For example, methylation of the promoter regions of genes such as those in the DKK family (e.g., DKK1, DKK3), the SFRP family (e.g., SFRP1, SFRP2), and WIF1 (Wnt Inhibitory Factor 1) leads to their downregulation or silencing, thereby lifting the inhibition on the Wnt pathway and promoting tumor cell proliferation and survival.260. This evidence concerns the gene DKK1 and neoplasm.