Caspase-12 silencing attenuates inhibitory effects of cigarette smoke extract on NOD1 signaling and hBDs expression in human oral mucosal epithelial cells

Cigarette smoke exposure is associated with increased risk of various diseases. Epithelial cells-mediated innate immune responses to infectious pathogens are compromised by cigarette smoke. Although many studies have established that cigarette smoke exposure affects the expression of Toll-liked receptor (TLR), it remains unknown whether the nucleotide-binding oligomerization domain-containing protein 1 (NOD1) expression is affected by cigarette smoke exposure. In the study, we investigated effects of cigarette smoke extract (CSE) on NOD1 signaling in an immortalized human oral mucosal epithelial (Leuk-1) cell line. We first found that CSE inhibited NOD1 expression in a dose-dependent manner. Moreover, CSE modulated the expression of other crucial molecules in NOD1 signaling and human β defensin (hBD) 1, 2 and 3. We found that RNA interference-induced Caspase-12 silencing increased NOD1 and phospho-NF-κB (p-NF-κB) expression and down-regulated RIP2 expression. The inhibitory effects of CSE on NOD1 signaling can be attenuated partially through Caspase-12 silencing. Intriguingly, Caspase-12 silencing abrogated inhibitory effects of CSE on hBD1, 3 expression and augmented induced effect of CSE on hBD2 expression. Caspase-12 could play a vital role in the inhibitory effects of cigarette smoke on NOD1 signaling and hBDs expression in oral mucosal epithelial cells.

Attenuation of NLRP3 Inflammasome by Cigarette Smoke is Correlated with Decreased Defense Response of Oral Epithelial Cells to Candida albicans

BACKGROUND

It is well recognized that both smoke and Candida infection are crucial risk factors for oral mucosal diseases. The nucleotide-binding domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome and its downstream effectors, interleukin (IL)-1β and IL-18, are pivotal to the host defense against Candida and other pathogens.

METHODS

The present study was designed to explore the effects of cigarette smoke and C. albicans on the NLRP3 inflammasome and its downstream signal pathway via in vitro cell model. Oral epithelial cells (Leuk-1 cells) were exposed to cigarette smoke extract (CSE) for 3 days and/or challenged with C. albicans.

RESULTS

Microscopically, Leuk-1 cells exerted a defense response to C. albicans by markedly limiting the formation of germ tubes and microcolonies. CSE clearly eliminated the defense response of Leuk-1 cells. Functionally, CSE repressed NLRP3 inflammasome, and IL-1β and IL-18 activation induced by C. albicans in Leuk-1 cells.

CONCLUSION

Our results suggested that in oral epithelial cells, the NLRP3 inflammasome might be one of the target pathways by which CSE attenuates innate immunity and leads to oral disorders.

SS-31 mitigates oxidative stress and restores mitochondrial function in cigarette smoke-damaged oral epithelial cells via PINK1-mediated mitophagy

Smoking is a well-established risk factor for several oral diseases, including oral cancer, oral leukoplakia and periodontitis, primarily related to reactive oxygen species (ROS). SS-31, a mitochondria-targeting tetrapeptide, has exhibited demonstrable efficacy in medical conditions by attenuating mitochondrial ROS production. However, its potential in the treatment of oral diseases remains underexplored. The aim of this study was to investigate the therapeutic potential of SS-31 in mitigating smoking-induced oral epithelial injury. Through in vitro experiments, our results indicate that SS-31 plays a protective role against cigarette smoke extract (CSE) by reducing oxidative stress, attenuating inflammatory response, and restoring mitochondrial function. Furthermore, we found that mitophagy, regulated by PINK1 (PTEN-induced putative kinase 1)/Parkin (Parkin RBR E3 ubiquitin-protein ligase), was critical for the protective role of SS-31. Our findings offer valuable insights into SS-31's therapeutic potential in mitigating CSE-induced oxidative stress, inflammatory response, and mitochondrial dysfunction in oral epithelial cells. This study provides novel intervention targets for smoking-related oral diseases.

