This SuperSeries is composed of the SubSeries listed below.
Tissue-specific pioneer factors associate with androgen receptor cistromes and transcription programs.
Specimen part, Treatment
View SamplesWe report the in vivo androgen receptor (AR) binding sites in murine prostate, epididymis and kidney in response to physiological androgen testosterone using ChIP-sequencing and gene expression profiling by microarray. From AR cistrome analysis, we identified tissue-specific collaborating factors i.e. FoxA1 in prostate, Hnf4a in kidney and AP2a in epididymis and validated by ChIP-seq. The ChIP experiments have been performed using antibodies specific to AR, FoxA1, Hnf4a, AP-2a and IgG non-specific antibody as a negative control.
Tissue-specific pioneer factors associate with androgen receptor cistromes and transcription programs.
Specimen part
View SamplesWe report that the phytoestrogen genistein acts as a tissue-specific androgen receptor modulator in mouse using a novel androgen reporter mouse line and gene expression profiling. Genistein is a partial androgen agonist/antagonist in prostate, brain, and testis but not in skeletal muscle or lung. Gene expression profiling has been done from prostates of intact and castrated male mice treated with genistein or vehicle. Gene expression profiling was also done from prostates of estradiol-treated intact male mice.
The phytoestrogen genistein is a tissue-specific androgen receptor modulator.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
FoxA1 specifies unique androgen and glucocorticoid receptor binding events in prostate cancer cells.
Specimen part, Cell line, Treatment
View SamplesWe report the androgen receptor recruitment to the chromatin of androgen responsive prostate cancer cell lines, LNCaP-1F5 and VCaP in response to physiological androgen 5a-dihydrotestosterone (DHT) using ChIP-sequencing. We compare the AR recruitment by DHT to that by partial agonist/antagonist cyproterone acetate and mifepristone (RU486) in LNCaP-1F5 cells. We also report the role of glucocorticoid receptor recruitment in presence of dexamethasone (Dex) in androgen responsive prostate cancer cells. The AR and GR cistrome analysis is subsequently compared with gene expression data and RNA Pol II analysis. The ChIP-seq has been performed using AR, GR, RNA Pol II antibodies.
FoxA1 specifies unique androgen and glucocorticoid receptor binding events in prostate cancer cells.
Cell line, Treatment
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 SamplesAndrogen receptor (AR) is a ligand-dependent transcription factor that plays a key role in the onset and progression of prostate cancer. Surprisingly little is known of AR binding sites and collaborating transcription factors in the human genome. Here we have identified the DNA sequence motifs that are significantly enriched within the authentic 90 AR target regions found on chromosomes 21 and 22 in human prostate cancer cells by combining chromatin immunoprecipitation for AR with chromosome-scale tiled oligonucleotide microarrays. By integrating the DNA sequence motif data with the gene expression profiles from human prostate cancers we identified the transcription factors that recognize each of these motifs. These factors form complexes with AR, bind to specific AR target regions and govern androgen-dependent transcription. Together with AR these collaborating transcription factors form a regulatory network that directs prostate cancer growth and survival and identify potential new opportunities for therapeutic intervention.
A hierarchical network of transcription factors governs androgen receptor-dependent prostate cancer growth.
No sample metadata fields
View SamplesThe clinical efficacy of EGFR kinase inhibitors gefitinib and erlotinib is limited by the development of drug resistance. The most common mechanism of drug resistance is the secondary EGFR T790M mutation. Strategies to overcome EGFR T790M mediated drug resistance include the use of mutant selective EGFR inhibitors, including WZ4002, or by the use of high concentrations of irreversible quinazoline EGFR inhibitors such as PF299804. In the current study we develop drug resistant versions of the EGFR mutant PC9 cell line which reproducibly develops EGFR T790M as a mechanism of drug resistance to gefitinib. Neither PF299804 resistant (PFR) or WZ4002 resistant (WZR) clones of PC9 harbor EGFR T790M. Instead, they demonstrate activated IGF1R signaling as a result of loss of expression of IGFBP3 and the IGF1R inhibitor, BMS 536924, restores EGFR inhibitor sensitivity. Intriguingly, prolonged exposure to either PF299804 or WZ4002 results in the emergence of a more drug resistant subclone which contains ERK activation. A MEK inhibitor, CI-1040, partially restores sensitivity to EGFR/IGF1R inhibitor combination. Moreover, an IGF1R or MEK inhibitor used in combination with either PF299804 or WZ4002 completely prevents the emergence of drug resistant clones in this model system. Our studies suggest that more effective means of inhibiting EGFR T790M will prevent the emergence of this common drug resistance mechanism in EGFR mutant NSCLC. However, multiple drug resistance mechanisms can still emerge. Preventing the emergence of drug resistance, by targeting pathways activated in resistant cancers before they emerge, may be a more effective clinical strategy.
Resistance to irreversible EGF receptor tyrosine kinase inhibitors through a multistep mechanism involving the IGF1R pathway.
Specimen part
View SamplesGlucocorticoids (GC) are in most chemotherapy protocols for lymphoid malignancies, particularly childhood acute lymphoblastic leukaemia (ALL) for their ability to induce apoptosis in malignant blast. The underlying mechanism, however, has so far only been investigated in model systems. This study comprises Affymetrix hgu133 plus 2.0 analyses of
Identification of glucocorticoid-response genes in children with acute lymphoblastic leukemia.
No sample metadata fields
View SamplesGlucocorticoids (GC) are in most chemotherapy protocols for lymphoid malignancies, particularly childhood acute lymphoblastic leukaemia (ALL) for their ability to induce apoptosis in malignant blast. The underlying mechanism, however, has so far only been investigated in model systems. This study comprises Affymetrix hgu133 plus 2.0 analyses of
Identification of glucocorticoid-response genes in children with acute lymphoblastic leukemia.
No sample metadata fields
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