This SuperSeries is composed of the SubSeries listed below.
Compensatory RNA polymerase 2 loading determines the efficacy and transcriptional selectivity of JQ1 in Myc-driven tumors.
Specimen part, Treatment
View SamplesWe here use B-cell tumors as a model to address the mechanism of action of JQ1, a widely used BET inhibitor.
Compensatory RNA polymerase 2 loading determines the efficacy and transcriptional selectivity of JQ1 in Myc-driven tumors.
Treatment
View SamplesThe tumor suppressor p53 is a transcription factor that controls the response to stress. Here, we dissected the transcriptional programs triggered upon restoration of p53 in Myc-driven lymphomas, based on the integrated analysis of p53 genomic occupancy and gene regulation. p53 binding sites were identified at promoters and enhancers, both characterized by the pre-existence of active chromatin marks. p53 recruitment at these sites was mainly mediated through protein-protein or protein-chromatin interactions and, only for a small fraction, through recognition of the 20 base-pair p53 consensus motif. At promoters, p53 binding to the consensus motif was associated with gene induction, but not repression, indicating that the latter was most likely indirect. p53 also targeted unmarked distal sites devoid of activation marks, at which binding was prevalently driven by recognition of the consensus motif. At all sites, our data highlighted a functional role for the canonical, unsplit consensus element, but did not provide evidence for p53 recruitment by split motifs. Altogether, our data highlight key features of genome recognition by p53 and provide unprecedented insight into the pathways associated with p53 re-activation and tumor regression. Overall design: Total RNA profiling of gene expression in Eµ-myc lymphomas following p53 restoration by Illumina sequencing
Genome-wide analysis of p53-regulated transcription in Myc-driven lymphomas.
Specimen part, Cell line, Subject
View SamplesThe M1 and the M2 macrophage polarization programs (activated by IFN? and IL-4, respectively) lie at the opposite edges of a continuum of activation states but are frequently co-activated during co-infections and in cancer despite controlling divergent functional responses. Whether these two programs are mutually exclusive, how they influence each other, and whether one represents the prevailing response, are all open questions. Co-administration of IFN? and IL-4 exerted complex inhibitory effects over the M1 and M2 programs at the level of both epigenomic and transcriptional changes. Computational data mining and validation analyses revealed the molecular basis of the differential sensitivity of genes and cis-regulatory elements to the antagonistic effects of the opposite stimulus. For instance, while STAT1 and IRF motifs were associated with robust and IL-4-resistant responses to IFN?, their coexistence with binding sites for some auxiliary transcription factors such as AP-1, generated vulnerability to IL-4-mediated inhibition. These data provide a core mechanistic framework for the integration of signals that control macrophage activation and the starting point for understanding macrophage responses in complex environmental conditions Overall design: Analysis of transcriptional and epigenomic changes in mouse macrophages stimulated with different cytokines or their combinations
Opposing macrophage polarization programs show extensive epigenomic and transcriptional cross-talk.
Specimen part, Cell line, Treatment, Subject
View SamplesOver-expression of the Myc transcription factor causes its widespread interaction with regulatory domains in the genome, but leads to the up- and down-regulation of discrete sets of genes. The molecular determinants of these selective transcriptional responses remain elusive. Here, we present an integrated time-course analysis of transcription and mRNA dynamics following Myc activation in proliferating mouse fibroblasts, based on chromatin immunoprecipitation, metabolic labeling of newly synthesized RNA, extensive sequencing and mathematical modeling. Transcriptional activation correlated with the highest increases in Myc binding at promoters. Repression followed a reciprocal scenario, with the lowest gains in Myc binding. Altogether, the relative abundance (henceforth, “share”) of Myc at promoters was the strongest predictor of transcriptional responses in diverse cell types, predominating over Myc's association with the co-repressor Miz1. Myc activation elicited immediate loading of RNAPII at activated promoters, followed by increases in pause-release5, while repressed promoters showed opposite effects. Gains and losses in RNAPII loading were proportional to the changes in the Myc share, suggesting that repression by Myc may be largely indirect, owing - at least in part - to competition for limiting amounts of RNAPII. Secondary to the changes in RNAPII loading, the dynamics of elongation and pre-mRNA processing were also rapidly altered at Myc regulated genes, leading to the transient accumulation of partially or aberrantly processed mRNAs. Altogether, our results shed light on how over-expressed Myc alters the various phases of the RNAPII cycle and the resulting transcriptional response. Overall design: Time course profiling of 4sU-labeled and total RNA upon Myc activation in 3T9-MycER mouse fibroblasts
Integrative analysis of RNA polymerase II and transcriptional dynamics upon MYC activation.
