scholarly journals Endothelial ERK1/2 signaling maintains integrity of the quiescent endothelium

2019 ◽  
Vol 216 (8) ◽  
pp. 1874-1890 ◽  
Author(s):  
Nicolas Ricard ◽  
Rizaldy P. Scott ◽  
Carmen J. Booth ◽  
Heino Velazquez ◽  
Nicholas A. Cilfone ◽  
...  

To define the role of ERK1/2 signaling in the quiescent endothelium, we induced endothelial Erk2 knockout in adult Erk1−/− mice. This resulted in a rapid onset of hypertension, a decrease in eNOS expression, and an increase in endothelin-1 plasma levels, with all mice dying within 5 wk. Immunostaining and endothelial fate mapping showed a robust increase in TGFβ signaling leading to widespread endothelial-to-mesenchymal transition (EndMT). Fibrosis affecting the cardiac conduction system was responsible for the universal lethality in these mice. Other findings included renal endotheliosis, loss of fenestrated endothelia in endocrine organs, and hemorrhages. An ensemble computational intelligence strategy, comprising deep learning and probabilistic programing of RNA-seq data, causally linked the loss of ERK1/2 in HUVECs in vitro to activation of TGFβ signaling, EndMT, suppression of eNOS, and induction of endothelin-1 expression. All in silico predictions were verified in vitro and in vivo. In summary, these data establish the key role played by ERK1/2 signaling in the maintenance of vascular normalcy.

Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Katrin Nather ◽  
Mónica Flores-Muñoz ◽  
Rhian M Touyz ◽  
Christopher M Loughrey ◽  
Stuart A Nicklin

Cardiac fibrosis accompanies numerous cardiovascular diseases (CVD) such as hypertension and myocardial infarction and increases myocardial stiffness leading to contractile dysfunction. Recently, endothelial-to-mesenchymal transition (EndMT) has been shown to contribute to myocardial fibrosis. EndMT describes a process by which endothelial cells transform into mesenchymal cells such as fibroblasts and has been implicated in many fibrotic diseases. Angiotensin II (AngII) plays a key role in myocardial fibrosis and has been associated with the activation of fibroblasts to myofibroblasts and an increase in myocardial collagen deposition. Here, we assessed the role of AngII in capillary loss and EndMT in vivo and in vitro . C57BL/6J mice were infused with H 2 O (control) or 24μg/kg/hr AngII for 4 weeks. Mice infused with AngII developed significant cardiac fibrosis characterised by the deposition of collagen I (2.5-fold vs. control; p<0.05) and III (1.9-fold vs. control; p<0.05). Capillary density was assessed by CD31 immunohistochemistry and revealed significant vascular rarefaction (control 2161±111 vs . AngII 838±132 capillaries/mm 2 ; p<0.05). To investigate whether AngII can induce EndMT in vitro , human coronary artery endothelial cells were stimulated with 10ng/mL TGFβ 1 alone or in combination with 1μM AngII for 10 days. AngII significantly enhanced TGFβ 1 -induced gene expression of α-smooth muscle actin (TGFβ 1 1.8-fold; TGFβ 1 ±AngII 4.3-fold vs . control; p<0.05) and collagen I (TGFβ 1 9.2-fold; TGFβ 1 +AngII 30.2-fold vs . control; p<0.05). Concomitantly, AngII significantly increased α-smooth muscle actin protein expression (TGFβ 1 3.9-fold; TGFβ 1 +AngII 23.6-fold vs . control; p<0.05) and significantly decreased CD31 expression (TGFβ 1 0.9-fold; TGFβ 1 +AngII 0.7-fold vs . control; p<0.05), suggesting AngII acts in concert with TGFβ 1 to enhance conversion of endothelial cells to myofibroblasts. Further studies investigating the underlying mechanism, including the role of the Smad pathway, are ongoing. These results demonstrate that AngII induces vascular rarefaction in vivo and potentiates TGFβ 1 -induced EndMT in vitro. Understanding the molecular basis for these observations may help to identify new therapeutic options in CVD.


2010 ◽  
Vol 21 (2) ◽  
pp. 244-253 ◽  
Author(s):  
Matthew Reid MacPherson ◽  
Patricia Molina ◽  
Serhiy Souchelnytskyi ◽  
Christer Wernstedt ◽  
Jorge Martin-Pérez ◽  
...  

