Up-regulation of Wnt-1 and beta-catenin production in patients with advanced metastatic prostate carcinoma: potential pathogenetic and prognostic implications

BACKGROUND Wnt-1 and β-catenin expression levels play an important role in several malignancies. The authors determined the level of production of Wnt-1 and β-catenin in normal and malignant human prostate carcinoma cell lines. Surgical pathology specimens from primary prostatic adenocarcinoma, lymph node metastases, and skeletal metastases were used to establish a correlation between the level of Wnt-1/β-catenin expression, Gleason score, serum prostate-specific antigen (PSA) status, and androgen receptor (AR) status. METHODS Immunohistochemical analysis was used to investigate the expression of Wnt-1 and β-catenin in human prostate carcinoma cell lines and in paraffin embedded sections of archival samples from 67 patients with prostate carcinoma. Comparison was made with the expression of tumoral AR and lymph node and skeletal metastases. These results were used to establish a correlation with the clinicopathologic status of patients with prostate carcinoma. RESULTS Levels of both Wnt-1 and β-catenin were low in normal prostate cells and were expressed highly in human prostate carcinoma cell lines. Wnt-1 and cytoplasmic/nuclear β-catenin expression was observed in 52% and 34%, respectively, of primary prostate carcinoma specimens. High levels of expression of Wnt-1 and β-catenin were seen in 77% of lymph node metastases and in 85% of skeletal metastases. These increased levels of expression were related directly to the Gleason score and to serum PSA levels in these patients. Maximum levels of Wnt-1 and β-catenin production were observed in skeletal metastases, whereas normal prostatic tissue failed to exhibit any detectable nuclear staining for β-catenin. CONCLUSIONS High levels of Wnt-1 and β-catenin expression were associated with advanced, metastatic, hormone-refractory prostate carcinoma, in which they can serve as markers of disease progression. Cancer 2004. © 2004 American Cancer Society.