Specimen part, Subject
View SamplesFrankincense oil is prepared from aromatic hardened wood resin obtained by tapping Boswellia trees. For thousands of years, it has been important both socially and economically as an ingredient in incense and perfumes. Frankincense oil is a botanical oil distillate made from fermented plants that contains boswellic acid, a component known to have anti-neoplastic properties. We evaluated frankincense oil-induced cytotoxicity in bladder cancer cells. With a window of concentration, frankincense oil suppressed cell viability and induced cytotoxicity in bladder transitional carcinoma J82 cells but not normal bladder urothelial UROtsa cells immortalized with SV40 large T antigen. However, frankincense oil-induced J82 cell death did not result in DNA fragmentation. Microarray and bioinformatics analysis confirmed that frankincense oil activated cell cycle arrest, suppressed cell proliferation, and activated apoptosis in J82 cells through a series of potential pathways. These finding suggest that bladder cancer can be treated through intravesical administration of pharmaceutical agents similar to direct application on melanoma.
Frankincense oil derived from Boswellia carteri induces tumor cell specific cytotoxicity.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
MYC regulates the core pre-mRNA splicing machinery as an essential step in lymphomagenesis.
Specimen part, Treatment
View SamplesOver-expressed MYC binds to virtually all active promoters within a cell, although with different binding affinities, and modulates gene expression, both positively and negatively. Here, we show that during lymphomagenesis in E-myc transgenic mice, MYC directly up-regulates the transcription of the core snRNP assembly genes, including PRMT5, an arginine methyltransferase, that methylates Sm proteins as an early step in lymphomagenesis. This coordinated regulatory effect is direct and is critical for snRNP biogenesis, the maintenance of effective mRNA splicing and cellular viability in cycling cells, in either fibroblasts or B-cells.
MYC regulates the core pre-mRNA splicing machinery as an essential step in lymphomagenesis.
Specimen part
View SamplesDeep sequencing has revealed that epigenetic modifiers are the most mutated genes in acute myeloid leukemia (AML). Thus, elucidating epigenetic dysregulation in AML is crucial to understand disease mechanisms. Here, we demonstrate that Metal Response Element Binding Transcription Factor 2/Polycomblike 2 (MTF2/PCL2) plays a fundamental role in the Polycomb repressive complex 2 (PRC2) and that its loss elicits an altered epigenetic state underlying refractory AML. Unbiased systems analyses identified the loss of MTF2-PRC2 repression of MDM2 as central to, and therefore a biomarker for, refractory AML. Thus, immature MTF2- deficient CD34+CD38- cells overexpress MDM2, thereby inhibiting p53 that leads to chemoresistance due to defects in cell cycle regulation and apoptosis. Targeting this dysregulated signaling pathway by MTF2 overexpression or MDM2 inhibitors sensitized refractory patient leukemic cells to induction chemotherapeutics and prevented relapse in AML patient-derived xenograft (PDX) mice. Therefore, we have uncovered a direct epigenetic mechanism by which MTF2 functions as a tumor suppressor required for AML chemotherapeutic sensitivity and identified a potential therapeutic strategy to treat refractory AML. Overall design: Fold change analysis between treatment and control
Targeting the MTF2-MDM2 Axis Sensitizes Refractory Acute Myeloid Leukemia to Chemotherapy.
Specimen part, Subject
View SamplesWe have identified candidate genes from the Feml2 QTL influencing femur length through allele specific expression analysis of growth plates in C57BL/6J x CAST/EiJ F1 hybrids. This work provides the foundation to identify novel genes affecting bone geometry. Overall design: total RNA sequencing in 7 male C57BL/6JxCAST F1s
Genetic Dissection of a QTL Affecting Bone Geometry.
Sex, Age, Specimen part, Cell line, Subject
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