CHEK2 and brain cancer: Figure 6A,B shows the results of our Western blot analysis of cellular proteins extracted from the brain cancer cell lines treated with RTA404 (0, 1, 1.5, and 2 μM). We measured the relative intensities of cyclin A2, NRF2, p-CHK2, CHK1/2 and p21 expression. In this experiment, we measured the relative intensities of cell cycle regulators such as cyclin A2’s expression. As Figure 6 shows, the relative intensity of cyclin A2 was not significantly different compare with the control group after RTA404 treatment.