The cadherin-catenin complex in laryngeal squamous cell carcinoma

Pepsin Inhibitors Prevent Inflammation and Loss of Laryngeal Barrier Function in Mice with Gastroesophageal Reflux

OBJECTIVE

This study aimed to evaluate the role of pepsin inhibitors in the inflammatory response and their effects on laryngeal mucosal integrity during gastroesophageal reflux (GERD) under in vivo conditions.

METHODS

A surgical model of GERD was used, in which mice were treated with pepstatin (0.3 mg/kg) or darunavir (8.6 mg/kg) for 3 days. On the third day after the experimental protocol, the laryngeal samples were collected to assess the severity of inflammation (wet weight and myeloperoxidase activity) and mucosal integrity (transepithelial electrical resistance and paracellular epithelial permeability to fluorescein).

RESULTS

The surgical GERD model was reproduced. It showed features of inflammation and loss of barrier function in the laryngeal mucosa. Pepstatin and darunavir administration suppressed laryngeal inflammation and preserved laryngeal mucosal integrity.

CONCLUSION

Pepsin inhibition by the administration of pepstatin and darunavir improved inflammation and protected the laryngeal mucosa in a mouse experimental model of GERD.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:3080-3085, 2024.

Overview on Molecular Biomarkers for Laryngeal Cancer: Looking for New Answers to an Old Problem

Laryngeal squamous cell cancer (LSCC) accounts for almost 25-30% of all head and neck squamous cell cancers and is clustered according to the affected districts, as this determines distinct tendency to recur and metastasize. A major role for numerous genetic alterations in driving the onset and progression of this neoplasm is emerging. However, major efforts are still required for the identification of molecular markers useful for both early diagnosis and prognostic definition of LSCC that is still characterized by significant morbidity and mortality. Non-coding RNAs appear the most promising as they circulate in all the biological fluids allowing liquid biopsy determination, as well as due to their quick and characteristic modulation useful for non-invasive detection and monitoring of cancer. Other critical aspects are related to recent progress in circulating tumor cells and DNA detection, in metastatic status and chemo-refractoriness prediction, and in the functional interaction of LSCC with chronic inflammation and innate immunity. We review all these aspects taking into account the progress of the technologies in the field of next generation sequencing.

Effects of acids, pepsin, bile acids, and trypsin on laryngopharyngeal reflux diseases: physiopathology and therapeutic targets

PURPOSE

Laryngopharyngeal reflux disease (LPRD) is a general term for the reflux of gastroduodenal contents into the laryngopharynx, oropharynx and even the nasopharynx, causing a series of symptoms and signs. Currently, little is known regarding the physiopathology of LPRD, and proton pump inhibitors (PPIs) are the drugs of choice for treatment. Although acid reflux plays a critical role in LPRD, PPIs fail to relieve symptoms in up to 40% of patients with LPRD. The influence of other reflux substances on LPRD, including pepsin, bile acid, and trypsin, has received increasing attention. Clarification of the substances involved in LPRD is the basis for LPRD treatment.

METHODS

A review of the effects of acids, pepsin, bile acids, and trypsin on laryngopharyngeal reflux diseases was conducted in PubMed.

RESULTS

Different reflux substances have different effects on LPRD, which will cause various symptoms, inflammatory diseases and neoplastic diseases of the laryngopharynx. For LPRD caused by different reflux substances, 24-h multichannel intraluminal impedance combined with pH-metry (MII-pH), salivary pepsin, bile acid and other tests should be established so that different drugs and treatment courses can be used to provide patients with more personalized treatment plans.

CONCLUSION

This article summarizes the research progress of different reflux substances on the pathogenesis, detection index and treatment of LPRD and lays a theoretical foundation to develop target drugs and clinical diagnosis and treatment.

Pepsin and Laryngeal and Hypopharyngeal Carcinomas

Laryngeal and hypopharyngeal carcinomas are common malignant tumors of the head and neck, and the incidence of both is increasing. Laryngopharyngeal reflux refers to the retrograde flow of gastric contents into the larynx, oropharynx, and/or nasopharynx. It remains controversial whether laryngopharyngeal reflux is a risk factor for laryngeal and hypopharyngeal cancers. The refluxing substances mainly include hydrochloric acid, pepsin, and occasionally bile acids and bile salts, as well as bacteria that colonize the gastrointestinal tract. Loss of epithelium in the mucous membrane of the larynx and hypopharynx is thought to be caused by pepsin. Here, we review the relationships between laryngopharyngeal reflux and both laryngeal and hypopharyngeal carcinomas, as well as the significance of pepsin, methods of clinical detection, and the mechanism of carcinogenesis.

