Cells undergoing apoptosis are known to modulate their tissue microenvironments. By acting on phagocytes, notably macrophages, apoptotic cells inhibit immunological and inflammatory responses and promote trophic signaling pathways. Paradoxically because of their potential to cause death of tumor cells and thereby militate against malignant disease progression, both apoptosis and tumor-associated macrophages (TAM) are often associated with poor prognosis in cancer. In order to better understand the influence of tumor cell apoptosis and in particular its effect on TAM, we investigated global gene expression signatures of undisturbed TAM engaged in engulfment of apoptotic tumor cells. We studied a xenograft model of an aggressive starry-sky non-Hodgkins lymphoma, Burkitts lymphoma (BL), in which apoptotic tumor cells are common and frequently observed in association with the starry-sky TAM (SS-TAM, so called because they appear histologically as stars in a sky of tumor cells) that accumulate in these tumors. We used a BL cell line (BL2) whose cells phenotypically resemble the tumor biopsy cells from which the line was derived including the capacity to undergo apoptosis constitutively. BL xenografts in SCID mice closely recapitulated the starry-sky histological picture of the human lymphoma. Due to the high sensitivity of macrophages to their environments, we adopted laser-capture microdissection of individual SS-TAM in BL xenografts in order to obtain unbiased in situ transcriptional profiles of these cells, which we compared specifically with those of similarly-captured macrophages, the tingible-body macrophages from normal germinal centers (GCM). The rationale for this comparison was based upon BL being a germinal center malignancy and tingible-body macrophages being regarded as normal equivalents of SS-TAM.
Oncogenic properties of apoptotic tumor cells in aggressive B cell lymphoma.
Sex, Specimen part
View SamplesMetastasis to lymph nodes is an early and prognostically important event in the progression of many human cancers, and is associated with expression of vascular endothelial growth factor-D (VEGF-D). Changes to lymph node vasculature occur during metastasis, and may establish a metastatic niche capable of attracting and supporting tumor cells.
A role for bone morphogenetic protein-4 in lymph node vascular remodeling and primary tumor growth.
Sex, Specimen part
View SamplesMuscle denervation due to injury, disease or aging results in impaired motor function. Restoring neuromuscular communication requires axonal regrowth and regeneration of neuromuscular synapses. Muscle activity inhibits neuromuscular synapse regeneration. The mechanism by which muscle activity regulates regeneration of synapses is poorly understood. Dach2 and Hdac9 are activity-regulated transcriptional co-repressors that are highly expressed in innervated muscle and suppressed following muscle denervation. Here, we report that Dach2 and Hdac9 inhibit regeneration of neuromuscular synapses. Importantly, we identified Myog and Gdf5 as muscle-specific Dach2/Hdac9-regulated genes that stimulate neuromuscular regeneration in denervated muscle. Interestingly, Gdf5 also stimulates presynaptic differentiation and inhibits branching of regenerating neurons. Finally, we found that Dach2 and Hdac9 suppress miR206 expression, a microRNA involved in enhancing neuromuscular regeneration. Overall design: RNAseq on innervated and 3 day denervated adult soleus muscle from wildtype mice is compared with that from 3 day denervated soleus muscle from Dach2/Hdac9 deleted mice to identify Dach2/Hdac9-regulated genes.
Dach2-Hdac9 signaling regulates reinnervation of muscle endplates.
No sample metadata fields
View SamplesDuplicated genes escape gene loss by conferring a dosage benefit or evolving diverged functions. The yeast Saccharomyces cerevisiae contains many duplicated genes encoding ribosomal proteins. Prior studies have suggested that these duplicated proteins are functionally redundant and affect cellular processes in proportion to their expression. In contrast, through studies of ASH1 mRNA in yeast, we demonstrate paralog-specific requirements for the translation of localized mRNAs. Intriguingly, these paralog-specific effects are limited to a distinct subset of duplicated ribosomal proteins. Moreover, transcriptional and phenotypic profiling of cells lacking specific ribosomal proteins reveals differences between the functional roles of ribosomal protein paralogs that extend beyond effects on mRNA localization. Finally, we show that ribosomal protein paralogs exhibit differential requirements for assembly and localization. Together, our data indicate complex specialization of ribosomal proteins for specific cellular processes, and support the existence of a ribosomal code.
Functional specificity among ribosomal proteins regulates gene expression.
No sample metadata fields
View SamplesTo understand the funtion of Colorectal cancer GWAS results, we perform a comprehensive analysis using biofeatures of HCT116 colon cancer cell line and got a list of risk-asscociated SNP. Risk-associated SNP are likely exerting their effects through promoters or enhancer. In order to understand the importance of the genes with risk-associated SNP in their promoters and enhancers'' putatively targeted genes, we did a comparison of these genes between HCT116 colon cancer cell and normal colon and try to understand their function Overall design: Two biological replicates of HCT116 were compared to the data of two normal colon samples already deposited in GEO (GSM1010974 and GSM1010942).
Functional annotation of colon cancer risk SNPs.
