B Cells Infiltration Potentially Responded Better to Systemic Corticoids in Oral Lichen Planus and Oral Lichenoid Lesions.

Oral lichen planus (OLP) and oral lichenoid lesion (OLL) are chronic inflammatory diseases involving the oral mucosa. B cells infiltration in OLP and OLL, however, little is known about these cells in OLP and OLL. To analyze the function and infiltrating features of B lymphocytes in OLP and OLL, and to preliminarily evaluate their correlation with clinical outcomes. Tissue samples were collected from OLP, OLL, and healthy mucosa. The phenotypes and amounts of B cells in tissues were analyzed by single-cell sequencing. Their proportion and infiltrating features in tissues were examined by immunohistochemistry and immunofluorescence. With the systemic medication of corticoids, the correlation between B cells infiltrating characteristics and the clinical outcomes were evaluated. A quantified proportion increase of B cells was shown in both OLP and OLL. B cells in OLP demonstrated heightened activation and enhanced regulation in immune response. A cohort of 100 patients with OLP/OLL and 13 healthy controls were examined to investigate the B cells infiltration pattern. B cells were distributed in the superficial layer of lamina propria in 92.9% and 41.9% of OLP and OLL, respectively(P < 0.01); focally distributed in 25.0% and 62.9% of OLP and OLL, respectively(P < 0.01). With the systemic medication of corticoids, the cases with B cell infiltration (B+) in OLP and OLL groups showed a statistically significant reduction in REU scores before and after treatment (P < 0.01). B cells are widely present in OLP and OLL, and B cell infiltration in OLP and OLL are related to the better therapeutic effect of oral corticoids.

Research progress on oral lichenoid drug reactions / 口腔疾病防治

@#Oral lichenoid drug reactions (OLDRs) are inflammatory reactions of the oral mucosa caused by the use of specific drugs in sensitive individuals and are classified as oral lichenoid lesions (OLLs). Its clinical and pathological manifestations do not have significant specificity compared to other types of OLL. Various types of drugs have been reported to induce OLDR, including antihypertensive drugs, nonsteroidal anti-inflammatory drugs, hypoglycemic drugs, antipsychotics, and immunosuppressants, among other drugs. Apart from local or systemic administrate glucocorticoids, the most effective treatment measure is to stop using suspicious drugs. Most patients can achieve significant relief from mucosal ulcers and erosion, but white lines may still remain. OLDR has been widely reported in the literature. However, due to a lack of systematic understanding, we do not have a recognized standard for the diagnosis and treatment of this disease. There are still doubts about the causal relationship between related drugs and oral lichen-like lesions. In response to the abovementioned problems, we searched the literature on drug-related oral lichen planus and lichen-like lesions at home and abroad over the past 20 years, most of which were case reports and only a few of which were case-control studies. This article describes the current research status of lichenoid lesions from four perspectives: concepts, suspicious drugs, clinical and pathological manifestations, and treatment prognosis. We hope to provide a theoretical reference for the prevention, diagnosis, and clinical treatment of related lichenoid lesions. A literature review demonstrated that there are still many unclear issues related to the etiology, pathogenesis, clinical diagnosis and treatment, treatment prognosis, and other aspects of this disease, and further clinical and basic research is needed for in-depth exploration.

TRIM21 promotes inflammation by ubiquitylating NF-κB in T cells of oral lichen planus.

BACKGROUND: Oral lichen planus (OLP) is a mucocutaneous inflammatory disease affecting 1% general population. Tripartite motif-containing protein 21 (TRIM21) shows a significant role in OLP. This study aimed to explore the function and mechanism of TRIM21 in T cells of OLP. METHODS: Differential gene expression profile in OLP versus healthy controls (HCs) was constructed by RNA sequencing. Protein expression level and infiltration sites of TRIM21 in OLP were detected by immunoblot, immunohistochemistry, and immunofluorescence. Expression of proinflammatory cytokines and chemokines including IL-6, TNF-α, ICAM1, CXCL1, CXCL8, CXCL9, and CXCL11 in CD3+ TRIM21hi T cells were measured by quantitative real-time polymerase chain reaction analysis. Downstream pathways and substrates of TRIM21 were explored by immunoblot and immunoprecipitation. Whether TRIM21 ubiquitination its substrate and ubiquitination form were tested by ubiquitination assay in vitro. RESULTS: Compared with HCs, TRIM21 exhibited a higher level in OLP, which expressed mainly in CD3+ T lymphocytes in OLP tissues. Overexpressed TRIM21 enhanced the expression of IL-6, TNF-α, CXCL1, CXCL8, CXCL9, and CXCL11 in CD3+ T cell line through ubiquitinating nuclear factor-κB (NF-κB) via a lysine 63 (K63) linkage, which eventually activating NF-κB signaling pathway. CONCLUSIONS: In OLP, TRIM21 promoted inflammation through ubiquitylating NF-κB and activating NF-κB signaling pathway.

