Tumor Microenvironment Activated Multifunctional Nanoparticles for Precisely Controlled Tumor Photothermal and Photodynamic Therapy

Therapeutic failures are always accompanied by surgery, chemotherapy, and radiotherapy when metastasis or therapeutic resistance is present in tumors. Thus, it is of critical importance to optimize the therapeutic strategy to realize a high curative effect along with the best safety for patients. To achieve this goal, therapeutic agents that can differentiate tumors from normal tissues and exert specific and controlled cancer treatments are highly desirable. In this work, we constructed a multifunctional nanoplatform specifically responsive to the acidic tumor microenvironment using polyaniline and indocyanine green (ICG) loaded hollow mesoporous silica nanoparticles. The proton-activable photothermal property facilitates the differentiation and targeted damage of tumor tissues. Then, these nanoparticles generated reactive oxygen species (ROS) and local heat simultaneously upon single laser irradiation to exert a high tumor ablation efficiency. Overall, the combination therapy of photothermal therapy (PTT) and photodynamic therapy (PDT) derived from the multifunctional nanoparticles has realized an elevated therapeutic efficacy compared to one single treatment mode. This unique nanomedicine represents a new design of tumor microenvironment-responsive therapeutical system for efficient cancer treatment, especially for the development of combined nanomedicine for further personalized cancer treatment.