The anticancerogenic activity of the essential oil of Melissa officinalis L. against continuous cell culture of HEp-2 cells derived from human laryngeal cancer was investigated. The effects of the essential oil was compared with the anticancerogenic effects of the Methotrexate (MTX) and Vepesid. The various concentrations of MTX, Vepesid and the essential oil on cells was examined by the morphological changes they induced on the cells and by flow cytometry analysis. The oils like MTX and Vepesid induced cytopathological changes. Whilst the essential oil terminated the cells of the G1 and S phases of the cell cycle, MTX was achieve at the S and G2 phases and Vepesid of the G1 phase was observed. These results show that the essential oil obtained from the M. officinalis L. has anticancerogenic effects
