Immunohistochemically, there was a statistically significant correlation between widespread nuclear expression of beta-catenin and overexpression of matrix metalloproteinase-7 (P < .01 in extra-abdominal desmoid, Fisher test).
Taken together, we propose that TGF-beta is a modulator of beta-Catenin levels in tumoral fibroblasts and non-tumoral fibroblasts, despite the oncogenic mutations already present in this gene in tumoral fibroblasts of desmoid tumors.
Tumor specimens from 14 patients surgically treated for aggressive fibromatosis (6 familial adenomatous polyposis and 8 sporadic cases), analyzed for adenomatous polyposis coli (APC) and CTNNB1 (beta-catenin) mutations, were further investigated for beta-catenin, cyclooxygenase-2 (COX-2), platelet-derived growth factor (PDGF) receptor alpha (PDGFRA)/PDGF receptor beta (PDGFRB), their cognate ligands (PDGFA and PDGFB), and KIT using a comprehensive immunohistochemical, biochemical, molecular, and cytogenetic approach.
Taken together, we propose that TGF-beta is a modulator of beta-Catenin levels in tumoral fibroblasts and non-tumoral fibroblasts, despite the oncogenic mutations already present in this gene in tumoral fibroblasts of desmoid tumors.
While tumours from the colorectum and upper gastrointestinal tract usually retain one to two and three to four beta-catenin degradation repeats, respectively, most desmoids preferentially retain two repeats (P < 0.001, chi2 test).
The aim of this study was to determine the specificity and sensitivity of these 3 most common beta-catenin mutations in the diagnosis of desmoid-type fibromatosis using paraffin-embedded material.
SAMD9 is expressed at a lower level in a variety of neoplasms associated with beta-catenin stabilization, such as aggressive fibromatosis, breast, and colon cancers.
To investigate whether this hypothesis could be extended to other Wnt-dependent tumor types, we searched for WT1 mutations and studied WT1 expression in beta-catenin mutant desmoid tumors.
The aim of this study is to investigate the immunohistochemical profile and the involvement of the beta-catenin pathway in desmoplastic fibroma as it is known in desmoid-type fibromatosis.
Accumulation of altered beta-catenin associated with a somatic heterozygous activating mutation in codon 41 was detected in the typical desmoid-type fibromatosis and at the ossifying focus.
FAP results from germline adenomatous polyposis coli (APC) gene mutations and desmoids arise following biallelic APC mutation, with one change usually occurring distal to the second beta-catenin binding/degradation repeat of the gene (3' to codon 1399).
The demonstration of mutations in two mediators in the Wnt-APC-beta-catenin pathway implicates beta-catenin stabilization as the key factor in the pathogenesis of aggressive fibromatosis.