BCL2 and B-cell chronic lymphocytic leukemia: BAX/BAK oligomerization causes mitochondrial outer membrane permeabilization, resulting in cytochrome c release and apoptosis.9, 10 Chronic lymphocytic leukemia (CLL) cells rely on increased expression of anti-apoptotic BCL-2 proteins; strategies to restore apoptosis by antagonizing them have led to development of BH3 mimetics as therapeutic agents that have a robust clinical response with reduced toxicity.9, 11