Effect of the alteration of Tribbles homologue 3 expression on epithelial­mesenchymal transition of transforming growth factor ß1­induced mouse alveolar epithelial cells through the Wnt/ß­catenin signaling pathway.

ABSTRACT

The aims of the present study were to elucidate the regulatory effect of exogenous Tribbles homologue 3 (TRB3) expression on the Wnt/ß­catenin signaling pathway and epithelial­mesenchymal transition (EMT) in transforming growth factor­ß1 (TGF­ß1)­induced mouse alveolar epithelial cells (MLE­12) and investigate the underlying regulatory mechanisms. TRB3 expression was upregulated and downregulated using gene overexpression and RNA interference techniques, respectively. TGF­ß1­stimulated MLE­12 cells were examined for EMT and activation condition of the Wnt/ß­catenin signaling pathway using Cell Counting Kit­8, flow cytometry, western blotting, reverse transcription­quantitative PCR, ELISA and immunofluorescence techniques. During TGF­ß1­induced EMT, TRB3 expression was found to be significantly upregulated (P<0.05). In the TRB3 overexpression group, upregulated expression of ß­catenin and EMT­related genes and proteins was observed (P<0.05), and an increase in fibrosis­related factors in the cell culture supernatant was detected (P<0.05); however, the results were the opposite in the TRB3 downregulated group (P<0.05). TRB3 may be involved in the regulation of EMT in TGF­ß1­induced MLE­12 cells through the Wnt/ß­catenin signaling pathway.