Podoplanin interaction with caveolin-1 promotes tumour cell migration and invasion

Migration And Invasion ◽

Dependent Manner ◽

Caveolin 1 ◽

Alveolar Epithelial ◽

Podoplanin Expression

AbstractPodoplanin, a highly O-glycosylated type-1 transmembrane glycoprotein, found in lymphatic endothelial cells, podocytes, alveolar epithelial cells and lymph node fibroblasts is also expressed by tumour cells, and is correlated with more aggressive disease. Despite numerous studies documenting podoplanin expression, the mechanisms underlying its tumour-promoting functions remain unclear. Using a murine melanoma cell line that endogenously expresses podoplanin, we demonstrate interactions with proteins necessary for cytoskeleton reorganization, adhesion and matrix degradation, and endocytosis/receptor recycling but also identify a novel interaction with caveolin-1. We generated a panel of podoplanin and caveolin-1 variants to determine the molecular interactions and functional consequences of these interactions. Complementary in vitro and in vivo systems confirmed the existence of a functional cooperation in which surface expression of both full length, signalling competent podoplanin and caveolin-1 are necessary to induce directional migration and invasion, which is executed via PAK1 and ERK1 pathways. Our findings establish that podoplanin signalling mediates the invasive properties of melanoma cells in a caveolin-1 dependent manner.Summary StatementThis manuscript describes a new interaction and functional cooperation between podoplanin and caveolin1 that drives tumour cell invasion into surrounding tissues.

Cross-talk between LAM cells and fibroblasts may influence alveolar epithelial cell behavior in Lymphangioleiomyomatosis

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00351.2021 ◽

2021 ◽

Author(s):

Debbie Clements ◽

Suzanne Miller ◽

Roya Babaei-Jadidi ◽

Mike Adam ◽

S. Steven Potter ◽

...

Keyword(s):

Epithelial Cells ◽

Cross Talk ◽

Ex Vivo ◽

Dependent Manner ◽

Epithelial Migration ◽

Alveolar Epithelial

Lymphangioleiomyomatosis (LAM) is a female specific cystic lung disease in which TSC2 deficient LAM cells, LAM-Associated Fibroblasts (LAFs) and other cell types infiltrate the lungs. LAM lesions can be associated with type II alveolar epithelial cells (AT2 cells). We hypothesised that the behaviour of AT2 cells in LAM is influenced locally by LAFs. We tested this hypothesis in patient samples and in vitro. In human LAM lung, nodular AT2 cells show enhanced proliferation when compared to parenchymal AT2 cells, demonstrated by increased Ki67 expression. Further, nodular AT2 cells express proteins associated with epithelial activation in other disease states including Matrix Metalloproteinase 7, and Fibroblast Growth Factor 7 (FGF7). In vitro, LAF conditioned medium is mitogenic and positively chemotactic for epithelial cells, increases the rate of epithelial repair and protects against apoptosis. In vitro, LAM patient-derived TSC2 null cells cocultured with LAFs upregulate LAF expression of the epithelial chemokine and mitogen FGF7, which is a potential mediator of fibroblast-epithelial crosstalk, in an mTOR dependent manner. In a novel in vitro model of LAM, ex vivo cultured LAM lung-derived microtissues promote both epithelial migration and adhesion. Our findings suggest that AT2 cells in LAM display a proliferative, activated phenotype and that fibroblast accumulation following LAM cell infiltration into the parenchyma contributes to this change in AT2 cell behaviour. Fibroblast-derived FGF7 may contribute to the cross-talk between LAFs and hyperplastic epithelium in vivo, but does not appear to be the main driver of the effects of LAFs on epithelial cells in vitro.

Influence of icariin on inflammation, apoptosis, invasion, and tumor immunity in cervical cancer by reducing the TLR4/MyD88/NF-κB and Wnt/β-catenin pathways

Cancer Cell International ◽

10.1186/s12935-021-01910-2 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Chunyang Li ◽

Shuangqing Yang ◽

Huaqing Ma ◽

Mengjia Ruan ◽

Luyan Fang ◽

...

