CircHLA-C: A significantly upregulated circRNA co-existing in oral leukoplakia and oral lichen planus.

BACKGROUND: Oral leukoplakia (OLK) and oral lichen planus (OLP) are common precancerous lesions of the oral mucosa. The role of circular RNAs (circRNAs) in OLK and OLP is unclear. The aim of this study was to evaluate the circRNA expression profiles of OLK and OLP, and further explore the potential role of circRNAs in the pathogenesis of these two diseases. METHODS: High throughput sequencing technology was performed to detect the differentially expressed circRNA in OLK (n = 6), OLP (n = 6), oral squamous cell carcinoma (n = 6), and normal oral mucosa tissues (n = 6). Expression of selected circRNAs was validated by qRT-PCR, enzyme tolerance assay, and Sanger sequencing. Expanded sample size validation was done in 20 tissue pairs. The biological processes and signal pathways involved in differential circRNA were analyzed by GO and KEGG enrichment. TargetScan and MiRanda were used to predict miRNAs downstream of circRNA and draw competitive endogenous RNA network diagram. RESULTS: Forty-nine circRNAs were significantly altered in OLK and OLP, including 30 upregulated and 19 downregulated circRNAs. The five selected circRNAs were validated by qRT-PCR, Sanger sequencing, and RNase R assay. GO and KEGG analyses indicated that the upregulated circHLA-C may be involved in the biological process of immune function of OLK and OLP. Bioinformatics analysis indicated that circHLA-C may be involved in the progression of OLK and OLP as a ceRNA. In validation with expanded sample size, PCR results showed that circHLA-C expression was significantly upregulated in OLK and OLP. ROC analysis indicated that circHLA-C has potential diagnostic value with good accuracy and specificity. CONCLUSION: Our study revealed that circHLA-C is the most significantly upregulated circRNA co-existing in OLK and OLP, and we preliminarily discuss the role of circHLA-C in the etiopathogenesis and progression of OLK and OLP.

Expression profile of circular RNAs in oral lichen planus.

BACKGROUND: This study sought to identify the circular RNAs (circRNAs) differentially expressed in oral lichen planus (OLP) to investigate the possible role of circRNAs in this disease's pathogenesis. METHODS: Six OLP and six normal oral mucosal tissues were used for circRNA detection and sequencing. 10 selected circRNAs were verified by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). A gene ontology (GO) functional analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to predict the functions of circRNAs in OLP. TargetScan and miRanda were applied to predict targeted micro (mi)RNAs and messenger (m)RNAs of circRNAs, and competing endogenous (ce)RNA networks were mapped. RESULTS: One hundred and thirty-five circRNAs were identified differentially expressed in OLP tissues compared to normal control tissues, including 83 upregulated circRNAs, and 52 down-regulated circRNAs. RT-qPCR confirmed that 10 circRNAs were all abnormally expressed in OLP. The GO functional analysis and KEGG pathway analysis showed that differentially expressed circRNAs were involved in 535 GO functional items and 78 signal pathways. A ceRNA network analysis showed that circRNAs might interact with a variety of miRNAs. CONCLUSIONS: This study mapped the expression profile of abnormally expressed circRNAs in OLP tissues for the first time and showed that circRNAs appear to play an important role in the pathogenesis of OLP.

Serum metabolite profiling of a 4-Nitroquinoline-1-oxide-induced experimental oral carcinogenesis model using gas chromatography-mass spectrometry.

BACKGROUND: Oral cancer progresses from hyperplastic epithelial lesions through dysplasia to invasive carcinoma. The critical needs in oral cancer treatment are expanding our knowledge of malignant tumour progression and the development of useful approaches to prevent dysplastic lesions. This study was designed to gain insights into the underlying metabolic transformations that occur during the process of oral carcinogenesis. METHODS: We used gas chromatography-mass spectrometry (GC-MS) in conjunction with multivariate statistical techniques to observe alterations in serum metabolites in a 4-Nitroquinoline 1-oxide (4NQO)-induced rat tongue carcinogenesis model. Thirty-eight male rats were randomly divided into two groups, including the 4NQO-induced model group of 30 rats and the healthy control group of five rats. Animals were sacrificed at weeks 9, 13, 20, 24, and 32, post-4NQO treatment. Tissue samples were collected for histopathological examinations and blood samples were collected for metabolomic analysis. Partial least squares discriminate analysis (PLS-DA) models generated from GC-MS metabolic profile data showed robust discrimination from rats with oral premalignant and malignant lesions induced by 4NQO, and normal controls. RESULTS: The results found 16 metabolites associated with 4NQO-induced rat tongue carcinogenesis. Dysregulated arachidonic acid, fatty acid, and glycine metabolism, as well as disturbed tricarboxylic acid (TCA) cycle and mitochondrial respiratory chains were observed in the animal model. The PLS-DA models of metabolomic results demonstrated good separations between the 4NQO-induced model group and the normal control group. CONCLUSION: We found several metabolites modulated by 4NQO and provide a good reference for further study of early diagnosis in oral cancer.

