RT Journal Article SR Electronic T1 Effects of TiO2 Nanoparticles on Cytotoxic Action of Chemotherapeutic Drugs Against a Human Oral Squamous Cell Carcinoma Cell Line JF In Vivo JO In Vivo FD International Institute of Anticancer Research SP 209 OP 215 VO 28 IS 2 A1 RENE GARCIA-CONTRERAS A1 ROGELIO J. SCOUGALL-VILCHIS A1 ROSALIA CONTRERAS-BULNES A1 YOSHIAKI ANDO A1 YUMIKO KANDA A1 YASUSHI HIBINO A1 HIROSHI NAKAJIMA A1 HIROSHI SAKAGAMI YR 2014 UL http://iv.iiarjournals.org/content/28/2/209.abstract AB Background. Despite the rapid development of nanotechnology, the biological significance of TiO2 nanoparticles (NPs), possibly released from dental materials, is not well-understood. We investigated the effect of TiO2 NPs on the sensitivity of human oral squamous cell carcinoma (OSCC) cell line (HSC-2) to five popular chemotherapeutic agents. Materials and Methods. Viable cell number was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The aggregation and cellular uptake of TiO2 NPs were assessed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. Adsorption of TiO2 NPs to anticancer drugs was assessed by the antitumor activity recovered from the TiO2 NP-free supernatant. Results: When mixed with culture medium, TiO2 NPs instantly aggregated, and some particles were incorporated into the cells, exclusively in the vacuoles. TiO2 NPs showed no cytotoxicity nor hormetic growth stimulation at lower concentrations. Doxorubicin, melphalan, 5-fluorouracil and gefitinib were cytotoxic, whereas docetaxel was cytostatic with or without TiO2 NPs. TiO2 NPs, at wide concentration ranges (0.2-3.2 mM), did not significantly affect the adsorption of NPs to any of these anticancer drugs, nor affected their cytotoxic or cytostatic activity. Conclusion: This experimental study demonstrated for the first time that TiO2 NP do not affect the antitumor potential of chemotherapeutic agents against the HSC-2 OSCC cell line.