[Expressions of Fas/FasL and granzyme B in oral lichen planus and their significance].

Objective: To define the association of the expressions of Fas/FasL and granzyme B with cell apoptosis in oral lichen planus (OLP) and progression of the disease.

Method: Immunohistochemical method and TUNEL were employed to study the expressions of Fas, FasL and granzyme B and cell apoptosis in 50 OLP cases (including 20 cases of atrophic-erosive OLP and 30 nonerosive OLP cases) and 10 normal oral mucosa specimens.

Results: Compared with the control group, the OLP cases showed increased apoptotic index (AI, 95.32+/-28.99) in the epithelial layer and the decreased AI (35.12+/-9.89) in the lamina propria (P<0.05), with the apoptotic cells confined within the basal or suprabasal cell layer instead of the superficial cell layer in the control group. The positivity rates of FasL and granzyme B expression were both 68/ in the lamina propria of the OLP cases, remarkably higher than those in the normal control group (P<0.05); significantly higher rates were noted in atrophic-erosive than in nonerosive OLP cases (P<0.05).

Conclusions: The AI significantly differs between the epithelial layer and lamina propria in OLP cases, for which the expressions of Fas, FasL and granzyme B might be held responsible. The over-expressions of FasL and granzyme B are closely related to the progression of OLP.