Abnormal accumulation of collagen fibrils is a hallmark feature of oral submucous fibrosis (OSF). However, the precise characteristics and underlying mechanisms remain unclear, impeding the advancement of potential therapeutic approaches. Here, we observed that collagen I, the main component of the extracellular matrix, first accumulated in the lamina propria and subsequently in the submucosa of OSF specimens as the disease progressed. Using RNA-seq and Immunofluorescence in OSF specimens, we screened the cartilage oligomeric matrix protein (COMP) responsible for the abnormal collagen accumulation. Genetic COMP deficiency reduced arecoline-stimulated collagen I deposition significantly in vivo. In comparison, both COMP and collagen I were upregulated under arecoline stimulation in wild-type mice. Human oral buccal mucosal fibroblasts (hBMFs) also exhibited increased secretion of COMP and collagen I after stimulation in vitro. COMP knockdown in hBMFs downregulates arecoline-stimulated collagen I secretion. We further demonstrated that hBMFs present heterogeneous responses to arecoline stimulation, of which COMP-positive fibroblasts secrete more collagen I. Since COMP is a molecular bridge with Fibril-associated collagens with Interrupted Triple helices (FACIT) in the collagen network, we further screened and identified collagen XIV, a FACIT member, co-localizing with both COMP and collagen I. Collagen XIV expression increased under arecoline stimulation in wild-type mice, whereas it was hardly expressed in the Comp^-/- mice, even with under stimulation. In summary, we found that COMP may mediates abnormal collagen I deposition by functions with collagen XIV during the progression of OSF, suggesting its potential to be targeted in treating OSF.
Oral Submucous Fibrosis/pathology* ; Cartilage Oligomeric Matrix Protein/genetics* ; Animals ; Mice ; Humans ; Fibroblasts/metabolism* ; Collagen Type I/metabolism* ; Arecoline/pharmacology* ; Mouth Mucosa/metabolism* ; Cells, Cultured ; Fluorescent Antibody Technique

Hypoxemia is a common pathological state characterized by low oxygen saturation in the blood. This condition compromises mucosal barrier integrity particularly in the gut and oral cavity. However, the mechanisms underlying this association remain unclear. This study used periodontitis as a model to investigate the role of platelet activation in oral mucosal immunopathology under hypoxic conditions. Hypoxia upregulated methyltransferase-like protein 4 (METTL4) expression in platelets, resulting in N⁶-methyladenine modification of mitochondrial DNA (mtDNA). This modification impaired mitochondrial transcriptional factor A-dependent cytosolic mtDNA degradation, leading to cytosolic mtDNA accumulation. Excess cytosolic mt-DNA aberrantly activated the cGAS-STING pathway in platelets. This resulted in excessive platelet activation and neutrophil extracellular trap formation that ultimately exacerbated periodontitis. Targeting platelet METTL4 and its downstream pathways offers a potential strategy for managing oral mucosa immunopathology. Further research is needed to examine its broader implications for mucosal inflammation under hypoxic conditions.
DNA, Mitochondrial/metabolism* ; Mouth Mucosa/pathology* ; Hypoxia/immunology* ; Methyltransferases/metabolism* ; Blood Platelets/metabolism* ; Animals ; Periodontitis/immunology* ; Humans ; Platelet Activation ; Mice

