STAT3 regulates SRGN and promotes metastasis of nasopharyngeal carcinoma through the FoxO1-miR-148a-5p-CREB1 axis.

Nasopharyngeal carcinoma (NPC), which is marked by a distinct distribution, is a common subtype of epithelial carcinoma arising from the nasopharyngeal mucosal lining. SRGN acts as an important and poor prognostic factor of NPC through multiple different mechanisms. However, the biological role and mechanism of SRGN in NPC remain unknown. Expression levels of miR-148a-5p, CREB1, FoxO1, and SRGN in NPC tissues and cell lines were tested by qRT-PCR or/and Western blot. The impacts of miR-148a-5p, CREB1, FoxO1, and SRGN on NPC cell viability, proliferation, migration, and invasion were estimated in vitro by CCK-8, colony formation, wound healing and Transwell experiments, and in vivo by a xenograft tumor model. JASPAR analysis was used to predict the binding activity of Foxo1 (CREB1) with the miR-148a-5p (SRGN) promoter, and the interaction was validated by EMSA and ChIP assays. The miR-148a-5p-CREB1 interaction was validated by a dual-luciferase reporter and RIP assays. CREB1 and SRGN were increased while miR-148a-5p was decreased in NPC. Silencing of SRGN and CREB1, as well as miR-148a-5p overexpression, repressed NPC tumor progression in vitro and in vivo. CREB1 promoted SRGN expression in NPC by targeting the promoter area of SRGN. Silencing of FoxO1 facilitated NPC tumor progression, while silencing of STAT3 repressed NPC tumor progression. FoxO1 bound to and regulated miR-148a-5p in NPC, and miR-148a-5p targeted CREB1. Additionally, FoxO1 knockdown abolished the downregulation of CREB1 and SRGN induced by STAT3 silencing. Our results suggest that STAT3 regulates SRGN and promotes the growth and metastasis of NPC through the FoxO1-miR-148a-5p-CREB1 axis.

A new hybrid fractal algorithm for predicting thermophilic nucleotide sequences.

Knowledge of thermophilic mechanisms about some organisms whose optimum growth temperature (OGT) ranges from 50 to 80 degree plays a major role in helping design stable proteins. How to predict a DNA sequence to be thermophilic is a long but not fairly resolved problem. Chaos game representation (CGR) can investigate the patterns hiding in DNA sequences, and can visually reveal previously unknown structure. Fractal dimensions are good tools to measure sizes of complex, highly irregular geometric objects. In this paper, we convert every DNA sequence into a high dimensional vector by CGR algorithm and fractal dimension, and then predict the DNA sequence thermostability by these fractal features and support vector machine (SVM). We have conducted experiments on three groups: 17-dimensional vector, 65-dimensional vector, and 257-dimensional vector. Each group is evaluated by the 10-fold cross-validation test. For the results, the group of 257-dimensional vector gets the best results: the average accuracy is 0.9456 and average MCC is 0.8878. The results are also compared with the previous work with single CGR features. The comparison shows the high effectiveness of the new hybrid fractal algorithm.

Prognostic value of hypothyroidism in patients undergoing intensity-modulated radiation therapy for nasopharyngeal carcinoma.

BACKGROUND: The purpose of this study was to investigate the effect of hypothyroidism and thyroxine replacement therapy on the prognosis of nasopharyngeal carcinoma (NPC) patients. METHODS: The clinical data of 284 NPC patients, who received intensity-modulated radiation therapy (IMRT) between January 2011 and December 2016, were retrospectively analyzed. RESULTS: Hypothyroidism occurred in 38% of patients. Patients with hypothyroidism had significantly better disease-free survival (DFS) (p = 0.002) and relapse-free survival (RFS) (p = 0.008). Multivariate analysis showed that hypothyroidism was a positive independent prognostic factor (DFS and RFS). Among the patients with hypothyroidism, thyroxine replacement therapy did not yield inferior survival (DFS, RFS, all p > 0.05). CONCLUSIONS: The NPC patients with complete response are at risk of hypothyroidism, which is attributable to escalating dose. These patients experienced clinical hypothyroidism could be adequately treated with thyroid hormone replacement. Further investigation of the underlying biological mechanism and potential therapeutic implications are required.

