scholarly journals Inflammation, but not infection, induces EMT in human amnion epithelial cells

Reproduction ◽  
2020 ◽  
Vol 160 (4) ◽  
pp. 627-638
Author(s):  
Mariana de Castro Silva ◽  
Lauren S Richardson ◽  
Talar Kechichian ◽  
Rheanna Urrabaz-Garza ◽  
Márcia Guimarães da Silva ◽  
...  

A non-reversible state of epithelial to mesenchymal transition (EMT) at term accumulates proinflammatory mesenchymal cells and predisposes fetal membrane to weakening prior to delivery at term. We investigated the induction of EMT in amnion epithelial cells (AEC) in response to inflammation and infection associated with spontaneous preterm birth (SPTB). For this, membranes from SPTB were screened for EMT markers. Primary AEC in culture were treated with TNF-α (10 and 50 ng/mL) and LPS (50 and 100 ng/mL) for 72 h. Cell shape index (SI) was determined based on morphological shift (microscopy followed by ImageJ software analysis). Immunocytochemistry and Western blot assessed changes in epithelial markers (cytokeratin-18 and E-cadherin) and mesenchymal markers (vimentin and N-cadherin). Involvement of transforming growth factor beta (TGF-β) in EMT induction and EMT associated inflammation was tested using specific markers (Western blot) and by measuring MMP9 (ELISA), respectively. We report that PTB is associated with fetal membrane EMT. TNF-α produced dose- and time-dependent induction of EMT; within 24 h by 50 ng/mL and after 72 h by 10 ng/mL. AEC showed mesenchymal morphology, lower E-cadherin, higher vimentin and N-cadherin and higher MMP9 compared to control. TNF-α-induced EMT was not associated with canonical TGF-β pathway. LPS, regardless of dose or time, did not induce EMT in AEC. We conclude that PTB with intact membranes is associated with EMT. Our data suggest that inflammation, but not infection, is associated with non-canonical activation of EMT and inflammation that can predispose membrane to undergo weakening.

2018 ◽  
Vol 16 (1) ◽  
pp. 571-582 ◽  
Author(s):  
Xiaosong Shan ◽  
Qian Liu ◽  
Zhenye Li ◽  
Chuzhong Li ◽  
Hua Gao ◽  
...  

AbstractBackgroundThe detection and treatment of invasive growth hormone-secreting pituitary adenoma (GHPA) remains challenging. Several transcription factors promoting the epithelial–mesenchymal transition (EMT) can act as cofactors for the transforming growth factor-beta (TGF-ß)/SMAD4. The goal of this study was to investigate the association of SMAD4 expression and clinicopathologic features using a tissue microarray analysis (TMA). The levels of SMAD4 and the related genes of EMT in GHPAs were analyzed by q-PCR and western blot. SMAD4 was strongly expressed in 15/19 cases (78.9%) of invasive GHPA and 10/42 cases (23.8%) of noninvasive GHPA (χ2=10.887,p=0.000). In the high SMAD4 group, a headache was reported in 16/25 cases (64%) compared with 13/36 cases (36.1%) in the low SMAD4 group (χ2=4.565,p=0.032). The progression-free survival (PFS) in the high group was lower than that in the low group (p=0.026). qRT-PCR and western blot analysis further revealed a significant downregulation of E-cadherin and upregulation of N-cadherin and vimentin in the invasive GHPA group. SMAD4 was associated with increased levels of invasion of GH3 cells, as determined by a transwell test. SMAD4 downregulated E-cadherin levels and increased the levels of N-cadherin and vimentin. Our data provide evidence that SMAD4 is a potential prognosis biomarker and a therapeutic target for patients with invasive GHPA.


2009 ◽  
Vol 20 (22) ◽  
pp. 4751-4765 ◽  
Author(s):  
Ewa Kolosionek ◽  
Rajkumar Savai ◽  
Hossein Ardeschir Ghofrani ◽  
Norbert Weissmann ◽  
Andreas Guenther ◽  
...  

