Characteristics and clinical significance of tertiary lymphoid structures in OSCC.

OBJECTIVES: This study aimed to investigate the characteristics of tertiary lymphoid structures (TLSs) in oral squamous cell carcinoma (OSCC) and their association with clinical and pathological features. MATERIALS AND METHODS: 12 TLS-related chemokines in TCGA database were analyzed to investigate the TLSs in OSCC. The density, maturity, and location of TLSs in a large cohort of 189 OSCC patients (114 of which had clinical and prognostic information) were assessed. And the significance between TLSs and clinicopathologic characteristics was analyzed. RESULTS: Bioinformatics and analysis showed that TLSs were associated with better clinical outcomes in OSCC. Histological staining and analysis showed that the overall survival rate of the high-density group (71/112, 63.4%) was significantly higher (p < 0.0001) than that of the low-density group (41/112, 36.6%), and the high-density group had fewer lymph node metastases (50.0%/68.3%, p = 0.021). And TLSs were divided into 4 types according to the maturity and location. Different types of TLSs are associated with prognosis (OS, p < 0.0001), clinical features (T stage, p = 0.028; degree of differentiation, p = 0.043), and precancerous lesion types (OSF, p = 0.049) of OSCC patients. CONCLUSION: TLSs were closely associated with better OSCC prognosis, and a more systematic classification may better guide the formulation of further treatment options.

The relationship of dietary flavonoids and periodontitis in US population: a cross-sectional NHANES analysis.

OBJECTIVES: We investigated the association between dietary flavonoids intake and periodontitis. MATERIALS AND METHODS: This cross-sectional study analyzed data from the US National Health and Nutrition Examination Survey 2009-2010 on 3025 participants aged between 30 and 80 years who had full-mouth periodontal examination and dietary flavonoids intake data. This study used periodontal pocket depth (PPD) and clinical attachment loss (CAL) as periodontitis markers. Data were analyzed using multivariate linear regression. RESULTS: After adjusting confounders, the middle tertile of total dietary flavonoids was associated with decreased mean PPD (0.06 mm, P = 0.016) and mean CAL (0.13 mm, P = 0.001) and the top tertile of total dietary flavonoids was significantly associated with decreases in mean PPD (0.05 mm, P = 0.029) and mean CAL (0.11 mm, P = 0.010). Both the middle and top tertiles of total flavonoids intake were significantly related with decreased mean CAL in females, those flossing 0 days/week, overweight and non-diabetic population but not in males, smokers, those flossing 1-6 days/week and diabetic population. Higher anthocyanidins, flavones and flavonols intake was significantly associated with decreased mean PPD and mean CAL while higher flavanones intake was only significantly associated with decreased mean CAL. Higher anthocyanidins intake was particularly related with greatest decreases in mean CAL (top tertile: 0.22 mm, middle tertile: 0.17 mm, both P < 0.010). However, no significant associations were found between isoflavones and flavan_3_ols intake and mean CAL. CONCLUSIONS: Higher dietary flavonoids intake may be beneficial for periodontal health. CLINICAL RELEVANCE: Additional anthocyanidins, flavanones, flavones and flavonols intake was associated with improved periodontal health.

5-aminolevulinic acid photodynamic therapy for extensive oral leukoplakia with concomitant oral submucous fibrosis: A case report.

BACKGROUND: Oral leukoplakia and oral submucous fibrosis are potentially malignant disorders of the oral cavity, with high rates of recurrence and malignant transformation. Notably, the malignant transformation rate of oral leukoplakia with concomitant oral submucous fibrosis is significantly higher than that of oral submucous fibrosis or oral leukoplakia alone. However, the management of these conditions is not well defined. Photodynamic therapy is a minimally invasive treatment modality that effectively targets oral potentially malignant disorders, such as oral leukoplakia, erythroleucoplakia, and verrucous hyperplasia, with the advantages of being repeatable and leaving no scarring. CASE PRESENTATION: We report the case of a 42-year-old man with concomitant oral leukoplakia and oral submucous fibrosis almost involving the entire right buccal mucosa, who underwent six sessions of topical 5-aminolevulinic acid-mediated photodynamic therapy. RESULTS: Photodynamic therapy successfully eradicated whitish plaques and improved mouth opening without any adverse effects. Although photodynamic therapy failed to completely reverse the pathological changes, grading of epithelial dysplasia did not progress and clinical recurrence was not found during the 10-month follow-up. CONCLUSION: In conclusion, topical 5-aminolevulinic acid-mediated photodynamic therapy appears safe and has excellent clinical efficacy against oral leukoplakia-concomitant oral submucous fibrosis, but long-term follow-up is necessary.

