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The molecular mechanisms underlying osteogenic differentiation of periodontal ligament stem cells (PDLSCs) under mechanical tension remain unclear. This study aimed to identify a potential long non-coding ribonucleic acids (lncRNAs)/circular RNAs (circRNAs)-microRNAs (miRNAs)-messenger RNAs (mRNAs) network in mechanical tension-induced osteogenic differentiation of PDLSCs. PDLSCs were isolated from the healthy human periodontal ligament, identified, cultured, and exposed to tensile force. The expression of osteogenic markers was examined, and whole transcriptome sequencing was performed to identify the expression patterns of lncRNA, circRNA, miRNAs, and mRNAs. Enrichment analyses were also performed. Candidate targets of differentially expressed non-coding RNAs (ncRNAs) were predicted, and potential competitive endogenous RNA (ceRNA) networks were constructed by Cytoscape. We found that the osteogenic differentiation of PDLSCs was significantly enhanced under dynamic tension (magnitude: 12%, frequency: 0.7 Hz). Overall, 344 lncRNAs, 57 miRNAs, 41 circRNAs, and 70 mRNAs were differentially expressed in the tension group and the control group. Functional enrichment analysis showed that differentially expressed mRNAs were mainly enriched in osteogenesis-related and mechanical stress-related biological processes and signal transduction pathways (e.g., tumor necrosis factor [TNF] and Hippo signaling pathways). The lncRNA/circRNA-miRNA-mRNA networks were depicted, and potential key ceRNA networks were identified. Our findings may help to further explore the underlying regulatory mechanism of osteogenic differentiation of PDLSCs under mechanical tensile stress.

Purpose Oral lichen planus (OLP) is a potentially malignant condition with unclear etiology. This study aimed to identify potential biomarkers and mechanisms for OLP progression through bioinformatics analyses. Methods Gene Expression Omnibus (GEO) datasets were screened to identify differentially expressed genes (DEGs) between OLP patients and healthy individuals. The functions and enriched pathways of the DEGs were identified. Sequencing dataset GSE70665 was then used to analyze the role of DEGs in the development of OLP to oral squamous cell carcinoma (OSCC). Oncomine and The Cancer Genome Atlas (TCGA) databases were utilized to evaluate clinicopathological characters of OSCC. Univariate and multivariate Cox regression models were used to identify independent prognostic factors. Results A total of 24 DEGs were identified between OLP and normal samples. FAM3B was under-expressed in OLP compared with normal samples and was further significantly downregulated in OSCC compared with OLP. Under-expression of FAM3B was significantly correlated with tumor stage and disease-specific survival (DSS), progression-free interval (PFI) and overall survival (OS) of OSCC patients. With univariate and multivariate Cox regression analysis, FAM3B was an independent prognostic factor. Conclusion Under-expression of FAM3B was associated with the development and malignancy of OLP. FAM3B may serve as a potential prognostic biomarker for OLP.

Purpose The role of periodontal ligament stem cells (PDLSCs) in mediating osteogenesis involved in orthodontic tooth movement (OTM) is well established. However, various relevant in vitro studies vary in the frequency of tension. The effect of tensile frequency on the mechanotransduction of PDLSCs is not clear. The current study aimed to determine the effect of different tensile frequencies on the osteogenic differentiation of PDLSCs and to identify important mechano-sensitivity genes. Methods Human PDLSCs were isolated, identified, and subjected to cyclic equibiaxial tensile strain of 12% at different frequencies of 0.1 Hz, 0.5 Hz, 0.7 Hz, or static cultures. Osteogenic differentiation of PDLSCs was assessed by using Western blotting. High-throughput sequencing was used to identify differential mRNA expression. Short time-series expression miner (STEM) was utilized to describe the frequency patterns of the mRNAs. The functions and enriched pathways were identified, and the hub genes were identified and validated. Results We found that the osteoblastic differentiation capacity of PDLSCs increased with tensile frequency in the range of 0.1–0.7 Hz. Eight frequency-tendency gene expression profiles were identified to be statistically significant. Tensile frequency-specific expressed genes, such as SALL1 and EYA1, which decreased with the increase in tensile frequency, were found. Conclusion The osteoblastic differentiation of PDLSCs under mechanical tensile force is frequency dependent. EYA1 and SALL1 were identified as potential important tensile frequency-sensitive genes, which may contribute to the cyclic tension-induced osteogenic differentiation of PDLSCs in a frequency-dependent manner.

Mechanical stress enhances bone metabolism and periodontal tissue remodelling. 1 The periodontal ligament (PDL) and alveolar bone sense loading stimuli and regulate bone reconstruction, which is the biological basis of orthodontic tooth movement (OTM). 2 These processes involve intricate mechanotransduction, and the turnover rate of the periodontium determines the quantity and quality of OTM. 3 Traditional orthodontic treatment often takes approximately 2 years, and the prolonged duration increases the risk of dental caries, periodontitis, and root resorption. 4 Therefore, researchers are constantly seeking ways to accelerate OTM.The origin of periodontal ligament distraction (PDLD) in accelerating OTM dates back to the end of the 20th century. 5 Studies have