Relationship Between Pepsin Expression and Dysplasia Grade in Patients With Vocal Cord Leukoplakia

OBJECTIVE

To measure pepsin expression in patients with vocal fold leukoplakia and elucidate its clinical significance.

STUDY DESIGN

Retrospective analysis of pathologic archive specimens.

SETTING

Affiliated university hospital.

SUBJECTS AND METHODS

The study included 45 patients with vocal fold leukoplakia and 19 with vocal fold polyps who underwent surgical treatment between December 2013 and July 2016. Masses were detected on both vocal cords in 5 patients with vocal fold leukoplakia and in 1 patient with vocal fold polyps. Immunohistochemistry was used to assess pepsin expression. In addition, the relationship of pepsin expression level with clinical characteristics of vocal fold leukoplakia was assessed.

RESULTS

The rate of pepsin expression was high in the polyp group (75%) and the leukoplakia group (68%); however, the difference between groups was not significant (P > .05). Pepsin expression significantly increased according to grade of dysplasia (mild, 57.1%; moderate, 88.9%; severe, 100.0%; P = .034). Similarly, the percentage of lesions that exhibited strongly positive pepsin expression increased with the grade of dysplasia (mild, 37.1%; moderate, 66.7%; severe, 100.0%; P = .005). The leukoplakia recurrence rate was higher in patients with positive pepsin expression than in patients with negative pepsin expression but without a significant difference (P > .05).

CONCLUSION

Our study suggests that pepsin was associated with the grade of dysplasia of vocal cord leukoplakia. Further investigation with appropriate control groups and controlling for other risk factors, such as smoking or alcohol consumption, is needed.

The Significance of the Dysregulation of Canonical Wnt Signaling in Head and Neck Squamous Cell Carcinomas

The knowledge about the molecular alterations which are found in head and neck squamous cell carcinomas (HNSCC) has much increased in recent years. However, we are still awaiting the translation of this knowledge to new diagnostic and therapeutic options. Among the many molecular changes that are detected in head and neck cancer, the abnormalities in several signaling pathways, which regulate cell proliferation, cell death and stemness, seem to be especially promising with regard to the development of targeted therapies. Canonical Wnt signaling is a pathway engaged in the formation of head and neck tissues, however it is not active in adult somatic mucosal cells. The aim of this review paper is to bring together significant data related to the current knowledge on the mechanisms and functional significance of the dysregulation of the Wnt/β-catenin pathway in head and neck tumors. Research evidence related to the role of Wnt signaling activation in the stimulation of cell proliferation, migration and inhibition of apoptosis in HNSCC is presented. Moreover, its role in promoting stemness traits in head and neck cancer stem-like cells is described. Evidence corroborating the hypothesis that the Wnt signaling pathway is a very promising target of novel therapeutic interventions in HNSCC is also discussed.

Distinct Biomarker Profiles and Clinical Characteristics in T1-T2 Glottic and Supraglottic Carcinomas

Background

In early stage laryngeal squamous cell carcinoma (LSCC) radiotherapy with curative intent is a major treatment modality. TNM classification is used to define patients eligible for radiotherapy. Studies in early stage glottic LSCC identified several predictive biomarkers associated with local control. However, we recently reported that this predictive value could not be confirmed in supraglottic LSCC.

Objective

To examine whether clinical behavior and protein expression patterns of these biomarkers differ between glottic and supraglottic LSCC.

Study Design

Retrospective cohort study.

Methods

Tumor tissue sections of 196 glottic and 80 supraglottic T1‐T2 LSCC treated primarily with RT were assessed immunohistochemically for expression of pAKT, Ki‐67 and β‐Catenin. Expression data of HIF‐1α, CA‐IX, OPN, FADD, pFADD, Cyclin D1, Cortactin and EGFR in the same cohort of glottic and supraglottic LSCC, were retrieved from previously reported data. The relationship between glottic and supraglottic sublocalization and clinicopathological, follow‐up, and immunohistochemical staining characteristics were evaluated using logistic regression and Cox regression analyses.

