HMGB1 and cancer: It has previously been demonstrated that oncolytic poxvirus induced infected cancer cells into programmed necrosis and apoptosis with release of ATP, HMGB1 as well as immunogenic endoplasmic reticulum chaperone gp96, all danger signals to the innate immune system [36–39] and key signals for induction of antitumor immunity [2, 46, 47].