Prevalence of recurrent aphthous stomatitis, oral submucosal fibrosis and oral leukoplakia in doctor/nurse and police officer population.

BACKGROUND: The doctor/nurse and police officer population have some common typical characteristics of great professional pressure and night shift and past studies indicated oral mucosa lesions were closely associated with psychological factors and health-risking behaviors, however the prevalence of recurrent aphthous stomatitis (RAS) and the two commonly seen oral potentially malignant disorders of oral submucosal fibrosis (OSF) and oral leukoplakia in doctor/nurse and police officer in the Betel quid chewing city of Mainland China is unknown The cross-sectional study was to determine the prevalence differences of RAS, oral leukoplakia and OSF among doctor/nurse, police officer and non-doctor/nurse and non-police officer population aged 20-59 years. METHODS: RAS, OSF and oral leukoplakia were examined in doctor/nurse group (male: 659, female: 2439), police officer group (male: 839, female: 262) and non-doctor/nurse and non-police officer group (male: 7576, female: 8129) from 2020-11-01 to 2021-08-31 in Health Management Center, Xiangya Hospital in Changsha city, Hunan province. RESULTS: The prevalence rates of RAS, OSF, oral leukoplakia and oral leukoplakia combined with OSF in male and female non-doctor/nurse and non-police officer group are 8.32‰ and 10.83‰, 58.08‰ and 1.23‰, 11.75‰ and 0.25‰, 7.66‰ and 0.12‰ respectively. Compared with the non-doctor/nurse and non-police officer population, prevalence rates of RAS in male (24.27‰) and female (20.50‰) doctor/nurse population were significantly higher. Prevalence rates of OSF (21.24‰) and oral leukoplakia (3.03‰) in male doctor/nurse population were significantly less but prevalence rates of OSF (93.71‰), oral leukoplakia (20.17‰) and oral leukoplakia combined with OSF (15.42‰) for male police officer were significantly greater in comparison with male non-doctor/nurse and non-police officer group. OSF and oral leukoplakia prevalence rates were obvious lower for the female than the counterpart male group, but there were no significant differences of OSF and oral leukoplakia prevalence rates between the female non-doctor/nurse and non-police officer and female doctor/nurse group. Oral leukoplakia was not found in the female police officers. CONCLUSIONS: Doctor/nurse population have higher prevalence of RAS. Male doctors/nurses have lower prevalence of OSF and oral leukoplakia, while male police officers have higher prevalence of OSF, oral leukoplakia and oral leukoplakia combined with OSF.

BTC as a Novel Biomarker Contributing to EMT via the PI3K-AKT Pathway in OSCC.

Purpose: Oral squamous cell carcinoma (OSCC) is one of the most common malignant tumors of the head and neck, while metastasis is the main cause of OSCC-related death. There is an urgent need to explore novel prognostic biomarkers and identify biological targets related to metastasis in OSCC treatment. Methods: Analysis of differential expression was performed using datasets in The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Immunohistochemistry (IHC) was conducted to assess the expression of betacellulin (BTC) in OSCC. SCC4 and CAL27 cells were used for in vitro experiments, in which CCK-8, transwell assays, and wounding healing assays were performed to verify the biological functions of BTC. The role of BTC in EMT was analyzed by EMT score and Western blot. Results: Through the analysis of the mRNA expression profile data from TCGA database in OSCC, we found that only low expression of BTC was significantly correlated with a poor prognosis in OSCC patients. The results of IHC assays and TCGA databases showed that the expression level of BTC was related to the tumor stage, histological grade, and metastasis status. In vitro analysis showed that overexpression of BTC significantly suppressed the proliferation and migration of OSCC cells. Furthermore, we confirmed that BTC could affect EMT through the PI3K-AKT signaling pathway. Conclusion: The overexpression of BTC suppresses the proliferation, migration, and EMT of OSCC cells via the PI3K-AKT pathways, leading to a better prognosis in OSCC. BTC may be used as a novel molecular marker to assess the prognosis of OSCC patients.

