Magnetic Nanostructures as Emerging Therapeutic Tools to Boost Anti-Tumour Immunity

Abstract

Cancer immunotherapy has shown remarkable results in various cancer types through a range of immunotherapeutic approaches, including chimeric antigen receptor-T cell (CAR-T) therapy, immune checkpoint blockade (ICB), and therapeutic vaccines. Despite the enormous potential of cancer immunotherapy, its application in various clinical settings has been limited by immune evasion and immune suppressive mechanisms occurring locally or systemically, low durable response rates, and severe side effects. In the last decades, the rapid advancement of nanotechnology has been aiming at the development of novel synthetic nanocarriers enabling precise and enhanced delivery of immunotherapeutics, while improving drug stability and effectiveness. Magnetic nanostructured formulations are particularly intriguing because of their easy surface functionalization, low cost, and robust manufacturing procedures, together with their suitability for the implementation of magnetically-guided and heat-based therapeutic strategies. Here, we summarize and discuss the unique features of magnetic-based nanostructures, which can be opportunely designed to potentiate classic immunotherapies, such as therapeutic vaccines, ICB, adoptive cell therapy (ACT), and in situ vaccination. Finally, we focus on how multifunctional magnetic delivery systems can facilitate the anti-tumour therapies relying on multiple immunotherapies and/or other therapeutic modalities. Combinatorial magnetic-based therapies are indeed offering the possibility to overcome current challenges in cancer immunotherapy.

Recent advances in mechanical force-responsive drug delivery systems

“…Most magnetically responsive DDSs used magnetically guided targeting or magnetically generated heat for therapy or controllable drug release. 117 Herein, a DDS with magnetic force was chosen as the main factor to control its drug release behavior, although magnetic hyperthermia could also be a useful approach. 118 In the following section, recent reports on magnetic response DDSs from the perspective of the external magnetic field and the magnet guidance system of the magnetic implant will be discussed.…”

Nano-Based Drug Delivery and Targeting to Overcome Drug Resistance of Ovarian Cancers

“…In PBM techniques, heat-absorbent zirconium oxide planetary milling balls and jars are used to mill the particles that rotate around a shared axis of the chamber wheel. In general, for efficient delivery to the target tumor cells, a round shape and a size <100 nm for the NPs are more favorable [ 170 ]. By controlling the size and number of zirconium oxide balls, milling cycles, grinding speed, centrifugal force, and planetary jar velocity, PBM can engineer the NP size range from 5 nm to 60 μm [ 151 , 169 , 171 ] ( Figure 2 ).…”

Advanced Magnetic Resonance Imaging (MRI) Techniques: Technical Principles and Applications in Nanomedicine

“…Superparamagnetic nanomaterials have excellent magnetic properties because they combine the high magnetization of bulk magnetite with the paramagnetic nature of Fe ions. Outside of a magnetic field, these nanomaterials have no magnetic moments [ 49 ]. In contrast, if a magnetic field is applied, the magnetic moments align with the field and behave like a paramagnet, but with a higher magnetic susceptibility [ 50 , 51 ] ( Figure 1 ).…”