Valproic acid (VA) is a small-chain branched fatty acid, widely used as anticonvulsant, and mood stabilizer to treat psychiatric illness. Valproic acid is also known to inhibit the histone deacetylases (HDACs), which makes it as a potent antitumor agent in alone or in combination with other cytotoxic drugs. Beside its conventional activities, valproic acid reported to have much broader, complicated effects and affect many complex physiological processes. However the molecular mechanisms of valproic acid are unclear.
Combined Transcriptomics and Chemical-Genetics Reveal Molecular Mode of Action of Valproic acid, an Anticancer Molecule using Budding Yeast Model.
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View SamplesWe aimed to predict obesity risk with genetic data, specifically, obesity-associated gene expression profiles. Genetic risk score was computed. The genetic risk score was significantly correlated with BMI when an optimization algorithm was used. Linear regression and built support vector machine models predicted obesity risk using gene expression profiles and the genetic risk score with a new mathematical method.
A computational framework for predicting obesity risk based on optimizing and integrating genetic risk score and gene expression profiles.
Specimen part
View SamplesTo identify genes that mediate altered communication between fat body and peripheral tissues, we report the gene expression changes in Drosophila third instar larval fat bodies with or without constitutively-active Toll (Toll10b) to activate innate immune signaling, myristoylated Akt (myrAkt) to activate insulin signaling, or both transgenes to bypass the block from Toll signaling to the upstream part of the insulin signaling pathway Overall design: Comparison of RFP/GFP (Control), Toll10b/GFP (Toll10b), RFP/myrAkt (myrAkt), and Toll10b/myrAkt (Toll10b + myrAkt)
The Toll Signaling Pathway Targets the Insulin-like Peptide Dilp6 to Inhibit Growth in Drosophila.
Specimen part, Cell line, Subject
View SamplesThe activation of TLR-MyD88 (Toll like receptor- Myeloid differentiation factor 88) signaling within T cells functions as a potent costimulatory signal that boosts antitumor and antiviral responses. However, the molecular mechanisms underlying the costimulatory processes are poorly understood. We compared microarray gene analysis data between TLR1-TLR2 stimulated and unstimulated T cell receptor transgenic pmel and MyD88-/-pmel CD8+ T cells and identified changes in the expression levels of several TNF family members. In particular, TLR-stimulation increased 4-1BB levels in pmel but not in MyD88-/-pmel T cells. A link between 4-1BB and TLR1-TLR2 signaling in CD8+ T cells was highlighted by in fact that 4-1BB-/- T cells exhibited suboptimal responses to TLR1-TLR2 agonist, but responded normally to CD28 or OX40 costimulation. Moreover, blocking 4-1BB signaling with antibodies also hindered the costimulatory effects of the TLR1-TLR2 agonist. The elevated levels of 4-1BB transcripts in TLR1-TLR2stimulated cells were not due to increased mRNA stability nor increased histone activation but instead were associated with increased binding of p65 and c-Jun to two distinct 4-1BB promoter sites. Combining TLR1-TLR2 ligand with an agonistic anti-4-1BB antibody enhanced the antitumor activity in mice with established melanoma tumors. These studies reveal that the costimulatory effects of TLR1-TLR2 signaling in CD8+ T cells are in part mediated by 4-1BB and are important for mounting an effective antitumor immune response.
Cross-talk between 4-1BB and TLR1-TLR2 Signaling in CD8+ T Cells Regulates TLR2's Costimulatory Effects.
Specimen part
View SamplesUnderstanding the identity of lineage-specific cells arising during manipulations of stem cells is necessary for developing their potential applications. For instance, replacement of crucial functions in organ failure by transplantation of suitable stem-cell-derived cells will be applicable to numerous disorders, but requires insights into the origin, function and fate of specific cell populations. We studied mechanisms by which the identity of differentiated cells arising from stem cells could be verified in the context of natural liver-specific stem cells and whether such differentiated cells could be effective for supporting the liver following cell therapy in a mouse model of drug-induced acute liver failure. By comparing the identity of naturally occurring fetal human liver stem cells, we found that cells arising in cultures of human embryonic stem cells (hESCs) recapitulated an early fetal stage of liver cells, which was characterized by conjoint meso-endoderm properties. Despite this fetal stage, hESC-derived cells could provide liver support with appropriate metabolic and ammonia-fixation functions, as well as cytoprotection, such that mice were rescued from acute liver failure. Therefore, spontaneous or induced differentiation of human embryonic stem cells along the hepatic endoderm will require transition through fetal-like stages. This offers opportunities to prospectively identify whether suitable cells have been generated through manipulation of stem cells for cell therapy and other applications.
