Activation of HGF/c-Met signaling by ultrafine carbon particles and its contribution to alveolar type II cell proliferation

2012 ◽  
Vol 302 (8) ◽  
pp. L755-L763 ◽  
Author(s):  
Chih-Ching Chang ◽  
Jia-Jhen Chiu ◽  
Shan-Ling Chen ◽  
Hui-Chun Huang ◽  
Hui-Fen Chiu ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Kinase Inhibitor ◽  
Carbon Particle ◽  
Alveolar Type ◽  
Type Ii ◽  
Type Ii Cell ◽  
Met Phosphorylation

Hepatocyte growth factor (HGF) is a potent mitogen and motogen for various epithelial cells. The present study aimed to explore the role of HGF and c-Met receptor in ultrafine carbon particle-induced alveolar type II epithelial (type II) cell proliferation. ICR mice were intratracheally instilled with 100 μg ultrafine carbon black (ufCB) and killed at 21, 48, and 72 days postexposure to examine type II cell proliferation, HGF release, and c-Met activation. In vivo and in vitro applications of neutralizing anti-HGF antibody were used to investigate the causal role of HGF in cell proliferation. The Met kinase inhibitor SU11274 and extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor PD98059 were used to delineate the involvement of c-Met/ERK1/2 in rat L2 pulmonary epithelial cell proliferation. The results demonstrated that in vivo exposure to 100 μg ufCB caused increased HGF in bronchoalveolar lavage fluid, as well as increased HGF production, c-Met phosphorylation, and cell proliferation in type II cells. In vitro study revealed that ufCB caused a dose-dependent increase in HGF release, c-Met phosphorylation, and cell proliferation. Importantly, treatment with the neutralizing anti-HGF antibody significantly blocked ufCB-induced in vivo and in vitro type II cell proliferation. Moreover, SU11274 and PD98059 significantly reduced ufCB-increased L2 cell proliferation. Results from Western blotting demonstrated that SU11274 successfully suppressed ufCB-induced phosphorylation of c-Met and ERK1/2. In summary, the activation of HGF/c-Met signaling is a major pathway involved in ufCB-induced type II cell proliferation.

Inhibition of alveolar type II cell ATP and surfactant synthesis by nitric oxide

1996 ◽  
Vol 270 (6) ◽  
pp. L898-L906 ◽  
Author(s):  
I. Y. Haddad ◽  
S. Zhu ◽  
J. Crow ◽  
E. Barefield ◽  
T. Gadilhe ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Lipid Synthesis ◽  
Alveolar Epithelium ◽  
Alveolar Type ◽  
Type Ii ◽  
Surfactant Synthesis ◽  
Cell Energy ◽  
Type Ii Cell

Alveolar type II (ATII) cells, are often exposed to increased concentration of endogenous and exogenous nitric oxide (.NO). Exposure of freshly isolated rat ATII cells for 2 h to 1-3 microM .NO, generated by S-nitroso-N-penicillamine (SNAP), spermine NONOate, or 3-morpholino-sydnonimine (SIN-1) in the presence of superoxide dismutase, resulted in approximately 60% decrease in the rate of surfactant synthesis, as measured by the rate of incorporation of [methyl-3H]choline into phosphatidylcholine, and 60-80% inhibition of cellular ATP levels, as determined by bioluminescence. Similar results were obtained after incubation of ATII cells with authentic peroxynitrite (0.5 mM) but not SIN-1, a putative generator of peroxynitrite. Addition into the medium of oxyhemoglobin (20 microM), which scavenged .NO, or enhancement of ATII glutathione levels by preincubation with glutathione ester (5 mM) totally prevented the NONOate (100 microM) inhibition of cellular ATP. In contrast to the in vitro findings, normal levels of ATP and lipid synthesis were measured in ATII cells isolated from the lungs of rats that breathed .NO gas (80 ppm) in 21% O2 for 2 h (n = 4). This lack of effect may be due either to the presence of various antioxidants (such as glutathione) in the epithelial lining fluid or to the relatively low concentrations of .NO reaching the alveolar epithelium. We conclude that .NO and peroxynitrite, at concentrations likely to be encountered in vivo during inflammation, decrease ATII cell energy stores and surfactant synthesis, which may lead to derangement of important physiological functions.

