[Application of 3D printing technology under three-dimensional reconstruction in mandibular reconstruction].

PURPOSE: To explore the application value of 3D printing technology under three-dimensional reconstruction in mandibular reconstruction. METHODS: Eighty-four patients with mandibular defect reconstruction were divided into two groups by different operation methods: 3D group(n=42) and control group(n=42). Patients in the control group underwent routine operation, while patients in the experimental(3D) group underwent three-dimensional reconstruction with 3D printing technology. The operation conditions, incidence of complications, recovery of facial features and occlusal relationship were recorded. SPSS 23.0 software package was used for statistical analysis of the data. RESULTS: The operation time of 3D group was significantly shorter than that of the control group, and the amount of bleeding was significantly less than that of the control group(P<0.05). The recovery rate of facial appearance and occlusal relationship in 3D group was significantly higher than in the control group(95.24% vs 78.57%, P<0.05). Compared with the control group, the movement distance of mandibular points in 3D group was significantly smaller before and after operation(P<0.05). The satisfaction scores of chewing function and pronunciation recovery in the two groups were close(P>0.05), but compared with the control group, the satisfaction scores of appearance recovery in the 3D group were significantly higher(P<0.05). CONCLUSIONS: 3D reconstruction under 3D printing technology can reduce intraoperative bleeding, shorten the operation duration, and achieve good shape recovery with high degree of satisfaction.

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.

[Effect of mi-138 targeting PLD2 gene on proliferation and migration of oral cancer cells].

PURPOSE: To investigate the effect of miR-138 targeting PLD2 gene on proliferation and migration of oral cancer cells. METHODS: After oral cancer cells were transfected with miR-138, the expression level of microRNA-138 was detected by RT-PCR assay, the proliferation ability was detected by MTT assay, and cell cycle distribution was detected by flow cytometry. Transwell migration assay was used to detect cell migration ability, Western blotting assay was used to detect the expression levels of MMP-9, PLD2 and cyclin D1 in gastric cancer cells. Luciferase assay was used to report the targeting relationship between microRNA-138 and PLD2 gene. SPSS 21.0 software package was used to analyze the data. RESULTS: After miR-138 was transfected into oral cancer cells, the relative expression level of miR-138 was 4.28±0.16, which was significantly higher than that of blank control and miR-NC group (P<0.05). Luciferase reporter gene assay showed that the relative activity of PLD2 wild plasmid luciferase was significantly lower in oral cancer cells transfected with microRNA-138 than in other groups (P<0.05); The expression level of PLD2 gene in miR-138 group was significantly lower than that in blank control group and miR-NC group (P<0.05). After oral cancer cells were transfected with miR-138, the proliferation ability of oral cancer cells in miR-373 group was significantly lower than that in control group and miR-NC group (P<0.05). Flow cytometry showed that the ratio of G0/G1 phase was (64.39±6.49)% in the group of miR-138, which was significantly higher than that in the blank control group and the group of miR-NC(P<0.05); The ratio of S phase in the group of miR-138 was(13.28±3.16)%, which was significantly lower than that in the blank control group and the group of miR-NC (P<0.05); There was no significant difference in the ratio of G2/M phase among the groups (P>0.05). Transwell experiment showed that the number of migrating cells transfected with miR-138 in oral cancer cells was 138.46±24.37, which was significantly lower than that in blank control group and miR-NC group(P<0.05). Western blotting experiments showed that the relative levels of MMP-9, vimentin and cyclin D1 in the miR-138 group were 0.14±0.04, 0.17±0.02 and 0.15±0.03, respectively, which were significantly lower than those in the blank control group and the miR-NC group(P<0.05). CONCLUSIONS: miR-138 can target PLD2 gene expression and inhibit the proliferation and migration of oral cancer cells.

Anatomical study and clinical application of medial sural artery perforator flap for oral cavity reconstruction.

The present study aims to provide anatomical evidence for clinical application of the medial sural artery perforator (MSAP) flap. The current study investigated the vascular anatomy of the flap, evaluated the postoperative appearance and function of the donor and recipient sites, and investigate the clinical value in reconstruction of oral cavity. Six lower limbs of Chinese adult cadavers were microsurgically dissected. The locations and courses of the medial sural artery perforators were identified and recorded, which provided an anatomical basis for clinical application. Then, 16 clinical cases employing this flap were evaluated, ranging from 3×4cm to 6×8cm, and were employed for defects in the oral cavity region. Sixteen clinical cases with intraoral soft tissue defects, which included four clinical cases with inner cheek defects, were successfully followed up for 10-47 months (24 months on average). The donor site function, contour of recipient site and oral function recovery were evaluated as acceptable or better in cases with intraoral soft tissue defect, which were further verifying the value of clinical application of MSAP in repairing oral cavity defects. Moreover, two typical clinical cases were described in detail. To conclude, the MSAP flap is a favorable choice for small- to medium-size defects based on minor donor site morbidity, satisfactory oral function recovery, perforator stability and adaptation of the pedicle for anastomosis in the oral cavity region.

MiR-34a inhibits the proliferation, migration, and invasion of oral squamous cell carcinoma by directly targeting SATB2.