Effects of hepatitis B virus infection and antiviral therapy on the clinical prognosis of nasopharyngeal carcinoma.

PURPOSE: To investigate the clinical characteristics of nasopharyngeal carcinoma (NPC) and a concomitant hepatitis B virus (HBV) infection, as well as the potential effects of HBV infection and antiviral therapy on prognosis. METHODS: We conducted a retrospective chart review of all NPC patients from December 2010 to December 2014. After collecting medical records and conducting follow-ups on patients, a total of 876 eligible NPC patients were included. For each patient, medical records were reviewed. Factors predictive of outcome were compared using the log-rank test and Cox regression analysis. RESULTS: Among the 876 participants, 106 (12.1%) patients were HBV-infected patients. The hepatitis B surface antigen-positive [HBsAg(+)] group had a lower CD4+ T cell count than the HBsAg(-) group (P = .048). Among patients with stage I/II NPC, 5-year overall survival (OS), disease-free survival (DFS), relapse-free survival, and distant metastasis-free survival (DMFS) of the HBsAg(+) group were 82.5%, 70.7%, 87.7%, and 76.6%, respectively, whereas those of the HBsAg(-) group were 91.4%, 86.0%, 93.8%, and 92.1%, respectively. Statistically significant differences in OS, DFS, and DMFS existed between both groups (P = .017, .018, and .004, respectively). The multivariate analysis indicated that HBsAg status and N stage are independent risk factors affecting OS, DFS, and DMFS of NPC patients. A statistically significant difference in 5-year DMFS existed between the antivirus (90.0%) and no-antivirus groups (70.0%) (P = .043). CONCLUSIONS: Hepatitis B virus infection is an independent risk factor for early stage NPC, which may be associated with its reduced immune functions compared to the HBsAg(-) group. Anti-HBV treatment may improve the prognosis of HBV-infected NPC patients.

Effects of Surgery Combined with Chemoradiotherapy on Short- and Long-Term Outcomes of Early-Stage Nasopharyngeal Carcinoma.

OBJECTIVE: The efficacy of surgery as the primary treatment modality for nasopharyngeal carcinoma (NPC) is yet to be clarified. Therefore, we aimed to explore the short- and long-term efficacy of surgery for early-stage NPC. METHODS: We retrospectively evaluated 341 patients diagnosed with early-stage NPC between September 2010 and December 2015. Among them, 58 patients underwent endoscopic nasopharyngectomy combined with chemoradiotherapy, whereas 283 patients underwent conventional chemoradiotherapy. The patients who underwent concurrent chemoradiotherapy or radiotherapy alone were matched to patients who underwent surgery in a 1:2 ratio using propensity score matching to analyze the clinical efficacy of each therapeutic modality. The primary endpoint was survival, and the secondary endpoints were tumor regression rate and reduction in Epstein-Barr virus (EBV)-DNA levels. RESULTS: After matching, 156 patients were enrolled (58 patients in the surgery group; 98 patients in the non-surgery group). The baseline data of the matched patients had good inter-group comparability (All P>0.05). The surgery group had significantly higher 5-year overall survival (98.30% vs. 91.70%), disease-free survival (98.30% vs. 81.40%), and recurrence-free survival (100.00% vs. 90.10%) rates than did the non-surgery group (All P<0.05). In total, 0 and 14 patients in the surgery and non-surgery groups, respectively, had residual cancer at the end of treatment (P=0.001). All patients in the surgery group tested negative for EBV-DNA, whereas two patients in the non-surgery group tested positive. The incidence of hematologic toxicity during treatment was similar between the two groups (All P>0.05). Still, the incidence of severe oral mucositis was lower in the surgery group than in the non-surgery group (37.9% vs. 54.08%, P=0.051). CONCLUSION: Surgery can improve the clearance rate of EB virus and reduce tumor residue. Surgery may be a safe and effective treatment for early NPC.