scholarly journals KLF7/VPS35 axis contributes to hepatocellular carcinoma progression through CCDC85C-activated β-catenin pathway

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yarong Guo ◽  
Bao Chai ◽  
Junmei Jia ◽  
Mudan Yang ◽  
Yanjun Li ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Proliferation ◽  
Tumor Growth ◽  
Luciferase Reporter ◽  
Aberrant Expression ◽  
Proliferation And Invasion ◽  
Hcc Cells

Abstract Objective Dysregulation of KLF7 participates in the development of various cancers, but it is unclear whether there is a link between HCC and aberrant expression of KLF7. The aim of this study was to investigate the role of KLF7 in proliferation and migration of hepatocellular carcinoma (HCC) cells. Methods CCK8, colony growth, transwell, cell cycle analysis and apoptosis detection were performed to explore the effect of KLF7, VPS35 and Ccdc85c on cell function in vitro. Xenografted tumor growth was used to assess in vivo role of KLF7. Chip-qPCR and luciferase reporter assays were applied to check whether KLF7 regulated VPS35 at transcriptional manner. Co-IP assay was performed to detect the interaction between VPS35 and Ccdc85c. Immunohistochemical staining and qRT-PCR analysis were performed in human HCC sampels to study the clinical significance of KLF7, VPS35 and β-catenin. Results Firstly, KLF7 was highly expressed in human HCC samples and correlated with patients’ differentiation and metastasis status. KLF7 overexpression contributed to cell proliferation and invasion of HCC cells in vitro and in vivo. KLF7 transcriptional activation of VPS35 was necessary for HCC tumor growth and metastasis. Further, co-IP studies revealed that VPS35 could interact with Ccdc85c in HCC cells. Rescue assay confirmed that overexpression of VPS35 and knockdown of Ccdc85c abolished the VPS35-medicated promotion effect on cell proliferation and invasion. Finally, KLF7/VPS35 axis regulated Ccdc85c, which involved in activation of β-catenin signaling pathway, confirmed using β-catenin inhibitor, GK974. Functional studies suggested that downregulation of Ccdc85c partly reversed the capacity of cell proliferation and invasion in HCC cells, which was regulated by VPS35 upregulation. Lastly, there was a positive correlation among KLF7, VPS35 and active-β-catenin in human HCC patients. Conclusion We demonstrated that KLF7/VPS35 axis promoted HCC cell progression by activating Ccdc85c-medicated β-catenin pathway. Targeting this signal axis might be a potential treatment strategy for HCC.

Differential Effects of Halothane and Thiopental on Surfactant Protein C Messenger RNA  In Vivo and  In Vitro in Rats 

2000 ◽  
Vol 93 (3) ◽  
pp. 805-810 ◽  
Author(s):  
Catherine Paugam-Burtz ◽  
Serge Molliex ◽  
Bernard Lardeux ◽  
Corinne Rolland ◽  
Michel Aubier ◽  
...  
Keyword(s):  
Messenger Rna ◽  
Protein C ◽  
Alveolar Type ◽  
Type Ii Cells ◽  
Type Ii ◽  
Alveolar Type Ii Cells ◽  
Mechanically Ventilated ◽  
Mrna Content

