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GSE6116
Mus musculus
70 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The primary goal of toxicology and safety testing is to identify agents that have the potential to cause adverse effects in humans. Unfortunately, many of these tests have not changed significantly in the past 30 years and most are inefficient, costly, and rely heavily on the use of animals. The rodent cancer bioassay is one of these safety tests and was originally established as a screen to identify potential carcinogens that would be further analyzed in human epidemiological studies. Today, the rodent cancer bioassay has evolved into the primary means to determine the carcinogenic potential of a chemical and generate quantitative information on dose-response behavior in chemical risk assessments. Due to the resource-intensive nature of these studies, each bioassay costs $2 to $4 million and takes over three years to complete. Over the past 30 years, only 1,468 chemicals have been tested in a rodent cancer bioassay. By comparison, approximately 9,000 chemicals are used by industry in quantities greater than 10,000 lbs and nearly 90,000 chemicals have been inventoried by the U.S. Environmental Protection Agency as part of the Toxic Substances Control Act. Given the disparity between the number of chemicals tested in a rodent cancer bioassay and the number of chemicals used by industry, a more efficient and economical system of identifying chemical carcinogens needs to be developed.
Publication Title
Application of genomic biomarkers to predict increased lung tumor incidence in 2-year rodent cancer bioassays.
Sample Metadata Fields
Sex, Age, Subject
View Samples- Mus musculus
- 18 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Two-year rodent bioassays play a central role in evaluating both the carcinogenic potential of a chemical and generating quantitative information on the dose-response behavior for chemical risk assessments. The bioassays involved are expensive and time-consuming, requiring nearly lifetime exposures (two years) in mice and rats and costing $2 to $4 million per chemical. Since there are approximately 80,000 chemicals registered for commercial use in the United States and 2,000 more are added each year, applying animal bioassays to all chemicals of concern is clearly impossible. To efficiently and economically identify carcinogens prior to widespread use and human exposure, alternatives to the two-year rodent bioassay must be developed. In this study, animals were exposed for 13 weeks to two chemicals that were positive for lung tumors in the two-year rodent bioassay, two chemicals that were negative for tumors, and two vehicle controls. Gene expression analysis was performed on the lungs of the animals to assess the potential for identifying gene expression biomarkers that can predict tumor formation in a two-year bioassay following a 13 week exposure.
Publication Title
A comparison of transcriptomic and metabonomic technologies for identifying biomarkers predictive of two-year rodent cancer bioassays.
Sample Metadata Fields
Sex, Age, Subject
View Samples- Mus musculus
- 18 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Two-year rodent bioassays play a central role in evaluating both the carcinogenic potential of a chemical and generating quantitative information on the dose-response behavior for chemical risk assessments. The bioassays involved are expensive and time-consuming, requiring nearly lifetime exposures (two years) in mice and rats and costing $2 to $4 million per chemical. Since there are approximately 80,000 chemicals registered for commercial use in the United States and 2,000 more are added each year, applying animal bioassays to all chemicals of concern is clearly impossible. To efficiently and economically identify carcinogens prior to widespread use and human exposure, alternatives to the two-year rodent bioassay must be developed. In this study, animals were exposed for 13 weeks to two chemicals that were positive for liver tumors in the two-year rodent bioassay, two chemicals that were negative for liver tumors, and two vehicle controls. Gene expression analysis was performed on the livers of the animals to assess the potential for identifying gene expression biomarkers that can predict tumor formation in a two-year bioassay following a 13 week exposure.
Publication Title
A comparison of transcriptomic and metabonomic technologies for identifying biomarkers predictive of two-year rodent cancer bioassays.
Sample Metadata Fields
Sex, Age, Subject
View Samples- Homo sapiens
- 42 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
Although HSF1 is known to play an important role in regulating the cellular response to proteotoxic stressors, little is known about the structure and function of the HSF1 signaling network under both stressed and unstressed conditions. In this study, we used a combination of chromatin immunoprecipitation (ChIP) microarray analysis and time course gene expression microarray analysis with and without siRNA-mediated inhibition of HSF1 comprehensively identify genes directly and indirectly regulated by HSF1 and examine the structure of the extended HSF1 signaling network. Correlation between promoter binding and gene expression was not significant for all genes bound by HSF1 suggesting that HSF1 binding per se is not sufficient for expression. However, the correlation with promoter binding was significant for genes identified as HSF1-regulated following siRNA knockdown allowing the identification of direct transcriptional targets of HSF1. Among promoters bound by HSF1 following heat shock, a gene ontology (GO) analysis showed significant enrichment only in categories related to protein folding. In contrast, analysis of the extended HSF1 signaling network showed enrichment in a variety of categories related to protein folding, anti-apoptosis, RNA splicing, ubiquitination and others, highlighting a complex transcriptional program directly and indirectly regulated by HSF1.
Publication Title
Genome-wide analysis of human HSF1 signaling reveals a transcriptional program linked to cellular adaptation and survival.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix HT HG-U133+ PM Array Plate (hthgu133pluspm)
Description
MYC is induced early in human adipose stem cells in response to a standard MDIR adipogenic cocktail. The objective of this experiment was to identify key gene networks impacted by MYC loss-of-function in a mixed donor pool of human derived adipose stem cells.
Publication Title
MYC is an early response regulator of human adipogenesis in adipose stem cells.
