Analysis of five Notch signaling-dependent human T-ALL cell lines (ALLSIL, DND41, HPBALL, KOPTK1, TALL-1) treated with gamma-secretase inhibitor (GSI) to block Notch signaling. Samples include parental cells, cells rescued by retroviral transduction with ICN (a GSI-independent form of activated Notch1), and cells retrovirally transduced with c-Myc (an important downstream target of Notch1). Results allow segregation of bona fide Notch targets from other genes affected by gamma-secretase inhibition as well as from targets downstream of c-Myc.
High-level IGF1R expression is required for leukemia-initiating cell activity in T-ALL and is supported by Notch signaling.
Cell lineView Samples
In response to limited nitrogen and abundant carbon sources, diploid Saccharomyces cerevisiae strains undergo a filamentous transition in cell growth as part of pseudohyphal differentiation. Use of the disaccharide maltose as the principal carbon source, in contrast to the preferred nutrient monosaccharide glucose, has been shown to induce a hyper-filamentous growth phenotype in a strain deficient for GPA2 which codes for a Galpha protein component that interacts with the glucose-sensing receptor Gpr1p to regulate filamentous growth. In this report, we compare the global transcript and proteomic profiles of wild-type and Gpa2p deficient diploid yeast strains grown on both rich and nitrogen starved maltose media. We find that deletion of GPA2 results in significantly different transcript and protein profiles when switching from rich to nitrogen starvation media. The results are discussed with a focus on the genes associated with carbon utilization, or regulation thereof, and a model for the contribution of carbon sensing/metabolism-based signal transduction to pseudohyphal differentiation is proposed.
Transcript and proteomic analyses of wild-type and gpa2 mutant Saccharomyces cerevisiae strains suggest a role for glycolytic carbon source sensing in pseudohyphal differentiation.
No sample metadata fieldsView Samples
Statins reduce cardiovascular disease risk by lowering plasma low density lipoprotein (LDL)-cholesterol. To identify novel pathways that modulate statin response, we assessed the influence of simvastatin exposure on expression quantitative trait locus (eQTL) associations across the genome in 480 lymphoblastoid cell lines (LCLs). Cell lines were derived blood samples collected ant entry visit from participants in the Cholesterol and Pharmacogenomics (CAP) trial, who underwent a 6 week 40mg/day simvastatin trial. We identified 4590 cis-eQTLS that were independent of treatment status (FDR=1%) and six cis-eQTLS for which there was evidence of an interaction with treatment (FDR=20%). Genotypes and Phenotypes derived from these indivudals are available through dbGaP (Accession Number). eQTL results are available at: http://eqtl.uchicago.edu/cgi=bin/gbrowse/eqtl/
HNRNPA1 regulates HMGCR alternative splicing and modulates cellular cholesterol metabolism.
Sex, SubjectView Samples
INTRODUCTION. Fixation with formalin, a widely adopted procedure to preserve tissue samples, leads to extensive degradation of nucleic acids and thereby compromises procedures like microarray-based gene expression profiling. We hypothesized that RNA fragmentation is caused by activation of RNAses during the interval between formalin penetration and tissue fixation. To prevent RNAse activation, a series of tissue samples were kept under-vacuum at 4C until fixation and then fixed at 4C, for 24 hours, in formalin followed by 4 hours in ethanol 95%.
Formalin fixation at low temperature better preserves nucleic acid integrity.
Specimen partView Samples
We performed affymetrix gene expression profiling on mammary tumors from eight well-characterized genetically engineered Mouse (GEM) models of human breast cancer.
Integrated miRNA and mRNA expression profiling of mouse mammary tumor models identifies miRNA signatures associated with mammary tumor lineage.
Specimen partView Samples
KRAS mutations are present at a high frequency in human cancers. The development of therapies targeting mutated KRAS requires cellular and animal preclinical models. We exploited adeno-associated virus-mediated homologous recombination to insert the KRAS G12D allele in the genome of mouse somatic cells. Heterozygous mutant cells displayed a constitutively active Kras protein, marked morphologic changes, increased proliferation and motility but were not transformed. On the contrary, mouse cells in which we overexpressed the corresponding KRAS cDNA were readily transformed. The levels of Kras activation in knock-in cells were comparable with those present in human cancer cells carrying the corresponding mutation. KRAS-mutated cells were compared with their wild-type counterparts by gene expression profiling, leading to the definition of a "mutated KRAS-KI signature" of 345 genes. This signature was capable of classifying mouse and human cancers according to their KRAS mutational status, with an accuracy similar or better than published Ras signatures. The isogenic cells that we have developed recapitulate the oncogenic activation of Kras occurring in cancer and represent new models for studying Kras-mediated transformation. Our results have implications for the identification of human tumors in which the oncogenic KRAS transcriptional response is activated and suggest new strategies to build mouse models of tumor progression.
Knock-in of oncogenic Kras does not transform mouse somatic cells but triggers a transcriptional response that classifies human cancers.
No sample metadata fieldsView Samples
MicroRNAs (miRNAs) are a class of small RNA molecules that regulate expression of specific mRNA targets. They can be released from cells, often encapsulated within extracellular vesicles (EVs), and therefore have the potential to mediate intercellular communication. It has been suggested that certain miRNAs may be selectively exported, although the mechanism has yet to be identified. Manipulation of the miRNA content of EVs will be important for future therapeutic applications. We therefore wished to assess which endogenous miRNAs are enriched in EVs and how effectively an overexpressed miRNA would be exported. Small RNA libraries from HEK293T cells and vesicles before or after transfection with a vector for miR-146 overexpression were analysed by deep sequencing. A subset of miRNAs was found to be enriched in EVs. The global expression data provided by deep sequencing confirms that specific miRNAs are enriched in EVs released by HEK293T cells. Overall design: Cells were transfected with a plasmid to direct overexpression of miR-146a. Extracellular vesicles were isolated by ultracentrifugation from untreated and transfected cells. RNA was isolated from one sample each of untreated and transfected cells and vesicles.Small RNA libraries were prepared for sequencing.
Selective extracellular vesicle-mediated export of an overlapping set of microRNAs from multiple cell types.
Specimen part, SubjectView Samples
This SuperSeries is composed of the SubSeries listed below.
Suboptimal evolutionary novel environments promote singular altered gravity responses of transcriptome during Drosophila metamorphosis.
Sex, AgeView Samples