Keyword(s):

Cervical Cancer ◽

Underlying Mechanism ◽

Tissue Growth ◽

Migration And Invasion ◽

Dependent Manner ◽

Antitumor Effects ◽

Siha Cells ◽

Cervical Cancer Cells

Abstract Background Cervical cancer is a type of the most common gynecology tumor in women of the whole world. Accumulating data have shown that icariin (ICA), a natural compound, has anti-cancer activity in different cancers, including cervical cancer. The study aimed to reveal the antitumor effects and the possible underlying mechanism of ICA in U14 tumor-bearing mice and SiHa cells. Methods The antitumor effects of ICA were investigated in vivo and in vitro. The expression of TLR4/MyD88/NF-κB and Wnt/β-catenin signaling pathways were evaluated. Results We found that ICA significantly suppressed tumor tissue growth and SiHa cells viability in a dose-dependent manner. Also, ICA enhanced the anti-tumor humoral immunity in vivo. Moreover, ICA significantly improved the composition of the microbiota in mice models. Additionally, the results clarified that ICA significantly inhibited the migration, invasion capacity, and expression levels of TGF-β1, TNF-α, IL-6, IL-17A, IL-10 in SiHa cells. Meanwhile, ICA was revealed to promote the apoptosis of cervical cancer cells by down-regulating Ki67, survivin, Bcl-2, c-Myc, and up-regulating P16, P53, Bax levels in vivo and in vitro. For the part of mechanism exploration, we showed that ICA inhibits the inflammation, proliferation, migration, and invasion, as well as promotes apoptosis and immunity in cervical cancer through impairment of TLR4/MyD88/NF-κB and Wnt/β-catenin pathways. Conclusions Taken together, ICA could be a potential supplementary agent for cervical cancer treatment.

TRIM72 is required for effective repair of alveolar epithelial cell wounding

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00172.2014 ◽

2014 ◽

Vol 307 (6) ◽

pp. L449-L459 ◽

Cited By ~ 15

Author(s):

Seong Chul Kim ◽

Thomas Kellett ◽

Shaohua Wang ◽

Miyuki Nishi ◽

Nagaraja Nagre ◽

...

Keyword(s):

Epithelial Cells ◽

Molecular Mechanisms ◽

Striated Muscle ◽

Lung Cells ◽

Alveolar Epithelial ◽

High Tidal Volume Ventilation

The molecular mechanisms for lung cell repair are largely unknown. Previous studies identified tripartite motif protein 72 (TRIM72) from striated muscle and linked its function to tissue repair. In this study, we characterized TRIM72 expression in lung tissues and investigated the role of TRIM72 in repair of alveolar epithelial cells. In vivo injury of lung cells was introduced by high tidal volume ventilation, and repair-defective cells were labeled with postinjury administration of propidium iodide. Primary alveolar epithelial cells were isolated and membrane wounding and repair were labeled separately. Our results show that absence of TRIM72 increases susceptibility to deformation-induced lung injury whereas TRIM72 overexpression is protective. In vitro cell wounding assay revealed that TRIM72 protects alveolar epithelial cells through promoting repair rather than increasing resistance to injury. The repair function of TRIM72 in lung cells is further linked to caveolin 1. These data suggest an essential role for TRIM72 in repair of alveolar epithelial cells under plasma membrane stress failure.

C3 Promotes Clearance of Klebsiella pneumoniae by A549 Epithelial Cells

Infection and Immunity ◽

10.1128/iai.72.3.1767-1774.2004 ◽

2004 ◽

Vol 72 (3) ◽

pp. 1767-1774 ◽

Cited By ~ 26

Author(s):

Beatriz de Astorza ◽

Guadalupe Cortés ◽

Catalina Crespí ◽

Carles Saus ◽

José María Rojo ◽

...

Keyword(s):

