Exosome-Derived microRNAs from Mouthrinse Have the Potential to Be Novel Biomarkers for Sjögren Syndrome.

Sjögren syndrome (SS) is diagnosed based on invasive tissue biopsies and blood sampling. Therefore, a novel non-invasive and simple inspection diagnostic marker of SS is required. Here, we identified exosome-derived microRNAs (miRNAs) as biomarkers for SS using non-invasive mouthrinse samples collected from patients with SS and healthy volunteers. We compared miRNAs derived from exosomes in mouthrinse samples from the two groups using microarrays and real-time polymerase chain reaction (PCR) and identified 12 miRNAs as biomarker candidates. The expression ratios of four miRNAs were significantly increased in the SS group compared to the control group. Logistic regression analysis revealed a more significant influence of miR-1290 and let-7b-5p in the SS group than that in the control group. We combined these miRNAs to create a diagnostic prediction formula using logistic regression analysis. The combination of miR-1290 and let-7b-5p distinguished SS from the control samples with an AUC, sensitivity, specificity, positive predictive value, and negative predictive value of 0.856, 91.7%, 83.3%, 84.6%, and 90.9%, respectively. These results indicated that an increased ratio of these miRNAs could serve as a novel and non-invasive diagnostic marker for SS. This is the first report of diagnosis and screening of SS by adopting a non-invasive method using mouthrinse.

Detecting Early-Stage Oral Cancer from Clinically Diagnosed Oral Potentially Malignant Disorders by DNA Methylation Profile.

Clinically, early-stage oral cancers are difficult to distinguish from oral potentially malignant disorders (OPMDs), and invasive tissue biopsy should be performed to determine a treatment strategy. Previously, we focused on gargle fluid as a noninvasive testing method and reported aberrant methylation in gargle fluid in patients with oral cancer. This study aimed to distinguish early-stage oral cancer from clinically diagnosed OPMDs using gargle fluid samples. We collected gargle fluid samples from 40 patients who were clinically diagnosed with OPMDs in the training set; among them, 9 patients were pathologically diagnosed with oral cancer. Methylation levels of 25 tumor suppressor genes were analyzed using the methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) method. We found that a combination of six genes (TP73, CASP8, RARB, KLLN, GSTP1, and CHFR) could distinguish oral cancer from clinically diagnosed OPMDs with high diagnostic performance (area under the curve [AUC], 0.885; sensitivity, 77.8%; and specificity, 87.1%). Additionally, the panel comprised of the six methylated genes was validated in the test set. Furthermore, when compared with cytology testing, the panel could accurately detect oral cancer. The present methylated gene panel may serve as a novel biomarker for oral cancer.

Relationship between Oral Hypofunction, and Protein Intake: A Cross-Sectional Study in Local Community-Dwelling Adults.

Few studies have investigated the relationship between nutritional status and comprehensive assessment of oral hypofunction, especially protein intake-related sarcopenia. Thus, we explored these relationships in a large-scale cross-sectional cohort study using the seven-item evaluation for oral hypofunction and Diet History Questionnaire for nutritional assessment. We used the data from 1004 individuals who participated in the 2019 health survey of the residents of Tarumizu City, Kagoshima Prefecture, Japan for analysis. We found that individuals with oral hypofunction were significantly older with a lower skeletal muscle index. Although there were few foods that had a significant difference between the groups with and without oral hypofunction, the consumption of beans and meats was significantly lower in women and men in the oral hypofunction group, respectively. According to the lower limit of the tentative dietary goal defined in Japan, comprehensive evaluation of oral hypofunction was significantly and independently associated with protein intake in both men and women (odds ratio, 1.70; 95% confidence interval, 1.21-2.35). In conclusion, we found that oral hypofunction was associated with targeted protein intake for sarcopenia and frailty prevention in middle-aged and older community-dwelling adults. Comprehensive evaluation of oral function with intervention in cases of hypofunction could inform clinicians to better prevent sarcopenia.

Colorectal Cancer Patients Have Four Specific Bacterial Species in Oral and Gut Microbiota in Common-A Metagenomic Comparison with Healthy Subjects.

Oral microbiota is reportedly associated with gut microbiota and influences colorectal cancer (CRC) progression; however, the details remain unclear. This study aimed to evaluate the role of oral microbiota in CRC progression. Fifty-two patients with CRC and 51 healthy controls were included. Saliva and stool samples were collected, and microbiota were evaluated using 16S rRNA analysis and next-generation sequencing. Comparative analysis was performed on both groups. Linear discriminant analysis effect size (LEfSe) revealed the presence of indigenous oral bacteria, such as Peptostreptococcus, Streptococcus, and Solobacterium spp., at a significantly higher relative abundance in saliva and stool samples of CRC patients compared with controls. Next, CRC patients were divided into early stage (Stage I, II; n = 26; 50%) and advanced stage (Stage III, IV; n = 26; 50%) disease. LEfSe revealed that S. moorei was present at a significantly higher relative abundance in the advanced-stage group compared with the early-stage group, again consistent for both saliva and stool samples. Among bacterial species with significantly higher relative abundance in CRC patients, P. stomatis, S. anginosus, S. koreensis, and S. moorei originated from the oral cavity, suggesting indigenous oral bacteria may have promoted initiation of CRC carcinogenesis. Furthermore, S. moorei may influence CRC progression.

Association of Oral Hypofunction with Frailty, Sarcopenia, and Mild Cognitive Impairment: A Cross-Sectional Study of Community-Dwelling Japanese Older Adults.

