circFNDC3B Accelerates Vasculature Formation and Metastasis in Oral Squamous Cell Carcinoma.

Emerging evidence has demonstrated that circular RNAs (circRNA) are involved in cancer metastasis. Further elucidation of the role of circRNAs in oral squamous cell carcinoma (OSCC) could provide insights into mechanisms driving metastasis and potential therapeutic targets. Here, we identify a circRNA, circFNDC3B, that is significantly upregulated in OSCC and is positively associated with lymph node (LN) metastasis. In vitro and in vivo functional assays showed that circFNDC3B accelerated the migration and invasion of OSCC cells and the tube-forming capacity of human umbilical vein endothelial cells and human lymphatic endothelial cells. Mechanistically, circFNDC3B regulated ubiquitylation of the RNA-binding protein FUS and the deubiquitylation of HIF1A through the E3 ligase MDM2 to promote VEGFA transcription, thereby enhancing angiogenesis. Meanwhile, circFNDC3B sequestered miR-181c-5p to upregulate SERPINE1 and PROX1, which drove epithelial-mesenchymal transition (EMT) or partial-EMT (p-EMT) in OSCC cells and promoted lymphangiogenesis to accelerate LN metastasis. Overall, these findings uncovered the mechanistic role of circFNDC3B in orchestrating cancer cell metastatic properties and vasculature formation, suggesting circFNDC3B could be a potential target to reduce OSCC metastasis. SIGNIFICANCE: Dual functions of circFNDC3B in enhancing the metastatic ability of cancer cells and promoting vasculature formation through regulation of multiple pro-oncogenic signaling pathways drive lymph node metastasis of OSCC.

Precise extraction of impacted supernumerary tooth in the maxillary anterior region with a digital guide plate: A case report.

RATIONALE: Removal of impacted supernumerary teeth requires precision and accuracy to prevent iatrogenic injury to important anatomical structures during dental surgery and to improve postoperative healing. PATIENT CONCERNS: A 12-year-old girl visited our department for the assessment and management of her deviated front teeth. DIAGNOSIS: Impacted supernumerary tooth extraction in the maxillary anterior region. INTERVENTIONS: The digital guide plate was fabricated after the integration of cone beam computed tomography data with that obtained from scanning the patient's dental model. Impacted supernumerary tooth extraction was performed. OUTCOMES: The use of the digital guide plate and planting instruments made the removal of the impacted supernumerary tooth less invasive, faster, and more accurate, whereas the wound was smaller, and the patient experience more comfortable. LESSONS: Combining the digital guide plate with planting instruments offers a useful aid for the removal of impacted supernumerary teeth among the maxillary anterior region and is, thus, worth promoting.

NOD1 activation promotes cell apoptosis in papillary thyroid cancer.

BACKGROUND: NOD1 can promote or inhibit different types of cancers, suggesting that NOD1 functions in the progression of cancers dependent on the tumour environment. However, the expression and mechanisms of NOD1 during papillary thyroid carcinoma (PTC) progression remain unclear. METHODS: To investigate the role of NOD1 in PTC development and apoptosis, we detected NOD1 expression in three cell lines and surgical specimens from patients with PTC using immunohistochemistry, quantitative real-time PCR (Q-PCR) and Western blotting; we studied the biological functions of NOD1 by loss-of-function analysis of TPC-1 and BCPAP cells and the effect of NOD1 on the progression of PTC in terms of cell proliferation and apoptosis induced by tumour necrosis factor alpha (TNF-α), Fas ligand (Fas L), tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) or Ala-γGlu-diaminopimelic acid (TriDAP) in the presence of cycloheximide (CHX) and determined its underlying molecular mechanism using PTC cell lines in vitro and mouse xenograft models in vivo. RESULTS: Increased expression of NOD1 is correlated with an improved prognosis in thyroid cancer patients. We also found that NOD1 expression was markedly upregulated in PTC cells compared to normal epithelial cells. NOD1 knockdown significantly promoted the proliferation of PTC cells in vitro, while activation of NOD1 signalling promoted PTC cell apoptosis; NOD1-induced apoptosis depends on the activation of caspase-3 and caspase-9 although the RIP2/TAK1 and MAPK pathways in PTC cells. CONCLUSIONS: This study demonstrates that NOD1 is a predictive biomarker for PTC and that PTC cell apoptosis is induced by activation of NOD1 via the RIP2/TAK1 and MAPK pathways. The above results may provide a new perspective on targeting NOD1 signalling for the treatment of PTC, which deserves further investigation.

Mir-5100 Mediates Proliferation, Migration and Invasion of Oral Squamous Cell Carcinoma Cells Via Targeting SCAI.

