Function

 Beta-catenin is an adherens junction protein. Beta-Catenin is a multifunctional protein related to the adherens junction and to signal transduction.

 Beta-catenin is a key molecule of cell proliferation. Its role is central to epithelial architecture, regulating the polarity of cells and tissues.

 Beta-catenin (CTNNB1) (MIM.116806) and plakoglobin are substrates for tyrosine phosphorylation following EGF stimulation of cells.

Features

 cadherin-catenin complex
 beta-catenin/APC pathway

Targets - Ligands

 Wnt

Pathology

 somatic mutations in tumors

• somatic mutations in colorectal adenocarcinoma
• somatic mutations in hepatoblastoma
• somatic mutations in endometrioid ovarian carcinoma
• somatic mutations in medulloblastoma
• somatic mutations in deep desmoid fibromatosis (deep desmoid tumor)
• somatic mutations in pilomatricoma (pilomatrixoma) (MIM.116806) (#11472567#)
• somatic mutations in adenoid cystic carcinoma (#15195113#)
• somatic mutations in pancreatic solid-pseudopapillary tumor (83%) (#11731417#)
• somatic mutations in pancreatoblastoma (#11696422#)
• somatic mutations in Wilms tumor (#10463574#, #11103785#)
• missense mutations in classic pulmonary blastoma (#15223963#)
• somatic mutations in adamantinomatous craniopharyngioma
• somatic mutations in calcifying odontogenic cysts (#14578169#)
• somatic mutations in nasopharyngeal juvenile angiofibroma (#11238055#)
• somatic mutations in sporadic fundic gland polyps (#11238048#)
• somatic mutations in poorly differentiated (25%) and undifferentiated thyroid carcinomas (21.4%) (#11238046#)
• somatic mutations in low-stage hepatocellular carcinoma negative for hepatitis B virus

 promoter swapping

• promoter swapping between the genes for zinc finger protein PLAG1 and beta-catenin CTNNB1 in pleiomorphic adenoma with t(3;8)(p21;q12) translocations

Diagnostic immunochemistry

 desmoid fibromatosis vs low-grade fibromyxoid sarcoma differential diagnosis

• beta-catenin expression in desmoid fibromatosis / negative in low-grade fibromyxoid sarcoma

References

 Harris TJ, Peifer M. Decisions, decisions: beta-catenin chooses between adhesion and transcription. Trends Cell Biol. 2005 May;15(5):234-7. PMID: #15866026#

 Bhattacharya B, Dilworth HP, Iacobuzio-Donahue C, Ricci F, Weber K, Furlong MA, Fisher C, Montgomery E. Nuclear beta-Catenin Expression Distinguishes Deep Fibromatosis From Other Benign and Malignant Fibroblastic and Myofibroblastic Lesions. Am J Surg Pathol. 2005 May;29(5):653-659. PMID: #15832090#

 Bienz M. beta-Catenin: A Pivot between Cell Adhesion and Wnt Signalling. Curr Biol. 2005 Jan 26;15(2):R64-7. PMID: #15668160#

 Moon RT, Kohn AD, Ferrari GV, Kaykas A. WNT and beta-catenin signalling: diseases and therapies. Nat Rev Genet. 2004 Sep;5(9):691-701. PMID: #15372092#