Androgen receptor (AR) is typically overexpressed in castration-resistant prostate cancer (CRPC). CRPC-derived VCaP cells display an excessive number of chromatin AR-binding sites (ARBs). This study analyzed direct transcription programs of the AR, the prevalence of AR enhancers and the transcriptional regulators involved in the regulation of at the enhancer regions. The analysis utilized global nuclear run-on sequencing (GRO-seq). The GRO-seq data were integrated with the ARB and VCaP cell-specific transcription factor-binding data. Androgen in 30 min activated and repressed transcription of a large number of genes including novel AR targets IGF-1 receptor and EGF receptor. GRO-seq analysis also revealed that only a fraction of the ARBs resides at functional enhancers. Activation of AR bound enhancers was most potent at the sites that also bound PIAS1, ERG and HDAC3. Our genome-wide data provide new insights how AR can directly control growth-signaling pathways in CPRC cells. Overall design: ChIP-seq samples were collected from cells treated with vehicle (ethanol, EtOH) or 10 nM R1881 (synthetic androgen methyltrienolone). IgG sample was collected from EtOH- and R1881-treated cells and used as background control. Biological duplicate samples of the AR (R1881-treated) and CTCF (vehicle- and R1881-treated) ChIP-seq samples were analyzed by using Illumina HiSeq 2000 platform 1.9. Single IgG and H3K9me3 (R1881-treated) samples were analyzed with the same platform. GRO-seq was used to determine androgen-induced changes in nascent transcription in VCaP and LNCaP cells.
Global analysis of transcription in castration-resistant prostate cancer cells uncovers active enhancers and direct androgen receptor targets.
No sample metadata fields
View SamplesAnalysis of PIAS1 co-regulation in the androgen signaling pathways in prostate cancer cell line.
SUMO ligase PIAS1 functions as a target gene selective androgen receptor coregulator on prostate cancer cell chromatin.
Cell line, Time
View SamplesCombination of platinum-based chemotherapy and radiation is currently the standard treatment for locally advanced lung cancer patients. However, therapeutic resistance to these therapies may arise from the presence of cancer stem cells (CSCs). To investigate the CSCs hypothesis of chemo-radiation resistance, we used microarray assay to profile CSCs-like cisplatin-resistant lung cancer cells (CDDP-R) versus its parental cells. CDDP-R cells were established by exposing H460 lung cancer cells to 3M cisplatin for 7 days, followed by 0.8% methylcellulose selection over 14 consecutive days.We found that CDDP-R cells expressed higher levels of stem cell markers, including CD133 and ALDH. They are more resistant to cisplatin- and etoposide-induced apoptosis and to high radiation dose (20Gy). Clonogenic assays suggest that CDDP-R cells were more resistant to radiation than parental H460 cells (DER=1.21, p<0.01). Xenograft studies suggest that CDDP-R cells were more tumorigenic (p<0.001). Microarray and comprehensive protein interaction networks analyses revealed IGFBP3 as a highly ranked hub protein which plays an important role in the mechanism of cisplatin resistance. We found reduced level of IGFBP3 and enhanced IGFR-1 activation upon IGF stimulation in CDDP-R cells. The specific targeting of IGF-1R using siRNA resulted in significant sensitization of CDDP-cells (DER=1.17, p<0.05) to radiation compared with the parental H460 cells. Our findings suggest that CDDP-R cells have the characteristics of CSCs and constitute a suitable model to study lung CSCs. Profiling of CSCs-like H460 cells led to the identification of IGF as an important pathway for chemo- and radiotherapy resistance in lung cancer.
Role of insulin-like growth factor-1 signaling pathway in cisplatin-resistant lung cancer cells.
Specimen part
View SamplesBackground: Obesity is a risk factor for breast cancer in postmenopausal women and is associated with decreased survival and less favorable clinical characteristics such as greater tumor burden, higher grade, and poor prognosis, regardless of menopausal status. Despite the negative impact of obesity on clinical outcome, molecular mechanisms through which excess adiposity influences breast cancer etiology are not well-defined.
Effect of obesity on molecular characteristics of invasive breast tumors: gene expression analysis in a large cohort of female patients.
