Advances in nanotechnology for colorectal cancer: a smart targeting and theranostics approach

Colorectal cancer remains one of the most common and deadly malignancies globally, with high mortality rates, particularly in advanced stages. Conventional therapies such as surgery, chemotherapy, and radiotherapy, though beneficial, often suffer from drawbacks including systemic toxicity, multidrug resistance, and poor tumor selectivity. Recent progress in nanotechnology has introduced innovative theranostic strategies that integrate diagnosis and treatment using nanoparticle-based platforms. These nanocarriers can be tailored for both passive and active tumor targeting, as well as stimuli-responsive drug release (e.g., pH, redox, and enzymatic triggers), and provide real-time imaging guidance. Novel approaches, such as the use of Fe₃O₄-based photothermal nanoparticles to induce ferroptosis and immunogenic cell death, or polyphenol-loaded nanoparticles to enhance biocompatibility and therapeutic efficacy, have demonstrated significant potential in colorectal cancer models. Additionally, hydrogels and biopolymer-based systems offer controlled, localized delivery, reducing systemic exposure and side effects. Imaging-assisted therapies, such as MRI-guided photothermal therapy, further refine precision treatment. However, challenges such as tumor heterogeneity, nanoparticle clearance, biological barrier penetration, and clinical scalability remain to be addressed. This review discusses the latest advancements in nanoparticle-mediated colorectal cancer diagnosis and therapy, while also outlining key translational barriers and future directions toward clinically viable nanomedicine strategies.