Harnessing nanoparticles to improve toxicity after head and neck radiation

This article reports the evaluation of cerium oxide (CeO2) nanoparticles' ability to decrease xerostomia and radiation-induced dermatitis in mice after head and neck radiation. Mice were irradiated using an IC160 x-ray system. Two cohorts were included: (A) No-radiation and (B) 30 Gy/6 fractions, and were randomized into three groups: (1) saline, (2) 15 nM CeO2 and (3) 15 mu M CeO2. Stimulated salivary flow and radiation-induced dermatitis were evaluated post radiation. Stimulated sialometry demonstrated improved salivary production in all CeO2 groups in comparison with controls (flow: 204 vs. 115 mu L/10 minutes, P = 0.0002). One week post radiation, G-III dermatitis decreased in the 15 mu M group in comparison with controls (10% versus 100% incidence, respectively). There was decreased skin hyperpigmentation at 12 weeks in the 15-mu M group in comparison with 15-nM and non-CeO2 groups (50%, 70%, and 90% G-II, respectively). This study suggests that CeO2 may be radioprotective for salivary production and reduces G-III dermatitis and skin hyperpigmentation incidence. CeO2 as radioprotectant may be a feasible concept during radiotherapy. From the Clinical Editor: This study demonstrates in a mouse model that cerium oxide (CeO2) nanoparticles may provide an important mechanism in preventing radiation induced xerostomia, a common complication of head and neck radiation treatments. (C) 2012 Elsevier Inc. All rights reserved.