A regulatory mechanism of a stepwise osteogenesis-mimicking decellularized extracellular matrix on the osteogenic differentiation of bone marrow-derived mesenchymal stem cells.

A cell-derived decellularized extracellular matrix (dECM) plays a vital role in controlling cell functions because of its similarity to the in vivo microenvironment. In the process of stem cell differentiation, the composition of the dECM is not constant but is dynamically remolded. However, there is little information regarding the dynamic regulation by the dECM of the osteogenic differentiation of stem cells. Herein, four types of stepwise dECMs (0, 7, 14, and 21 d-ECM) were prepared from bone marrow-derived mesenchymal stem cells (BMSCs) undergoing osteogenic differentiation for 0, 7, 14, and 21 days after decellularization. In vitro experiments were designed to study the regulation of BMSC osteogenesis by dECMs. The results showed that all the dECMs could support the activity and proliferation of BMSCs but had different effects on their osteogenic differentiation. The 14d-ECM promoted the osteogenesis of BMSCs significantly compared with the other dECMs. Proteomic analysis demonstrated that the composition of dECMs changed over time. The 14d ECM had higher amounts of collagen type IV alpha 2 chain (COL4A2) than the other dECMs. Furthermore, COL4A2 was obviously enriched in the activated focal adhesion kinase (FAK)/phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/protein kinase B (AKT) signaling pathways. Thus, the 14d-ECM could promote the osteogenic differentiation of BMSCs, which might be related to the high content of COL4A2 in the 14d-ECM by activating the FAK/PI3K/AKT signaling pathways.

HNRNPA2B1, as a m6A Reader, Promotes Tumorigenesis and Metastasis of Oral Squamous Cell Carcinoma.

N6-methyladenosine (m6A) modification is the most prevalent modification on eukaryotic RNA, and the m6A modification regulators were involved in the progression of various cancers. However, the functions of m6A regulators in oral squamous cell carcinoma (OSCC) remain poorly understood. In this study, we demonstrated that 13 of 19 m6A-related genes in OSCC tissues are dysregulated, and HNRNPA2B1 was the most prognostically important locus of the 19 m6A regulatory genes in OSCC. Moreover, HNRNPA2B1 expression is elevated in OSCC, and a high level of HNRNPA2B1 is significantly associated with poor overall survival in OSCC patients. Functional studies, combined with further analysis of the correlation between the expression of HNRNPA2B1 and the EMT-related markers from the TCGA database, reveal that silencing HNRNPA2B1 suppresses the proliferation, migration, and invasion of OSCC via EMT. Collectively, our work shows that HNRNPA2B1 may have the potential to promote carcinogenesis of OSCC by targeting EMT via the LINE-1/TGF-ß1/Smad2/Slug signaling pathway and provide insight into the critical roles of HNRNPA2B1 in OSCC.

Potential for treatment benefit of STING agonists plus immune checkpoint inhibitors in oral squamous cell carcinoma.

