Gene expression profiles in HepG2 cells exposed to atorvastatin
ABSTRACT: In the exon array data set, gene level analysis was performed on HepG2 cells exposed to atorvastatin. No genes were found to be statistically significantly differentially expressed upon atorvastatin treatment. 3 control and 3 atorvastatin treated HepG2 samples were analysed. Genes with an FDR≤5% after Benjamini-Hochberg correction was considered as differentially expressed.
Project description:Alternative mRNA splicing is a major mechanism for gene regulation and transcriptome diversity. Despite the extent of the phenomenon, the regulation and specificity of the splicing machinery are only partially understood. Adenosine-to-inosine (A-to-I) RNA editing of pre-mRNA by ADAR enzymes has been linked to splicing regulation in several cases. Here we used bioinformatics approaches, RNA-seq and exon-specific microarray of ADAR knockdown cells to globally examine how ADAR and its A-to-I RNA editing activity influence alternative mRNA splicing. Although A-to-I RNA editing only rarely targets canonical splicing acceptor, donor, and branch sites, it was found to affect splicing regulatory elements (SREs) within exons. Cassette exons were found to be significantly enriched with A-to-I RNA editing sites compared with constitutive exons. RNA-seq and exon-specific microarray revealed that ADAR knockdown in hepatocarcinoma and myelogenous leukemia cell lines leads to global changes in gene expression, with hundreds of genes changing their splicing patterns in both cell lines. This global change in splicing pattern cannot be explained by putative editing sites alone. Genes showing significant changes in their splicing pattern are frequently involved in RNA processing and splicing activity. Analysis of recently published RNA-seq data from glioblastoma cell lines showed similar results. Our global analysis reveals that ADAR plays a major role in splicing regulation. Although direct editing of the splicing motifs does occur, we suggest it is not likely to be the primary mechanism for ADAR-mediated regulation of alternative splicing. Rather, this regulation is achieved by modulating trans-acting factors involved in the splicing machinery. HepG2 and K562 cell lines were stably transfected with plasmids containing siRNA designed to specifically knock down ADAR expression (ADAR KD). This in order to examine how ADAR affects alternative splicing globally.
Project description:MiR-142 is upregulated in neurons in HIV and SIV encephalitis. We have created stable clones of the BE(2)M17 human neuroblastoma cell line overexpressing miR-142. Gene expression in these miR-142-expressing clones was compared to stable clones transfected with control miR-null in order to identify miR-142 targets relevant to neuronal dysfunction in HIV encephalitis. RNA was extracted from 3 independent miR-142-expressing clones (6B, 6C, 6G) and 3 independent miR-null expressing clones (1A, 2A, 2B) for expression analysis. Partek genomics suite was used for data analysis. Genes that had fold change > -2.5 and p <0.001 were chosen for validation by RT-PCR
Project description:MicroRNAs are a group of non-coding small RNAs with lengths around 21~23nt and function as inhibitors to repress mRNA translation by targeting their 3' untranslated region. Recent research shows that microRNAs are involved in many biological processes such as cell growth, development and cancer, etc. Here, we introduce a novel artificial microRNA p-27-5p which can inhibit cell proliferation in breast cancer cell lines. This data shows the expression changes in breast cancer cell line T-47D with the effect of artificial miR-p-27-5p. 4 total samples were analyzed. We generated mimic/control paired samples with 2 repeats.
