HSP27 promotes vasculogenic mimicry formation in human salivary adenoid cystic carcinoma via the AKT-MMP-2/9 pathway.

PURPOSE: To explore the role and mechanism of heat shock protein 27 (HSP27) in SACC VM formation. STUDY DESIGN: Immunohistochemistry and double staining with cluster of differentiation 31 (CD31) and periodic acid-Schiff (PAS) were used to detect HSP27 expression and VM in 70 SACC tissue samples separately. Quantitative real-time polymerase chain reaction (qRT-PCR), western blot analysis, and immunofluorescence were used to detect gene and protein expression. HSP27 in SACC cells were overexpression or downregulated by transfecting HSP27 or short hairpin RNA target HSP27 (sh-HSP27). The migration and invasion abilities of SACC cells were detected using wound healing and Transwell invasion assays. The VM formation ability of the cells in vitro was detected using a Matrigel 3-dimensional culture. RESULTS: HSP27 expression was positively correlated with VM formation and affected the prognosis of patients. In vitro, HSP27 upregulation engendered VM formation and the invasion and migration of SACC cells. Mechanistically, HSP27 upregulation increased Akt phosphorylation and subsequently increased downstream matrix metalloproteinase 2 and 9 expressions. CONCLUSION: HSP27 may plays an important role in VM formation in SACC via the AKT-MMP-2/9 signalling pathway.

Temporal gene expression profiling during early-stage traumatic temporomandibular joint bony ankylosis in a sheep model.

BACKGROUND: Investigating the molecular biology underpinning the early-stage of traumatic temporomandibular joint (TMJ) ankylosis is crucial for discovering new ways to prevent the disease. This study aimed to explore the dynamic changes of transcriptome from the intra-articular hematoma or the newly generated ankylosed callus during the onset and early progression of TMJ ankylosis. METHODS: Based on a well-established sheep model of TMJ bony ankylosis, the genome-wide microarray data were obtained from samples at postoperative Days 1, 4, 7, 9, 11, 14 and 28, with intra-articular hematoma at Day 1 serving as controls. Fold changes in gene expression values were measured, and genes were identified via clustering based on time series analysis and further categorised into three major temporal classes: increased, variable and decreased expression groups. The genes in these three temporal groups were further analysed to reveal pathways and establish their biological significance. RESULTS: Osteoblastic and angiogenetic genes were found to be significantly expressed in the increased expression group. Genes linked to inflammation and osteoclasts were found in the decreased expression group. The various biological processes and pathways related to each temporal expression group were identified, and the increased expression group comprised genes exclusively involved in the following pathways: Hippo signaling pathway, Wnt signaling pathway and Rap 1 signaling pathway. The decreased expression group comprised genes exclusively involved in immune-related pathways and osteoclast differentiation. The variable expression group consisted of genes associated with DNA replication, DNA repair and DNA recombination. Significant biological pathways and transcription factors expressed at each time point postoperatively were also identified. CONCLUSIONS: These data, for the first time, presented the temporal gene expression profiling and reveal the important process of molecular biology in the early-stage of traumatic TMJ bony ankylosis. The findings might contributed to identifying potential targets for the treatment of TMJ ankylosis.

Oncologic safety of the pedicled submental island flap for reconstruction in oral tongue squamous cell carcinoma: An analysis of 101 cases.

