Multifunctional Magneto‑Thermal Probe Enhances the Efficacy of Tumor Therapy as a Tumor Nanovaccine.

Magnetic hyperthermia therapy (MHT) is an emerging thermotherapeutic approach that has shown promising potential in cancer treatment. However, conventional MHT strategies exhibit limited capacity to activate anti-tumor immune responses, an essential factor for preventing cancer recurrence and metastasis. Therefore, improving the immunomodulatory efficacy of MHT remains a critical challenge. This study designed and developed a novel magneto-thermal probe, PSRNP, by conjugating anti-PD-L1 and RS09 peptides onto the surface of superparamagnetic iron oxide nanoparticles. The resulting PSRNP nanoprobes demonstrated excellent magneto-thermal conversion efficiency and favorable biocompatibility. In vivo analysis demonstrated that PSRNP-mediated MHT effectively remodels the tumor microenvironment. Meanwhile, PSRNP-mediated MHT showed superior immune activation effects, with a 5.14-fold increase in intratumoral CD86+ cells and a 3.30-fold increase in CD137+ cells compared with the Fe3O4-mediated MHT group. Furthermore, PSRNP-mediated MHT potentiated the therapeutic efficacy of tumor-infiltrating lymphocyte therapy and prevented tumor recurrence after surgical resection. The PSRNP probe represents an innovative platform for improving the immunotherapeutic performance of MHT in solid tumors. The findings of this study establish a theoretical and experimental foundation for advancing MHT as a synergistic cancer treatment strategy.