A chemo-free thermo-sensitive necroptosis-inducing perfusate to enable potent hyperthermic intraperitoneal immunotherapy.

Hyperthermic intraperitoneal chemotherapy (HIPEC) is widely performed for treating peritoneal malignancies, yet its clinical application remains limited by insufficient efficacies and risks in chemotherapy-associated side effects. This study demonstrates that mild hyperthermia enhances cancer cell sensitivity to hydrogen peroxide (H2O2) and Ca2+ exposure while sparing normal cells at both elevated and physiological temperatures. Mechanistically, mild hyperthermia promotes H2O2 cellular entry, synergistically activating calcium channels in the plasma membrane and endoplasmic reticulum to induce Ca2+-overload-dependent cancer cell necroptosis. Using H2O2 and Ca2+ solution as a thermo-sensitive necroptosis-inducing perfusate (TNIP), peritoneal perfusion at 43°C demonstrates stronger suppressive effects on the growth of multiple peritoneal tumors in mice compared to conventional HIPEC using various chemotherapeutics. TNIP-mediated hyperthermic intraperitoneal treatment also elicits robust antitumor immunity in syngeneic murine models, with enhanced therapeutic efficacy when combined with postoperative immune checkpoint blockade therapy. The superior immune activation capacities of this strategy are further validated in patient-derived organoids. This work establishes a chemo-free, thermo-activated immunogenic perfusion strategy to selectively trigger cancer cell necroptosis, demonstrating a translatable hyperthermic intraperitoneal immunotherapy with improved therapeutic efficacy and safety.