ATF4 and neuroblastoma: While these reports have shown that loss of BOK affects a specific branch of UPR signaling, such as IRE1- (Echeverry et al., 2013) or PERK-eIF2α-ATF4-signaling (Carpio et al., 2015), our data indicate that BOK deficiency influences indeed all three UPR-signaling branches in the neuroblastoma-derived cell lines.