As the field of oral pathology has evolved, the nomenclature and classification of oral mucosal diseases with a remarkable risk of malignant transformation have undergone several modifications. In 2005, the World Health Organization (WHO) introduced the concept of oral potentially malignant disorders (OPMDs) as an alternative to the terms for oral precancerous lesions and precancerous conditions. In the consensus report by the WHO Collaborating Center for Oral Cancer of 2021, OPMD is defined as "any oral mucosal abnormality that is associated with a statistically increased risk of developing oral cancer."This definition encompasses a range of conditions, in-cluding oral leukoplakia, oral submucous fibrosis, proliferative verrucous leukoplakia, oral lichen planus, and other lesions. In light of the complex etiology, unclear pathogenesis, and carcinogenesis of OPMDs, early and precise diagnosis and treatment can contribute to the secondary prevention of oral cancer. For this reason, this review, which aims to provide a basis for the precise clinical diagnosis of OPMDs, was performed. Its aim was achieved by reviewing the historical evolution and research progress of the nomenclature, classification, and histopathological diagnostic criteria of OPMDs.
Humans ; Mouth Neoplasms/diagnosis* ; Precancerous Conditions/diagnosis* ; Leukoplakia, Oral/diagnosis* ; Lichen Planus, Oral/pathology* ; Oral Submucous Fibrosis/pathology* ; Mouth Mucosa/pathology* ; World Health Organization

OBJECTIVES: The aim of this study is to determine the effect of cannabinoid receptor (CB) 2 inhibitor on desmoglein 3 (DSG3) expression in HaCaT cells co-cultured with pemphigus serum. METHODS: Immunohistochemical staining was used to compare CB expression in pemphigus patients and normal individuals. Enzyme-linked immunosorbent assay (ELISA) was employed to quantify the concentration of CB2 in the serum of pemphigus patients and normal individuals. A correlation analysis was performed to examine the relationship between the serum CB2 and DSG of pemphigus patients. The CCK-8 assay was used to evaluate the inhibitory effect of AM630 on HaCaT cells, and the half-maximal inhibitory concentration (IC₅₀) value was utilized to determine the experimental concentration. Serum from normal individuals (negative control group) and pemphigus patients (pemphigus group) was co-cultured with HaCaT cells at a 1∶1 ratio. HaCaT cells cultured in complete medium were used as the control group. HaCaT cells in the pemphigus group treated with AM630 were employed as the AM630 group. Real-time polymerase chain reaction (PCR) and Western blot were conducted to assess the expression levels of CB2, DSG3, and β-catenin. Cell dissociation experiments were conducted to evaluate the effect of AM630 on the adhesion of HaCaT cells. RESULTS: Immunohistochemistry revealed significant differences in CB2 expression between pemphigus and normal mucosa (P<0.000 1), but no difference was found in CB1 expression. ELISA analysis revealed a statistically significant difference in the expression levels of CB2 in the serum between normal individuals and pemphigus patients (P<0.001). The expression of CB2 in the serum of pemphigus patients exhibited a significant positive correlation with that of DSG3 (r=0.831, P=0.003). The CCK-8 assay indicated that the IC₅₀ of AM630 on HaCaT cells was 0.55 μmol/L. Real-time PCR and Western blot showed that the expression levels of CB2 and DSG3 increased in the pemphigus group, while the expression level of β-catenin decreased compared with that in the AM630 groups (P<0.05). CONCLUSIONS CB2 is highly expressed in oral mucosal pemphigus. AM630 inhibits overexpression of CB2 and DSG3 and underexpression of β-catenin levels, which can provide new therapeutic targets for pemphigus.
Humans ; Pemphigus/pathology* ; Receptor, Cannabinoid, CB2/metabolism* ; Desmoglein 3/metabolism* ; Acantholysis/metabolism* ; Mouth Mucosa/pathology* ; HaCaT Cells ; Coculture Techniques ; beta Catenin/metabolism*

The integrity of the basal stem cell layer is critical for epithelial homoeostasis. In this paper, we review the expression of oral mucosal stem cell markers (OM-SCMs) in oral submucous fibrosis (OSF), oral potentially malignant disorders (OPMDs) and oral squamous cell carcinoma (OSCC) to understand the role of basal cells in potentiating cancer stem cell behaviour in OSF. While the loss of basal cell clonogenicity triggers epithelial atrophy in OSF, the transition of the epithelium from atrophic to hyperplastic and eventually neoplastic involves the reactivation of basal stemness. The vacillating expression patterns of OM-SCMs confirm the role of keratins 5, 14, 19, CD44, β1-integrin, p63, sex-determining region Y box (SOX2), octamer-binding transcription factor 4 (Oct-4), c-MYC, B-cell-specific Moloney murine leukaemia virus integration site 1 (Bmi-1) and aldehyde dehydrogenase 1 (ALDH1) in OSF, OPMDs and OSCC. The downregulation of OM-SCMs in the atrophic epithelium of OSF and their upregulation during malignant transformation are illustrated with relevant literature in this review.
Animals ; Carcinoma, Squamous Cell ; pathology ; Cell Transformation, Neoplastic ; pathology ; Mice ; Mouth Mucosa ; Mouth Neoplasms ; pathology ; Oral Submucous Fibrosis ; pathology ; Stem Cells