OBJECTIVE: To evaluate whether the pedicle submental island flap (SIF) can be safely used in the oral tongue squamous cell carcinoma (OTSCC) patients with pathologically node-positive (pN+) neck, especially pN+ at level I. METHODS: Retrospectively, 101 OTSCC patients with SIF reconstruction were enrolled. Oncological outcomes included the total locoregional recurrence, the SIF related locoregional recurrence (SRLR) which referred to the local recurrence at flap and ipsilateral neck recurrence at level I, recurrence free survival (RFS), overall survival (OS), and disease specific survival (DSS). RESULTS: Sixty-one patients were pathologically node-negative (pN0) and 40 were pN+. Thirteen patients experienced locoregional recurrence, of which 5 had a SRLR. The pN+ group had a significantly higher locoregional recurrence rate, lower 5-year RFS, OS and DSS than pN0 group (P < 0.05). Patients with pN0 had a significantly higher neck RFS when compared to those with pN+ either at level I (P = 0.005) or at other levels (P < 0.001). However, the neck RFS was similar between the two subgroups of pN+ (P = 0.550). Especially, patients with pN+ at level I had a significantly higher SRLR rate (P = 0.006) compared to those with pN0 at level I. Multivariate analysis showed that pN+ was an unfavorable factor for tumor recurrence and OS. CONCLUSION: Our data did not support the use of SIF in OTSCC patients with pN+ neck at level I due to an significantly increased SRLR rate compared to those with pN0 neck at level I.

Advanced Polymeric Nanoagents for Oral Cancer Theranostics: A Mini Review.

Oral cancer is one of the most common tumours in the world threatening human life and health. The 5-years survival rate of patients with oral cancer has not been improved significantly for many years. The existing clinical diagnostic methods rarely achieve early diagnosis due to deficiencies such as lack of sensitivity. Most of the patients have progressed to the advanced stages when oral cancer is detected. Unfortunately, the traditional treatment methods are usually ineffective at this stage. Therefore, there is an urgent need for more effective and precise techniques for early diagnosis and effective treatment of oral cancer. In recent decades, nanomedicine has been a novel diagnostic and therapeutic platform for various diseases, especially cancer. The synthesis and application of various nanoagents have emerged at the right moment. Among them, polymer nanoagents have unique advantages, such as good stability, high biosafety and high drug loading, showing great potential in the early accurate diagnosis and treatment of tumours. In this review, we focus on the application of advanced polymeric nanoagents in both the diagnosis and treatment of oral cancer. Then, the future therapy strategies and trends for polymeric nanoagents applied to oral cancer are discussed, with the hope that more advanced nanomedical technology will be applied to oral cancer research and promote the development of stomatology.

Unveiling the Differences in Biological Properties of Dental Pulp Stem Cells from Normal and Inflamed Pulp: A Comprehensive Comparative Study.

BACKGROUND The aims of the study were to comprehensively compare the morphology, immunophenotype, proliferation, migration, and regeneration potential of normal dental pulp stem cells (DPSCs) versus inflammatory dental pulp stem cells (iDPSCs). MATERIAL AND METHODS Healthy pulp or inflamed pulp tissue was used to isolate and culture DPSCs and iDPSCs, respectively. These cell populations were characterized by flow cytometry, colony formation assay, transwell assay, and multi-directional differentiation in vitro. RESULTS No difference was observed in the morphology, cell-surface markers, or cell migration between DPSCs and iDPSCs. DPSCs showed a higher colony-forming capacity, proliferative viability, and osteo/dentinogenesis ability compared with iDPSCs. However, iDPSCs demonstrated enhanced neurogenesis, angiogenesis, adipogenesis, and chondrogenesis capacities in comparison to DPSCs. CONCLUSIONS Our data revealed the differences of biological properties between DPSCs and iDPSCs. The highly angiogenic and neurogenic potential of iDPSCs indicate their possible use in the regeneration of the dentin-pulp complex and support the critical role of angiogenesis and neurogenesis in pulp regeneration.

Differences in the biological properties of mesenchymal stromal cells from traumatic temporomandibular joint fibrous and bony ankylosis: a comparative study.

