Bile reflux and hypopharyngeal cancer (Review)

Swertiamarin relieves radiation-induced intestinal injury by limiting DNA damage

Radiotherapy is the conventional treatment for pelvic abdominal tumors. However, it can cause some damage to the small intestine and colorectal, which are very sensitive to radiation. Radiation-induced intestinal injury (RIII) affects the prognosis of radiotherapy, causing sequelae of loss of function and long-term damage to patients' quality of life. Swertiamarin is a glycoside that has been reported to prevent a variety of diseases including but not limited to diabetes, hypertension, atherosclerosis, arthritis, malaria, and abdominal ulcers. However, its therapeutic effect and mechanism of action on RIII have not been established. We investigated whether swertiamarin has a protective effect against RIII. In this article, we use irradiator to create cellular and mouse models of radiation damage. Preventive administration of swertiamarin could reduce ROS and superoxide anion levels to mitigate the cellular damage caused by radiation. Swertiamarin also attenuated RIII in mice, as evidenced by longer survival, less weight loss and more complete intestinal barrier. We also found an increase in the relative abundance of primary bile acids in irradiated mice, which was reduced by both FXR agonists and swertiamarin, and a reduction in downstream interferon and inflammatory factors via the cGAS-STING pathway to reduce radiation-induced damage.

Potential Chemopreventive Role of Proton Pump Inhibitors in Head and Neck Cancer: Insights from a Nested Case-Control Analysis of a National Health Screening Cohort

Background/Objectives: This study investigated the potential chemopreventive role of proton pump inhibitor (PPI) use in relation to the occurrence of head and neck cancer (HNC) within a national cohort amid concerns of PPI overprescription. Methods: From a cohort of 1,137,861 individuals and 219,673,817 medical claim records collected between 2005 and 2019, 1677 HNC patients were identified and matched 1:4 with 6708 controls after adjusting for covariates. Odds ratios (ORs) for PPI use and its duration in relation to HNC and its subsites were estimated using propensity score overlap-weighted multivariable logistic regression. Additional subgroup analyses were performed based on age, sex, income level, and geographic region. Results: In the crude model, both current (OR 7.85 [95% CI 6.52-9.44]) and past PPI (OR 1.44 [95% CI 1.23-1.70]) use were associated with increased odds for HNC. However, after overlap weighting, this association reversed for both current (aOR 0.14 [95% CI 0.11-0.17]) and past PPI (aOR 0.69 [95% CI 0.60-0.79]). Subsite analysis showed reduced odds for hypopharyngeal (aOR 0.33, [95% CI 0.25-0.43]) and laryngeal cancer (aOR 0.19 [95% CI 0.16-0.22]) in current PPI users and similar results for past users. Conclusions: This study suggests a potential chemopreventive effect of PPIs, particularly in hypopharyngeal and laryngeal cancers. Additional studies are required to investigate the mechanisms underlying the association of the development of HNC with PPI use.

Novel non-invasive molecular signatures for oral cavity cancer, by whole transcriptome and small non-coding RNA sequencing analyses: Predicted association with PI3K/AKT/mTOR pathway

INTRODUCTION

Identification of molecular biomarkers in the saliva and serum of oral cavity cancer patients represents a first step in the development of essential and efficient clinical tools for early detection and post-treatment monitoring. We hypothesized that molecular analyses of paired saliva and serum samples from an individual would likely yield better results than analyses of either serum or saliva alone.

MATERIALS AND METHODS

We performed whole-transcriptome and small non-coding RNA sequencing analyses on 32 samples of saliva and serum collected from the same patients with oral squamous cell carcinoma (OSCC) and healthy controls (HC).

RESULTS

We identified 12 novel saliva and serum miRNAs and a panel of unique miRNA and mRNA signatures, significantly differentially expressed in OSCC patients relative to HC (log2 fold change: 2.6-26.8; DE: 0.02-0.000001). We utilized a combined panel of the 10 top-deregulated miRNAs and mRNAs and evaluated their putative diagnostic potential (>87% sensitivity; 100% specificity), recommending seven of them for further validation. We also identified unique saliva and serum miRNAs associated with OSCC and smoking history (OSCC smokers vs. never-smokers or HC: log2 fold change: 22-23; DE: 0.00003-0.000000001). Functional and pathway analyses indicated interactions between the discovered OSCC-related non-invasive miRNAs and mRNAs and their targets, through PI3K/AKT/mTOR signaling.

