Mitotic catastrophe refers to a mechanism of delayed mitosis-linked cell death, a sequence of events resulting from premature or inappropriate entry of cells into mitosis that can be caused by chemical or physical stresses. Mitotic catastrophe is unrelated to programmed cell death or apoptosis and is observed in cells lacking functional apoptotic pathways. It is has been observed following delayed DNA damage induced by ionizing radiation. It can also be triggered by agents influencing the stability of microtubule spindles, various anticancer drugs and mitotic failure caused by defective cell cycle checkpoints. Mitotic catastrophe is the primary mechanism underlying reproductive cell death in cancer cells treated with ionizing radiation.
Not all cells die immediately following abnormal mitosis caused by mitotic catastrophe, but many do. Cells that do not immediately die are likely to create aneuploid cells following subsequent attempts at cell division posing a risk of oncogenesis (i.e. potentially leading to cancer). A very small fraction of these aneuploid cells produced by mitotic catastrophe might later reduce DNA ploidy by reductive division involving meiotic cell division pathways.