title: The expression and mutation of β-catenin in colorectal traditional serrated adenomas.
abstract: BACKGROUND
  Exon 3 mutation of β-catenin is associated with the carcinogenesis.
  
  
  OBJECTIVE
  In this study we aimed to detect the expression of exon 3 mutations of β-catenin in colorectal TSA, TA/VTA, and CRC.
  
  
  METHODS
  Immunohistochemistry staining for β-catenin was performed for 30 TSA, 20 tubular adenomas (TA)/villous tubular adenomas (VTA), and 21 colorectal carcinoma (CRC) cases. DNA sequencing of the exon 3 of β-catenin gene was performed for 8 TSA cases, 6 TA cases, 5 VTA cases, and 10 CRC cases with positive staining in the nuclei and cytoplasm.
  
  
  METHODS
  A Fisher exact test and chi-square test were used to analyze the differentiations of the expression of β-catenin in TSA, TA/VTA, and CRC. Results : The percentages of β-catenin expression in TSA, TA/VTA, and CRC were 76.6% (23/30), 70.0% (14/20), and 95.2% (20/21), respectively, and were significantly different among these three types of tissue specimens (χ2 = 22.805, P < 0.001). Although β-catenin expression levels in TSA were not related to it in TA/VTA, they were significantly different between TSA/TA/VTA and CRC. The degree of dysplasia was well correlated with β-catenin expression (TSA: P < 0.01; TA/VTA: P < 0.05). But β-catenin exon 3 mutations were not detected in any of these tissue specimens.
  
  
  CONCLUSIONS
  Aberrant β-catenin expression is associated with the degree of dysplasia in TSA. β-catenin likely plays an important role in the pathogenesis of colorectal TSA and conventional adenomas.
authors.affiliation: Department of Pathology, Chinese People's Liberation Army, Beijing, People's Republic of China.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Dai
authors.forename: Luping
authors.initials: L
authors.lastname: Wang
authors.forename: Liying
authors.initials: L
authors.lastname: Zhang
authors.forename: Ying
authors.initials: Y
authors.lastname: Han
authors.forename: Guangzhi
authors.initials: G
authors.lastname: Yang
authors.forename: Lin
authors.initials: L
authors.lastname: Li
mesh_terms: D000236:Adenoma / Q000473:pathology*; D015179:Colorectal Neoplasms / Q000473:pathology*; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D008853:Microscopy; D009154:Mutation; D051176:beta Catenin / Q000096:biosynthesis* / Q000235:genetics*
chemical_list: D051176:beta Catenin