CONCLUSION

Our data support our hypothesis that using paired saliva and serum from the same individuals and deep sequencing analyses can provide unique combined mRNA and miRNA signatures associated with canonical pathways that may have a diagnostic advantage relative to saliva or serum alone and may be useful for clinical testing. We believe this data will contribute to effective preventive care by post-treatment monitoring of patients, as well as suggesting potential targets for therapeutic approaches.

The Dubai Definition and Diagnostic Criteria of Laryngopharyngeal Reflux: The IFOS Consensus

OBJECTIVE

The objective of this work was to gather an international consensus group to propose a global definition and diagnostic approach of laryngopharyngeal reflux (LPR) to guide primary care and specialist physicians in the management of LPR.

METHODS

Forty-eight international experts (otolaryngologists, gastroenterologists, surgeons, and physiologists) were included in a modified Delphi process to revise 48 statements about definition, clinical presentation, and diagnostic approaches to LPR. Three voting rounds determined a consensus statement to be acceptable when 80% of experts agreed with a rating of at least 8/10. Votes were anonymous and the analyses of voting rounds were performed by an independent statistician.

RESULTS

After the third round, 79.2% of statements (N = 38/48) were approved. LPR was defined as a disease of the upper aerodigestive tract resulting from the direct and/or indirect effects of gastroduodenal content reflux, inducing morphological and/or neurological changes in the upper aerodigestive tract. LPR is associated with recognized non-specific laryngeal and extra-laryngeal symptoms and signs that can be evaluated with validated patient-reported outcome questionnaires and clinical instruments. The hypopharyngeal-esophageal multichannel intraluminal impedance-pH testing can suggest the diagnosis of LPR when there is >1 acid, weakly acid or nonacid hypopharyngeal reflux event in 24 h.

CONCLUSION

A global consensus definition for LPR is presented to improve detection and diagnosis of the disease for otolaryngologists, pulmonologists, gastroenterologists, surgeons, and primary care practitioners. The approved statements are offered to improve collaborative research by adopting common and validated diagnostic approaches to LPR.

LEVEL OF EVIDENCE

5 Laryngoscope, 134:1614-1624, 2024.

Review article: Diagnosis and management of laryngopharyngeal reflux

BACKGROUND

Laryngopharyngeal reflux has classically referred to gastroesophageal reflux leading to chronic laryngeal symptoms such as throat clearing, dysphonia, cough, globus sensation, sore throat or mucus in the throat. Current lack of clear diagnostic criteria significantly impairs practitioners' ability to identify and manage laryngopharyngeal reflux.

AIMS

To discuss current evidence-based diagnostic and management strategies in patients with laryngopharyngeal reflux.

METHODS

We selected studies primarily based on current guidelines for gastroesophageal reflux disease and laryngopharyngeal reflux, and through PubMed searches.

RESULTS

We assess the current diagnostic modalities that can be used to determine if laryngopharyngeal reflux is the cause of a patient's laryngeal symptoms, as well as review some of the common treatments that have been used for these patients. In addition, we note that the lack of a clear diagnostic gold-standard, as well as specific diagnostic criteria, significantly limit clinicians' ability to determine adequate therapies for these patients. Finally, we identify areas of future research that are needed to better manage these patients.

CONCLUSIONS

Patients with chronic laryngeal symptoms are complex due to the heterogenous nature of symptom pathology, inconsistent definitions and variable response to therapies. Further outcomes data are critically needed to help elucidate ideal diagnostic workup and therapeutic management for these challenging patients.

