Effect of zinc ion on polymerization and cytotoxicity of sTRAIL in tumor cells / 生物医学工程学杂志

ABSTRACT

Soluble tumor necrosis factor-related apoptosis-inducing ligand (sTRAIL) is potentially a novel anti-cancer drug due to its superior selective cytotoxicity in a wide variety of tumor cells. Zinc ion (Zn2+) insufficiency might be an important cause for weak cytotoxicity of sTRAIL prepared by gene engineering. In this paper, the sTRAIL protein is highly-expressed with insertion of the synthesized gene encoding sTRAIL into pQE30 plasmid. The polymerization and cytotoxicity in tumor cells of sTRAIL prepared in presence of different concentrations of Zinc ions were compared. It was found that the sTRAIL protein prepared in absence of Zinc ions mainly existed as monomer with weak cytotoxicity. However, in the presence of Zinc ions, sTRAIL formed homotrimer and showed strong cytotoxicity in tumor cells. These results demonstrate that Zinc ion is very important for cytotoxicity of sTRAIL. It is necessary for keeping stable activity of sTRAIL by addition of proper concentration of Zinc ion in the media.