RESUMO
BACKGROUND: The inhibitory effect of selenium nanoparticles (SeNPs) on cancer cells has been reported in many studies. In this study, the purpose was to compare the in vitro effects of SeNPs and calcium sulfate coated selenium nanoparticles (CaSO4@SeNPs) on breast cancer cells. METHODS: CaSO4@SeNPs and SeNPs were chemically synthesized and characterized with Field Emission Scanning Electron Microscope (FESEM) and energy-dispersive X-ray spectroscopy (EDX). By applying MTT assay, the cytotoxicity effect of both nanomaterials on the 4T1 cancer cells was investigated. RESULTS: While LD50 of SeNPs on 4T1 cancer cells was 80 µg, the LD50 of CaSO4@SeNPs was reported to be only 15 µg. The difference between the inhibition rates obtained for SeNPs and CaSO4@SeNPs was statistically significant (p=0.05). In addition, at higher concentrations (50 µg) of CaSO4@SeNPs, the cytotoxicity was 100% more than SeNPs alone. CONCLUSION: According to the result of the present work, it can be concluded that decoration of SeNPs with calcium sulfate leads to an increase in potency by decreasing the effective dose. This effect can be attributed to activation of intrinsic apoptosis signaling and/or pH regulatory properties of CaSO4@SeNPs. However, further studies are still needed to determine the exact corresponding mechanisms of this synergistic effect.
RESUMO
BACKGROUNDS AND AIMS: Selenium nanoparticles (SeNPs) have been reported to exhibit an inhibitory effect on cancer cells. In the present study, we aimed to compare the in vitro and in vivo effects of SeNPs and folic acid surface-coated selenium nanoparticles (FA@SeNPs) on breast cancer. METHODS: FA@SeNPs and SeNPs were chemically synthesized and characterized with different instrumental techniques. The cytotoxicity of both nanomaterials was evaluated against 4T1 cells. In addition, the intravenous administration effect of these nanomaterials (300 µg/week) on the lifespan and tumor size of cancer-bearing mice was investigated. RESULTS: Although the SeNPs showed an antiproliferative effect against the cell line, the cytotoxicity of the FA@SeNPs was higher than that of the SeNPs. A low concentration of FA@SeNPs (25 µg/mL corresponding to 8.75 µg/mL of elemental SeNPs) caused approximately 68% cell mortality. In the in vivo study, the nanomaterials decreased the tumor growth rate in cancerous mice in relation to the control group. FA@SeNPs were more effective than SeNPs. CONCLUSIONS: The combination of SeNPs and FA has a potent antiproliferative effect against 4T1 cells, significantly increases the lifespan, and prevents tumor growth.
