Figure 3.
Melanoma cell migration stimulated by 12-O-tetradecanoylphorbol-13-acetate (TPA) was attenuated by adding dipotassium glycyrrhizinate (DPG) (A) TPA stimulates the migratory effect of SK-MEL-28 in a time-dependent trend, in comparison with untreated control cells. In contrast, DPG inhibits the migration of SK-MEL-28 in a time-dependent trend compared to untreated control cells. Finally, SK-MEL-28 cell migration stimulated by TPA was attenuated by adding DPG. (B) A significant increase in the migration of SK-MEL-28 cells was observed in the presence of TPA stimulation for 24 h (p-value = 0.002) and 48 h (p-value = 0.09). Furthermore, migration of SK-MEL-28 cells stimulated by TPA was attenuated by adding DPG cells by wound-healing assay (48 h: p-value = 0.004; 72 h: p-value = 7.0 × 10−4). (C) An increased Matrix Metalloproteinase 9 (MMP-9) mRNA expression level was observed compared to control cells SK-MEL-28 cells stimulated by TPA (p-value = 0.0004). Otherwise, decreased MMP-9 expression was observed in those DPG-treated SK-MEL-28 cells compared to untreated cells (p-value = 0.31) and in TPA plus DPG-exposure melanoma cells compared to control one (p-value = 0.39). In addition, the MMP-9 expression level was inhibited by DPG in melanoma cells stimulated by TPA compared to only TPA-treated cells (p-value = 0.002) after 24 h of treatment. These results suggested that DPG has an anti-migratory effect on SK-MEL-28 cells. For all assays, data represent means and standard deviations of a representative experiment performed in triplicate. Statistics were performed in a two-tailed T-test with an alpha error of 0.05.