Purpose: Myxopapillary ependymoma (MPE) is a distinct histological variant of ependymoma arising commonly in the spinal cord. Despite an overall favorable prognosis, distant metastases, subarachnoid dissemination, and late recurrences have been reported. Currently the only effective treatment for MPE is gross-total resection. We characterized the genomic and transcriptional landscape of spinal ependymomas in an effort to delineate the genetic basis of this disease and identify new leads for therapy.
Spinal Myxopapillary Ependymomas Demonstrate a Warburg Phenotype.
Sex, Specimen part, Disease stage
View SamplesWe have demonstrated that allergic airway inflammation (induced by an ovalbumin sensitization and aerosol challenge protocol) decreases lung bacterial burden following lung infection with Klebsiella pneumoniae. The goals of this study are to indentify novel targets that are expressed during allergic airway inflammation in this model that contribute to enhanced lung bacterial immunity. Overall design: We isolated total RNA from the lungs of 4 groups of mice at both 0 hours (pre-infection) and 6 hours post-infection. WT and STAT6KO (BALB/c) mice were intraperitoneally sensitzed with alum or ovalbumin (OVA)-alum on day -18. Alum injected mice were not subsequently exposed to OVA aerosol. OVA-alum injected mice underwent aerosol sensitization on days -4, -3, -2, and -1. On day 0, four groups of mice were harvested (pre-infection). These included WT-ALUM, WT-OVA, STAT6KO-ALUM, and STAT6KO-OVA. On day 0, four groups of mice were infected with 10^4cfu of Klebsiella and then lungs were removed at 6 hours post-infection. These groups included WT-ALUM-KP, WT-OVA-KP, STAT6KO-ALUM-KP, and STAT6KO-OVA-KP. The right lung was removed for RNA isolation. Each group contained between 4 and 5 mice.
Allergic airway inflammation decreases lung bacterial burden following acute Klebsiella pneumoniae infection in a neutrophil- and CCL8-dependent manner.
No sample metadata fields
View SamplesGene expression profiles of human cell (THP-1) lines exposed to a novel Daboiatoxin (DbTx) isolated from Daboia russelli russelli, and specific cytokines and inflammatory pathways involved in acute infection caused by Burkholderia pseudomallei.
Gene Microarray Analyses of Daboia russelli russelli Daboiatoxin Treatment of THP-1 Human Macrophages Infected with Burkholderia pseudomallei.
No sample metadata fields
View SamplesThe Ras family of GTPases play an important role in signaling nodes downstream to T cell receptor and CD28 activation, potentially lowering the threshold for TCR activation by autoantigens. Somatic mutation in NRAS or KRAS may cause a rare autoimmune disorder coupled with abnormal expansion of lymphocytes. T cells from Rheumatoid Arthritis (RA) patients show excessive activation of Ras/MEK/ERK pathway. The small molecule farnesylthiosalicylic acid (FTS) interferes with the interaction between Ras GTPases and their prenyl-binding chaperones to inhibit proper plasma membrane localization. In the present study, we tested the therapeutic and immunomodulatory effects of FTS and its derivative 5-fluoro-FTS (F-FTS) in the rat adjuvant-induced arthritis model (AIA). We show that AIA severity was significantly reduced by oral FTS and F-FTS treatment compared to vehicle control treatment. FTS was as effective as the mainstay anti-rheumatic drug methotrexate, and combining the two drugs significantly increased efficacy compared to each drug alone. We also discovered that FTS therapy inhibited both the CFA-driven in vivo induction of Th17 and IL-17/IFN-g producing double positive as well as the upregulation of serum levels of the Th17-associated cytokines IL-17A and IL-22. By gene microarray analysis of effector CD4+ T cells from CFA-immunized rats, re-stimulated in vitro with the mycobacterium tuberculosis heat-shock protein 65 (Bhsp65), we determined that FTS abrogated the Bhsp65-induced transcription of a large list of genes (e.g. Il17a/f, Il22, Ifng, Csf2, Lta, and Il1a). The functional enrichment bioinformatics analysis showed significant overlap with predefined gene sets related to inflammation, immune system processes and autoimmunity. In Conclusions, FTS and F-FTS display broad immunomodulatory effects in AIA with inhibition of the Th17-type response to a dominant arthritogenic antigen. Hence, targeting Ras signal-transduction cascade is a potential novel therapeutic approach for RA.
Ras Signaling Inhibitors Attenuate Disease in Adjuvant-Induced Arthritis <i>via</i> Targeting Pathogenic Antigen-Specific Th17-Type Cells.
Specimen part, Treatment
View SamplesDespite RNAi-based screens to uncover genes controlling embryonic stem cell (ESC) identity, the pluripotency network remains poorly characterized, as does the precise molecular mechanisms underlying the balance between self-renewal and differentiation. Here we carried out a systematic meta-analysis of published gene expression data to rank-order genes based on their likelihood of regulating ESC identity. Not only did our analysis correctly rank known pluripotency-associated genes atop the list, but it also helped unearth many novel determinants of ESC identity including several components of functionally distinct complexes, as determined using RNAi. We focus on our top-hit Nucleolin, and characterize its mechanistic role in the maintenance of ESC homeostasis by shielding from differentiation-inducing redox imbalance-induced oxidative stress. Notably, we identify a conceptually novel mechanism involving a Nucleolin-dependent bistable switch regulating the homeostatic balance between self-renewal and differentiation in ESCs. Our gene ranks represent a rich and valuable resource for uncovering novel ESC regulators.
