Advanced nanomaterials targeting hypoxia to enhance radiotherapy

Hypoxia within solid tumors is often responsible for the failure of radiotherapy. The development of hypoxia-targeting nanomaterials – aimed at enhancing the effect of radiotherapy by electrical or heat effects and at modulating hypoxia in the tumor microenvironment – is a promising strategy to address this issue. We provide an overview of recently developed advanced materials that potentiate radiotherapy. First, we summarize novel materials for oxygen delivery or production to modify the tumor microenvironment, thus improving the effects of ionizing radiation. Second, we present new approaches for the design of high-Z element–based multifunctional nanoplatforms to enhance radiotherapy. Third, novel drug delivery systems for hypoxic regions and hypoxia-inducible factor-1–targeted therapies are discussed. Fourth, we establish the effectiveness of X-ray-or near-infrared–responsive nanoparticles for selectively triggering therapeutic effects under hypoxic conditions. Finally, this review emphasizes the importance of research in the field of nanomedicine focused on tumor hypoxia to improve clinical outcomes.