Cerium oxide nanoparticles exert antitumor effects and enhance paclitaxel toxicity and activity against breast cancer cells.

Cerium oxide nanoparticles (CeONPs) displayed cytotoxic properties against some cancer cells. However, there is very limited data about the possible antitumoral potential of them in breast cancer cells when used alone and/or together with a chemotherapeutic drug. We investigated the effects of CeONPs alone or in combination with paclitaxel (PAC) on healthy or carcinoma breast cells. After human breast cancer cells (MCF-7) treated with CeONPs alone or together with PAC for 24, 48, and 72 h, the effects of CeONPs on cell viability, apoptosis, migration, and adhesion were investigated. All cell viability and IC50 values of CeONPs and PAC treatments in healthy breast cells (HTERT-HME1) were higher than MCF-7 cells. They showed higher cytotoxicity against MCF-7 cells. CeONPs (10, 20, and 30 mM) and/or abraxane (AB) (2 μM) significantly decreased cell viability values in MCF-7 cells. All CeONPs concentrations increased the number of apoptotic MCF-7 cells. CeONPs (20 and 30 mM) alone or in combination with AB for 72 h treatment also significantly increased the apoptosis in compared to AB alone. CeONPs and/or AB can significantly inhibit the migratory ability of breast cancer cells. The migration rates in co-treated groups with CeONPs and AB were lower than CeONPs treatments. Higher concentrations of CeONPs alone or together with AB inhibited cell adhesion. Our results showed CeONPs can increase cytotoxicity and apoptosis and decrease cell migration and cell adhesion when used alone or together with AB. Therefore, combination of chemotherapeutics with CeONPs may provide a good strategy against cancer.