Microsatellite analysis of APC and immunoexpression of beta catenin did not provide significant pathological or prognostic information in this cohort of nephroblastomas.
This overlap in mutation pattern of WT1 and beta-catenin in Wilms' tumor suggests that these 2 genes may collaborate in the genesis of a subset of Wilms' tumors.
Deregulation of the Wnt signalling pathway is a key event in the development of a broad spectrum of human malignancies and mutations in beta-catenin (CTNNB1), a central component of the Wnt pathway, have been detected in 10-15% of Wilms tumors (nephroblastoma).
This study has analysed the intracellular levels and subcellular distribution of beta-catenin protein in 36 primary Wilms' tumour specimens and has correlated these results with the mutational status of the beta-catenin gene.
In addition, as the beta-catenin mutation is frequently associated with the WT1 mutation, the association of WT1 silencing with the beta-catenin mutation was also investigated. beta-catenin mutated in only one WT without WT1 silencing, suggesting that the beta-catenin mutation was not associated with the reduction of WT1 expression.
To assess the relationship of WT1 mutations vis-à-vis beta-catenin mutations in Wilms tumor, we analyzed 153 primary tumors, and 21 of 153 (14%) carried beta-catenin mutations.