Identification of hub genes and transcription factors involved in periodontitis on the basis of multiple microarray analysis.

OBJECTIVES: To identify the differentially expressed genes (DEGs) during the pathogenesis of periodontitis by bioinformatics analysis. METHODS: GEO2R was used to screen DEGs in GSE10334 and GSE16134. Then, the overlapped DEGs were used for further analysis. g:Profiler was used to perform Gene Ontology analysis and pathway analysis for upregulated and downregulated DEGs. The STRING database was used to construct the protein-protein interaction (PPI) network, which was further visua-lized and analyzed by Cytoscape software. Hub genes and key modules were identified by cytoHubba and MCODE plug-ins, respectively. Finally, transcription factors were predicted via iRegulon plug-in. RESULTS: A total of 196 DEGs were identified, including 139 upregulated and 57 downregulated DEGs. Functional enrichment analysis showed that the upregulated DEGs were mainly enriched in immune-related pathways including immune system, viral protein interaction with cytokine and cytokine receptor, cytokine-cytokine receptor interaction, leukocyte transendothelial migration, and chemokine receptors bind chemokines. On the contrary, the downregulated DEGs were mainly related to the formation of the cornified envelope and keratinization. The identified hub genes in the PPI network were CXCL8, CXCL1, CXCR4, SEL, CD19, and IKZF1. The top three modules were involved in chemokine response, B cell receptor signaling pathway, and interleukin response, respectively. iRegulon analysis revealed that IRF4 scored the highest. CONCLUSIONS: The pathogenesis of periodontitis was closely associated with the expression levels of the identified hub genes including CXCL8, CXCL1, CXCR4, SELL, CD19, and IKZF1. IRF4, the predicted transcription factor, might serve as a dominant upstream regulator.

[Shanghai municipal expert consensus on standardized prevention and control of COVID-19 during procedures of oral radiology].

The announcement of National Health Commission on January 20, 2020 (No.1 of 2020) has included novel coronavirus pneumonia into the B class infectious diseases according to the law of the People's Republic of China on the prevention and control of infectious diseases, and has been managed as A class infectious diseases. People's governments at all levels and health administration departments have been paying high attention to it. With the alleviation of COVID-19 nationwide, dental clinics gradually resume to work. The main transmission routes of COVID-19 are respiratory droplets and contact transmission, hence oral radiological examination is kind of a high-risk operation. Standardized radiologic process is of great significance to reduce the risk of COVID-19 transmission. In accordance with the national and Shanghai epidemic prevention requirements, and in combination with the actual situation of various medical institutions, Oral and Maxillofacial Radiology Committee of Shanghai Stomatological Association formulated the expert consensus on standardized prevention and control of COVID-19 for clinical reference. This recommendation will be updated according to the situation of epidemic prevention and control in China and the new relevant diagnosis and treatment plans.

[Experimental study on the feasibility of low-dose cone beam computed tomography scanning].

OBJECTIVE: The effects of different tube currents and voltages on image quality and radiation dose were studied to provide a theoretical basis for low-dose cone beam computed tomography (CBCT) scanning in children. METHODS: Different tube currents and voltages were used to scan the incisor area of fresh Bama pig heads by CBCT. The radiation dose was recorded, and image quality was evaluated. RESULTS: As the tube current or voltage decreased, the radiation dose and image quality gradually decreased. The computed tomographic dose index (CTDIvol) of 90 kV, 2.5 mA and 60 kV, 7.0 mA were all 1.7 mGy. The image quality score of the former was higher than that of the latter, and the difference between them was statistically significant (P<0.05). CONCLUSIONS: Low-dose CBCT scanning appears to be able to reduce the necessary tube current during imaging by improving image quality.

Antitumor effects of WNT2B silencing in GLUT1 overexpressing cisplatin resistant head and neck squamous cell carcinoma.

OBJECTIVES: The increased rate of glucose uptake necessary to support the growth of tumor cells is mediated by glucose transporters, and glucose transporter 1 (GLUT1) is overexpressed in several types of cancer in correlation with poor prognosis. And WNT2B overexpression is thought to be involved in tumor progression. Here, we investigated the effects of WNT2B in GLUT1 overexpressing cisplatin resistant head and neck squamous cell carcinoma (HNSCC) in vitro and in vivo. MATERIALS AND METHODS: We generated GLUT1 overexpressing cisplatin resistant CAL27 and SCC25 oral cancer cells. Lentiviral mediated knock-down of WNT2B was performed in CAL27 and SCC25. QRT-PCR and Western blot analysis were used to detect the mRNA and protein expression of GLUT1, WNT2B, Cyclin D1 and ß-catenin. Cell viability was assessed by MTT analysis. Colony formation assay was performed by staining with 0.5% crystal violet. The role of WNT2B in HNSCC was examined in vivo through the generation of a CAL27 (or cisplatin resistant CAL27 or cisplatin resistant CAL27 with WNT2B knock-down) nude mice xenograft model of HNSCC. RESULTS: Knock-down of WNT2B in decreased cell viability and colony formation in cisplatin resistant CAL27 and SCC25 in association with the downregulation of GLUT1, cyclin D1 and ß-catenin. In a cisplatin resistant CAL27 mouse xenograft model, shRNA mediated silencing of WNT2B increased survival and decreased tumor growth in correlation with the downregulation of GLUT1, cyclin D1 and ß-catenin. CONCLUSION: WNT2B plays a role in tumorigenesis and chemotherapy resistance in oral cancer and provide a potential therapeutic target for the treatment of patients with HNSCC.

