The chemical structure of scutellarein (SCU) and the effect of SCU treatment in HCC cell lines and HaCaT cells. (a) Structure of SCU. (b) Cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay with SCU (0, 25, 50, 100, 150, and 200 μM) for 48 h in HaCaT cells. (c) Cell viability was measured by MTT assay with SCU (0, 25, 50, 100, 150, and 200 μM) for 24 and 48 h in HepG2 cells. (d) Cell viability was measured by MTT assay with SCU (0, 25, 50, 100, 150, and 200 μM) for 24 and 48 h in Huh-7 cells. The results obtained from three independent experiments were expressed as mean ± standard deviation (SD) compared with the control group. ** p < 0.01, *** p < 0.001.