Predicting liver injury after exposure to toxic industrial chemicals is complicated by the large number of potential environmental contaminants, mixtures, and exposure dose and route scenarios. Identifying indicators of end organ injury can complement exposure-based assays and improve predictive power. A multiplexed approach was used to experimentally evaluate a panel of 67 genes predicted to be fibrogenic by computationally mining DrugMatrix, a publicly available repository of gene microarray data. Five-day oral gavage studies in male Sprague-Dawley rats dosed with varying concentrations of three fibrogenic compounds (allyl alcohol, carbon tetrachloride, and 4,4-methylenedianiline) and two non-fibrogenic compounds (bromobenzene and dexamethasone) were conducted. Fibrosis was definitively diagnosed by histopathology. Transcriptomics data matched the predictions made using the DrugMatrix data with greater than 90% accuracy. Microarray data were verified using a 67-plex panel Bioplex assay, confirming that the 67-plex panel constituted a biomolecular signature of hepatic fibrosis (Figure). Necrosis and inflammatory infiltration were comorbid with fibrosis. Interaction analysis identified 24 genes specific for the fibrosis phenotype. The protein product of the gene most strongly correlated with the fibrosis phenotype (Pcolce) was dose-dependently elevated in plasma from animals administered fibrogenic chemicals (p<0.05). PCOLCE is a novel biomarker candidate of fibrotic injury. These results support the development of gene panels for liver injury and may suggest bridging biomarkers for molecular mediators linked to histopathology.
Gene Expression Patterns Associated With Histopathology in Toxic Liver Fibrosis.
Sex, Specimen part
View SamplesMicroarray is widely used to monitor gene expression changes in breast cancer. The transcriptomic changes in breast cancer is commonly occured during the transition of normal cells to cancerous cells. This is the first study on gene expression profiling of multi ethnic of Malaysian breast cancer patients (Malays, Chinese and Indian). We aim to identify differentially expressed genes between tumors and normal tissues. We have identified a set of 33 significant differentially expressed genes in the tumor vs. normal group at p<0.001.
Gene expression patterns distinguish breast carcinomas from normal breast tissues: the Malaysian context.
Specimen part, Disease stage, Race
View SamplesImmunodeficient mouse models have been valuable for studies of human hematopoiesis, but high-fidelity recapitulation of erythropoiesis in most xenograft recipients remains elusive. Recently developed immunodeficient and Kit mutant mice, however, have provided a suitable background to achieve higher-level human erythropoiesis after long-term hematopoietic engraftment. While there has been some characterization of human erythropoiesis in these models, a comprehensive analysis of various developmental stages has not yet been reported. Here, we have utilized cell surface phenotypes, morphologic analyses, and molecular studies to fully characterize human erythropoiesis from multiple developmental stages in immunodeficient and Kit mutant mouse models following long-term hematopoietic stem and progenitor cell engraftment. We show that human erythropoiesis in such models demonstrates complete maturation and enucleation, as well as developmentally appropriate globin gene expression. These results provide a framework for future studies to utilize this model system for interrogating disorders affecting human erythropoiesis and for developing improved therapeutic approaches. Overall design: (mRNA-seq) RNA-seq of human CD235a+ cells isolated 14-16 weeks post-implantation from mouse bone marrow were performed for three biological replicates each of mice xenograted with adult bone marrow-derived human CD34+ cells and cord blood-derived CD34+ cells.
Developmentally-faithful and effective human erythropoiesis in immunodeficient and Kit mutant mice.