Inhibition of glucose transporter 1 (GLUT1) chemosensitized head and neck cancer cells to cisplatin.

Glucose transporter 1 (GLUT1) facilitates the cellular uptake of glucose and is overexpressed in most cancers. The altered expression of GLUT1 may influence the sensitivity of tumor cells to chemotherapy. This study investigated whether the knockdown of GLUT1 expression to sensitize head and neck cancer cells to the chemotherapy drug cisplatin in vitro. Anti-GLUT1 antibody was used to block activity of GLUT1 protein, and GLUT1-shRNA was used to knock down its mRNA expression in Cal27 cells. Immunocytochemistry, Western blot, and qRT-PCR were used to detect expression of GLUT1 mRNA and protein, respectively. Lentivirus was used to carrying GLUT1-shRNA to knockdown GLUT1 expression in Cal27 cells for MTT and flow cytometry analyses of cell viability and apoptosis, respectively. Glucose uptake assay was used to assess the changes in glucose levels in Cal27 cells. It showed that GLUT1 mRNA and protein were expressed in Cal27 cells, and GLUT1 protein was localized on the cell membrane. Both anti-GLUT1 antibody and GLUT1-shRNA sensitized Cal27 cells to cisplatin treatment under both normoxia and hypoxia conditions. Anti- GLUT1 antibody and GLUT1-shRNA inhibited tumor cell growth in vitro and induced them to undergo apoptosis. GLUT1-shRNA also suppressed tumor cell uptake of glucose into the cells. Our findings suggest that inhibition of GLUT1 activity and expression can sensitize Cal27 cells to cisplatin treatment in both normoxic and hypoxic conditions. These data could be further verified in animal xenografts before potential application as a clinical adjuvant or neoadjuvant therapy of head and neck cancer with cisplatin.

Establishment and characterization of a rabbit oral squamous cell carcinoma cell line as a model for in vivo studies.

The incidence of oral squamous cell carcinoma (SCC) is increasing but the long-term survival rate remains low. An animal model would therefore be helpful for evaluation of new treatment modalities for oral SCC. Hamster is small animal, therefore, the cancer of hamster cheek pouch is not optimal for tumor imaging. The VX2 cell line has been used in many carcinoma-related studies, including oral SCC research, but it is derived from cutaneous tissue and not mucosa. We chemically induced tongue squamous cell carcinoma in rabbits and subsequently established a rabbit squamous cell line. The cells grew in multiple layers without contact inhibition for 60 passages over 2 years and were positive for cytokeratin (CK). Electron microscopy revealed that cells were polygonal with rich microvilli on the surface, and there were desmosomes between cells and bundles of tonofibril beside the cell membrane. The chromosome number ranged from 71 to 272, with a modal value of 145 (12.4%). The cells were transplantable into nude mice subcutaneously or rabbit submucosally and produced carcinomas in all the animals. The cell line should be a useful tool for the study of the biological characteristics of oral SCC, especially tongue SCC.

[Evaluation of fluorodeoxyglucose-position-emission tomography-computer tomography imaging on head and neck squamous cell carcinomas including primary tumors and lymph node metastases].

OBJECTIVE: To evaluate (18)F-fluorodeoxyglucose-position-emission tomography-computer tomography imaging ((18)F-FDG-PET-CT) on head and neck squamous cell carcinoma(HNSCCA) and lymph node metastasis. METHODS: (18)F-FDG-PET-CT imaging of 20 patients with HNSCCA was evaluated retrospectively. RESULTS: All the primary tumors were correctly diagnosed by (18)F-PET-CT imaging and SUV(avg) of the primary tumors was (6.22 +/- 2.20). All the sensitivity, specificity, positive predictive value and the negative predictive value were 100%. In detecting lymph node metastasis, the sensitivity was 51%, specificity 97.7%, false positive rate 2.3%, false negative rate 49%, positive predictive value 82%, and negative predictive value 91.2%. CONCLUSIONS: (18)F-FDG-PET-CT imaging was valuable in detecting HNSCCA and lymph node metastasis. SUV was helpful for differential diagnosis between benign or malignant tumors but it needs further study to determine the cutoff SUV for differentiating lymph node metastasis.

Expression of Glut-1 in primary and recurrent head and neck squamous cell carcinomas, and compared with 2-[18F]fluoro-2-deoxy-D-glucose accumulation in positron emission tomography.