A Novel Saliva and Serum miRNA Panel as a Potential Useful Index for Oral Cancer and the Association of miR-21 with Smoking History: a Pilot Study

Tobacco use is implicated in the carcinogenesis of oral squamous cell carcinoma (OSCC), which is associated with poor survival if not diagnosed early. Identification of novel noninvasive, highly sensitive, and cost-effective diagnostic and risk assessment methods for OSCC would improve early detection. Here, we report a pilot study assessing salivary and serum miRNAs associated with OSCC and stratified by smoking status. Saliva and paired serum samples were collected from 23 patients with OSCC and 21 healthy volunteers, with an equal number of smokers and nonsmokers in each group. Twenty head and neck cancer-related miRNAs were quantified by qPCR (dual-labeled LNA probes) and analyzed by Welch t test (95% confidence interval). Four saliva miRNAs, miR-21, miR-136, miR-3928, and miR-29B, showed statistically significant overexpression in OSCC versus healthy controls (P < 0.05). miR-21 was statistically significantly overexpressed in OSCC smokers versus nonsmokers (P = 0.006). Salivary miR-21, miR-136, and miR-3928, and serum miR-21 and miR-136, showed statistically significant differential expression in early-stage tumors versus controls (P < 0.05), particularly miR-21 in smokers (P < 0.005). This pilot study provides a novel panel of saliva and serum miRNAs associated with oral cancer. Further validation as a potential useful index of oral cancer, particularly miR-21 in smokers and early-stage OSCC is warranted.

PREVENTION RELEVANCE

Saliva and serum miR-21, miR-136, miR-3928, and miR-29B, are potentially associated with oral cancer even at an early stage, especially miR-21 in individuals with a smoking history, a further validation in a larger cohort of subjects with premalignant and early malignant lesions need to confirm.

Assessment of the risk factors of duodenogastric reflux in relation to different dietary habits in a Chinese population of the Zhangjiakou area

Objective

To explore the risk factors of duodenogastric reflux (DGR) in relation to different dietary habits.

Methods

A total of 106 patients with symptoms of DGR who underwent electronic gastroscopy from June 2019 to June 2020 were selected and divided into the DGR group (n = 33) and the non-DGR group (n = 73) according to the diagnosis of bile reflux. Questionnaires were used to collect the basic information and dietary habits of the patients, including age, gender, body mass index, place of residence, comorbidities, dietary composition, salt intake, smoking and drinking consumption. The total bile acid (TBA) and cholesterol (CHO) of the gastric juice were measured using a fully automated biochemical analyser, with an enzyme-linked immunosorbent assay used for the serum cholecystokinin, gastrin and gastrin levels. Univariate analysis and multivariate logistic regression analysis were used to predict the attendant DGR risk factors.

Results

There was no significant difference in age or gender between the DGR and the non-DGR groups (P > 0.05). The proportion of patients living in the Bashang region was significantly higher in the DGR group (78.79%) than in the non-DGR group (38.36%) (P < 0.05). The levels of TBA and CHO in the gastric juice and the cholecystokinin and gastrin levels in the serum of the DGR group were higher than those in the non-DGR group, while the serum motilin levels were significantly lower in the DGR group than in the non-DGR group (P < 0.05). The univariate analysis indicated that the proportion of patients with daily consumption of dairy products and fried foods, a high salt intake and smoking and drinking consumption were significantly higher in the DGR than in the non-DGR group (P < 0.05).

Conclusion

The daily consumption of dairy products and a preference for fried food are independent risk factors for the occurrence of DGR (odds ratio ≥ 1, P < 0.05).

[Characteristics performance of laryngopharyngeal reflux in narrow band imaging]

Objective:To study the application value of narrow-band imaging in the diagnosis of laryngopharyngeal reflux. Methods:A total of 275 patients admitted to the inpatient department or laryngoscopy room of the Otolaryngology Head and Neck Surgery Department of the First Affiliated Hospital of Harbin Medical University from September 2022 to April 2023 due to throat discomfort were selected as the research subjects. All of them completed RSI, RFS scoring scales and electronic laryngoscopy（including ordinary white light and NBI）. According to the expert consensus of LPRD in 2022, RSI and RFS scoring scale were used as diagnostic criteria to divide them into LPR group and non-LPR group. Chi-square test was used to analyze the differences of positive rates of characteristic manifestations under NBI among different groups. The consistency of NBI and scale diagnostic methods was analyzed by Kappa, and RSI and RFS scoring were used as diagnostic criteria, The diagnostic efficiency of NBI method was analyzed. Results:There were 190 people in the LPR group, 157 of whom showed characteristic performance under the NBI mode, with a positive rate of 82.6%（157/190）; there were 85 people in the non-LPR group, with a positive rate of 18.8%（16/85）. There was a statistically significant difference in the positive rate between the two groups（χ²=102.47, P<0.05）. The consistency rate between RSI, RFS and NBI was 82.2%（226/275）. Kappa consistency analysis was used, and Kappa=0.605（P<0.05）, indicating good consistency between the two diagnostic methods. Using RSI and RFS as diagnostic criteria for LPR, the sensitivity of NBI diagnostic method was 82.6%（157/190）, specificity 81.2%（69/85）, positive predictive value 90.8%（157/173） and negative predictive value 67.6%（69/102）. Conclusion:Narrow-band imaging, as a new endoscopic imaging technique, can show small changes in mucosal surface micro vessels and play an important role in the diagnosis of laryngopharyngeal reflux.

