Large-scale epigenetic reprogramming is punctuated late during the evolution of pancreatic cancer progression
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Xin Li
PROVIDER: E-GEOD-63126 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:During pancreatic cancer progression, heterogeneous subclonal populations evolve in the primary tumor that possess differing capacities to metastasize and cause patient death. However, the genetics of metastasis reflects that of the primary tumor, and PDAC driver mutations arise early. This raises the possibility than an epigenetic process could be operative late. Using an exceptional resource of paired patient samples, we found that different metastatic subclones from the same patient possessed remarkably divergent malignant properties and global epigenetic programs. Global reprogramming was targeted to thousands of large chromatin domains across the genome that collectively specified malignant divergence. This was maintained by a metabolic shift within the pentose phosphate pathway, independent of KRAS driver mutations. Analysis of paired primary and metastatic tumors from multiple patients uncovered substantial epigenetic heterogeneity in primary tumors, which resolved into a terminally reprogrammed state in metastatic lesions. This supports a model whereby driver mutations accumulate early to initiate pancreatic tumorigenesis, followed by a period of subclonal evolution that generates sufficient intra-tumor heterogeneity for selection of epigenetic programs that may increase fitness during malignant progression and metastatic spread. To map the epigenomic landscape of pancreatic cancer progression as it evolves within patients. Chip-Seq (K27Me3, K36Me3, K9Me2/3, K4Me3 and K27Ac) of 2 patients (A13 and A38) and HPDE cell line. Patient A38 included local peritoneal metastasis and 2 distant metastsis (liver and lung mets), and 6AN treated and DMSO samples for lung matastasis. Patient A13 included 2 primary tumors and 1 distant lung metastasis. Each sample has been done with replicates.
2016-10-24 | E-GEOD-63125 | biostudies-arrayexpress
Project description:Purpose: To determine H3K4me3 chromatin profile in UBC9WT and UBC9KO BMDC before and after LPS stimulation. Methods: H3K4me3 chromatin profile was determined by sequencing UBC9 WT and UBC9 KO BMDC chromatin immunoprecipitated with antibody specific for H3K4me3. Results: We show differential chromatin profile for H3K4me3 on the ifnb1 locus between UBC9 KO cells and UBC9 WT. Conclusions: Loss of SUMOylation causes a deregulation of ifnb1 transcription activation mark. A study of H3K4me3 chromatin profile in UBC9 WT and UBC9 KO Bone Marrow derived Dendritic Cells.
2015-12-14 | E-GEOD-66338 | biostudies-arrayexpress
Project description:To get insight into TRIM33 functions, TRIM33 ChIP-seq was carried out in murine macrophage cell line (RAW) and in bone marrow-derived macrophages (BMDM). The results showed that, in addition to its role in hematopoietic differentiation, TRIM33 may modulate PU.1 transcriptional activity during macrophage development and/or activation.To characterize the role of TRIM33 in macrophages, we bred TRIM33fl/fl mice with Lyz-Cre mice where the Cre recombinase gene is under the regulatory sequences of the Lyz gene that is expressed only in mature myeloid cells. Bone marrow cells from LyzCre/Trim33+/+ mice and LyzCre/Trim33flox/flox mice were differentiated in macrophages and treated during 0h, 4h, 12h and 24h with LPS. Using ChIP-seq, we provide a link between TRIM33 binding and H3K4me3 spreading on inflammatory genes in macrophages. Chromatin immunoprecipitations of TRIM33 and H3K4Me3 followed by multiparallel sequencing performed in murine bone marrow-derived macrophages (BMDM).