Epithelial–mesenchymal transition (EMT) has emerged as a critical event in the pathogenesis of organ fibrosis and cancer and is typically induced by the multifunctional cytokine transforming growth factor (TGF)-β1. The present study was undertaken to evaluate the potential role of phosphodiesterases (PDEs) in TGF-β1-induced EMT in the human alveolar epithelial type II cell line A549. Stimulation of A549 with TGF-β1 induced EMT by morphological alterations and by expression changes of the epithelial phenotype markers E-cadherin, cytokeratin-18, zona occludens-1, and the mesenchymal phenotype markers, collagen I, fibronectin, and α-smooth muscle actin. Interestingly, TGF-β1 stimulation caused twofold increase in total cAMP-PDE activity, contributed mostly by PDE4. Furthermore, mRNA and protein expression demonstrated up-regulation of PDE4A and PDE4D isoforms in TGF-β1-stimulated cells. Most importantly, treatment of TGF-β1 stimulated epithelial cells with the PDE4-selective inhibitor rolipram or PDE4 small interfering RNA potently inhibited EMT changes in a Smad-independent manner by decreasing reactive oxygen species, p38, and extracellular signal-regulated kinase phosphorylation. In contrast, the ectopic overexpression of PDE4A and/or PDE4D resulted in a significant loss of epithelial marker E-cadherin but did not result in changes of mesenchymal markers. In addition, Rho kinase signaling activated by TGF-β1 during EMT demonstrated to be a positive regulator of PDE4. Collectively, the findings presented herein suggest that TGF-β1 mediated up-regulation of PDE4 promotes EMT in alveolar epithelial cells. Thus, targeting PDE4 isoforms may be a novel approach to attenuate EMT-associated lung diseases such as pulmonary fibrosis and lung cancer.


2018 ◽  
Vol 315 (3) ◽  
pp. H658-H668 ◽  
Author(s):  
Danah S. Al-Hattab ◽  
Hamza A. Safi ◽  
Raghu S. Nagalingam ◽  
Rushita A. Bagchi ◽  
Matthew T. Stecy ◽  
...  

Numerous physiological and pathological events, from organ development to cancer and fibrosis, are characterized by an epithelial-to-mesenchymal transition (EMT), whereby adherent epithelial cells convert to migratory mesenchymal cells. During cardiac development, proepicardial organ epithelial cells undergo EMT to generate fibroblasts. Subsequent stress or damage induces further phenotype conversion of fibroblasts to myofibroblasts, causing fibrosis via synthesis of an excessive extracellular matrix. We have previously shown that the transcription factor scleraxis is both sufficient and necessary for the conversion of cardiac fibroblasts to myofibroblasts and found that scleraxis knockout reduced cardiac fibroblast numbers by 50%, possibly via EMT attenuation. Scleraxis induced expression of the EMT transcriptional regulators Twist1 and Snai1 via an unknown mechanism. Here, we report that scleraxis binds to E-box consensus sequences within the Twist1 and Snai1 promoters to transactivate these genes directly. Scleraxis upregulates expression of both genes in A549 epithelial cells and in cardiac myofibroblasts. Transforming growth factor-β induces EMT, fibrosis, and scleraxis expression, and we found that transforming growth factor-β-mediated upregulation of Twist1 and Snai1 completely depends on the presence of scleraxis. Snai1 knockdown upregulated the epithelial marker E-cadherin; however, this effect was lost after scleraxis overexpression, suggesting that scleraxis may repress E-cadherin expression. Together, these results indicate that scleraxis can regulate EMT via direct transactivation of the Twist1 and Snai1 genes. Given the role of scleraxis in also driving the myofibroblast phenotype, scleraxis appears to be a critical controller of fibroblast genesis and fate in the myocardium and thus may play key roles in wound healing and fibrosis. NEW & NOTEWORTHY The molecular mechanism by which the transcription factor scleraxis mediates Twist1 and Snai1 gene expression was determined. These results reveal a novel means of transcriptional regulation of epithelial-to-mesenchymal transition and demonstrate that transforming growth factor-β-mediated epithelial-to-mesenchymal transition is dependent on scleraxis, providing a potential target for controlling this process.


