As shown in Table 1, all (100%) of 5 adenocarcinomas expressed WT1 ranging from 8.3 × 10-1 to 2.8 × 100 (WT1 expression level in A549 lung cancer cells was defined as 1.0), and 15 squamous cell lung cancer tissues expressed WT1 at levels ranging from 0.3 × 10-2 to 5.4 × 100. Here, WT1 is linked to lung cancer.