Project description:Endothelial-mesenchymal transition (EndMT) is a complex process, in which differentiated endothelial cells undergo phenotypic transition to mesenchymal cells. Given the diversity of the vascular system in architecture, structure, and embryonic origins, it is not clear if endothelial cells lining different vessels are able to undergo EndMT. Therefore, the aim of this study was to evaluate the molecular and functional changes that occur in different types of endothelial cells after induction of EndMT through overexpression of Snail and TGF-β2. Different types of endothelial cells (human umbilical vein, heart, and lung) have distinct response when induced to undergo EndMT. Coronary artery endothelial cells (HCAEC) induced with combined Snail overexpression plus TGF-β2 treatment promotes a decrease of endothelial markers, an increase of mesenchymal markers and migration. The mechanism that HCAEC undergoing EndMT may be mediated through Notch and non-canonical Wnt signaling pathways. These results provide the foundation for understanding the roles of specific signaling pathways in mediating EndMT in endothelial cells from different anatomical origin.
Project description:Endothelial-to-mesenchymal transition (EndMT) is a dynamic transformation process that has a functional impact upon pathological vascular remodelling. However, the molecular mechanisms that govern EndMT remain largely unknown. We modelled this process in vitro by exposing human primary endothelial cells to a combination of transforming growth factor-β2 (TGF- β2) and interleukin-1β (IL-1β). RNAseq was carried out to analyse the change of gene expression during the transition and define the transcriptional architecture of EndMT.
Project description:m6A-mRNA&lncRNA Epitranscriptomic Microarray of primary mouse RPE cells comparing control untreated RPE cells with RPE cells treated with TGF-β2 at a concentration of 10 ng/ml. The goal was to determine the effects of RNA m6a methylation on primary mouse RPE cells undergoing epithelial-mesenchymal transition induced by TGF-β2.
Project description:Prostate cancer often progresses to castration-resistant prostate cancer (CRPC), with neuroendocrine prostate cancer (NEPC) representing a highly aggressive variant. This study shows that endothelial-to-mesenchymal transition (EndMT) in vascular endothelial cells, induced by IL-1β and TGF-β2, enhances neuroendocrine differentiation in prostate cancer cells. LNCaP cells co-cultured with EndMTed HUVECs exhibited increased expression of neuroendocrine markers such as chromogranin A. GM-CSF emerged as a key mediator in this process, and its addition under androgen deprivation conditions further elevated neuroendocrine marker expression. Anti-androgen therapy with enzalutamide also paradoxically increased IL-1β and TGF-β2 secretion, promoting EndMT and subsequent neuroendocrine differentiation. These results highlight the potential of targeting EndMT and GM-CSF pathways as therapeutic strategies for aggressive, treatment-resistant forms of NEPC.
Project description:Extracellular pH (pHe) is lower in many tumors than in the corresponding normal tissue. Acidic tumor microenvironment has been shown to facilitate epithelial mesenchymal transition (EMT) and tumor metastasis, while the mechanisms underlying tumor acidic microenvironment-induced tumor cell metastasis remain undefined. Here, we aimed to investigate the tumor metastasis and the EMT by acidic microenvironment and to explore their mechanisms and clinical significance in lung cancer. Results showed that acidic pHe remarkably enhanced invasion ability of lung cells accompanying with increased mesenchymal and decreased epithelial markers. Moreover, acidic pHe triggered the inhibition of microRNA-7 (miR-7) expression and activation of TGF-β2/SMAD signaling. Mechanistic studies showed that TGF-β2 is a direct potential target gene of miR-7, and acidity-induced metastasis could be abolished by treatment with a TGFβRI inhibitor, anti-TGF-β2 antibody and miR-7 mimic, respectively. The clinical samples further revealed that miR-7 was decreased in lung tissues and antagonistically correlated with TGF-β2 expression, associating with overall survival and metastasis. In conclusion, our study indicated that acidic pHe showed enhanced invasive potential, and enhanced potential to develop experimental metastases by a novel mechanism involving tumor acidic microenvironment-induced regulation of miR-7/TGF-β2/SMAD axis. Our findings suggest that the possibility that pHe of the primary tumor may be an important prognostic parameter for lung cancer patients merit clinical investigation. Moreover, miR-7 may serve as prognostic molecular marker and a novel therapeutic target for lung cancer.
Project description:Endothelial-to-mesenchymal transition (EndMT) is a dynamic biological process involved in pathological vascular remodeling. However, the molecular mechanisms that govern this transition remain largely unknown. To study EndMT in vitro, human umbilical vein endothelial cells (HUVEC) were treated with transforming growth factor-β2 and interleukin-1β, leading to a decrease of endothelial markers as well as an increase of mesenchymal markers and EndMT regulators after 7 days. Single-cell RNA-seq was carried out to study the dynamics of the transition.
