Recent progress and drug delivery applications of surface-functionalized inorganic nanoparticles in cancer therapy

Background Cancer remains a major global health burden and existing therapeutic approaches face substantial challenges such as drug resistance, poor selectivity, heterogeneity, and the complex tumor microenvironment. Nanotechnology has evolved into a promising tool with huge potential for application in the field of medicine. Recently, inorganic nanoparticles (INPs) have been widely explored for cancer therapy because of their distinct tunable physicochemical properties, biocompatibility, and versatile preparation methods. In addition, surface functionalization of INPs has further improved therapeutics efficacy by modulating their features, such as poor aqueous solubility, in vivo stability, potential toxicity, enhanced cancer targeting, and reduced binding to healthy cells. Area covered In this review, we briefly highlight a few of the most commonly used INPs in cancer therapy, along with their basic features and fabrication methods. Strategies, commonly employed materials and reasons for surface functionalization of INPs have also been described. Furthermore, the latest drug delivery and therapeutic applications of surface-functionalized INPs in various cancers were extensively reviewed. This review concludes with a future outlook and a few limitations of surface-functionalized INPs that hinder their clinical application. Expert opinion The presented data undoubtedly prove the potential of surface-functionalized INPs to improve therapeutic efficacy, cellular uptake, and tumor growth inhibition of anti-tumor drugs, thereby minimizing their limitations in cancer therapy. However, functionalized INPs have a negligible presence in the market for cancer therapy despite their promising potential. Appropriate designing and clinically relevant testing may facilitate their clinical translation into safe and effective cancer therapy in the near future.