MiR-27b suppresses epithelial–mesenchymal transition and chemoresistance in lung cancer by targeting Snail1

Abstract Heading aims MicroRNA-27b (miR-27b) has been shown to play a role in the progression of many different forms of cancer, but its specific relevance in the context of non-small cell lung cancer (NSCLC) remains uncertain. As such, this study sought to explore the role of miR-27b in NSCLC and the mechanisms whereby it functions. Materials and methods We quantified miR-27b and target gene expression via quantitative real-time PCR (RT-qPCR).We then used functional including proliferation assays, migration assay, flow cytometry, and western blotting to explore the mechanisms whereby miR-27b functions in vitro and in vivo. We additionally confirmed miR-27b target genes via luciferase reporter assay. Key findings We observed a marked decrease in miR-27b expression in NSCLC patient samples relative to paracancerous control tissues. We further found that altering miR-27b expression levels in vitro affected NSCLC tumor cell migration, proliferation, and ability to undergo epithelial-mesenchymal transition. Through the use of target prediction algorithms we identified Snail to be a miR-27b target protein that was suppressed when this miRNA was highlight expressed. Lastly, we found miR-27b expression to increase NSCLC cell sensitivity to cisplatin through its ability to target Snail. Significance Our results clearly demonstrate that miR-27b can suppress NSCLC tumor development and progression, highlighting this miR-27b/Snail1 axis as putative target for the therapeutic treatment of NSCLC.