Innovations in the Delivery of Bioactive Compounds for Cancer Prevention and Therapy: Advances, Challenges, and...

Naturally occurring bioactive compounds represent a promising option for cancer prevention and therapy due to their ability to modulate apoptosis, angiogenesis, inflammation, oxidative stress, and cell signaling. However, their clinical impact is limited by low bioavailability, chemical instability, rapid metabolism, and poor tumor microenvironment accumulation. Innovative delivery platforms, including lipid and polymeric nanoparticles, liposomes, micelles, nanoemulsions, hydrogels, and stimulus-responsive systems, have been developed to improve stability, absorption, tumor specificity, and therapeutic efficacy. This review integrates molecular mechanisms, preclinical and clinical evidence, and recent technological advances, highlighting both potential and limitations. Although several compounds show encouraging results in cell and animal models, only a small number have progressed to early clinical trials, where outcomes remain heterogeneous and often fail to replicate preclinical magnitudes. Regulatory barriers, a lack of formulation standardization, and the absence of predictive biomarkers persist. Sustainability is also addressed through the valorization of agrifood by-products and green extraction processes. This review provides an integrative framework linking molecular mechanisms, advanced delivery technologies, clinical translation, and sustainability, offering a broader perspective than conventional reviews. Future perspectives emphasize multicenter trials, comparative designs, and the development of regulatory guidelines for nanoformulated bioactive compounds.