Core-shell TaOx@MnO nanoparticles as a nano-radiosensitizer for effective cancer radiotherapy.

Improving tumor oxygenation and concentrating X-ray radiation energy inside the tumor have received considerable attention in cancer radiotherapy. Herein, core-shell tantalum oxide@manganese dioxide (TaOx@MnO) nanostructures are prepared as an efficient radiosensitizer for enhancing radiotherapy (RT). In these nanostructures, the TaOx core serves as a RT sensitizer that efficiently concentrates X-ray radiation energy inside the tumor, while the MnO shell may trigger the decomposition of endogenous HO in the tumor microenvironment (TME) to generate oxygen and overcome hypoxia-associated radiation resistance. In vitro and in vivo experiments demonstrated that the synthesized TaOx@MnO-PEG nanostructures could accomplish an excellent synergistic radiotherapy sensitization effect. Furthermore, TaOx@MnO-PEG nanoparticles could also serve as promising agents for MR/CT dual-modal imaging. In brief, our study highlights a new type of multifunctional radiosensitizer agent to enhance radiotherapy treatment by means of simultaneously concentrating radiation energy inside tumors and overcoming tumor hypoxia, promising for applications in tumor radiotherapy.