Nanomedicine for colorectal cancer treatment: advances in targeted and intelligent drug delivery systems

Colorectal cancer (CRC) remains one of the leading causes of cancer-related mortality worldwide. Conventional treatment modalities, including chemotherapy, radiotherapy, and surgery, are frequently limited by poor tumor selectivity, systemic toxicity, inadequate drug penetration, and multidrug resistance. This review summarizes recent advances in nanomedicine-based therapeutic strategies for improving the efficacy and precision of CRC treatment. Recent literature on nanomedicine for CRC was critically reviewed, focusing on the design and therapeutic applications of lipid-based nanoparticles, polymeric nanoparticles, dendrimers, and inorganic nanomaterials. Particular emphasis was placed on passive and active targeting, tumor microenvironment-responsive delivery systems, and emerging approaches, including gene therapy, immunotherapy, photothermal therapy, and theranostic nanoplatforms. Challenges associated with clinical translation were also evaluated. Nanomedicine-based drug delivery systems significantly improve drug solubility, stability, bioavailability, and tumor-specific accumulation while reducing off-target toxicity. Targeted and stimuli-responsive nanocarriers enhance intracellular drug delivery, overcome biological barriers, and improve therapeutic outcomes in preclinical CRC models. Multifunctional nanoplatforms integrating diagnostic and therapeutic capabilities further support personalized cancer management. However, tumor heterogeneity, limited in vivo delivery efficiency, potential long-term toxicity, manufacturing scalability, and regulatory complexities continue to hinder widespread clinical translation. Nanomedicine offers a promising platform for precision treatment of colorectal cancer by enhancing therapeutic efficacy and minimizing adverse effects associated with conventional therapies. Continued advances in intelligent nanocarrier engineering, multi-targeted delivery systems, artificial intelligence-assisted formulation, and clinically relevant disease models are expected to overcome current translational barriers and facilitate the successful integration of nanomedicine into routine clinical management of CRC.