Abnormalities of beta-Catenin Gene in Pilomatricomas.
- Author:
Hyun Jeong LEE
1
;
Seog Jun HA
;
Jung Soo KIM
;
Seung Dong LEE
;
Jin Wou KIM
Author Information
1. Department of Dermatology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
- Publication Type:Original Article
- Keywords:
beta-Catenin;
CTNNB1;
Mutation;
Pilomatricoma
- MeSH:
Adenomatous Polyposis Coli;
Basophils;
beta Catenin*;
Cytoplasm;
Exons;
Gene Silencing;
Lymphocytes;
Mutation, Missense;
Pilomatrixoma*
- From:Korean Journal of Dermatology
2002;40(1):14-18
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: beta-Catenin muations were reported to play a causal role in the development of pilomatricomas. In a recent study in Caucasians, 75% of pilomatricomas had beta-Catenin mutations. OBJECTIVE: We investigated the causal role of beta-Catenin gene mutations in pilomatricomas of Koreans. METHODS: This study included 20 formalin-fixed, paraffin-embedded pilomatricomas in Koreans. Basophilic nucleated tumor cells were microdissected and, as normal controls, infiltrating inflammatory lymphocytes were microdissected from the same histologic specimens. Sequencing analysis of exon 3 of the beta-Catenin gene (CTNNB1) was performed. Immunostaining for beta-Catenin and Lef-1 was performed by the avidin-biotin-peroxidase method. RESULTS: Sequencing analysis found missense mutations (S37Y, S37C, S33C, S33F, and S37F) in CTNNB1 in 6 samples (30%) of 20 pilomatricomas. All pilomatricomas revealed intense expression of nuclear Lef-1 and nuclear and cytoplasmic beta-Catenin. CONCLUSION: Frequencies of beta-Catenin mutations were lower in our study compared with the results in Caucasians. The immunohistochemical results suggest the abnormalities in Wnt-wingless pathway resulting in stabilization or constitutive expression of beta-Catenin, but the absence of CTNNB1 mutations in 70% of our cases suggests adenomatous polyposis coli gene inactivation, or the involvement of other components of the Wnt-wingless pathway.
