Using Inorganic Nanoparticle-Based Drug Delivery Systems against Human Colon Cancer Cells: Effect of Particle Size on Anticancer Activity

Today’s nanoparticle technology enables the synthesis of nanoparticle-based drug delivery systems with desired size, shape, and materials especially for the applications of cancer nanomedicine. Thereby, understanding impact of particle sizes on anticancer activity will contribute to development of new drug delivery systems in cancer therapy. For this reason, in this study, two different sized nanoparticles (with ~55 and 314 nm) were used as drug delivery systems and the effects of their size on the cellular uptake, cytotoxicity and apoptosis were investigated against the human colon carcinoma Caco-2 and HCT-116 cells. The results demonstrated that small nanoparticles promoted fast nanoparticle accumulation in both cancer cells in comparison to large particles. Small nanoparticles exhibited higher cytotoxicity in cancer cells with lower half maximal inhibitory concentration (IC50) values than large nanoparticles in 48 h. On the other hand, both nanoparticles showed similar IC50 values after 72 h prolonged exposure. Moreover, it was found that small nanoparticles increased the number of apoptotic cells in 24 h, whereas large nanoparticles induced apoptosis when exposure time increased to 72 h. These observations show that small sized drug delivery systems could be more efficient for improving the anticancer effects of chemotherapeutic drugs against human colon carcinoma as compared to large sized drug delivery systems