A Review on Reactive Oxygen Species (ROS)-Inducing Nanoparticles Activated by Uni- or Multi-modal Dynamic Treatment for Oncotherapy

Cancer seriously threatens human health. As compared to normal tissue cells, tumor cells are generally more susceptible to oxidative stress and accumulate higher concentrations of reactive oxygen species (ROS). Accordingly, nanomaterials-based therapies that boost intracellular ROS generation have recently been effective in targeting and eliminating cancer cells by causing programmed death. This review presents a comprehensive analysis of ROS-generation induced by nanoparticles and critically examines the associated therapies which can be categorized as uni-modal (chemodynamic therapy, photodynamic therapy, sonodynamic therapy) and multi-modal (uni-modal therapy + chemotherapy, uni-modal therapy + uni-modal therapy) therapies. Comparison of the relative tumor volume ratio between the experimental and initial tumor volumes shows that multi-modal therapy significantly outperformed other treatments. However, the limitations of multi-modal therapy are in the difficulties of materials preparation and sophisticated operation protocols, thus limiting its applications in clinical practice. As an emerging treatment modality, cold atmospheric plasma (CAP) is a reliable source of ROS, light, and electromagnetic fields that can be used to implement multi-modal treatments in a simple setting. Therefore, the field of tumor precision medicine is expected to increasingly benefit from these promising and rapidly emerging multi-modal therapies based on ROS-generating nanomaterials and reactive media such as CAPs.