Impact of scaffold material choice on osteosarcoma phenotype and drug responses in 3D.

Biomaterials-based 3D models have emerged as new cancer research tools for studying osteosarcoma (OS). However, the impact of scaffold material choice on OS phenotype and drug responses in 3D remains largely unknown, as previous studies used different biomaterials as scaffolds without direct comparison. In this study, we systematically compared four biomaterials: Gelatin methacrylate (GelMA), Gelatin microribbons (Gel µRB), Collagen I hydrogel (Col1), and Poly(DL-lactide-co-glycolide) (PLGA). All have previously been applied for either 3D OS culture or bone tissue engineering. To mimic the mineral component of bone, hydroxyapatite mineral nanoparticles (HAnp) were incorporated into all scaffolds. We assessed key clinically relevant OS phenotypes including cell proliferation, extracellular matrix (ECM) deposition, and responses to multiple chemotherapeutic agents. Our results demonstrate that scaffold material significantly influences OS phenotype and drug resistance. Notably, PLGA results in the lowest cell proliferation, GelMA promotes drug resistance and tumor ECM deposition, and Gel µRB better mimics OS signaling of orthotopic tumor xenografts in vivo. The findings from this comparative study underscore the impact of scaffold choice on OS phenotype and drug response. It also provides valuable insights for guiding the selection of appropriate scaffold materials to better mimic the desirable OS phenotype to advance OS therapeutic discovery. STATEMENT OF SIGNIFICANCE: Osteosarcoma (OS), a highly aggressive bone cancer, has seen a stagnant survival rate for over three decades. This study addresses a critical knowledge gap by comparing four widely used bone tissue engineering scaffolds for 3D OS culture. Unlike previous studies, this work provides a comprehensive analysis of how scaffold choice influences OS proliferation, signaling, extracellular matrix deposition, and drug resistance. These findings underscore the critical role of biomaterials choice in modulating OS behavior and will guide the choice of 3D scaffolds for more effective OS disease modeling and improving therapeutic discovery.