Association between Metabolic Syndrome and Risk of Hypopharyngeal Cancer: A Nationwide Cohort Study from Korea

This study evaluated the relationship between metabolic syndrome (MS) and the risk of hypopharyngeal cancer. This retrospective cohort study used data from the Korean National Health Insurance Research Database. A total of 4,567,890 participants who underwent a health checkup in 2008 were enrolled. The participants were followed until 2019, and the incidence of hypopharyngeal cancer was analyzed. We evaluated the risk of hypopharyngeal cancer according to the presence of MS, including obesity, dyslipidemia, hypertension, and diabetes, using a multivariate Cox proportional hazards model adjusted for age, sex, alcohol consumption, and smoking. During the follow-up period, 821 were newly diagnosed with hypopharyngeal cancer. MS was inversely associated with the risk of hypopharyngeal cancer (hazard ratio (HR), 0.83 [95% confidence interval (CI), 0.708-0.971]). Large waist circumference and high triglyceride levels among MS elements were both inversely related to the risk of hypopharyngeal cancer (HR: 0.82 [95% CI, 0.711-0.945] and 0.83 [95% CI, 0.703-0.978], respectively). The risk of hypopharyngeal cancer decreased with increasing comorbidity of MS in women (N = 0 vs. N = 1-2 vs. N ≥ 3; HR = 1 vs. HR = 0.511 [95% CI, 0.274-0.952] vs. HR = 0.295 [95% CI, 0.132-0.66]), but not in men. This study may improve our etiological understanding of hypopharyngeal cancer.

Diagnosis of Laryngopharyngeal Reflux Disease Based on Gray and Texture Changes of Laryngoscopic Images

OBJECTIVE

This study aimed to compare the changing trends of gray and texture values of laryngoscopic images in patients with laryngopharyngeal reflux (LPR) and non-LPR.

METHODS

A total of 3428 laryngoscopic images were selected and divided into two groups, non-LPR and LPR groups based on the reflux symptom index. Gray histogram and gray-level co-occurrence matrix (GLCM) were used to quantify gray and texture features, and the model was trained based on these features. The total laryngoscopic images dataset was proportionally split into two parts including the training set and the test set according to the ratio of 7:3. Four different machine learning algorithms, including decision tree, naive Bayes, linear regression, and K-nearest neighbors, were applied to classify non-LPR or LPR laryngoscopic images.

RESULTS

The results showed that different classification algorithms are used to classify laryngoscopic image dataset and promising classification accuracy are obtained. Specifically, the accuracy of K-nearest neighbors was 83.38% for the gray histogram-only classification, that of linear regression was 88.63% for the GLCM-only classification, and that of the decision tree was 98.01% for the combined gray histogram and GLCM analysis.

CONCLUSION

Gray histogram and GLCM analysis of the laryngoscopic images may be used as auxiliary tools to detect laryngopharyngeal mucosal damage in patients with LPR. Measurement of gray and texture feature values is an objective and convenient method, which may serve as a reference baseline for clinicians and have potential clinical usefulness.

