Clinical Prediction Nomograms to Assess Overall Survival and Disease-Specific Survival of Patients with Salivary Gland Adenoid Cystic Carcinoma.

Aim: Salivary gland adenoid cystic carcinoma (SACC) is the second highest incidence of malignant salivary gland tumor. The purpose of this study was to establish nomograms combined with SACC patients based on the Surveillance, Epidemiology, and End Results (SEER) database. Methods: Patients with SACC were included in the SEER∗Stat Database from 2004 to 2016. The least absolute shrinkage and selection operator (LASSO) Cox regression analysis was applied to filter potential prognostic clinical variables. Multivariate analysis from the Cox proportional hazards model was performed to determine the independent prognostic factors on overall survival (OS) and disease-specific survival (DSS), applied to develop nomograms. The Schönfeld residual test verified the proportional hazard assumption. The discrimination and consistency of nomograms was assessed and validated according to concordance index (C-index), receiver operating characteristic (ROC) curves, and calibration curves using an internal 1,000 times bootstrap resampling. The nomogram's net clinical benefit was assessed through decision curve analysis (DCA). Results: A total of 658 patients with SACC were included. Age, T stage, N stage, M stage, histologic grade, and surgery were independent prognostic factors for OS and DSS. Based on these independent prognostic factors, nomograms were developed to predict 3-, 5-, and 10-year OS and DSS. In the validation of 1,000 times bootstrap resampling, the C-index and ROC curves had good discriminatory ability. The calibration curves indicated excellent consistency between the predicted and actual survival results in the nomograms. The DCA curves demonstrated that the nomograms had good clinical benefit and were superior to the TNM stage and other variables. Conclusions: Two nomograms developed in this study precisely predicted the 3-, 5-, and 10-year OS and DSS rates of patients with SACC in accordance with independent prognostic factors, and their clinical value is better than TNM staging, providing a prognostic reference for other SACC patients.

New Pqs Quorum Sensing System Inhibitor as an Antibacterial Synergist against Multidrug-Resistant Pseudomonas aeruginosa.

Development of new bacterial biofilm inhibitors as antibacterial synergists is an effective strategy to solve the resistance of Pseudomonas aeruginosa. In this paper, a series of 3-hydroxy-pyridin-4(1H)-ones were synthesized and evaluated, and the hit compound (20p) was identified with the effects of inhibiting the production of pyocyanin (IC50 = 8.6 µM) and biofilm formation (IC50 = 4.5 µM). Mechanistic studies confirmed that 20p inhibits the formation of bacterial biofilm by inhibiting the expression of pqsA, blocking pqs quorum sensing system quinolone biosynthesis. Moreover, we systematically investigated the bactericidal effects of combining currently approved antibiotics for CF including tobramycin, ciprofloxacin, and colistin E with 20p, which showed obvious antibacterial synergy to overcome antibiotics resistance in multidrug-resistant P. aeruginosa biofilms. The result indicates that compound 20p may be used in the future as a potentially novel antibacterial synergist candidate for the treatment of P. aeruginosa infections.

Novel 2-Substituted 3-Hydroxy-1,6-dimethylpyridin-4(1H)-ones as Dual-Acting Biofilm Inhibitors of Pseudomonas aeruginosa.

2-Heptyl-3-hydroxy-4(1H)-quinolone (PQS), a compound from P. aeruginosa, functions as both a quorum sensing (QS) regulator and a potent iron chelator to induce expression of pyoverdine and pyochelin which are involved in high-affinity iron transport systems. A potential dual-acting antibiofilm strategy requires molecules designed to interfere with iron uptake and the QS system of P. aeruginosa. A series of 2-substituted 3-hydroxy-1,6-dimethylpyridin-4-ones have been designed, synthesized, and tested as biofilm inhibitors of P. aeruginosa. One compound, N-((1,3,6-trimethyl-4-oxo-1,4-dihydropyridin-2-yl)methyl)hexanamide (10d), exhibits 68.67% biofilm inhibitory activity at 20 µM. Further mechanistic studies have confirmed that this compound not only inhibits the QS systems of P. aeruginosa but also acts as an iron chelator to compete strongly with pyoverdine, causing iron deficiency in bacteria. The pyoverdine receptor FpvA was revealed as the target of 10d by the Pvds mutant strain, fpvA-overexpressed strain, and in silico studies.