Predicting thermophilic proteins with pseudo amino acid composition:approached from chaos game representation and principal component analysis.

Comprehensive knowledge of thermophilic mechanisms about some organisms whose optimum growth temperature (OGT) ranges from 50 to 80 °C degree plays a major role for helping to design stable proteins. How to predict function-unknown proteins to be thermophilic is a long but not fairly resolved problem. Chaos game representation (CGR) can investigate hidden patterns in protein sequences, and also can visually reveal their previously unknown structures. In this paper, using the general form of pseudo amino acid composition to represent protein samples, we proposed a novel method for presenting protein sequence to a CGR picture using CGR algorithm. A 24-dimensional vector extracted from these CGR segments and the first two PCA features are used to classify thermophilic and mesophilic proteins by Support Vector Machine (SVM). Our method is evaluated by the jackknife test. For the 24-dimensional vector, the accuracy is 0.8792 and Matthews Correlation Coefficient (MCC) is 0.7587. The 26-dimensional vector by hybridizing with PCA components performs highly satisfaction, in which the accuracy achieves 0.9944 and MCC achieves 0.9888. The results show the effectiveness of the new hybrid method.

[Choice of surgical approaches for salvage surgery of primary lesion recurrence and residual cases of nasopharyngeal carcinoma].

OBJECTIVE: The choice of surgical approaches for salvage surgery based on the location and invasion of recurrent and residual lesions of nasopharyngeal carcinoma (NPC), surgical results, complications, and survival were assessed. METHODS: Thirty-seven cases with recurrent and residual lesions of NPC underwent salvage surgery between March 1991 and January 2005 were analysed retrospectively. Of 37 patients, 23 were men and 14 women, with a median age of 46.5 years (26 - 57 years); 4 were at stage I, 10 at stage II, 14 at stage III, and 9 at stage IV; 5 cases were with cervical metastasis, including 3 cases of N1 and 2 cases N2. All recurrent and residual lesions of NPC were determined by biopsy. On the location and invasion of recurrent and residual lesions of NPC, 8 cases underwent endoscopic resection of lesions, 12 cases of the palate nasopharyngectomy, 5 cases of maxillary swing, 4 cases of maxillary swing plus prerenal approach, 2 cases of lateral rhinotomy plus coronal flap approach, and 6 cases transfacial plus nasal pyramid swing approach. Five cases with cervical metastasis received neck dissection in addition to the operations for recurrent and residual lesions of NPC. Postoperatively 31 cases received radiotherapy with dosage of 60 Gy, among them 15 cases with concurrent chemoradiation therapy, and 6 cases with clear surgical margin did not received radiotherapy or chemotherapy. The cases were followed up for 12 - 72 months, with a median of 45 months. RESULTS: Total resection for the recurrent and residual lesions of NPC accounted for 91.8% (34/37) and subtotal resection for 8.2% (3/37). The accident of perioperative complications was 24.3% (9/37). The 3- and 5-year overall disease-free survival rates (DFSR) were 62.1% and 43.3%, respectively. The 3- and 5-year overall survival rates (OSR) were 72.9% and 51.3%, respectively. The 5 year DFSR of cases at stage I-IV were 100%, 40%, 28% and 11% (χ(2) = 10.0, P < 0.01), respectively. The 5 year OSR were 100%, 70%, 35% and 28% (χ(2) = 11.5, P < 0.01), respectively. CONCLUSIONS: Salvage surgery is a justified treatment for the recurrent and residual lesions of NPC, by which some patients with recurrent and residual lesions of NPC can be salvaged.