Antimicrobial Effect of Extracellular Vesicles Derived From Human Oral Mucosal Epithelial Cells on Candida albicans

Candida albicans (C. albicans) is a commensal microorganism that colonizes the mucosal surfaces of healthy individuals. Changes in the host or environment can lead to overgrowth of C. albicans and infection of the host. Extracellular vesicles (EVs) are released by almost all cell types and play an increasingly recognized role in fighting microbial infection. The aim of the present study was to assess whether EVs derived from human oral mucosal epithelial (Leuk-1) cells can suppress the growth and invasion of C. albicans. The in vitro efficacy of Leuk-1-EVs against C. albicans was assessed by optical microscopy, laser scanning confocal microscopy, scanning electron microscopy, and transmission electron microscopy. The germ tube formation rate, the percentage of hyphae and the microcolony optical density were also used to analyze the growth of C. albicans in a coculture model with Leuk-1 cells and EVs or after inhibition of the secretion of EVs. A mouse model of oral candidiasis was established and submucosal injection of Leuk-1-EVs in the tongue was performed. Macroscopic observation, H&E staining, PAS staining, and scanning electron microscopy were used to assess antifungal effects of Leuk-1-EVs in vivo. The in vitro results showed that the growth of C. albicans was inhibited and that the morphology and ultrastructure were changed following Leuk-1-EVs treatment. The in vivo results exhibited that white lesions of the tongue, C. albicans infection, and oral mucosal inflammation of the infected mice were significantly alleviated after Leuk-1-EVs treatment. We thus reveal an antifungal capability of EVs derived from oral epithelial cells against C. albicans that is mediated by direct damage effects and potential synergy between EVs and human oral mucosal epithelial cells. This finding offers an intriguing, previously overlooked method of antifungal defense against C. albicans.

Heat-killed Prevotella intermedia promotes the progression of oral squamous cell carcinoma by inhibiting the expression of tumor suppressors and affecting the tumor microenvironment

BACKGROUND

Oral microbial dysbiosis contributes to the development of oral squamous cell carcinoma (OSCC). Our previous study showed that Prevotella intermedia (P. intermedia) were enriched in the oral mucosal surface, plaque, and saliva of patients with OSCC. Intratumoral microbiome could reshape the immune system and influence the development of various tumors. However, the invasion status of human OSCC tissues by P. intermedia and the pathway through which intratumoral P. intermedia potentiates tumor progression remain unexplored.

METHODS

P. intermedia in human OSCC or normal tissues was detected by FISH. A mouse OSCC cell line SCC7 was adopted to investigate the effects of heat-killed P. intermedia treatment on cell proliferation, invasion, and cytokine release by using CCK-8 assay, transwell invasion assay and ELISA. Moreover, we established a mouse transplanted tumor model by using SCC7 cells, injected heat-killed P. intermedia into tumor tissues, and investigated the effects of heat-killed P. intermedia on tumor growth, invasion, cytokine levels, immune cell infiltrations, and expression levels by using gross observation, H&E staining, ELISA, immunohistochemistry, mRNA sequencing, and transcriptomic analysis.

RESULTS

Our results indicated that P. intermedia were abundant in OSCC and surrounding muscle tissues. Heat-killed P. intermedia promoted SCC7 cell proliferation, invasion and proinflammatory cytokine secretions, accelerated transplanted tumor growth in mice, exacerbate muscle and perineural invasion of OSCC, elevated the serum levels of IL-17A, IL-6, TNF-α, IFN-γ, and PD-L1, induced Treg cells M2 type macrophages in mouse transplanted tumors. The data of transcriptomic analysis revealed that heat-killed P. intermedia increased the expression levels of inflammatory cytokines and chemokines while reduced the expression levels of some tumor suppressor genes in mouse transplanted tumors. Additionally, IL-17 signaling pathway was upregulated whereas GABAergic system was downregulated by heat-killed P. intermedia treatment.

CONCLUSIONS

Taken together, our results suggest that P. intermedia could inhibit the expression of tumor suppressors, alter the tumor microenvironment, and promote the progression of OSCC.

