Gene expression analysis under normal culture conditions (RPMI-10%FBS) and at optimal cell densities.
Low-risk susceptibility alleles in 40 human breast cancer cell lines.
Cell line
View SamplesBreast cancer is a genetically and phenotypically complex disease. To understand the role of microRNAs in this molecular complexity, we performed miRNA expression analysis in a cohort of molecularly well-characterized human breast cancer (BC) cell lines to discover miRNAs associated with the most common molecular subtypes and the most frequent genetic aberrations.Using a microarray carrying LNA modified oligonucleotide capture probes (Exiqon), expression levels of 725 human miRNAs were measured in 51 BC cell lines. MiRNA expression was explored by unsupervised cluster analysis and then associated with the molecular subtypes and genetic aberrations commonly present in breast cancer. Unsupervised cluster analysis using the most variably expressed miRNAs divided the 51 BC cell lines into a major and a minor cluster predominantly mirroring the luminal and basal intrinsic subdivision of BC cell lines. One hundred and thirteen miRNAs were differentially expressed between these two main clusters of which half were related to the ER-status of the cell lines. Forty miRNAs were differentially expressed between basal-like and normal-like/claudin-low cell lines. Within the luminal-group of cell lines, 39 miRNAs were associated with ERBB2 overexpression and 24 miRNAs with E-cadherin gene mutations, which are frequent in this subtype of BC cell lines. In contrast, 31 different miRNAs were associated with E-cadherin promoter hypermethylation, which, contrary to E-cadherin mutation, is exclusively observed in BC cell lines that are not of luminal origin. The differential expression of 30 miRNAs were associated with p16INK4 status while only a few differentially expressed miRNAs were associated with BRCA1, or PIK3CA/PTEN, TP53 mutation status of the cell lines (P-value < 0.05). Twelve miRNAs were associated with DNA copy number variation of the respective locus. Luminal-basal and epithelial-mesenchymal associated miRNAs determine the overall subdivision of miRNA transcriptome of BC cell lines. Specific sets of miRNAs were associated with ERBB2 overexpression, p16INK4aor E-cadherin mutation or E-cadherin methylation status, which implies that these miRNAs may contribute to the driver role of the genetic aberrations. Additionally, miRNAs, which are located in a genomic region showing recurrent genetic aberrations, may themselves play a driver role in breast carcinogenesis or contribute to a driver gene in their vicinity. In short, our study provides detailed molecular miRNA portraits of BC cell lines, which can be exploited for functional studies of clinically important miRNAs.
miRNA expression profiling of 51 human breast cancer cell lines reveals subtype and driver mutation-specific miRNAs.
Cell line
View SamplesARC (NSC 188491, SMA-491), 4-amino-6-hydrazino-7-beta-d-ribofuranosyl-7H-pyrrolo-(2,3-d)-pyrimidine-5-carboxamide, is a nucleoside analog with profound in vitro anti-cancer activity. First identified in a high-throughput screen for inhibitors of p21 mRNA expression, subsequent experiments showed that ARC also repressed expression of hdm2 and survivin, leading to its classification as a global inhibitor of transcription 1. The following Hu U133 plus 2.0 arrays represent single time point (24 hour) gene expression analysis of transcripts altered by ARC treatment. Arrays for the other compounds (sangivamycin and doxorubicin) are included as comparators.
ARC (NSC 188491) has identical activity to Sangivamycin (NSC 65346) including inhibition of both P-TEFb and PKC.
No sample metadata fields
View SamplesETS1 and RAS/ERK regulate a common gene expression program in establishing enviroment suitable for prostate cancer cell migration. Overall design: mRNA profiles of luciferase knockdown (WT), ETS1 knockdown, and U0126 treated DU145 cells were generated using deep sequencing, in triplicate, using Illumina HiSeq. Knockdowns were stable shRNA expression from a lentiviral construct selected with puromycin.
Interaction with ZMYND11 mediates opposing roles of Ras-responsive transcription factors ETS1 and ETS2.
No sample metadata fields
View SamplesLoss of E2F transcription factos alters metastatic capacity of MMTV-PyMT tumors.
Histological subtypes of mouse mammary tumors reveal conserved relationships to human cancers.
Disease
View SamplesWe used microarrays to futher characterize the effects of T58A mutation in Myc on mammary tumorigenesis.
A mouse model with T58A mutations in Myc reduces the dependence on KRas mutations and has similarities to claudin-low human breast cancer.
