@article{
author = "Pešić, Milica and Podolski-Renić, Ana and Stojković Burić, Sonja and Matovic, Branko and Zmejkoski, Danica and Kojic, Vesna and Bogdanovic, Gordana and Pavicevic, Aleksandra and Mojovic, Milos and Savic, Aleksandar and Milenkovic, Ivana and Kalauzi, Aleksandar and Radotic, Ksenija",
year = "2015",
abstract = "Data on medical applications of cerium oxide nanoparticles CeO2 (CONP)
are promising, yet information regarding their action in cells is
incomplete and there are conflicting reports about in vitro toxicity.
Herein, we have studied cytotoxic effect of CONP in several cancer and
normal cell lines and their potential to change intracellular redox
status. The IC50 was achieved only in two of eight tested cell lines,
melanoma 518A2 and colorectal adenocarcinoma HT-29. Self-propagating
room temperature method was applied to produce CONP with an average
crystalline size of 4 nm. The results confirmed presence of Ce3+ and O2-
vacancies. The induction of cell death by CONP and the production of
reactive oxygen species (ROS) were analyzed by flow-cytometry. Free
radicals related antioxidant capacity of the cells was studied by the
reduction of stable free radical TEMPONE using electron spin resonance
spectroscopy. CONP showed low or moderate cytotoxicity in cancer cell
lines: adenocarcinoma DLD1 and multi-drug resistant DLD1-TxR, non-small
cell lung carcinoma NCI-H460 and multi-drug resistant NCI-H460/R, while
normal cell lines (keratinocytes HaCaT, lung fetal fibroblasts MRC-5)
were insensitive. The most sensitive were 518A2 melanoma and HT-29
colorectal adenocarcinoma cell lines, with the IC50 values being between
100 and 200 mu M. Decreased rate of TEMPONE reduction and increased
production of certain ROS species (peroxynitrite and hydrogen peroxide
anion) indicates that free radical metabolism, thus redox status was
changed, and antioxidant capacity damaged in the CONP treated 518A2 and
HT-29 cells. In conclusion, changes in intracellular redox status
induced by CONP are partly attributed to the prooxidant activity of the
nanoparticles. Further, ROS induced cell damages might eventually lead
to the cell death. However, low inhibitory potential of CONP in the
other human cell lines tested indicates that CONP may be safe for human
usage in industry and medicine. (C) 2015 Elsevier Ireland Ltd. All
rights reserved.",
journal = "Chemico-Biological Interactions",
title = "Anti-cancer effects of cerium oxide nanoparticles and its intracellular
redox activity",
volume = "232",
doi = "10.1016/j.cbi.2015.03.013",
pages = "85-93"
}