The potential roles of cigarette smoke-induced extracellular vesicles in oral leukoplakia

BACKGROUND

The onset of oral leukoplakia (OLK), the most common oral lesion with a high risk of malignant transformation, is closely associated with the exposure of cigarette smoke. Cigarette smoke is a complicated mixture of more than 4500 different chemicals including various oxidants and free radical, which contributes to the onset of immune and inflammatory response or even carcinogenesis. Recent studies have proved that the exposure of cigarette smoke leads to the onset and aggravation of many diseases via significantly changed the production and components of extracellular vesicles. The extracellular vesicles are membrane-enclosed nanosized particles secreted by diverse cells and involved in cell-cell communication because of their ability to deliver a number of bioactive molecules including proteins, lipids, DNAs and RNAs. Getting insight into the mechanisms of extracellular vesicles in regulating OLK upon cigarette smoke stimulation contributes to unravel the pathophysiology of OLK in-depth. However, evidence done on the role of extracellular vesicles in cigarette smoke-induced OLK is still in its infancy.

MATERIALS AND METHODS

Relevant literatures on cigarette smoke, oral leukoplakia and extracellular vesicles were searched in PubMed database.

CONCLUSIONS

In this review, we summarize the recent findings about the function of extracellular vesicles in the pathogenesis of cigarette smoke-induced diseases, and to infer their potential utilizations as diagnostic biomarkers, prognostic evaluation, and therapeutic targets of OLK in the future.

Clinical Features and Histopathological Analysis of Oral Lichen Planus: An Analysis of 105 Chinese Patients

PURPOSE

To study the clinical and pathological characteristics of oral lichen planus (OLP) in a large sample.

MATERIALS AND METHODS

A comprehensive analysis was conducted on 105 patients with oral lichen planus (OLP), considering various factors including sex, age, disease site, lesion type, lesion area, morphological characteristics, self-reported symptoms, and history of systemic diseases. Histopathological examination was performed for each patient, and the pathology results were analysed according to sex and age group.

RESULTS

70.5% of the OLP patients were female, and OLP was most likely to occur in the cheek, followed by the tongue, lips, gums and palate. The patients with moderate pain according to the VAS score accounted for 60%. Thirty-nine percent of the OLP patients had a systemic disease, and the most common clinical type of OLP was nonerosive. Most of the pathological results showed liquefaction degeneration of basal cells and infiltration of lamina propria lymphocytes. There was no statistically significant difference in pathological manifestations between male and female patients, and there were statistically significant differences in pathological manifestations among different ages patients.

CONCLUSION

This study analysed the sociodemographic data and clinical manifestations of 105 OLP patients to guide follow-up treatment planning and disease monitoring. Moreover, pathological manifestations should be analysed to avoid delayed treatment and to monitor for carcinogenesis. Furthermore, the correlation of pathological manifestations among OLP patients with different sexes and ages is conducive to further research on the specific differential manifestations and possible underlying mechanisms involved.

A metagenome-wide association study of the gut microbiota in recurrent aphthous ulcer and regulation by thalidomide

Recurrent aphthous ulcer (RAU), one of the most common diseases in humans, has an unknown etiology and is difficult to treat. Thalidomide is an important immunomodulatory and antitumor drug and its effects on the gut microbiota still remain unclear. We conducted a metagenomic sequencing study of fecal samples from a cohort of individuals with RAU, performed biochemical assays of cytokines, immunoglobulins and antimicrobial peptides in serum and saliva, and investigated the regulation effects of thalidomide administration and withdrawal. Meanwhile we constructed the corresponding prediction models. Our metagenome-wide association results indicated that gut dysbacteriosis, microbial dysfunction and immune imbalance occurred in RAU patients. Thalidomide regulated gut dysbacteriosis in a species-specific manner and had different sustainable effects on various probiotics and pathogens. A previously unknown association between gut microbiota alterations and RAU was found, and the specific roles of thalidomide in modulating the gut microbiota and immunity were determined, suggesting that RAU may be affected by targeting gut dysbacteriosis and modifying immune imbalance. In-depth insights into sophisticated networks consisting of the gut microbiota and host cells may lead to the development of emerging treatments, including prebiotics, probiotics, synbiotics, and postbiotics.