Project description:We analyzed a role of Brd2 protein in transcription and alternative splicing. 289 genes change alternative splicing after Brd2 knockdown and 1459 genes alter gene expression compared to cells treated with negative control siRNA. 6 samples (3 independent samples of cells treated with Brd2 siRNA, 3 samples of cells treated with negative control siRNA)
Project description:RNA extracted from CD4 cells was analyzed using affymetrix gene array chips.Data set includes analysis of RNA from DMSO or ATRA treated samples. ATRA induced the expression of a number of genes including LZTFL1. Retinoic acids, which are metabolites of vitamin A, have been shown to be involved in multiple T cell effector responses through their binding to the retinoic acid receptor, a ligand-activated transcription factor. Because the molecular mechanism of regulation by retinoic acid is still not fully uncovered, we investigated the gene expression profile of all-trans retinoic acid (ATRA)-treated human CD4(+) T cells. Leucine zipper transcription factor-like 1 (LZTFL1) was upregulated by ATRA in a dose- and time-dependent manner. The expression of LZTFL1 depended on both ATRA and TCR signaling. LZTFL1 accumulated in the plasma membrane compartment of human CD4(+) T cells, and, during immunological synapse formation, it transiently redistributed to the T cell and APC contact zone, indicating its role in T cell activation. Live-cell imaging demonstrates that at the initial stage of immunological synapse formation, LZTFL1 is concentrated at the APC contact site, and, during later stages, it relocates to the distal pole. Knockdown of LZTFL1 reduced the basal- and ATRA-induced levels of IL-5 in CD4(+) T cells, and overexpression of LZTFL1 enhanced the TCR-mediated NFAT signaling, suggesting that LZTFL1 is an important regulator of ATRA-induced T cell response. Together, these data indicate that LZTFL1 modulates T cell activation and IL-5 levels. CD4 cells were isolated from human PBMCs and primed with anti-CD3 and IL-2 in presence and absence of retinoic acid. Two days later RNA was extracted and analyzed.
Project description:Expression data from 22 human myotubes (7 healthy controls, 4 Dysferlinopathy (DYSF), 4 Caveolinopathy 3 (CAV3), 4 Facioscapulohumeral muscular dystrophy(FSHD) and 3 Four and a half LIM 1 protein deficiency FHL1).cDNA microarray data showed that cyclin A1 levels are specifically elevated in FSHD vs. other muscular disorders such as CAV3, DYSF, FHL1 and healthy control. Data could be confirmed with RT-PCR and Western blot analysis showing up-regulated levels of cyclin A1 also on the protein level. Comparison of gene expression among 4 different muscular dystrophies and helathy controls. Looking for genes expression specifically changed (down/upregulated) in FSHD. In these data sheet we include expression data obtained for human cells lines derived from human V.lateralis muscle, shown as mean value. From 59 different expressed genes, Cyclin A1 was selected as a highly overexpressed (28 fold) gene in FSHD if compared to DYSF, CAV3, FHL1 and healyhy controls. Expression data from 22 human myotubes (7 healthy controls, 4 Dysferlinopathy (DYSF), 4 Caveolinopathy 3 (CAV3), 4 Facioscapulohumeral muscular dystrophy(FSHD) and 3 Four and a half LIM 1 protein deficiency FHL1)
Project description:ERG overexpression is the most frequent molecular alteration in prostate cancer. We analyzed different stages of prostate cancer to identify genes that were coexpressed with ERG overexpression. In primary prostate tumors, it was shown that TDRD1 expression was the strongest correlated gene with ERG overexpression and we suggest TDRD1 as a direct ERG target gene. 48 Prostate cancer samples from radical prostatectomies were included in this study. These samples contained more than 70% cancer and less than 30% stromal tissue. Each sample was analyzed once.
Project description:While blood transcriptional profiling has improved diagnosis and understanding of disease pathogenesis of adult tuberculosis (TB), no studies applying gene expression profiling of children with TB have been described so far. In this study, we have compared whole blood gene expression in childhood TB patients, as well as in healthy latently infected (LTBI) and uninfected (HC) children in a cohort of Warao Amerindians in the Delta Amacuro in Venezuela. We identified a 116-gene signature set by means of random forest analysis that showed an average prediction error of 11% for TB vs. LTBI and for TB vs. LTBI vs. HC in our dataset. Furthermore, a minimal set of only 9 genes showed a significant predictive value for all previously published adult studies using whole blood gene expression, with average prediction errors between 17% and 23%. Additionally, a minimal gene set of 42 genes with a comparable predictive value to the 116-gene set in both our dataset and the previously published literature cohorts for the comparsion of TB vs. LTBI vs. HC was identified. In order to identify a robust representative gene set that would hold stand among different ethnic populations, we selected ten genes that were highly