An Organobismuth Compound that Exhibits Selective Cytotoxicity to Vascular Endothelial Cells in Vitro

Abstract

Selective cytotoxicity of chemical compounds to vascular endothelial cells is often beneficial for clinical applications including antivascular cancer therapy. In this study, the cytotoxicity of 35 organic compounds containing bismuth or antimony was evaluated based on the leakage of lactate dehydrogenase and morphologic observations in cultured bovine aortic endothelial cells and other cell types. The results indicate that only tris[2-(N,N-dimethylaminomethyl)phenyl]-bismuthane (TDPBi) had potent cytotoxicity to bovine aortic endothelial cells but not to bovine aortic smooth muscle cells and porcine kidney epithelial LLC-PK₁ cells; the compound exhibited moderate cytotoxicity to human fetal lung fibroblastic IMR-90 cells. Neither inorganic bismuth nor tris[2-(N,N-dimethylaminomethyl)phenyl]stibane, in which antimony substitutes for bismuth with the same organic structure as TDPBi, exhibited cytotoxicity to vascular endothelial cells, suggesting that the entire structure of TDPBi is required for selective cytotoxicity. The present data revealed that TDPBi has selective cytotoxicity to vascular endothelial cells, which may be applicable in antivascular cancer therapy.