Gallic acid grafting modulates the oxidative potential of ferrimagnetic bioactive glass-ceramic SC-45

Bifunctional mesoporous glasses for bone tissue engineering: Biological effects of doping with cerium and polyphenols in 2D and 3D in vitro models

This study evaluates the cytocompatibility of cerium-doped mesoporous bioactive glasses (Ce-MBGs) loaded with polyphenols (Ce-MBGs-Poly) for possible application in bone tissue engineering after tumour resection. We tested MBGs powders and pellets on 2D and 3D in vitro models using human bone marrow-derived mesenchymal stem cells (hMSCs), osteosarcoma cells (U2OS), and endothelial cells (EA.hy926). Promisingly, at a low concentration in culture medium, Poly-loaded MBGs powders containing 1.2 mol% of cerium inhibited U2OS metabolic activity, preserved hMSCs viability, and had no adverse effects on EA.hy926 migration. Moreover, the study discussed the possible interaction between cerium and Poly, influencing anti-cancer effects. In summary, this research provides insights into the complex interactions between Ce-MBGs, Poly, and various cell types in distinct 2D and 3D in vitro models, highlighting the potential of loaded Ce-MBGs for post-resection bone tissue engineering with a balance between pro-regenerative and anti-tumorigenic activities.

Bioactive Glasses Modulate Anticancer Activity and Other Polyphenol-Related Properties of Polyphenol-Loaded PCL/Bioactive Glass Composites

In this work, bioactive glass (BG) particles obtained by three different methods (melt-quenching, sol-gel, and sol-gel-EISA) were used as modifiers of polyphenol-loaded PCL-based composites. The composites were loaded with polyphenolic compounds (PPh) extracted from sage (Salvia officinalis L.). It was hypothesized that BG particles, due to their different textural properties (porosity, surface area) and surface chemistry (content of silanol groups), would act as an agent to control the release of polyphenols from PCL/BG composite films and other significant properties associated with and affected by the presence of PPh. The polyphenols improved the hydrophilicity, apatite-forming ability, and mechanical properties of the composites and provided antioxidant and anticancer activity. As the BG particles had different polyphenol-binding capacities, they modulated the kinetics of polyphenol release from the composites and the aforementioned properties to a great extent. Importantly, the PPh-loaded materials exhibited multifaceted and selective anticancer activity, including ROS-mediated cell cycle arrest and apoptosis of osteosarcoma (OS) cells (Saos-2) via Cdk2-, GADD45G-, and caspase-3/7-dependent pathways. The materials showed a cytotoxic and antiproliferative effect on cancerous osteoblasts but not on normal human osteoblasts. These results suggest that the composites have great potential as biomaterials for treating bone defects, particularly following surgical removal of OS tumors.

Bioactive Glasses as Carriers of Cancer-Targeted Drugs: Challenges and Opportunities in Bone Cancer Treatment

The treatment of bone cancer involves tumor resection followed by bone reconstruction of the defect caused by the tumor using biomaterials. Additionally, post-surgery protocols cover chemotherapy, radiotherapy, or drug administration, which are employed as adjuvant treatments to prevent tumor recurrence. In this work, we reviewed new strategies for bone cancer treatment based on bioactive glasses as carriers of cancer-targeted and other drugs that are intended for bone regeneration in conjunction with adjuvant treatments. Drugs used in combination with bioactive glasses can be classified into cancer-target, osteoclast-target, and new therapies (such as gene delivery and bioinorganic). Microparticulated, nanoparticulated, or mesoporous bioactive glasses have been used as drug-delivery systems. Additionally, surface modification through functionalization or the production of composites based on polymers and hydrogels has been employed to improve drug-release kinetics. Overall, although different drugs and drug delivery systems have been developed, there is still room for new studies involving kinase inhibitors or antibody-conjugated drugs, as these drugs have been poorly explored in combination with bioactive glasses.