Expression of caspase-8, receptor interacting protein and nuclear factor-kappaBp65 in oral lichen planus

Abstract

To investigate the expressions of caspase-8, receptor interacting protein (RIP) and nuclear factor (NF)-kappaBp65 in oral lichen planus (OLP) and their relationship with cell apoptosis. Immunohistochemical technique with SP method was used to detect the expressions of caspase-8, RIP and NF-kappaBp65 in 30 OLP cases and 15 normal oral mucosa specimens. Terminal deoxynucleotidyl transferase-mediated nucleotide shift enzyme (TdT) mediated d-UTP end labeling (TUNEL) was used for detecting the cell apoptotic index (AI) in 15 OLP cases and 5 nomal oral mucosa specimens. Compared with the control group, the AI of epithelial cells (6.76 +/- 2.32) increased and the AI of lymphocytes (1.75 +/- 0.74)decreased in OLP (P < 0.01). The positive rate of caspase-8, RIP and NF-kappaBp65 of epithelial cells were 97% (29/30), 87% (26/30) and 93% (28/30) respectively, significantly higher in OLP than in normal control (P < 0.05). The positive rate of caspase-8, RIP and NF-kappaBp65 of lymphocytes were 100% (30/30, 90% (27/30) and 80% (24/30) respectively, significantly higher in OLP than in normal control (P < 0.01). A positive correlation was also observed between NF-kappaBp65 expression of lymphocytes and AI of epithelial cells. Accelerated apoptosis of the keratinocytes and inhibition of lymphocyte apoptosis may coexist and contribute to the formation and progression of OLP. The over expression of caspase-8, RIP and NF-kappaBp65 in OLP may play a role in the pathogenesis of OLP.