Autophagy Blockage Enhancing Photothermal and Chemodynamic Synergistic Therapy Based on HCQ/CuS Nanoplatform.

As an intracellular protective mechanism, autophagy has the potential to significantly impair the therapeutic effects of photothermal therapy (PTT) and chemodynamic therapy (CDT), which helps cancer cells survive under harsh conditions, such as high temperature and reactive oxygen species (ROS). In this study, an autophagy blockage enhanced PTT and CDT synergistic therapy nanoplatform is constructed by loading hydroxychloroquine (HCQ) with autophagy inhibitory effect into hollow copper sulfide (HCuS). Specifically, HCuS produces toxic ROS through Fenton-like reaction in the tumor microenvironment (TME). At the same time, PTT-mediated temperature elevation of the tumor region accelerates the Fenton-like reaction and ROS production, enhancing the therapeutic effect of CDT. Furthermore, the internal autophagy inhibitor HCQ significantly blocks the fusion of autophagosomes and lysosomes by deacidifying lysosomes, cutting off the self-protection mechanism of cancer cells, and amplifying the combined treatment of PTT and CDT. Both in vitro and in vivo results demonstrate that the combination of photothermal-enhanced chemodynamic therapy with inhibition of autophagy provides new insights into designing multifunctional therapeutic nanoagents.