Specimen part, Subject
View SamplesLuminal breast cancers express estrogen (ER) and progesterone (PR) receptors, and respond to endocrine therapies. However, some ER+PR+ tumors display intrinsic or acquired resistance, possibly related to PR. Two PR isoforms, PR-A and PR-B, regulate distinct gene subsets that may differentially influence tumor fate. A high PR-A:PR-B ratio is associated with poor prognosis and tamoxifen resistance. We speculate that excessive PR-A marks tumors that will relapse early. Here we address mechanisms by which PR-A regulate transcription, focusing on SUMOylation. We use receptor mutants and synthetic promoter/reporters to show that SUMOylation deficiency or the deSUMOylase SENP1 enhance transcription by PR-A, independent of the receptors dimerization interface or DNA binding domain. De-SUMOylation exposes the agonist properties of the antiprogestin RU486. Thus, on synthetic promoters, SUMOylation functions as an independent brake on transcription by PR-A. What about PR-A SUMOylation of endogenous human breast cancer genes? To study these, we used gene expression profiling. Surprisingly, PR-A SUMOylation influences progestin target genes differentially, with some upregulated, others downregulated, and others unaffected. Hormone-independent gene regulation is also PR-A SUMOylation dependent. Several SUMOylated genes were analyzed in clinical breast cancer database. In sum, we show that SUMOylation does not simply repress PR-A. Rather, it regulates PR-A activity in a target selective manner including genes associated with poor prognosis, shortened survival, and metastasis.
SUMOylation Regulates Transcription by the Progesterone Receptor A Isoform in a Target Gene Selective Manner.
Specimen part, Treatment
View SamplesInvestigations on the fundamental of malaria parasite biology, such as invasion, growth cycle, metabolism and cell signalling have uncovered a number of potential antimalarial drug targets, including choline kinase, a key enzyme involved in the synthesis of phosphatidylcholine, an important component in parasite membrane compartment.
Effect of choline kinase inhibitor hexadecyltrimethylammonium bromide on Plasmodium falciparum gene expression.
Treatment
View SamplesEndogenous pancreatic multipotent progenitors (PMPs) are ideal candidates for regenerative approaches to compensate for b-cell loss since their b-cell–producing capacities as well as strategic location would eliminate unnecessary invasive manipulations. However, little is known about the status and potentials of PMPs under diabetic conditions. Here we show that b-cell metabolic stress and hyperglycemia enhance the proliferation capacities of adult PMP cells and bias their production of progeny toward b-cells in mouse and human. These effects are dynamic and correlate with functional b-cell regeneration when conditions allow. Overall design: Insulin-positive Glut2-low cell population of adult pancreatic tissue is enriched for PMP cells. Streptozocin (STZ) can enter beta-cells via Glut2 , induce cell death and consequently diabetes. Insulin-positive cells from two groups (STZ-injected experiment and vehicle-injected control, n=3/group) of MIP-GFP transgenic male mice were sorted to Glut2-low (Glut2L) and Glut2-high (Glut2H) by FACS. Total RNA from these samples were extracted for transcriptome analysis.
Diabetes enhances the proliferation of adult pancreatic multipotent progenitor cells and biases their differentiation to more β-cell production.
No sample metadata fields
View SamplesAlthough the locations of promoters and enhancers have been identified in several cell types, we have yet limited information on their connectivity. We developed HiCap, which combines Hi-C with promoter sequence capture, to enable genome-wide identification of regulatory interactions with single-enhancer resolution. HiCap analyses of mouse embryonic stem cells (mESC) identified promoter-enhancer interactions predictive of gene expression change upon perturbation, opening up for genomic analyses of long-range gene regulation. Overall design: HiCap was designed by combining Hi-C with with sequence capture (for all promoters) and carried out in mouse embryonic stem cells (mESC)
Genome-wide mapping of promoter-anchored interactions with close to single-enhancer resolution.
No sample metadata fields
View SamplesWe tested the effects of the antioxidant NAC (N-Acetyl-Cysteine) on gene expression in Nkx3.1-deficient mouse prostate.
Antioxidant treatment promotes prostate epithelial proliferation in Nkx3.1 mutant mice.
Age, Specimen part
View SamplesBackground: To date, few studies have systematically characterized microarray gene expression signal performance with degraded RNA from formalin-fixed paraffin-embedded (FFPE) specimens in comparison to intact RNA from unfixed fresh-frozen (FF) specimens.
Quantitative expression profiling in formalin-fixed paraffin-embedded samples by affymetrix microarrays.
Specimen part, Subject
View SamplesDifferent fusion oncogenes in acute myeloid leukemia (AML) have distinct clinical and laboratory features suggesting different modes of malignant transformation. Here we compare the in vitro effects of representatives of major groups of AML fusion oncogenes on primary human CD34+ cells.
In vitro transformation of primary human CD34+ cells by AML fusion oncogenes: early gene expression profiling reveals possible drug target in AML.
Specimen part
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