Beta-catenin expression in human cancers.
Cell-cell adhesion in tissue is mainly regulated by homotypic interaction of cadherin molecules, which are anchored to the cytoskeleton via cytoplasmic proteins, including alpha- and beta-catenin. Although we previously demonstrated that alpha-catenin is crucial for cadherin function in vivo, little is known about the role of beta-catenin. We examined the expression of beta-catenin in human carcinoma samples along with normal tissue (esophagus, stomach, and colon) by immunostaining using our antibody for beta-catenin. Normal epithelium strongly expressed beta-catenin. However, beta-catenin expression was frequently reduced in primary tumors of the esophagus (10 of 15, 67%), stomach (9 of 19, 47%), and colon (11 of 22, 50%). From an immunoprecipitation study, we found that beta-catenin forms a complex with E-cadherin not only in the normal epithelium but also in cancerous tissues. In coexpression patterns of E-cadherin and beta-catenin, 43 (77%) of the 56 tumors showed a similar expression of both molecules, whereas the other 13 tumors (23%) showed positive staining for E-cadherin and reduced expression of beta-catenin. These findings suggest that beta-catenin forms a complex with E-cadherin in vivo and down-regulation of beta-catenin expression is associated with malignant transformation.
Department of Surgery II, Osaka University Medical School, Japan.
T
T
Takayama
H
H
Shiozaki
S
S
Shibamoto
H
H
Oka
Y
Y
Kimura
S
S
Tamura
M
M
Inoue
T
T
Monden
F
F
Ito
M
M
Monden
D000230:Adenocarcinoma / Q000737:chemistry* / Q000473:pathology; D000595:Amino Acid Sequence; D015820:Cadherins / Q000032:analysis*; D002294:Carcinoma, Squamous Cell / Q000737:chemistry*; D003110:Colonic Neoplasms / Q000737:chemistry* / Q000473:pathology; D003598:Cytoskeletal Proteins / Q000032:analysis* / Q000737:chemistry; D004938:Esophageal Neoplasms / Q000737:chemistry*; D006801:Humans; D007150:Immunohistochemistry; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000032:analysis*; D013274:Stomach Neoplasms / Q000737:chemistry*; D015534:Trans-Activators; D051176:beta Catenin
C495270:CTNNB1 protein, human; D015820:Cadherins; D003598:Cytoskeletal Proteins; D009363:Neoplasm Proteins; D015534:Trans-Activators; D051176:beta Catenin