Near-Infrared-Mediated Self-Assembly of Graphene Quantum Dot-Based Nanoprobes to Silence Heat Shock Protein Expression for Mild Photothermal Therapy in Liposarcoma

Liposarcoma is one of the most common soft tissue sarcomas. It grows rapidly and is difficult to diagnose, until complications occur. Clinical surgery has become the only treatment strategy without any specific medicine available. The propensity for relapse urgently calls for the development of improved technologies. Nanotechnology-based technologies allow the early and accurate diagnosis and multifunctional treatment of liposarcoma, which has broad application prospects in clinical precision therapy. In this study, we describe a novel therapeutic strategy based on the near-infrared-mediated self-assembly of nanoprobes to effectively combat liposarcoma. We synthesized a novel type of graphene quantum dot (GQD), self-assembled with gadolinium ion (Gd3+) and IR820 dye by electrostatic adsorption, and then bonded the heat shock protein inhibitor 17-allylamino-17-demethoxy-geldanamycin (17-AAG) via electrostatic incorporation, resulting in innovative multifunctional IR820-triggerable GQD-Gd/IR820@AAG nanoprobes. This self-assembly system has been shown to be highly effective for in vivo and in vitro delivery and can be easily excreted after dissociation in vivo with greatly reduced biotoxicity. In vivo experiments demonstrated that the GQD-Gd/IR820@AAG nanoprobes induced downregulated heat shock protein expression in tumor cells, thereby reducing their heat tolerance threshold and effectively enhancing the effect of mild photothermal therapy. In addition, the nanoprobes displayed outstanding T1-magnetic resonance and near-infrared fluorescence imaging, owing to the presence of Gd3+ and IR820, respectively. The designed nanoprobes have considerable potential therapeutic value against liposarcomas.