The APC gene encodes a tumor suppressor protein that acts as an antagonist of the Wnt signaling pathway. APC promotes rapid degradation of beta-catenin and participates in Wnt signaling as a negative regulator. APC is also involved in other processes including cell migration, cell adhesion, transcriptional activation and apoptosis. Disease-associated mutations tend to be clustered in a small region designated the mutation cluster region (MCR) and result in a truncated protein product. APC mutations have been reported in 3-10% of prostate cancers. In some studies, a high-level of APC promoter methylation was shown to be an independent predictor of a poor prognosis in prostate cancers. However, further studies are needed to explore the clinical value of APC mutations in these tumors.