolic reprogramming in triple negative breast cancer.
Sample Metadata Fields
Specimen part
View Samples