B-cell lymphoma protein 2 family proteins (BCL-2 family)

The BCL-2 family is a group of evolutionarily conserved proteins that are central regulators of apoptosis, particularly the intrinsic (mitochondrial) pathway. This family includes both anti-apoptotic members such as BCL-2, BCL-xL, and Mcl-1, as well as pro-apoptotic members like Bax and Bak. The balance between these opposing factions determines cell fate in response to stress or developmental cues. Dysregulation—especially overexpression—of anti-apoptotic members like BCL‑2 is implicated in various cancers including follicular lymphoma due to chromosomal translocations such as t(14;18). Overexpression leads to resistance against programmed cell death—a hallmark of cancer progression. Therapeutic targeting with small-molecule inhibitors ("BH3 mimetics") has shown promise in hematological malignancies by restoring apoptotic sensitivity. Mcl‑1 is essential for survival across multiple immune cell types including T lymphocytes at various developmental stages.

Other names

BCL2 familyBcl-2/Bcl-xL/Mcl-1BCL-2 proteinsApoptosis regulators

Inhibition of anti-apoptotic proteins, activation of pro-apoptotic proteins, promotion of cytochrome c release from mitochondria