Project description:This SuperSeries is composed of the following subset Series: GSE39356: MiR-374a Promotes Epithelial-Mesenchymal Transition (EMT) and Metastasis of Breast Cancer (mRNA dataset) GSE39358: MiR-374a Promotes Epithelial-Mesenchymal Transition (EMT) and Metastasis of Breast Cancer (miRNA dataset) Refer to individual Series
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:The biological process termed Epithelial-to-Mesenchymal Transition (EMT) plays a central role in cancer cell invasion, metastasis, self-renewal and resistance to therapy. Here, we characterize using quantitative LC-MS/MS the global changes in proteins levels occurring during EMT induced by epidermal growth factor in breast cancer MDA-MB-468 cells.
Project description:Breast cancer is one of the leading causes of death in females, mainly because of metastasis. Oncometabolites, produced via metabolic reprogramming, can influence metastatic signaling cascades. Accordingly, and based on our previous results, we hypothesized that metabolites from highly metastatic breast cancer cells behave differently from less-metastatic cells and may play a significant role in metastasis. We treated the less metastatic cells (MCF-7) with metabolites secreted from highly metastatic cells (MDA-MB-231) and the gene expression of three epithelial-to-mesenchymal transition (EMT) markers including E-cadherin, N-cadherin and vimentin were examined. Some metabolites secreted from MDA-MB-231 cells significantly induced EMT activity. Specifically, hypoxanthine demonstrated significant EMT effect and increased the migration and invasion effects of MCF-7 cells through a hypoxia-associated mechanism. Hypoxanthine exhibited pro-angiogenic effects and increased the lipid metabolism. Notably, knockdown of purine nucleoside phosphorylase (PNP), a gene encoding for an important enzyme in the biosynthesis of hypoxanthine, and inhibition of hypoxanthine uptake caused a significant decrease in hypoxanthine-associated EMT effects. Collectively for the first time, hypoxanthine was identified as a novel metastasis-associated metabolite in breast cancer cells and represents a promising target for diagnosis and therapy.
Project description:Epithelial-to-mesenchymal transition (EMT) is a developmentally conserved cell biological program adopted by cancer cells to metastasize to different organs. In this process, compact, cobblestone-shaped epithelial cells transform into more slender-shaped mesenchymal cells. Throughout metastasis, cells reside at various stages along the E-M spectrum. Epithelial cells are not necessarily converted to mesenchymal cells, as cells in the E-M continuum exhibit greater survival advantages and better metastatic ability than complete mesenchymal forms. During metastasis, epithelial cells traverse through narrow capillaries, inducing nucleus rupture. The nucleus is protected by type V intermediate filament proteins, Lamins, in the inner nuclear membrane, providing structural integrity, facilitating genome organization, and acting as an impediment to cell migration. Therefore, Lamin expression is downregulated to facilitate nuclear compliance during EMT, serving as a precursor for metastasis. Here, we aim to address the mechanism of Lamin downmodulation and its role in genome organization during EMT. We have attempted to address these questions in three independent and well-established breast cancer cell lines representing cells at specific stages of the EM spectrum, providing a paradigm to elucidate the role of Lamins in genome organization and function during EMT.
Project description:Cancer cells undergo transcriptional reprogramming to drive tumor progression and metastasis. Here, we identified the transcriptional complex, NELF (Negative elongation factor), as an important regulator of this process. Using cancer cell lines and patient-derived tumor organoids, we demonstrated that loss of NELF inhibits breast cancer tumorigenesis and metastasis. Specifically, we found that epithelial-mesenchymal transition (EMT) and stemness-associated genes are downregulated in NELF-depleted breast cancer cells. Quantitative Multiplexed Rapid Immunoprecipitation Mass spectrometry of Endogenous proteins (qPLEX-RIME) of NELF-E, a key subunit of NELF, reveals significant rewiring of NELF-E-associated chromatin partners as a function of EMT, and further illuminates a co-option of NELF-E with the key EMT transcription factor SLUG. Accordingly, loss of NELF-E led to impaired SLUG binding on chromatin. Through integrative transcriptomic and genomic analyses, we identified the histone acetyltransferase, KAT2B, as a key functional target of NELF-E-SLUG. Genetic and pharmacological inactivation of KAT2B ameliorate expression of critical EMT marker genes, phenocopying NELF ablation. Elevated NELF-E and KAT2B expressions are associated with poorer prognosis in breast cancer patients, highlighting the clinical relevance of our findings. Importantly, KAT2B knockout mice are viable, raising the exciting prospect of targeting this dependency therapeutically. Taken together, we uncovered a crucial role of the NELF-E-KAT2B epigenetic axis in breast cancer carcinogenesis.
