Metallo-alginate hydrogel can potentiate microwave tumor ablation for synergistic cancer treatment

Microwave ablation (MWA) as a local tumor ablation strategy suffers from posttreatment tumor recurrence. Development of adjuvant biomaterials to potentiate MWA is therefore of practical significance. Here, the high concentration of Ca-2+ fixed by alginate as Ca2+-surplus alginate hydrogel shows enhanced heating efficiency and restricted heating zone under microwave exposure. The high concentration of extracellular Ca2+ synergizes with mild hyperthermia to induce immunogenic cell death by disrupting intracellular Ca2+ homeostasis. Resultantly, Ca2+-surplus alginate hydrogel plus MWA can ablate different tumors on both mice and rabbits at reduced operation powers. This treatment can also elicit antitumor immunity, especially if synergized with Mn2+, an activator of the stimulation of interferon genes pathway, to suppress the growth of both untreated distant tumors and rechallenged tumors. This work highlights that in situ-formed metallo-alginate hydrogel could act as microwave-susceptible and immunostimulatory biomaterial to reinforce the MWA therapy, promising for clinical translation.

Automated summary

The study demonstrates that Ca2+-surplus alginate hydrogel can enhance microwave ablation (MWA) therapy by increasing heating efficiency and inducing immunogenic cell death. Synergizing with Mn2+, it can also strengthen antitumor immunity and suppress tumor growth. This finding is of great significance for clinical translation.