PURPOSE: We aimed to investigate the role of microRNA-5100 (miRNA-5100) in oral squamous cell carcinoma (OSCC) and its underlying mechanisms.Material/Methods: The expression of miR-5100 and suppressor of cancer cell invasion (SCAI) in OSCC cell lines were examined. A luciferase reporter assay was applied to confirm the combination between miR-5100 and SCAI. Then, miR-5100 inhibitor or small hairpin RNA (shRNA)-SCAI were transfected into cells. Cell Counting Kit-8 assay was executed for testing cell proliferation ability. Flow cytometry assay was exploited for measuring cell cycle. Invasion and migration of OSCC cells were assessed using Transwell assay and wound healing assay. The expression of proteins were detected using western blotting. RESULTS: The results demonstrated that the level of miR-5100 was upregulated while SCAI was downregulated in OSCC cells. SCAI was verified as a direct target of miR-5100. MiR-5100 silencing suppressed proliferation of OSCC cells, increased cells in the G1 and G2 phases, and reduced those in the S phase, which was reversed after transfection with shRNA-SCAI. Moreover, miR-5100 inhibitor downregulated the expression of cyclin-dependent kinase-2 (CDK-2) and cyclinD1, accompanied by upregulation in p27 expression, whereas SCAI silencing had the opposite results. The invasion and migration abilities of OSCC cells were reduced after treatment with miR-5100 inhibitor, whereas SCAI silencing suppressed the effects of miR-5100 inhibitor on OSCC cell behaviors. CONCLUSION: These findings suggested that miR-5100 silencing inhibit proliferation, invasion and migration of OSCC cells via upregulating the expression of SCAI, which provides theoretical basis and treatment strategies for the treatment of OSCC.

MiR-376c-3p targets heparin-binding EGF-like growth factor (HBEGF) to inhibit proliferation and invasion in medullary thyroid carcinoma cells.

INTRODUCTION: Aggressive medullary thyroid carcinomas (MTC) have a high mortality rate and the treatment for patients diagnosed with advanced MTC is comparatively ineffective. We hence aimed to test the effects of miR-376c-3p on MTC and to explore the relevant mechanism. MATERIAL AND METHODS: Cell Counting Kit-8 (CCK-8) and soft agar colony formation assay were applied to evaluate the proliferation of transfected MZ-CRC-1 cells. Wound healing and transwell assay were employed to evaluate MTC cell migration and invasion, respectively. Luciferase assay was performed to validate the downstream target of miR-376c-3p in MZ-CRC-1 cells. Quantitative polymerase chain reaction was used to detect mRNA abundance of key genes. Western blot technique was used to analyze protein levels of HBEGF, E-cadherin, ZO-1, N-cadherin and vimentin. RESULTS: MiR-376c-3p inhibited the viability, migration and invasion of MZ-CRC-1 cells. Moreover, miR-376c-3p mimic downregulated expression of N-cadherin and vimentin but upregulated that of E-cadherin and ZO-1 in MZ-CRC-1 cells. Results for the luciferase reporter assay showed that miR-376c-3p was able to bind the 3' untranslated region of heparin-binding EGF-like growth factor (HBEGF), of which overexpression nearly nullified the miR-376c-3p mimic-induced inhibitory effects in the MTC cells. CONCLUSIONS: MiR-376c-3p showed suppressive effects on MZ-CRC-1 cells via targeting and downregulating HBEGF, suggesting that miR-376c-3p could potentially be targeted for the treatment of MTC.

TLR2 deficiency enhances susceptibility to oral carcinogenesis by promoting an inflammatory environment.

Inflammation is closely related to oral squamous cell carcinoma (OSCC). However, its mechanism is still obscure. Toll-like receptor 2 (TLR2) plays an important role in oral chronic inflammatory diseases, but the role of TLR2 in OSCC is unclear. Here, we investigated the expression of TLR2 expression in OSCCs and examined the potential role of TLR2 in OSCC through its association with clinicopathological features and patient outcome. We used 4-nitroquinoline 1-oxide (4-NQO) to induce a tongue cancer model in TLR2-/- and wild type (WT) mice. Histological and clinical results both indicated that TLR2 played a protective role in oral tumorigenesis. The results of a cytometric bead array (CBA) indicated that TLR2 deficiency resulted in Th1 and Th2 cytokine abnormalities, especially Th2 abnormalities. Immunohistochemistry also showed that TLR2 deficiency increases the number of tongue-infiltrating M2 macrophages. Overall, our results demonstrated that TLR2 plays an important role in the prevention of oral tumorigenesis and affects the levels of Th2 cytokines and tongue-infiltrating M2 macrophages; therefore, it may be used to prevent the development of oral cancer.

High expression of TROP2 is correlated with poor prognosis of oral squamous cell carcinoma.

Human trophoblastic cell-surface antigen 2 (TROP2) is a cell surface glycoprotein that exhibits high expression in various carcinomas but low or no expression in normal tissues. High TROP2 expression plays an important role in promoting tumor development and aggressiveness, which is correlated with reduced patient survival. However, there are few studies regarding TROP2 in relation to both oral squamous cell carcinoma (OSCC) and oral potentially malignant lesions. The expression of TROP2 protein and mRNA was investigated in OSCC tissues, oral potentially malignant lesion tissues, and normal oral tissues using immunohistochemistry and quantitative real-time polymerase chain reaction (qRT-PCR). The association between TROP2 expression and clinicopathological characteristics of OSCC was also analyzed, and the prognostic value of TROP2 was evaluated. The expression of TROP2 protein and mRNA were both higher in OSCC tissues than in oral potentially malignant lesion tissues or normal oral tissues. Positive TROP2 expression was related to differentiation, lymph node metastases, TNM stage, perineural infiltration, and vascular invasion. Poor overall survival was associated with high TROP2 expression and other factors associated with poor overall survival including poor differentiation, lymph node metastasis, TNM stage, vascular invasion, and perineural invasion in univariate analyses. TROP2 expression as well as TNM stage and vascular invasion were independent prognostic factors associated with the overall survival of OSCC patients in multivariate analyses. In summary, High TROP2 expression is associated with poor overall survival and serves as an independent prognostic factor in OSCC. The results suggest that TROP2 expression could be an effective prognostic biomarker for OSCC.