Primary induction of photo-oxidative (phox)-ER stress in cancer cells evoked immunogenic apoptosis (IA) associated with pre-apoptotic emission of calreticulin and ATP, and protective antitumor immunity. This IA subroutine involved "core" functions (e.g., PERK/PI3K-based modulation of secretory trafficking) rather than "private" ones (caspase-8 and eIF2α-phosphorylation) engaged by other IA inducers.