[The expression and changes of apoptosis protein Bcl-2 and Bax in oral lichen planus].

PURPOSE: To analyze the changes in epithelial cells, and observe the expression of Bcl-2, Bax and apoptosis in oral lichen planus.

METHODS: Thirty five OLP patients and 10 healthy volunteers were enrolled in this study. Immunohistochemical S-ABC was used to detect Bcl-2 and Bax expression in OLP group and control group. TUNEL and flow cytometry were used to study the apoptosis of the epithelial cells. Transmission electron microscope (TEM) was used to observe the changes of ultra-microstructure of oral membrane of OLP. The data was analyzed with SPSS 17.0 software package.

RESULTS: The expression of Bcl-2 in OLP group was not significantly different from control group (P>0.05), but the expression was remarkably elevated in lymphocyte infiltration zone. Bax positive expression rate and intensity in OLP group significantly increased compared with the control group (P<0.01). The apoptosis index was remarkably increased in the epithelial cells in OLP group compared with the control group (P<0.01), which was consistent with the result of flow cytometry(the apoptotic percentage of the epithelial cells in OLP group was significantly higher than the control group). TEM showed that the apoptotic cells of mucous membrane of OLP increased, with chromatin margination, and apoptotic body.

CONCLUSIONS: The ultra-microstructure change in the lesional tissue, increased apoptotic cells, elevated Bcl-2 in lymphocyte infiltration zone and elevated Bax in epithelial basement keratin suggest that apoptosis may be related to the carcinogenesis and development of OLP.