Gene

Cell biology

Molecular biology

A549 cell

Biology

Transforming growth factor

SMAD

Cell migration

Extracellular matrix

Vimentin

Cancer research

Biochemistry

Downregulation and upregulation

Immunology

Epithelial–mesenchymal transition

Fibronectin

Chemistry

Cell

Immunohistochemistry

American Journal of Rhinology and Allergy

Purpose Doxycycline has antibacterial and anti-inflammatory effects, and it also suppresses collagen biosynthesis. This study aimed to confirm the effects and mechanism of doxycycline on transforming growth factor (TGF) beta 1 induced epithelial-mesenchymal transition and cell migration in A549 and primary nasal epithelial cells. Methods A 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide assay and phalloidin-fluorescein isothiocyanate staining were used to evaluate cytotoxicity and cellular morphologic changes. Western blot and immunofluorescence staining were used to determine the expression levels of E-cadherin, vimentin, alpha-smooth muscle actin, fibronectin, phosphorylated Smad2/3, and mitogen-activated protein kinases. Scratch and transwell migration assays were used to assess cellular migration ability. Results Doxycycline (0-10 μg/mL) had no significant cytotoxic effects in A549 and primary nasal epithelial cells. Increased expression of mesenchymal markers, including vimentin, alpha-smooth muscle actin, and fibronectin in TGF beta 1 induced A549 cells were downregulated by doxycycline treatment. In contrast, E-cadherin expression was upregulated in TGF beta 1 induced A549 cells. An in vitro cell migration assay showed that doxycycline also inhibited the ability of TGF beta 1 induced migration. Doxycycline treatment suppressed the activation of Smad2/3 and p38, whereas its inhibitory effects were similar to each element-specific inhibitor in A549 and primary nasal epithelial cells. Conclusion Doxycycline inhibited TGF beta 1 induced epithelial-to-mesenchymal transition and migration by targeting Smad2/3 and p38 signal pathways in respiratory epithelial cells.

Effect of Doxycycline on Epithelial-Mesenchymal Transition<i>via</i>the p38/Smad Pathway in Respiratory Epithelial Cells

Effect of Doxycycline on Epithelial-Mesenchymal Transitionviathe p38/Smad Pathway in Respiratory Epithelial Cells