Molecular Mechanisms of Chemoresistance in Oral Cancer.

Oral cancer is an aggressive disease with the propensity for local recurrence and distal metastasis in the head and neck region. Currently, cisplatin-based chemotherapy or concurrent radiochemotherapy is still the first choice to treat the advanced stage cancers, in particular, the unresectable tumours. Unfortunately, innate and acquired resistance to chemotherapy agent greatly limited its effectiveness and often led to treatment failure in these patients. Hence, it is urgent to clarify the mechanisms underlying the development of chemoresistance in patients with oral cancer. In this article, the current understandings on molecular mechanisms of chemoresistance in oral cancer were reviewed, including drug efflux, apoptosis, DNA damage and repair, epithelial mesenchymal transition, autophagy and miRNA.

Application of CAD/CAM-assisted technique with surgical treatment in reconstruction of the mandible.

OBJECTIVE: The purpose of this clinical study was to explore the optimal method of reconstruct mandible defects individually and immediately. STUDY DESIGN: Three-dimensional model simulation technique and vascularized fibular osteomyocutaneous flap were used to repair 15 cases of mandible defects, which were caused by ameloblastoma. A three-dimensional computed tomography (CT) images were converted to a virtual model using CAD software and the 3-dimensional (3D) simulated resin models of skeleton and fibula were used to design the osteotomies, bone segment replacement and titanium mesh shaping preoperatively. RESULTS: Fibula flaps were alive and no complication occurred. The patients were satisfied with the results both esthetically and functionally. CONCLUSIONS: This preliminarily clinical study and case demonstrated that CAD/CAM-assisted technique with surgical treatment offers an individual anatomical reconstruction of the mandible in ameloblastoma patients. The procedures guarantee intraoperatively an exact placement of the preformed mesh even for precise reconstruction of extensive mandible defects.

[Reconstruction of the tongue with rectus abdominis musculoperitoneal flap].

OBJECTIVE: To investigate the outcome of surgical reconstruction of the tongue after hemiglossectomy with reinnervated rectus abdominis musculoperitoneal flaps in the treatment of tongue cancer. METHODS: Five patients underwent immediate reconstruction of the tongue and oral floor defects with rectus abdominis musculoperitoneal flaps after resection of squamous cell carcinoma of tongue. The rectus abdominis musculoperitoneal flap consists of the rectus muscle, posterior rectus sheath, peritoneum, the 10 th, 11th, 12th intercostal nerves and the vascular pedicle that includes the deep inferior epigastric artery and veins. During the operation a reinnervated rectus abdominis musculoperitoneal free flap, in which the intercostal nerves were anastomosed to the descending branch of hypoglossal nerve, was grafted to remaining tongue stump. RESULTS: All patients recovered uneventfully from surgery, with no immediate postoperative complications. All transplanted flaps survived. The peritoneum was replaced by squamous epithelium 8 weeks after surgery. The average follow-up period was 10 months. During the follow-up period the contour of the reconstructed tongues was satisfactory. The patients demonstrated good functional mobility of the reconstructed and remaining tongue. The swallowing and speech function was nearly at normal levels and the patients could ingest a solid or semisolid diet. CONCLUSIONS: Reconstruction of the tongue with rectus abdominis musculoperitoneal flaps after hemiglossectomy is a suitable, cosmetically acceptable method. Long-term follow-up is needed for reaching some final conclusions.

[Study on the relationship between Fas expression and apoptosis in oral squamous cell carcinoma].