2018 ◽  
Vol 475 (8) ◽  
pp. 1427-1440 ◽  
Author(s):  
Mi-Hyun Nam ◽  
Ram H. Nagaraj

Advanced glycation end products (AGEs) are post-translational modifications formed from the reaction of reactive carbonyl compounds with amino groups in proteins. Our laboratory has previously shown that AGEs in extracellular matrix (ECM) proteins promote TGFβ2 (transforming growth factor-beta 2)-mediated epithelial-to-mesenchymal transition (EMT) of lens epithelial cells (LECs), which could play a role in fibrosis associated with posterior capsule opacification. We have also shown that αB-crystallin plays an important role in TGFβ2-mediated EMT of LECs. Here, we investigated the signaling mechanisms by which ECM-AGEs enhance TGFβ2-mediated EMT in LECs. We found that in LECs cultured on AGE-modified basement protein extract (AGE-BME), TGFβ2 treatment up-regulated the mesenchymal markers α-SMA (α-smooth muscle actin) and αB-crystallin and down-regulated the epithelial marker E-cadherin more than LECs cultured on unmodified BME and treated with TGFβ2. Using a Multiplex Assay, we found that AGE-BME significantly up-regulated the noncanonical pathway by promoting phosphorylation of ERK (extracellular signal-regulated kinases), AKT, and p38 MAPK (mitogen-activated protein kinases) during TGFβ2-mediated EMT. This EMT response was strongly suppressed by inhibition of AKT and p38 MAPK phosphorylation. The AKT inhibitor LY294002 also suppressed TGFβ2-induced up-regulation of nuclear Snail and reduced phosphorylation of GSK3β. Inhibition of Snail expression suppressed TGFβ2-mediated α-SMA expression. αB-Crystallin was up-regulated in an AKT-dependent manner during AGE-BME/TGFβ2-mediated EMT in LECs. The absence of αB-crystallin in LECs suppressed TGFβ2-induced GSK3β phosphorylation, resulting in lower Snail levels. Taken together, these results show that ECM-AGEs enhance the TGFβ2-mediated EMT response through activation of the AKT/Snail pathway, in which αB-crystallin plays an important role as a linker between the TGFβ2 and AGE-mediated signaling pathways.


2008 ◽  
Vol 294 (5) ◽  
pp. F1238-F1248 ◽  
Author(s):  
Larissa Ivanova ◽  
Michael J. Butt ◽  
Douglas G. Matsell

Progressive organ damage due to tissue scarring and fibrosis is a paradigm shared by numerous human diseases including chronic kidney disease. The purpose of this study was to confirm the hypothesis that collecting duct (CD) epithelial cells can undergo mesenchymal transition (EMT) in vitro. The mechanism by which CDs undergo EMT is complex and involves both early and late cellular events. Early events include rapid insulin-like growth factor (IGF)-induced Akt and GSK-3β phosphorylation, associated with early disruption of E-cadherin-β-catenin membrane colocalization, with translocation of E-cadherin to endosomes, with translocation of β-catenin to the nucleus, and with an increase in Snail expression. Transforming growth factor-β1, on the other hand, induced early activation of Smad3 and its translocation to the nucleus, Erk1/2 phosphorylation, and early disruption of membrane E-cadherin localization. The late consequences of these events included a phenotypic transformation of the cells to a mesenchymal morphology with associated increase in vimentin and α-smooth muscle actin protein expression and a decrease in total cellular E-cadherin expression, detectable as early as 24 h after stimulation.


Cells ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 1287 ◽  
Author(s):  
Lejun Zhang ◽  
Yang Ye ◽  
Rana Dhar ◽  
Jinsong Deng ◽  
Huifang Tang

The xCELLigence real-time cell analysis (RTCA) system has the potential to detect cellular proliferation, migration, cytotoxicity, adherence, and remodeling. Although the RTCA system is widely recognized as a noninvasive and efficient tool for real-time monitoring of cellular fate, it cannot describe detailed cell morphological parameters, such as length and intensity. Transforming growth factor beta(TGF-β) induced the epithelial–mesenchymal transition (EMT), which produces significant changes in cellular morphology, so we used TGF-β to treat A549 epithelial cells in this study. We compared it with lipopolysaccharide (LPS) and cigarette smoke extract (CSE) as stimulators. We developed an efficient algorithm to quantify the morphological cell changes. This algorithm is comprised of three major parts: image preprocessing, Hough transform (HT), and post-processing. We used the RTCA system to record the A549 cell index. Western blot was used to confirm the EMT. The RTCA system showed that different stimulators produce different cell index curves. The algorithm determined the lengths of the detected lines of cells, and the results were similar to the RTCA system in the TGF-β group. The Western blot results show that TGF-β changed the EMT markers, but the other stimulator remained unchanged. Optics-based computer vision techniques can supply the requisite information for the RTCA system based on good correspondence between the results.