Cigarette smoking induces the activation of RIP2/caspase-12/NF-κB axis in oral squamous cell carcinoma

Cigarette smoking is one of the major risk factors for the occurrence and progression of oral squamous cell carcinoma (OSCC). Receptor-interacting protein 2 (RIP2) has been involved in mucosal immunity and homeostasis via a positive regulation of nuclear factor κB (NF-κB) transcription factor activity. Caspase-12 can bind to RIP2 and dampen mucosal immunity. However, the roles of RIP2/NF-κB and caspase-12 in OSCC induced by cigarette smoking remain unknown. Herein, we investigated the effects of cigarette smoking on the RIP2/NF-κB and caspase-12 in human OSCC tissues and OSCC cell lines (HSC-3). We first observed that RIP2 mediated NF-κB activation and caspase-12 upregulation in OSCC patients with cigarette smoking and cigarette smoke extract (CSE)-treated HSC-3 cells, respectively. Moreover, we confirmed that the downregulation of RIP2 by siRNA resulted in the reduction of caspase-12 expression and NF-κB activity in the presence of CSE treatment in vitro. In summary, our results indicated that cigarette smoking induced the activation of the RIP2/caspase-12/NF-κB axis and it played an important role in the development of OSCC. The RIP2/caspase-12/NF-κB axis could be a target for OSCC prevention and treatment in the future.

[Research progress and frontier analysis of Laugier-Hunziker syndrome at home and abroad based on Citespace]

Objective: Analyzing the overview, changing trends, hotspots, and frontiers of the rare oral disease Laugier-Hunziker syndrome (LHS) using bibliometrics. Methods: Search the CNKI (China National Knowledge Infrastructure) and Web of science core collection (WOSCC) databases. The time span for Chinese literature is from January 1992 to December 2023, and for English literature is from January 1986 to December 2023. Utilize Citespace software to conduct visualized analysis on various aspects of the literature, including publication volume, authors, countries, institutions, journals, and keywords. Results: This study included a total of 112 articles (25 in Chinese and 87 in English). The overall publication volume showed a fluctuating slow-growth trend. Foreign authors Lenane P and Powell F had the highest number of publications. The team from Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, had the most publications among domestic authors. In terms of international collaboration, the United States demonstrated the highest centrality, but the collaborative network worldwide appeared relatively loose. University College Dublin was the foreign institution with the highest publication volume, while Peking Union Medical College Hospital was the domestic institution with the most publications. The journal with the highest number of foreign publications was the Journal of The American Academy of Dermatology, and the journal with the most domestic publications was the Chinese Leprosy Skin Disease Journal. Research hotspots for Laugier-Hunziker syndrome included lesion sites and differential diagnosis, while the frontiers of research encompassed differential diagnosis, disease management, and clinical manifestations related to oral mucosa. Conclusions: Laugier-Hunziker syndrome research shows a focus on differential diagnosis and symptom management. Future studies should prioritize optimizing treatment methods and emphasizing psychological support, while promoting interdisciplinary collaboration and the integration of global research networks to improve clinical diagnostic and therapeutic outcomes.

NOD1, RIP2 and Caspase12 are potentially novel biomarkers for oral squamous cell carcinoma development and progression