The aim of this study was to compare the functional characteristics of mesenchymal stromal cells (MSCs) from a sheep model of traumatic temporomandibular joint (TMJ) fibrous and bony ankylosis. A sheep model of bilateral TMJ trauma-induced fibrous ankylosis on one side and bony ankylosis on the contralateral side was used. MSCs from fibrous ankylosed callus (FA-MSCs) or bony ankylosed callus (BA-MSCs) at weeks 1, 2, 4, and 8 after surgery were isolated and cultured. MSCs derived from the bone marrow of the mandibular condyle (BM-MSCs) were used as controls. The MSCs from the different sources were characterized morphologically, phenotypically, and functionally. Adherence and trilineage differentiation potential were presented in the ovine MSCs. These cell populations highly positively expressed MSC-associated specific markers, namely CD29, CD44, and CD166, but lacked CD31 and CD45 expressions. The BA-MSCs had higher clonogenic and proliferative potentials than the FA-MSCs. The BA-MSCs also showed higher osteogenic and chondrogenic potentials, but lower adipogenic capacity than the FA-MSCs. In addition, the BA-MSCs demonstrated higher chondrogenic, but lower osteogenic capacity than the BM-MSCs. Our study suggests that inhibition of the osteogenic and chondrogenic differentiations of MSCs might be a promising strategy for preventing bony ankylosis in the future.

Microarray Analysis of Differential Gene Expression Between Traumatic Temporomandibular Joint Fibrous and Bony Ankylosis in a Sheep Model.

BACKGROUND The type of traumatic temporomandibular joint (TMJ) ankylosis depends on the degree of severity of TMJ trauma. Here, we performed comprehensive differential molecular profiling between TMJ fibrous and bony ankylosis. MATERIAL AND METHODS Six sheep were used and a bilateral different degree of TMJ trauma was performed to induce fibrous ankylosis in one side and bony ankylosis in the other side. The ankylosed calluses were harvested at days 14 and 28 postoperatively and analyzed by Affymetrix OviGene-1_0-ST microarrays. DAVID was used to perform the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis for the different expression genes (DEGs). The DEGs were also typed into protein-protein interaction (PPI) networks to get the interaction data. Ten DEGs, including 7 hub genes from PPI analysis, were confirmed by real-time PCR. RESULTS We found 90 and 323 DEGs at least 2-fold at days 14 and 28, respectively. At day 14, bony ankylosis showed upregulated DEGs, such as TLR8, SYK, NFKBIA, PTPRC, CD86, ITGAM, and ITGAL, indicating a stronger immune and inflammatory response and cell adhesion, while genes associated with anti-adhesion (PRG4) and inhibition of osteoblast differentiation (SFRP1) had higher expression in fibrous ankylosis. At day 28, bony ankylosis showed increased biological process related to new bone formation, while fibrous ankylosis was characterized by a prolonged immune and inflammatory reaction. CONCLUSIONS This study provides a differential gene expression profile between TMJ fibrous and bony ankylosis. Further study of these key genes may provide new ideas for future treatment of TMJ bony ankylosis.

Differential regulation of blood vessel formation between traumatic temporomandibular joint fibrous ankylosis and bony ankylosis in a sheep model.

OBJECTIVES: Clinical and experimental studies show that the etiology of traumatic temporomandibular joint (TMJ) fibrous ankylosis and bony ankylosis are associated with the severity of trauma. However, how the injury severity affects the tissue differentiation is not clear. We tested the hypothesis that angiogenesis affects the outcomes of TMJ trauma, and that enhanced neovascularization after severe TMJ trauma would promote the development of bony ankylosis. METHODS: Bilateral condylar sagittal fracture and discectomy were performed for each sheep, with the glenoid fossa receiving either severe trauma to induce bony ankylosis or minor trauma to induce fibrous ankylosis. At days 7, 14, 28, and 56 after surgery, total RNA was extracted from the ankylosed callus. Temporal gene expressions of several molecules functionally important for blood vessel formation were studied by real-time PCR. RESULTS: Histological examination revealed a prolonged hematoma phase and a lack of cartilage formation in fibrous ankylosis. mRNA expression levels of HIF-1α, VEGF, VEGFR2, SDF1, Ang1, Tie2, vWF, CYR61, FGF2, TIMP1, MMP2, and MMP9 were distinctly lower in fibrous ankylosis compared with bony ankylosis at several time points. CONCLUSIONS: Our study indicates that inhibition of angiogenesis after TMJ trauma might be a promising strategy for preventing bony ankylosis in the future.