Prevalence of and related risk factors in oral mucosa diseases among residents in the Baoshan District of Shanghai, China.

BACKGROUND: Oral mucosal diseases (OMDs) encompass a variety of different types of diseases. Our aim was to evaluate the prevalence and related risk factors of OMDs among residents in the Baoshan District of Shanghai, China, and provide a scientific basis for prevention and control strategies. METHODS: A sample of 653 residents aged 17 to 92 years from the Baoshan community was investigated in 2014. Each resident was surveyed by questionnaire to evaluate their oral mucosa and oral mucosa examinations were conducted. We followed up with 607 residents in 2018. All data were statistically analyzed using the SPSS 25.0 software package (Chicago, IL, USA) at the general population, gender and age levels. A X2 test was used to compare rates of risk factors and logistic regression analysis was used to detect the correlation between disease and risk factors. RESULTS: The prevalence rate of OMDs was found to be 9.19%-9.56% (2014-2018). The most common OMDs were atrophic glossitis (1.84%), recurrent aphthous ulcer (RAU, 1.68%), burning mouth syndrome (BMS, 1.38%), oral lichen planus (OLP, 1.23%) and traumatic ulcers (1.23%). The prevalence of RAU and BMS in different age groups was significantly different. Tobacco and alcohol use and psychological factors in the OMDs group were higher than the no-OMDs group. Systemic diseases including diabetes mellitus (DM) was significantly relevant to OLP. CONCLUSION: Age, tobacco and alcohol use, and psychological factor correlated strongly with the occurrence and development of OMDs, and they should be the focus of primary prevention. General epidemiological studies suggested that OLP was closely related to DM.

Dynamic changes in the gene expression profile during rat oral carcinogenesis induced by 4-nitroquinoline 1-oxide.

The typical progression of oral cancer is from hyperplastic epithelial lesions through dysplasia to invasive carcinoma. It is important to investigate malignant oral cancer progression and development in order to determine useful approaches of prevention of dysplastic lesions. The present study aimed to gain insights into the underlying molecular mechanism of oral carcinogenesis by establishing a rat model of oral carcinogenesis using 4­nitroquinoline 1­oxide. Subsequently, transcription profile analysis using an integrating microarray was performed. The dynamic gene expression changes of the six stages of rat oral carcinogenesis (normal, mild epithelial dysplasia, moderate dysplasia, severe dysplasia, carcinoma in situ and oral squamous cell carcinomas) were analyzed using component plane presentations (CPP)­self­organizing map (SOM). Six genes were verified by quantitative polymerase chain reaction, immunohistochemistry and succinate dehydrogenase (SDH) activity assay kit. Numerous differentially expressed genes (DEGs) were identified during rat oral carcinogenesis. CPP­SOM determined that these DEGs were primarily enriched during cell cycle, apoptosis, inflammatory response and tricarboxylic acid cycle, indicating the coordinated regulation of molecular networks. In addition, the expression of specific DEGs, such as janus kinase 3, cyclin­dependent kinase A­1, B­cell chronic lymphocytic leukaemia/lymphoma 2­like 2, nuclear factor­κB, tumor necrosis factor receptor superfamily member 1A, cyclin D1 and SDH were identified to have high concordance with the results from microarray data. The current study demonstrated that oral carcinogenesis is a multi­step and multi­gene process, with a distinct pattern alteration along a continuum of malignant transformation. In addition, this comprehensive investigation provided a theoretical basis for the understanding of the molecular alterations associated with oral carcinogenesis.

Metabolic transformation of DMBA-induced carcinogenesis and inhibitory effect of salvianolic acid b and breviscapine treatment.

Oral cancer typically develops from hyperplasia through dysplasia to carcinoma with a multistep process of carcinogenesis involving genetic alterations resulting in aberrant cellular appearance, deregulated cell growth, and carcinoma. The metabolic transformation during the process of oral carcinogenesis and its implications for cancer therapy have not been extensively investigated. Here, we report a metabonomic study on a classical model of 7,12-dimethylbenz(a)anthracene (DMBA)-induced oral carcinogenesis in hamsters to delineate characteristic metabolic transformation during the carcinogenesis using gas chromatography time-of-flight mass spectrometry (GC-TOF MS). Salvianolic acid B (Sal-B), isolated from Salvia miltiorrhiza Bge, and Breviscapine, a flavonoid isolated from Herba Erigerontis, were used to treat the hamsters exposed to DMBA to investigate the molecular mechanism of the inhibitory effect of the two agents on oral carcinogenesis. The dynamic changes of serum metabolic profiles indicated that both Sal-B and Breviscapine were able to attenuate DMBA-induced metabolic perturbation, which is consistent with the histopathological findings that Sal-B and Breviscapine significantly decreased the squamous cell carcinoma (SCC) incidence in the two treatment groups. Significant alterations of key metabolic pathways, including elevated glutaminolysis and glycolysis, and decreased cholesterol and myo-inositol metabolism, were observed in the DMBA-induced model group, which were attenuated or normalized by Sal-B or Breviscapine treatment. Elevated inflammation and tumor angiogenesis at gene and metabolite expression levels were also observed in DMBA-induced oral dysplasia and SCC but were attenuated or normalized by Sal-B and Breviscapine along with significantly decreased incidences of SCC formation.

