Cytochalasin H isolated from mangrove-derived endophytic fungus inhibits epithelial-mesenchymal transition and cancer stemness via YAP/TAZ signaling pathway in non-small cell lung cancer cells

Our previous studies have isolated cytochalasin H (CyH) from endophytic fungus derived from mangrove and found that CyH induced apoptosis and inhibited migration and angiogenesis in non-small cell lung cancer (NSCLC) cells. In this study, we further investigated the effect of CyH on epithelial-mesenchymal transition (EMT) and cancer stemness of A549 and NCI-H460 NSCLC cells and the underlying mechanisms, especially the role of YAP/ TAZ signaling pathway in the process. Our results showed that CyH significantly inhibited invasive ability and the sphere formation of NSCLC cells. The expression of E-cadherin, an EMT epithelial marker, was obviously up-regulated, while the expression of Vimentin and N-cadherin, the EMT mesenchymal markers, was dramatically down-regulated by CyH treatment in NSCLC cells. Moreover, the expression of EMT-associated transcription factors including Slug, Twist1, and Snail1 and stemness markers including Nanog, Sox-2, and Oct-4 was significantly down-regulated by CyH treatment in NSCLC cells. Additionally, CyH significantly down-regulated YAP and TAZ expression and up-regulated LAST1/2 and MST1/2 expression, and CyH inhibited the interaction between YAP and TEAD. Furthermore, YAP knockdown abolished the effect of CyH on the expression of EMT- and stemness-related markers in NSCLC cells. Taken together, these results suggest that CyH inhibits EMT and cancer stemness of NSCLC cells via the regulation of YAP/TAZ signaling pathway.