In vitro inhibitory effects of terpenoids from Chloranthus multistachys on epithelial-mesenchymal transition via down-regulation of Runx2 activation in human breast cancer

From Chloranthus multistachys, three terpenoids - lupeol (1), henrilabdane B (2), and istanbulin A (3) were isolated. Structures of compounds were established by NMR and MS. We reported here that ISTA (3) suppressed cell invasion, but lupeol (1) and henrilabdane B (2) did not. Furthermore, ISTA significantly inhibited the ability of adhesion and migration in vitro. Next, mechanisms of ISTA-induced inhibitory effects on in vitro metastasis were investigated. Sequential treatment data revealed that ISTA dramatically inhibited EGF-induced EMT. Western blot indicated that ISTA also significantly suppressed expression of E-cadherin, vimentin, and slug. In addition, ISTA inhibited Runx2 activation and phosph-Runx2 expression. Collectively, ISTA exhibited significant inhibitory effects on in vitro metastatic potential via inducing EMT inhibition, which may be associated with inhibition of transcriptional activity of Runx2.