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

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*

Tight junctions (TJs) are the most apical intercellular junctions of epithelial cells formed by occludin, claudins, junctional adhesion molecules (JAMs), and zonula occludens (ZO). Tight junction proteins can sense the presence of bacteria and regulate the transcription of target genes that encode effectors and regulators of the immune response. The aim of this study was to determine the impact of TJ proteins in response to Porphyromonas gingivalis (P. gingivalis), P. gingivalis lipopolysaccharide (P. gingivalis LPS), and extracellular adenosine triphosphate (ATP) in the oral epithelial cell culture model. Quantified real time-polymerase chain reaction (RT-PCR), immunoblots, and immunostaining were performed to assess the gene and protein expression in TJs. It was found that P. gingivalis infection led to transient upregulation of the genes encoding occludin, claudin-1, and claudin-4 but not JAM-A, claudin-15, or ZO-1, while P. gingivalis LPS increased claudin-1, claudin-15, and ZO-1 and decreased occludin, JAM-A, and claudin-4. Tight junction proteins showed significant upregulation in the above two groups when cells were pretreated with ATP for 3 h. The findings indicated that P. gingivalis induced the host defence responses at an early stage. P. gingivalis LPS exerted a more powerful stimulatory effect on the disruption of the epithelial barrier than P. gingivalis. ATP stimulation enhanced the reaction of TJ proteins to P. gingivalis invasion and LPS destruction of the epithelium.International Journal of Oral Science (2018) 10, e8; doi:10.1038/ijos.2017.51; published online 10 January 2018.
Adenosine Triphosphate ; pharmacology ; Cells, Cultured ; Epithelial Cells ; cytology ; Gene Expression ; Humans ; Immunoblotting ; Lipopolysaccharides ; pharmacology ; Mouth Mucosa ; cytology ; Porphyromonas gingivalis ; immunology ; Real-Time Polymerase Chain Reaction ; Tight Junction Proteins ; metabolism ; Up-Regulation

OBJECTIVE: This study aimed to investigate the expression and relationship of microtubule-associated protein 1 light chain 3 (LC3) and mammalian target of rapamycin (mTOR) in normal oral mucosa, oral leukoplakia (OLK), and oral squamous cell carcinoma (OSCC). This work also analyzed the relationship between expression levels and clinical factors. This study evaluated the clinical value of LC3B and mTOR as indices to determine the carcinogenic potential of OLK. METHODS: Immunohistochemistry was used to detect the expression of LC3B and mTOR in 20 cases of normal oral mucosa, 120 cases of OLK, and 30 cases of OSCC. The clinical data of 120 patients with OLK were analyzed. The relationships between expression levels and clinical factors were investigated. RESULTS: In normal oral mucosa, OLK and OSCC, the positive rates of LC3B expression were 85.0%, 65.8% and 33.3% (P<0.05), whereas the positive rates of mTOR expression were 20.0%, 48.3% and 76.7% (P<0.05). The expression levels of LC3B and mTOR were correlated and related to clinical typing of OLK (P<0.05). CONCLUSIONS LC3B and mTOR can be used as molecular biomarkers for early detection of OLK.
Biomarkers, Tumor ; metabolism ; Carcinoma, Squamous Cell ; diagnosis ; metabolism ; Humans ; Leukoplakia, Oral ; diagnosis ; metabolism ; Microtubule-Associated Proteins ; metabolism ; Mouth Mucosa ; Mouth Neoplasms ; diagnosis ; metabolism ; TOR Serine-Threonine Kinases ; metabolism

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

OBJECTIVEThis study investigates the circadian variation rules of the clock gene Per2 and clock-controlled genes of vascular endothelial growth factor (VEGF), Ki67, c-Myc, and P53 in different stages of carcinogenesis in buccal mucosa carcinoma and their roles in the development of buccal mucosa carcinoma.

METHODSNinety Syrian golden hamsters were housed under. 12 h light/12 h dark cycles. Dimethylbenzanthracene (DMBA) was used to establish the carcinoma model by smearing the golden hamster buccal mucosa. Before DMBA painting and after 6 and 14 weeks, the hamsters were sacrificed at six time points within a period of 24 h (i.e., 4, 8, 12, 16, 20, and 24 h after light onset), and the normal buccal mucosa, precancerous lesions, and cancer tissues were simultaneously obtained. Hematoxylin and eosin stained sections were prepared to observe the canceration of each tissue. Real time polymerase chain reaction was used to detect the mRNA expression of Per2, VEGF, Ki67, c-Myc, and P53. Cosine analysis was employed to determine the circadian-rhythm variations of Per2, VEGF, Ki67, c-Myc, and P53 mRNA expression in terms of median, amplitude, and acrophase.