OBJECTIVE: To investigate the relationship of Fas mRNA and protein expression and apoptosis in human oral squamous cell carcinoma. METHODS: Northern blot and flow cytometry (TUNEL method) were used to detect the expression of Fas mRNA and Fas protein, cell cycle and apoptotic level in oral squamous cell carcinoma. The relationship between Fas gene expression and OSCC apoptosis was analyzed statistically. RESULTS: Fas mRNA and protein could be detected in all five normal oral mucosa specimens. There was positive correlation between expression of Fas mRNA/protein and cell differentiation as well as apoptosis in OSCC (P < 0.005). CONCLUSION: The expression of Fas gene was highly correlated with the differentiation and apoptosis in OSCC.

[The inhibitory effect of human endostatin gene on tumor growth of tongue squamous cell carcinoma].

OBJECTIVE: To investigate the expression of transfected human endostatin (hES) gene in tongue squamous cell carcinoma (TSCC) and its inhibitory effects on the growth of tumor cells in vivo. METHODS: Lipofectamine-mediated hES gene was transferred into Tca8113 cells, selected with Blasticidin S; The stable transfected cells were inoculated in BALB/c mice, and then the growth of xenografts was observed. The hES and vascular endothelial growth factor (VEGF) protein expression of xenografts was detected by S-P immuno-histochemical assay. We also detected the microvessel density (MVD) of xenografts with Weidern's method and apoptotic index of the tumor cells by flow cytometry (FCM). RESULTS: The hES protein expression of xenografts in experimental group was significantly higher than that in control group (P < 0.01), while the expression of VEGF protein was on the other way round (P < 0.01). MVD counting of xenografts in experimental group was lower than that in control group (P < 0.01). The mean apoptotic level of the tumor cells in control group was also lower than in experimental group (P < 0.01). In addition, the inhibitory rate to growth of xenografts induced by hES transfection was 78.9%. CONCLUSIONS: hES gene can be transferred into TSCC cells and then induce corresponding protein expression efficiently in xenograft model, resulting in significantly inhibitory effects on the xenografts in vivo.

[Effect of fas gene transfection on tumourigenicity and proliferation of transplanted tumor of oral squamous cell carcinoma cell line Tca8113].

OBJECTIVE: To investigate the effect of fas gene transfection and monoclonal anti-fas antibody on tumorigenicity and proliferation of transplanted tumor of Tca8113 cell. METHODS: Plasmid including fas gene was transfected into Tca8113 cell by lipofectamine kit. Some transfected cells were treated by monoclonal anti-fas antibody after 48 hours since transfection. Untransfected cell (control), fas-tansfected cell and fas-transfected cell treated with antibody were transplanted to nude mice subcutaneously. Growth of transplanted tumor was observed and recorded regularly. Animals were sacrificed and tumor samples were harvested at the end of experiment. Fas expression in each neoplasm was assessed by RT-PCR. Apoptosis, proliferation and expression of fas protein in tumor tissue were measured by flow cytometry (FCM). RESULTS: Tumor occurred much later in fas-transfected group and fas-transfected plus antibody treated group. Growth arrest was found in them. RT-PCR and FCM suggested that fas-transfection up-regulated the expression of fas mRNA and protein, increased apoptosis index (AI). But no effect on proliferation index (PI) was observed. Monoclonal anti-fas antibody did not effect the expression of fas mRNA and protein, but increased AI and decreased PI. CONCLUSION: Fas-transfection suppressing tumorigenesis of Tca8113 cell transplanted in nude mice might be caused by up-regulation of expression of fas gene and enhancement of apoptosis. However, anti-fas antibody suppressing tumorigenesis might be associated with activation of apoptosis and repression of proliferation.

[Transfection of human endostatin gene with lipofectamin and the expression of hES protein in Tca8113 cell].