Although increasing studies have indicated that Nucleotide-oligomerization domain-containing protein 1 (NOD1) signaling could play an important role in gastrointestinal tumorigenesis, the protein expression and function of NOD1 signaling have not been understood well in oral squamous cell carcinoma (OSCC) progression. The objective of this study is, thus, to examine protein expression of NOD1 signaling immunohistochemically in normal, premalignant and malignant specimens of oral cavity, and to take insights into the association between the protein expression of NOD1 signaling pathway and OSCC precession. In this study immunohistochemical expression of NOD1, Receptor-interacting protein 2 (RIP2), Caspase12, human β Defensin1, 2 and 3 (hBD1, 2, 3) was examined in 15 normal controls, 30 cases of oral leukoplakia (OLK) and 60 cases of OSCC. The immunostaining score was assessed by 2 pathologists, respectively. We found that the expression of NOD1, RIP2, Caspase12, hBD1, 2, and 3 decreased along with the progression of OSCC. NOD1 expression was correlated significantly to tumor differentiation, lymph node metastasis, and tumor size. Our results also showed the correlation of hBD2, 3 to lymph node metastasis of OSCC. These results suggest that the dysfunction of NOD1 signaling pathways could be associated with OSCC development and progression. NOD1, RIP2 and Caspase12 could be used as potentially novel biomarkers for oral carcinogenesis.

[Expression of nucleotide-binding oligomerization domain 1, nuclear factor-kappa B and human beta-defensins in candidal albicans leukoplakia]

OBJECTIVE

To examine the expression of nucleotide-binding oligomerization domain 1 (NOD1), nuclear factor-kappa B (NF-κB) and human beta-defensins in candidal albicans leukoplakia and to investigate the effect of candida albicans infection on key proteins in NOD1 signaling pathway and the expression of human beta-defensin.

METHODS

Forty cases of oral leukoplakia samples were collected and stained by hematoxylin-eosin staining, periodic acid-Schiff staining, silver staining and immunohistochemical methods. Nineteen samples were positive with these four methods and judged as candidal albicans leukoplakia, and the other twenty- one samples judged as leukoplakia without candidal albicans infection. Western blotting was used to detect the expressions of NOD1 and NF-κB in these forty samples. In addition, the immunohistochemical method was adopted to investigate the relationship between NOD1, NF-κB, human beta-defensin 1, 2, 3 expressions and candida albicans.

RESULTS

The positive rate of candida albicans in oral leukoplakia was 48% (19/40). The expressions of NOD1 and NF-κB in the candida albicans leukoplakia were lower than that in leukoplakia without candida albicans infection. The mean optical density value of NOD1, NF-κB, human beta-defensin 1, 2, 3 in candidal albicans leukoplakia were 0.25 ± 0.01, 0.30 ± 0.02, 0.35 ± 0.02, 0.42 ± 0.03, 0.36 ± 0.02 respectively, which were significantly lower than that in leukoplakia without candida albicans infection (0.31 ± 0.02, 0.47 ± 0.03, 0.42 ± 0.02, 0.53 ± 0.04, 0.47 ± 0.03) (P < 0.05).

CONCLUSIONS

By inhibiting the NOD1 signaling pathway, candida albicans infection may reduce the expression level of human beta-defensin 1, 2, 3 in oral leukoplakia.

Probiotics and prebiotics: new treatment strategies for oral potentially malignant disorders and gastrointestinal precancerous lesions

Oral potentially malignant disorders (OPMDs) and gastrointestinal precancerous lesions (GPLs) are major public health concerns because of their potential to progress to cancer. Probiotics, prebiotics, and engineered probiotics can positively influence the prevention and management of OPMDs and GPLs. This review aims to comprehensively review the application status of probiotics, prebiotics and engineered probiotics in OPMDs and GPLs, explore their potential mechanisms of action, and anticipate their future clinical use.

Effect of different restorative design and materials on stress distribution in cracked teeth: a finite element analysis study

OBJECTIVES

To compare the stress distribution and crack propagation in cracked mandibular first molar restored with onlay, overlay, and two types of occlusal veneers using two different CAD/CAM materials by Finite Element Analysis (FEA).

MATERIALS AND METHODS

A mandibular first molar was digitized using a micro CT scanning system in 2023. Three-dimensional dynamic scan data were transformed, and a 3D model of a cracked tooth was generated. Finite element models of four different models (onlay, overlay, and two types of occlusal veneer restored teeth) were designed. Two different CAD/CAM materials, including Lava Ultimate (LU) and IPS e.max CAD (EMX), were specified for both models. Each model was subjected to three different force loads on the occlusal surfaces. Stress distribution patterns and the maximum von Mises (VM) stresses were calculated and compared.

