CuET is a metabolite of Disulfiram and acts as an inducer of copper-induced cell death (cuproptosis) and ferroptosis, exhibiting antitumor activity. It can directly interact with polyunsaturated phospholipids to generate free radicals, leading to lipid peroxidation. Through excessive copper accumulation, CuET induces cuproptosis, resulting in the aggregation of fatty acylated proteins and the loss of iron-sulfur cluster proteins. It also triggers ferroptosis via a copper-activated, radical-dependent pathway, with a lower dependence on iron accumulation, while altering lipid composition to increase cell sensitivity to oxidative damage. CuET elevates reactive oxygen species (ROS) and MDA levels within cancer cells. Both in vitro and in vivo, CuET demonstrates antitumor effects against non-small cell lung cancer and can be utilized in cancer-related research, such as studies on non-small cell lung cancer.