Project description:Esophageal cancer is one of the deadliest cancers as patients present at late stages of disease. Frequent gene alterations include the loss of E-cadherin and TGFb receptor type II. The goal of this study was to establish a model of esophageal cancer by introducing dominant-negative mutants of E-cadherin and TGFb receptor II. To analyze the functional consequences and gene expression chages induced by E-cadherin and TGFb receptor type II loss in esophageal cancer.
Project description:Esophageal cancer is one of the deadliest cancers as patients present at late stages of disease. Frequent gene alterations include the loss of E-cadherin and TGFb receptor type II. The goal of this study was to establish a model of esophageal cancer by introducing dominant-negative mutants of E-cadherin and TGFb receptor II. To analyze the functional consequences and gene expression chages induced by E-cadherin and TGFb receptor type II loss in esophageal cancer. Human esophageal keratinocytes were retrovirally transfected with wild-type full length E-cadherin, dominant-negative E-cadherin and dominant-negative TGFb receptor type II. Grown in organotypic cultures on a collagen/matrigel matrix with embedded fibroblast, the generated cell lines were analyzed for their potential to invade into the underlying matrix. Each cell lines was grown in duplicate in organotypic culture and therefore 2 replicates analyzed. Gene expression changes in invasive versus non-invasive areas were analyzed after RNA isolation using laser-capture microdissection resulting in 2 samples representing a normal esophageal epithelium (Ecad), 2 each of dominant-negative Ecad (Ecyto) non-invasive and invasive. To model the genetic alterations in esophageal cancer dominant-negative E-cadherin and dominant-negative TGFb receptor type II (Ecyto-dnTGFR) were expressed and 2 samples each, non-invasive and invasive, analyzed.
Project description:Pedro Vizán, Daniel S. J. Miller, Ilaria Gori, Debipriya Das, Bernhard Schmierer & Caroline S. Hill. Controlling long-term signaling: receptor dynamics determine attenuation and refractory behavior of the TGF-β pathway. Science Signaling 6, 305 (2013).
Understanding the complex dynamics of growth factor signaling requires both mechanistic and kinetic information. Although signaling dynamics have been studied for pathways downstream of receptor tyrosine kinases and G protein (heterotrimeric guanine nucleotide-binding protein)-coupled receptors, they have not been investigated for the transforming growth factor-β (TGF-β) superfamily pathways. Using an integrative experimental and mathematical modeling approach, we dissected the dynamic behavior of the TGF-β to Smad pathway, which is mediated by type I and type II receptor serine/threonine kinases, in response to acute, chronic, and repeated ligand stimulations. TGF-β exposure produced a transient response that attenuated over time, resulting in desensitized cells that were refractory to further acute stimulation. This loss of signaling competence depended on ligand binding, but not on receptor activity, and was restored only after the ligand had been depleted. Furthermore, TGF-β binding triggered the rapid depletion of signaling-competent receptors from the cell surface, with the type I and type II receptors exhibiting different degradation and trafficking kinetics. A computational model of TGF-β signal transduction from the membrane to the nucleus that incorporates our experimental findings predicts that autocrine signaling, such as that associated with tumorigenesis, severely compromises the TGF-β response, which we confirmed experimentally. Thus, we have shown that the long-term signaling behavior of the TGF-β pathway is determined by receptor dynamics, does not require TGF-β-induced gene expression, and influences context-dependent responses in vivo.
Project description:Recently, we found that a novel Traf2- and Nck-interacting kinase (TNIK) inhibitor, named NCB-0846, was capable of attenuating tumor-initiating cells among human colorectal cancer. The cross link between EMT and cancer stemness has been revealed in several studies and other group showed another TNIK inhibitor named KY-05009 had inhibited the TGF-β-induced EMT. Therefore we evaluated whether this small-molecule compound could have efficacy to inhibit TGF-β-induced EMT. NCB-0846 reduced the expression of mesenchymal markers (Vimentin and N-cadherin) and upregulated the expression of epithelial marker E-cadherin in A549 and H2228 non-small cell lung cancer cells. NCB-0846 suppressed the phosphorylation and nuclear translocation of Smad proteins and also inhibited migration, invasion, and metastasis. NCB-0846 inhibited TGF-β1-induced EMT through the down-regulation of TGF-β receptor-1 (TβRI) in mRNA levels. MiR-186-5p and miR-320 family were identified as candidate miRNAs that could target TβRI and we found that miR-186-5p and miR-320s inhibited TβRI expression. NCB-0846 might be a novel therapeutics drugs that targets the invasion and metastasis through inhibiting TGF-β-induced EMT in lung cancer.