RESULTS

Compared to the base model, all restorations showed that high-stress concentration moved from the lower margin of the crack area towards the top of the crack area. The EMX-restored onlay, overlay, and occlusal veneer 2 had the lower stress in the cracked area and the lower average von Mises stress levels at the lower margin along the cracked line, especially under the 225N lateral force (P < 0.05). The occlusal veneer 1 filled with resin had a poorer stress distribution and higher stress concentration of stress at the remaining crack than the occlusal veneer 2 without resin filled inside.

CONCLUSIONS

The EMX restorations with onlay, overlay, and occlusal veneer 2 showed lower stress concentration at the lower margin of crack surface compared to the LU-restored models. The occlusal veneer with internal resin filler exhibited higher stress on the end of the lower margin of the crack surface.

CLINICAL RELEVANCE

Our results suggest that onlay, overlay ceramic restorations and occlusal veneer (without resin filling inside) may be a favorable method to prevent further crack propagation.

TRIAL REGISTRATION

A protocol was specified and registered with the Chinese Clinical Trial Registry (ChiCTR) on 2022-04-12 (registration number: ChiCTR2200058630).

Prevotella intermedia boosts OSCC progression through ISG15 upregulation: a new target for intervention

PURPOSE

Periodontitis-associated bacteria, such as Porphyromonas gingivalis and Fusobacterium nucleatum, are closely linked to the risk of oral squamous cell carcinoma (OSCC). Emerging studies have indicated that another common periodontal pathogen, Prevotella intermedia (P. intermedia), is enriched in OSCC and could affect the occurrence and progression of OSCC. Our aim is to determine the effects of P. intermedia on the progression of OSCC and the role of antibiotics in reversing these effects.

METHODS

In this study, a murine xenograft model of OSCC was established, and the mice were injected intratumorally with PBS (control group), P. intermedia (P.i group), or P. intermedia combined with an antibiotic cocktail administration (P.i + ABX group), respectively. The effects of P. intermedia and ABX administration on xenograft tumor growth, invasion, angiogenesis, and metastasis were investigated by tumor volume measurement and histopathological examination. Enzyme-linked immunosorbent assay (ELISA) was used to investigate the changes in serum cytokine levels. Immunohistochemistry (IHC) was adopted to analyze the alterations in the levels of inflammatory cytokines and infiltrated immune cells in OSCC tissues of xenograft tumors. Transcriptome sequencing and analysis were conducted to determine differential expression genes among various groups.

RESULTS

Compared with the control treatment, P. intermedia treatment significantly promoted tumor growth, invasion, angiogenesis, and metastasis, markedly affected the levels of inflammatory cytokines, and markedly altered M2 macrophages and regulatory T cells (Tregs) infiltration in the tumor microenvironment. However, ABX administration clearly abolished these effects of P. intermedia. Transcriptome and immunohistochemical analyses revealed that P. intermedia infection increased the expression of interferon-stimulated gene 15 (ISG15). Correlation analysis indicated that the expression level of ISG15 was positively correlated with the Ki67 expression level, microvessel density, serum concentrations and tissue expression levels of inflammatory cytokines, and quantities of infiltrated M2 macrophages and Tregs. However, it is negatively correlated with the quantities of infiltrated CD4+ and CD8+ T cells.

CONCLUSION

In conclusion, intratumoral P. intermedia infection aggravated OSCC progression, which may be achieved through upregulation of ISG15. This study sheds new light on the possible pathogenic mechanism of intratumoral P. intermedia in OSCC progression, which could be a prospective target for OSCC prevention and treatment.

[Assessment of mental health status and plasma catecholamine levels in patients with recurrent aphthous ulcer]

PURPOSE

To investigate the relationship between mental health and recurrent aphthous ulcer (RAU), and to explore the change of plasma catecholamine level in RAU patients.

