Mechanistic analysis of mitochondrial damage in CLL cells. (A) CLL cells were treated with or without 1.0 μM FP (6 hours), and mitochondrial and cytosolic fractions were isolated. (B) Mcl-1 levels in mitochondria relative to the control protein VDAC, and (C) Bcl-XL and cytochrome c in cytosolic fractions were analyzed by immunoblot. Data represent 3 independent experiments.