Cytotoxic and mutagenic capacity of TTO and terpinen-4-ol in oral squamous cell carcinoma

The essential oil of Melaleuca Alternifolia (tea tree oil - TTO) consists of about 100 components, and the highest concentration are terpinen-4-ol. Studies of their cytotoxic capacity have shown effect on malignant neoplastic lineages. The aim of this study was to evaluate the cytotoxic and mutagenic capacity of TTO and main soluble components, terpinen-4-ol and gama-terpinene in cell cultures. Two lineages of oral squamous cell carcinoma and a keratinocyte cell were analyzed: (1) colorimetric analysis Metiltetrazolium (MTT); (2) Micronucleus assay. The results were expressed as susceptibility tests and degree of mutagenicity. The statistical test used in the analysis was one-way ANOVA (Tukey test). The IC50 values obtained from the MTT analysis of cells exposed to TTO were 0.2% for HaCaT, 0.14% for HSC-3, and 0.17% for SCC-25. For exposure to terpinen-4ol, IC50 values were 0.5%, 0.3% and 0.45% for HaCaT, HSC-3 and SCC-25, respectively. The gamma-terpinene didnt show significant cytotoxic activity, therefore it was impossible to calculate the IC50. TTO and terpinen-4-ol was unable to produce mutagenicity in all the lineages. In conclusion, both the TTO and terpinen-4-ol had cytotoxic capacity on HaCaT, HSC-3 and SCC-25. TTO and terpinen-4-ol wasnt mutagenic. In this sense, our study provides new perspectives on the potential use of TTO and terpinen-4-ol for the development of new alternative therapies to treat topically locally oral squamous cell carcinoma. This study can be related