This SuperSeries is composed of the SubSeries listed below.
Genome-wide mapping of DNA hydroxymethylation in osteoarthritic chondrocytes.
Specimen part
View SamplesExamination of the genome-wide distribution of 5hmC in osteoarthritic chondrocytes compared to normal chondrocytes in order to elucidate the effect on OA-specific gene expression.
Genome-wide mapping of DNA hydroxymethylation in osteoarthritic chondrocytes.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Stable 5-Hydroxymethylcytosine (5hmC) Acquisition Marks Gene Activation During Chondrogenic Differentiation.
Specimen part
View SamplesRegulation of chondrogenic differentiation by DNA demethylation is little understood. The ten-eleven-translocation (TET) proteins oxidize methylated cytosines (5mC) to 5hmC, 5fC and 5caC eventually leading to DNA demethylation. However, 5hmC is stable and can potentially act as an epigenetic mark as well. In this study, we report that global changes in 5hmC mark chondrogenic differentiation.
Stable 5-Hydroxymethylcytosine (5hmC) Acquisition Marks Gene Activation During Chondrogenic Differentiation.
Specimen part
View SamplesDespite continual efforts to rationalize a prognostic stratification of patients with esophageal adenocarcinoma (EAC) before treatment, current staging system only shows limited success owing to the lack of molecular and genetic markers that reflect prognostic features of the tumor. To develop molecular predictors of prognosis, we used systems-level characterization of tumor transcriptome. Using DNA microarray, genome-wide gene expression profiling was performed on 75 biopsy samples from patients with untreated EAC. Various statistical and informatical methods were applied to gene expression data to identify potential biomarkers associated with prognosis. Potential marker genes were validated in an independent cohort using quantitiative RT-PCR to measure gene expression. Distinct subgroups of EAC were uncovered by systems-level characterization of tumor transcriptome. We also identified a six-gene expression signature that could be used to predict overall survival (OS) of EAC patients. In particular, expression of SPARC and SPP1 was a strong independent predictor of OS, and a combined gene expression signature with these two genes was associated with prognosis (P < 0.024), even when all relevant pathological variables were considered together in multivariate Cox hazard regression analysis. Our findings suggest that molecular features reflected in gene expression signatures may dictate the prognosis of EAC patients, and these gene expression signatures can be used to predict the likelihood of prognosis at the time of diagnosis and before treatment.
Prognostic biomarkers for esophageal adenocarcinoma identified by analysis of tumor transcriptome.
No sample metadata fields
View SamplesRemoval of introns by pre-mRNA splicing is a critical and in some cases rate-limiting step in mammalian gene expression. Deep sequencing of mouse embryonic stem cell RNA revealed many specific internal introns that are significantly more abundant than the other introns within poly(A) selected transcripts; we classify these as “detained” introns (DIs). We identified thousands of DIs flanking both constitutive and alternatively spliced exons in human and mouse cell lines. Drug inhibition of Clk SR-protein kinase activity triggered rapid splicing changes in a specific set of DIs, about half of which showed increased splicing and half increased intron detention, altering the transcript pool of over 300 genes. These data suggest a widespread mechanism by which a nuclear detained pool of mostly processed pre-mRNAs can be rapidly mobilized in response to stress or homeostatic autoregulation. Overall design: v6.5 mouse embryonic stem cells were untreated, treated with the Clk kinase inhibitor KH-CB19, or treated with DMSO as a negative control. Untreated cells were harvested and a single replicate was sequenced using a custom, ligation-based, stranded library preparation protocol. Treated cells were harvested at time 0 and at 2 hours post-treatment, and poly(A)-selected RNA-seq libraries were made from biological duplicates for each treatment/time, barcoded, and sequenced by strand-specific, paired-end sequencing using the Illumina TruSeq kit.
Detained introns are a novel, widespread class of post-transcriptionally spliced introns.
