Nuclear localization of beta-catenin is correlated with the expression of cyclin D1 in endometrial carcinomas.

Background: β-catenin has recently been reported to act as a cell growth promoter through cyclin Dl transcription. However, the correlation between β-catenin and cyclin Dl expressions is not fully understood in endometrial tissues. Materials and Methods: Immunohistochemical expression of β-catenin was examined in normal endometria (32 cases) and endometrial carcinomas (82 cases), and its expression was compared with that of cyclins (Dl, E, A, B1). Results: Sporadic nuclear staining of β-catenin and cyclins was observed from proliferative phase to early secretory phase endometria, however, spacial correlations between β-catenin and cyclins were not evident. In endometrial carcinomas, positivity for nuclear β-catenin and cyclins increased compared to the normal endometria. Topologically, the cyclin D1-positive cells were frequently found in nuclear β-catenin-positive cells. In addition, Spearman's rank correlation analysis revealed that the nuclear expression of β-catenin correlated positively with that of cyclin Dl (p<0.0001). Conclusion: The β-catenin-cyclin Dl pathway might be involved in the growth of endometrial carcinomas.