Downregulation of SATB2 is critical for induction of epithelial-to-mesenchymal transition and invasion of NSCLC cells

In this study, we investigated the regulatory role of SATB2 expression in TGF-β-induced EMT and invasion of NSCLC cells, and found that SATB2 is downregulated in A549 cells and TGF-β can induce EMT in these cells, however, TGF-β can not induce EMT in SATB2 expressing cells such as H1650, PC3, II-18, Hcc78 and Hcc193. Our results demonstrated that SATB2 knockdown is sufficient to induce generation of fibroblast-like morphology, EMT and invasion of NSCLC cells by upregulating the expressions of Slug, Twist and Zeb1. Moreover, SATB2 knockdown promotes TGF-β-induced EMT and invasion in NSCLC cells. These results strongly suggest that SATB2 prevents induction of EMT by suppressing expression of EMT-inducing transcription factors in NSCLC cells. Furthermore, SATB2 could inhibit tumour initiation by suppressing stemness marker genes such as CD44, Nanog, Oct-4A and Sox-2. Consequently, our results clearly indicate that SATB2 plays pivotal role in EMT, invasion and stemness of NSCLC cells.