Pepsin-mediated inflammation in laryngopharyngeal reflux via the ROS/NLRP3/IL-1ß signaling pathway.

BACKGROUND: Laryngopharyngeal reflux (LPR) is one of the most common disorders in otorhinolaryngology, affecting up to 10% of outpatients visiting otolaryngology departments. In addition, 50% of hoarseness cases are related to LPR. Pepsin reflux-induced aseptic inflammation is a major trigger of LPR; however, the underlying mechanisms are unclear. The nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome has become an important bridge between stimulation and sterile inflammation and is activated by intracellular reactive oxygen species (ROS) in response to danger signals, leading to an inflammatory cascade. In this study, we aimed to determine whether pepsin causes LPR-associated inflammatory injury via mediating inflammasome activation and explore the potential mechanism. METHODS: We evaluated NLRP3 inflammasome expression and ROS in the laryngeal mucosa using immunofluorescence and immunohistochemistry. Laryngeal epithelial cells were exposed to pepsin and analyzed using flow cytometry, western blotting, and real-time quantitative PCR to determine ROS, NLRP3, and pro-inflammatorycytokine levels. RESULTS: Pepsin expression was positively correlated with ROS as well as caspase-1 and IL-1ß levels in laryngeal tissues. Intracellular ROS levels were elevated by increased pepsin concentrations, which were attenuated by apocynin (APO)-a ROS inhibitor-in vitro. Furthermore, pepsin significantly induced the mRNA and protein expression of thioredoxin-interacting protein, NLRP3, caspase-1, and IL-1ß in a dose-dependent manner. APO and the NLRP3 inhibitor, MCC950, inhibited NLRP3 inflammasome formation and suppressed laryngeal epithelial cell damage. CONCLUSION: Our findings verified that pepsin could regulate the NLRP3/IL-1ß signaling pathway through ROS activation and further induce inflammatory injury in LPR. Targeting the ROS/NLRP3 inflammasome signaling pathway may help treat patients with LPR disease.

Development and validation of a nomogram to predict cancer-specific survival in patients with hypopharyngeal squamous cell carcinoma treated with primary surgery.

OBJECTIVE: We aimed to develop a nomogram to predict cancer-specific survival (CSS) in patients with hypopharyngeal squamous cell carcinoma (HSCC) treated with primary surgery to provide more accurate risk stratification for patients. METHODS: We retrospectively collected data of 1144 eligible patients with HSCC from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. Patients were randomly divided into training and validation groups (ratio 6:4) and we used univariate and multivariate Cox analysis. We developed and validated a nomogram using calibration plots and time-dependent receiver operating characteristic, Kaplan-Meier, and decision curves. RESULTS: Age; marital status; T, N, and M stage; and postoperative adjuvant therapy were independent factors associated with CSS, which were included in the nomogram. The nomogram's C-index was 0.705 to 0.723 in the training group and 0.681 to 0.736 in the validation group, which were significantly higher than conventional American Joint Committee on Cancer (AJCC) staging. Calibration curves showed good agreement between prediction and observation in both groups. Kaplan-Meier and decision curves suggested the nomogram had better risk stratification and net benefit than conventional AJCC staging. CONCLUSIONS: We established a nomogram that was superior to conventional AJCC staging in predicting CSS for HSCC.

Survival benefit of induction chemotherapy for locally advanced nasopharyngeal carcinoma: prognosis based on a new risk estimation model.

BACKGROUND: Although the National Comprehensive Cancer Network (NCCN) Guidelines recommend CCRT+AC and IC + CCRT as level 2A evidence for treatment of the locoregionally advanced NPC (II-IVa), IC + CCRT+AC could also be an alternative but it is seldom used because of the low completion rates. This article aimed to compare the effectiveness of the three radiotherapy regimens using a large-scale retrospective study. METHODS: This retrospective single center analysis enrolled 1812 diagnosed NPC patients at Nanfang Hospital from January 2005 to December 2015 and only 729 patients met the inclusion criteria and were analyzed. Patients without distant metastasis, age of 18-70 years, Karnofsky scores of at least 70,stage III-IVb, and adequate adequate bone marrow, liver and renal function. Were enrolled. Adverse events and other categorical variables were compared by Pearson chi-square test or Fishier exact test. Time-to-event data were described with the Kaplan-Meier curves, time-to-event intervals compared with the log-rank test. We did multivariable analyses with the Cox proportional hazards model to test the independent signifi cance of diff erent factors. Cox proportional hazards model was used to estimate the ß regression coeffi cient, p value, and hazard ratio and its 95% CI for each of the selected risk predictors. RESULTS: The median follow-up time was 47 months. Kaplan-Meier analyses revealed no significant differences among three groups in 3-year failure-free survival (FFS, P = 0.225), 3-year overall survival (OS, P = 0.992), 3-year locoregional failure-free survival (LFFS, P = 0.549), and 3-year distant failure-free survival (DFFS, P = 0.174). Stratified survival analysis based on the risk scoring model revealed no differences in FFS, OS, LFFS, and DFFS between IC + CCRT and CCRT+AC groups for low-risk patients, however, the 3-year OS (88.3% vs. 77.6%, P = 0.049) and 3-year DFFS (84.0% vs.66.8%, P = 0.032) were respectively significantly better in IC + CCRT group compared with CCRT+AC group for high-risk patients. CONCLUSIONS: Compared with CCRT+AC, IC + CCRT lowers distant metastasis rate and improves OS among patients with locally advanced NPC in high risk group.

