Unraveling the Multifunctional and Translational Paradigm of Nanoparticulate Systems against Colorectal Cancer

Colorectal cancer (CRC) is a health burden due to its high mortality rate, recurrence rate, and drug resistance. The limitations of traditional methodologies (such as radiotherapy, chemotherapy, surgery, and targeted active ingredients) include inefficient delivery to tumor tissue, systemic toxicity, drug resistance, and poor specificity. Hence, drug delivery through micro- and nanoparticulate systems offers innovations and can address these obstacles successfully. The design, functionality, and translational potential of particulate systems specifically designed for CRC treatment are reviewed in this study. Next, this review discusses various primary aspects, including the types of carriers (polymeric, solid lipid, inorganic, and hybrid nanoparticles/NP), their particulate physical attributes (size, shape, surface charge, composition), and factors affecting drug encapsulation and release kinetics that affect the basic design principles. Additionally, this review unfolds a discussion over targeting approaches, such as active ligand-mediated targeting, passive EPR-based accumulation, and stimulus-responsive systems activated by external stimuli, pH, enzymes, redox, or even the microbiome. Furthermore, conventional chemotherapeutics, phytochemicals and nutraceuticals, gene-based therapies (siRNA, miRNA), and combinatorial modalities (chemo and immunotherapy, photothermal, photodynamic) are included in the therapeutic payloads. Moreover, in vitro, in vivo, and clinical-stage nanoparticulate systems are highlighted with translational advancements. Specifically, this review emphasizes the benefits offered, including enhanced solubility, stability, targeted distribution, and multifunctionality (imaging, triggered release). In addition, primary challenges to translation, such as regulatory, scalability, reproducibility, biological processes, and long-term safety issues, are also discussed. Conclusively, innovative approaches like regulatory frameworks, microbiome-driven delivery designs, aspects of artificial intelligence/machine learning (AI/ML)-guided optimization, and stealth and biomimetic hybrid particulates can be beneficial from futuristic aspects. Suggestively, to expedite the transition from NP invention to effective CRC therapeutics, a translational roadmap is required that encourages the combination of modern materials science, computational design, and clinical validation.