Cell lysis, SDS‐PAGE and immunoblot analysis were performed as described previously.8 (link) Membranes were incubated with antibodies against the following proteins: BIG3 (diluted 1:250),6 (link) PHB2 (Abcam #ab71970, diluted 1:1000), β‐actin (clone AC‐15, Sigma‐Aldrich #A1978, diluted 1:5000), PARP (CST #9542, diluted 1:500), and apoptosis‐inducing factor (AIF) (clone E‐1, Santa Cruz Biotechnology #sc‐13116, diluted 1:200). After incubation with HRP‐conjugated secondary antibodies (anti‐mouse IgG‐HRP, diluted 1:5000; anti‐rat IgG‐HRP, diluted 1:5000; anti‐rabbit IgG‐HRP, diluted 1:1000 [Santa Cruz Biotechnology]) for 1 hour, the blots were developed with an enhanced chemiluminescence system (GE Healthcare) and scanned using an Image Reader LAS‐3000 Mini (Fujifilm).