Analysis of Wnt and ß-catenin Expression in Advanced Colorectal Cancer.

ABSTRACT

BACKGROUND: Wnt/ß-catenin signaling plays an important role in colorectal cancer (CRC). Wnt has many sub-types and it is uncertain which of them affect progression of CRC. PATIENTS AND METHODS: We analysed 201 patients who underwent curative surgery for CRC. We investigated the relationship between the expression of Wnt and ß-catenin proteins and prognosis using immunohistochemistry. RESULTS: The high expression of Wnt1 correlated with high expression of nuclear and cytoplasmic ß-catenin (p=0.0004, p=0.02). The high expression of Wnt5a also correlated with high expression of membrane ß-catenin (p=0.03). In multivariate analysis, lymph node metastasis (p=0.046) and high expression of nuclear ß-catenin (p=0.04) were independent prognostic factors for survival. CONCLUSION: The expression of nuclear ß-catenin is a useful predictive marker in CRC. It is suggested that Wnt1 may be the main activator of the ß-catenin signaling pathway and that Wnt5a may stabilize adherens junctions, thereby suppressing the epithelial-mesenchymal transition.