Epithelial Cells ◽

Klebsiella Pneumoniae ◽

Clinical Isolates ◽

Complement Components ◽

Innate Defense ◽

Alveolar Epithelial

ABSTRACT The airway epithelium represents a primary site for contact between microbes and their hosts. To assess the role of complement in this event, we studied the interaction between the A549 cell line derived from human alveolar epithelial cells and a major nosocomial pathogen, Klebsiella pneumoniae, in the presence of serum. In vitro, we found that C3 opsonization of poorly encapsulated K. pneumoniae clinical isolates and an unencapsulated mutant enhanced dramatically bacterial internalization by A549 epithelial cells compared to highly encapsulated clinical isolates. Local complement components (either present in the human bronchoalveolar lavage or produced by A549 epithelial cells) were sufficient to opsonize K. pneumoniae. CD46 could competitively inhibit the internalization of K. pneumoniae by the epithelial cells, suggesting that CD46 is a receptor for the binding of complement-opsonized K. pneumoniae to these cells. We observed that poorly encapsulated strains appeared into the alveolar epithelial cells in vivo but that (by contrast) they were completely avirulent in a mouse model of pneumonia compared to the highly encapsulated strains. Our results show that bacterial opsonization by complement enhances the internalization of the avirulent microorganisms by nonphagocytic cells such as A549 epithelial cells and allows an efficient innate defense.

Gene transfer of hepatocyte growth factor by electroporation reduces bleomycin-induced lung fibrosis

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00082.2006 ◽

2007 ◽

Vol 292 (2) ◽

pp. L529-L536 ◽

Cited By ~ 58

Author(s):

Amiq Gazdhar ◽

Patrick Fachinger ◽

Coretta van Leer ◽

Jaroslaw Pierog ◽

Mathias Gugger ◽

...

Keyword(s):

Growth Factor ◽

Gene Transfer ◽

Pulmonary Fibrosis ◽

Wound Repair ◽

Epithelial Repair ◽

Alveolar Epithelial ◽

Hepatocyte Growth

Abnormal alveolar wound repair contributes to the development of pulmonary fibrosis after lung injury. Hepatocyte growth factor (HGF) is a potent mitogenic factor for alveolar epithelial cells and may therefore improve alveolar epithelial repair in vitro and in vivo. We hypothesized that HGF could increase alveolar epithelial repair in vitro and improve pulmonary fibrosis in vivo. Alveolar wound repair in vitro was determined using an epithelial wound repair model with HGF-transfected A549 alveolar epithelial cells. Electroporation-mediated, nonviral gene transfer of HGF in vivo was performed 7 days after bleomycin-induced lung injury in the rat. Alveolar epithelial repair in vitro was increased after transfection of wounded epithelial monolayers with a plasmid encoding human HGF, pCikhHGF [human HGF (hHGF) gene expressed from the cytomegalovirus (CMV) immediate-early promoter and enhancer] compared with medium control. Electroporation-mediated in vivo HGF gene transfer using pCikhHGF 7 days after intratracheal bleomycin reduced pulmonary fibrosis as assessed by histology and hydroxyproline determination 14 days after bleomycin compared with controls treated with the same vector not containing the HGF sequence (pCik). Lung epithelial cell proliferation was increased and apoptosis reduced in hHGF-treated lungs compared with controls, suggesting increased alveolar epithelial repair in vivo. In addition, profibrotic transforming growth factor-β1 (TGF-β1) was decreased in hHGF-treated lungs, indicating an involvement of TGF-β1 in hHGF-induced reduction of lung fibrosis. In conclusion, electroporation-mediated gene transfer of hHGF decreases bleomycin-induced pulmonary fibrosis, possibly by increasing alveolar epithelial cell proliferation and reducing apoptosis, resulting in improved alveolar wound repair.

Flagellin/TLR5 Stimulate Myeloid Progenitors to Enter Lung Tissue and to Locally Differentiate Into Macrophages

Frontiers in Immunology ◽

10.3389/fimmu.2021.621665 ◽

2021 ◽

Vol 12 ◽

Author(s):

Xin Lei ◽

Jara Palomero ◽

Iris de Rink ◽

Tom de Wit ◽

Martijn van Baalen ◽

...

Keyword(s):

