Kim et al. (2005) demonstrated that methylation of RUNX3 promoter sequence confers a 100-fold increased risk of developing bladder cancer (OR, 107.55). RUNX3 methylation also appears to be positively associated with cancer stage (OR, 2.95), recurrence (OR, 3.70), and progression (OR, 5.63), which suggests that RUNX3 not only inhibits cancer initiation but also suppresses the aggressiveness of primary bladder cancers. Thus, the methylation status of RUNX3 may be a better diagnostic marker for bladder cancer than previously described markers. This evidence concerns the gene RUNX3 and cancer.