Background Pulmonary surfactant is a complex mixture of proteins and phospholipids synthetized by alveolar type II cells. Volatile anesthetics have been shown to reduce surfactant phospholipid biosynthesis by rat alveolar type II cells. Surfactant-associated protein C (SP-C) is critical for the alveolar surfactant functions. Our goal was to evaluate the effects of halothane and thiopental on SP-C messenger RNA (mRNA) expression in vitro in rat alveolar type II cells and in vivo in mechanically ventilated rats. Methods In vitro, freshly isolated alveolar type II cells were exposed to halothane during 4 h (1, 2, 4%) and 8 h (1%), and to thiopental during 4 h (10, 100 micrometer) and 8 h (100 micrometer). In vivo, rats were anesthetized with intraperitoneal thiopental or inhaled 1% halothane and mechanically ventilated for 4 or 8 h. SP-C mRNA expression was evaluated by ribonuclease protection assay. Results In vitro, 4-h exposure of alveolar type II cells to thiopental 10 and 100 micrometer increased their SP-C mRNA content to 145 and 197%, respectively, of the control values. In alveolar type II cells exposed for 4 h to halothane 1, 2, and 4%, the SP-C mRNA content increased dose-dependently to 160, 235, and 275%, respectively, of the control values. In vivo, in mechanically ventilated rats, 4 h of halothane anesthesia decreased the lung SP-C mRNA content to 53% of the value obtained in control (nonanesthetized, nonventilated) animals; thiopental anesthesia increased to 150% the lung SP-C mRNA content. Conclusions These findings indicate that halothane and thiopental used at clinically relevant concentrations modulate the pulmonary SP-C mRNA content in rats. In vivo, the additive role of mechanical ventilation is suggested.

scholarly journals Enhanced phosphorylation of Na+–Cl− co-transporter in experimental metabolic syndrome: role of insulin

2012 ◽  
Vol 123 (11) ◽  
pp. 635-647 ◽  
Author(s):  
Radko Komers ◽  
Shaunessy Rogers ◽  
Terry T. Oyama ◽  
Bei Xu ◽  
Chao-Ling Yang ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Time Course ◽  
Kinase Inhibitor ◽  
Endogenous Expression ◽  
The Metabolic Syndrome ◽  
Mammalian Cell Lines ◽  
Phosphoinositide 3 Kinase

In the present study, we investigated the activity of the thiazide-sensitive NCC (Na+–Cl− co-transporter) in experimental metabolic syndrome and the role of insulin in NCC activation. Renal responses to the NCC inhibitor HCTZ (hydrochlorothiazide), as a measure of NCC activity in vivo, were studied in 12-week-old ZO (Zucker obese) rats, a model of the metabolic syndrome, and in ZL (Zucker lean) control animals, together with renal NCC expression and molecular markers of NCC activity, such as localization and phosphorylation. Effects of insulin were studied further in mammalian cell lines with inducible and endogenous expression of this molecule. ZO rats displayed marked hyperinsulinaemia, but no differences in plasma aldosterone, compared with ZL rats. In ZO rats, natriuretic and diuretic responses to NCC inhibition with HCTZ were enhanced compared with ZL rats, and were associated with a decrease in BP (blood pressure). ZO rats displayed enhanced Thr53 NCC phosphorylation and predominant membrane localization of both total and phosphorylated NCC, together with a different profile in expression of SPAK (Ste20-related proline/alanine-rich kinase) isoforms, and lower expression of WNK4. In vitro, insulin induced NCC phosphorylation, which was blocked by a PI3K (phosphoinositide 3-kinase) inhibitor. Insulin-induced reduction in WNK4 expression was also observed, but delayed compared with the time course of NCC phosphorylation. In summary, we report increased NCC activity in hyperinsulinaemic rodents in conjunction with the SPAK expression profile consistent with NCC activation and reduced WNK4, as well as an ability of insulin to induce NCC stimulatory phosphorylation in vitro. Together, these findings indicate that hyperinsulinaemia is an important driving force of NCC activity in the metabolic syndrome with possible consequences for BP regulation.

scholarly journals circATP2A2 promotes osteosarcoma progression by upregulating MYH9

Open Medicine ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. 1749-1761
Author(s):  
Xin Cao ◽  
Xianfeng Meng ◽  
Peng Fu ◽  
Lin Wu ◽  
Zhen Yang ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Area Under Curve ◽  
Prognostic Biomarker ◽  
Migration And Invasion ◽  
Promising Target ◽  
Repressive Effect ◽  
Cell Malignancy

