[Applied anatomical characteristics of vascularized iliac muscle flap and its clinical application in repairing oral and maxillofacial defects].

PURPOSE: To investigate the feasibility and safety of the deep circumflex iliac artery (DCIA) derived chimeric flap through the anatomical study of the blood vessels and perforating branches in the ilioinguinal region, and to provide the basis for selecting different DCIA chimeric flap schemes according to the difficulty of surgery, defect conditions and repair needs. METHODS: Six Chinese adult specimens were dissected by retrograde perfusion of red latex into bilateral femoral arteries. At the same time, the length, diameter and main branch position of DCIA vascular pedicle were measured in 12 lower limb CTAs, and compared with the anatomical data. Six patients with oral tumors accompanied by mandibular defects who were treated in the Department of Oral and Maxillofacial Surgery, Affiliated Stomatological Hospital of Nanjing Medical University from July 2020 to November 2021 were repaired and reconstructed with the chimeric iliac myofascial flap. The postoperative appearance and occlusal function of the recipient area were observed. SPSS 19.0 software package was used for data analysis. RESULTS: A total of 19 DCIA perforators with an external diameter of ≥ 0.5 mm were found in 12 specimens of ilioinguinal region. These perforators were distributed in the 5 cm×3 cm area, inside the ilium and 5cm behind the anterior superior iliac spine. The length of DCIA vascular pedicle was (6.73±1.06) cm. The measured value of the external diameter of the starting position of the vascular pedicle was (2.55±0.29) mm. The outer diameter of DCIA skin perforator penetrating deep fascia was (1.12±0.14) mm. In the CTA analysis of 12 lower limbs, it was found that the length of DCIA vascular pedicle was (6.98±0.62) cm. The measured diameter at the original position of vascular pedicle was (2.35±0.20) mm. Six cases of mandibular defects were repaired with iliac internal oblique fascia mosaic flap. Six cases of lliac flap survived successfully after operation. Follow up for 6 to 24 months (average 12 months) showed that the mandibular shape and function recovered well, the intraoral myofascial flap became mucosal, and the implanted iliac bone showed no significant volume change on CT after operation. Walking and weight bearing in donor area were basically normal, and no abdominal hernia occurred. CONCLUSIONS: DCIA and its main branches have a relatively constant course and distribution in the ilioinguinal region. According to the conditions of different defect areas, different tissue types of chimeric flaps based on DCIA can be prepared to meet the repair requirements. The donor site complications can be controlled, and it is an ideal choice to repair mandibular defects.

Metabolomic Analysis Reveals that SPHK1 Promotes Oral Squamous Cell Carcinoma Progression through NF-κB Activation.

BACKGROUND: Metabolic disorders are significant in the occurrence and development of malignant tumors. Changes of specific metabolites and metabolic pathways are molecular therapeutic targets. This study aims to determine the metabolic differences between oral squamous cell carcinoma (OSCC) tissues and paired adjacent noncancerous tissues (ANT) through liquid chromatography-mass spectrometry (LC-MS). SPHK1 is a key enzyme in sphingolipid metabolism. This study also investigates the potential role of SPHK1 in OSCC. MATERIALS AND METHODS: This study used LC-MS to analyze metabolic differences between OSCC tissues and paired ANT. Principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) were applied to explain the significance of phospholipid metabolism pathways in the occurrence and development of OSCC. Through further experiments, we confirmed the oncogenic phenotypes of SPHK1 in vitro and in vivo, including proliferation, migration, and invasion. RESULTS: The sphingolipid metabolic pathway was significantly activated in OSCC, and the key enzyme SPHK1 was significantly upregulated in oral cancer tissues, predicting poor OSCC prognosis. In this study, SPHK1 overexpression was associated with high-grade malignancy and poor OSCC prognosis. SPHK1 targeted NF-κB by facilitating p65 expression to regulate OSCC tumor progression and promote metastasis. CONCLUSIONS: This study identified metabolic differences between OSCC and paired ANT, explored the carcinogenic role of overexpressed SPHK1, and revealed the association of SPHK1 with poor OSCC prognosis. SPHK1 targets NF-κB signaling by facilitating p65 expression to regulate tumor progression and promote tumor metastasis, providing potential therapeutic targets for diagnosing and treating oral tumors.

In vitro experimental study on the formation of microRNA-34a loaded exosomes and their inhibitory effect in oral squamous cell carcinoma.