Project description:Endothelial-to-mesenchymal transition (EndMT) is a dynamic transformation process that has a functional impact upon pathological vascular remodelling. The molecular mechanisms that govern EndMT remain largely unknown. By induction of EndMT in human primary endothelial cells (EC), using a combination of transforming growth factor-β2 (TGF-b2) and interleukin-1b (IL-1β), we identified the dramatic loss of the lncRNA MIR503HG, as a common signature across multiple primary EC types. Targeted depletion of MIR503HG spontaneously induced EndMT. Overexpression of MIR503HG repressed EndMT despite TGF-β2 and IL-1β co-stimulation. RNA-seq was carried out to identify the changes in gene expression induced by MIR503HG overexpression. We showed that over 25% of the EndMT-transcriptome signature was inhibited upon MIR503HG overexpression. Crucially, phenotypic changes induced by MIR503HG were independent of the functional regulation of miR-503 and miR-424, both harbored within the MIR503HG locus. Collectively, we identify the lncRNA MIR503HG as an essential regulator of EndMT.
Project description:Endothelial cells play an important role in maintenance of the vascular system and the repair after injury. Under pro-inflammatory conditions, endothelial cells can acquire a mesenchymal phenotype by a process named endothelial-to-mesenchymal transition (EndMT), which affects the functional properties of endothelial cells. Here, we investigated the epigenetic control of EndMT. We show that the histone demethylase JMJD2B is induced by EndMT promoting pro-inflammatory and hypoxic conditions. Silencing of JMJD2B reduced TGF-β2-induced expression of mesenchymal genes and prevented the alterations in endothelial morphology and impaired endothelial barrier function. Endothelial-specific deletion of JMJD2B in vivo confirmed a reduction of EndMT after myocardial infarction. EndMT did not affect global H3K9me3 levels but induced a site-specific reduction of repressive H3K9me3 marks at promoters of mesenchymal genes, such as Calponin (CNN1), and genes involved in TGF-β signaling, such as AKT Serine/Threonine Kinase 3 (AKT3) and sulfatase 1 (SULF1). Silencing of JMJD2B prevented the EndMT-induced reduction of H3K9me3 marks at these promotors and further repressed these EndMT-related genes. Our study reveals that endothelial identity and function is critically controlled by the histone demethylase JMJD2B, which is induced by EndMT-promoting pro-inflammatory and hypoxic conditions and support the acquirement of a mesenchymal phenotype.
Project description:Endothelial cells play an important role in maintenance of the vascular system and the repair after injury. Under pro-inflammatory conditions, endothelial cells can acquire a mesenchymal phenotype by a process named endothelial-to-mesenchymal transition (EndMT), which affects the functional properties of endothelial cells. Here, we investigated the epigenetic control of EndMT. We show that the histone demethylase JMJD2B is induced by EndMT promoting pro-inflammatory and hypoxic conditions. Silencing of JMJD2B reduced TGF-β2-induced expression of mesenchymal genes and prevented the alterations in endothelial morphology and impaired endothelial barrier function. Endothelial-specific deletion of JMJD2B in vivo confirmed a reduction of EndMT after myocardial infarction. EndMT did not affect global H3K9me3 levels but induced a site-specific reduction of repressive H3K9me3 marks at promoters of mesenchymal genes, such as Calponin (CNN1), and genes involved in TGF-β signaling, such as AKT Serine/Threonine Kinase 3 (AKT3) and sulfatase 1 (SULF1). Silencing of JMJD2B prevented the EndMT-induced reduction of H3K9me3 marks at these promotors and further repressed these EndMT-related genes. Our study reveals that endothelial identity and function is critically controlled by the histone demethylase JMJD2B, which is induced by EndMT-promoting pro-inflammatory and hypoxic conditions and support the acquirement of a mesenchymal phenotype.
Project description:Cancer stem cells (CSCs) are proposed to be responsible for metastatic dissemination and clinical relapse in a variety of cancers. Analogies between CSCs and normal tissue stem cells (SC) has led to the notion that CSCs often co-opt the normal SC program of their tissue-of-origin. The cell-biological program termed epithelial-mesenchymal transition (EMT) has been found to encourage entrance of normal and neoplastic mammary cells into the corresponding SC states. Using genetically engineered knock-in reporter mouse lines, we demonstrate that in the murine mammary lineage, the paralogous EMT-inducing transcription factors Snail and Slug, are selectively exploited by CSCs and normal SCs respectively. Slug, when expressed at physiological levels, only activates a partial EMT program and is dispensable in CSCs. In contrast, Snail drives a far more complete transition into the mesenchymal state and controls both tumor-initiation and metastatic dissemination. Consistent with their functional distinctions, Snail controls far more target genes than Slug, and their distinct functions are determined by their divergent N-terminal domains. Our findings underscore fundamental distinctions between the SC program operating in normal and neoplastic SCs, and hint for potential avenues of selective therapeutic elimination of breast CSCs. We sought to understand differential ability to activate the EMT program in breast cancer cells by transcription factors Snail and Slug. Hence, we mapped genome-wide Snail and Slug binding sites in murine MMTV-PyMT breast cancer cell lines that express high level of Snail or high level of Slug respectively. Specifically, we performed Snail ChIP seq in the mesenchymal pBl.3G cells, and Slug ChIP-seq in the epithelial pBl.1G cells.