[Effect of hypoglycosylated E-cadherins on proliferation and invasiveness of tongue squamous cell carcinoma].

Purpose: To investigate the effect of N-glycosylated E-cadherins on proliferation and invasiveness of tongue squamous cell carcinoma CAL 27 cells, and to study the effect of hypoglycosylation of E-cadherins on the stability of adherens junctions (AJs) mediated by E-cadherins.

Methods: Human tongue squamous cell carcinoma CAL 27 cells were respectively transfected with the plasmids encoding either hypoglycosylated or wild-type E-cadherins with FLAG as tags. Western blot of FLAG was used to detect the expression of exogenous E-cadherins in the transfected cells after 48 hours. The cell proliferation counting, monolayer cell scratch wound healing and in vitro cell invasiveness assays were performed to evaluate the proliferation and invasiveness of cells. Immunoprecipitation experiments were used to assay the quantity of α-catenins, β-catenins, γ-catenins and vinculins linked with the cytosolic tails of E-cadherins. All statistical analysis were performed using SPSS 17.0 software package.

Results: The expression of exogenous E-cadherins was detected in transfected CAL 27 cells by Western blot. Cell proliferation counting assay revealed that hypoglycosylated E-cadherins significantly inhibited proliferation of CAL 27 cells, compared with wild-type E-cadherins. The monolayer cell scratch wound healing and in vitro cell invasiveness assays indicated that hypoglycosylated E-cadherins also significantly restrained both invasiveness of CAL 27 cells, compared with wild-type E-cadherins. The immunoprecipitation experiments demonstrated that hypoglycosylated E-cadherins exhibited an increased association with α-catenins, β-catenins, and γ-catenins and vinculins.

Conclusions: Compared with wild-type E-cadherins, hypoglycosylated E-cadherins can significantly suppress proliferation and invasiveness of tongue squamous cell carcinoma CAL 27 cells, and the mechanism was that hypoglycosylated E-cadherins can induce more stable AJs than wild-type E-cadherin. Supported by Scientific Research Foundation for the Returned Oversea Chinese Scholars, State Ministry of Education of China and Shandong Provincial Award Foundation for Excellent Middle- and Young-Aged Scientists (BS2010YY021).