Biomarkers for further studies on iron chelation and topoisomerase inhibition. Some of the biochemical causes and cellular consequences of iron-mediated ROS increase and DNA damage in cancer cells could be probed as illustrated in the diagram. The protein, lipid, and DNA mediators of cellular damage and the cellular outcomes of apoptosis, autophagy, and necrosis can be assayed using the endpoints that are shown adjacent to each step in the mechanism. A brief description of each of these assays is provided in the accompanying text. 8-oxoG, 7′,8′-dihydro-8-oxoguanine; AM, acetomethoxy derivative; DCFH-DA, 2′,7′-dichlorfluorescein-diacetate; HPLC, high performance liquid chromatography; ICE, immune complex with enzyme; LC3, microtubule-associated light chain protein; γ-H2AX, serine 139 phosphorylated histone H2A.