Exploiting Plant-Based Nanostructures for Cancer Theranostics: Mechanistic Advances, Phytobiological Challenges, and Future Pathways

Abstract

Cancer, a leading cause of global mortality, necessitates innovative therapeutic strategies beyond conventional modalities. Phytonanomedicine, which harnesses plant extracts for the green synthesis of multifunctional nanoparticles, represents a promising theranostic platform. This approach leverages phytochemicals as reducing and stabilizing agents to fabricate a diverse taxonomy of metallic, metal oxide, and hybrid nanostructures. The inherent biocompatibility and eco-friendliness of this method are coupled with the ability to engineer key physicochemical properties including size, shape, surface charge, and functionalization to dictate biological fate. These engineered nanoparticles function as integrative theranostic systems, enabling precision tumor imaging through modalities like MRI and photoacoustics, and delivering multimodal therapies via drug delivery, photothermal action, and intrinsic bioactivity. However, their journey from administration to action is governed by a complex in vivo odyssey involving circulation, targeting (passive EPR effect and active ligand strategies), cellular uptake, and clearance. Despite significant promise, the field faces a critical translational chasm marked by challenges in reproducible synthesis, a complex and dynamic protein corona, ambiguous regulatory pathways, and biological barriers like tumor heterogeneity. To bridge this gap, future trajectories must pioneer next-generation, stimuli-responsive nanoplatforms, converge with AI and omics for rational design, and move toward personalized medicine through biomarker integration. Ultimately, the sustainable clinical translation of phytonanomedicines requires a cohesive roadmap that marries green chemistry principles with robust manufacturing and innovative clinical trial designs, positioning plant-derived nanotherapeutics as a viable paradigm for next-generation oncology.