Nuclear localization of beta-catenin and plakoglobin in primary and metastatic human colonic carcinomas, colonic adenomas, and normal colon.
Beta-catenin is a cytoskeleton-associated signaling molecule shown to be elevated in various carcinomas but mostly in colon cancer owing to its impaired degradation. In contrast, its close homologue plakoglobin was shown to suppress the tumorigenicity of certain tumor cells. In the present study, we have used a semiquantitative immunohistochemical approach to evaluate the extent of nuclear localization of beta-catenin in human colonic adenocarcinomas and adenomas and compared it to the distribution of plakoglobin in the same tissues. We show that beta-catenin accumulates in the nuclei of the epithelium of primary and metastatic colonic adenocarcinoma as well as in colonic adenomas. In contrast, nuclear plakoglobin levels in these tissues were low, even compared to those found in epithelial cells of normal colon. These results support the view that the increase in beta-catenin levels in colon cancer cells occurs early in the tumorigenic process, leading to its nuclear localization, not only in invasive adenocarcinoma, but also in colonic adenoma with mild dysplasia.
Lifschitz-Mercer
B
B
The Institute of Pathology, Sourasky Medical Center, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
Amitai
R
R
Maymon
B B
BB
Shechtman
L
L
Czernobilsky
B
B
Leider-Trejo
L
L
Ben-Ze'ev
A
A
Geiger
B
B
D000230:Adenocarcinoma / Q000378:metabolism*; D000236:Adenoma / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D003106:Colon / Q000378:metabolism; D003110:Colonic Neoplasms / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D051180:Desmoplakins; D004848:Epithelium / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000556:secondary; D008207:Lymphatic Metastasis; D021381:Protein Transport / Q000502:physiology; D015534:Trans-Activators / Q000378:metabolism*; D051176:beta Catenin; D051185:gamma Catenin
C495270:CTNNB1 protein, human; D003598:Cytoskeletal Proteins; D051180:Desmoplakins; D015534:Trans-Activators; D051176:beta Catenin; D051185:gamma Catenin