Biofabricated Alginate Hydrogels to Study Prostate Tumoral Microenvironments In Vitro

Engineered three-dimensional (3D) in vitro models are essential for recapitulating the human tumor microenvironment (TME) and deciphering the complex cell-material interactions driving cancer progression. This study presents the development of a prostate-specific bioprinted model designed to mimic both the biomechanical (stiffness) and biochemical (laminin-enriched) traits of the prostate cancer (PCa) extracellular matrix (ECM). We synthesized functionalized alginate hydrogels modified with laminin-mimetic peptides (IKVAV, AG73) and tuned their mechanical properties (2-20 kPa) to match the transition from healthy tissue to advanced/metastatic disease. Functionalized alginate hydrogel precursors were compatible with extrusion-based bioprinting and used to replicate TME heterogeneity by 3D bioprinting in vitro models containing PC-3 cells and cancer-associated fibroblasts (CAFs). PC-3 cells cocultured with cancer-associated fibroblasts (CAFs) within these hydrogels supported high cell viability and proliferation. Notably, phenotypic analysis revealed that stiffer, laminin-enriched matrices significantly upregulated the expression of CD44 and the epithelial-to-mesenchymal transition (EMT) marker vimentin in PC-3 cells. Interestingly, these matrix-driven effects were dominant, independent of the CAF presence within the observed window. This work establishes a robust, scalable biofabrication strategy for generating TME-mimetic models, offering a valuable tool for future studies in screening TME-targeting therapies and investigating the mechanobiology of PCa progression.