To analyze the incidence and distribution of oral mucosal diseases in Hunan Province and provide reference for prevention and treatment.
 Methods: The clinical data for all patients, who were treated in Xiangya Hospital of Central South University from April 2013 to March 2017, were collected. After screening, weighing and classifying, sex and age distribution for the disease was analyzed.
 Results: The female with the age between 40 to 49 were in the majority among 21 972 patients. The ratio between men to women was 1:1.05. According to the classification of diseases, the most common diseases were as follows: recurrent aphthous ulcer (27.17%), burning mouth syndrome (15.72%), oral submucous fibrosis (14.75%), oral lichen planus (10.38%), oral leukoplakia (4.21%), traumatic ulceration (4.14%), chronic cheilitis (3.47%), oral fungal infection (3.26%), and atrophic glossitis (2.74%). Recurrent oral ulcer (28.65%), burning mouth syndrome (23.70%) and oral lichen planus (13.31%) were the most common 3 kinds of oral mucosal diseases during females in Hunan. Oral submucous fibrosis was the most common oral mucosal disease among males in Hunan (28.56%).
 Conclusion: Recurrent oral ulcer, burning mouth syndrome and oral lichen planus are very popular in women in Hunan Province, and oral submucous fibrosis is the most common disease in male in this region. It shows a high trend of incidence in the surrounding provinces.
Adult ; Age Distribution ; Burning Mouth Syndrome ; epidemiology ; China ; epidemiology ; Female ; Fibrosis ; Humans ; Incidence ; Leukoplakia, Oral ; epidemiology ; Lichen Planus, Oral ; epidemiology ; Male ; Middle Aged ; Mouth Diseases ; epidemiology ; therapy ; Mouth Mucosa ; pathology ; Oral Submucous Fibrosis ; Oral Ulcer ; epidemiology ; Sex Distribution ; Stomatitis, Aphthous ; epidemiology

An 8-year-old girl who had experienced intermittent cough and fever over a 3 year period, was admitted after experiencing a recurrence for one month. One year ago the patient experienced a recurrent oral mucosal ulcer. Physical examination showed vitiligo in the skin of the upper right back. Routine blood tests and immune function tests performed in other hospitals had shown normal results. Multiple lung CT scans showed pulmonary infection. The patient had recurrent fever and cough and persistent presence of some lesions after anti-infective therapy. The antitubercular therapy was ineffective. Routine blood tests after admission showed agranulocytosis. Gene detection was performed and she was diagnosed with dyskeratosis congenita caused by homozygous mutation in RTEL1. Patients with dyskeratosis congenita with RTEL1 gene mutation tend to develop pulmonary complications. Since RTEL1 gene sequence is highly variable with many mutation sites and patterns and can be inherited via autosomal dominant or recessive inheritance, this disease often has various clinical manifestations, which may lead to missed diagnosis or misdiagnosis. For children with unexplained recurrent pulmonary infection, examinations of the oral cavity, skin, and nails and toes should be taken and routine blood tests should be performed to exclude dyskeratosis congenita. There are no specific therapies for dyskeratosis congenita at present, and when bone marrow failure and pulmonary failure occur, hematopoietic stem cell transplantation and lung transplantation are the only therapies. Androgen and its derivatives are effective in some patients. Drugs targeting the telomere may be promising for patients with dyskeratosis congenita.
Child ; Dyskeratosis Congenita ; complications ; therapy ; Female ; Humans ; Mouth Diseases ; etiology ; Mouth Mucosa ; pathology ; Recurrence ; Respiratory Tract Infections ; etiology ; Telomere ; drug effects ; Ulcer ; etiology

OBJECTIVETo evaluate the expression of voltage-gated potassium channel Kv3.4 and to determine its significance in oral squamous cell carcinoma (OSCC) and precancerous lesions.

