Low expression of glucocorticoid receptor a in oral lichen planus correlates with activation of nuclear factor κB: a preliminary study.

BACKGROUND: Emerging evidence indicates that the interaction between glucocorticoid receptor α (GRα) and nuclear factor κB (NF-κB) is a key pathogenetic cross talk in the autoimmune and inflammatory disorders. The objective of this study was to determine the GRα expression in patients with oral lichen planus (OLP) and investigate its correlation with NF-κB in OLP.

METHODS: We compared the expression of GRα and NF-κB in oral biopsy specimens from patients with OLP(n = 32) against normal controls (n = 12) and investigated the correlation between the expression of GRα and NF-κB in OLP.

RESULTS: Immunohistochemistry showed that GRα mainly expressed in the cytoplasm of keratinocytes of basal and spinosum layer of OLP. Both real-time quantitative PCR and Western blots revealed that the mRNA and protein expression levels of GRα were decreased compared with normal controls (both P < 0.001). Conversely, those levels of nuclear factor-kappa B (NF-κB) were increased compared with normal controls (both P < 0.001). Importantly, a significant inverse correlation between the GRα and NF-κB was found (P < 0.05).

CONCLUSIONS: Our findings demonstrated that low expression of GRα in OLP correlates with activation of NF-κB, which indicates that the cross talk between GRα and NF-κB in OLP may become a new therapeutic target and represent a new approach to explore the pathogenesis of OLP.