Nanohydroxyapatite-Stabilized Pickering-Emulsion-Incorporated Hydrogel Prevents Postoperative Osteosarcoma Recurrence and Promotes Bone Repair

Osteosarcoma (OS) is a highly aggressive malignancy. Current therapies offer limited efficacy, necessitating innovative strategies. This study introduces a novel injectable hydrogel integrated with nanohydroxyapatite (nHAP)-stabilized Pickering emulsions for the local delivery of receptor activator of nuclear factor κB ligand inhibitor. We assessed the system's efficacy through cell viability, apoptosis, and migration assays in osteosarcoma cells and evaluated tumor suppression and bone regeneration in a critical-sized skull defect model in mice. Our results indicate that the system significantly induced apoptosis and inhibited migration in osteosarcoma cells. In an animal model, the hydrogel system demonstrated an inhibitory effect on tumor growth, reducing the tumor volume. Furthermore, new bone formation was observed at the skull defect site, suggesting the system's potential for both antitumor activity and the promotion of bone repair. This integrated system offers enhanced antitumor efficacy and bone regeneration capabilities, thus improving OS treatment outcomes.