Cell treatment with gallium(III)complexes promoted several cell death triggering signals (accumulationof p27, PCNA, PARP fragments, activation of the caspase cascade, andinhibition of the mevalonate pathway) and induced changes in cellredox homeostasis (decreased levels of GSH/GPX4 and NADP(H), increasedreactive oxygen species (ROS) and 4-hydroxynonenal (HNE), mitochondrialdamage, and increased activity of CPR and CcO), identifying ferroptosisas the mechanism responsible for cancer cell death. This evidence concerns the gene GPX4 and cancer.