RESULTSThe expression of Per2, VEGF, P53, and c-Myc mRNA in three different stages appeared with circadian rhythms (P<0.05), whereas the Ki67 mRNA was expressed with circadian rhythm only in normal and precancerous lesion stages (P<0.05). The midline-estimating statistic of rhythms (MESORs) of Per2 and P53 mRNA were significantly down-regulated with the development of cancer (P<0.05), whereas the MESORs of VEGF, c-Myc, and Ki67 mRNA were up-regulated (P<0.05). The amplitude of P53 mRNA significantly decreased with the development of cancer (P<0.05). Moreover, compared with the normal group, the amplitudes of Per2, VEGF, Ki67, and c-Myc mRNA significantly increased in precancerous lesions and cancer tissue (P<0.05). In precancerous stage, the acrophases of Per2, VEGF, and c-Myc mRNA were earlier than that in the normal group, whereas that of Ki67 and P53 mRNA were delayed.

CONCLUSIONThe circadian-rhythm characteristics of the clock gene Per2 and clock-controlled gene expression of VEGF, Ki67, c-Myc, and P53 mRNA have changed with the occurrence and development of carcinoma.

9,10-Dimethyl-1,2-benzanthracene ; Animals ; Carcinogenesis ; Carcinoma, Squamous Cell ; metabolism ; Circadian Rhythm ; Cricetinae ; Mesocricetus ; Mouth Mucosa ; metabolism ; Mouth Neoplasms ; metabolism ; Neoplasm Staging ; Period Circadian Proteins ; genetics ; metabolism ; RNA, Messenger ; Real-Time Polymerase Chain Reaction ; Vascular Endothelial Growth Factor A

OBJECTIVE: To explore and analyze the the expression change of miRNA associated with oral submucous fibrosis (OSF) treated by the Salvia combined with law-dose prednisolone. METHODS: Ten pairs of tissues from patients with typical early or advanced stage clinical pathological features of OSF and their paired normal tissues (internal control), were selected respectively. The miRNA expression profiles between the OSF and its paired controls were compared by the Affymetrix analysis. The primary normal oral mucous cells were cultured in arecoline (50 μg/mL) for 3, 6, 12 d (0 d ser ved as cont rol), and the primary OSF-fibroblast cells were cultured with Salvia (90 mg/mL) combined with low-dose prednisolone for 12, 24, 36 h (0 h served as control). The differential expression of miRNA was detected. RESULTS: Arecoline induced the expression changes of miRNAs in normal mucosal cells. Salvia combined with low doses of prednisolone reversed the related miRNA expression. CONCLUSION MiRNAs play an essential role in the occurrence and development of OSF. Salvia combined with low-dose prednisolone can reverse the expression of related miRNAs in OSF cells.
Arecoline ; Cells, Cultured ; Coculture Techniques ; Fibroblasts ; cytology ; drug effects ; Humans ; MicroRNAs ; metabolism ; Mouth Mucosa ; cytology ; drug effects ; Oral Submucous Fibrosis ; metabolism ; Prednisolone ; pharmacology ; Salvia ; chemistry ; Transcriptome