Studies have shown the inhibitory effect of microRNA-34a on proliferation, migration, and invasion of oral squamous cell carcinoma. However, the lack of a safe and effective delivery system limits the clinical application of microRNA-34a in oral cancer treatment. An exosome is a small extracellular vesicle that mediates intercellular communication by delivering proteins, nucleic acids, and other contents, and functions as a natural drug delivery carrier. Here, we aimed to explore whether exosomes could be used to load microRNA-34a via co-incubation and further used to treat OSCC. Ultracentrifugation was used to obtain exosomes derived from HEK293T cells and the extracted exosomes were analyzed via transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and Western blotting. Subsequently, we loaded cholesterol-modified microRNA-34a into HEK293T cell exosomes by co-incubation. Then, PKH67 and Cy3 co-labeled exo-microRNA-34a were co-incubated with HN6 cells and exosome entry into the HN6 cells was observed using a confocal laser scanning microscope. The cell proliferation, migration, and invasion were assessed by CCK-8 and Transwell assay analysis. SATB2 expression in HN6 cells was analyzed via western blotting. In this study, cholesterol-modified microRNA-34a was loaded into exosomes of HEK293T cells by co-incubation. The microRNA-34a-loaded exosomes were secreted from HEK293T cells and were absorbed by HN6 oral squamous carcinoma cells. Further, microRNA-34a-loaded exosomes led to a significant inhibition of HN6 cell proliferation, migration, and invasion by down regulating SATB2 expression. These results report a new delivery method for microRNA-34a, providing a new approach for the treatment of oral cancer.

Exosomal microRNA-23b-3p promotes tumor angiogenesis and metastasis by targeting PTEN in salivary adenoid cystic carcinoma.

MicroRNA (miR)-23b-3p is known to target various genes that are involved in cancer-related pathways. Exosomes are emerging intercellular communication agents. Exosomes secreted by cancer cells can deliver active molecules to the surrounding stromal cells, thereby influencing the recipient cells and promoting the development of cancers. However, the role of exosomal miR-23b-3p in salivary adenoid cystic carcinoma (SACC) is not yet clear. In this study, we set out to investigate the potential role of cancer-derived exosomal miR-23b-3p-related phosphatase and tensin homolog deleted on chromosome 10 in the alteration of angiogenesis and vascular permeability in SACC. We investigated the effect of exosomal miR-23b-3p on the progression of SACC. In vitro experiments indicated that exosomal miR-23b-3p led to an upregulation of vascular permeability, and reduced expression of tight junction proteins. In addition, exosomal miR-23b-3p also enhanced angiogenesis and migration. Next, the angiogenic effect of exosomal miR-23b-3p was validated in vivo, as it led to an increase in the tumor microvasculature. Furthermore, the growth rate of SACC was faster after injection of exosomes loaded with cholesterol-modified miR-23b-3p in mice. In conclusion, these results revealed that SACC cell-derived exosomes play an important role in promoting angiogenesis and local vascular microleakage of SACC by transporting miR-23b-3p, which suggests that miR-23b-3p in the exosomes may be a potential biomarker for distant metastasis of SACC. This suggests the potential of a novel therapeutic target by delivering anti-miR-23b-3p that focuses on exosomes.

Follistatin-like 1 suppresses osteoblast differentiation of bone marrow mesenchymal cells during inflammation.

OBJECTIVE: The current study aimed to explore the effect of Follistatin-like 1 (FSTL1) on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in an inflammatory environment. DESIGN: Animal models of FSTL1-deficiency and wild-type mice were used, and the micro-CT images of the femoral head were evaluated. Mouse bone marrow mesenchymal stem cells were treated with various concentrations of recombinant FSTL1 (rFSTL1) in an inflammatory environment in vitro. Meanwhile, overexpression or knockdown of FSTL1 through lentiviral transfection was performed. Alkaline phosphatase (ALP) activity was tested, and Alizarin Red staining (ARS) was performed to evaluate osteogenic differentiation ability. The mRNA expression level of osteogenesis-related genes was detected by RT-qPCR. RESULTS: In vivo experiments revealed a higher number of femoral skulls, higher trabecular thickness, smaller trabecular space, and less osteoporosis in FSTL1-knockdown mice than in the wild-type mice. The BMSCs with overexpression of FSTL1 or those treated with recombinant FSTL1 (rFSTL1) showed suppression of ALP activity, calcium nodule formation, and expression of osteogenesis-related genes osteopontin (OPN), osteocalcin (OCN), collagen type I alpha 1 (Col1α1), and more importantly, rFSTL1 functions in a dose-dependent manner. In contrast, FSTL1 knockdown promoted the osteogenesis activity and the expression of these osteogenesis-related genes in vitro. CONCLUSIONS: FSTL1 is an osteogenic suppressor that inhibits the osteogenic differentiation of BMSCs during inflammation and it can be a new target for bone regeneration.

Identification of pivotal microRNAs involved in the development and progression of salivary adenoid cystic carcinoma.