In various kinds of carcinomas, the special AT-rich sequence-binding protein 2 (SATB2) with its atypical expression promotes the metastasis and progression of the tumor, though in the oral squamous cell carcinoma (OSCC) its inherent mechanism and the status of SATB2 remain unclear. The role played by the SATB2 expression in the OSCC cell lines and tissue samples in the target of miR-34a downstream is the intended endeavor of this study. In te OSCCs the miR-34a expression was determined by quantitative real-time polymerase chain reaction (q-PCR), while the SATB2 expression in the cell lines and tissue samples in OSCC was analyzed with the q-PCR and the western blot. Studies in both in vitro and in vivo of the effects of miR-34a on the initiation of OSCC were conducted. As a direct target of the miR-34a the SATB2 was verified with the luciferase reporter assay. In cases where the miR-34a levels were low, the SATB2 in OSCCs seemed to be overexpressed. Besides, both in the in vitro and in vivo a suppression of migration, invasion, and cell growth was caused by miR-34a by down regulating the SATB2 expression. The SATB2 being a direct target of miR-34a was confirmed by the cotransfection of miR-34a mimics specifically the decrease in the expression of luciferase of SATB2-3'UTR-wt reporter. As a whole, our study confirmed the inhibition of miR-34a in the invasion, proliferation, and migration of the OSCCs, playing a potential tumor suppressor role with SATB2 as its downstream target.

FOXM1 is a novel predictor of recurrence in patients with oral squamous cell carcinoma associated with an increase in epithelial­mesenchymal transition.

Although forkhead box protein M1 (FOXM1) is markedly upregulated in human premalignant and oral squamous cell carcinoma (OSCC) tissues and cultured cells, the association of FOXM1 expression with OSCC prognosis is not well understood. The present study investigated the possible association of FOXM1 expression in patients with OSCC with their clinicopathological characteristics and clinical outcomes. The expression of FOXM1 protein in OSCC tissues from 119 patients was evaluated by immunohistochemistry, and the results demonstrated that FOXM1 overexpression in patients with OSCC was associated with tumour recurrence and poor prognosis. To study the in vitro effects of FOXM1, its expression was decreased by small interfering RNA (siRNA) in OSCC cell lines, and FOXM1 knockdown decreased the proliferative, migratory and invasive capacities of cells. FOXM1 inhibition by siRNA gave rise to reduced expression of vimentin and increased expression of E­cadherin. The present study reported FOXM1 as a novel predictor of tumour recurrence in patients with OSCC and its potential involvement in epithelial­mesenchymal transition in OSCC cells.

[Expression and correlation of HPV16E6 and tumor suppressor gene p53 in oral squamous cell carcinoma].

PURPOSE: To exploring the expression of PV16E6 gene and p53 gene in patients with oral carcinoma and the correlation between pathological grade and clinical stage of oral cancer and expression of HPV16E6 gene and p53 gene. METHODS: One hundred and seventy-three cases of oral cancer, 98 cases of oral precancerous lesions and 79 cases of peri-cancerous normal tissue were selected. The expression of HPV16E6 and p53 was detected by immunohistochemistry. The data were analyzed using SPSS 21.0 software package. RESULTS: In oral carcinoma, the expression rate of HPV16E6 was 81.5% (141/173), the expression rate of p53 was 23.7% (41/173); in oral precancerous lesions, the expression rate of HPV16E6 was 39.8% (39/98), the expression rate of p53 was 57.1% (56/98); in peri-cancerous normal tissues, the expression rate of HPV16E6 was 2.5%(2/79), the positive expression rate of p53 was 89.9%(71/79). There was significant difference in the positive expression rate of p53 and HPV16E6 among 3 groups. The expression of HPV16E6 in oral cancer was significantly higher than in the other two groups(P<0.05); the expression rate of p53 in oral cancer was significantly lower than the other two groups. In addition, with the advance of clinical stage and pathological grade, the positive expression rate of HPV16E6 increased gradually, while the positive expression rate of p53 was significantly decreased (P<0.05). CONCLUSIONS: HPV16E6 protein and p53 protein may play an important role in the occurrence and progress of oral cancer.

Monocarboxylate transporter 4 facilitates cell proliferation and migration and is associated with poor prognosis in oral squamous cell carcinoma patients.

Monocarboxylate transporter 4 (MCT4) is a cell membrane transporter of lactate. Recent studies have shown that MCT4 is over-expressed in various cancers; however, its role in cancer maintenance and aggressiveness has not been fully demonstrated. This study investigated the role of MCT4 in oral squamous cell carcinoma (OSCC), and found that it is highly expressed in OSCC patients by using immunohistochemistry. Moreover, this over-expression of MCT4 was closely associated with tumor size, TNM classification, lymphatic metastasis, distant metastasis and tumor recurrence, and also poor prognosis. To further study mechanisms of MCT4 in vitro, we used small-interfering RNA to silence its expression in OSCC cell lines. The results showed that knock-down of MCT4 decreased cell proliferation, migration, and invasion. The inhibition of proliferation was associated with down-regulation of p-AKT and p-ERK1/2, while decreased cell migration and invasion may be caused by down-regulation of integrin ß4-SRC-FAK and MEK-ERK signaling. Together, these findings provide new insight into the critical role of MCT4 in cell proliferation and metastasis in OSCC.