Antioxidant enzymes (AOEs), including superoxide dismutase isoenzymes (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) along with glutathione reductase (GR), reduced glutathione (GSH) and glutathione transferase (GST), are thought to be necessary for life processes in all oxygen-metabolizing cells by removing reactive oxygen species (ROS). The biological significance of AOEs in transformed cells is still unclear, but their capacity to survive may be affected by changes in cellular processes such as proliferation, invasiveness, migration, apoptosis and drug resistance. This review summarizes the significance of antioxidant enzymes in cancer cell progression mainly in an in vitro context.