Exosomal MicroRNA-223, MicroRNA-146, and MicroRNA-21 Profiles and Biochemical Changes in Laryngeal Cancer

Laryngeal squamous cell carcinoma (LSCC) is one of the most aggressive cancers, and its early diagnosis is urgent. Exosomes are believed to have diagnostic significance in cancer. However, the role of serum exosomal microRNAs, miR-223, miR-146, and miR-21, and phosphatase and tensin homologue (PTEN) and hemoglobin subunit delta (HBD) mRNAs in LSCC is unclear. Exosomes were isolated from the blood serum of 10 LSCC patients and 10 healthy controls to perform scanning electron microscopy and liquid chromatography quadrupole time-of-flight mass spectrometry analyses to characterize them and to undergo reverse transcription polymerase chain reaction to identify miR-223, miR-146, miR-21, and PTEN and HBD mRNA expression phenotypes. Biochemical parameters, including serum C-reactive protein (CRP) and vitamin B12, were also obtained. Serum exosomes of 10-140 nm were isolated from LSCC and controls. Serum exosomal miR-223, miR-146, and PTEN were found to be significantly decreased (p < 0.05), in contrast to serum exosomal miRNA-21 (p < 0.01), and serum vitamin B12 and CRP (p < 0.05) were found to be significantly increased, in LSCC vs controls. Our novel data show that the combination of reduced serum exosomal miR-223, miR-146, and miR-21 profiles and biochemical alterations in CRP and vitamin B12 levels may be useful indicators of LSCC that could be validated by large studies. Our findings also suggest a possible negative regulatory effect of miR-21 on PTEN in LSCC, encouraging a more extensive investigation of its role.

Sorafenib Alleviates Inflammatory Signaling of Tumor Microenvironment in Precancerous Lung Injuries

According to population-based studies, lung cancer is the prominent reason for cancer-related mortality worldwide in males and is also rising in females at an alarming rate. Sorafenib (SOR), which is approved for the treatment of hepatocellular carcinoma and renal cell carcinoma, is a multitargeted protein kinase inhibitor. Additionally, SOR is the subject of interest for preclinical and clinical trials in lung cancer. This study was designed to assess in vivo the possible effects of sorafenib (SOR) in diethylnitrosamine (DEN)-induced lung carcinogenesis and examine its probable mechanisms of action. A total of 30 adult male rats were divided into three groups (1) control, (2) DEN, and (3) DEN + SOR. The chemical induction of lung carcinogenesis was performed by injection of DEN intraperitoneally at 150 mg/kg once a week for two weeks. The DEN-administered rats were co-treated with SOR of 10 mg/kg by oral gavage for 42 alternate days. Serum and lung tissue samples were analyzed to determine SRY-box transcription factor 2 (SOX-2) levels. The tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) levels were measured in lung tissue supernatants. Lung sections were analyzed for cyclooxygenase-2 (COX-2) and c-Jun N-terminal kinase (JNK) histopathologically. In addition, cyclooxygenase-2 (COX-2) and c-Jun N-terminal kinase (JNK) were analyzed by immunohistochemistry and immunofluorescence methods, respectively. SOR reduced the level of SOX-2 that maintenance of cancer stemness and tumorigenicity, and TNF-α and IL-1β levels. Histopathological analysis demonstrated widespread inflammatory cell infiltration, disorganized alveolar structure, hyperemia in the vessels, and thickened alveolar walls in DEN-induced rats. The damage was markedly reduced upon SOR treatment. Further, immunohistochemical and immunofluorescence analysis also revealed increased expression of COX-2 and JNK expression in DEN-intoxicated rats. However, SOR treatment alleviated the expression of these inflammatory markers in DEN-induced lung carcinogenesis. These findings suggested that SOR inhibits DEN-induced lung precancerous lesions through decreased inflammation with concomitant in reduced SOX-2 levels, which enables the maintenance of cancer stem cell properties.

Renoprotective Effect of Taxifolin in Paracetamol-Induced Nephrotoxicity: Emerging Evidence from an Animal Model

BACKGROUND

Taxifolin (TXF) is a flavonoid found abundantly in citrus/onion. Encouraging results on its renoprotective effect have been reported in a limited number of drug-induced nephrotoxicity animal models. The present study aimed to evaluate for the first time the potential renoprotective effects of TXF in a paracetamol (PAR)-induced nephrotoxicity rat model.

METHODS

Rats were divided into three equal groups (n = 6 animals per group). Group 1 (PAR group, PARG) received PAR diluted in normal saline by gavage (1000 mg/kg). Group 2 (TXF group, TXFG) received TXF diluted in normal saline by gavage (50 mg/kg) one hour after PAR administration. Group 3 (control group, CG) received normal saline. Twenty-four hours after PAR administration, all animals were sacrificed using high-dose anesthesia. Blood samples were collected and kidneys were removed.

