CPT-Se4, a seleno-derivative of Camptothecin (CPT), exhibits enhanced efficacy in cancer cell eradication and tumor suppression. It reduces the GSH/GSSG balance and total thiol content while increasing ROS concentrations in Hep G2 cells, leading to the induction of cancer cell apoptosis. Furthermore, CPT-Se4 demonstrates cytotoxicity towards a range of cell lines including HeLa, Hep G2, A549, and SMMC-7721, with IC50 values ranging from 2.54 to 6.4 μM [1].