Oral hypofunction is a new concept that addresses the oral function of older adults. Few studies have investigated the relationship between oral hypofunction and general health conditions such as frailty, sarcopenia, and mild cognitive impairment. This paper explores these relationships in a large-scale, cross-sectional cohort study. The relationships of oral hypofunction with frailty, sarcopenia, and mild cognitive impairment were examined using data from 832 individuals who participated in the 2018 health survey of the residents of Tarumizu City, Kagoshima Prefecture, Japan. Individuals with frailty, sarcopenia, and mild cognitive impairment had significantly higher rates of oral hypofunction. Frailty was independently associated with deterioration of the swallowing function (odds ratio 2.56; 95% confidence interval, 1.26-5.20), and mild cognitive impairment was independently associated with reduced occlusal force (odds ratio 1.48; 95% confidence interval, 1.05-2.08) and decreased tongue pressure (odds ratio 1.77; 95% confidence interval, 1.28-2.43). There was no independent association found between sarcopenia and oral function. In conclusion, early intervention for related factors such as deterioration of the swallowing function in frailty, reduced occlusal force, and decreased tongue pressure in mild cognitive impairment could lead to the prevention of general hypofunction in older adults.

Circulating microRNA Panel as a Potential Novel Biomarker for Oral Squamous Cell Carcinoma Diagnosis.

A lack of reliable biomarkers for oral squamous cell carcinoma (OSCC) poses a major clinical issue. The sensitivity and specificity of classical serum tumor markers, such as the squamous cell carcinoma antigen (SCC-Ag), are quite poor, especially for early detection. This study aimed to identify specific serum miRNAs potentially serving as OSCC biomarkers. The expression levels of candidate miRNAs in serum samples from 40 OSCC patients and 40 healthy controls were quantitatively analyzed via microarray and reverse transcription PCR (RT-PCR) analyses. To enhance the accuracy of detection, we used Fisher's linear discriminant analysis to establish a diagnostic model that incorporated a combination of selected miRNAs. Consequently, miR-19a and miR-20a were significantly upregulated in the patient group (p = 0.014 and 0.036, respectively), whereas miR-5100 was downregulated (p = 0.001). We found that a combination of six miRNAs (miR-24, miR-20a, miR-122, miR-150, miR-4419a, and miR-5100) could distinguish between OSCC and the control group with a higher degree of accuracy (Area Under the Curve, AUC: 0.844, sensitivity: 55%, and specificity: 92.5%). Furthermore, compared to serum SCC antigen, the 6-miRNA panel could accurately detect the presence of OSCC. The present specific miRNAs panel may serve as a novel candidate biomarker of oral cancer.

Runt-related gene 2 is involved in the inhibition of matrix metalloproteinase-13 expression by roxithromycin in human gingival epithelial cell cultures.

BACKGROUND AND OBJECTIVE: Matrix metalloproteinase (MMP)-13 has wide substrate specificity compared with other MMPs and appears to be involved in periodontitis. Previously, we reported that roxithromycin (RXM) inhibits vascular endothelial growth factor expression induced by tumour necrosis factor-alpha in human periodontal ligament cells, but little is known about the effect of RXM on MMP-13 expression in human gingival epithelial cells. We therefore examined the effect of RXM on MMP-13 mRNA expression and production in cultured human gingival epithelial cells. MATERIAL AND METHODS: Human epithelial cell lines (Ca9-22, TU4, SCCTF and HSC-3) were plated in tissue culture dishes. Then, the culture supernatants and sediments were collected and the production of MMP-13 was analysed using enzyme-linked immunosorbent assay; the expression of MMP-13 mRNA and runt-related gene 2 mRNA was assessed using reverse transcriptase-polymerase chain reaction (RT-PCR) and real-time RT-PCR. We also studied the effect of Runx2 short interfering RNA (siRNA) on the induction of MMP-13. RESULTS: Roxithromycin downregulated the induction of MMP-13 in Ca9-22 cells. Roxithromycin suppressed the expression of MMP-13 mRNA not only in Ca9-22 cells, but also in other human epithelial cell lines. Roxithromycin strongly inhibited the expression of Runx2 mRNA. Furthermore, Runx2 siRNA inhibited the induction of MMP-13 in Ca9-22 cells. CONCLUSION: These results indicate that RXM suppresses MMP-13 via the downregulation of Runx2 in human gingival epithelial cell cultures.

The inhibitory effects of immunosuppressive factors, dexamethasone and interleukin-4, on NF-kappaB-mediated protease production by oral cancer.

Matrix metalloproteinase-9 (MMP-9) produced by tumor cells is known to be implicated in the invasion of squamous cell carcinoma (SCC). In the process of searching for agents to inhibit MMP-9 in cancer, immunosuppressive factors, dexamethasone (DEX) and interleukin-4 (IL-4) were found to inhibit protein production as well as gene expression of MMP-9 in tumor necrosis factor alpha (TNFalpha)-stimulated SCC cells. DEX and IL-4 could also suppress the expression of urokinase type plasminogen activator (uPA) to prevent the conversion from the proenzyme form of MMP-9 to its active form. Regarding their mechanisms to inhibit the expression of MMP-9 and uPA, DEX and IL-4 had no effect on the cell surface levels of TNFalpha receptors, but inhibited the activation of NF-kappaB and NF-kappaB-dependent gene expression. DEX, but not IL-4, could strongly augment the TNFalpha-induced expression of IkappaBalpha in SCC cells. These results suggest that DEX and IL-4 suppress not only immunological reactions, but also tumor invasion by targeting NF-kappaB.