[Study of oral precancerous lesion and oral cancer by using micro PET/CT].

PURPOSE: To study oral precancerous lesion and oral cancer by using micro PET/CT. METHODS: Thirty-nine SD rats were divided into experimental group and control group. 33 of them were raised with a 4-nitroquinoline-1-oxide (4NQO) solution with the concentration of 0.002% during the first 13 weeks, and then changed to normal water. The other 6 rats drank normal water all the time. During 25th to 30th week of the experiment, 2-Deoxy-2-[F-18]fluoro-D-glucose (FDG)-PET/CT was performed for these rats. One day after imaging, pathological examination was performed. SUVmax and T/NT were investigated according to pathological results. SAS6.0 software package was used for statistical analysis. RESULTS: There was no significant difference in SUVmax among the normal group, precancerous group and cancerous group (P>0.05). There was significant difference in T/NT(muscle, brain) between the normal group and the cancerous group (P<0.05). But there was no significant difference between the normal group and the precancerous group (P>0.05); and no significant difference between the precancerous group and the cancerous group (P>0.05). The T/NT (muscle, brain) ratios increased along with the increase of the pathologic grade of the lesions. There was no significant difference in T/NT(thyroid) among the three groups and no correlation between the T/NT(thyroid) ratios and the pathologic grade. CONCLUSIONS: Micro PET/CT, as a non-invasive technology, may contribute to the dynamic studies of the process of carcinogenesis. T/NT(muscle, brain) ratios could show the degree of lesions of rat's tongue during carcinogenesis.

[Clinical survey of the association between stress and periodontitis].

PURPOSE: To investigate the effects of stress on periodontitis. METHODS: 44 chronic periodontitis patients and 42 patients with healthy periodontal tissues(as control) were enrolled in the study. All subjects were required to complete a questionnaire which was mainly made up of the symptom checklist 90. Data collected included clinic parameters, psychological factors, life events and basic socio-demographics. The results were statistically assessed by SPSS 10.0 software. RESULTS: There was significant difference between periodontitis group and the control group in education, marital status, and life events (P<0.05 or P<0.01). Compared with the controls, the periodontitis patients got higher scores in somatization, obsessive-compulsive, interpersonal sensitivity, depression, anxiety, hostility, the impact of sleep and diet (P<0.05 or P<0.01). In periodontitis group, there was significant correlation between CPITN, CI and depression, anxiety, interpersonal sensitivity, etc. (P<0.01 or P<0.05). CONCLUSIONS: In this sample, there was a close association between stress and periodontitis. Stress may be a significant risk indicator for periodontitis.

[The effect of stress on periodontitis model of guinea pigs].

OBJECTIVE: To investigate the effect of stress on Guinea Pigs' periodontitis model. METHODS: 24 periodontitis models of guinea pigs were provided by inoculating Actinobacillus actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) in the gingival sulcus. The guinea pigs were divided into two groups: stress group(stimulated with cold bath and fright) and control group(without stimulations). Three animals of each group were sacrificed successively at 1, 2, 4, 6 week after inoculation. Clinical and histological evaluation, cortisol concentration examinations, osteoclast and osteoblast numbers account were applied. RESULTS: The cortisol concentration of stress group was significantly higher than that of control group at 1, 2, 4 week after stressed(P < 0.05 or P < 0.01). Pocket depth in stress group was significantly deeper than that in control group at 2, 4 week (P < 0.05), Compared with control group, the stress group demonstrated more active tissue damage and alveolar bone resorption. The bone repair in stress group was not as active as in control group. The osteoclast numbers in stress group was significantly higher than that in control group at 1, 4, 6 week (P < 0.05). CONCLUSIONS: Stress could enhance the destruction of periodontal tissues infected by pathogenic bacteria and increase disease susceptibility. It was concluded that stress was a significant risk indicator for periodontitis.

[Analysis of pathogenic relations between dental caries and periodontitis].

OBJECTIVE: In order to search the cause of dental caries and periodontitis. METHODS: Selected 70 patients with severe chronic periodontitis (CP group) and 50 patients with caries sensitivity (CS group) in clinical adults of oral medicine (18 to 50-year-old) during 1 year. Parameters of oral hygiene, caries and periodontitis were recorded in the typical groups of CP and CS. RESULTS: The patients of CP group had rare caries, DFS in the groups of CP and CS was 1.46+/-2.60 and 17.32+/-7.55 respectively(p<0.001),while the patients of CS group had relative periodontal health indeed, CPTNI in CS and CP groups were 0.98+/-0.63 and 3.24+/-0.62 respectively (p<0.001), and the number of missing teeth was 1.90+/-3.34 and 1.10+/-1.85 respectively(p>0.05). 3 patients(only 2.4%)confirmed the parameters of caries sensitive as well as severe periodontitis. CONCLUSION: The correlating pathogenesis of caries and periodontitis seems to have antiagonism tendency. The ecological connection and bacterial interaction are worthy of further study.