RESULTS

The serum blood urea nitrogen, creatinine levels and serum malondialdehyde levels were significantly increased in the PARG. The serum glutathione peroxidase, glutathione reductase and total glutathione levels were significantly higher in the TXFG. At the same time, the kidneys of the PARG animals demonstrated tubular epithelium swelling, distension and severe vacuolar degeneration. The kidneys of the TXFG animals showed mildly dilated/congested blood vessels.

CONCLUSIONS

The TXF renoprotective effects are promising in preventing PAR-induced nephrotoxicity, mainly through antioxidant activity, and warrant further testing in future studies.

The role of smoking and alcohol in mediating the effect of gastroesophageal reflux disease on lung cancer: A Mendelian randomization study

Observational studies have suggested a positive association between gastroesophageal reflux disease and lung cancer, but due to the existence of confounders, it remains undetermined whether gastroesophageal reflux disease (GERD) has a causal association with lung cancer. Therefore, Mendelian randomization (MR) analyses were applied to investigate the relationship between the two conditions. Two-sample Mendelian randomization analysis was utilized with summary genetic data from the European Bioinformatics Institute (602,604 individuals) and International Lung Cancer Consortium, which provides information on lung cancer and its histological subgroups. Furthermore, we used two-step Mendelian randomization and multivariable Mendelian randomization to estimate whether smoking initiation (311,629 cases and 321,173 controls) and alcohol intake frequency (n = 462,346) mediate any effect of gastroesophageal reflux disease on lung cancer risk. The Mendelian randomization analyses indicated that gastroesophageal reflux disease was associated with and significantly increased the risk of lung cancer (ORIVW = 1.35, 95% CI = 1.18-1.54; p = 1.36 × 10-5). Smoking initiation and alcohol intake frequency mediated 35% and 3% of the total effect of gastroesophageal reflux disease on lung cancer, respectively. The combined effect of these two factors accounted for 60% of the total effect. In conclusion, gastroesophageal reflux disease is associated with an increased risk of lung cancer, and interventions to reduce smoking and alcohol intake may reduce the incidence of lung cancer.

Bile acids as carcinogens in the colon and at other sites in the gastrointestinal system

Colon cancer incidence is associated with a high-fat diet. Such a diet is linked to elevated levels of bile acids in the gastrointestinal system and the circulation. Secondary bile acids are produced by microorganisms present at high concentrations in the colon. Recent prospective studies and a retrospective study in humans associate high circulating blood levels of secondary bile acids with increased risk of colon cancer. Feeding mice a diet containing a secondary bile acid, so their feces have the bile acid at a level comparable to that in the feces of humans on a high-fat diet, also causes colon cancer in the mice. Studies using human cells grown in culture illuminate some mechanisms by which bile acids cause cancer. In human cells, bile acids cause oxidative stress leading to oxidative DNA damage. Increased DNA damage increases the occurrence of mutations and epimutations, some of which provide a cellular growth advantage such as apoptosis resistance. Cells with such mutations/epimutations increase by natural selection. Apoptosis, or programmed cell death, is a beneficial process that eliminates cells with unrepaired DNA damage, whereas apoptosis-resistant cells are able to survive DNA damage using inaccurate repair processes. This results in apoptosis-resistant cells having more frequent mutations/epimutations, some of which are carcinogenic. The experiments on cultured human cells have provided a basis for understanding at the molecular level the human studies that recently reported an association of bile acids with colon cancer, and the mouse studies showing directly that bile acids cause colon cancer. Similar, but more limited, findings of an association of dietary bile acids with other cancers of the gastrointestinal system suggest that understanding the role of bile acids in colon carcinogenesis may contribute to understanding carcinogenesis in other organs.

Bile reflux alters the profile of the gastric mucosa microbiota

BACKGROUND

Bile reflux can cause inflammation, gastric mucosa atrophy, and diseases such as stomach cancer. Alkaline bile flowing back into the stomach affects the intragastric environment and can alter the gastric bacterial community. We sought to identify the characteristics of the stomach mucosal microbiota in patients with bile reflux.

METHODS

Gastric mucosal samples were collected from 52 and 40 chronic gastritis patients with and without bile reflux, respectively. The bacterial profile was determined using 16S rRNA gene analysis.