Epithelial Cells ◽

Low Frequency ◽

Lavage Fluid ◽

Lung Lavage ◽

Mouse Bone Marrow ◽

Alveolar Epithelial ◽

Toll Like Receptor 5

Toll-like receptor 5 (TLR5) is the receptor of bacterial Flagellin. Reportedly, TLR5 engagement helps to combat infections, especially at mucosal sites, by evoking responses from epithelial cells and immune cells. Here we report that TLR5 is expressed on a previously defined bipotent progenitor of macrophages (MΦs) and osteoclasts (OCs) that resides in the mouse bone marrow (BM) and circulates at low frequency in the blood. In vitro, Flagellin promoted the generation of MΦs, but not OCs from this progenitor. In vivo, MΦ/OC progenitors were recruited from the blood into the lung upon intranasal inoculation of Flagellin, where they rapidly differentiated into MΦs. Recruitment of the MΦ/OC progenitors into the lung was likely promoted by the CCL2/CCR2 axis, since the progenitors expressed CCR2 and type 2 alveolar epithelial cells (AECs) produced CCL2 upon stimulation by Flagellin. Moreover, CCR2 blockade reduced migration of the MΦ/OC progenitors toward lung lavage fluid (LLF) from Flagellin-inoculated mice. Our study points to a novel role of the Flagellin/TLR5 axis in recruiting circulating MΦ/OC progenitors into infected tissue and stimulating these progenitors to locally differentiate into MΦs. The progenitor pathway to produce MΦs may act, next to monocyte recruitment, to fortify host protection against bacterial infection at mucosal sites.

Curcumol inhibits malignant biological behaviors and TMZ-resistance of glioma cells via reducing long noncoding RNA FoxD2-As1 promoted EZH2 activation

10.21203/rs.3.rs-415245/v1 ◽

2021 ◽

Author(s):

Xuyang Lv ◽

Jiangchuan Sun ◽

Linfeng Hu ◽

Ying Qian ◽

Chunlei Fan ◽

...

Keyword(s):

Cell Proliferation ◽

Noncoding Rna ◽

Glioma Cell ◽

Glioma Cells ◽

Migration And Invasion ◽

Dependent Manner ◽

Antitumor Effects ◽

Self Renewal

Abstract Background: Although curcumol has been shown to possess antitumor effects in several cancers, its effects on glioma are largely unknown. Recently, lncRNAs have been reported to play an oncogenic role through epigenetic modifications. Therefore, here, we investigated whether curcumol inhibited glioma progression by reducing FOXD2-AS1-mediated enhancer of zeste homolog 2 (EZH2) activation.Methods: MTT, colony formation, flow cytometry, Transwell, and neurosphere formation assays were used to assess cell proliferation, cell cycle, apoptosis, the percentage of CD133+ cells, the migration and invasion abilities, and the self-renewal ability. qRT-PCR, western blotting, immunofluorescence, and immunohistochemical staining were used to detect mRNA and protein levels. Isobologram analysis and methylation-specific PCR were used to analyze the effects of curcumol on TMZ resistance in glioma cells. DNA pull-down and Chip assays were employed to explore the molecular mechanism underlying the functions of curcumol in glioma cells. Tumorigenicity was determined using a xenograft formation assay. Results: Curcumol inhibited the proliferation, metastasis, self-renewal ability, and TMZ resistance of glioma cells in vitro and in vivo. FOXD2-AS1 was highly expressed in glioma cell lines, and its expression was suppressed by curcumol treatment in a dose- and time-dependent manner. The forced expression of FOXD2-AS1 abrogated the effect of curcumol on glioma cell proliferation, metastasis, self-renewal ability, and TMZ resistance. Moreover, the forced expression of FOXD2-AS1 reversed the inhibitory effect of curcumol on EZH2 activation.Conclusions: We showed for the first time that curcumol is effective in inhibiting malignant biological behaviors and TMZ-resistance of glioma cells by suppressing FOXD2-AS1-mediated EZH2 activation on anti-oncogenes. Our findings offer the possibility of exploiting curcumol as a promising therapeutic agent for glioma treatment and may provide an option for the clinical application of this natural herbal medicine.

Protective Effect of Remdesivir Against Pulmonary Fibrosis in Mice

Frontiers in Pharmacology ◽

10.3389/fphar.2021.692346 ◽

2021 ◽

Vol 12 ◽

Author(s):

Xiaohe Li ◽

Rui Liu ◽

Yunyao Cui ◽

Jingjing Liang ◽

Zhun Bi ◽

...

