Project description:This SuperSeries is composed of the following subset Series: GSE27968: DNA methylation data from AML12 cells during EMT GSE28291: Genome-scale epigenetic reprogramming during epithelial to mesenchymal transition Refer to individual Series
Project description:Epithelial-mesenchymal transition (EMT) involves profound changes in cell morphology, driven by transcriptional and epigenetic reprogramming. However, it emerges that translation and the ribosome composition play also key role in establishing physio-pathological phenotypes. Using genome-wide analyses, we report significant rearrangement of the translational landscape and machinery during EMT. Specifically, a mesenchymal cell line overexpressing the EMT transcription factor ZEB1 shows alterations in translational reprogramming and fidelity. Considering the change in translational activity of ZEB1-overexpressing mesenchymal cells, including in fidelity activity, we sought for changes in ribosome composition. We thus performed a riboproteome approach, i.e., mass spectrometry (MS)-based quantitative proteomic analysis of purified cytoplasmic ribosomes to highlight any change in relative amount of individual ribosomal proteins between wild-type and ZEB1-overexpressing human mammary epithelial cells.
Project description:Epithelial to Mesenchymal Transition (EMT) has been associated with cancer cell heterogeneity, plasticity and metastasis. It has been the subject of several modeling effort. This logical model of the EMT cellular network aims to assess microenvironmental signals controlling cancer-associated phenotypes amid the EMT continuum. Its outcomes relate to the qualitative degrees of cell adhesions by adherent junctions and focal adhesions, two features affected during EMT. Model attractors recover epithelial, mesenchymal and hybrid phenotypes, and simulations show that hybrid phenotypes may arise through independent molecular paths, involving stringent extrinsic signals.
Of particular interest, model predictions and their experimental validations indicated that: 1) ECM stiffening is a prerequisite for cells overactivating FAK-SRC to upregulate SNAIL1 and acquire a mesenchymal phenotype, and 2) FAK-SRC inhibition of cell-cell contacts through the Receptor Protein Tyrosine Phosphates kappa leads to the acquisition of a full mesenchymal rather than a hybrid phenotype.
Project description:Tet1 is a hydroxylase known for its role in the conversion of 5-methylcytosines (5mC) to 5-hydroxymethylcytosines (5hmC) involved in the possible active demethylation process and gene expression regulation1-5.M-BM- As somatic cell reprogramming involves the re-activation of pluripotency genes and the silencing of somatic ones6, it remains unclear whether Tet1 plays a positive or negative role in the reprogramming process. Here we show that Tet1 deficiency enhances reprogramming and its overexpression impairs reprogramming. Mechanistically, we demonstrated that Tet1 represses the early obligatory process of mesenchymal to epithelial transition (MET) during reprogramming7,8. Thus, our findings not only define a negative role for Tet1 in somatic cell reprogramming, but also suggest that the Tet enzymes regulate cell fate through distinctive mechanisms. Examination of genome DNA hmC modifications in 2 conditions: individually overexpressed Tet1CD or Tet2CD during MEF reprogramming; Examination of mRNA levels in five different conditions: individually overexpressed DR or Tet1CD or Tet1CDmut or Tet2CD or Tet2CDmut, during MEF reprogrammig.
Project description:ES cell pluripotency is thought to be regulated in part by H3K4 methylation. However, it is unclear how H3K4 demethylation contributes to ES cell function and participates in iPS cell reprogramming. Here, we show that KDM5B, which demethylates H3K4, is important for ES cell differentiation, and presents a barrier to the reprogramming process. Depletion of Kdm5b leads to an extension in the self-renewal of ES cells in the absence of LIF. Transcriptome analysis revealed the persistent expression of pluripotency-genes and underexpression of developmental genes during differentiation in the absence of Kdm5b, suggesting that KDM5B plays a key role in cellular fate changes. We also observed accelerated reprogramming of differentiated cells in the absence of Kdm5b, demonstrating that KDM5B is a barrier to the reprogramming process. Expression analysis revealed that mesenchymal master regulators associated with epithelial-to-mesenchymal transition (EMT) are downregulated during reprogramming in the absence of Kdm5b. Moreover, global analysis of H3K4me3/2 revealed that enhancers of fibroblast genes are rapidly deactivated in the absence of Kdm5b, and genes associated with EMT lose H3K4me3/2 during the early reprogramming process. These findings provide functional insight into the role for KDM5B in regulating ES cell differentiation and as a barrier to the reprogramming process. ChIP-Seq for H3K4me3 and H3K4me2 in murine shLuc and shKdm5b 4TF-MEFs (tetO-Pou5f1,-Sox2,-Klf4,-c-Myc) at 48h.
Project description:We find that treating mesenchymal NAMEC8 cells with cholera toxin (CTx) to elevate intracellular cAMP levels and activate PKA induces a mesenchymal-to-epithelial transition whereby the cells assume an epithelial state (N8-CTx). NAMEC8 cells undergo epigenetic reprogramming triggered by active PHF2, a histone demethylase, which demethylates H3K9me2 and H3K9me3 regions of epithelial genes silencing in the mesenchymal state
Project description:Primary objectives: Evaluate the effect of the imipramine treatment on the development of histological manifestations associated with the mesenchymal epithelial transition during the period of time from the analysis of the diagnostic biopsy to the surgical resection intervention.
Primary endpoints: Comparison of the histological traits of invasive tumour front of the surgical tumour resection specimen between the intervention group and the placebo group:1. Fascin1 expression in tumour tissue: It will be analysed by immunohistochemistry and the application of Immunoscore.2. Histological manifestations of the epithelial-mesenchymal transition (EMT): Tumour budding, cytoplasmic pseudo-fragments, infiltrating growth pattern and poorly differentiated nests. It will be evaluated by histological analysis.3. Invasive histological manifestations: discontinuous extramural extension, lymphatic, venous and perineural infiltration. It will be evaluated by histological analysis.4. Histological manifestation of the immune response: Peritumoral and intratumour lymphocyte infiltration. It will be evaluated by histological analysis.5. EMT molecular manifestations: FSCN1, SNAIL and SLUG gene expression. It will be evaluated by NGS analysis of the primary tumour.
Project description:Chromatin immunoprecipitation followed by Solexa sequencing for H3K27me3 and H3K79me2 in Fibroblasts, Embryonic stem cells, and fibroblast undergoing reprogramming Inhibition of the histone 3 lysine 79 (H3K79) methyltransferase increases repgoramming efficiency and genome-wide analysis of H3K79me2 distribution revealed that fibroblast-specific genes associated with the epithelial to mesenchymal transition lose H3K79me2 in the initial phases of reprogramming. Dot1L inhibition facilitates the loss of this mark from genes that are fated to be repressed in the pluripotent state.