RESULTS

In the absence of H. pylori infection, the richness (based on the Sobs and Chao1 indices; P <0.05) and diversity (based on Shannon indices; P <0.05) of gastric mucosa microbiota were higher in patients with bile reflux patients than in those without. There was a marked difference in the microbiota structure between patients with and without bile reflux (ANOSIM, R=0.058, P=0.011). While the genera, Comamonas, Halomonas, Bradymonas, Pseudomonas, Marinobacter, Arthrobacter, and Shewanella were enriched in patients with bile reflux, the genera, Haemophilus, Porphyromonas, and Subdoligranulum, were enriched in those without bile reflux.

CONCLUSION

Our results demonstrate that bile reflux significantly alters the composition of the gastric microbiota.

The Role of PARP ‐1 and NF‐κB in Bile‐Induced DNA Damage and Oncogenic Profile in Hypopharyngeal Cells

OBJECTIVES/HYPOTHESIS

We recently documented that acidic bile, a gastroesophageal reflux content, can cause invasive hypopharyngeal squamous cell carcinoma, by inducing widespread DNA damage and promoting nuclear factor kappa B (NF-κB)-related oncogenic molecular events. Poly or adenosine diphosphate (ADP)-ribose polymerase-1 (PARP-1), a sensitive sensor of DNA damage, may interact with NF-κB. We hypothesized that PARP-1 is activated in hypopharyngeal cells (HCs) with marked DNA damage caused by acidic bile, hence there is an association between PARP-1 and NF-κB activation or its related oncogenic profile, in this process.

STUDY DESIGN

In vitro study.

METHODS

We targeted PARP-1 and NF-κB(p65), using pharmacologic inhibitors, 1.0 μM Rucaparib (AG014699) and 10 μM BAY 11-7082 {3-[4=methylphenyl)sulfonyl]-(2E)-propenenitrile}, respectively, or silencing their gene expression (siRNAs) and used immunofluorescence, luciferase, cell viability, direct enzyme-linked immunosorbent assays, and qPCR analysis to detect the effect of targeting PARP-1 or NF-κB in acidic bile-induced DNA damage, PARP-1, p-NF-κB, and B-cell lymphoma 2 (Bcl-2) expression, as well as NF-κB transcriptional activity, cell survival, and mRNA oncogenic phenotype in HCs.

RESULTS

We showed that (i) PARP-1 is overexpressed by acidic bile, (ii) targeting NF-κB adequately prevents the acidic bile-induced DNA double-strand breaks (DSBs) by gamma H2A histone family member X (γH2AX), oxidative DNA/RNA damage, PARP-1 overexpression, anti-apoptotic mRNA phenotype, and cell survival, whereas (iii) targeting PARP-1 preserves elevated DNA damage, NF-κB activation, and anti-apoptotic phenotype.

CONCLUSION

We document for the first time that the activation of PARP-1 is an early event during bile reflux-related head and neck carcinogenesis and that NF-κB can mediate DNA damage and PARP-1 activation. Our data encourage further investigation into how acidic bile-induced activated NF-κB mediates DNA damage in hypopharyngeal carcinogenesis.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:1146-1155, 2023.

Noxious Combination of Tobacco Smoke Nitrosamines with Bile, Deoxycholic Acid, Promotes Hypopharyngeal Squamous Cell Carcinoma, via NFκB, In Vivo

Tobacco smoking is the most known risk factor for hypopharyngeal cancer. Bile reflux has recently been documented as an independent risk factor for NFκB-mediated hypopharyngeal squamous cell carcinoma. However, the carcinogenic effect of tobacco smoke on the hypopharynx and its combination with bile has not yet been proven by direct evidence. We investigated whether in vivo chronic exposure (12-14 weeks) of murine (C57Bl/6J) hypopharyngeal epithelium to tobacco smoke components (TSC) [N-nitrosamines; 4-(N-Methyl-N-Nitrosamino)-1-(3-pyridyl)-1-butanone (0.2 mmol/L), N-nitrosodiethylamine (0.004 mmol/L)], as the sole drinking fluid 5 days per week, along with topically applied (two times/day) bile [deoxycholic acid (0.28 mmol/L)], can accelerate a possible TSC-induced neoplastic process, by enhancing NFκB activation and the associated oncogenic profile, using histologic, IHC, and qPCR analyses. We provide direct evidence of TSC-induced premalignant lesions, which can be exacerbated by the presence of bile, causing invasive carcinoma. The combined chronic exposure of the hypopharynx to TSC with bile causes advanced NFκB activation and profound overexpression of Il6, Tnf, Stat3, Egfr, Wnt5a, composing an aggressive phenotype. We document for the first time the noxious combination of bile with a known risk factor, such as tobacco smoke nitrosamines, in the development and progression of hypopharyngeal cancer, via NFκB, in vivo. The data presented here encourage further investigation into the incidence of upper aerodigestive tract cancers in smokers with bile reflux and the early identification of high-risk individuals in clinical practice. This in vivo model is also suitable for large-scale studies to reveal the nature of inflammatory-associated aerodigestive tract carcinogenesis and its targeted therapy.