Results

Glottic LSCC were correlated with male gender (P = .001), hoarseness as a primary symptom (P < .001), T1 tumor stage (P < .001), negative lymph node status (P < .001), and an older age at presentation (P = .004). Supraglottic LSCC patients developed more post‐treatment distant metastasis when adjusted for gender, age, and T‐status. While supraglottic LSCC was associated with higher expression of HIF‐1α (P = .001), Cortactin (P < .001), EGFR (P < .001), and Ki‐67 (P = .027), glottic LSCC demonstrated higher expression of CA‐IX (P = .005) and Cyclin D1 (P = .001).

Conclusion

Differences in clinicopathological and immunohistochemical staining characteristics suggest that T1‐T2 glottic and supraglottic LSCC should be considered as different entities.

Level of Evidence

N/A. Laryngoscope, 2020

Pepsin promotes IL-8 signaling-induced epithelial-mesenchymal transition in laryngeal carcinoma

Background

Laryngopharyngeal reflux (LPR), with its increasing morbidity, is attracting considerable attention. In recent years, the causal role between LPR and laryngeal carcinoma has been debated. The main harmful component of LPR is pepsin, which has been shown to induce mucosal inflammation by damaging the mucous membrane. Thus, pepsin is linked to an increased risk of laryngeal carcinoma, although the potential mechanism remains largely unknown.

Methods

The human laryngeal carcinoma cell lines Hep-2 and Tu212 were exposed to different pepsin concentrations and the morphology, proliferation, migration, secretion of inflammatory cytokines, and epithelial–mesenchymal transition (EMT) of the cells were assessed. To evaluate whether interleukin-8 (IL-8) had a causal relationship with pepsin and EMT, an IL-8 inhibitor was used to suppress IL-8 secretion during pepsin exposure and the expression of EMT markers, cell proliferation, and migration were analyzed.

Results

Pepsin promoted proliferation, colony formation, migration, and IL-8 secretion of Hep-2 and Tu212 cells in vitro. Furthermore, increased pepsin concentrations changed the morphology of Hep-2 and Tu212 cells; levels of the epithelial marker E-cadherin were reduced and those of mesenchymal markers vimentin and β-catenin and the transcription factors snail and slug were elevated. A similar effect was observed in laryngeal carcinoma tissues using immunohistochemistry. IL-8 level was reduced and EMT was restored when pepsin was inhibited by pepstatin. EMT was weakened after exposure to the IL-8 inhibitor, with significant reduction in pepsin-induced cell proliferation and migration.

Conclusions

Pepsin may induce EMT in laryngeal carcinoma through the IL-8 signaling pathway, which indicates that it has potential role in enhancing cell proliferation and metastasis of laryngeal carcinoma.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0772-7) contains supplementary material, which is available to authorized users.

Clinical significance of epithelial-to-mesenchymal transition in laryngeal carcinoma: Its role in the different subsites

BACKGROUND

During epithelial-to-mesenchymal transition, cancer cells lose adhesion capacity gaining migratory properties. The role of the process on prognosis has been evaluated in 50 cases of laryngeal carcinoma.

METHODS

E-cadherin, N-cadherin, β-catenin, α-catenin, γ-catenin, caveolin-1, and vimentin immunohistochemical expression were evaluated using a double score based on staining intensity and cellular localization.

RESULTS

Cytoplasmic E-cadherin and α/γ catenin staining were associated with a decrease in survival, cytoplasmic β-catenin was associated with advanced stage, and N-cadherin and vimentin expression were associated with poor differentiation and tumor relapse. On the basis of cancer cells, epithelial or mesenchymal morphological and immunophenotypic similarity we identified 4 main subgroups correlated with a transition to a more undifferentiated phenotype, which have a different pattern of relapse and survival.

CONCLUSION

The negative prognostic role of epithelial-to-mesenchymal transition has been confirmed and a predictive role in glottic tumors has been suggested, leading us to propose epithelial-to-mesenchymal transition as an additional adverse feature in laryngeal carcinoma.

New miRNA expression abnormalities in laryngeal squamous cell carcinoma

BACKGROUND

Although the development of novel diagnostic and treatment strategies concerning laryngeal cancer is highly intensive, the survival rate remains virtually unchanged. Small non-coding RNAs appear to be very promising biomarkers - and so remain the focus of extensive investigation in laryngeal cancer.

