Ultrasound-Activated Multifunctional Bioactive Calcium Phosphate Composites for Enhanced Osteosarcoma Treatment

Bone defects caused by surgical interventions and the challenges of tumor recurrence and metastasis due to residual cancer cells significantly complicate the treatment of osteosarcoma (OS). To address these complex clinical challenges, we propose an innovative therapeutic strategy that centers on an ultrasound-activated multifunctional bioactive calcium phosphate (BioCaP) composite. A modified curcumin (mcur)-mediated wet biomimetic mineralization process was used to develop an anticancer-drug-integrated multifunctional BioCaP (mcur@BioCaP), exploring its potential biological effects for OS treatment activated by ultrasound (US). The mcur@BioCaP demonstrates a drug dose-dependent, tailorable alteration in its micro/nanostructure. The US stimulus significantly enhanced this composite to generate reactive oxygen species (ROS) in cancer cells. The results show that the OS cell viability of the mcur@BioCaP with US is 62.2% ± 6.3%, the migration distance is 63.9% ± 6.6%, and the invaded OS cell number is only 57.0 ± 3.7 OS cells per version, which were all significantly lower than US or mcur@BioCaP alone, suggesting that the anticancer, anti-migratory and anti-invasive effects of mcur@BioCaP on OS 143B cells were amplified by ultrasonic stimulation. This amplification can be attributed to the US-activated ROS production from the drug molecules, which regulates the wet biomimetic mineralization of the multifunctional composite. Furthermore, mcur@BioCaP with US increased calcium nodule formation by 1.8-fold, which was significantly higher than mcur@BioCaP or US group, indicating its potential in promoting bone regeneration. The anticancer and osteogenic potentials of mcur@BioCaP were found to be consistent with the mcur concentration in the multifunctional composite. Our research provides a novel therapeutic approach that leverages a multifunctional biomimetic mineral and ultrasonic activation, highlighting its potential applications in OS therapy.