PREVENTION RELEVANCE

Early assessment of bile components in refluxate of tobacco users can prevent the chronic silent progression of upper aerodigestive tract carcinogenesis. This in vivo model indicates that bile reflux might have an additive effect on the tobacco-smoke N-nitrosamines effect and could be suitable for large-scale studies of diagnostic and therapeutic interventions.

Bile Reflux After Single Anastomosis Duodenal-Ileal Bypass with Sleeve (SADI-S): a Meta-analysis of 2,029 Patients

BACKGROUND

Single anastomosis duodenal-ileal bypass with sleeve (SADI-S) is a novel bariatric surgery modified from the classic biliopancreatic diversion with duodenal switch (BPD-DS). These surgical modifications address most BPD-DS hurdles, but the risk of bile reflux may hinder SADI-S acceptance. We aimed to evaluate the event rate of bile reflux after SADI-S.

METHODS

PubMed, ScienceDirect, Cochrane, Web of Science, and Google Scholar were used to search English articles between 2008 and 2021 by two independent reviewers using the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). The risk of bias was assessed using Newcastle-Ottawa Scale and the JBI tool. Event rates were meta-analyzed using Comprehensive Meta-Analysis (CME) V3.

RESULTS

Out of 3,027 studies analyzed, seven were included. Studies were published between 2010 and 2020. Six out of 7 studies were retrospective. Three studies had a low risk of bias, three studies had a moderate risk of bias, and one had a high risk of bias. The mean follow-up was 10.3 months. The total number of patients was 2,029, with 25 reports of bile reflux, resulting in an incidence of 1.23%, with an event rate of 0.016 (95% CI 0.004 to 0.055).

CONCLUSIONS

Bile reflux has not been demonstrated to be problematic after SADI-S in this meta-analysis. Further long-term studies are needed.

Targeting STAT3 prevents bile reflux-induced oncogenic molecular events linked to hypopharyngeal carcinogenesis

The signal transducer and activator of transcription 3 (STAT3) oncogene is a transcription factor with a central role in head and neck cancer. Hypopharyngeal cells (HCs) exposed to acidic bile present aberrant activation of STAT3, possibly contributing to its oncogenic effect. We hypothesized that STAT3 contributes substantially to the bile reflux‐induced molecular oncogenic profile, which can be suppressed by STAT3 silencing or pharmacological inhibition. To explore our hypothesis, we targeted the STAT3 pathway, by knocking down STAT3 (STAT3 siRNA), and inhibiting STAT3 phosphorylation (Nifuroxazide) or dimerization (SI3‐201; STA‐21), in acidic bile (pH 4.0)‐exposed human HCs. Immunofluorescence, luciferase assay, Western blot, enzyme‐linked immunosorbent assay and qPCR analyses revealed that STAT3 knockdown or pharmacologic inhibition significantly suppressed acidic bile‐induced STAT3 activation and its transcriptional activity, Bcl‐2 overexpression, transcriptional activation of IL6, TNF‐α, BCL2, EGFR, STAT3, RELA(p65), REL and WNT5A, and cell survival. Our novel findings document the important role of STAT3 in bile reflux‐related molecular oncogenic events, which can be dramatically prevented by STAT3 silencing. STA‐21, SI3‐201 or Nifuroxazide effectively inhibited STAT3 and cancer‐related inflammatory phenotype, encouraging their single or combined application in preventive or therapeutic strategies of bile reflux‐related hypopharyngeal carcinogenesis.