Project description:Orphan nuclear receptor chicken ovalbumin upstream promoter transcription factor 2 (COUPTF2; NR2F2) is highly expressed in endothelial cells (ECs) and Nr2f2 knockout produces lethal cardiovascular defects. In humans, NR2F2 mutations result in both congenital heart disease and diaphragmatic hernia, conditions associated with the development of pulmonary arterial hypertension (PAH). However, COUPTF2 functions in mature endothelium are uncertain. NR2F2 knockdown in primary human endothelial cells (ECs) led to an interferon-biased inflammatory response, endothelial-to-mesenchymal transition, proliferation, hypermigration, apoptosis-resistance and mitochondrial dysfunction. These phenotypic changes were associated with AKT activation and increased Dickkopf-1 (DKK1) expression, a Wnt/β-catenin pathway inhibitor. DKK1 was also elevated in patients with PAH and secreted in response to loss of bone morphogenetic receptor type 2 (BMPR2), the archetypal PAH-associated genetic defect. Together, these findings demonstrate that endothelial NR2F2 suppresses inflammation and proliferation. Thus, NR2F2 loss disrupts EC homeostasis and may promote pathologic vascular remodeling in the development of PAH.
Project description:Orphan nuclear receptor chicken ovalbumin upstream promoter transcription factor 2 (COUPTF2; NR2F2) is highly expressed in endothelial cells (ECs) and Nr2f2 knockout produces lethal cardiovascular defects. In humans, NR2F2 mutations result in both congenital heart disease and diaphragmatic hernia, conditions associated with the development of pulmonary arterial hypertension (PAH). However, COUPTF2 functions in mature endothelium are uncertain. NR2F2 knockdown in primary human endothelial cells (ECs) led to an interferon-biased inflammatory response, endothelial-to-mesenchymal transition, proliferation, hypermigration, apoptosis-resistance and mitochondrial dysfunction. These phenotypic changes were associated with AKT activation and increased Dickkopf-1 (DKK1) expression, a Wnt/β-catenin pathway inhibitor. DKK1 was also elevated in patients with PAH and secreted in response to loss of bone morphogenetic receptor type 2 (BMPR2), the archetypal PAH-associated genetic defect. Together, these findings demonstrate that endothelial NR2F2 suppresses inflammation and proliferation. Thus, NR2F2 loss disrupts EC homeostasis and may promote pathologic vascular remodeling in the development of PAH.
Project description:Orphan nuclear receptor chicken ovalbumin upstream promoter transcription factor 2 (COUPTF2; NR2F2) is highly expressed in endothelial cells (ECs) and Nr2f2 knockout produces lethal cardiovascular defects. In humans, NR2F2 mutations result in both congenital heart disease and diaphragmatic hernia, conditions associated with the development of pulmonary arterial hypertension (PAH). However, COUPTF2 functions in mature endothelium are uncertain. NR2F2 knockdown in primary human endothelial cells (ECs) led to an interferon-biased inflammatory response, endothelial-to-mesenchymal transition, proliferation, hypermigration, apoptosis-resistance and mitochondrial dysfunction. These phenotypic changes were associated with AKT activation and increased Dickkopf-1 (DKK1) expression, a Wnt/β-catenin pathway inhibitor. DKK1 was also elevated in patients with PAH and secreted in response to loss of bone morphogenetic receptor type 2 (BMPR2), the archetypal PAH-associated genetic defect. Together, these findings demonstrate that endothelial NR2F2 suppresses inflammation and proliferation. Thus, NR2F2 loss disrupts EC homeostasis and may promote pathologic vascular remodeling in the development of PAH.
Project description:Gene expression profiles of primary lymphatic endothelial cells (LECs) isolated from human foreskin were analyzed after siRNA-mediated knockdown of control (firefly luciferase), Prox1, NR2F2 or Prox1/NR2F2 for 48 hours. Experiment Overall Design: Passage five human lymphatic endothelial cells (LECs) were cultured on fibronectin (10 μg/ml)-coated plates in a complete media (EBM, 20% FBS supplemented with 10 μg/ml hydrocortisone acetate, 25 ug/ml cAMP and antibiotics). LECs were harvested and electorporated with siRNA duplexes for 48 hours with siRNA duplexes against either firefly luciferase(control), Prox1, NR2F2 or Prox1/NR2F2. Total RNA was purified using Tri-reagent and was subjected to microarray analysis. Experiment Overall Design:
Project description:Melanoma is a highly metastatic tumor type responsible of the large majority of the skin cancer-related deaths. Melanoma cells recapitulate the migratory and invasive nature of neural crest stem cells from which melanocytes arise. However, the mechanisms by which these developmental programs confer melanoma cells with more aggressive properties are not understood. Here we provide evidence for an epigenetically regulated developmental program that is aberrantly re-activated by melanoma cells to aid in the metastatic process. We reasoned that studying molecular changes occurring during the ontogeny of melanocytes from progenitor neural crest cells (NCC), and identifying developmental programs retained or re-gained by melanoma cells, could reveal crucial processes that modulate melanoma aggressiveness. Here we describe a novel mechanism that controls the activity of a transcriptional regulator of human neural crest, the Nuclear Receptor Subfamily 2 Group F, Member 2 (NR2F2). We find that highly localized DNA methylation acts as an on/off switch that controls the expression of a truncated NR2F2 isoform (NR2F2-Iso2) from an alternative transcription start site during NCC to melanocyte differentiation. We show that melanoma cells co-opt this developmental program by decreased DNA methylation and re-expression of NR2F2-Iso2 to promote melanoma metastasis. NR2F2-Iso2 regulates the transcriptional activity of the full length NR2F2 isoform 1 by impairing its binding to chromatin, which results in altered expression of NCC and differentiation genes. Our data demonstrate that epigenetic reactivation of NR2F2 isoform 2 promotes melanoma metastasis, which could be targeted for therapeutic purposes.
Project description:The Alternative Lengthening of Telomeres (ALT) facilitates telomere lengthening by a DNA strand invasion and copying mechanism. The nuclear receptor NR2F2 can bind to (TCAGGG)n variant repeats within telomeres and it has been proposed that this facilitates telomere interactions in ALT+ cells. However, the role NR2F2 in regulation the gene expression in ALT+ cell lines is unclear. Here, using Next Generation Sequencing (NGS), we characterised the changes in expression profile of three ALT+ cell lines (W-V, WI38VA13/2RA, U2OS) upon transient siRNA mediated downregulation of NR2F2 compared to cells treated with a control siRNA . Among 86 ALT-associated genes, only MND1 showed consistent down-regulation across the three NR2F2-depleted ALT+ cell lines. Altogether our data indicate that NR2F2 it does not play a direct role in the ALT mechanism.