Hybrid Systems of Gels and Nanoparticles for Cancer Therapy: Advances in Multifunctional Therapeutic Platforms.

Cancer is a global health concern. Various therapeutic approaches, including chemotherapy, photodynamic therapy, and immunotherapy, have been developed for cancer treatment. Silica nanoparticles, quantum dots, and metal-organic framework (MOF)-based nanomedicines have gained interest in cancer therapy because of their selective accumulation in tumors via the enhanced permeability and retention (EPR) effect. However, bare nanoparticles face challenges including poor biocompatibility, low stability, limited drug-loading capacity, and rapid clearance by the reticuloendothelial system (RES). Gels with unique three-dimensional network structures formed through various interactions such as covalent and hydrogen bonds are emerging as promising materials for addressing these challenges. Gel hybridization enhances biocompatibility, facilitates controlled drug release, and confers cancer-targeting abilities to nanoparticles. This review discusses gel-nanoparticle hybrid systems for cancer treatment developed in the past five years and analyzes the roles of gels in these systems.