Apoptosis is a genetically controlled process for self-elimination of a cell, also known as "cell suicide".
Once apoptosis is initiated, the cell undergoes an organized break-down into small membrane-bound fragments called "apoptotic bodies", which can be rapidly ingested by macrophages. Apoptosis enables the safe removal of cells without releasing toxic intracellular substances or inducing an immune response. Apoptosis is therefore nature's "preferred" way to eliminate unneeded or dysfunctional cells.
There are multiple triggers of apoptosis. Some of them are (among others):
- Deprivation of growth factors
- DNA damage
- Immune reactions
- Ischemic injury
- Ionizing radiation
- Various toxins
Apoptosis also appears to be the major pathway by which tumor cells are eliminated in successful anti-cancer therapy with either chemotherapy or radiation.
Apoptosis may therefore become an important target for diagnosis, therapy and monitoring of the effect of therapy, across a wide range of medical disorders.