OBJECTIVE: The purpose of this study was to establish transfergeneic Tca8113 cell and evaluate the expression of human endostatin (hES) gene in the cell colone in vitro. METHODS: To transfect hES gene into Tca8113 cells, lipofectamin was complexed with plasmid encoding hES gene, and blasticidin S antibiotic was adopted to select Tca8113--hES cell clone. Immunohistochemistry S-P method was adopted to detect the expression of hES in the transfergenic Tca8113 cell in vitro. RESULTS: Transfected by hES, the transfergenic Tca8113 cells could grow and proliferate in RPMI--1640 culture medium containing blasticidin S antibiotic. The expression rate of hES reached 100%. CONCLUSION: hES gene can express in hES-transfected Tca8113 cell in vitro.

[Maxilla reconstruction with the free iliac osteomuscular flap and simultaneous osseointegrated implant embeding].

OBJECTIVE: To evaluate the clinical outcome of reconstruction of maxillary defects with vascularized iliac crest flap and simultaneous osseointegrated implant embedding. METHODS: During September to October 2003, two patients with maxillary defects from tumor resection underwent microsurgical reconstruction. The free iliac osteomuscular flap transferring and simultaneous osseointegrated implant embedding were performed to repair the defects. Three months after the reconstructive surgery, an abutment operation was preformed and denture was applied in both cases. RESULTS: The flaps survived well. Postoperative follow-up for 8 to 9 months showed that the patients obtained good zygomaxillary appearance, normal occlusion, and satisfactory pronunciation, without oronasal fistula or other serious complications. CONCLUSIONS: The free iliac crest osteomuscular flap with simultaneous osseointegrated implant embedding is an ideal, effective and cosmetically acceptable method for maxilla reconstruction.

[Relationship of apoptosis and expression of Fas gene in tongue squamous cell carcinoma cell line Tca8113].

OBJECTIVE: To investigate the relationship of apoptosis and expression of Fas gene in oral squamous cell carcinoma. METHODS: Plasmid including Fas gene was transfected into Tca8113 cell by lipofectamine kit. The expression of Fas mRNA in transfected and non-transfected cell was detected by RT-PCR. The expression of Fas protein and apoptosis index(AI) was assessed by flow cytometry(FCM). RESULTS: No variation of positive expression rate of Fas protein was found in Fas-transfected and non-transfected Tca8113 (P > 0.05), but the expression of Fas mRNA, intensity of Fas protein and apoptosis index were significantly increased respectively from 0.201 +/- 0.015, 31.02 +/- 4.63, 0.88% +/- 0.16% to 0.399 +/- 0.073, 54.32 +/- 6.38 and 10.21% +/- 1.46%(P < 0.01). CONCLUSION: Apoptosis in tongue squamous cell carcinoma was not directly associated with the positive expression rate but intensity of Fas protein. A liminal value might exist before apoptosis in Tca8113 cell could be activated.

[Effect of c-myc transfection on fas expression and apoptosis in oral squamous cell carcinoma cell line Tca8113].

BACKGROUND AND OBJECTIVE: The process of carcinogenesis is not only correlated to the abnormality of cell proliferation but also to the change of normal cell apoptosis. The aim of this study was to investigate the mechanism of apoptosis induced by c-myc(cellular avian myelocytoma virus) gene in oral squamous cell carcinoma cell line Tca8113. METHODS: Plasmid including c-myc gene was transfected into Tca8113 cell by using lipofectamine kit. The cells were selected by G418. The expression of fas(fatty acid synthase) gene in transfected and non-transfected Tca8113 cell was detected by RT-PCR. Apoptosis of Tca8113 cell was determined by TUNEL. RESULTS: Up-regulation of fas expression was found in c-myc transfected Tca8113 cell. The increased apoptosis index (AI) could only be found under the condition of low serum concentration. CONCLUSIONS: c-myc could mediate apoptosis of oral squamous cell carcinoma in certain condition. This might be related with the up-regulation of fas expression.