Disease stage
View SamplesGene expression analysis of hypothalami from female animals at different juvenile developmental reproductive stages. Results provide insight into the role of the hypothalamus in controlling the onset of puberty. Overall design: SD rats were housed (8/cage) in a controlled environment and euthanized at different ages (PND=7, PND=14, Early Juvenile: 21 days, Late Juvenile: 28 days, Late Proestus (the day of first ovulation): 30-33 days. Rats were anesthetized and brains were rapidly removed. The medial basal hypothalamus (MBH) was dissected away from the rest of the brain and flash frozen. Total RNA was isolated from each sample using Qiagen''s RNeasy Mini Kit (Valencia, CA). Samples were bioanalyzed on a RNA 6000 Nano chip kit to check for integrity and concentration before sending it to OHSU''s Massively Parallel Sequencing Shared Resource for library preparation and sequencing.
Trithorax dependent changes in chromatin landscape at enhancer and promoter regions drive female puberty.
No sample metadata fields
View SamplesThe hematopoietic microenvironment consists of non-hematopoietic derived stromal elements and hematopoietic derived monocytes and macrophages which interact and function together to control the proliferation and differentiation of early blood-forming cells. Two human stromal cell lines (HS-5 and HS-27a) representing distinct functional components of this microenvironment have been extensively characterized and shown to influence monocyte gene expression. This series of gene expression profiles is intended to extend the previous studies and identify which gene expression changes may require cell-cell contact or occur in the stromal cells as a result of monocyte influence;or in the monocytes as a result of stormal influences.
Functionally and phenotypically distinct subpopulations of marrow stromal cells are fibroblast in origin and induce different fates in peripheral blood monocytes.
Sex
View SamplesThe bone marrow microenvironment is a complex mixture of cells that function in concert to regulate hematopoiesis. Cellular components include fixed nonhematopoietic stromal elements as well as monocytes and resident macrophages, which are derived from the hematopoietic stem cells. Although these monocyte-lineage cells are reported to modify stromal cell function, the reverse also occurs. Given the secretory capability of the monocyte/macrophage and their various potential functions, it is not surprising that stromal cells contained within a particular niche can modify monocyte gene expression and functional maturation.
Functionally and phenotypically distinct subpopulations of marrow stromal cells are fibroblast in origin and induce different fates in peripheral blood monocytes.
Sex
View SamplesGenomic imprinting is an epigenetic phenomenon causing parental alleles to be active depending on their parent-of-origin. In plants, imprinted genes are mainly confined to the endosperm, an ephemeral tissue supporting embryo development. Differential methylation of histone H3 on lysine 27 (H3K27me3) established by the Polycomb Repressive Complex 2 (PRC2) is a major regulatory mechanism determining activity of paternally expressed imprinted genes (PEGs) in animals and plants. Here, we show that the coding region of many PEGs is marked by an epigenetic signature of H3K27me3, H3K9me2 and CHG methylation and that the combination of these three modifications correlates with paternally-biased gene expression in the endosperm. The maternal alleles of PEGs are marked by CHG methylation in the central cell, indicating that the repressive epigenetic signature of PEGs is established before fertilization. We use the presence of the three modifications to predict novel PEGs and propose that genomic imprinting is substantially more common than previously estimated based on expression data. Overall design: Col × Ler reciprocal crosses were performed using Arabidopsis lines expressing PHE1::NTF and PHE1::BirA. 4DAP siliques were collected and tissue homogenization and nuclei purification were performed from three biological replicates for LerxCol and two for ColxLer using INTACT. Total RNA was extracted from purified nuclei using the mirVana Isolation Kit Protocol (Ambion). mRNA extraction was performed using NEBNext Poly(A) mRNA Magnetic Isolation and the Libraries were prepared with the NEBNext Ultra II RNA Library Prep Kit from Illumina. Samples were sequenced at the National Genomic Infrastructure (NGI) from SciLife Laboratory (Uppsala, Sweden) on an Illumina HiSeq2500 in paired-end 125bp read length.
