Figure 2E,F showed that compared with the control group, intracellular GSH level decreased after LH treatment in SW1990 cells. Next, to determine increased intracellular ROS levels may act on LH-induced cell growth inhibition or apoptosis, the antioxidant NAC and antioxidant enzyme SOD was added to the cancer cell lines before further LH treatment. The results showed that pretreatment with NAC or SOD partly counteracted LH-induced cell growth inhibition (Figure 2G,H), intracellular generation of ROS (Figure 2I,J), and apoptosis in SW1990 cells. (Figure 2K,L). This evidence concerns the gene SOD1 and cancer.