The in situ lactate oxidase (LOx) catalysis is highly efficient in reducing oxygen to H2O2 due to the abundant lactate substrate in the hypoxia tumor microenvironment. Dynamic therapy, including chemodynamic therapy (CDT), photodynamic therapy (PDT), and enzyme dynamic therapy (EDT), could generate reactive oxygen species (ROS) including ·OH and 1O2 through the disproportionate or cascade biocatalytic reaction of H2O2 in the tumor region. Here, we demonstrate a ROS-based tumor therapy by integrating LOx and the antiglycolytic drug Mito-LND into Fe3O4/g-C3N4 nanoparticles coated with CaCO3 (denoted as FGLMC). The LOx can catalyze endogenous lactate to produce H2O2, which decomposes cascades into ·OH and 1O2 through Fenton reaction-induced CDT and photo-triggered PDT. Meanwhile, the released Mito-LND contributes to metabolic therapy by cutting off the source of lactate and increasing ROS generation in mitochondria for further improvement in CDT and PDT. The results showed that the FGLMC nanoplatform can multifacetedly elevate ROS generation and cause fatal damage to cancer cells, leading to effective cancer suppression. This multidirectional ROS regulation strategy has therapeutic potential for different types of tumors.
Keywords: CDT; PDT; ROS; cancer; lactate oxidase.