Epigenetic signatures associated with imprinted paternally expressed genes in the Arabidopsis endosperm.
Specimen part, Subject
View SamplesThe rat uterus responds to acute estrogen treatment with a series of well characterized physiological responses; however, the gene expression changes required to elicit these responses have not been fully characterized. In order to understand early events induced by estrogen exposure in vivo, we evaluated the temporal gene expression in the uterus of the immature rat after a single dose of 17 Alpha-ethynyl estradiol (EE) by microarray analysis, evaluating the expression of 15,923 genes. Immature 20 day old rats were exposed to a single dose of EE (10 ug/kg) and the effect on uterine histology, weight and gene expression were determined after 1, 2, 8, 24, 48, 72 and 96 h. EE induced changes in the expression of 3,867 genes, at least at one time point (p¡Ü0.0001), and at least 1.5 fold (up- or down-regulated). Specifically, the expression of 8, 116, 3030, 2076, 381, 445, and 125 genes was modified at 1, 2, 8, 24, 48, 72 or 96 hours after exposure to EE respectively (p¡Ü0.0001, t Test). At the tissue and organ level, a clear uterotrophic response was elicited by EE after only 8 h, reaching a maximum after 24 h and remaining detectable even after 96 h of exposure. The uterine phenotypic changes were induced by sequential changes in the transcriptional status of a large number of genes, in a program that involves multiple molecular pathways. Using the gene ontology to better understand the temporal response to estrogen exposure, we determined that the earliest changes were in the expression of genes whose products are involved in transcriptional regulation and signal transduction, followed by genes implicated in protein synthesis, energy utilization, solute transport, cell proliferation and differentiation, tissue remodeling and immunological responses among other pathways. The compendium of genes here presented represents a comprehensive compilation of estrogen-responsive genes involved in the uterotrophic response.
Uterine temporal response to acute exposure to 17alpha-ethinyl estradiol in the immature rat.
Sex, Age, Specimen part, Compound, Time
View SamplesGenomic, proteomic, and metabolomic technologies continue to receive increasing interest from environmental toxicologists. This interest is due to the great potential of these technologies to identify detailed modes of action and to provide assistance in the evaluation of a contaminant’s risk to aquatic organisms. Our experimental model is the zebrafish (Danio rerio) exposed to reference endocrine disrupting compounds in order to investigate compound-induced changes in gene transcript profiles. Adult, female zebrafish were exposed to 0, 15, 40, and 100 ng/L of 17 alpha-ethynylestradiol (EE2) and concentration and time-dependent changes in hepatic gene expression were examined using Affymetrix GeneChip® Zebrafish Genome Microarrays. At 24, 48, and 168 hours, fish were sacrificed and liver mRNA was extracted for gene expression analysis (24 and 168 hours only). In an effort to link gene expression changes to effects on higher levels of biological organization, body and ovary weights were measured and blood was collected for measurement of plasma steroid hormones (17 beta-estradiol (E2), testosterone (T)) and vitellogenin (VTG) using ELISA. EE2 exposure significantly affected GSI, E2, T, VTG and gene expression. We observed 1575 genes that were significantly affected (up- or down-regulated by at least 1.5-fold (p ? 0.001) in a concentration-dependent manner by EE2 exposure at either 24 or 168 hours. EE2 exposure altered transcription of genes involved in steroid hormone homeostasis, cholesterol homeostasis, retinoic acid metabolism, and cell growth and proliferation. Plasma VTG was significantly increased at 24, 48, and 168 hours (p<0.05) at 40 and 100 ng/L and at 15 ng/L at 168 hours. E2 and T were significantly reduced following EE2 exposure at 48 and 168 hours. GSI was decreased in a dose-dependent manner at 168 hours. In this study, we identified genes involved in a variety of biological functions that have the potential to be used as markers of exposure to estrogenic substances. Future work will evaluate the use of these genes in zebrafish exposed to weak estrogens to determine if these genes are indicative of exposure to estrogens with varying potencies.
Hepatic gene expression profiling using Genechips in zebrafish exposed to 17alpha-ethynylestradiol.
Sex, Specimen part, Compound, Time
View Samples