Sample Metadata Fields
Sex, Race
View Samples- Homo sapiens
- 45 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
Exposure to vanadium pentoxide (V2O5) is a cause of occupational bronchitis. We evaluated gene expression profiles in cultured human lung fibroblasts exposed to V2O5 in vitro in order to identify candidate genes that could play a role in airway remodeling associated with V2O5-induced bronchitis. Gene expression was measured at various time points over a 24 hr period using the Affymetrix Human Genome U133A 2.0 Array. Expression data were preprocessed using RMA with a log2 transformation. Statistical analysis was performed in R using the affylmGUI package using a linear model with contrasts between untreated control and V2O5-exposed fibroblasts. Genes identified as statistically significant were filtered by selecting only those genes that exhibited a > 2-fold change. Quantitative real-time RT-PCR was utilized to confirm expression of selected genes. More than 2000 genes were significantly changed in response to V2O5 over the time course of our experiment. Genes altered by V2O5 were involved in biologic processes related to cell growth and differentiation, oxidative stress responses, immune regulation, and interferon signaling and apoptosis. In particular, V2O5 induced genes that encode growth factors involved in epithelial repair (HB-EGF) or angiogenesis (VEGF), peroxide generating enzymes (SOD2), pro-inflammatory enzymes (PGHS2), while suppressing genes involved in growth arrest (GAS1, STAT-1) and cell cycle inhibition (CDKN1B). Our study also identified a variety of novel genes that could be used as biomarkers of V2O5-induced bronchitis or could serve as candidate genes for disease progression.
Publication Title
Genomic analysis of human lung fibroblasts exposed to vanadium pentoxide to identify candidate genes for occupational bronchitis.
Sample Metadata Fields
No sample metadata fields
View Samples- Bos taurus
- 37 Downloadable Samples
Illumina Genome Analyzer II
Description
The estrous cycles of Limousin heifers (n = 30) were synchronized by insertion of a controlled internal drug release (CIDR) device (1.94 g progesterone; Pfizer Animal Health) placed into the vagina for 8 days. A 0.5 mg intramuscular injection of a prostaglandin F2a (PG) analogue (PG, Estrumate, Shering-Plough Animal Health, Hertfordshire, UK) was administered 1 day before CIDR removal. Heifers were checked for standing estrus and only those exhibiting estrus (Day 0) were used. All animals were expected to come in heat between 48 and 72 hours after CIDR removal. Cervical tissues were collected at slaughter from heifers 12h after CIDR removal (Group 1: CIDR + 12 h, n = 6), 24h after CIDR removal (Group 2: CIDR + 24 h, n = 6), at the onset of estrus (Group 3: Estrus, n = 4), 12 h after the onset of estrus (Group 4: estrus + 12 h, n = 5), 48 h after the onset of estrus (Group 5: Estrus+48h, n = 4) and on day 7 after the onset of estrus (Group 6: Luteal phase, n = 5). Overall design: Cervical tissue from 30 animals taken at 6 timepoints in the peri-oestrus period. +12hrs post CIDR, Onset of Oestrus,+12hrs post Oestrus, +48hrs post Oestrus, Luteal phase
Publication Title
Molecular aspects of mucin biosynthesis and mucus formation in the bovine cervix during the periestrous period.
Sample Metadata Fields
Subject, Time
View Samples- Mus musculus
- 6 Downloadable Samples
- Illumina MouseWG-6 v2.0 expression beadchip
Description
Here we report that the transcription factor cyclic AMPresponsive elementbinding protein H (CREB-H, encoded by CREB3L3) is required for the maintenance of normal plasma triglyceride concentrations. CREB-Hdeficient mice showed hypertriglyceridemia secondary to inefficient triglyceride clearance catalyzed by lipoprotein lipase (Lpl), partly due to defective expression of the Lpl coactivators Apoc2, Apoa4 and Apoa5 and concurrent augmentation of the Lpl inhibitor Apoc3. We identified multiple nonsynonymous mutations in CREB3L3 that produced hypomorphic or nonfunctional CREB-H protein in humans with extreme hypertriglyceridemia, implying a crucial role for CREB-H in human triglyceride metabolism.
Publication Title
The transcription factor cyclic AMP-responsive element-binding protein H regulates triglyceride metabolism.
Sample Metadata Fields
Sex, Specimen part, Treatment
View Samples- Mus musculus, Rattus norvegicus
- 43 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
BET bromodomains mediate transcriptional pause release in heart failure.
Sample Metadata Fields
Age, Specimen part, Treatment
View Samples- Mus musculus
- 23 Downloadable Samples
Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
Heart failure (HF) is driven via interplay between master regulatory transcription factors and dynamic alterations in chromatin structure. While pathologic gene transactivation in this context is known to be associated with recruitment of histone acetyl-transferases and local chromatin hyperacetylation, the role of epigenetic reader proteins in cardiac biology is unknown. We therefore undertook a first study of acetyl-lysine reader proteins, or bromodomains, in HF. Using a chemical genetic approach, we establish a central role for BET-family bromodomain proteins in gene control during HF pathogenesis. BET inhibition potently suppresses cardiomyocyte hypertrophy in vitro and pathologic cardiac remodeling in vivo. Integrative transcriptional and epigenomic analyses reveal that BET proteins function mechanistically as pause-release factors critical to activation of canonical master regulators and effectors that are central to HF pathogenesis and relevant to the pathobiology of failing human hearts. This study implicates epigenetic readers in cardiac biology and identifies BET co-activator proteins as therapeutic targets in HF.
Publication Title
BET bromodomains mediate transcriptional pause release in heart failure.
Sample Metadata Fields
Specimen part
View Samples