Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is an aggressive hematological. We used transcriptomic analysis to investigate LXR pathway, and cholesterol metabolism in leukemic cells. Malignancy with a poor prognosis that derives from plasmacytoid dendritic cells (PDC). No consensus for optimal treatment modalities is available today and the full characterization of this leukemia is still emerging. We identified here a BPDCN-specific transcriptomic profile when compared to those of acute myeloid leukemia (AML) and T-acute lymphoblastic leukemia (T-ALL), as well as the transcriptomic signature of primary PDC. This BPDCN gene signature identified a dysregulation of genes involved in cholesterol homeostasis, some of them being liver X receptor (LXR) target genes. LXR agonist treatment of primary BPDCN cells and BPDCN cell lines restored LXR target gene expression and increased cholesterol efflux via the upregulation of ATP Binding Cassette (ABC) transporters, ABCA1 and ABCG1. LXR agonist treatment was responsible for limiting BPDCN cell proliferation and inducing intrinsic apoptotic cell death. LXR activation in BPDCN cells was shown to interfere with three signaling pathways associated with leukemic cell survival, namely: NF-B activation, as well as Akt and STAT5 phosphorylation in response to the BPDCN growth/survival factor IL-3. These effects were increased by the stimulation of cholesterol efflux through a lipid acceptor, the apolipoprotein A1. In vivo experiments using a mouse model of BPDCN cell xenograft revealed a decrease of leukemic cell infiltration and BPDCN-induced cytopenia associated with an increased survival after LXR agonist treatment. This demonstrates that cholesterol homeostasis is modified in BPDCN and can be normalized by treatment with LXR agonists which can be proposed as a new therapeutic approach.
LXR agonist treatment of blastic plasmacytoid dendritic cell neoplasm restores cholesterol efflux and triggers apoptosis.
Specimen part, Disease, Disease stage
View SamplesAortic valve calcification is the most common form of valvular heart disease, but the mechanisms of calcific aortic valve disease (CAVD) are unknown. NOTCH1 mutations are associated with aortic valve malformations and adult-onset calcification in families with inherited disease. The Notch signaling pathway is critical for multiple cell differentiation processes, but its role in the development of CAVD is not well understood. The aim of this study was to investigate the molecular changes that occur with inhibition of Notch signaling in the aortic valve. Notch signaling pathway members are expressed in adult aortic valve cusps, and examination of diseased human aortic valves revealed decreased expression of NOTCH1 in areas of calcium deposition. To identify downstream mediators of Notch1, we examined gene expression changes that occur with chemical inhibition of Notch signaling in rat aortic valve interstitial cells (AVICs).
Inhibitory role of Notch1 in calcific aortic valve disease.
Specimen part
View SamplesSwiss-Webster female mice (Charles River Laboratories, Wilmington, MA) 5-6 weeks of age were infected intranasally with 5 LD50 of either WT or lpp mutant of Y. pestis CO92. Uninfected mice were used as controls. At either 12 or 48 h post infection (p.i.), 3 mice per group were euthanized and the lungs, livers, and spleens were harvested and homogenized in 1 ml of RNALater (Ambion/Applied Biosystems, Austin, TX) using 50-ml tissue homogenizers (Kendell, Mansfield, MA). RNA was isolated from the tissue homogenates and purified using RNAqueous (Ambion). After an overnight precipitation, the RNA was resuspended in 20 ul of diethylpyrocarbonate (DEPC)-treated water and hybridized to Affymetrix GeneChip Mouse Genome 430 2.0 arrays, performed by the Molecular Genomics Core at UTMB Galveston, Texas, per manufacture protocols. The arrays had 45,000 probe sets representing more than 39,000 transcripts derived from ~34,000 well-substantiated mouse genes. The experiments were performed in triplicate (biological replicates), generating a total of 45 arrays.
Comparative Analyses of Transcriptional Profiles in Mouse Organs Using a Pneumonic Plague Model after Infection with Wild-Type Yersinia pestis CO92 and Its Braun Lipoprotein Mutant.
Sex, Specimen part, Time
View SamplesGene expression profiling is a promising diagnostic and prognostic tool. Expression profiles are snap-shots of mRNA levels at time of extraction and they have been shown to be affected by tissue handling during sample collection. The effect of cold (room temperature) ischemia in the time interval between surgical removal of the specimen and freezing has been described in a number of studies. However, not much is known about the effect of warm (body temperature) ischemia during surgery.
Differential effect of surgical manipulation on gene expression in normal breast tissue and breast tumor tissue.
Sex, Specimen part, Disease, Subject
View SamplesMany reports show an association between the Pst system, the Pho regulon related genes and bacterial virulence. Our previous results showed that a functional Pst system is required for full virulence, resistance to serum, polymyxin B and acid shock. However, the interplay between the Pst system and virulence has an unknown molecular basis. To understand global APEC virulent strain responses to Pho regulon activation, we conducted transcriptome profiling experiments comparing the APEC chi7122 strain and its isogenic Pst mutant grown in rich phosphate medium using the Affymetrix GeneChip E. coli Genome 2.0 Array. The Affymetrix GeneChip E. coli Genome 2.0 Array contains the genome of the E. coli MG1655 and three pathogenic E. coli strain (EDL933, Sakai and CFT073) representing 20,366 genes. While comparing genes expression between Pst mutant and the wild type chi7122 strain, 471 genes are either up- (254) or down-regulated (217) of at least 1.5-fold, with a p-value inferior or equal to 0.05 and a false discovery rate of 2.71%.
