Although some reports showed that both mRNA and protein expressions of WIF1 were downregulated in prostate, breast, lung, and bladder cancers, hypermethylation of CpG islands in the WIF1 promoter region has been observed in some types of cancer [3, 18, 20], suggesting that loss of WIF1 expression may also contribute to carcinogenesis. Here, WIF1 is linked to urinary bladder cancer.