Spontaneous origin from human embryonic stem cells of liver cells displaying conjoint meso-endodermal phenotype with hepatic functions.
Specimen part
View SamplesCSL is a key transcription factor, mostly acting as a repressor. While known as main effector of Notch signaling, it can also play Notch-independent functions. Despite the wide interest in CSL, the mechanisms responsible for its own regulation have been little studied. We recently showed that CSL down-modulation in human dermal fibroblasts (HDFs) leads to conversion into cancer associated fibroblasts, which promote keratinocyte tumor development. We show here that levels of CSL gene transcription differ among HDF strains derived from many different individuals, with negative correlation with genes involved in DNA damage/repair. CSL expression in all tested strains is negatively regulated by stress / DNA damaging insults caused by UVA, Reactive Oxygen Species (ROS), smoke extract and doxorubicin treatment. p53, a key effector of the DNA damage response, functions as common negative regulator of CSL gene transcription, through both suppression of CSL promoter activity and, indirectly, through increased p21 expression. CSL was previously shown to bind p53 suppressing its activity. The present findings indicate that p53, in turn, decreases CSL expression, which can serve to enhance p53 activity in the acute response of cells to DNA damaging cancer-threatening conditions. Overall design: RNA sequencing of 46 human foreskin fibroblasts
Negative control of CSL gene transcription by stress/DNA damage response and p53.
No sample metadata fields
View SamplesIdiopathic pulmonary fibrosis (IPF) and non-specific interstitial pneumonia (NSIP) are the 2 most common forms of idiopathic interstitial pneumonia. Response to therapy and prognosis are remarkably different. The clinical-radiographic distinction between IPF and NSIP may be challenging. We sought to investigate the gene expression profile of IPF vs. NSIP
Comprehensive gene expression profiling identifies distinct and overlapping transcriptional profiles in non-specific interstitial pneumonia and idiopathic pulmonary fibrosis.
Specimen part, Disease, Disease stage
View SamplesBoth cigarette smoking and obesity have been implicated in increased risk of clear cell renal cell carcinoma (ccRCC); however, there are limited data regarding the molecular mechanisms that underlie these associations. We used a multi-stage design to identify and validate specific molecular targets that are associated with smoking or obesity-related ccRCC.
ANKS1B is a smoking-related molecular alteration in clear cell renal cell carcinoma.
Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Feasibility of developing reliable gene expression modules from FFPE derived RNA profiled on Affymetrix arrays.
Specimen part
View SamplesThe reliability of differential expression analysis on FFPE expression profiles from Affymetrix arrays is questionable, due to the wide range of percent-present values reported in studies which profiled FFPE samples on Affymetrix arrays. Moreover the validity of externally defined gene-modules in FFPE microarray expression profiles is unknown. Using eight breast cancer tumors with available frozen and FFPE samples, five sample-matched data sets were generated from different combination of Affymetrix arrays, amplification-and-labeling kit and sample preservation method. The reliability of differential expression analysis was investigated by developing de novo ER/HER2 pathway gene-modules from matched data sets and validating it on external data set using ROC analysis. Spearman's rank correlation coefficient of module scores between matched FFPE-frozen expression profiles was used to measure reliability of externally defined gene-modules in FFPE expression profiles. Independent of array/amplification-kit/sample preservation method used, de novo ER/HER2 gene-modules derived from all matching data sets showed similar prediction performance during independent validation (AUC range; ER: 0.92-0.95, HER2: 0.88-0.91), except for de novo HER2 gene-module derived from FFPE data set with 3'IVT kit (AUC: 0.67-0.72). Further not all gene-module based biological signals present in frozen expression profiles can be recovered from matching FFPE microarray expression profiles using the currently available FFPE specific sample preparation kits. The gene-module based biological signal extracted from FFPE RNA, using microarrays, may not be as reliable as that from their frozen counterpart, if the sample preparation protocol used with FFPE RNA failed to recover relevant genes involved in the biological signal.
Feasibility of developing reliable gene expression modules from FFPE derived RNA profiled on Affymetrix arrays.
Specimen part
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