Selenium-Platinum Coordination Compounds as Novel Anticancer Drugs: Selectively Killing Cancer Cells via a Reactive Oxygen Species (ROS)-Mediated Apoptosis Route

We report the preparation of selenium-containing platinum-based anticancer drug EG-Se/Pt. EG-Se/Pt was obtained from the coordination of selenium-containing molecules (EGSe) with cisplatin (CDDP). The structure of EG-Se/Pt was characterized by H-1 and Se-77 NMR spectroscopy, XPS, ESI-MS, and MALDI-TOF. In aqueous solution, EG-Se/Pt self-assembles to form spherical aggregates. EG-Se/Pt shows enhanced stability against dilution and high salt concentration compared with EG-Se. EG-Se/Pt induces cell apoptosis via reactive oxygen species (ROS), which leads to high selectivity between cancer cells and normal cells in cytotoxicity assays. More importantly, EG-Se/Pt effectively inhibits tumor growth in vivo in tumor-bearing mice. It is anticipated that tuning the ROS level through the assembly of selenium-containing molecules can be a general method to realize anticancer selectivity.