CS47 is a reversible inhibitor of thioredoxin reductase 1 (TrxR1). It activates stress-responsive glutathione (GSH) and iron regulatory pathways, leading to GSH depletion. This results in reactive oxygen species (ROS) accumulation, promoting HO-1 overexpression and causing intracellular iron overload, which ultimately induces ferroptosis in lung cancer not dependent on the KRAS gene. CS47 exhibits anticancer activity with low cytotoxicity to normal lung fibroblasts.