Expression and tyrosine phosphorylation of E-cadherin, beta- and gamma-catenin, and epidermal growth factor receptor in cervical cancer cells.
OBJECTIVE
The cadherin/catenin adhesion complex is fundamentally involved in epithelial cancer invasion and metastasis. Much evidence suggesting that epidermal growth factor (EGF) induced the scattering and invasion of cancer cells, probably by affecting E-cadherin function, has been reported. The present study aimed to confirm the hypothesis that EGF/epidermal growth factor receptor (EGFR) was related with the E-cadherin adhesion system in cervical cancer cells and that EGF might induce tyrosine phosphorylation of beta- and gamma-catenin.


METHODS
Cervical cancer cells were treated for different time durations with 30 ng/ml of EGF. Alteration of the cell morphology was examined by light microscopy and the expression of E-cadherin, beta-catenin, gamma-catenin, EGFR, and activated EGFR was assayed using Western blotting. Tyrosine phosphorylation of beta- and gamma-catenin was also examined using immunoprecipitation.


RESULTS
E-cadherin and EGFR were expressed in CaSki, HT-3, and ME-180 cell lines, which showed epithelial contact growth. The expression of E-cadherin and beta- and gamma-catenin did not change after treatment with EGF. The expression of EGFR decreased and activated EGFR expression increased in 30 min and then decreased subsequently. The simultaneous expression of activated EGFR and tyrosine phosphorylation of beta- and gamma-catenin was found.


CONCLUSIONS
EGF-induced scattering of the E-cadherin-positive cervical cancer cells might be the result of tyrosine phosphorylation of the beta- and gamma-catenin. Phosphorylation of the beta- and gamma-catenin may hamper the adhesive function of the E-cadherin-catenin complex.
Moon
H S
HS
Department of Obstetrics and Gynecology, Ewha Womans University, Seoul, 158-710, Korea.
Choi
E A
EA
Park
H Y
HY
Choi
J Y
JY
Chung
H W
HW
Kim
J I
JI
Park
W I
WI
D015153:Blotting, Western; D015820:Cadherins / Q000096:biosynthesis / Q000378:metabolism*; D002448:Cell Adhesion / Q000187:drug effects; D003598:Cytoskeletal Proteins / Q000096:biosynthesis / Q000378:metabolism*; D051180:Desmoplakins; D004815:Epidermal Growth Factor / Q000494:pharmacology; D066246:ErbB Receptors / Q000096:biosynthesis / Q000378:metabolism*; D005260:Female; D006801:Humans; D010766:Phosphorylation; D011233:Precipitin Tests; D015534:Trans-Activators; D014407:Tumor Cells, Cultured / Q000187:drug effects; D014443:Tyrosine / Q000378:metabolism; D002583:Uterine Cervical Neoplasms / Q000378:metabolism* / Q000473:pathology; D051176:beta Catenin; D051185:gamma Catenin
C495270:CTNNB1 protein, human; D015820:Cadherins; D003598:Cytoskeletal Proteins; D051180:Desmoplakins; C495292:JUP protein, human; D015534:Trans-Activators; D051176:beta Catenin; D051185:gamma Catenin; D014443:Tyrosine; D004815:Epidermal Growth Factor; D066246:ErbB Receptors