SOD1 and cancer: Potentially, combination treatment of TM with doxorubicin, MMC, 4-HPR, or 5-FU may exert additional synergistic effects when combined with other agents thought to modulate the antioxidant functions of cancer cells such as 2-methoxyestradiol (SOD inhibitor) or drugs leading to glutathione depletion such as buthionine-sulfoximine.