Selenium and Iron Oxide Nanocomposites for Magnetically-Targeted Anti-Cancer Applications

Abstract

Iron oxide nanoparticles (IONP) are already well-established in the medical field due to their ability to improve contrast in magnetic resonance imaging (MRI) and for their external magnetic control in the body. Moreover, selenium has been shown to kill numerous cancer cells at lower concentrations that IONP (e.g., 1 μg/ml). Selenium is a trace mineral of growing interest in cancer treatment since it is an essential nutrient in the human body and can interfere with thiolcontaining proteins necessary for cancer cells to function. For the above reasons, the goal of this in vitro study was to combine the above chemistries for the first time to develop composite nano-vehicles for magnetically targeted cancer therapy. The suggested design was an IONP core, stabilized by chitosan and decorated with selenium. Two different types of IONP cores were produced. This was followed by different chitosan and selenium coating methods. The particles were characterized for size, shape, zeta potential and magnetic properties. Finally, the most promising products were tested for cancer killing properties on MB-231 breast cancer cells. Results of this pioneering study showed that the most promising iron-selenium nanocomposites consisted of an iron oxide core produced by thermal decomposition, followed by a silane ligand exchange, a chitosan coating and selenium decoration. The particles were 5-9 nm in diameter, with a zeta potential of 29.59 mV and magnetic properties of 35.932 emu/g. Moreover, the novel nanoparticles had concentration dependent cancer killing properties. Specifically, after just 1 day of incubation, breast cancer cell viability was reduced to 40.5% in the presence of 1 μg/ml of these composite nanoparticles (and statistically reduced at even 0.1 μg/ml), without using a chemotherapeutic pharmaceutical drug. This is a significant finding since neither chemotherapeutic pharmaceutical drugs, infrared stimulation, nor magnetism were used. In this manner, this study introduces a brand new composite nanoparticle consisting of iron oxide and selenium which should be further studied for a wide range of magnetically targeted anticancer applications.

H2Se Induces Reductive Stress in HepG2 Cells and Activates Cell Autophagy by Regulating the Redox of HMGB1 Protein under Hypoxia

“…Selenium plays a possible role in cancer prevention largely because of its antioxidant properties40. As a component of antioxidant selenoproteins (e.g., glutathione peroxidase), selenium can have antioxidant effects by reducing the formation of free radicals and reactive oxygen species1, 41. Most importantly for this study, selenium is considered to have cancer treatment properties.…”

Advanced biomaterials for cancer immunotherapy

“…Because iron oxide NPs have been approved for human use as MRI contrast agents and their degradation products are good for the body’s iron store, iron oxide NPs have been increasingly used simultaneously for cancer immunotherapy and imaging [ 221 – 223 ]. Iron oxide NPs can be modified with many cargos to improve the antitumor immune response, such as heat shock protein 70 (Hsp70) [ 224 ], R837 and Poly(I:C) [ 225 ], CpG-ODN [ 226 ], and ICG [ 227 ].…”

Selenium Nanoparticles for Biomedical Applications: From Development and Characterization to Therapeutics

“…Se:IONPs reduced the viability of breast cancer cells, however the study itself did not clarify the mechanisms behind the antitumor activity. [ 232 ]…”