Project description:Inflammatory breast cancer (IBC) is a rare type of breast cancer but accounts for up to 10% of breast cancer-related deaths. Plasticity between epithelial and mesenchymal feature is reported to be crucial in metastasis of IBC. Using Matigel culture, we induced epithelial to mesenchymal transition (EMT) in epithelial-like SUM149 IBC cells and identified overexpressed genes in this EMT process.
Project description:The biological process termed Epithelial-to-Mesenchymal Transition (EMT) plays a central role in cancer cell invasion, metastasis, self-renewal and resistance to therapy(1,2). Here, using western blot technique, we show that H3K9me2 decreases when MDA-MB-468 breast cancer cells undergo EMT upon EGF. We validate this decrease by performing high-resolution MS/MS spectrum. Interestingly, we find that H3K9me2 is associated with mesenchymal genes regulation. 1. Nieto, M. A., Huang, R. Y., Jackson, R. A. & Thiery, J. P. EMT: 2016. Cell 166, 21–45 (2016). 2. Puisieux, A. & Brabletz, T. & Caramel, J. Oncogenic roles of EMT-inducing transcription factors. Nat. Cell Biol. 16, 488–494 (2014).
Project description:Epithelial to Mesenchymal Transition (EMT) renders epithelial cells to acquire migratory characteristics during development and cancer metastasis. While epigenetic and splicing changes have been implicated in EMT, the mechanisms governing their crosstalk remain poorly understood. Here, we identify C2H2 zinc finger protein, ZNF827, a novel factor, is strongly induced during important EMT mediated processes including in brain development and breast cancer metastasis and is required for the molecular and phenotypic changes underlying EMT in these processes. Mechanistically, ZNF827 mediated these responses by orchestrating a large-scale remodeling of the splicing landscape by recruiting HDAC1 for epigenetic modulation of distinct genomic loci, thereby slowing RNA Pol II progression and altering the splicing of transcripts encoding key EMT regulators in cis. These findings reveal an unprecedented complexity between epigenetic landscape and splicing and identifies ZNF827 as a master regulator coupling these processes during EMT in brain development and breast cancer metastasis.
Project description:Tumor metastasis remains the major cause of cancer-related death, but its molecular basis is still not well understood. Here we uncovered a splicing-mediated pathway that is essential for breast cancer metastasis. We show that the RNA-binding protein hnRNPM promotes breast cancer metastasis by activating the switch of alternative splicing that occurs during epithelial-mesenchymal transition (EMT). Genome-wide deep sequencing analysis suggests that hnRNPM potentiates TGFb signaling and identifies CD44 as a key downstream target of hnRNPM. hnRNPM ablation prevents TGFb-induced EMT and inhibits breast cancer metastasis in mice, whereas enforced expression of the specific CD44s splice isoform overrides the loss of hnRNPM and permits EMT and metastasis. Mechanistically, we demonstrate that the ubiquitously expressed hnRNPM acts in a mesenchymal-specific manner to precisely control CD44 splice isoform switching during EMT. This restricted cell-type activity of hnRNPM is achieved by competition with ESRP1, an epithelial-splicing regulator that binds to the same cis-regulatory RNA elements and is repressed during EMT. Importantly, hnRNPM is associated with aggressive breast cancer and correlates with increased CD44s in patient specimens. These findings demonstrate a novel molecular mechanism through which tumor metastasis is endowed by the hnRNPM-mediated splicing program. RNAseq for control, hnRNPM siRNA treated lung metastatic LM2 clonal line, derived from the mesenchymal MDA-MB-231 cells