Project description:Inactivation of TGF-beta family signaling is implicated in colorectal tumor progression. Using the cis-Apc/Smad4 mutant mice, a model of invasive colorectal cancer whose TGF-beta family signaling is blocked, we demonstrate here that a novel type of immature myeloid cells (iMCs) is recruited from the bone marrow to the tumor invasion front. These CD34+ iMCs express MMP9/2 and CC-chemokine receptor 1 (CCR1), and migrate toward its ligand CCL9. In the adenocarcinomas, expression of CCL9 is increased in the tumor epithelium. Such changes in the chemokine expression or the CD34+ iMC recruitment are not observed in the Apc (+/–) mice, a model of adenomatous polyposis. By knocking out Ccr1 gene in the cis-Apc/Smad4 mutant mice, we further demonstrate that lack of CCR1 prevents the accumulation of CD34+ iMCs at the invasion front and suppresses tumor invasion. These results indicate that loss of the TGF-beta family signaling in tumor epithelium causes accumulation of iMCs that help tumor invasion. Keywords: disease state analysis
Project description:Transformed human esophageal keratinocyte cell line EPC2-T (EPC2-hTERT-EGFR-cyclin D1-p53R175H) cells were stimulated with or without 2.5 ng/ml recombinant human TGF-beta1 for 10 days. The above cells were subjected to treatment for 10 days with or without 0.5 µg/ml doxycycline (DOX) to activate tetracycline-inducible (tet-on) ICN1, an active form of Notch1.
Project description:Vascular endothelial (VE-)cadherin is a homotypic adhesion protein that is expressed selectively by ECs in which it enables formation of tight vessels and regulation of vascular permeability. Since VE-cadherin is also strongly expressed in placental trophoblasts, it is a prime candidate for a molecular mechanism of vascular mimicry by those cells. Here, we show that the VE-cadherin is required for trophoblast migration and endovascular invasion into the maternal decidua. VE-cadherin deficiency results in loss of spiral artery remodeling due to a lack of invasive trophoblasts, leading to decreased flow of maternal blood into the placenta, fetal growth retardation and death. Loss of trophoblast invasion prevents decidualization, extracellular matrix remodeling, and immune cell clearance. These studies identify VE-cadherin as essential for trophoblast migration and coordination of decidual changes during endovascular invasion. They further suggest endothelial proteins such as VE-cadherin that are expressed by trophoblasts may play functionally distinct roles that do not simply mimic those in ECs.
Project description:Transforming growth factor- (TGF-) signaling is a critical driver of epithelial–mesenchymal transition (EMT) and cancer progression. However, the regulatory roles of long non-coding RNAs (lncRNAs) in TGF--induced EMT and cancer progression are not well understood. Here, we identified an unannotated nuclear lncRNA LETS1 (LncRNA Enforcing TGF- Signaling 1) as a novel TGF-/SMAD target gene. Loss of LETS1 attenuates TGF--induced EMT, migration and extravasation in breast and lung cancer cells. LETS1 potentiates TGF-/SMAD signaling by stabilizing cell surface TGF- type I receptor (TRI) and thereby forms a positive feedback loop. Mechanistically, LETS1 inhibits TRI polyubiquitination by inducing the orphan nuclear receptor 4A1 (NR4A1) expression, a critical determinant of a destruction complex for inhibitory SMAD7. An unbiased interactome analysis identified the Nuclear Factor of Activated T Cells (NFAT5) as a protein partner of LETS1 to mediate activation of NR4A1 promoter. Overall, our findings characterize LETS1 as an EMT-promoting lncRNA and elucidate the mechanism by which nuclear LETS1 potentiates TGF- receptor signaling.
Project description:To evaluate geneexpression profile in developing joints vs adjacent growth plate in control and TGF-beta type II receptor conditional knock-out in limb mesenchyjme