Oral and pharyngeal cancer is the sixth most common cancer worldwide, the 5-year survival rate has not yet increased. A key factor in rates not having improved is the lack of early detection. This study was undertaken to estimate the diagnostic accuracy of brush biopsy with DNA-image cytometry (a noninvasive method) for potentially malignant oral disorders compared with tissue biopsy pathology in China. Exfoliative cells were obtained using a cytobrush cell collector from oral mucosa of 52 subjects, followed by scalpel biopsy from the same region. Nuclear DNA contents (ploidy) were measured after Feulgen restaining, using an automated DNA image cytometer. Exfoliative cytology with DNA-image cytometry and histopathological diagnosis were performed separately at different institutions. Histological investigation was considered the gold standard. We reported that the sensitivity of DNA aneuploidy for the detection of cancer cells in potentially malignant oral disorders was 86.36 %, its specificity was 90.00 %, its positive predictive value was 86.36 %, and its negative predictive value was 90.00 %. Brush biopsy with DNA-image cytometry is a useful method for monitoring potentially malignant oral disorders.

Oral lichen planus (OLP) is a localized autoimmune disease of the oral mucosa, with an incidence of up to 2%. Although corticosteroids are the first-line treatment, they cause several adverse effects. Quercetin, a naturally occurring compound, has fewer side-effects and provides long-term benefits. Besides, it has powerful anti‑inflammatory activities. Here, we combined network pharmacology with experimental verification to predict and verify the key targets of quercetin against OLP. First, 66 quercetin-OLP common targets were analyzed from various databases. The protein–protein interaction (PPI) network was constructed. Topology analysis and MCODE cluster analysis of common targets were conducted to identify 12 key targets including TP53, IL-6 and IFN-γ and their connections. Gene functions and key signaling pathways, including reactive oxygen species metabolism, IL-17 pathway and AGE-RAGE pathway, were enriched by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Then, in vitro experiments showed that quercetin interfered with Th1/Th2 balance by acting on IL-6 and IFN-γ to modulate the immune system in treating OLP. Quercetin considerably affected the apoptosis and migration of T lymphocytes in OLP patients. Our study reveals the potential therapeutic targets and signaling pathways of quercetin associated with OLP, and establishes the groundwork for future clinical applications.

Oral lichen planus (OLP) is suggested to be a T cell-mediated chronic inflammatory oral mucosal disease. Gene expressed in the oligodendrocyte lineage-myelin basic proteins (Golli-MBP) and stromal interaction molecule 1 (STIM1) are important in the activation and function of T lymphocytes. This study aimed to analyze and compare the expression of Golli-MBP and STIM1 between OLP patients and healthy controls and to analyze the level of intracellular Ca(2+), which is involved in lymphocyte activation. The Ca(2+) fluorescent probe, Fluo-3/AM, was used to test the level of intracellular Ca(2+) in patients with OLP and healthy controls peripheral blood lymphocytes. Golli-MBP and STIM1 mRNA and protein levels were analyzed using quantitative real-time PCR and Western blot, respectively. Following lymphocyte activation, the intracellular Ca(2+) in OLP patients was markedly lower than that in the control group (P < 0.001). In OLP patients, the expression of Golli-MBP mRNA and protein was significantly upregulated compared to those of the control group (P < 0.001). Similarly, OLP patients showed markedly upregulated levels of STIM1 mRNA expression (P < 0.01) and protein compared to healthy controls. The intracellular Ca(2+) of OLP patients was markedly lower than that of healthy controls. This evidence may indicate that Ca(2+) signaling pathways in OLP patients are abnormal. The overexpression of Golli-MBP and STIM1 may play a role in the pathogenesis of OLP.

Oral lichen planus (OLP) is generally accepted to be a T cell-mediated chronic inflammatory disease with an unclear pathogenesis. There have been numerous studies on the proliferation and apoptosis of T cells in situ. In contrast, research on the proliferation and apoptosis of peripheral blood mononuclear cells (PBMCs) in patients with OLP is rare. The aim of the present study was to investigate the proliferation and apoptosis of PBMCs in patients with OLP. PBMCs were isolated from 20 patients with reticular OLP, 20 patients with atrophic-erosive OLP, and 20 healthy volunteers. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl-2,5-tetrazolium bromide assays were performed to investigate the proliferation of PBMCs, and caspase-3 colorimetric assays were performed to investigate the apoptosis of PBMCs. The proliferation rate of PBMCs in atrophic-erosive OLP subjects was significantly higher than that in both healthy (P < 0.05) and reticular OLP (P < 0.05) subjects. In contrast, the proliferation rate of PBMCs in reticular OLP subjects was significantly lower than that in healthy subjects (P < 0.05). The apoptosis rates of PBMCs in OLP subjects (P < 0.05) and atrophic-erosive OLP subjects (P < 0.05) were significantly lower than the apoptosis rate in the healthy group. Our findings reinforce the view that T cell-mediated immune responses play a critical role in the pathogenesis of OLP. It can reasonably be concluded that these abnormalities are linked to the presence of inflammatory infiltrates.