discriminative between TB, LTBI and HC in all literature datasets as well as in our dataset. Functional annotation of these ten genes highlights a possible role for genes involved in calcium signaling and calcium metabolism as biomarkers for active TB. These ten genes were validated by quantitative real-time polymerase chain reaction in an additional cohort of 54 Warao Amerindian children with LTBI, HC and non-TB pneumonia. Decision tree analysis indicated that five of the ten genes were sufficient to diagnose 78% of the TB cases correctly with 100% specificity. We conclude that our data justify the further exploration of our signature set as biomarkers to diagnose childhood TB. Furthermore, as the identification of different biomarkers in ethnically distinct cohorts is apparent, it is important to cross-validate newly identified markers in all available cohorts. In this study, 27 children 1 to 15 years of age with TB (n=9), LTBI (n=9) and HC (n=9) were recruited between May 2010 and December 2010. Tuberculin skin test (TST) and QuantiFERON-TB Gold In-Tube assay (QFT-GIT) were performed on all children. A sputum sample was collected from all children with expectoration and a gastric aspirate was taken from all children under 6 years of age. Children with active TB were diagnosed based on culture of M. tuberculosis (n=2) or on the basis of clinical, epidemiological and radiological features (n=7). The latter group were children with a TST = 10 mm or a positive QFT-GIT result who presented all of: persistent fever >38°C objectively recorded daily for at least two weeks, persistent cough for more than three weeks, weight loss (>5% reduction in weight compared with the highest weight recorded in last three months) or failure to thrive (documented crossing of percentile lines in the preceding three months), persistent lethargy or decrease in playfulness/activity reported by the parent and absence of clinical response on broad-spectrum antibiotics. Standard antero-posterior and lateral chest radiographs (CXRs) were taken from all children. Two independent experts, blinded to all clinical information, evaluated the CXRs and documented their findings on a standard report form. Where the two objective experts disagreed, a third expert was consulted and final consensus was achieved. A diagnosis of TB was only made when the CXR was consistent with TB9 and the child showed a positive clinical response to anti-TB treatment. Children were followed up clinically, radiologically and, in case of a negative TST at inclusion, by means of TST at six and 12 months after inclusion. LTBI was defined as a TST = 10mm and a positive QFT-GIT with a negative culture result on inclusion in the absence of radiological and clinical evidence of TB disease on inclusion as well as on t=6 and t=12 months. HC were children with a TST = 0 mm at inclusion and at t=6 and t=12 months. The HC had a negative QFT-GIT and a negative culture result at inclusion without radiological or clinical evidence of TB disease on inclusion nor on t=6 and t=12 months. TB patients were sampled before initiation of anti-TB treatment. Of three of the nine TB patients, a follow-up sample was taken when the patient was in anti-TB treatment for five months. All children were HIV-negative. 27 samples in total where analyzed, active TB infection (TB, n=9), Latent TB infection (LTBI, n=9) and healthy controls (HC, n=9) . Gene expression values were log2-transformed and differentially expressed genes were identified based on log2 fold changes (M-values). P values were calculated with a Bayes-regularized one-way ANOVA. Random Forest recursive feature elimination was used to find a signature geneset capable of discrimination active TB from latent TB and from non-infected individuals.
Project description:Heparan sulfate (HS), a long linear polysaccharide, is implicated in various steps of tumorigenesis, including angiogenesis. We successfully interfered with HS biosynthesis using a peracetylated 4-deoxy analog of the HS constituent GlcNAc and studied the compound’s metabolic fate and its effect on angiogenesis. The 4-deoxy analog was activated intracellularly into UDP-4-deoxy-GlcNAc and HS expression was inhibited up to ~96% (IC50 = 16 µM). HS chain size was reduced, without detectable incorporation of the 4-deoxy analog, likely due to reduced levels of UDP-GlcNAc and/or inhibition of glycosyltransferase activity. Comprehensive gene expression analysis revealed reduced expression of genes regulated by HS binding growth factors as FGF-2 and VEGF. Cellular binding and signaling of these angiogenic factors was inhibited. Micro-injection in zebrafish embryos strongly reduced HS biosynthesis, and angiogenesis was inhibited in both zebrafish and chicken model systems. All these data identify 4-deoxy-GlcNAc as a potent inhibitor of HS synthesis which hampers pro-angiogenic signaling and neo-vessel formation. 9 samples were analyzed: 3 biological replicates from untreated SKOV3 cells, 3 biological replicates from SKOV3 cells treated with peracetylated GlcNAc, 3 biological replicates from SKOV3 cells treated with peracetylated 4-deoxy-GlcNAc