Cis-diamminedichloroplatinum (II) cisplatin (CDDP) is an organometallic compound frequently used in anti-cancer therapy, in particular ovarian, testicular, and head and neck tumors. We found cisplatin was effective against human promyelocytic leukemia cell line HL-60, inhibiting cell cycle progression and inducing time- and concentration- dependent cell death. Presence of nuclear fragmentation, caspase-3 cleavage and annexin V positivity suggests cell death occurred by apoptosis, although DNA internucleosomal fragmentation was not detected. In addition, analysis of malondialdehyde (MDA) production and protein carbonylation indicated that cisplatin increased lipid peroxidation and oxidation of cell proteins. This occurrence was prevented by antioxidants such as N-acetylcysteine (N-aC) and glutathione (GSH), which, consistently, were also able to prevent CDDP-induced cell death. Collectively, these findings indicate that, besides growth inhibition, an increase of oxygen radicals and lipid degradation can account for a significant part of CDDP-induced apoptosis.