Investigating the anti-proliferative effect and cytotoxicity of violet extract against SCC cells in vitro

Malignancies are the main cause of death in developed countries and the second cause of death in developing countries. Head and neck squamous cell carcinoma is the sixth most common cancer worldwide and standard treatments have failed to improve its survival rate in the past four decades. In addition, these treatment modalities give rise to various complications. Recently, research has focused on natural substances with anti-neoplastic properties that are specifically directed against malignant cells and have less potential for complications. The aim of this study was to evaluate the selective inhibitory and cytotoxic effects of violet extract on malignant cells compared to normal cells.
In this in vitro study, photometry and optical density (OD) techniques were used for MTT test to assess the cytotoxicity of violet extract at a wavelength of 560 nm using an ELISA reader. The cell survival rate was calculated by dividing the difference of blank OD in the treated cells by the difference of blank OD in control cells. Data were analyzed with two-way ANOVA to evaluate the concomitant effect of violet extract concentration and cell type on the percentage of residual viable cells; one-way and two-way ANOVA were used to evaluate the effect of the concentration of the extract on the percentage of residual viable cells separately for each cell line by using SPSS.
The results showed a significant relationship between the percentage of residual viable cells and the different concentrations of the extract (p value 0.26).
Based on the results, the cytotoxicity of violet extract on malignant cells (SCC) was similar to that on normal cells. Therefore, violet extract may not be useful as a natural substance, with less side effects, to selectively inhibit malignant cells.