METHODSImmunohistochemical SP methods were performed to detect the expression of Kv3.4 at tissue level on 57 paraffin-embedded samples collected from Pathology Department of Anhui Province Stomatological Hospital during January 2013 to June 2014. The relationships between the expression of Kv3.4 and precancerous lesion and clinical pathologic factors of oral squamous cell carcinoma, such as pathologic classification, clinical stage and lymph node metastasis, were also analyzed. Totally 6 samples of normal oral mucosa tissue, 23 samples of OSCC and 13 samples of precancerous lesions were collected from the Department of Oral and Maxillofacial Surgery of The First Affiliated Hospital of Anhui Medical University during May 2014 to March 2015. Real-time quantitative PCR and Western blotting were used to detect the expression of Kv3.4 in these 42 samples at molecular and protein levels.

RESULTSReal-time quantitative PCR showed the relative expression quantity of Kv3.4 in normal oral mucosa, precancerous lesions, and OSCC tissues were 0.85±0.48, 3.50±2.51 and 18.48±7.70, respectively. The relative expression quantity of Kv3.4 in OSCC and precancerous lesions were higher than that in normal group, the differences were both statistically significant (P=0.002, P=0.029). The relative expression quantities of Kv3.4 protein in precancerous and OSCC tissues were 0.87±0.14 and 0.35±0.03 respectively by Western blotting, and both were higher than that in normal tissues (0.18±0.10). The differences were statistically significant (P=0.002). In 57 paraffin-embedded samples, the positive expression rates of Kv3.4 in normal, precancerous and OSCC tissues were 2/6, 13/18 and 95% (37/39), respectively. The differences were statistically significant(P<0.05). However, the expression of Kv3.4 did not show obvious correlation with patients' genders, presence of lymph node metastasis and clinical stages (P>0.05).

CONCLUSIONSThe expression of Kv3.4 is positively correlated to OSCC's occurrence and development. Detection of the expression of Kv3.4 may be used for early diagnosis and prognostic judgment of oral squamous cell carcinoma and precancerous lesions.

Carcinoma, Squamous Cell ; metabolism ; pathology ; Female ; Humans ; Lymphatic Metastasis ; Male ; Mouth Mucosa ; metabolism ; Mouth Neoplasms ; metabolism ; pathology ; Potassium Channels, Voltage-Gated ; metabolism ; Precancerous Conditions ; metabolism ; pathology ; Prognosis ; Sex Factors

Diagnosis, Differential ; Humans ; Mouth Mucosa ; pathology ; Syndrome

The identification and characterization of stem cells is a major focus of developmental biology and regenerative medicine. The advent of genetic inducible fate mapping techniques has made it possible to precisely label specific cell populations and to follow their progeny over time. When combined with advanced mathematical and statistical methods, stem cell division dynamics can be studied in new and exciting ways. Despite advances in a number of tissues, relatively little attention has been paid to stem cells in the oral epithelium. This review will focus on current knowledge about adult oral epithelial stem cells, paradigms in other epithelial stem cell systems that could facilitate new discoveries in this area and the potential roles of epithelial stem cells in oral disease.
Adult Stem Cells ; cytology ; physiology ; Animals ; Asymmetric Cell Division ; Biomarkers ; Cell Proliferation ; Clone Cells ; Epithelial Cells ; cytology ; Genetic Drift ; Humans ; Mouth Mucosa ; cytology ; Mouth Neoplasms ; pathology ; Neoplastic Stem Cells