In contrast to the large nucleoli in Sod1+/+ KP lung tumor tissues, nucleoli in Sod1−/− tumors were much smaller and more fragmented (Fig. 7b, c), indicating that SOD1 is required for nucleolar hypertrophy and hyperactive ribosome biogenesis in the NSCLC tumors. Here, SOD1 is linked to non-small cell lung carcinoma.