scholarly journals Bleomycin (BLM) Induces Epithelial-to-Mesenchymal Transition in Cultured A549 Cells via the TGF-β/Smad Signaling Pathway

2016 ◽  
Vol 7 (11) ◽  
pp. 1557-1564 ◽  
Author(s):  
Kui-Jun Chen ◽  
Qing Li ◽  
Cang-mei Wen ◽  
Zhao-Xia Duan ◽  
Jie yuan Zhang ◽  
...  
2018 ◽  
Vol 50 (2) ◽  
pp. 757-767 ◽  
Author(s):  
Qiu-Yue Tan ◽  
Zhen-Shun  Cheng

Backgrounds/Aims: Epithelial-to-mesenchymal transition (EMT) has been proven to be involved in development and progression of pulmonary fibrosis. This study aims to investigate the role of transforming growth factor β1 (TGFβ1)-smad signaling pathway in the interleukin-33 (IL-33) induced EMT. Methods: The human type II alveolar epithelial cell line, A549, and small airway epithelial cells (SAEC) were cultured and divided into 4 groups including Control, LY-2109761 (TGFβ receptor inhibitor), IL-33 and IL-33+LY-2109761 group. Expression of TGFβ1, E-cadherin (E-cad) and α-smooth muscle actin (α-SMA) were examined by using real-time PCR (RT-PCR) and western blot assay, respectively. The smad3 signaling pathway factors, including smad3 and phosphorylated smad3 (p-smad3), were also detected by using western blot assay. Results: IL-33 significantly activated T1/ST2 expression in A549 cells (P< 0.05). TGFβ1 receptor inhibitor significantly suppressed the IL-33 caused down-expression of E-cad compared to IL-33 alone (P< 0.05). IL-33 significantly increased the α-SMA levels compared to Control group (P< 0.05) and TGFβ1 receptor inhibitor inhibited the other effects of IL-33. IL-33 significantly enhanced the levels of TGFβ1 compared to Control group (P< 0.05). TGFβ1 receptor inhibitor suppressed the IL-33 induced up-expression of p-smad3. Conclusion: The TGFβ1-smad signaling pathway participates in the IL-33 induced epithelial-to-mesenchymal transition of A549 cells.


2015 ◽  
Vol 37 (1) ◽  
pp. 43-54 ◽  
Author(s):  
Lu Zhang ◽  
Zhenghong Li ◽  
Weiming He ◽  
Lingdong Xu ◽  
Jing Wang ◽  
...  

Background/Aims: To investigate the effect of Astragaloside IV (AS-IV) on the regulation of the TGF-β1/Smad signaling pathway in peritoneal mesothelial cells with an epithelial-to-mesenchymal transition (EMT). Methods: EMT of human peritoneal mesothelial cells (HMrSV5) was induced using 2 ng/ml TGF-β1. Cells were randomly divided into a vehicle group, a vehicle group with AS-IV, a TGF-β1 treated group, and a TGF-β1 treated group receiving varied doses of AS-IV or NAC. Real-time quantitative PCR and western blot were used to detect the expression of genes and proteins associated with the TGF-β1/Smad signaling pathway and EMT. DCFH-DA was used to detect the generation of ROS in HMrSV5 cells, and a transwell migration assay was used to verify the capacity of AS-IV to inhibit EMT in HMrSV5 cells. Lentiviruses were used as carriers for the overexpression or knockdown of the Smad7 gene. Results: Expression levels of E-cadherin (epithelial marker) was decreased and vimentin, α-SMA (EMT markers) and collagen I (extracellular matrix protein) phospho-Smad2/3, Snail1 and Snail2 was increased significantly in the TGF-β1-treated HMrSV5 cells. AS-IV was associated with downregulated expression of vimentin and phospho-Smad2/3 in a dose-dependent manner, while the expression of Smad7 increased. Silenced or forced expression of Smad7 verified its role in the inhibitory effect of AS-IV on TGF-β1-induced EMT in HMrSV5 cells. Conclusion: AS-IV effectively promotes the upregulation of Smad7 in the TGF-β1/Smad signaling pathway during the EMT of HMrSV5 cells, indicating its potential therapeutic effect for the control of PF.


2018 ◽  
Vol 46 (5) ◽  
pp. 1895-1906 ◽  
Author(s):  
Hanqing Hu ◽  
Meng Wang ◽  
Hongwei Wang ◽  
Zheng Liu ◽  
Xu Guan ◽  
...  

