Magnetic targeting systems for cancer therapy: bridging magnet design, advanced therapeutics, and clinical translation

Magnetic targeting systems integrate external magnetic fields with functionalized magnetic nanoparticles to enable precise intervention at tumor sites, addressing well-recognized limitations of conventional chemotherapy and immunotherapy, including insufficient intratumoral drug enrichment, systemic toxicity, and an immunosuppressive tumor microenvironment. This review systematically maps the evolution of this field from fundamental physical principles to intelligent closed-loop theranostics, and proposes a conceptual framework that positions magnetic targeting as a potential spatiotemporally precise mediator for tumor immune modulation. It examines the interplay between magnetic force and hemodynamic drag, the impact of nanoparticle physicochemical properties on in vivo fate, and compares engineering advances in static and dynamic magnetic systems. Therapeutic strategies – including magnetic hyperthermia combined with immune checkpoint inhibitors, magnetically targeted drug/nucleic acid delivery, cell therapy navigation, and magnetically driven ferroptosis – are analyzed for their immunoregulatory potential. The integration of real-time imaging guidance and artificial intelligence (AI)-driven optimization for theranostic closed-loop systems is also discussed, along with representative clinical trials and translational challenges. Despite persistent hurdles, magnetic targeting systems are evolving into enabling platforms for precise, individualized cancer therapy.