RESUMO
Oral squamous cell carcinoma (OSCC) is a major malignant cancer of the head and neck. Long non-coding RNAs (lncRNAs) have emerged as critical regulators during the development and progression of cancers. This study aimed to identify a lncRNA-related signature with prognostic value for evaluating survival outcomes and to explore the underlying molecular mechanisms of OSCC. Associations between overall survival (OS), disease-free survival (DFS) and candidate lncRNAs were evaluated by Kaplan-Meier survival analysis and univariate and multivariate Cox proportional hazards regression analyses. The robustness of the prognostic significance was shown via the Gene Expression Omnibus (GEO) database. A total of 2,493 lncRNAs were differentially expressed between OSCC and control samples (fold change >2, p < 0.05). We used Kaplan-Meier survival analysis to identify 21 lncRNAs for which the expression levels were associated with OS and DFS of OSCC patients (p < 0.05) and found that down-expression of lncRNA AC012456.4 especially contributed to poor DFS (p = 0.00828) and OS (p = 0.00987). Furthermore, decreased expression of AC012456.4 was identified as an independent prognostic risk factor through multivariate Cox proportional hazards regression analyses (DFS: p = 0.004, hazard ratio (HR) = 0.600, 95% confidence interval(CI) [0.423-0.851]; OS: p = 0.002, HR = 0.672, 95% CI [0.523-0.863). Gene Set Enrichment Analysis (GSEA) indicated that lncRNA AC012456.4 were significantly enriched in critical biological functions and pathways and was correlated with tumorigenesis, such as regulation of cell activation, and the JAK-STAT and MAPK signal pathway. Overall, these findings were the first to evidence that AC012456.4 may be an important novel molecular target with great clinical value as a diagnostic, therapeutic and prognostic biomarker for OSCC patients.
RESUMO
INTRODUCTION: No in vivo study has been reported on the mechanical reinforcement of a tooth after regenerative endodontic treatment (RET). The present work aimed to evaluate the concurrent use of platelet-rich fibrin (PRF) with a blood clot (BC) in RET concerning periapical healing, root development, and tooth structural reinforcement. METHODS: In our study, 24 premolars from 3 beagle dogs were assigned into control, BC, and PRF + BC groups. Periapical healing was monitored with quantitative measurements of root elongation and thickening radiographically. Tooth biomechanical integrity was assessed with the fracture resistance test. Histologic evaluation was conducted. RESULTS: There was a significant difference among the periapical radiolucency decreasing rate of the control (43.75%) and the BC (100%) and PRF + BC (100%) groups (P < .05). The increase of root length and thickness in both the BC and PRF + BC groups was significantly greater than that in the control group (P < .05). No significant difference was detected between the 2 experimental groups regarding periapical healing or root development (P > .05). Teeth in the BC (249.3 ± 64.1 N) and PRF + BC (281.7 ± 37.8 N) groups had significantly higher fracture resistance than those in the control group (108.5 ± 23.3 N) (P < .05). No significant difference was revealed between the BC and PRF + BC groups (P > .05). Histologic evidence of cementumlike tissue deposition along the canal wall with scattered bonelike tissue in the canal was observed. CONCLUSIONS: Either a combination of PRF with BC or BC alone could improve periapical healing, induce root development, and reinforce tooth structure. No additional benefit of PRF to BC in RET was found.
