Nano-ROS-generating approaches to cancer dynamic therapy: Lessons from nanoparticles

Reactive oxygen species (ROS)-based dynamic cancer therapies are therapeutic modalities of endogenous/exogenous-responsive intratumoral ROS generation, including photodynamic therapy (PDT), sonodynamic therapy (SDT), radiation dynamic therapy (RDT), electrodynamic therapy (EDT), chemodynamic therapy (CDT) and microwave dynamic therapy (MDT). Dozens of pre-clinical and clinical evidences indicate that ROS-manipulated dynamic therapies effectively promote tumor regression. However, these dynamic therapeutic strategies face major obstacles, containing an insufficient supply of exogenous or endogenous stimulation, the potential toxicity of off-target initiators, and poor treatment outcome amongst deep solid tumors. With the rapid progress of biomedical nanotechnology, various cancer dynamic therapeutic nanoplatforms have been established to induce ROS production for treating a refractory tumor with high selectivity, safety, and non-invasiveness. This review outlines ROS-based fundamental mechanisms and the current clinical status of dynamic therapies. We summarize the recent advances of nanotechnology-assisted dynamic therapies in their superiority, single dynamic nano-applications against cancers, and synergistic effects of various dynamic nano-therapeutic modalities. Moreover, potential challenges and prospects have also been discussed. This review describes the advantages of ROS-based dynamic nano-therapies, aiming to release the inherent power of ROS for optimizing treatment effects.