In Vitro Inhibition of MCF-7 Human Breast Cancer Cells by Essential Oils of Rosmarinus officinalis, Thymus vulgaris L., and Lavender x intermedia

Background: The essential oils of traditional medicinal plants, including Rosmarinus officinalis, Thymus vulgaris L., and Lavender x intermedia contain anticancer compounds such as lavandulyl acetate, rosmarinic acid and thymol. The aim of this study was to investigate the anticancer effects of the essential oils of R. officinalis, T. vulgaris L., and L. x intermedia on MCF-7 cells. Methods: Essential oils were prepared from R. officinalis, T. vulgaris L., and L. x intermedia plants. Then, MCF-7 and Hu02 cells were treated with different concentrations of these essential oils for a given time. The 3-[4,5-dimethylthiazol- 2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay was used to determine the cellular viability and cytotoxicity in response to treatment with different extract concentrations. The morphological changes were studied by Hoechst and propidium iodide staining. The results were analyzed using the one-way ANOVA and Tukey test. Results: All three essential oils inhibited the viability of the MCF-7 cell line in a dose-dependent manner. T. vulgaris L. was more potent against MCF-7 cells at 400 μg/ml concentration (IC = 48.01 ± 0.94), while R. officinalis was moderate at 50 800 μg/ml concentration (IC = 47.39±0.91) and the concentration for L. x 50 intermedia was 400 μg/ml (IC = 47.39 ± 0.91). Conclusion: R. officinalis, T. vulgaris L. and L. x intermedia show cytotoxic activity against breast cancer in vitro. T. vulgaris represents a potentially selective cytostatic factor and a safe target for future development of anticancer agents.