No sample metadata fields
View SamplesWhile transcriptional regulation of stem cell self-renewal and differentiation has been extensively studied, only a small number of studies have addressed the roles for post-translational modifications in these processes. A key mechanism of post-translational modification is ubiquitination by the ubiquitin-proteasome system (UPS). Using UPS-targeted RNAi screens, we identify novel regulators of pluripotency and differentiation. We focus on two of these proteins, the deubiquitinating enzyme, Psmd14, and the E3 ligase, Fbxw7, and characterize their importance in ES cell pluripotency and cellular reprogramming.
Regulation of pluripotency and cellular reprogramming by the ubiquitin-proteasome system.
Specimen part, Cell line
View SamplesWhile transcriptional regulation of stem cell self-renewal and differentiation has been extensively studied, only a small number of studies have addressed the roles for post-translational modifications in these processes. A key mechanism of post-translational modification is ubiquitination by the ubiquitin-proteasome system (UPS). Using UPS-targeted RNAi screens, we identify novel regulators of pluripotency and differentiation. We focus on two of these proteins, the deubiquitinating enzyme, Psmd14, and the E3 ligase, Fbxw7, and characterize their importance in ES cell pluripotency and cellular reprogramming.
Regulation of pluripotency and cellular reprogramming by the ubiquitin-proteasome system.
Specimen part, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Regulation of pluripotency and cellular reprogramming by the ubiquitin-proteasome system.
Specimen part, Cell line
View SamplesWe have analyzed publicly available K562 Hi-C data, which enables genome-wide unbiased capturing of chromatin interactions, using a Mixture Poisson Regression Model to define a highly specific set of interacting genomic regions. We integrated multiple ENCODE Consortium resources with the Hi-C data, using DNase-seq data and ChIP-seq data for 46 transcription factors and 8 histone modifications. We classified 12 different sets (clusters) of interacting loci that can be distinguished by their chromatin modifications and which can be categorized into three types of chromatin hubs. The different clusters of loci display very different relationships with transcription factor binding sites. As expected, many of the transcription factors show binding patterns specific to clusters composed of interacting loci that encompass promoters or enhancers. However, cluster 6, which is distinguished by marks of open chromatin but not by marks of active enhancers or promoters, was not bound by most transcription factors but was highly enriched for 3 transcription factors (GATA1, GATA2, and c-Jun) and 3 chromatin modifiers (BRG1, INI1, and SIRT6). To validate the identification of the clusters and to dissect the impact of chromatin organization on gene regulation, we performed RNA-seq analyses before and after knockdown of GATA1 or GATA2. We found that knockdown of the GATA factors greatly alters the expression of genes within cluster 6. Our work, in combination with previous studies linking regulation by GATA factors with c-Jun and BRG1, provide genome-wide evidence that Hi-C data identifies sets of biologically relevant interacting loci. Overall design: RNA-seq of control, siGATA1 and siGATA2 K562 cells
Integration of Hi-C and ChIP-seq data reveals distinct types of chromatin linkages.
Cell line, Subject
View SamplesBackground: The ZNF217 gene, encoding a C2H2 zinc finger protein, is located at 20q13 and found amplified and overexpressed in greater than 20% of breast tumors. Current studies indicate ZNF217 drives tumorigenesis, yet the regulatory mechanisms of ZNF217 are largely unknown. Because ZNF217 associates with chromatin modifying enzymes, we postulate that ZNF217 functions to regulate specific gene signaling networks. Here, we present a large-scale functional genomic analysis of ZNF217, which provides insights into the regulatory role of ZNF217 in MCF7 breast cancer cells. Results: ChIP-seq analysis reveals that the majority of ZNF217 binding sites are located at distal regulatory regions associated with the chromatin marks H3K27ac and H3K4me1. Analysis of ChIPseq transcription factor binding sites shows clustering of ZNF217 with FOXA1, GATA3 and ERalpha binding sites, supported by the enrichment of corresponding motifs for the ERalpha-associated cisregulatory sequences. ERalpha expression highly correlates with ZNF217 in lysates from breast tumors (n=15), and ERalpha co-precipitates ZNF217 and its binding partner CtBP2 from nuclear extracts. Transcriptome profiling following ZNF217 depletion identifies differentially expressed genes co-bound by ZNF217 and ERalpha; gene ontology suggests a role for ZNF217-ERalpha in expression programs associated with ER+ breast cancer studies found in the Molecular Signature Database. Data-mining of expression data from breast cancer patients correlates ZNF217 with reduced overall survival in multiple subtypes. Conclusions: Our genome-wide ZNF217 data suggests a functional role for ZNF217 at ERalpha target genes. Future studies will investigate whether ZNF217 expression contributes to aberrant ERalpha regulatory events in ER+ breast cancer and hormone resistance Overall design: Differential RNA-seq profiling from triplicate biological replicates of MCF7 cells treated with scrambled siRNA or siZNF217.
Global analysis of ZNF217 chromatin occupancy in the breast cancer cell genome reveals an association with ERalpha.
No sample metadata fields
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