Integrative framework for identification of key cell identity genes uncovers determinants of ES cell identity and homeostasis.
Cell line
View SamplesWe found that RANKL, expressed by cancer cells or derived from exogenous sources, consistently induced human prostate, breast, kidney, lung and liver cancer cells to colonize or metastasize to bone in an animal model of cancer bone metastasis. RANK-mediated signaling established a premetastatic niche through a forward feedback loop by inducing RANKL and c-Met expression and downstream signaling via upregulation of master regulator transcription factors regulating EMT (Twist1, Slug, Zeb1, Zeb2), stem cells (Sox2, Myc, Oct3/4 and Nanog), neuroendocrine cells (Sox 9, HIF-1 and FoxA2) and osteomimicry (c-Myc/Max, Sox2, Sox9, HIF1 and Runx2). Abrogating RANK or its downstream signaling network, c-Myc/Max or c-Met, abolished PCa skeletal metastasis in mice. We observed that a small number of RANKL-expressing PCa cells can initiate bone and soft tissue metastases by recruiting non-tumorigenic or bystander PCa or host cells from the circulation or at metastatic sites to co-colonize bone. The recruited bystander PCa cells assume the phenotypes of RANKL-expressing PCa cells by expressing increased c-Met, phosphorylated c-Met and RANKL. RANKL expression at a single cell level in primary PCa tissues predicted disease-specific survival, reflecting the significant role of RANKL-RANK signaling in the development of lethal bone metastasis.
RANK- and c-Met-mediated signal network promotes prostate cancer metastatic colonization.
Specimen part, Cell line
View SamplesThe generation of induced pluripotent stem cells (iPSCs) and the direct conversion approach provide an invaluable resource of cells for disease modeling, drug screening, and patient-specific cell-based therapy. However, while iPSCs are stable and resemble ESCs in their transcriptome, methylome and function, the vast majority of the directly converted cells represent an incomplete reprogramming state as evident by their aberrant transcriptome and transgene dependency. This raises the question of whether complete and stable nuclear reprogramming can be achieved only in pluripotent cells. Here we demonstrate the generation of stable and fully functional induced trophoblast stem cells (iTSCs) by transient expression of Gata3, Tfap2c and Eomes. Similarly to iPSCs, iTSCs underwent a complete and stable reprogramming process as assessed by transcriptome and methylome analyses and functional assays such as the formation of hemorrhagic lesion and placenta contribution. Careful examination of the conversion process indicated that the cells did not go through a transient pluripotent state. These results suggest that complete nuclear reprograming can be attained in non-pluripotent cells. Overall design: Technical duplicates of 10 samples
Extensive Nuclear Reprogramming Underlies Lineage Conversion into Functional Trophoblast Stem-like Cells.
No sample metadata fields
View SamplesNot all patients with nerve injury develop neuropathic pain. The extent of nerve damage and age at the time of injury are two of the few risk factors identified to date. In addition, preclinical studies show that neuropathic pain variance is heritable. To define such factors further, we performed a large-scale gene profiling experiment which plotted global expression changes in the rat dorsal root ganglion in three peripheral neuropathic pain models. This resulted in the discovery that the potassium channel alpha subunit KCNS1, involved in neuronal excitability, is constitutively expressed in sensory neurons and markedly downregulated following nerve injury. KCNS1 was then characterized by an unbiased network analysis as a putative pain gene, a result confirmed by single nucleotide polymorphism association studies in humans. A common amino acid changing allele, the 'valine risk allele', was significantly associated with higher pain scores in five of six independent patient cohorts assayed (total of 1359 subjects). Risk allele prevalence is high, with 18-22% of the population homozygous, and an additional 50% heterozygous. At lower levels of nerve damage (lumbar back pain with disc herniation) association with greater pain outcome in homozygote patients is P = 0.003, increasing to P = 0.0001 for higher levels of nerve injury (limb amputation). The combined P-value for pain association in all six cohorts tested is 1.14 E-08. The risk profile of this marker is additive: two copies confer the most, one intermediate and none the least risk. Relative degrees of enhanced risk vary between cohorts, but for patients with lumbar back pain, they range between 2- and 3-fold. Although work still remains to define the potential role of this protein in the pathogenic process, here we present the KCNS1 allele rs734784 as one of the first prognostic indicators of chronic pain risk. Screening for this allele could help define those individuals prone to a transition to persistent pain, and thus requiring therapeutic strategies or lifestyle changes that minimize nerve injury.
Multiple chronic pain states are associated with a common amino acid-changing allele in KCNS1.
Age
View SamplesWe used microarray-based expression genomics in 25 inbred mouse strains to identify dorsal root ganglion (DRG)-expressed genetic contributors to mechanical allodynia a prominent symptom of chronic pain.
The nicotinic α6 subunit gene determines variability in chronic pain sensitivity via cross-inhibition of P2X2/3 receptors.
Sex, Age, Specimen part
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