Snail1 is a major factor for epithelial-mesenchymal transition (EMT), an important event in tumor metastasis and in other pathologies. Snail1 is tightly regulated at transcriptional and posttranscriptional levels. Control of Snail1 protein stability and nuclear export by GSK3β phosphorylation is important for Snail1 functionality. Stabilization mechanisms independent of GSK3β have also been reported, including interaction with LOXL2 or regulation of the COP9 signalosome by inflammatory signals. To get further insights into the role of Snail1 phosphorylation, we have performed an in-depth analysis of in vivo human Snail1 phosphorylation combined with mutational studies. We identify new phosphorylation sites at serines 11, 82, and 92 and confirmed previously suggested phosphorylations at serine 104 and 107. Serines 11 and 92 participate in the control of Snail1 stability and positively regulate Snail1 repressive function and its interaction with mSin3A corepressor. Furthermore, serines 11 and 92 are required for Snail1-mediated EMT and cell viability, respectively. PKA and CK2 have been characterized as the main kinases responsible for in vitro Snail1 phosphorylation at serine 11 and 92, respectively. These results highlight serines 11 and 92 as new players in Snail1 regulation and suggest the participation of CK2 and PKA in the modulation of Snail1 functionality.


2019 ◽  
Vol 39 (10) ◽  
pp. 2168-2191 ◽  
Author(s):  
Bronson A. Haynes ◽  
Li Fang Yang ◽  
Ryan W. Huyck ◽  
Eric J. Lehrer ◽  
Joshua M. Turner ◽  
...  

Objective: Endothelial cells (EC) in obese adipose tissue (AT) are exposed to a chronic proinflammatory environment that may induce a mesenchymal-like phenotype and altered function. The objective of this study was to establish whether endothelial-to-mesenchymal transition (EndoMT) is present in human AT in obesity and to investigate the effect of such transition on endothelial function and the endothelial particulate secretome represented by extracellular vesicles (EV). Approach and Results: We identified EndoMT in obese human AT depots by immunohistochemical co-localization of CD31 or vWF and α-SMA (alpha-smooth muscle actin). We showed that AT EC exposed in vitro to TGF-β (tumor growth factor-β), TNF-α (tumor necrosis factor-α), and IFN-γ (interferon-γ) undergo EndoMT with progressive loss of endothelial markers. The phenotypic change results in failure to maintain a tight barrier in culture, increased migration, and reduced angiogenesis. EndoMT also reduced mitochondrial oxidative phosphorylation and glycolytic capacity of EC. EVs produced by EC that underwent EndoMT dramatically reduced angiogenic capacity of the recipient naïve ECs without affecting their migration or proliferation. Proteomic analysis of EV produced by EC in the proinflammatory conditions showed presence of several pro-inflammatory and immune proteins along with an enrichment in angiogenic receptors. Conclusions: We demonstrated the presence of EndoMT in human AT in obesity. EndoMT in vitro resulted in production of EV that transferred some of the functional and metabolic features to recipient naïve EC. This result suggests that functional and molecular features of EC that underwent EndoMT in vivo can be disseminated in a paracrine or endocrine fashion and may induce endothelial dysfunction in distant vascular beds.


2021 ◽  
Vol 11 ◽  
Author(s):  
Suzhen Wang ◽  
Tianning Yang ◽  
Zhengxiang He

BackgroundThe involvement of microRNA-338-5p in modulating NPC pathogenesis is still largely unknown, and this study aimed to investigate this issue.MethodsThe expressions of cancer associated genes were determined by Real-Time qPCR and Western Blot, and cell apoptosis was determined by flow cytometer (FCM). CCK-8 assay and colony formation assay were respectively used to determine cell proliferation and colony formation abilities. Transwell assay was used to evaluate cell migration. The expression levels of Ki67 protein in mice tissues were measured by Immunohistochemistry (IHC) assay.ResultsThe present study found that microRNA-338-5p suppressed NPC progression by degrading its downstream target, Wnt family member 2B (WNT2B). Specifically, microRNA-338-5p tended to be low-expressed in NPC tissues and cell lines, compared to the non-tumor nasopharyngeal mucosa tissues and normal nasopharyngeal cell line (NP69). Upregulation of microRNA-338-5p inhibited proliferation, mobility, and epithelial-mesenchymal transition (EMT) in NPC cells in vitro, while silencing of microRNA-338-5p had opposite effects. Consistently, microRNA-338-5p suppressed tumorigenesis of NPC cells in vivo. In addition, microRNA-338-5p targeted WNT2B for degradation and inhibition, and the inhibiting effects of microRNA-338-5p overexpression on NPC development were reversed by upregulating WNT2B.ConclusionsTaken together, we concluded that microRNA-338-5p targeted WNT2B to hinder NPC development.


Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Seock-Won Youn ◽  
Sudhahar Varadarajan ◽  
Archita Das ◽  
Ronald D McKinney ◽  
Tohru Fukai ◽  
...  

Background: Endothelial to mesenchymal transition (EndMT) is induced by inflammation and contributes to fibrosis; however, underlying mechanism is poorly understood. Cu plays an important role in physiological processes and pathophysiologies associated with inflammatory diseases. Since excess Cu is toxic, bioavailability of Cu is tightly controlled by Cu exporter ATP7A, which obtains Cu via Cu chaperone, Atox1, and exclude Cu. We reported that Atox1 also functions as a Cu dependent transcription factor. However, role of Cu transport proteins in EndMT is entirely unknown.[[Unable to Display Character: &#8232;]] Results: Here we show that TNFα stimulation for 24hr in HUVEC significantly decreased ATP7A protein (80%) and increased intracellular Cu and Atox1 in nucleus, which was associated with shape change forming EndMT. ATP7A depletion with shRNA in EC significantly reduced EC markers (VE-cadherin and VEGFR2) and increased mesenchymal markers (αSMA, Calponin, SM22α, Collagen I/II). ATP7A siRNA also increased intracellular Cu and nuclear Atox1. These ATP7A knockdown-induced phenotype changes were inhibited by Cu chelators BCS and TTM. Mechanistically, microarray and qPCR based screening revealed that ATP7A knockdown in EC significantly increased miR21 (2.5 fold) and miR125b (1.5 fold) which induce EndMT in a Cu-dependent manner. Of note, promoters of both miR21 and miR125b have Cu dependent transcription factor Atox1 binding sites. Consistent with this, overexpression of Atox1 increased miR21 and miR125b expression as well as promoted EndMT. In vivo, ATP7A mutant (ATP7Amut) mice with reduced Cu export function showed impaired blood flow recovery and reduced arteriogenesis while increased αSMA+ cells and fibrosis in capillary network after ischemic injury. Moreover, ATP7Amut mice crossed with ApoE-/- mice with high fat diet (HFD) induced robust fibrosis and enhanced atherosclerotic lesion vs ApoE-/-/HFD mice.[[Unable to Display Character: &#8232;]] Conclusions: ATP7A protects against fibrosis by preventing EndMT via nuclear Atox1-mediated upregulation of miR21 and miR125b which induce EndMT, in Cu dependent manner. These findings provide the foundation for novel protective role of Cu transport proteins against EndMT- and fibrosis-mediated cardiovascular diseases.


2020 ◽  
Vol 11 (12) ◽  
Author(s):  
Hongli Li ◽  
Qingjie Mu ◽  
Guoxin Zhang ◽  
Zhixin Shen ◽  
Yuanyuan Zhang ◽  
...  

AbstractIncreasing lines of evidence indicate the role of long non-coding RNAs (LncRNAs) in gene regulation and tumor development. Hence, it is important to elucidate the mechanisms of LncRNAs underlying the proliferation, metastasis, and invasion of lung adenocarcinoma (LUAD). We employed microarrays to screen LncRNAs in LUAD tissues with and without lymph node metastasis and revealed their effects on LUAD. Among them, Linc00426 was selected for further exploration in its expression, the biological significance, and the underlying molecular mechanisms. Linc00426 exhibits ectopic expression in LUAD tissues and cells. The ectopic expression has been clinically linked to tumor size, lymphatic metastasis, and tumor differentiation of patients with LUAD. The deregulation of Linc00426 contributes to a notable impairment in proliferation, invasion, metastasis, and epithelial–mesenchymal transition (EMT) in vitro and in vivo. Mechanistically, the deregulation of Linc00426 could reduce cytoskeleton rearrangement and matrix metalloproteinase expression. Meanwhile, decreasing the level of Linc00426 or increasing miR-455-5p could down-regulate the level of UBE2V1. Thus, Linc00426 may act as a competing endogenous RNA (ceRNA) to abate miR-455-5p-dependent UBE2V1 reduction. We conclude that Linc00426 accelerates LUAD progression by acting as a molecular sponge to regulate miR-455-5p, and may be a potential novel tumor marker for LUAD.


Biomolecules ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1676
Author(s):  
Monserrat Olea-Flores ◽  
Juan C. Juárez-Cruz ◽  
Miriam D. Zuñiga-Eulogio ◽  
Erika Acosta ◽  
Eduardo García-Rodríguez ◽  
...  