Genome-wide transcriptional response of an avian pathogenic Escherichia coli (APEC) pst mutant.
No sample metadata fields
View SamplesSevere acute respiratory syndrome-associated coronavirus (SARS-CoV) infection causes an immune-mediated disease. We have recently shown that SARS-CoV-induced epithelial Calu-3 cytokines could exacerbate and dampen host inflammatory and T cell responses, respectively, through modulating the functions of macrophages and dendritic cells, thereby suggesting that not only are lung epithelial cells the primary cells of SARS-CoV infection, but they also involve in initiating and orchestrating the host innate and adaptive immunity. Comprehensive evaluation of the complex epithelial signaling to SARS-CoV is, thus, crucial for paving the way to better understand SARS pathogenesis and develop the innovative therapeutics against SARS. Here, based on the microarray-based functional genomics, we reported that 2B4 cells, a clonal derivative of Calu-3 cells, elicited a temporal and spatial activation of nuclear factor (NF)kappaB, activator protein (AP)-1 (ATF2/c-Jun), and interferon regulatory factor (IRF)-3/-7 at 12-, 24-, and 48-hrs post infection (p.i.), respectively, resulting in the activation of many antiviral genes, including interferon (IFN)-, -s, SARS-related inflammatory mediators, and various IFN-stimulated genes (ISGs). While elevated responses of IFN- and IFN-s were not detected until 48-hrs p.i., as a consequence of a delayed IRF-3/-7 activation, we showed, for the first time, that both types of IFNs exerted previously under-described non-redundant, complementary, and/or synergistic effects on the epithelial defense against SARS-CoV. Collectively, our results highlight the molecular mechanisms of the sequential activation of virus- and IFN-dependent signaling of lung epithelial cells against SARS-CoV and identify novel cellular targets for future studies, aiming at advancing strategies against SARS.
Dynamic innate immune responses of human bronchial epithelial cells to severe acute respiratory syndrome-associated coronavirus infection.
Cell line, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Increased H3K9me3 drives dedifferentiated phenotype via KLF6 repression in liposarcoma.
Cell line
View SamplesAberrant cell signaling can cause cancer and other diseases and is a focal point of drug research. A common approach is to infer signaling activity of pathways from gene expression. However, mapping gene expression to pathway components disregards the effect of post-translational modifications, and downstream signatures represent very specific experimental conditions. Here we present PROGENy, a method that overcomes both limitations by leveraging a large compendium of publicly available perturbation experiments to yield a common core of Pathway RespOnsive GENes. Unlike existing methods, PROGENy can (i) recover the effect of known driver mutations, (ii) provide or improve strong markers for drug indications, and (iii) distinguish between oncogenic and tumor suppressor pathways for patient survival. Collectively, these results show that PROGENy accurately infers pathway activity from gene expression. Overall design: HEK293?RAF1:ER cells were treated with different stimuli (4OHT, Ly29002, TNFa, TGF1b, IFNg) for different periods of time (1h, 4h).
Perturbation-response genes reveal signaling footprints in cancer gene expression.
Specimen part, Subject
View SamplesLittle is known about the epigenomics of liposarcoma (LPS). Here, we profiled the global expression of 9 epigenetic marks in well differentiated (WD) and dedifferentiated (DD) LPS from 151 patients and found increased H3K9me3 among DDLPS tumors. We performed ChIP-seqand gene expression profiling of patient derived cell lines to discover functionally significant regions of differential H3K9me3 enrichment between WDLPS and DDLPS associated with concomitant gene expression changes.
Increased H3K9me3 drives dedifferentiated phenotype via KLF6 repression in liposarcoma.
Cell line
View SamplesMalignant glioblastoma (GBM) is a highly aggressive brain tumor with a dismal prognosis and limited therapeutic options. Genomic profiling of GBM samples in the TCGA database has identified four molecular subtypes (Proneural, Neural, Classical and Mesenchymal), which may arise from different glioblastoma stem-like cell (GSC) populations. In the present study, we identify two GSC populations that produce GBM tumors by subcutaneous and intracranial injection with identical histological features. Gene expression analysis revealed that xenografts of GSCs grown as spheroid cultures had a Classical molecular subtype similar to that of bulk tumor cells. In contrast xenografts of GSCs grown as adherent cultures on laminin-coated plates expressed a Mesenchymal gene signature. Adherent GSC-derived xenografts had high STAT3 and ANGPTL4 expression as well as enrichment for stem cell markers, transcriptional networks and pro-angiogenic markers characteristic of the Mesenchymal subtype. Examination of clinical samples from GBM patients showed that STAT3 expression was directly correlated with ANGPTL4 expression, and that increased expression of these genes correlated with poor patient survival and performance. A pharmacological STAT3 inhibitor abrogated STAT3 binding to the ANGPTL4 promoter and exhibited anticancer activity in vivo. Taken together, we identified two distinct GSC populations that produce histologically identical tumors but with very different gene expression patterns, and a STAT3/ ANGPTL4 pathway in glioblastoma that may serve as a target for therapeutic intervention.
Molecular heterogeneity in a patient-derived glioblastoma xenoline is regulated by different cancer stem cell populations.
Specimen part
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