Purpose: MicroRNAs (miRNAs) are a group of small non-coding RNAs involved in different cancers, including lung cancer. Here, we aim to investigate the expression profiles of circulating miRNAs and their roles contributed to the progress of lung cancer.
Materials and methods: The levels of circulating miRNA in lung cancer patients were investigated by miRNAs assay. Then we predicted the target genes of aberrantly expressing miRNAs by searching genetic databases. Based on the A549 cells transfected with miR-1246 mimics or miR-1246 inhibitor,we further measured the roles of miR-1246 involving in the epithelial-mesenchymal transition (EMT), migration and invasion capacities of lung cancer cells in vitro. Finally, we detected the effects of miR-1246 on glycogen synthase kinase-3β (GSK-3β)/β-catenin pathway by immunofluorescence and Western blot, respectively.
Results: We identified that 14 miRNAs were aberrantly expressed in the serum of lung cancer patients. Among them, miR-1246 was the most up-regulated. The cell assays indicated that miR-1246 significantly increased the migration and invasion capabilities of A549 lung cancer cells. Meanwhile, immunofluorescence analysis revealed that miR-1246 promoted EMT process of A549 cells accompanying with decreasing E-cadherin expression, while increasing vimentin and transforming growth factor β (TGF-β) expression. Furthermore, an online tool predicated that miR-1246 might bind to 3'-untranslated region of GSK-3β, which was confirmed by overexpression and knockdown of miR-1246 assays.
Conclusion: Taken together, the study illustrates that miR-1246 regulates Wnt/β-catenin pathway through targeting GSK-3β/β-catenin, which partly contributing to tumor metastasis. MiR-1246 may play an essential role in the diagnosis and therapeutic of lung cancer.
Keywords: Epithelial–mesenchymal transition; Glycogen synthase kinase 3β; Lung neoplasms; Metastasis; MiR-1246; β-catenin.