METHODS

Thirty RAU patients treated in Nanjing Stomatological Hospital, Medical School of Nanjing University from February 2016 to August 2016 were selected as the experimental group, and 30 healthy people with matched age and gender were selected as the control group. Patients in both groups were asked to fill in the psychological scales for researchers to analyze their mental state, including Self-Rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS). Whole blood samples were taken from the selected subjects around 9 am to 10 am. High performance liquid chromatography (HPLC) was used to analyze the plasma catecholamine level. Statistical analysis was performed using SPSS 22.0 software package.

RESULTS

The results of SAS and SDS showed that the standard scores of the experimental group were significantly higher than those of the control group (P<0.01), analysis of plasma catecholamine level showed that adrenaline level in the experimental group was significantly higher than the control group (P<0.01). Analysis of the plasma adrenaline level and standard scores of both psychological scales showed that they had significant correlation.

CONCLUSIONS

There is a close relationship between the development of RAU and the mental state of patients. Meanwhile, plasma adrenaline level significantly increases in patients with RAU.

Altered protein profile of plasma extracellular vesicles in oral squamous cell carcinoma development

Extracellular vesicles (EVs) are involved in a wide range of pathological processes and recognized as potential and novel biomarkers for oral squamous cell carcinoma (OSCC). Here, we describe the plasma EV proteome of rats with 4-nitroquinoline-1-oxide (4NQO)-induced OSCC or moderate dysplasia (MD), which can progress to OSCC, by tandem mass tag (TMT)-labeled mass spectrometry. The proteomic profiles suggest the differential expression of various proteins in MD and OSCC, some well-recognized pathological changes (e.g., translation, ATP metabolism, and mesenchymal transition), and some novel pathological changes (e.g., podosome, focal adhesion, and S100 binding). We re-examined the presence of traditional exosomal markers and the reported novel pan-EV markers. In summary, these results suggest potential EV biomarkers and underlying pathological changes in early OSCC as well as the presence of oral-derived EVs in plasma and the need for pan-EV markers. SIGNIFICANCE: This research suggests potential EV biomarkers and underlying pathological changes in early OSCC as well as the presence of oral-derived EVs in plasma and the need for pan-EV markers.

[Use of 2-DE and MALDI-TOF-MS to screen differentially expressed serum proteins in patients with oral lichen planus before and after hydroxychloroquine treatment]

PURPOSE

To establish 2-dimensional gel electrophoresis images and compare the differences of serum proteins of oral lichen planus patients before and after hydroxychloroquine therapy.

METHODS

The serum of oral lichen planus patients before and after hydroxychloroquine therapy were collected, and total protein were extracted. Differential proteome profiles were established and analysed by means of 2-DE and MALDI-TOF-MS. The types and functions of protein were analyzed. SAS 9.12 software package was used for statistical analysis.

RESULTS

Six proteins were well characterized including plasminogen precursor,Apo A-IV precursor, C4A/C4B complement, C2 precursor, Vitamin D binding protein and hypothetical protein. The differences were statistically significant.

CONCLUSIONS

Plasminogen precursor, Apo A-IV precursor, C4A/C4B complement, C2 precursor, Vitamin D binding protein and hypothetical protein are differentially expressed in oral lichen planus patients before and after hydroxychloroquine therapy, but the results need to be validated by other biochemical technologies.

[Study on the invasion of Prevotella intermedia in tissues during carcinogenesis of oral mucosa]