BACKGROUND: miRNAs and mRNAs have been significantly implicated in tumorigenesis and served as promising prognostic biomarkers for human cancer. Hence, this study was aimed to develop the pivotal miRNA biomarkers-based prognostic signature for salivary adenoid cystic carcinoma. METHODS: The miRNA and mRNA expression data were integrated from the gene expression omnibus database to study their involvement in salivary adenoid cystic carcinoma development and progression. Gene ontology and kyoto encyclopedia of genes and genomes were conducted to analyze the biological pathways. Reverse transcription-quantitative PCR was used to verify the expression of selected miRNAs in salivary adenoid cystic carcinoma and corresponding normal tissues. RESULTS: There were 386 differentially expressed genes: 158 upregulated and 228 downregulated genes and 102 differentially expressed miRNAs: 78 upregulated and 24 downregulated miRNAs in the salivary adenoid cystic carcinoma samples. A miRNA-mRNA network containing 11 miRNAs and 199 genes was subsequently constructed. Gene ontology and Kyoto encyclopedia of genes and genomes enrichment analysis revealed that the genes targeted by the 11 miRNAs were mostly involved in tumor-related pathways and processes, such as miRNAs in cancer, focal adhesion, neurotrophin signaling pathway, and the PI3K-Akt signaling pathway. Among them, 4 miRNAs (miR-375, miR-494, miR-34c-5p, and miR-331-3p) were selected to verify by reverse transcription-quantitative PCR in 36 pairs of collected salivary adenoid cystic carcinoma and adjacent nontumor samples. Overall survival analysis revealed that the higher expression of miR-331-3p was significantly associated with a worst overall survival and multivariate Cox regression analysis suggested that hsa-miR-331-3p could be an independent prognostic factor for salivary adenoid cystic carcinoma. CONCLUSION: Our results revealed that 4-miRNAs signature was a powerful prognostic biomarker for salivary adenoid cystic carcinoma, which provide a basis for exploring deeper mechanisms regarding the progression of salivary adenoid cystic carcinoma, and leading to the development of potential therapeutic strategies.

Sphk1 promotes salivary adenoid cystic carcinoma progression via PI3K/Akt signaling.

The progression of salivary adenoid cystic carcinoma (SACC) is closely related to abnormal gene expression. Herein, the role of Sphk1 in SACC was explored. Sphk1 was overexpressed in SACC tissues. In SACC cell lines, Sphk1 induced cell proliferation, inhibited apoptosis, and promoted cell migration. Moreover, Sphk1 overexpression induced up-regulation of the PI3K protein level and AKT phosphorylation level. Rescue assays further showed that activation of the Sphk1 /PI3K/Akt pathway affected various biological functions of SACC cells. Together, these findings suggested that Sphk1 promotes salivary tumorigenesis by activating the PI3K/ Akt pathway, which may provide novel intervention targets for SACC treatment.

Evaluation of autofluorescence visualization system in the delineation of oral squamous cell carcinoma surgical margins.

INTRODUCTION: Delineating the margins of Oral squamous cell carcinoma (OSCC) is a critical step for optimaltumor resection. The aim of this study was to evaluate the accuracy of lesion surgical margin identification using autofluorescence visualization. MATERIALS AND METHODS: Thirty patients with OSCC were included in this study. For each lesion, the fluorescence loss boundary was determined using VELscope before ablative surgical resection (with a 1.5-2cm safety margin) was performed. A total of 126 samples were obtained from 30 surgical specimens, each containing the tissue from the fluorescence loss boundary to surgical margin. The status of each sample was determined by oral pathologists and the staining intensities of Ki-67, E-cadherin, and Vimentin at the fluorescence loss boundary and surgical margin were evaluated by immunohistochemistry. RESULTS: Fluorescence loss regions were identified in all patients. Of the 126 samples collected, HE staining identified 77 normal epithelia (61.1%), 26 mild dysplasia (20.6%), 17 severe dysplasia (13.4%) and 6 carcinomas in situ (4.9%). A significant correlation was found between the differentiation grade of tumor cells and the pathological status of the surgical marginal specimens (P<0.05). Forty-two of the 126 samples were randomly selected for further immunohistochemical staining. No significant differences were seen in Ki-67, E-cadherin, or Vimentin expression at the fluorescence loss boundary or surgical margin, however, the proteins' expression level was positively correlated with the degree of dysplasia (P<0.01). CONCLUSION: Autofluorescence visualization has potential as a simple surgical margin setting device for OSCC and may help delineate the superficial area of OSCC with acceptable accuracy. However, when considering the inherent limitations of this system, we suggest that the approach should only be applied under certain conditions, such as when dealing with superficial, well-differentiated lesions.

SATB2 overexpression promotes oral squamous cell carcinoma progression by up-regulating NOX4.

While atypical expression of special AT-rich sequence-binding protein 2 (SATB2) has been approved associated with tumor progression, metastasis and unfavourable prognosis in various carcinomas. However, in oral squamous cell carcinoma (OSCC), both the expressive state and associated functions of SATB2's are still undefined. Here we show that, in clinical samples from a retrospective cohort of 58 OSCC patients, high expression of SATB2 is associated with poor prognosis of OSCC patients. In this study, we investigated SATB2 is highly expressed in OSCC tissues and cell lines, which can promote OSCC cells' proliferation, migration, invasion and tumor growth. According to sequencing results based on previous literature, we identified NOX4 is a bona fide downstream target of SATB2, when it was knockdown, OSCC's proliferation can be partially suppressed. Furthermore, NOX4 knockdown inhibits tumorigenicity, which can be rescued partially by ectopic expression of SATB2 in HNSCC cell line, and vice versa. Collectively, our findings not only indicate overexpression of SATB2 triggers the proliferative, migratory and invasive mechanisms which are important in the malignant phenotype of OSCC, but also identify NOX4 as the downstream gene for SATB2. These findings indicate that SATB2 may play a key role in OSCC tumorigenicity and may be a future target for the development of new therapeutic regimens.