Leptin is a hormone secreted mainly by adipocytes; physiologically, it participates in the control of appetite and energy expenditure. However, it has also been linked to tumor progression in different epithelial cancers. In this review, we describe the effect of leptin on epithelial–mesenchymal transition (EMT) markers in different study models, including in vitro, in vivo, and patient studies and in various types of cancer, including breast, prostate, lung, and ovarian cancer. The different studies report that leptin promotes the expression of mesenchymal markers and a decrease in epithelial markers, in addition to promoting EMT-related processes such as cell migration and invasion and poor prognosis in patients with cancer. Finally, we report that leptin has the greatest biological relevance in EMT and tumor progression in breast, lung, prostate, esophageal, and ovarian cancer. This relationship could be due to the key role played by the enriched tumor microenvironment in adipose tissue. Together, these findings demonstrate that leptin is a key biomolecule that drives EMT and metastasis in cancer.


Cancers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1918
Author(s):  
Yanyuan Wu ◽  
Marianna Sarkissyan ◽  
Ochanya Ogah ◽  
Juri Kim ◽  
Jaydutt V. Vadgama

Background: Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is associated with cancer progression. Our study examined the role of MALAT1 in breast cancer and the mechanisms involved in the regulation of MALAT1. Methods: In vitro cell and in vivo animal models were used to examine the role of MALAT1 in breast cancer. The interaction of FOXO1 (Forkhead Box O1) at the promoter region of MALAT1 was investigated by chromatin immunoprecipitation (ChIP) assay. Results: The data shows an elevated expression of MALAT1 in breast cancer tissues and cells compared to non-cancer tissues and cells. The highest level of MALAT1 was observed in metastatic triple-negative breast cancer and trastuzumab-resistant HER2 (human epidermal growth factor receptor 2) overexpressing (HER2+) cells. Knockdown of MALAT1 in trastuzumab-resistant HER2+ cells reversed epithelial to mesenchymal transition-like phenotype and cell invasiveness. It improved the sensitivity of the cell’s response to trastuzumab. Furthermore, activation of Akt by phosphorylation was associated with the upregulation of MALAT1. The transcription factor FOXO1 regulates the expression of MALAT1 via the PI3/Akt pathway. Conclusions: We show that MALAT1 contributes to HER2+ cell resistance to trastuzumab. Targeting the PI3/Akt pathway and stabilizing FOXO1 translocation could inhibit the upregulation of MALAT1.


2015 ◽  
Vol 112 (27) ◽  
pp. 8421-8426 ◽  
Author(s):  
Luca Bravi ◽  
Noemi Rudini ◽  
Roberto Cuttano ◽  
Costanza Giampietro ◽  
Luigi Maddaluno ◽  
...  

Cerebral cavernous malformation (CCM) is a disease of the central nervous system causing hemorrhage-prone multiple lumen vascular malformations and very severe neurological consequences. At present, the only recommended treatment of CCM is surgical. Because surgery is often not applicable, pharmacological treatment would be highly desirable. We describe here a murine model of the disease that develops after endothelial-cell–selective ablation of the CCM3 gene. We report an early, cell-autonomous, Wnt-receptor–independent stimulation of β-catenin transcription activity in CCM3-deficient endothelial cells both in vitro and in vivo and a triggering of a β-catenin–driven transcription program that leads to endothelial-to-mesenchymal transition. TGF-β/BMP signaling is then required for the progression of the disease. We also found that the anti-inflammatory drugs sulindac sulfide and sulindac sulfone, which attenuate β-catenin transcription activity, reduce vascular malformations in endothelial CCM3-deficient mice. This study opens previously unidentified perspectives for an effective pharmacological therapy of intracranial vascular cavernomas.


2018 ◽  
Vol 18 (6) ◽  
pp. 558-566 ◽  
Author(s):  
Jie Wu ◽  
Dingxin Di ◽  
Chen Zhao ◽  
Yingyi Liu ◽  
Hongxia Chen ◽  
...  

Glioma-associated oncogenes (GLIs) are zinc finger protein family members and downstream regulatory factors of the classic Hedgehog (Hh) signaling pathway. GLI proteins influence the growth and development of organisms and aid in tissue repair. However, aberrant expression of the GLI family member GLI1 promotes carcinogenesis by inducing epithelial–mesenchymal transition (EMT), angiogenesis, and other signaling pathways. Overexpression of GLI1 is thought to be an indicator of poor prognosis as well as a potential therapeutic target for cancers. GLI inhibitors such as zerumbone, GANT61, resveratrol, and cyclopamine depress the Hh pathway in vitro and in vivo cancer research, and other non-canonical pathways may also activate expression of GLI1. Here, we summarize GLI function in carcinogenesis and cancer-targeted therapy.


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