[Significance of Smad4, Smad7 and Caveolin-1 expression in oral mucosa carcinogenesis of Wistar rats].

PURPOSE: To investigate the expression of Smad4, Smad7 and Caveolin-1 in the process of carcinogenesis of oral mucosa in Wistar rats, and to understand the changes of TGF-β/Smad signaling pathway and Caveolin-1 in oral cancer.

METHODS: Palatal mucosal carcinogenesis specimens of Wistar rats were obtained from School of Stomatology, Zhengzhou University, which included 5 samples of normal mucosa, 10 samples of simple hyperplasia mucosa, 6 samples of mild mucosal dysplasia, 7 samples of moderate mucosal dysplasia, 13 samples of mucosa severe mucosal dysplasia, and 28 samples of oral cancer tissue. The expression of Smad4, Smad7 and Caveolin-1 was detected by immunohistochemistry. SPSS15.0 software package was used for statistical analysis.

RESULTS: The expression of Smad4 decreased in normal and hyperplastic epithelia, dysplasticepithelia and oral cancer gradually, the difference of the expression among the three groups was significant (P<0.05). The expression of Smad7 and Caveolin-1 increased in normal and hyperplastic epithelia, dysplasticepithelia and oral cancer gradually, respectively; the difference of the expression among the 3 groups was significant (P<0.05). Spearman correlation analysis showed that Smad4 was negatively correlated with Smad7, Smad4 was negatively correlated with caveolin-1, Smad7 was positively correlated with Caveolin-1 (P<0.05).

CONCLUSIONS: Synergistic effects may exist among Smad4, Smad7 and caveolin-1 in carcinogenesis of oral cancer.