Specimen part
View SamplesDevelopment of LNA gapmers, antisense oligonucleotides used for efficient inhibition of target RNA expression, is limited by non-target mediated hepatotoxicity issues. In the present study, we investigated hepatic transcription profiles of mice receiving non-toxic and toxic LNA gapmers after a single and repeat administration.
Comparison of hepatic transcription profiles of locked ribonucleic acid antisense oligonucleotides: evidence of distinct pathways contributing to non-target mediated toxicity in mice.
Sex, Specimen part
View SamplesAdvances in genomic signatures have begun to dissect breast cancer heterogeneity, and application of these signatures will allow the prediction of which pathways are important in tumor development. Here we used genomic signatures to predict involvement of specific E2F transcription factors in Myc-induced tumors. We genetically tested this prediction by interbreeding Myc transgenics with mice lacking various activator E2F alleles. Tumor latency decreased in the E2F1 mutant background and significantly increased in both the E2F2 and E2F3 mutants. Investigating the mechanism behind these changes revealed a reduction in apoptosis in the E2F1 knockout strain. E2F2 and E2F3 mutant backgrounds alleviated Myc effects on the mammary gland, reducing the susceptible tumor target population. Gene expression data from tumors revealed that the E2F2 knockout background resulted in fewer tumors with EMT, corresponding with a reduction in probability of Ras activation. In human breast cancer we found that a low probability of E2F2 pathway activation was associated with increased relapse-free survival time. Together these data illustrate the predictive utility of genomic signatures in deciphering the heterogeneity within breast cancer and illustrate the unique genetic requirements for individual E2Fs in mediating tumorigenesis in both mouse models and human breast cancer.
Prediction and genetic demonstration of a role for activator E2Fs in Myc-induced tumors.
Specimen part
View SamplesSTEAP4 is a plasma membrane metallo-reductase involved in the transport of iron and copper. Recently, STEAP4 was implicated in promoting insulin sensitivity by acting in white adipose tissue (WAT) to control the production of inflammatory cytokines such as IL-6. Indeed, the loss of STEAP4 expression in mice leads to increased production of inflammatory cytokines in visceral WAT and systemic insulin resistance. In this report, we demonstrate that in mouse liver STEAP4 is produced at significant levels and that STEAP4 transcription is induced by IL-6. We further demonstrate that the STEAP4 gene is a direct target of phosphorylated STAT3 in mouse liver. In addition, hepatic STEAP4 expression is regulated by feeding and fasting, and obesity leads to the induction of STEAP4 expression in the liver. Interestingly, the regulation of STEAP4 in both feeding and fasting and the obese state appears to require the transcription factor C/EBPalpha that may act in concert with STAT3 as they both bind to the proximal STEAP4 promoter in vivo. Taken together these data suggest the transcriptional regulation of hepatic STEAP4 may play a critical role in the response to nutritional and inflammatory stress and contribute to the protective effect of STEAP4 in vivo.
Regulation of hepatic six transmembrane epithelial antigen of prostate 4 (STEAP4) expression by STAT3 and CCAAT/enhancer-binding protein alpha.
Sex, Specimen part
View SamplesGermline BRCA1 or BRCA2 mutations (mtBRCA1 and mtBRCA2) dramatically increase risk for high-grade serous ovarian cancer (HGSOC), the most commonly diagnosed histotype. Other risk factors for this cancer, which originates primarily in the distal fallopian tube epithelium (FTE), implicate ovulation. To test whether mtBRCA1 or mtBRCA2 FTE cells respond differently to peri-ovulatory follicular fluid (FF) exposure than control patient FTE, gene expression profiles from primary FTE cultures were compared at baseline, 24h after FF exposure, and 24h after FF replacement with culture medium. Hierarchical clustering revealed both FF exposure and BRCA mutation status affect gene expression, with BRCA1 mutation having the greatest impact. Analysis revealed increased NFB and EGFR signaling at baseline, with increased interferon signaling after recovery from FF exposure in mtBRCA1 samples. Inhibition of EGFR signaling and ISGylation by increased BRCA1 expression was verified in an immortalized FTE cell line, OE-E6/E7, stably transfected with BRCA1. Suppression of ISG15 and ISGylated protein levels by BRCA1 expression was found to be mediated by decreased NFB signaling and was transiently suppressed by FF exposure. This study demonstrates increased NFB signaling associated with decreased BRCA1 expression resulting in increased ISG15 and ISGylation following FF exposure, which could represent potential targets for chemoprevention.
BRCA1 Mutation Status and Follicular Fluid Exposure Alters NFκB Signaling and ISGylation in Human Fallopian Tube Epithelial Cells.
Specimen part, Time
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