Abstract Osteosarcoma (OS) is a highly metastatic primary malignant tumor. CircRNA hsa_circ_0028173 (circATP2A2) has been uncovered to be related to the advancement of OS. However, the biological role of circATP2A2 in OS has not been validated. circATP2A2 and MYH9 were upregulated while miR-335-5p was downregulated in OS. OS patients with high circATP2A2 expression displayed a shorter overall survival and the area under curve of circATP2A2 was 0.77, manifesting that circATP2A2 might be a diagnostic and prognostic biomarker. circATP2A2 silencing repressed OS cell proliferation and glycolysis in vivo and constrained OS cell proliferation, glycolysis, migration, and invasion in vitro. circATP2A2 regulated MYH9 expression through sponging miR-335-5p. MiR-335-5p inhibitor reversed the repressive effect of circATP2A2 knockdown on OS cell malignancy and glycolysis. MYH9 overexpression overturned miR-335-5p upregulation-mediated OS cell malignancy and glycolysis. circATP2A2 accelerated OS cell malignancy and glycolysis through upregulating MYH9 via sponging miR-335-5p, offering a promising target for OS treatment.

scholarly journals HNRNPA2B1 promotes multiple myeloma progression by increasing AKT3 expression via m6A-dependent stabilization of ILF3 mRNA

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Fengjie Jiang ◽  
Xiaozhu Tang ◽  
Chao Tang ◽  
Zhen Hua ◽  
Mengying Ke ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Cell Proliferation ◽  
Cellular Proliferation ◽  
Aberrant Expression ◽  
The Stability ◽  
Induced Apoptosis ◽  
Proliferation In Vitro

AbstractN6-methyladenosine (m6A) modification is the most prevalent modification in eukaryotic RNAs while accumulating studies suggest that m6A aberrant expression plays an important role in cancer. HNRNPA2B1 is a m6A reader which binds to nascent RNA and thus affects a perplexing array of RNA metabolism exquisitely. Despite unveiled facets that HNRNPA2B1 is deregulated in several tumors and facilitates tumor growth, a clear role of HNRNPA2B1 in multiple myeloma (MM) remains elusive. Herein, we analyzed the function and the regulatory mechanism of HNRNPA2B1 in MM. We found that HNRNPA2B1 was elevated in MM patients and negatively correlated with favorable prognosis. The depletion of HNRNPA2B1 in MM cells inhibited cell proliferation and induced apoptosis. On the contrary, the overexpression of HNRNPA2B1 promoted cell proliferation in vitro and in vivo. Mechanistic studies revealed that HNRNPA2B1 recognized the m6A sites of ILF3 and enhanced the stability of ILF3 mRNA transcripts, while AKT3 downregulation by siRNA abrogated the cellular proliferation induced by HNRNPA2B1 overexpression. Additionally, the expression of HNRNPA2B1, ILF3 and AKT3 was positively associated with each other in MM tissues tested by immunohistochemistry. In summary, our study highlights that HNRNPA2B1 potentially acts as a therapeutic target of MM through regulating AKT3 expression mediated by ILF3-dependent pattern.

scholarly journals KIF4A Regulates the Progression of Pancreatic Ductal Adenocarcinoma through Proliferation and Invasion

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Jing Chen ◽  
Cui-Cui Zhao ◽  
Fei-Ran Chen ◽  
Guo-Wei Feng ◽  
Fei Luo ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Cell Proliferation ◽  
Pancreatic Ductal Adenocarcinoma ◽  
Disease Free Survival ◽  
High Expression ◽  
Ductal Adenocarcinoma ◽  
Migration And Invasion