Objective: To explore the differences in bacterial communities within tissues during the process of oral mucosal carcinogenesis, and analyze the relationship between the high-abundance species Prevotella intermedia (Pi) and the occurrence and development of oral mucosal carcinogenesis. Methods: Fresh tissue samples were collected from patients diagnosed with oral leukoplakia (OLK), oral squamous cell carcinoma (OSCC), and healthy controls (HC) at Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Nanjing University, from January 2022 to November 2024, following strict inclusion criteria. Bacterial DNA was extracted from these specimens, and the 2bRAD sequencing for microbiome (2bRAD-M) was employed to analyze and compare the α and β diversity, as well as the community composition of bacteria within tissues, aiming to identify specifically expressed bacteria. Subsequently, paraffin-embedded clinical specimens were collected: 15 cases in the OLK group (including 4 cases of simple hyperplasia, 6 cases of mild dysplasia, and 5 cases of moderate to severe dysplasia), 12 cases in the OSCC group, and 5 cases in the HC group. A 4-nitroquinoline N-oxide (4NQO)-induced OLK progression mouse model was also constructed. Mice were randomly divided into three groups using a random number table, with six in each group. The negative control group was given distilled water to drink; Group 1 was given distilled water containing 4NQO to drink until week 12, while Group 2 was given distilled water containing 4NQO to drink until week 22. After the mice were sacrificed, their tongue tissue were collected and fixed. Fluorescence in situ hybridization (FISH) with specific probes was used to validate the presence of Pi in human and mouse tissue sections, analyzing the correlation between histopathological grading and the invasion depth of Pi. Results: The 2bRAD-M microbial analysis revealed that the relative abundance of Pi in OSCC tissues (10.80%) was significantly higher than in the HC group (0.50%) (P=0.001) and OLK group (0.70%) (P=0.002). FISH probe detection showed that the fluorescence intensity of Pi in human OSCC tissues [123.50 (101.00, 142.30)] was higher than in the HC group [0.00 (0.00, 28.50)], simple hyperplasia OLK [0.00 (0.00, 35.25)], and mild dysplasia OLK [24.50 (0.00, 55.50)] groups, with statistically significant differences respectively (P=0.002, P=0.003, P=0.005). However, there was no significant difference compared to moderate to severe dysplasia OLK [56.00 (28.00, 62.50)] (P=0.210). The fluorescence area of Pi in human OSCC tissues [8 615.00 (7 439.00, 11 084.00)] was significantly larger than in the HC group [0.00 (0. 00, 45.00)], simple hyperplasia OLK group [0.00 (0.00, 81.00)], mild dysplasia [49.00 (0.00, 151.00)], and moderate to severe dysplasia groups [1 450.00 (454.00, 2 892.00)], with highly significant differences (P<0.001). There was a significant correlation between the invasive depth of Pi and the degree of histopathological grading (P<0.001). In mice, the fluorescence intensity of Pi in OSCC tissues [120.00 (110.00, 127.00)] was significantly higher than in the HC group [0.00 (0.00, 12.25)] (P<0.01), but showed no significant difference compared with the OLK group [50.00 (0.00, 58.00)] (P>0.05). The fluorescence area of Pi in mice OSCC tissues [11 020.00 (6 790.00, 12 102.00)] was significantly larger than in the HC group [0.00 (0.00, 56.75)] and the OLK group [0.00 (0.00, 751.50)] (P=0.006, P=0.043). There is a significant correlation between the depth of invasion of Pi and the degree of histopathological grading (P<0.01). Conclusions: This study suggests that Pi in oral mucosal tissue may be a potential biomarker for early detection of OSCC and play an important role in the carcinogenesis process of oral mucosa.

The Promotional Effect of GW4869 on C. albicans Invasion and Cellular Damage in a Murine Model of Oral Candidiasis

Candida albicans (C. albicans) is one of the most common fungi in the human body; it is an opportunistic pathogen and can cause candidiasis. Extracellular vesicles (EVs) derived from the host cells have a potentially protective effect against pathogens and can be developed as vaccine formulations. GW4869 can inhibit the production and release of EVs. Previous studies have indicated that GW4869 can alter the immune and inflammatory responses of the host. However, the effect of GW4869 on Candida infection and the anti-Candida response of the host has not been investigated. We evaluated the effect of GW4869 on C. albicans invasion, biofilm formation, and cellular damage in a murine model of oral candidiasis. In this study, C. albicans-infected mice were injected with or without GW4869. The results proven by macroscopic, microscopic, and ultramicroscopic methods showed that GW4869 treatment exacerbated the oral candidiasis of mice, promoted C. albicans invasion and biofilm formation, and aggravated oral mucosal inflammation and cellular ultrastructural damage. The results are beneficial in the further exploration of the immune mechanism of C. albicans infection.