Berberine and As
inhibit the phosphorylation of ERK and decrease the ornithine decarboxylase (ODC), MT1-MMP, and MMP2 protein levels. C6 glioma cells were incubated for 24 h with 10 μM berberine (Ber) or 5 μM As2O3 (As), and with 10 μM berberine and 5 μM As2O3 (A+Ber). Total cell lysates were prepared and subjected to Western blot analysis. Protein levels of phosphorylated ERK1/ERK2 and non-phosphorylated ERK1/ERK2, and ODC, MT1-MMP and MMP2 were detected using the respective monoclonal antibodies (A). The condition serum free media were collected for gelatin zymography analysis from C6 glioma and U-87 cells. Determined activities of these proteins were subsequently quantified by densitometric analysis with the value of controls set at 100% as shown in the graph. The quantitative data were presented as the mean of three repeats from one independent experiment. Other data in this figure is presented as mean ± SD of three independent experiments. * and ** indicate means that are significantly different when compared to the control group of C6 with P < 0.05 and P < 0.01, respectively. # and ## indicate means that are significantly different when compared to the control group of U-87 with P < 0.05 and P < 0.01, respectively.