Abstract / Summary
Hydrogel-based drug delivery systems are redefining cancer therapy by enabling targeted, biocompatible, and stimuli-responsive treatment strategies. This review examines natural biopolymer hydrogels—such as chitosan, hyaluronic acid, alginate, gelatin, and collagen—and their role in precision oncology. These materials offer biodegradability, tunable properties, and low immunogenicity, supporting controlled drug release. We discuss gelation mechanisms, structural classifications from macrogels to nanogels, and the integration of stimuli-responsive features triggered by pH, temperature, light, and redox conditions within tumor microenvironments. Applications include chemotherapy, radiotherapy, immunotherapy, and phototherapy, using strategies such as passive targeting via the enhanced permeability and retention effect, active targeting via ligand functionalization, and stimuli-triggered release. Cancer-specific implementations in colorectal, gastric, liver, pancreatic, and breast tumors highlight hydrogel versatility. Key challenges include scalability, regulatory compliance, and tumor heterogeneity, while emerging innovations in smart hydrogels, nanotechnology, and personalized medicine offer promising solutions. This review underscores the potential of biopolymer-based hydrogels to advance cancer treatment toward safer, more effective, and patient-centered approaches.