Panoply™ Human SOD1 Knockdown Stable Cell Line

Copper/zinc superoxide dismutase (SOD1) catalyzes the dismutation of superoxide anions (O2•−) into hydrogen peroxide (H2O2); elevated SOD1 activity and expression levels sustain high intracellular H2O2 concentrations, thereby activating signaling pathways-such as ERK, PI3K-Akt, and NF-κB-that are critical for cancer initiation and progression. In this study, researchers treated cancer and normal cells with a specifically designed SOD1 inhibitor, LD100. The results demonstrated that the changes in reactive oxygen species (ROS) levels induced by specific SOD1 inhibition simultaneously suppressed signaling pathways (and their crosstalk) that support cancer cell growth while activating pathways that promote cell cycle arrest and apoptosis. These regulated pathways constitute an ROS signaling network that determines the fate of cancer cells; a similar regulation of this ROS signaling network was observed in SOD1-knockdown cells. These findings help elucidate the mechanisms of action of copper-chelating anticancer drugs and provide guidance for the design of small-molecule anticancer agents that target SOD1 and disrupt ROS signaling pathways.

Previous studies have shown that LD100 treatment induces apoptosis in HeLa cells. As expected, flow cytometry data revealed that increasing concentrations of LD100 led to a significant rise in the proportion of apoptotic and dead DU145 cells, whereas the corresponding proportion in RWPE-1 cells showed only a slight increase (Figure 1a). Similarly, SOD1 knockdown selectively promoted apoptosis in cancer cells (HeLa and DU145) but did not induce such effects in normal cells (RWPE-1) (Figure 1b). Furthermore, compared to the untreated group, no large colony formation was observed in DU145 and HeLa cells treated with 50 μM LD100 for 1 to 2 weeks; under the same experimental conditions, however, this treatment did not affect the colony-forming ability of normal RWPE-1 cells. These results indicate that the specific inhibition of SOD1 significantly suppresses cancer cell proliferation and growth by inducing apoptosis, without affecting normal cells.

Figure 1. The specific SOD1 inhibition induces apoptosis and hinders the formation of cancer cell colonies. (Li X, et al., 2019)