Frequent loss of the AXIN1 locus but absence of AXIN1 gene mutations in adenocarcinomas of the gastro-oesophageal junction with nuclear beta-catenin expression.

ABSTRACT: Up to 60% of gastro-oesophageal junction (GEJ) adenocarcinomas show nuclear beta-catenin expression, pointing to activated T-cell factor (TCF)/beta-catenin-driven gene transcription. We demonstrate in five human GEJ adenocarcinoma cell lines that nuclear beta-catenin expression indeed correlates with enhanced TCF-mediated transcription of a reporter gene. In several tumour types, TCF/beta-catenin activation is caused by mutations in either adenomatous polyposis coli (APC), beta-catenin exon 3, AXIN1, AXIN2 or beta-transducin repeat-containing protein (beta-TrCP). In GEJ adenocarcinomas, very few APC and beta-catenin mutations have been found. Therefore, the mechanism of Wnt pathway activation remains unclear. In the present study, we did not find AXIN1 gene mutations in 17 GEJ tumours with

SUBMITTER: Koppert LB 

PROVIDER: S-EPMC3215949 | biostudies-literature | 2004 Feb

REPOSITORIES: biostudies-literature