No sample metadata fields
View SamplesThe epigenetic regulator BMI1 is upregulated in many human malignancies and has been implicated in cell migration, but the impact on autochthonous tumor progression is unexplored. Our analyses of human expression data show that BMI1 levels increase with progression in melanoma. We find that BMI1 expression in melanoma cells does not influence cell proliferation or primary tumor growth. In contrast, BMI1 levels are a key determinant of melanoma metastasis, whereby deletion impairs and overexpression enhances dissemination. Remarkably, BMI1’s pro-metastatic effect reflects enhancement of all stages of the metastatic cascade including invasion, migration, extravasation, adhesion and survival. Additionally, downregulation or upregulation of BMI1 induces sensitivity or resistance to BRAF inhibitor. Consistent with these pleiotropic effects, we find that BMI1 promotes widespread gene expression changes that encompass key hallmarks of the melanoma invasive signature, including activation of TGFß, non-canonical Wnt, EMT and EGF/PDGF pathways. Importantly, for both primary and metastatic melanoma samples, this BMI1-induced signature identifies invasive subclasses of human melanoma and predicts poor patient outcome. Our data yield key insights into melanoma biology and establish BMI1 as a compelling drug target whose inhibition would suppress both metastasis and chemoresistance. Overall design: Three replicates of A375 BMI1 or GFP overexpressing cells.
BMI1 induces an invasive signature in melanoma that promotes metastasis and chemoresistance.
No sample metadata fields
View SamplesTumor cells have an increased need for amino acids. Mammalian cells cannot synthesize essential amino acids; they must obtain these amino acids via specific transporters. Glutamine, though a non-essential amino acid, is critical for tumor cells (glutamine addiction). Entry of amino acids into tumor cells is enhanced by upregulation of specific transporters. If the transporters that are specifically induced in tumor cells are identified, blockade of the induced transporters would constitute a logical strategy for cancer treatment.
Deletion of the amino acid transporter Slc6a14 suppresses tumour growth in spontaneous mouse models of breast cancer.
Age, Specimen part
View SamplesMicroRNAs (miRNAs) are a large family of 19-22nt non-coding RNAs that post-transcriptionally regulate their mRNA targets. Computational algorithms predict that over half of all genes are regulated by miRNAs, yet approaches for experimental identification of miRNA binding sites are now emerging. To directly identify endogenous miRNA binding sites, we performed photo-crosslinking immunoprecipitation using antibodies against Ago2, followed by deep-sequencing of RNA tags (CLIP-seq) in mouse embryonic stem cells (mESCs). We also performed parallel CLIP-seq in Dicer null mESCs that lack mature miRNAs, allowing us to define whether the association of Ago2 with the identified sites was mediated by miRNAs. We include the exon-array expression data obtained from three sets of Dicer WT and Dicer Null mESCs.These data are used to determine genes that are differentially expressed between Dicer WT and Dicer Null conditions. Overall design: Six samples (3 Dicer wild-type CLIP RNA libraries representing two biological replicates, 2 Dicer null CLIP RNA libraries, 1 short-RNA library from Dicer wild-type mESCs) were analyzed. Six total mESC samples were analyzed (3 Dicer WT, 3 Dicer Null). Expression values for probesets were summarized into a single per-gene value. The log fold change for Dicer_WT/Dicer_Null was defined as the difference between the mean expression in Dicer WT mESCs and the mean expression in the Dicer Null mESCs.
Genome-wide identification of Ago2 binding sites from mouse embryonic stem cells with and without mature microRNAs.
No sample metadata fields
View SamplesDicer knockout NSCLC mRNAseq profiles the transcriptome, Dicer knockout NSCLC miRseq profiles the miRnome Overall design: DicerHet and DicerKO NSCLC, 2 biological reps each genotype for mRNAseq, 1 biological rep each for miRseq
Global microRNA depletion suppresses tumor angiogenesis.
No sample metadata fields
View Samples