Expression analysis of prostate tissue on locus 8q24 part 3
ABSTRACT: Investigation on expression levels of normal tissue from prostate cancer patients on locus 8q24. 3 chips with 3 arrays each study, using 3 pairs of normal vs. tumor tissue and 3 replicates of the same sample. Each chip contained one pair of normal vs. tumor and one copy of the repeated sample.
Project description:Investigation on expression levels of normal tissue from prostate cancer patients on locus 8q24. The region chr8:127640000-129120000 is tiled with isothermal probes (hg17) 7 chip study, using 7 independent samples.
Project description:Investigation on expression levels of normal tissue from prostate cancer patients on locus 8q24. The region chr8:127640000-129120000 is tiled with 60 nt probes at 10 nt interval (hg18) 7 chip study, using 7 independent samples.
Project description:Embryonic stem cells (ESCs) and induced-pluripotent stem cells (iPSCs) self-renew and differentiate into an array of cell types in vitro and in vivo. A complex network of genetic and epigenetic pathways regulates the self-renewal and differentiation of these pluripotent cells, and the structure and covalent modifications of chromatin play a prominent role in this process. We examine nucleosome occupancy in mouse and human embryonic stem cells (ESCs), induced-pluripotent stem cells (iPSCs), and differentiated cell types using MNase-seq. To address variability inherent in this technique, we developed a bioinformatic approach that enabled the identification of regions of difference (RoD) in nucleosome occupancy between pluripotent and somatic cells. The majority of changes in nucleosomal signatures that occur in differentiation are reset during reprogramming. We conclude that changes in nucleosome occupancy are a hallmark of pluripotency and likely identify key regulatory regions that play a role in determining cell identity. A six chip study using total RNA recovered from three cell types with 2 replicates each
Project description:Investigation of whole genome gene expression level changes of LncRNAs in tumor tissues and paired non-tumor tissues in HBV-positive hapatocellular carcinoma. The different expression genes were further analysised. The human LncRNA microarray analysis of the 10 samples (5 non-tumor tissues and 5 paired tumor tissues) were completed. Total RNA from each sample was quantified using the NanoDrop ND-1000 and RNA integrity was assessed using standard denaturing agarose gel electrophoresis. Total RNA of each sample was used for labeling and array hybridization as the following steps: 1) Reverse transcription with by Invitrogen Superscript ds-cDNA synthesis kit; 2) ds-cDNA labeling with NimbleGen one-color DNA labeling kit; 3) Array hybridization using the NimbleGen Hybridization System and followed by washing with the NimbleGen wash buffer kit; 4) Array scanning using the Agilent Scanner G2505C. Scanned images (TIFF format) were then imported into NimbleScan software (version 2.5) for grid alignment and expression data analysis. Expression data were normalized through quantile normalization and the Robust Multichip Average (RMA) algorithm included in the NimbleScan software. The Probe level (*_norm_RMA.pair) files and mRNA level (*_RMA.calls) files were generated after normalization. All mRNAs level files were imported into Agilent GeneSpring GX software (version 11.5.1) for further analysis.mRNAs that at least 3 out of 6 samples have values greater than or equal to lower cut-off: 50.0 (“All Targets Value”) were chosen for further data analysis. Differentially expressed mRNAs were identified through Volcano Plot filtering. Pathway analysis and GO analysis were applied to determine the roles of these differentially expressed mRNAs played in these biological pathways or GO terms. Finally, Hierarchical Clustering was performed to show the distinguishable mRNAs expression pattern among samples.
Project description:Hepatoarcinogenesis is a slow and multistep process. We used Hepatitis B virus X antigen (HBx) induced Hepatocellular carcinoma (HCC) as model. We also identify the biomarkers, the pathways and networks underlying HCC formation in this animal model. We analyzed the events from the early, middle, and late stages, in order to predict and prevent the development of cancer. At each specific stage, we analyzed the expression level that differed at least two-fold between HBx transgenic and wild-type mouse liver. Statistical approaches were used to identify genes displaying an increasing or decreasing trend throughout hepatocarcinogenesis. The liver was excised from 6-week-, 8-month-, 12-month-, 14-month-, and 16-month-old HBx transgenic mice (A106 strain) and RNA samples were isolated. In both 14-month- and 16-month-old mice, samples were obtained from both the tumor tissue and the normal.