Background/Aims: Colorectal cancer (CRC) is a malignancy that has high morbidity and mortality and is initiated from accumulative genetic events. Although much effort has been made to elucidate the genetic mechanism underlying this disease, it still remains unknown. Here, we discovered a novel role for multiple epidermal growth factor-like domains protein 6 (MEGF6) in CRC, namely, that it induces the epithelial-to-mesenchymal transition (EMT) to promote CRC metastasis via the transforming growth factor beta (TGFβ)/SMAD signaling pathway. Methods: RNA sequencing data from the Gene Expression Omnibus database were analyzed using R software. Based on The Cancer Genome Atlas Colon Adenocarcinoma (TCGA-COAD) cohort, the clinical significance of MEGF6 was investigated. HCT8R, HCT116, and LoVo CRC cells were transfected with small interfering RNA against MEGF6, and their proliferation and sensitivity to fluorouracil were evaluated with the MTT cell proliferation and colony formation assays. Proteins associated with cell growth were detected by western blot analysis. The apoptosis of cells was evaluated by Annexin V/propidium iodide staining, and transwell assays were performed to assess the involvement of MEGF6 in cell migration. Markers of EMT and TGFβ/SMAD signaling were evaluated by quantitative PCR and western blotting, and the correlation between MEGF6 and these markers was assessed in the TCGA colon and renal adenocarcinoma cohort. Results: The results showed that MEGF6 was upregulated in HCT8R cells. In addition, MEGF6 was significantly overexpressed in tumor tissue and predicted a poor survival in the TCGA-COAD cohort. Moreover, MEGF6 accelerated CRC cell growth and inhibited apoptosis, and promoted CRC metastasis by inducing the EMT. Finally, we found that TGFβ/SMAD signaling triggered the expression of Slug, which regulates the MEGF6-mediated EMT. Conclusions: MEGF6 may serve as an oncogene to promote cell proliferation and inhibit apoptosis. MEGF6 can also accelerate cell migration via TGFβ/SMAD signaling-mediated EMT.


2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Huajun Wang ◽  
Guangying Zheng

Abstract Background Abnormal proliferation, metastasis and epithelial-mesenchymal transformation (EMT) of lens epithelial cells (LECs) are direct factors of posterior capsular opacification (PCO). Nuclear enriched abundant transcript 1 (NEAT1) has been shown to promote cell proliferation, metastasis and EMT, but whether it affects the progression of PCO is unclear. Methods The expression of NEAT1, microRNA-486-5p (miR-486-5p) and Drosophila mothers against decapentaplegic 4 (SMAD4) was determined using quantitative real-time polymerase chain reaction (qRT-PCR). The proliferation of cells was measured via 3-(4, 5-dimethyl-2 thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Transwell assay was employed to detect the migration and invasion of cells. The levels of EMT marker proteins, SMAD4 protein and transforming growth factor-β (TGF-β)/SMAD signaling pathway-related proteins were assessed by western blot (WB) analysis. Further, the relationship between miR-486-5p and NEAT1 or SMAD4 was confirmed by dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay and biotin-labeled RNA pull-down assay. Results NEAT1 is upregulated and miR-486-5p is downregulated in the posterior capsular tissues of PCO patients and TGF-β2-induced LECs. Interference of NEAT1 reverses the promoting effect of TGF-β2 on the proliferation, migration, invasion and EMT of LECs. MiR-486-5p can be sponged by NEAT1, and its inhibitor reverses the suppression effect of NEAT1 silencing on the progression of TGF-β2-induced LECs. SMAD4 functions as a target of miR-486-5p, and its overexpression recovers the inhibition effect of miR-486-5p overexpression on the progression of TGF-β2-induced LECs. The activity of the TGF-β/SMAD signaling pathway is regulated by the NEAT1/miR-486-5p/SMAD4 axis. Conclusion Our study shows that NEAT1 has a positive effect on the progression of PCO and is expected to become a new target for PCO treatment.


2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Haiyan Xu ◽  
Xu Wang ◽  
Mingming Liu ◽  
Xueyuan He

This study discussed the effect of Tangzhiqing granules on podocyte epithelial-mesenchymal transition in kidney of diabetic rats. The diabetic rats were divided randomly into five groups: DM group treated with vehicle, Tangzhiqing granules low-dose treatment group, Tangzhiqing granules middle-dose treatment group, and Tangzhiqing granules high-dose treatment group. Eight Wistar rats used as control group were given saline solution. The intervention was all intragastric administration for 8 weeks. At the end of the 8 weeks, biochemical parameters and kidney weight/body weight ratio were measured. The kidney tissues were observed under light microscope and transmission electron microscopy. To search for the underlying mechanism, we examined the epithelial-to-mesenchymal transition (EMT) related molecular markers and TGF-β/smad signaling pathway key proteins expression. The results showed that Tangzhiqing granules relieved the structural damage and functional changes of diabetic kidneys. Kidney podocyte EMT related molecular markers nephrin and CD2AP expression were increased, when desmin and α-SMA levels were decreased by Tangzhiqing granules in diabetic rats. Further TGF-β/smad signaling pathway key proteins TGF-β1 and p-smad2/3 levels were decreased in diabetic rats after treatment with Tangzhiqing granules. These findings suggest that Tangzhiqing granules may protect the podocytes of diabetic nephropathy rats via alleviating podocyte EMT and likely activating TGFβ/smad signaling pathway.


Sign in / Sign up

Export Citation Format

Share Document