Bridging biomaterials and immunotherapy: hydrogel strategies for next-generation CAR-T cell treatment.

Breast cancer remains a leading cause of cancer-associated mortality worldwide, with an increasing incidence among younger women, particularly in developing regions and immigrant populations. Although advances in diagnostics and targeted therapies have improved patient outcomes, the search for more effective and less toxic treatments continues. Chimeric antigen receptor (CAR) T-cell therapy has transformed cancer immunotherapy by harnessing the body's own immune system to fight malignancy, yet its full potential in solid tumors is still being realized. Meanwhile, hydrogel-based biomaterials have emerged as versatile platforms capable of local immune modulation, sustained cytokine delivery, and enhanced T-cell activation within the tumor microenvironment. By bridging materials science with tumor immunology, this evolving field offers a new perspective on how to direct immune activity precisely where it is needed. Combining hydrogel technology with CAR-T cell therapy represents a promising strategy to strengthen antitumor responses and improve treatment precision and safety.