Apoptosis is the process of an intracellular death program leading to characteristic biochemical and morphological changes within a cell that consequently result in cell death[1]. A failure of cells to undergo apoptosis is a common feature of many cancers [2] thus investigation of apoptosis inducing mechanisms is of particular importance for cancer research and requires suitable detection methods.
A hallmark of late apoptosis is extensive genomic DNA fragmentation that generates a multitude of DNA double-strand breaks (DSBs) with accessible 3'-hydroxyl (3'-OH) groups. This characteristic forms the basis for a well-established apoptosis detection method: Terminal deoxynucleotidyl transferase dUTP Nick End Labeling (TUNEL) assay[3].