We further show that two SOD1 inhibitors (ammonium tetrathiomolybdate [ATTM] and Lung Cancer Screen-1 [LCS-1]) and one chemical mimetic (2-methoxyestradiol [2ME2]) phenocopy the SOD1 silencing results by inducing preferential killing within BLM- and CHEK2-deficient cells. Here, SOD1 is linked to lung cancer.