BCL2 belongs to the Bcl-2 family. It suppresses apoptosis in a variety of cell systems including factor-dependent lymphohematopoietic and neural cells. BCL2 regulates cell death by controlling the mitochondrial membrane permeability. It appears to function in a feedback loop system with caspases. BCL2 inhibits caspase activity either by preventing the release of cytochrome c from the mitochondria and/or by binding to the apoptosis-activating factor (APAF-1).