Tumor growth and metastasis is controlled by paracrine signaling between cells of the tumor microenvironment and malignant cells. Cancer-associated fibroblasts (CAFs), are functionally important components of the tumor microenvironment. Although some steps involved in the cross-talk between these cells are known, there is still a lot that is not clear. Thus, the addition of, the consideration of microenvironment in the development of the disease, to the clinical and pathological procedures (currently admitted as the consistent value cancer treatments) could lay the foundations for the development of new treatment strategies to control the disease.
Functional heterogeneity of cancer-associated fibroblasts from human colon tumors shows specific prognostic gene expression signature.
Specimen part
View SamplesAlthough heterochromatin is enriched with repressive traits, it is also actively transcribed, giving rise to large amounts of non-coding RNAs. Although these RNAs are responsible for the formation and maintenance of heterochromatin, little is known about how their transcription is regulated. Here we show that the Snail1 transcription factor represses pericentromeric transcription, acting through the H3K4 deaminase LOXL2. Since Snail1 plays a key role in the epithelial to mesenchymal transition (EMT), we analyzed the regulation of mouse heterochromatin transcription in this process. At the onset of EMT, one of the major structural heterochromatin proteins, HP1a, is transiently released from heterochromatin foci in a Snail1/LOXL2dependent manner during EMT, concomitantly with a down-regulation of major satellite transcription. Global transcriptome analysis indicated that ectopic expression of heterochromatin transcripts affects the transcription profile of EMT-related genes. Additionally, preventing the down-regulation of major satellite transcripts compromised the migratory and invasive behavior of mesenchymal cells. We propose that Snail1 regulates heterochromatin transcription through the histone-modifying enzyme, LOXL2, thus creating the favorable transcriptional state necessary for completing EMT.
Regulation of heterochromatin transcription by Snail1/LOXL2 during epithelial-to-mesenchymal transition.
Cell line, Treatment
View SamplesGene expression from MDA-MB-231 cells shControl and shLOXL2.
Lysyl oxidase-like 2 (LOXL2) oxidizes trimethylated lysine 4 in histone H3.
Cell line
View SamplesSnail1 transcriptional factor is essential for triggering epithelial-to-mesenchymal transition (EMT) and inducing tumor cell invasion. We report here that Snail1 plays also a key role in tumor associated fibroblasts since is necessary for enhancement by these cells on epithelial cells tumor invasion. Snail1 expression in fibroblast requires signals derived from tumor cells such as TGF-b; reciprocally, in fibroblasts Snail1 organizes a complex program that favors collective invasion of epithelial cells at least in part by the secretion of diffusible signaling molecules, such as prostaglandin E2. The capability of human or murine tumor-derived cancer associated fibroblasts to promote tumor invasion is associated to Snail1 expression and obliterated by Snail1 depletion. In vivo experiments show that tumor cells co-transplanted with Snail1 depleted fibroblasts show lower invasion than those xenografted with control fibroblasts. Finally Snail1 depletion in mice prevents the formation of breast tumors and decreased their invasion. Therefore, these results demonstrate that the role of Snail1 in tumor invasion is not limited to its effect in EMT but dependent on its expression in stromal fibroblasts where it orchestrates its activation and the crosstalk with epithelial cells.
Snail1-Dependent Activation of Cancer-Associated Fibroblast Controls Epithelial Tumor Cell Invasion and Metastasis.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Suboptimal evolutionary novel environments promote singular altered gravity responses of transcriptome during Drosophila metamorphosis.
Sex, Age
View SamplesGenome-wide transcriptional profiling showed that reducing gravity levels in the International Space Station (ISS) causes important alterations in Drosophila gene expression intimately linked to imposed spaceflight-related environmental constrains during Drosophila metamorphosis. However, simulation experiments on ground testing space-related environmental constraints, show differential responses. Curiously, although particular genes are not common in the different experiments, the same GO groups including a large multigene family related with behavior, stress response and organogenesis are over represented in them. A global and integrative analysis using the gene expression dynamics inspector (GEDI) self-organizing maps, reveals different degrees in the responses of the transcriptome when using different environmental conditions or microgravity/hypergravity simulation devices
Suboptimal evolutionary novel environments promote singular altered gravity responses of transcriptome during Drosophila metamorphosis.
No sample metadata fields
View SamplesEpithelial tumors can progress from a benign tissue overgrowth (hyperplasia) to a malignant neoplastic tumor, which is characterized by an increase in motility and invasiveness. The Cohen laboratory has developed an epithelial tumor model in which overexpression of the epidermal growth factor receptor gene (EGFR) leads to benign tissue hyperplasia. When combined with other cooperating factors, EGFR overexpression can lead to neoplasia and malignant metastasis.
Warburg Effect Metabolism Drives Neoplasia in a Drosophila Genetic Model of Epithelial Cancer.
Specimen part, Time
View SamplesNOTCH1 is mutationally activated in ~15% of cases of chronic lymphocytic leukaemia (CLL), but its role in B-cell development and leukemogenesis is not known. Here, we report that the active intracellular portion of NOTCH1 (ICN1) is detectable in ~50% of peripheral blood CLL cases lacking gene mutations. We identify a ‘NOTCH1 CLL gene expression signature’ in CLL cells, and show that this signature is significantly enriched in primary CLL cases expressing ICN1, independent of NOTCH1 mutation. NOTCH1 target genes include key regulators of B-cell proliferation, survival and signal transduction physiology. In particular, we show that MYC is a direct target of NOTCH1 via B-cell specific distal regulatory elements, thus implicating this oncogene in the pathogenesis of the disease. Overall design: RNA-Seq analysis
Common nonmutational <i>NOTCH1</i> activation in chronic lymphocytic leukemia.
Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Metabolic reprogramming induces resistance to anti-NOTCH1 therapies in T cell acute lymphoblastic leukemia.
Specimen part
View SamplesTo investigate the underlying mechanisms mediating resistance to NOTCH inhibition in Pten-null T-ALL tumor cells we performed gene expression profiling of isogenic Pten-positive and Pten-deleted leukemia lymphoblasts after acute treatment with DBZ in vivo.
Metabolic reprogramming induces resistance to anti-NOTCH1 therapies in T cell acute lymphoblastic leukemia.
Specimen part
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