Removal of the articular fibrous layers with discectomy leads to temporomandibular joint ankylosis.

OBJECTIVE: The aim of this study was to investigate whether direct damage of the articular fibrous layers without condylar fracture, combined with discectomy, was enough to induce temporomandibular joint (TMJ) ankylosis. STUDY DESIGN: Bilateral TMJ surgery was performed in 8 growing sheep. Disk removal (DR) was performed in the lateral two-thirds on the control side, and disk and articular fibrous layers removal (DFLR) was performed in the lateral two-thirds on the experimental side. Four animals were sacrificed for each side at 1 and 3 months postoperatively. RESULTS: Fibrous ankylosis was achieved on the DFLR side in 2 of 4 sheep and fibro-osseous ankylosis in the other 2 sheep at 1 month after surgery. Fibro-osseous ankylosis developed on the DFLR side in 4 sheep at 3 months postoperatively. On the DR side, pathologic characteristics of TMJ osteoarthritis could be seen; however, no evidence of ankylosis was observed. The scores of TMJ ankylosis for the DR side were significantly lower than those for the DFLR side at different time points (P < .05). CONCLUSIONS: This study demonstrated that removal of articular fibrous layers combined with discectomy can lead to traumatic TMJ ankylosis.

Preserving the Fibrous Layer of the Mandibular Condyle Reduces the Risk of Ankylosis in a Sheep Model of Intracapsular Condylar Fracture.

PURPOSE: The aim of this experimental study was to investigate the role of the fibrous layer of the condylar head in the formation of temporomandibular joint (TMJ) ankylosis in a sheep model of intracapsular condylar fracture. MATERIALS AND METHODS: Six growing Xiao-wei Han sheep were used in the study, and bilateral TMJ surgery was performed in each sheep. In the left TMJ, sagittal fracture of the condyle, removal of the fibrous layer of the condylar head, excision of two thirds of the disc, and removal of the fibrous zone of the glenoid fossa were performed. In the right TMJ, the same surgical management was performed, except that in each sheep, the fibrous layer of the condylar head was preserved. Three sheep were killed humanely at 1 month postoperatively, and the other 3 sheep were killed humanely at 3 months postoperatively. The TMJ complexes were examined by histologic evaluation. RESULTS: Fibrous ankylosis was observed on the left side in 3 sheep at 1 month postoperatively and in 2 of 3 sheep at 3 months postoperatively. Fibro-osseous ankylosis was achieved on the left side in 1 sheep at 3 months postoperatively. In the right TMJ, the main postoperative histologic findings included condylar fracture healing, topical rupture or exfoliation of the fibrous layer of the condyle, and fissure between the fibrous layer and the proliferative zone of the condyle. However, no evidence of ankylosis was observed. The TMJ ankylosis scores on the right side were significantly lower than those on the left side at different time points (P < .05). CONCLUSIONS: This study showed that the presence of the fibrous layer of the condylar head prevented the development of TMJ ankylosis in a sheep model of intracapsular condylar fracture.

Current concepts in the pathogenesis of traumatic temporomandibular joint ankylosis.

Traumatic temporomandibular joint (TMJ) ankylosis can be classified into fibrous, fibro-osseous and bony ankylosis. It is still a huge challenge for oral and maxillofacial surgeons due to the technical difficulty and high incidence of recurrence. The poor outcome of disease may be partially attributed to the limited understanding of its pathogenesis. The purpose of this article was to comprehensively review the literature and summarise results from both human and animal studies related to the genesis of TMJ ankylosis.