BACKGROUND: DNA-sensing receptor cyclic GMP-AMP synthase (cGAS) and its downstream signaling effector stimulator of interferon genes (STING) present a novel role in anti-tumor immunity. Recently, the combination of cGAS-STING agonists and immunotherapy achieved promising results in some tumor types. The correlation between cGAS-STING signaling pathway and the tumor immune microenvironment in patients with oral squamous cell carcinoma (OSCC) is unclear. METHODS: We utilized RNA sequencing and clinical data of OSCC patients from the TCGA database to investigate the correlation between cGAS-STING signaling pathway and the tumor immune microenvironment. Six cGAS-STING related genes were obtained from previous studies to establish the enrichment score of cGAS-STING pathway. The differences in survival rate, immune cell infiltration, immune-related genes expression and immune-related biological pathways were studied in the cGAS-STING clusters. RESULTS: We observed a better prognosis of OSCC patients in the cGAS-STING high cluster. The infiltration ratio of immune cells and the expression profiles of immune-related genes were elevated when the cGAS-STING pathway is activated. The differentially expressed genes between high and low cGAS-STING clusters were enriched in immune-related biological pathways. CONCLUSIONS: Our findings suggest the potential benefit of combining STING agonists and immune checkpoint inhibitors in OSCC patients.

Expression profiles of tRNA-derived small RNA and their potential roles in oral submucous fibrosis.

BACKGROUND: Although transfer RNA (tRNA) has been found to be the main source of a rich class of noncoding RNA, the tRNA-derived small RNA (tsRNA) has been proved to play an irreplaceable role in the human body, and its dynamic imbalance could affect the progress of the disease. However, the research on tsRNA in oral submucous fibrosis (OSF) is still scarce. METHODS: We sequenced the OSF and validated it by PCR. We found that there were significant differences in their expression levels in OSF. Furthermore, bioinformatic analysis was performed to explore the roles of these fragments in oral submucous fibrosis. RESULTS: Of 126 tsRNAs in OSF were dysregulated, including 73 upregulated tsRNAs and 53 downregulated tsRNAs. The downregulated tiRNA-Val-CAC-002, tRF-Asn-GTT-005, tRF-Trp-CCA-007 and upregulated tRF-Gly-TCC-016, tRF-Pro-TGG-009 showed significant differences by qRT-PCR validation, which were consistent with the results of RNA sequencing. Gene ontology and pathway analysis revealed that tRF-Gly-TCC-016 would possibly promote the formation and progress of OSF through cytokine-cytokine receptor interaction and cAMP signal pathway, while tiRNA-Val-CAC-002 could be primarily concerned with the transition from OSF to oral squamous cell carcinoma (OSCC). CONCLUSION: tRNA-derived fragments are dysregulated and could be involved in the pathogenesis of oral submucous fibrosis. tRF-Gly-TCC-016 and tiRNA-Val-CAC-002 may be new regulatory molecules that could affect the process of OSF by regulating signal pathways through interacting with multiple genes.

Correlation between vascular endothelial growth factor pathway and immune microenvironment in head and neck squamous cell carcinoma.

BACKGROUND: Immunotherapy is a crucial therapeutic approach in oncology. However, most patients with head and neck squamous cell carcinoma (HNSCC) do not derive benefit from immunotherapy. Vascular endothelial growth factor (VEGF)/VEGF Receptor 2 (VEGFR2) signaling pathway is one of the most important pathways regulating angiogenesis in tumor. The combination of immunotherapy and anti-angiogenic therapy is considered to improve efficacy of immunotherapy. The correlation between VEGF signaling pathway and tumor immune microenvironment in HNSCC patients is unclear. METHODS: We utilized RNA sequencing and clinical data of HNSCC patients from the TCGA database to study the correlation between VEGF signaling pathway and tumor immune microenvironment, on aspect of immune cell infiltration, immune-related gene expression profiling and immune-related biological pathways. RESULTS: We observed that VEGF signaling pathway is positively correlated with immune cell infiltration, immune-related gene expression profiles, and the prognosis of HNSCC patients. The functional enrichment analysis of differentially expressed genes between different VEGF score subtypes detected multiple immune-related biological processes. CONCLUSION: Our findings suggested that combining anti-VEGF signaling pathway agents with immunotherapy, such as immune checkpoint inhibitors (ICI) therapy, may exhibit encouraging benefits in HNSCC.