2006 ◽  
Vol 17 (4) ◽  
pp. 1871-1879 ◽  
Author(s):  
Damian Medici ◽  
Elizabeth D. Hay ◽  
Daniel A. Goodenough

Transforming growth factor beta 1 (TGF-β1) has been shown to induce epithelial-mesenchymal transition (EMT) during various stages of embryogenesis and progressive disease. This alteration in cellular morphology is typically characterized by changes in cell polarity and loss of adhesion proteins such as E-cadherin. Here we demonstrate that EMT is associated with loss of claudin-1, claudin-2, occludin, and E-cadherin expression within 72 h of exposure to TGF-β1 in MDCKII cells. It has been suggested that this expression loss occurs through TGF-β1 in a Smad-independent mechanism, involving MEK and PI3K pathways, which have previously been shown to induce expression of the Snail (SNAI-1) gene. Here we show that these pathways are responsible for loss of tight junctions and a partial loss of E-cadherin. However, our results also demonstrate that a complete loss of E-cadherin and transformation to the mesenchymal phenotype are dependent on Smad signaling, which subsequently stimulates formation of β-catenin/LEF-1 complexes that induce EMT.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Demin Cheng ◽  
Qi Xu ◽  
Yue Wang ◽  
Guanru Li ◽  
Wenqing Sun ◽  
...  

Abstract Background Silicosis is one of the most common occupational pulmonary fibrosis caused by respirable silica-based particle exposure, with no ideal drugs at present. Metformin, a commonly used biguanide antidiabetic agent, could activate AMP-activated protein kinase (AMPK) to exert its pharmacological action. Therefore, we sought to investigate the role of metformin in silica-induced lung fibrosis. Methods The anti-fibrotic role of metformin was assessed in 50 mg/kg silica-induced lung fibrosis model. Silicon dioxide (SiO2)-stimulated lung epithelial cells/macrophages and transforming growth factor-beta 1 (TGF-β1)-induced differentiated lung fibroblasts were used for in vitro models. Results At the concentration of 300 mg/kg in the mouse model, metformin significantly reduced lung inflammation and fibrosis in SiO2-instilled mice at the early and late fibrotic stages. Besides, metformin (range 2–10 mM) reversed SiO2-induced cell toxicity, oxidative stress, and epithelial-mesenchymal transition process in epithelial cells (A549 and HBE), inhibited inflammation response in macrophages (THP-1), and alleviated TGF-β1-stimulated fibroblast activation in lung fibroblasts (MRC-5) via an AMPK-dependent pathway. Conclusions In this study, we identified that metformin might be a potential drug for silicosis treatment.


Cancers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1976 ◽  
Author(s):  
Antje M. Richter ◽  
Miriam M. Küster ◽  
Michelle L. Woods ◽  
Sara K. Walesch ◽  
Mira Y. Gökyildirim ◽  
...  

The Ras Association Domain Family (RASSF) encodes members of tumor suppressor genes which are frequently inactivated in human cancers. Here, the function and the regulation of RASSF10, that contains a RA (Ras-association) and two coiled domains, was investigated. We utilized mass spectrometry and immuno-precipitation to identify interaction partners of RASSF10. Additionally, we analyzed the up- and downstream pathways of RASSF10 that are involved in its tumor suppressive function. We report that RASSF10 binds ASPP1 (Apoptosis-stimulating protein of p53) and ASPP2 through its coiled-coils. Induction of RASSF10 leads to increased protein levels of ASPP2 and acts negatively on cell cycle progression. Interestingly, we found that RASSF10 is a target of the EMT (epithelial mesenchymal transition) driver TGFβ (Transforming growth factor beta) and that negatively associated genes of RASSF10 are significantly over-represented in an EMT gene set collection. We observed a positive correlation of RASSF10 expression and E-cadherin that prevents EMT. Depletion of RASSF10 by CRISPR/Cas9 technology induces the ability of lung cancer cells to proliferate and to invade an extracellular matrix after TGFβ treatment. Additionally, knockdown of RASSF10 or ASPP2 induced constitutive phosphorylation of SMAD2 (Smad family member 2). Moreover, we found that epigenetic reduction of RASSF10 levels correlates with tumor progression and poor survival in human cancers. Our study indicates that RASSF10 acts a TGFβ target gene and negatively regulates cell growth and invasion through ASPP2. This data suggests that epigenetic loss of RASSF10 contributes to tumorigenesis by promoting EMT induced by TGFβ.


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