A Multi-Functional Cascade Nanoreactor for Remodeling Tumor Microenvironment to Realize Mitochondria Dysfunction via ROS/Zn2+ Ions Overload.

Abstract

Combining chemo/photodynamic therapy (CDT/PDT) to generate highly harmful reactive oxygen species and cause mitochondria dysfunction is considered a potential strategy to improve the efficiency of anticancer treatment. However, within tumor, the relatively deficient concentration of H2O2, hypoxic microenvironment, and overexpressed reduced glutathione (GSH)seriously suppress the efficacy of dynamic therapy. Herein, a multi-functional cascade nanoreactor, bovine serum albumin modified ZnO2@CeO2-ICG, is reported for remodeling tumor microenvironment (TME) to boost dynamic therapy and realize mitochondria dysfunction via reactive oxygen species (ROS) storm/Zn2+ ions overload. Within TME, ZnO2 decomposed into exogenous H2O2 and Zn2+ ion. The dual enzyme-like CeO2 catalyzes the increased H2O2 into ·OH and oxygen molecules respectively, and then the oxygen molecules are translated into 1O2 by indocyanine green (ICG) under 808 nm light irradiation to boost PDT. The effective consumption of GSH through the reduction of Ce(IV) ions not only regenerates Ce(III) ions to enhance the efficiency of CDT but also efficaciously alleviates the elimination of ROS generated by dynamic therapy to further improve dynamic therapeutic efficiency. So the improved ROS level under remodeling TME and Zn2+ ions acutely lead to mitochondria dysfunction to boost the efficiency of antitumor treatment. Thus, developing functional nanoreactors that enable remodeling TME provides a potential strategy to enhance the efficiency of dynamic therapy.