Prognostic Value of an Immune-Related Gene Signature in Oral Squamous Cell Carcinoma.

The prognosis and immunotherapy response rates are unfavorable in patients with oral squamous cell carcinoma (OSCC). The tumor microenvironment is associated with tumor prognosis and progression, and the underlying mechanisms remain unclear. We obtained differentially expressed immune-related genes from OSCC mRNA data in The Cancer Genome Atlas (TCGA) database. Overall survival-related risk signature was constructed by univariate Cox regression analysis and LASSO Cox regression analysis. The prognostic performance was validated with receiver operating characteristic (ROC) analysis and Kaplan-Meier survival curves in the TCGA and Gene Expression Omnibus (GEO) datasets. The risk score was confirmed to be an independent prognostic factor and a nomogram was built to quantify the risk of outcome for each patient. Furthermore, a negative correlation was observed between the risk score and the infiltration rate of immune cells, as well as the expression of immunostimulatory and immunosuppressive molecules. Functional enrichment analysis between different risk score subtypes detected multiple immune-related biological processes, metabolic pathways, and cancer-related pathways. Thus, the immune-related gene signature can predict overall survival and contribute to the personalized management of OSCC patients.

Biological information and functional analysis reveal the role of discoidin domain receptor 1 in oral squamous cell carcinoma.

OBJECTIVES: This study aimed to establish a framework for the role of discoidin domain receptor 1 (DDR1) in oral squamous cell carcinoma (OSCC) through biological data and functional analysis. STUDY DESIGN: The GSE31056 series of the Gene Expression Omnibus database and UALCAN website were used to assess DDR1 expression in head and neck squamous cell carcinoma (HNSCC) and OSCC. DDR1 RNA sequencing data for 260 HNSCC samples from The Cancer Genome Atlas were overlaid to evaluate its association with tumor progression and prognosis. To identify the function of DDR1 in OSCC, 38 patients with OSCC were followed for 8 years and immunohistochemical analysis, western blotting, Cell Counting Kit-8, and colony formation assays were conducted on OSCC cell lines to reveal DDR1 expression and function. RESULTS: DDR1 was overexpressed in HNSCC and OSCC tumor specimens and its expression correlated with overall survival and T-stage classification (P = .049, P = .0316). Furthermore, DDR1 was related to OSCC tumor growth because its expression increased with the T-stage level (P = .0071) but not N-stage level, histologic stage, or recurrence (P > .05). DDR1 was highly expressed in OSCC cell lines and promoted cell proliferation, which was repressed by nilotinib (P < .05). CONCLUSIONS: DDR1 has an oncogenic role in OSCC and might be a novel target for anti-OSCC therapy.

Use of artificial intelligence to recover mandibular morphology after disease.

Mandibular tumors and radical oral cancer surgery often cause bone dysmorphia and defects. Most patients present with noticeable mandibular deformations, and doctors often have difficulty determining their exact mandibular morphology. In this study, a deep convolutional generative adversarial network (DCGAN) called CTGAN is proposed to complete 3D mandibular cone beam computed tomography data from CT data. After extensive training, CTGAN was tested on 6 mandibular tumor cases, resulting in 3D virtual mandibular completion. We found that CTGAN can generate mandibles with different levels and rich morphology, including positional and angular changes and local patterns. The completion results are shown as tomographic images combining generated and natural areas. The 3D generated mandibles have the anatomical morphology of the real mandibles and transition smoothly to the portions without disease, showing that CTGAN constructs mandibles with the expected patient characteristics and is suitable for mandibular morphological completion. The presented modeling principles can be applied to other areas for 3D morphological completion from medical images.Clinical trial registration: This study is not a clinical trial. Patient data were only used for testing in a virtual environment. The use of the digital data used in this study was ethically approved.

Role of the arecoline/YAP1/BMP4 pathway in promoting endothelial-mesenchymal transition in oral submucous fibrosis.