Keyword(s):

Pulmonary Fibrosis ◽

Antiviral Drug ◽

Lung Damage ◽

Lung Fibroblasts ◽

Mesenchymal Transition ◽

Alveolar Epithelial ◽

Tgf Β1

Pulmonary fibrosis is a known sequela of severe or persistent lung damage. Existing clinical, imaging and autopsy studies have shown that the lungs exhibit a pathological pulmonary fibrosis phenotype after infection with coronaviruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Pulmonary fibrosis may be one of the most serious sequelae associated with coronavirus disease 2019 (COVID-19). In this study, we aimed to examine the preventative effects of the antiviral drug remdesivir on pulmonary fibrosis. We used a mouse model of bleomycin-induced pulmonary fibrosis to evaluate the effects of remdesivir on pulmonary fibrosis in vivo and further explored the potential pharmacological mechanisms of remdesivir in lung fibroblasts and alveolar epithelial cells in vitro. The preventive remdesivir treatment was started on the day of bleomycin installation, and the results showed that remdesivir significantly alleviated bleomycin-induced collagen deposition and improved pulmonary function. In vitro experiments showed that remdesivir dose-dependently suppressed TGF-β1-induced lung fibroblast activation and improved TGF-β1-induced alveolar epithelial to mesenchymal transition. Our results indicate that remdesivir can preventatively alleviate the severity of pulmonary fibrosis and provide some reference for the prevention of pulmonary fibrosis in patients with COVID-19.

Silica directly increases permeability of alveolar epithelial cells

Journal of Applied Physiology ◽

10.1152/jappl.1990.68.4.1354 ◽

1990 ◽

Vol 68 (4) ◽

pp. 1354-1359 ◽

Cited By ~ 11

Author(s):

R. K. Merchant ◽

M. W. Peterson ◽

G. W. Hunninghake

Keyword(s):

Epithelial Cells ◽

Cell Injury ◽

Alveolar Epithelium ◽

Dependent Manner ◽

Alveolar Epithelial ◽

Lactate Dehydrogenase Release ◽

Capillary Membrane

Alveolar epithelial cell injury and increased alveolar-capillary membrane permeability are important features of acute silicosis. To determine whether silica particles contribute directly to this increased permeability, we measured paracellular permeability of rat alveolar epithelium after exposure to silica, in vitro, using markers of the extracellular space. Silica (Minusil) markedly increased permeability in a dose- and time-dependent manner. This was not the result of cytolytic injury, because lactate dehydrogenase release from monolayers exposed to silica was not increased. Pretreatment of the silica with serum, charged dextrans, or aluminum sulfate blocked the increase in permeability. Scanning electron microscopy demonstrated adherence of the silica to the surface of the alveolar epithelial cells. Thus silica can directly increase permeability of alveolar epithelium.

Pneumocystis Pneumonia Increases the Susceptibility of Mice to Sublethal Hyperoxia

Infection and Immunity ◽

10.1128/iai.71.10.5970-5978.2003 ◽

2003 ◽

Vol 71 (10) ◽

pp. 5970-5978 ◽

Cited By ~ 7

Author(s):

James M. Beck ◽

Angela M. Preston ◽

Steven E. Wilcoxen ◽

Susan B. Morris ◽

Eric S. White ◽

...

Keyword(s):

T Cells ◽

Epithelial Cell ◽

Cell Injury ◽

Pulmonary Inflammation ◽

Alveolar Epithelial ◽

Epithelial Cell Injury

ABSTRACT Patients with Pneumocystis pneumonia often develop respiratory failure after entry into medical care, and one mechanism for this deterioration may be increased alveolar epithelial cell injury. In vitro, we previously demonstrated that Pneumocystis is not cytotoxic for alveolar epithelial cells. In vivo, however, infection with Pneumocystis could increase susceptibility to injury by stressors that, alone, would be sublethal. We examined transient exposure to hyperoxia as a prototypical stress that does cause mortality in normal mice. Mice were depleted of CD4+ T cells and inoculated intratracheally with Pneumocystis. Control mice were depleted of CD4+ T cells but did not receive Pneumocystis. After 4 weeks, mice were maintained in normoxia, were exposed to hyperoxia for 4 days, or were exposed to hyperoxia for 4 days followed by return to normoxia. CD4-depleted mice with Pneumocystis pneumonia demonstrated significant mortality after transient exposure to hyperoxia, while all uninfected control mice survived this stress. We determined that organism burdens were not different. However, infected mice exposed to hyperoxia and then returned to normoxia demonstrated significant increases in inflammatory cell accumulation and lung cell apoptosis. We conclude that Pneumocystis pneumonia leads to increased mortality following a normally sublethal hyperoxic insult, accompanied by alveolar epithelial cell injury and increased pulmonary inflammation.