2015-11-23 | E-GEOD-43654 | biostudies-arrayexpress
Project description:The active vitamin A derivative retinoic acid (RA) is an important regulator of adult brain functions. How these regulations are achieved is poorly known, partly due to the paucity of information on RA molecular targets. The striatum, the region involved in control of motor, cognitive and affective functions, may be particularly prone to such regulation as it displays the highest levels of RA and its receptors (RARs). We report the first genome-wide analysis of RAR-binding sites in the brain. Using chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq), as well as transcriptomic analysis of RARβ-null mutant mice, we identified genomic transcriptional targets of RARβ in the striatum. Our data point to a strong contribution of RARβ in controlling neurotransmission, energy metabolism, and transcription, with a particular involvement of G-protein, cAMP and calcium signaling. Quantitative PCR analysis of striatal subregions revealed a higher sensitivity of ventral structures (nucleus accumbens) to lack of RARβ signaling. There is a high overlap of transcriptional targets of RARβ and genes affected in expression in Huntingtonâs disease (HD), and we observed a decrease of RARβ expression in the striatum of R6/2 transgenic mice, a murine model of HD. A large number of genes bearing RARβ binding sites have also been implicated in Alzheimerâs and Parkinsonâs diseases, raising the possibility that compromised RA signaling in striatum may be a mechanistic link explaining the similar affective and cognitive symptoms of these diseases. Globally, our data point to a possibility of a neuroprotective function of RARβ in the striatum. Genome-wide mapping of RARβ and H3K4me3 binding sites in mouse caudate putamen
2016-07-22 | E-GEOD-67829 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2015-12-14 | E-GEOD-66339 | biostudies-arrayexpress
Project description:The nuclear receptor HNF4A regulates embryonic and post-natal hepatocyte gene expression. Using hepatocyte-specific inactivation in mice, we show that the TAF4 subunit of TFIID acts as a cofactor for HNF4A in vivo and that HNF4A interacts directly with the TAF4-TAF12 heterodimer in vitro. In vivo, TAF4 is required to maintain HNF4A-directed embryonic gene expression at post-natal stages and for HNF4A-directed activation of post-natal gene expression. TAF4 promotes HNF4A occupancy of functional cis-regulatory elements located adjacent to the transcription start sites of post-natal expressed genes and for pre-initiation complex formation required for their expression. Promoter-proximal HNF4A-TFIID interactions are therefore required for pre-initiation complex formation and stable HNF4A occupancy of regulatory elements as two concomitant mutually dependent processes. Examination of PIC, H3k4me3, Ctcf and Hnf4a occupancy in wild-type and Taf4-/- livers by deep sequencing
2014-09-25 | E-GEOD-57807 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2014-09-25 | E-GEOD-57814 | biostudies-arrayexpress
Project description:We used an immature mouse T cell line engineered to express a biotinylated form of the cleaved form of Notch1 (ICN1). ICN1-bound sites were precipitated with streptavidin-coated beads and subjected to ChIP-sequencing. Beko cells correspond to a spontaneous T lymphoma immature cell line derived from a TCRb deficient mouse. These cells were engineered to express a biotin-tagged-ICN1 and the bacterial biotin ligase BirA (Bio-ICN1) or just BirA as a control (Bio). Chromatin from both cell lines was subjected to strepatavidin-mediated precipitation and subjected to sequencing with the Illumina GAII sequencer as single end 36 base pair reads.
2014-04-02 | E-GEOD-46114 | biostudies-arrayexpress
Project description:The transcription factor Ikaros represses Notch signaling. Since Ikaros and Notch treanscriptional mediator RBPJ both recognize sequences that contain the same core TGGGAA motif, it was hypothesized that Ikaros represses Notch signaling by targeting Notch response elements and competing with RBPJ for their binding. Here we used the mouse T-cell leukemia cell line T29 to compare the genomic binding profiles of Ikaros and RBPJ by ChIP-seq. The T29 cell line is derived from a Ikaros-deficient T-cell leukemia (Dumortier et al, MCB 26, 209-220, 2006) and exhibits strong Notch activation. We performed two chip-seq experiments with an anti-RBPJ antibody to map RBPJ binding sites. To map Ikaros binding sites, we engineered a T29-derived cell line that expresses a fusion protein between Ikaros and the ligand binding domain of the estrogen receptor (Ik1-ER) which is activated by addition of 4-hydroxy-tamoxifen (4OHT). We used an anti-Ikaros antibody to map the sites bound by Ik1-ER after treatment of the cells with 4OHT. Sequencing were performed with the Illumina GAII sequencer as as single end 36 base pair reads.
2014-04-02 | E-GEOD-46119 | biostudies-arrayexpress
Project description:Microphthalmia-associated transcription factor (MITF) is the master regulator of the melanocyte lineage. By tandem affinity purification and mass spectrometry, we present a comprehensive characterisation of the MITF interactome comprising multiple novel cofactors involved in transcription, DNA replication and repair and chromatin organisation, including a BRG1 chromatin remodelling complex comprising CHD7. BRG1 is essential for melanoma cell proliferation in vitro and for normal melanocyte development in vivo. MITF and SOX10 actively recruit BRG1 to a set of MITF-associated regulatory elements (MAREs) at active enhancers. MITF, SOX10 and YY1 bind between two BRG1-occupied nucleosomes thus defining both a combinatorial signature of transcription factors essential for the melanocyte lineage and a specific chromatin organisation of MAREs. Nevertheless, BRG1 silencing enhances MITF occupancy at MAREs showing that BRG1 acts to promote dynamic MITF interactions with chromatin. 19 samples corresponding to mRNA profiles of 501Mel and Hermes3A after MITF, BRG1 or control shRNA-mediated knockdown were generated by deep sequencing in triplicate (in duplicate for 501_shMITF and corresponding control 501_shSCR2), using HiSeq2500.
2015-04-02 | E-GEOD-61966 | biostudies-arrayexpress