pH-Sensitive Nanotheranostics for Dual-modality Imaging Guided Nanoenzyme Catalysis Therapy and Phototherapy
Triple-negative breast cancer shows resistance to conventional radiotherapy or chemotherapy, and no molecularly targeted therapy is available for this malignancy in clinical. In this work, a theranostic nanosystem with core-shell structure was synthesized through self-assembly of amphiphilic macromolecule, which could perform effective catalysis therapy and phototherapy. Herein, the superparamagnetic iron oxide (SPIO) nanocrystals and NIFI dyes IR780 were effectively loaded into the hydrophobic core of nanosystem, which enabled dual-modality magnetic resonance imaging and near-infrared fluorescence imaging; moreover, on hydrophilic crown, the neighboring carboxylic acid-based amide linkage showed charge conversion property in tumor acidic microenvironment and endowed the system targeted diagnosis and delivery. Through the light excitation, this theranostic system exerted synergistic anti-cancer activity through the nano-enzyme catalysis effect enhanced phototherapy in triple-negative 4T1 breast cancer model. Furthermore, there was no obvious side-effects. The results demonstrated a great potential of this theranostic nanosystem for cancer diagnosis and therapy.