MSOT/CT/MR imaging-guided and hypoxia-maneuvered oxygen self-supply radiotherapy based on one-pot MnO2-mSiO2@Au nanoparticles

Abstract

Radiotherapy (RT) is one of the most widely applied treatments for cancer therapy in clinics. Herein, we constructed innovative multifunctional nanotheranostic MnO₂-mSiO₂@Au-HA nanoparticles (MAHNPs) based on one-pot MnO₂-mSiO₂ nanohybrids (MNHs) and gold nanoparticles (AuNPs) for multispectral optoacoustic tomography (MSOT)/computed tomography (CT) and magnetic resonance (MR) imaging-guided hypoxia-maneuvered radiotherapy. The MNHs were prepared via a facile one-pot approach, which avoided the leakage of MnO₂ nanoparticles and increased the synthetic efficiency. The Mn²⁺ ions triggered the breakdown of endogenous H₂O₂ to generate O₂ to convert the hypoxic tumor micro-environment (TME), thus enhancing radiotherapy by self-supply oxygen. In addition, hyaluronic acid (HA) was employed to modify the surface of the MnO₂-mSiO₂@Au nanoparticles to improve their biocompatibility and cellular uptake. The well-designed nanoparticles could perform remarkable photothermal therapy (PTT) and hypoxia-maneuvered radiotherapy (RT) simultaneously and MSOT/CT/MR imaging. The in vivo studies showed that the MAHNPs achieved almost total suppression of tumor growth without observable recurrence, which raises new possibilities for clinical nanotheranostics with multimodal diagnostic and therapeutic coalescent design.