BACKGROUND: Oral submucous fibrosis (OSF) is a potentially malignant lesion characterized by epithelial-mesenchymal transition (EMT). Bone morphogenetic protein 4 (BMP4) promotes EMT in fibrotic diseases, but the underlying mechanisms and its potential role in OSF are unclear. This study investigates whether BMP4 plays a role in the pathogenesis of OSF and explores the underlying mechanisms. METHODS: The expression of BMP4 and the EMT proteins E-cadherin and vimentin was investigated in OSF specimens by immunohistochemical staining. Pearson's correlation analysis was conducted to explore the correlation between BMP4 and the EMT markers. Western blotting and RT-PCR assays were used to analyze the effect of arecoline (a known EMT-promoting pathogenic factor in OSF) on BMP4 and identify the transcription factor involved. Confocal microscopy was used to observe the intracellular sublocalization of the identified transcription factor, Yes-associated protein 1 (YAP1). Finally, siRNA silencing of BMP4 was used to determine its effect on YAP1 activation and arecoline-induced EMT. RESULTS: BMP4 is overexpressed in OSF and plays a role in EMT, as its expression correlates with the expression of E-cadherin and vimentin. Arecoline induces BMP4 expression via the activation of YAP1 (through its nuclear translocation). Furthermore, the YAP1/BMP4 mechanism is the main molecular event in arecoline-induced EMT, as knockdown of BMP4 expression affects expression of the EMT markers and inhibits extracellular matrix accumulation. CONCLUSIONS: Arecoline induces EMT in OSF via the YAP1/BMP4 pathway. Thus, BMP4 could be considered as a potential therapeutic target for the treatment of OSF.

In Vitro Experimental Study of the Effect of Adjusting the Guide Sleeve Height and Using a Visual Direction-Indicating Guide on Implantation Accuracy.

PURPOSE: We used a single-variable method to analyze the influence of the guide sleeve height of a conventional template on implantation accuracy in vitro and improve the function of short-sleeve templates by adding a visual direction-indicating guide (VDING). MATERIALS AND METHODS: We created 100 copies of a volunteer's dentition plaster model. The normal template (NT) and the VDING template (VT) were made with guide sleeves 2, 5, 8, and 10 mm in height. Additionally, a freehand (FH) group and a group with an FH-based visual guide were used. Simulated implantation in an emulated head model was performed in each group. After surgery, cone-beam computed tomography images of the plaster were used for registration, and the accuracy was compared among the groups. RESULTS: When the NT sleeve height was 5 mm or less, increased deviation was found, and the results for some of the accuracy indicators were not different from those in the FH group. The accuracy of sleeves 5 mm or less in height was better in the VT group than in the NT or FH group. CONCLUSIONS: Use of the NT with a guide sleeve height of 5 mm or less can introduce large deviations in implantation, which can be prevented by the VT. However, the use of the VDING alone was not sufficient.

Influence of in vitro differentiation status on the in vivo bone regeneration of cell/chitosan microspheres using a rat cranial defect model.

The aim of this study was to investigate the influence of the in vitro osteogenic differentiation status on the in vivo bone regeneration of cell/chitosan microspheres qualitatively and quantitatively. To this end, rat bone-marrow-derived mesenchymal stromal cells (BMSCs) were seeded onto apatite-coated chitosan microspheres. The constructs were osteogenically differentiated for 0, 7, 14, and 21 days followed by calvarial defect implantation in vivo for up to 8 weeks. In vitro studies showed that BMSCs in the constructs proliferated from day 0 to day 7. The activity and gene expression of alkaline phosphatise increased from day 0 to day 14 and then decreased. The gene expression of collagen type I and osteocalcin peaked at day 21. In vivo, constructs retrieved from day 0 group were filled with fibrous tissues and capillaries, but no bone formation was observed. Constructs retrieved from day 7 and day 21 groups showed progressive bone formation, whereas those retrieved from day 14 group had the highest percentage of bone formation. These data suggested that to generate a substantial amount of bone in vivo, not only the in vitro osteogenic differentiation was necessary, but also the period of pre-differentiation was important for the cell-scaffold constructs. The period of pre-differentiation for 14 days was found to be the most suitable for chitosan microspheres.