In the present study, we investigate the expression profile of the epidermal growth factor receptor family, which comprises EGFR/ErbB1, HER2/ErbB2, HER3/ErbB3 and HER4/ErbB4 in oral leukoplakia (LP). The expression of four epidermal growth factor receptor (EGFR) family genes and their ligands were measured in LP tissues from 14 patients and compared with levels in 10 patients with oral lichen planus (OLP) and normal oral mucosa (NOM) from 14 healthy donors by real-time polymerase chain reaction (PCR) and immunohistochemistry. Synchronous mRNA coexpression of ErbB1, ErbB2, ErbB3 and ErbB4 was detected in LP lesions. Out of the receptors, only ErbB4 mRNA and protein was more highly expressed in LP compared with NOM tissues. These were strongly expressed by epithelial keratinocytes in LP lesions, as shown by immunohistochemistry. Regarding the ligands, the mRNA of Neuregulin2 and 4 were more highly expressed in OLP compared with NOM tissues. Therefore, enhanced ErbB4 on the keratinocytes and synchronous modulation of EGFR family genes may contribute to the pathogenesis and carcinogenesis of LP.
Adult ; Aged ; Amphiregulin ; Betacellulin ; EGF Family of Proteins ; Epidermal Growth Factor ; metabolism ; Epiregulin ; Female ; Gene Expression Profiling ; Glycoproteins ; metabolism ; Heparin ; metabolism ; Heparin-binding EGF-like Growth Factor ; Humans ; Intercellular Signaling Peptides and Proteins ; metabolism ; Keratinocytes ; metabolism ; Leukoplakia, Oral ; metabolism ; Lichen Planus, Oral ; metabolism ; Ligands ; Male ; Middle Aged ; Mouth Mucosa ; metabolism ; Nerve Growth Factors ; Neuregulins ; metabolism ; RNA, Messenger ; metabolism ; Real-Time Polymerase Chain Reaction ; Receptor, Epidermal Growth Factor ; metabolism ; Receptor, ErbB-2 ; metabolism ; Receptor, ErbB-3 ; metabolism ; Receptor, ErbB-4 ; Receptors, Cell Surface ; metabolism ; Transforming Growth Factor alpha ; metabolism ; Up-Regulation ; physiology

OBJECTIVETo study the effects of dihydromyricetin (DMY) on tumor necrosis factor (TNF-alpha) and NF-kappaB p65 cells of the recurrent aphthous ulcer (RAU) rat.

METHODSixty of Sprague Dawley (SD) rats are randomly divided into 6 groups. The rat RAU models was established by injection of immunogen composed of the homogenate supernate of homogeneous oral mucosa from SD rats and Freund's complete adjuvant (FCA) into rat backs subcutaneously once every two weeks for 5 times, and the only FCA injected as normal control. DMY(50,100, 200 mg x kg(-1)) and licorzine (67.5 mg x kg(-1)) were given intragastrically once daily for 7 days on the day of the last immunogen injection, respectively. Water was given instead of drugs in normal and model control groups. The blood was got from the fundus oculi vein of rats on the day after last administration, the serum was separated. Then the rats were put to death with the cervical dislocation and decollated on the ice stage. Two sides of rat buccal mucosal tissue were cut. One side of them was put into 4% neutral formalin and another was added into 10 times of phosphate buffer to homogenize it homogenate. The oral mucosa ulcer occurrence of rats was observed by the histopathology. The content of TNF-alpha in serum and oral mucosa was assayed with ELISA; the expression of NF-kappaB cells was determined by the immunohistochemisty and macrophagus was determined by azure-feosin-dyeing in oral mucosa tissue. The expression of TNF-alpha mRNA in serum and oral mucosa was detected by reverse transcription polymerase chain reaction.

RESULTIn RAU rats, oral mucosa ulcer occurred, the content of TNF-alpha raised and the expression of TNF-alpha mRNA increased in serum and oral mucosa, the expression of positive NF-kappaB p65 cells and the amount of macrophages went up in oral mucosa. DMY and licorzine significantly reduced occurrence of oral mucosa ulcer in RAU rats, lowered content of TNF-alpha and the expression of TNF-alpha mRNA in serum and oral mucosa, reduced expression of positive NF-kappaB p65 cells and the amount of macrophages.

CONCLUSIONIt is considered that DMY could inhibited occurrence of oral mucosa ulcer in RAU rats. One principle of it's effects could be that DMY controlled NF-kappaB p65 regulation on transcription and release of TNF-alpha mRNA in macrophages in oral mucosa ulcer tissue and lead to fall of TNF-alpha content in oral mucosa tissue causing role of anti-oral mucosa ulcer.

Animals ; Disease Models, Animal ; Female ; Flavonols ; administration & dosage ; Humans ; Macrophages ; drug effects ; immunology ; Male ; Mouth Mucosa ; drug effects ; metabolism ; Rats ; Rats, Sprague-Dawley ; Stomatitis, Aphthous ; drug therapy ; genetics ; immunology ; Transcription Factor RelA ; genetics ; immunology ; Tumor Necrosis Factor-alpha ; genetics ; immunology