SIRT1 and cancer: Figure 5A clearly shows that the ROS level was decreased in SIRT1-KD cells and increased in SIRT1-OE cells, suggesting the SIRT1 expression could affect the ROS level. After treatment with resveratrol, the ROS level was increased in both cell lines, indicating that resveratrol may cause the accumulation of ROS in cancer cells. As shown in Figure 5B, the ROS level was significantly increased in RanGap1-OE cells, although no apparent change in RanGap1-KD cells was observed.