DKK3 and renal cell carcinoma: Studies into the mechanisms behind reduced DKK3 expression have revealed histone modification in cancers such as renal cell carcinoma (Ueno et al., 2011), and hypermethylation of the DKK3 promoter in a vast number of human cancers including lung, bladder, breast, and leukemia (reviewed by Veeck and Dahl, 2012).