Treosulfan is an alkylating agent. Treosulfan inhibits several cancer cell lines, such as Panc-1, Miapaca-2 and Capan-2 cells, with IC50s of 3.6 μg/mL, 1.8 μg/mL and 2.1 μg/mL respectively, and shows nearly 100% cytotoxicity on these cell lines at 100 μg/mL. Treosulfan (0.1-100 μg/mL) in combination with LY 188011 exhibits enhanced activity against cancer cells. However, Treosulfan (1, 2.5, 5 μg/ml) combined with 5-FU (0.1, 0.25, 0.5 μg/ml) has antagonistic effect on Panc-1 cells at intermediate and high concentrations, and on Miapaca-2 cells at all doses. Treosulfan (800 µg/mL) dramatically reduces erythrocyte forward scatter, increases the percentage of annexin-V-binding cells, [Ca]i, and ROS. Removal of extracellular Ca abrogates the effect of Treosulfan on annexin-V-binding.