Evi1 is essential for proliferation of hematopoietic stem cells and implicated in the development of myeloid disorders. Particularly, high Evi1 expression defines one of the largest clusters in acute myeloid leukemia and is significantly associated with extremely poor prognosis. Improvement of the therapeutic outcome of leukemia with activated Evi1 is one of the most challenging issues. However, mechanistic basis of Evi1-mediated leukemogenesis has not been fully elucidated. Here we show that Evi1 directly represses PTEN transcription in the murine bone marrow, which leads to activation of AKT/mTOR signaling. In a murine bone marrow transplantation model, Evi1 leukemia showed remarkable sensitivity to an mTOR inihibitor rapamycin. Furthermore, we found that Evi1 binds to several polycomb group proteins and recruits polycomb repressive complexes for PTEN downregulation, which reveals a novel epigenetic mechanism of AKT/mTOR activation in leukemia. Expression analyses and chromatin immunoprecipitation assays using human samples indicate that our findings in mice models are recapitulated in human leukemic cells. Dependence of Evi1-expressing leukemic cells on AKT/mTOR signaling provides the first example of targeted therapeutic modalities that suppress the leukemogenic activity of Evi1. The PTEN/AKT/mTOR signaling pathway and the Evi1-polycomb interaction can be promising therapeutic targets for leukemia with activated Evi1.
Evi1 represses PTEN expression and activates PI3K/AKT/mTOR via interactions with polycomb proteins.
Specimen part, Treatment
View SamplesThermal injury incites inflammatory responses that often transcend the local environment and lead to structural deficiencies in skin that give way to scar formation. We hypothesized that extensive perturbations within burned skin following thermal insult and during subsequent events of wound repair induce vast alterations in gene expression that likely serve as a wound and systemic healing deterrent. A high-throughput microarray experiment was designed to analyze genetic expression patterns and identify potential genes to target for therapeutic augmentation or silencing. The study compares gene expression from burn wound margins at various times following thermal injury to expression observed in normal skin. Utilizing this design, we report that the totality of gene expression alterations is indeed enormous. Further, we observed that the differential expression of many inflammatory and immune response genes appear to be continually up-regulated in burn wound margins seven days or more after initial thermal insult. As it is well established that the inflammatory process must abate for wound healing to proceed, the finding of ongoing local inflammation is cause for further investigation. To our knowledge, this is the first report of the gene expression alterations induced by thermal injury of human skin. As such, it provides a wealth of data to mine with the ultimate goal of better understanding the local pathophysiologic changes at the site of thermal injury that not only affect wound healing capacity, but may also contribute to systemic derangements within the burn patient.
A microarray analysis of temporal gene expression profiles in thermally injured human skin.
Sex
View SamplesGlucocorticoids (GCs) are essential steroid hormones that regulate the immune system. GCs have been widely used to treat various inflammation disorders and auto-immune diseases, due to their potent immune repression properties. Overall design: HeLa cells were cultured with DMEM plus 10% charcoal-stripped FBS. HeLa cells were treated in the presence of 100 nM triamcinolone acetonide (TA) for 4 hours. Cells were then collected for RNA-seq.
Extensive epigenomic integration of the glucocorticoid response in primary human monocytes and in vitro derived macrophages.
Cell line, Treatment, Subject
View SamplesGlucocorticoids (GCs) are essential steroid hormones that regulate the immune system. GCs have been widely used to treat various inflammation disorders and auto-immune diseases, due to their potent immune repression properties. Overall design: Monocytes from healthy donors were cultured in the presence of 100 nM triamcinolone acetonide (TA), 100 nM Dexamethasone (Dex) or 100 nM Prednisolone (Pred) for 4 hours. Cells were then collected for RNA-seq.
Extensive epigenomic integration of the glucocorticoid response in primary human monocytes and in vitro derived macrophages.
Specimen part, Disease, Treatment, Subject
View SamplesCHD4 is an ATPase able to use the energy from ATP to shift or remove nucleosomes from specific sites in the chromatin, thereby affecting accessability of gene regulatory elements. It is part of the NuRD complex.
Helicase CHD4 is an epigenetic coregulator of PAX3-FOXO1 in alveolar rhabdomyosarcoma.
No sample metadata fields
View SamplesAt present, medical treatments of synchronous and metachronous liver metastases from colorectal cancer are not differentiated. The aim of the study was to analyze the gene expression profiling of synchronous and metachronous lesions in order to identify molecular signatures as possible basis for choice of systemic therapies. Fresh tissues specimens from metastases of 18 patients undergone liver surgery were collected (10 synchronous and 8 metachronous lesions). Gene expression profiling was studied using Affymetrix platform. Two different profiles were identified. Pathway related to the Epidermal Growth Factor receptor (EGFr) was upregulated in metachronous lesions whereas pathways mainly related to inflammation in synchronous lesions. Real Time-PCR, Western Blotting and ELISA confirmed that the metachronous lesions had the overexpression of EGFr, but the synchronous ones had the overexpression of Cyclo-oxygenase 2 (COX-2). These results suggest that synchronous or metachronous liver metastases from colorectal cancer could be differently treated on the basis of different molecular pathways.
Gene expression profiling of liver metastases from colorectal cancer as potential basis for treatment choice.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A molecular portrait of gastrointestinal stromal tumors: an integrative analysis of gene expression profiling and high-resolution genomic copy number.
Sex, Age, Specimen part
View SamplesIn addition to KIT and PDGFRA mutations, sequential accumulation of other genetic events is involved in the development and progression of gastrointestinal stromal tumors (GISTs). Until recently, the significance of these other alterations has not been thoroughly investigated. The combination of gene expression profiling and high-resolution genomic copy number analysis offers a detailed molecular portrait of GISTs, providing an essential comprehensive knowledge necessary to guide the discovery of novel target genes involved in tumor development and progression.
A molecular portrait of gastrointestinal stromal tumors: an integrative analysis of gene expression profiling and high-resolution genomic copy number.
Sex, Age, Specimen part
View SamplesFour vehicle-treated and four HhAntag-treated pancreatic xenograft tumors were profiled for gene expression changes using Affymetrix U133 Plus 2.0 and Affymetrix Mouse Genome 430 2.0 arrays.
A paracrine requirement for hedgehog signalling in cancer.
No sample metadata fields
View SamplesCanonical Hedgehog (Hh) signaling regulates the expression of genes that are critical to the patterning and development of a variety of organ systems. In adult, both ligand-dependent and ligand-independent Hh pathway activation are known to promote tumorigenesis. Recent studies have shown that in tumors promoted by Hh ligand, activation occurs within the stromal microenvironment (Yauch et al., 2009). In situ hybridization of the pathway target gene, Ptch1, shows that signaling is located at stromal perivascular fibroblast-like cells in xenograft tumor sections derived from Hh-expressing colorectal cancer cell lines.
Canonical hedgehog signaling augments tumor angiogenesis by induction of VEGF-A in stromal perivascular cells.
Specimen part, Cell line, Treatment
View Samples