Beta-Catenin is a member of catenin family together with alpha and gamma catenin. It mediates cell-cell adhesion with cadherins and it is key regulatory protein in signaling through the WNT pathway. Beta catenin has a role in cellular proliferation, differentiation and development. Mutations in beta catenin gene (CTNNB1) leads accumulation of the beta catenin protein in cytoplasm and nucleus in different type of tumors eg. endometrial carcinoma and desmoid tumors. This antibody is useful in differentiation diagnostic of tumors.