In Situ Fabrication of MS@MnO2 Hybrid as Nanozymes for Enhancing ROS‐Mediated Breast Cancer Therapy
Rreactive oxygen species (ROS) mediated anti-cancer therapy hold the advantages of tumor specificity, high curative effect, and low toxic side effects, which shows powerful potential for cancer treatment.However, hypoxia in tumor microenvironment (TME) and the low penetrability of photosensitizers limit their further application in clinic. Here, we present a composite structured core shell nanozymes (MS-ICG@MnO2@PEG) that consists of mesoporous silica nanoparticles (MS) core and MnO2 shell, loaded the photosensitizer indocyanine green (ICG), and then PEG coating as a photodynamic /chemodynamic therapeutic agent for ROS-mediated cancer treatment. One hand, MS-ICG@MnO2@PEG catalytic H2O2 to produce O2 enhanced photodynamic therapy (PDT), on the other hand, GSH consumed to trigger fentonlike reaction to generate *OH and then enhances chemodynamic therapy (CDT). At the cellular level, MS-ICG@MnO2@PEG embrance good biocompatibility and induces the production of ROS in 4T1 tumor cells. It disrupts the redox balance in tumor cells, affecting mitochondria function and specifically kills tumor cells. In vivo, MS-ICG@MnO2@PEG can selectively accumulate in tumor sites and inhibit tumor growth and metastasis in 4T1 tumor-bearing mice. Accordingly,this study shows that core-shell nanozymes can serve as an effective platform for ROS-mediated cancer treatment, enhancing the combination of PDT and CDT to treat breast cancer.