Tumor-Derived Biomimetic Nanozyme With Immune Evasion Ability For Synergistically Enhanced Low Dose Radiotherapy

Abstract High doses of radiation can cause serious side effects and drug resistance, high-performance radiosensitizers are urgently needed. To overcome this issue, we developed a biomimetic nanozyme system (CF) by coating pyrite (FeS2) into tumor-derived exosomes for use in combination with low-dose RT. CF system give FeS2 with immune escape and homologous targeting abilities. After administration, CF with both glutathione oxidase (GSH) and peroxidase activities can significantly lower the content of GSH in tumor tissues and catalyze intracellular hydrogen peroxide (H2O2) to produce a large amount of ·OH for intracellular redox homeostasis disruption and mitochondria destruction, thus reducing RT resistance. Experiments in vivo and in vitro showed that combining CF with RT (2Gy) can provide a substantial suppression of tumor proliferation. To summarize, this is the first attempt to use exosomes bionic FeS2 nanozyme for realizing low-dose RT, which broaden the prospects of nanozymes.