p53 performs an essential role in mediating the oncogenic stimulus triggered by loss of expression of neurofibromatosis type 2 during in vitro tumor progression.

The loss of the tumor suppressor neurofibromatosis type 2 gene, encoding merlin, has been considered to be a fundamental event during the malignant progression of various cell types. However, a consensus for the mainstream mechanism, by which merlin deficiency contributes to uncontrolled cellular proliferation, has not been reached. The present study aimed to determine whether silencing of merlin using lentivirus-based short hairpin RNA potentiates cellular proliferation and cell cycle progression in human colon carcinoma HCT116 cell lines, expressing p53. The present results demonstrated that merlin knockdown contributed to cellular proliferation and G1/S cell cycle progression to a greater extent in HCT116 cells wide-type for p53 (p53wt) compared with p53-null (p53-/-) cells. This was supported by overexpression experiments which demonstrated a significant inhibitory effect of excess merlin on cellular proliferation only in HCT116 p53wt cells. In order to investigate the underlying mechanisms of action, the expression of p53-involved G1/S transition genes was evaluated by western blot analysis. For HCT116 p53wt cells, merlin loss suppressed p53 expression, and therefore the dysregulation of cell cycle regulatory proteins, including p21, cyclin D1/cyclin-dependent kinase (CDK)4 and cyclin E1/CDK2 complexes. However, merlin knockdowns had no impact on the expression of any of the aforementioned molecules in p53-/- cells, indicating that lack of merlin resulted in G1/S cell cycle progression, and thereby uncontrolled cellular proliferation mainly via the regulation of p53-mediated pathways. Taken together, it was proposed that p53 performs an essential role in mediating the oncogenic stimulus triggered by merlin loss, and p53 is a molecule that should be investigated for its potential in targeted drug therapy for merlin-deficient malignancies.

Genetic and epigenetic patterns in patients with the head-and-neck paragangliomas associate with differential clinical characteristics.

PURPOSE: In addition to genetic alterations, the importance of a CpG island methylator phenotype, characterized by methylation of multiple tumour-suppressor genes (TSGs), has been acknowledged in many cancer types. This study was done to determine the impact of genetic and epigenetic patterns on the clinical characteristics of the head and neck paragangliomas (HNPGLs). METHODS: The retrospective study examined a series of 37 patients with HNPGLs who underwent surgical resection between 2010 and 2015. The mutations in the succinate dehydrogenase (SDH) genes were detected using direct DNA sequencing. Aberrant hypermethylation of the CpG islands of a panel of ten TSGs was also analysed using methylation-specific PCR. RESULTS: Direct sequencing demonstrated the presence of germline SDH mutations in ten HNPGLs. Comparisons of clinical features between mutated and non-mutated HNPGLs established an association of SDH mutations with progressive phenotypes, including an earlier formation, multiple lesions, or malignancy. There was also a significant correlation between the presence of SDH mutations and the number of TSGs methylated in HNPGLs. The SDH-related tumours were therefore more likely to suffer from a CpG island methylator phenotype. Four differentially methylated TSGs in mutated tumours vs non-mutated counterparts were identified with inefficient expression through Real-Time PCR analysis. CONCLUSIONS: Our results suggested that epigenetic inactivation on multiple TSGs may serve as a key mechanism for the progressive behaviors of SDH-mutated HNPGLs. Thus, an interplay between genetic status, epigenetic alterations, and clinical features might be established in the disease.