The Acetylenic Tricyclic Bis(cyano enone), TBE-31 Inhibits Non-Small Cell Lung Cancer Cell Migration through Direct Binding with Actin

The migratory and invasive potential of the epithelial-derived tumor cells depends on epithelial-to-mesenchymal transition (EMT) as well as the reorganization of the cell cytoskeleton. Here, we show that the tricyclic compound acetylenic tricyclic bis(cyano enone), TBE-31, directly binds to actin and inhibits linear and branched actin polymerization in vitro. Furthermore, we observed that TBE-31 inhibits stress fiber formation in fibroblasts as well as in non-small cell lung cancer cells during TGF beta-dependent EMT. Interestingly, TBE-31 does not interfere with TGF beta-dependent signaling or changes in E-cadherin and N-cadherin protein levels during EMT. Finally, we observed that TBE-31 inhibits fibroblast and non-small cell lung tumor cell migration with an IC50 of 1.0 and 2.5 mu mol/L, respectively. Taken together, our results suggest that TBE-31 targets linear actin polymerization to alter cell morphology and inhibit cell migration. (C)2014 AACR.