Analysis of β-catenin expression and exon 3 mutations in pediatric sporadic aggressive fibromatosis.

Abstract

Aggressive fibromatosis is a benign tumor with a high recurrence rate after surgical resection, particularly in children. Abnormal regulation of β-catenin in the presence or absence of a change of genotype has been identified in adult sporadic aggressive fibromatosis. However, the status of β-catenin expression and mutation remains unclear in pediatric patients. The present study was designed to analyze the expression and mutation status of β-catenin in pediatric aggressive fibromatosis. B-catenin expression was analyzed by immunohistochemistry in 32 samples from pediatric patients with aggressive fibromatosis (21 recurrent cases and 11 primary-onset cases) and 15 control subjects. Somatic point mutations in β-catenin exon 3 were identified by sequencing of polymerase chain reaction products. Nuclear expression of β-catenin was detected in 94% (30/32) of aggressive fibromatosis samples and 13% (2/15) of control samples (P < 0.001). Mutations in exon 3 of the β-catenin gene were identified in 78% (25/32) of aggressive fibromatosis samples (19/21 recurrent cases, 6/11 primary-onset cases; P  =  0.032). The primary mutation in the recurrent cases occurred at codon 45 (S45F), while codon 41 (T41A) was most frequently mutated in the primary-onset cases (P  =  0.002). Abnormal expression of β-catenin appears to occur frequently in pediatric aggressive fibromatosis. Muftations in exon 3 of the β-catenin gene, particularly the S45F mutation, may represent risk factors for recurrence in pediatric patients and could potentially be used as prognostic factors.

• Authors: Ning Bo, Dahui Wang, Bingbing Wu, Lian Chen, Ruixue Ma
• Journal: Pediatric and developmental pathology : the official journal of the Society for Pediatric Pathology and the Paediatric Pathology Society (Pediatr Dev Pathol) 2012 May-Jun Vol. 15 Issue 3 Pg. 173-8 ISSN: 1093-5266 [Print] United States
• PMID: 21323417 (Publication Type: Journal Article)

Chemical References

• CTNNB1 protein, human
• beta Catenin

Topics

• Adolescent
• Child
• Child, Preschool
• DNA Mutational Analysis
• Exons (genetics)
• Female
• Fibromatosis, Aggressive (genetics, metabolism)
• Humans
• Immunohistochemistry
• Male
• Point Mutation
• Reverse Transcriptase Polymerase Chain Reaction
• beta Catenin (biosynthesis, genetics)