3D printing of high-strength bioscaffolds for the synergistic treatment of bone cancer

The challenges in bone tumor therapy are how to repair the large bone defects induced by surgery and kill all possible residual tumor cells. Compared to cancellous bone defect regeneration, cortical bone defect regeneration has a higher demand for bone substitute materials. To the best of our knowledge, there are currently few bifunctional biomaterials with an ultra-high strength for both tumor therapy and cortical bone regeneration. Here, we designed Fe-CaSiO3 composite scaffolds (30CS) via 3D printing technique. First, the 30CS composite scaffolds possessed a high compressive strength that provided sufficient mechanical support in bone cortical defects; second, synergistic photothermal and ROS therapies achieved an enhanced tumor therapeutic effect in vitro and in vivo. Finally, the presence of CaSiO3 in the composite scaffolds improved the degradation performance, stimulated the proliferation and differentiation of rBMSCs, and further promoted bone formation in vivo. Such 30CS scaffolds with a high compressive strength can function as versatile and efficient biomaterials for the future regeneration of cortical bone defects and the treatment of bone cancer. A method for three-dimensional printing of replacement bone that allows destruction of cancerous cells has been developed by scientists in China. Sometimes the only clinical approach to bone cancer is surgery that removes the affected tissue and replaces it with an artificial substitute. In the case of cortical bone, the dense tissue on a bone's surface, the engineered biomaterial needs to be of very high strength. Chengtie Wu from the Shanghai Institute of Ceramics, CAS and colleagues demonstrated an iron-calcium silicate composite scaffold that is simple to produce and has the strength necessary to support the human body. The team used composite scaffold because it can be heated by near infrared light to kill residual cancer cells, a technique known as photothermal therapy. Adding iron increased the strength of the scaffold. Fe-CaSiO3 composite scaffolds (30CS) were designed via 3D printing technique. Firstly, 30CS scaffolds possessed high compressive strength to provide sufficient mechanical support in bone cortical defects; Secondly, a synergistic therapy of photothermal and ROS achieved enhanced tumor therapeutic effect in vitro and in vivo; Thirdly, the presence of CaSiO3 in the composite scaffolds enforced the degradation performance and stimulated proliferation and differentiation of rBMSCs and further promoted bone forming in vivo. Such 30CS scaffolds with high compressive strength can function as versatile and efficient biomaterials for the future regeneration of cortical bone defects and therapy of bone cancer.