Project description:A significant percentage of HIV-infected individuals experience a sharp decline in CD4+ T cell counts and progress to AIDS quickly after primary infection. Identification of biomarkers distinguishing rapid progressors (RPs) versus chronic progressors (CPs) is critical for early clinical intervention and could provide novel strategies to facilitate vaccine design and immune therapy. mRNA and miRNA expression profiles in the peripheral blood mononuclear cells (PBMCs) of RPs and CPs were investigated at 111±22 days (Mean±SD) of HIV infection. The association of mRNA and miRNA expression with disease progression was examined by receiver operating characteristic analysis and Kaplan-Meier survival analysis. Pathway enrichment analysis showed that genes with deregulated expression in RPs are primarily involved in apoptosis pathways. Furthermore, we found that 5 miRNAs (miR-31, -200c, -526a, -99a and -503) in RPs were significantly decreased compared to those in CPs (P<0.05). The decreased expression of these miRNAs was associated with rapid disease progression of HIV infection with a 94% predictive value as measured by the area under the curve. The upregulated predicted targets from the 5 signature miRNAs and all upregulated genes identified from mRNA microarray converged to the apoptosis pathway. Moreover, overexpression of miR-31 in primary human T cells promoted their survival. Our results have identified a distinct transcriptomic signature in PBMCs of RPs and provided novel insights to the pathogenesis of HIV infection. A cohort of primary HIV infected individuals with different disease outcome were enrolled in this study. We included 6 individuals with rapid disease progression (RP), seven with chronic disease progression (CP). The HIV infected individuals were never on therapy before the time of sample taken.
Project description:The human gut microbe Bacteroides fragilis can alter the expression of its surface molecules such as capsular polysaccharides and SusC/SusD family outer membrane proteins through the reversible DNA inversions. We have revealed that the outer membrane vesicle (OMV) formation in B. fragilis is regulated by BF2766 (tyrosine recombinase)-mediated DNA inversions at two distantly located promoter regions previously designated as class IV regions. In this study, we aimed to identify the genetic loci associating with the OMV formation by means of transcriptome analysis on the isogenic BF2766 mutants. By comparing the transciptomes of four BF2766 deletion mutants, in which the promoter orientations in class IV-1 and IV-2 regions were locked ON/ON, OFF/ON, OFF/OFF, or ON/OFF, we found that the transcription of the genes downstream of class IV-2 markedly elevated in a hyper-vesiculating ON/ON strain. A four chip study using total RNA isolated from four BF2766 deletion mutants culture. Each sample contains duplicated data.
Project description:Variation in chromatin composition and organization often reflects differences in genome function. Histone variants, for example, replace canonical histones to contribute to regulation of numerous nuclear processes including transcription, DNA repair and chromosome segregation. Here we focus on H2A.Bbd, a rapidly evolving variant found in mammals but not in invertebrates. We report that in human cells, nucleosomes bearing H2A.Bbd form unconventional chromatin structures enriched within actively transcribed genes and characterized by shorter DNA protection and nucleosome spacing. Analysis of transcriptional profiles from cells depleted for H2A.Bbd demonstrated widespread changes in gene expression with a net down-regulation of transcription and disruption of normal mRNA splicing patterns. In particular, we observed changes in exon inclusion rates and increased presence of intronic sequences in mRNA products upon H2A.Bbd depletion. Taken together, our results indicate that H2A.Bbd is involved in formation of a specific chromatin structure that facilitates both transcription and initial mRNA processing. Gene expression was measured in two replicates of the HeLa cells expressing H2A.Bbd-FLAG histone, which were treated with shRNA with no homology to the human genome.
Project description:Investigation of gene expression level changes in Petunia hybrida seedlings subjected to cold at 2°C for 0.5 h, 2 h, 24 h and 5 d, compared to the CK. The custom-designed four-plex microarray with 72000 features was constructed based on the EST sequences generated in Breuillin's study together with all sequences of P.hybrida and P.axillaris available at Genbank, TIGR, and the Solanaceae genomics network SGN, which was ultimately composed by a set of 24816 non-redundant unique sequences (unigenes).The probe intensity files resulting from RNA hybridization were first read into R. Background Correction, quantile normalization and summarization were then performed using the Robust Multi-array Average (RMA) method included in Bioconductor Affy package based on the home made chip description library.