The Bcl-2 protein family consists of pro-apoptotic and anti-apoptotic members. Anti-apoptotic proteins, such as Bcl-2, Bcl-xL, and Mcl-1, promote cell survival by inhibiting apoptosis, whereas pro-apoptotic proteins like Bax and Bak promote cell death. The balance between these proteins determines the fate of a cell. In many cancers, overexpression of anti-apoptotic proteins leads to resistance to cell death, contributing to tumor survival and progression.