The aim of the study was to investigate the pattern of glucose transporter-1 (Glut-1) expression in primary and recurrent head and neck squamous cell carcinomas (HNSCCAs) and the relation between Glut-1 expression and 2-[18F]fluoro-2-deoxy-D-glucose - positron emission tomography (FDG-PET). Standardised uptake values (SUVs) were used to evaluate FDG uptake by the tumour. Sections were stained immunohistochemically for Glut-1, which showed that high SUVs were seen in all HNSCCAs, and patients with higher T stage tumours or less well-differentiated tumours showed significantly higher SUVs than those with lower stage tumours or better-differentiated tumours (P=0.001 and 0.04, respectively). Glut-1 immunostaining was present in all cases. The Glut-1 staining index in primary HNSCCAs was significantly lower than that in recurrent HNSCCAs (P=0.03), and the index of better-differentiated tumours lower than that of poorly-differentiated tumours (P=0.02). However, there was no significant correlation between SUV(mean) and the Glut-1 staining index. In conclusion, our data suggest that high FDG uptakes were seen with overexpression of Glut-1 in primary and recurrent HNSCCAs. SUV(mean) was related to tumour T stage and grade of differentiation, which indicated that SUV was helpful in evaluating tumours. The expression of Glut-1 in recurrent HNSCCAs was higher than that in primary HNSCCAs, and in poorly-differentiated HNSCCAs higher than in better-differentiated HNSCCAs, which indicated that Glut-1 may have a useful role as a predictor for poor prognosis in HNSCCAs. However, there was no significant correlation between FDG accumulation and Glut-1 expression.

[Genetic linkage analysis and mutation detection in Chinese families with basal cell nevus syndrome].

OBJECTIVE: To study the molecular genetic etiology of a Chinese pedigree with basal cell nevus syndrome. METHODS: The proband and his affected mother and a unaffected individual in the pedigree were chosen and peripheral blood was collected from them for DNA. Direct sequencing was performed to detect the mutations of PTCH gene. In order to further confirm the results of sequence analysis, all available family members were analyzed with genetic linkage analysis using 3 highly polymorphic microsatellite DNA markers in the region of 9q22.3-q31. RESULTS: No mutations of PTCH gene was detected in the proband's mother, one synonymous mutation was detected in the proband. Linkage analysis showed that the Lod scores of the 3 markers were: D9S283, Z = -2.11 (theta = 0.00); D9S1690, Z = -2.95 (theta = 0.00); D9S1677, Z = -5.94 (theta = 0.00). CONCLUSIONS: In this pedigree, mutation of PTCH gene is not related to the underlying pathogenesis of the syndrome.

[A study on the mechanism of inducing apoptosis of Tca8113 cells by means of ultrasound hyperthermia].

PURPOSE: To investigate the mechanism of apoptosis in Tca8113 cells induced by ultrasound hyperthermia by detecting changes in related index. METHODS: Tca8113 cells were treated in vitro by ultrasound hyperthermia in different heating temperatures (38 degrees C to 44 degrees C,10 minutes) and heating times (42 degrees C,10 to 60 minutes), and then the dynamic changes of early apoptosis and secondary necrosis treated by 42 degrees C for 10 minutes were assayed to detect deltapsim and Caspase-3 levels of different groups by flow cytometry (FCM). The means of each group were compared by ANOVA with SAS6.12 software package. RESULTS: After heated by ultrasound in 42 degrees C for 10 minutes, the early apoptosis of Tca8113 was detected. The apoptosis index reached its highest level at the 6th to 8th hour, then decreased rapidly and maintained in a lower level after 12 hours. The level of secondary necrosis increased with the level of early apoptosis, but kept in a higher level until the 10th hour, the level of secondary necrosis correlated with that of the early apoptosis (r = 0.7909, P = 0.0064). The fraction of cells with low mitochondria membrane potential and increased activity of Caspase-3 were detected either in the heating-temperature grads group or in the heating-time grads group, which showed significant relationship between thetwo apoptosis related index (r = 0.89189, P = 0.0029 in the heating-temperature grads group; r = 0.9679, P = 0.0003 in the heating-time grads group). CONCLUSIONS: Tca8113 cells developed apoptosis after heated by ultrasound hyperthermia along with deltapsim level decreasing and Caspase-3 activity increasing. Ultrasound hyperthermia induces apoptosis of Tca8113 cells by the mitochondrum-Caspase pathway.

[Induction of mouse embryonic stem cells forming odontoblast-like cells by co-culture with pulp fibroblast].

PURPOSE: To investigate the methods of induction of mouse embryonic stem cells to differentiate into odontoblast-like cells by co-culture with pulp fibroblast. METHODS: By suspension culture, embryonic stem cells were induced to form embryoid bodies. Then the cells from embryoid bodies were co-cultured with pulp fibroblast in Transwell system for differentiation toward odontoblast-like cells. RESULTS: By RT-PCR analysis, embryoid body cells gave rise to the cell population expressing DSPP, a specific odontoblast cell marker, after 10 days of co-culture with pulp fibroblast and the expression of DSPP was enhanced after 15 days of co-culture. On the other hand, the expression of DSPP was not detected in the isolately cultured embryoid body cells. CONCLUSIONS: Embryonic stem cells can be induced into odontoblast-like cells by co-culture with pulp fibroblast. Supported by Science and Technology Development Fund of Shanghai Municipality (Grant No. 03ZR14027).