[Clinical analysis for oral mucosal disease in 21 972 cases].

OBJECTIVE: 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.

Altered Gray-Matter Volumes Associated With Betel Quid Dependence.

Betel quid (BQ) is one of the most commonly consumed psychoactive substances. It has been suggested to be associated with various health issues, especially oral cancer. Evidence also points to possible decreased cognitive functions after long-term BQ chewing, such as attention and inhibition control. The present study aims to investigate the brain structure basis of BQ chewing in Hunan province of China. Twenty-five BQ chewers and 25 controls were recruited to participate in this study. Voxel-based morphormetry analysis revealed that there were three key regions showing structural differences between BQ chewers and controls, including bilateral dorsolateral prefrontal cortex (DLPFC)/insula, ventral medial prefrontal cortex, and left orbitofrontal cortex. Moreover, the GMV in the DLPFC could potentially predict BQ dependence scores, level of daily BQ chewing, and history of BQ chewing. These results suggested that participants who showed BQ chewing dependence may have deficit in inhibition control and affective decision-making, and the level of deficit was dependent on the level of daily BQ chewing, and history of BQ chewing. Understanding the neurobiology features of BQ chewing would help us develop novel ways to diagnose and prevent BQ dependence.

[Bactericidal effects and smear layer removal of Er:YAG-laser radiation against Enterococcus faecalis in root canals].

OBJECTIVE: To evaluate the cleaning ability of Er:YAG laser against Enterococcus faecalis in root canals.
 Methods: The single-rooted human teeth were sterilized and inoculated with Enterococcus faecalis and were randomly assigned into 2 groups. A group of teeth was irrigated with saline during root canal preparation while another group with NaClO. After mechanical preparation, the two groups were randomly divided into 3 subgroups according to the different treatments: Samples, laser radiation, and calcium hydroxide intracanal medication for 7 days. Bactericical effects were compared among groups. Root canal walls and dental tubules were observed under scanning electron microscope.
 Results: Er:YAG laser was the most efficient way for anti-bacteria among the groups (P<0.05), but there was no significant difference between the 2 laser groups (P>0.05). Meanwhile the smear laser was efficiently removed by laser compared with other treatments, and the laser could open the dentinal tubules.
 Conclusion: Er:YAG laser can be effectively used for root canal disinfection without NaClO and Ca(OH)2.

Quantitative proteomic analysis for novel biomarkers of buccal squamous cell carcinoma arising in background of oral submucous fibrosis.

BACKGROUND: In South and Southeast Asian, the majority of buccal squamous cell carcinoma (BSCC) can arise from oral submucous fibrosis (OSF). BSCCs develop in OSF that are often not completely resected, causing local relapse. The aim of our study was to find candidate protein biomarkers to detect OSF and predict prognosis in BSCCs by quantitative proteomics approaches. METHODS: We compared normal oral mucosa (NBM) and paired biopsies of BSCC and OSF by quantitative proteomics using isobaric tags for relative and absolute quantification (iTRAQ) to discover proteins with differential expression. Gene Ontology and KEGG networks were analyzed. The prognostic value of biomarkers was evaluated in 94 BSCCs accompanied with OSF. Significant associations were assessed by Kaplan-Meier survival and Cox-proportional hazards analysis. RESULTS: In total 30 proteins were identified with significantly different expression (false discovery rate < 0.05) among three tissues. Two consistently upregulated proteins, ANXA4 and FLNA, were validated. The disease-free survival was negatively associated with the expression of ANXA4 (hazard ratio, 3.4; P = 0.000), FLNA (hazard ratio, 2.1; P = 0.000) and their combination (hazard ratio, 8.8; P = 0.002) in BSCCs. CONCLUSION: The present study indicates that iTRAQ quantitative proteomics analysis for tissues of BSCC and OSF is a reliable strategy. A significantly up-regulated ANXA4 and FLNA could be not only candidate biomarkers for BSCC prognosis but also potential targets for its therapy.