Integrating pre- and post-treatment Plasma Epstein-Barr Virus DNA levels for better prognostic prediction of Nasopharyngeal Carcinoma.

Background: Pre- and post-treatment plasma Epstein-Barr virus (EBV) DNA are important biomarkers for the prognosis of nasopharyngeal carcinoma (NPC). This study was performed to determine the prognostic potential of integrating EBV DNA levels in plasma measured pre-treatment (pre-EBV) and 3 months post-treatment (3 m-EBV). Materials and methods: A total of 543 incident non-metastatic NPC patients treated with intensity-modulated radiotherapy, with or without chemotherapy, were reviewed. Patients were divided into four subgroups based on pre-EBV and 3 m-EBV status. The data for pre-EBV and 3 m-EBV samples were integrated, and the predictability of the survival of patients with NPC was analyzed. Results: There were significant differences in the 5-year progression-free survival, distant metastasis-free survival, locoregional relapse-free survival, and overall survival among the four patient subgroups (P<0.001). Patients who tested negative for both pre-EBV and 3 m-EBV had the best prognosis, followed by patients who tested positive for pre-EBV and negative for 3 m-EBV, and those who tested negative for pre-EBV and positive for 3 m-EBV; however, patients who tested positive for both pre-EBV and 3 m-EBV had the poorest chances of survival. Multivariate analyses demonstrated that integration of pre-EBV and 3 m-EBV data was an independent predictor of NPC progression in patients. Receiver operating characteristic curve analysis further confirmed that the combination of pre-EBV and 3 m-EBV had a greater prognostic value than pre-EBV or 3 m-EBV alone. Conclusions: Integrating pre-EBV and 3 m-EBV data could provide more accurate risk stratification and better prognostic prediction in NPC.

Association of pepsin and DNA damage in laryngopharyngeal reflux-related vocal fold polyps.

PURPOSE: This study aimed to evaluate if laryngopharyngeal reflux (LPR) plays a role as a risk factor for vocal fold polyps (VFPs), and if pepsin is associated with higher oxidative DNA damage of VFPs in the presence of LPR. METHODS: Thirty patients with VFPs were recruited between 2017 and 2018. Prior to surgery, a laryngoscopy was performed on all subjects to evaluate VFPs. Polyp tissue and saliva samples were obtained scrupulously. Hematoxylin-eosin staining was performed for pathologic analysis. Immunohistochemistry and ELISA were used to detect pepsin in tissue and saliva of VFP patients. 8-OHdG and p-H2AX expression was detected to measure oxidative DNA damage in tissue. DNA damage was investigated in human immortalized laryngeal epithelial cells exposed to pepsin. RESULTS: The pepsin concentration in saliva was significantly higher (t = 2.38, P = .024) in the pepsin positive group. There was no significant difference in pepsin expression at different sites and pathological subtypes of VFPs. The levels of 8-OHdG and p-H2AX were significantly higher in the pepsin positive group and positively correlated with the tissue expression of pepsin. The concentration of pepsin in saliva also showed a significant correlation with 8-OHdG levels. Expression of 8-OHdG and p-H2AX, and tail moment of the comet assay were elevated in human immortalized laryngeal epithelial cells following treatment with pepsin. CONCLUSION: Patients with VFPs have higher levels of oxidative DNA damage in the presence of pepsin reflux. Pepsin may induce DNA damage in laryngeal epithelial cells and participate in the pathogenesis of VFPs.