Background. Pancreatic cancer is a malignant tumor of the digestive tract, which is difficult to diagnose and treat due to bad early diagnosis. We aimed to explore the role of kinesin superfamily 4A (KIF4A) in pancreatic ductal adenocarcinoma (PDAC). Methods. We first used the bioinformatic website to screen the data of pancreatic cancer in TCGA, and KIF4A protein was detected among the 86 specimens of patients in our hospital combined with clinic-pathological characteristics and survival analysis. KIF4A loss-expression cell lines were established by RNA interference (RNAi). In addition, we performed in vitro cell assays to detect the changes in cell proliferation, migration, and invasion. The proteins involved in the proliferation and metastasis of cancer cells were also detected by western blot. The above results could be proved in vivo. Further, the correlation between KIF4A and CDC5L was analyzed by TCGA and IHC data. Results. We first found a high expression of KIF4A in pancreatic cancer, suggesting a role of KIF4A in the development of pancreatic cancer. KIF4A was found to be differentially expressed ( P < 0.05 ) among the 86 specimens of patients in our hospital and was significantly associated with PDAC TNM stages and tumor size. High KIF4A expression also significantly worsened overall survival (OS) and disease-free survival rate (DFS) ( P < 0.05 , respectively). In addition, cell proliferation, migration, and invasion were inhibited by the KIF4A-shRNA group compared with the control ( P < 0.05 , respectively). In the end, knockdown of KIF4A could inhibit tumor development and metastasis in vivo. Further, the positive correlation between KIF4A and CDC5L existed, and KIF4A might promote pancreatic cancer proliferation by affecting CDC5L expression. Conclusion. In conclusion, the high expression level of KIF4A in PDAC was closely related to poor clinical and pathological status, lymphatic metastasis, and vascular invasion. KIF4A might be involved in promoting the development of PDAC in vitro and in vivo, which might be a new therapeutic target of PDAC.

Kallistatin Inhibits Endothelial Cell Proliferation, Migration and Adhesion in Vitro and Angiogenesis in the Ischemic Hindlimb of Rats

Hypertension ◽  
2000 ◽  
Vol 36 (suppl_1) ◽  
pp. 706-707
Author(s):  
Robert Q Miao ◽  
Jun Agata ◽  
Lee Chao ◽  
Julie Chao
Keyword(s):  
Cell Proliferation ◽  
Endothelial Cell ◽  
Gene Delivery ◽  
Fluorescent Protein ◽  
Regional Blood Flow ◽  
Endothelial Cell Proliferation ◽  
Hek 293

P76 Kallistatin is a serine proteinase inhibitor (serpin) which has multifunctions including regulation of tissue kallikrein activity, blood pressure, inflammation and neointima hyperplasia. In this study, we investigated the potential role of kallistatin in vascular biology by studying its effects on the proliferation, migration and adhesion of cultured primary human endothelial cells in vitro, and angiogenesis in the ischemic hindlimb of rats. Purified kallistatin significantly inhibits cultured endothelial cell proliferation, migration and adhesion induced by VEGF or bFGF. To further investigate the role of kallistatin in vascular growth in vivo, we prepared adenovirus carrying the human kallistatin gene under the control of the cytomegalovirus promoter/enhancer (Ad.CMV-cHKBP). Expression of recombinant human kallistatin in HEK 293 cells transfected with Ad.CMV-cHKBP was identified by a specific ELISA. The effect of adenovirus-mediated kallistatin gene delivery on angiogenesis was evaluated in a rat model of hindlimb ischemia. Adenovirus carrying the human kallistatin or green fluorescent protein (GFP) gene were injected locally into the ischemic adductor at the time of surgery. Histological and morphometric analysis at 14 days post injection showed that adenovirus-mediated kallistatin gene delivery significantly reduced capillary density in the ischemic muscle as compared to that of control rats injected with GFP. The anti-angiogenic effect of kallistatin was associated with reduced regional blood flow in the ischemic hindlimb measured by microsphere assays. Expression of human kallistatin was identified in the injected muscle and immunoreactive human kallistatin levels were measured in the muscle and in the circulation of rats following kallistatin gene delivery. These results demonstrate a novel role of kallistatin in the inhibition of angiogenesis and in vascular remodeling.

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