Thyme Oil & Cancer

Thyme belongs to the Lamiaceae family; due to its wide spectrum of pharmacological properties, it has been used in traditional medicine for thousands of years in countries of the Mediterranean basin. Essential oil of the most studied species, Thyme vulgaris, and its principal component thymol has been shown to have antifungal, antibacterial [1, 2], and antioxidant [3] activities. Therefore, thyme is usually employed as expectorant in upper respiratory tract infection, and thymol is often the main antiseptic ingredient in mouth rinses against gingivitis.

In 2007, Ait M’Barek and colleagues tested the cytotoxic effect of Moroccan endemic thyme (Thymus broussonetii) essential oil in human ovarian adenocarcinoma cell line (IGR-OV1) and its parental cell line resistant to three chemotherapeutic drugs currently used to treat the ovarian adenocarcinoma (adriamycin, vincristine, and cisplatinum) [58]. In this study all cell lines were sensitive to the cytotoxic effects of the essential oil, although they had a different degree of sensitivity reporting an IC50 ranging between 0.39 and 0.94%; importantly, the authors also showed that administration of the essential oil at the tumor site for 30 days in tumor bearing DBA-2 () mice inhibited tumor proliferation, reduced tumor volume, and delayed mouse mortality [4].

In human UMSCC1 head and neck squamous cell carcinoma (HNSCC) cells subtoxic concentrations of Thymus vulgaris essential oil stimulated proliferation and viability, while, at higher concentrations, dose-dependent cytotoxic effects were found [5]; under this experimental setting, the observed cytotoxicity induced by the essential oil was associated, as shown by a microarray-based mRNA expression profiling and pathway analysis, with the regulation of three pathways, namely, the interferon signaling, N-glycan biosynthesis, and ERK5 signaling that could be all involved in the effect of thyme essential oils on cancer cell growth and survival [6]. Interestingly, a recent study testing the cytotoxicity of ten essential oils (mint, ginger, lemon, grapefruit, jasmine, lavender, chamomile, thyme, rose, and cinnamon) identified thyme as the most effective on human prostate carcinoma (PC3), human lung carcinoma (A549), and human breast cancer (MCF7) cell lines [7].

 

1. S. Cosentino, C. I. G. Tuberoso, B. Pisano et al., “In-vitro antimicrobial activity and chemical composition of Sardinian Thymus essential oils,” Letters in Applied Microbiology, vol. 29, no. 2, pp. 130–135, 1999. View at Publisher · View at Google Scholar · View at Scopus


2. D. Kalemba and A. Kunicka, “Antibacterial and antifungal properties of essential oils,” Current Medicinal Chemistry, vol. 10, no. 10, pp. 813–829, 2003. View at Publisher · View at Google Scholar · View at Scopus


3. K. Miura, H. Kikuzaki, and N. Nakatani, “Antioxidant activity of chemical components from sage (Salvia officinalis L.) and thyme (Thymus vulgaris L.) measured by the oil stability index method,” Journal of Agricultural and Food Chemistry, vol. 50, no. 7, pp. 1845–1851, 2002. View at Publisher · View at Google Scholar · View at Scopus


4. L. Ait M’Barek, H. Ait Mouse, A. Jaâfari et al., “Cytotoxic effect of essential oil of thyme (Thymus broussonettii) on the IGR-OV1 tumor cells resistant to chemotherapy,” Brazilian Journal of Medical and Biological Research, vol. 40, no. 11, pp. 1537–1544, 2007. View at Publisher · View at Google Scholar · View at Scopus


5. S. Sertel, T. Eichhorn, P. K. Plinkert, and T. Efferth, “Cytotoxicity of Thymus vulgaris essential oil towards human oral cavity squamous cell carcinoma,” Anticancer Research, vol. 31, no. 1, pp. 81–87, 2011. View at Google Scholar · View at Scopus


6. Y. Zu, H. Yu, L. Liang et al., “Activities of ten essential oils towards Propionibacterium acnes and PC-3, A-549 and MCF-7 cancer cells,” Molecules, vol. 15, no. 5, pp. 3200–3210, 2010. View at Publisher · View at Google Scholar · View at Scopus

Thyme Oil & Cancer