title: Patterns of beta-catenin expression in gastric carcinoma: clinicopathological relevance and mutation analysis.
abstract: Studies on the expression of beta-catenin (beta-ct) in gastric carcinoma have provided conflicting results, and the role played by beta-ct mutations in gastric carcinogenesis remains unclear. In an attempt to clarify the aforementioned issues we undertook the retrospective study of 157 gastric carcinomas by using immunohistochemistry and molecular genetics. Reduced/absent membranous beta-ct expression was significantly associated with isolated-cell/diffuse histotype both in "pure" diffuse gastric carcinomas and in the isolated-cell/diffuse component of mixed carcinomas. Cytoplasmic and/or nuclear beta-ct expression was particularly prevalent in mixed carcinomas and was significantly associated with lymphatic vessel invasion and lymph node metastases. beta-ct mutations were not detected in any case. We conclude that the pattern of beta-ct expression is closely related to gastric carcinoma histotype. The activation of Wnt/beta-ct pathway is associated with mixed gastric carcinoma and with features of clinical aggressiveness; the mechanism(s) underlying this pathway in gastric carcinoma are not due to beta-ct mutations and remain to be elucidated.
authors.affiliation: IPATIMUP-Institute of Molecular Pathology and Immunology of the University of Porto, Portugal.
authors.forename: Sérgio
authors.initials: S
authors.lastname: Nabais
authors.forename: José Carlos
authors.initials: JC
authors.lastname: Machado
authors.forename: Carlos
authors.initials: C
authors.lastname: Lopes
authors.forename: Raquel
authors.initials: R
authors.lastname: Seruca
authors.forename: Fátima
authors.initials: F
authors.lastname: Carneiro
authors.forename: Manuel
authors.initials: M
authors.lastname: Sobrinho-Simões
mesh_terms: D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology; D003593:Cytoplasm / Q000378:metabolism / Q000473:pathology; D003598:Cytoskeletal Proteins / Q000235:genetics* / Q000378:metabolism*; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000032:analysis; D005753:Gastric Mucosa / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques; D009154:Mutation; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism*; D051176:beta Catenin
chemical_list: C495270:CTNNB1 protein, human; D003598:Cytoskeletal Proteins; D004273:DNA, Neoplasm; D015534:Trans-Activators; D051176:beta Catenin