Hydrogen Gas from Inflammation Treatment to Cancer Therapy.

Hydrogen (H) therapy is a highly promising strategy against several diseases due to its inherent biosafety. However, the current H treatment modalities rely predominantly on the systemic administration of the gas, resulting in poor targeting and utilization. Furthermore, although H has significant anti-tumor effects, the underlying mechanisms have not yet been elucidated. Due to their ultrasmall size, nanomaterials are highly suitable drug-delivery systems with a myriad of biomedical applications. Nanocarrier-mediated H delivery, as well as production of H by nanogenerators, can significantly improve targeted accumulation of the gas and accelerate the therapeutic effects. In addition, nanomaterials can be further modified to enhance passive or active accumulation at the target site. In this Perspective, we summarize the mechanism of H therapy and describe possibilities for combining H therapy with nanomaterials. We also discuss the current challenges of H therapy and provide some insights into this burgeoning field.