Cyclosativene (CSV) is a tetracyclic sesquiterpene found in the essential oils of Centaurea cineraria (Asteraceae) and Abies magnifica A. Murray (Pinaceae) plants. To the best of our knowledge, its cytotoxic, genotoxic and oxidant effects have never been studied on any cell lines. Therefore, we aimed to investigate the in vitro antiproliferative and/or cytotoxic properties, antioxidant/oxidant activity and genotoxic damage potential of CSV in healthy neurons and N2a neuroblastoma (N2a-NB) cell cultures. After treatment with 10-400 mu g/ml of CSV for 24 h, cell proliferation was measured by the MTT (3,(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The antioxidant activity was assessed by the total antioxidant capacity (TAC) and total oxidative stress (TOS) assays. To evaluate the level of DNA damage, single cell gel alkaline electrophoresis (SCGE) was used. The MTT assay showed that the application of CSV significantly reduced cell viability in both cell types. CSV treatments at higher doses led to decreases of TAC levels and increases of TOS levels in neuron and N2a-NB cells. The mean values of the total scores of cells showing DNA damage were not found to be significantly different from the control values in both cells. In conclusion, this study suggests that CSV has weak anticancer potential.