Characterization of the Eugenol Effects on the Bioenergetic Profile of SCC-4 Human Squamous Cell Carcinoma Cell Line

Eugenol (EU), the active ingredient in clove oil, is commonly used as successful therapeutic compound in dentistry due to its antiseptic and anti-inflammatory effects. Recent research studies suggest that eugenol has also a potential anti-cancer effect. This study was thereby purported to assess the effects of EU on the bioenergetic profile of the SCC-4 human squamous cell carcinoma cell line. To this aim, SCC-4 cells were treated for 24 hours with free EU and EU incorporated in polyurethane structures (50 mu M each). Oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) were measured using the Seahorse XF-24e extracellular flux analyzer (Agilent Technologies Inc.). Analysis of the SCC-4 bioenergetic profile was performed in the presence of the classic modulators of the electron transport chain: oligomycin, FCCF, and antimycin A+rotenone. Our data showed that cells stimulated with free EU induced a decrease of OCR linked parameters and an increase of ECAR, effects that were abolished by the incorporation of EU in polyurethane structures. In conclusion, free eugenol elicits inhibitory effects on mitochondrial respiration in the SCC-4 cell line, a result that might be suggestive for its anti-tumoral effects.