OBJECTIVE

We examined the expression of five miRNA and five genes related to cancer whether they could be potential laryngeal cancer biomarkers.

METHODS

We performed an analysis in 47 patients diagnosed with laryngeal cancer. The qPCR technique was used to investigate the expression profile.

RESULTS

While miR-21-3p and miR-525-5p were found to be significantly up-regulated, miR-139-3p and miR-885-5p expression is lower in laryngeal cancer. Moreover, PIK3R1 and HACE1 were found to be also down-regulated.

CONCLUSIONS

The change in miRNA expression is frequent than the expression of other tested genes. The expression of passenger strands such as miR-21-3p and miR-139-3p, which are rarely investigated, is also significantly affected in laryngeal cancer. While PIK3R1, HACE1, miR-139-3p, and miR-885-5p may act as tumor suppressor genes in the studied tumour type, miR-21-3p and miR-525-5p seem to have oncogenic properties. Our findings suggest that miR-885-5p and PIK3R1 are the best indicators for the classification of laryngeal cancer tissue and normal mucosa.

Basement membrane protein ladinin-1 and the MIF-CD44-β1 integrin signaling axis are implicated in laryngeal cancer metastasis

Laryngeal squamous cell carcinoma (LSCC) is the most common form of malignant disease in the head and neck region characterized by frequent occurrence of metastases in the neck lymph nodes early in the disease onset. In the presented study, we performed quantitative proteomic profiling of patient-matched primary tumor and adjacent non-tumorous tissues derived from metastatic LSCC as to identify new protein candidates with potential diagnostic and therapeutic significance. Obtained results revealed for the first time involvement of the basement membrane protein ladinin-1 in laryngeal cancer metastases. Alterations in the cellular microenvironment that propel metastatic events in laryngeal cancer include activation of MIF-CD44-β1 integrin signal transduction pathway and induction of downstream signaling mediated by NF-κB and Src tyrosine kinase, which ultimately impinge on cytoskeletal dynamics and architecture resulting in increased cellular motility and invasiveness. In this context, particularly interesting finding is upregulation of several actin-binding proteins novel to laryngeal cancer pathogenesis including coronin-1C and plastin-2, whose functional significance in laryngeal carcinogenesis has yet to be established. We also detected for the first time a complete loss of afamin in metastatic laryngeal cancer tissues, which warrants further studies into its use as a possible marker for monitoring disease progression and/or treatment outcome.

Altered β-catenin expression in oral mucosal dysplasia: a comparative study

OBJECTIVE

The current study aimed to investigate the β-catenin expression in oral leukoplakia (OL) with different degrees of epithelial dysplasia and normal oral mucosa.

MATERIAL AND METHODS

Formalin-fixed, paraffin-embedded tissue samples of 39 OL (mild dysplasia n=19, moderate dysplasia n=13, and severe dysplasia n=7), and 10 normal oral mucosa (control group) were submitted to immunohistochemical reactions to anti-β-catenin primary antibody. A qualitative β-catenin analysis was performed based on the percentage of positive cells. The cellular location and the epithelial layer were also considered. The Chi-square test and the Fisher's exact test were used to verify possible differences in the β-catenin expression among the OL groups. A p-value of <0.05 was considered statistically significant.

RESULTS

Membranous expression of β-catenin in parabasal and basal layers was gradually lost in the higher degrees of epithelial dysplasia. In normal oral mucosa, β-catenin was detected only in the cytoplasmic membrane. However, a significant increase in cytoplasmic β-catenin could be observed between mild and moderate dysplasia (Fisher Exact test - p<0.001) and between mild and severe dysplasia (p<0.001).

CONCLUSIONS

The β-catenin cytoplasmic expression observed in this study may represent the initial stage of modifications in the E-cadherin-catenin complex, along with morphological cellular changes.

The prognostic role of E-cadherin and β-catenin overexpression in laryngeal squamous cell carcinoma

OBJECTIVES/HYPOTHESIS

Epithelial-to-mesenchymal transition (EMT) consists of a rapid and reversible change in the cellular phenotype toward the mesenchymal cell phenotype that facilitates cell migration and invasion of the tumor into surrounding tissues followed by metastasis. In the present study, we sought to determine the clinical significance of E-cadherin, N-cadherin, β-catenin, α-catenin, γ-catenin, caveolin-1, and vimentin in a cohort of patients with stage I to IVA laryngeal squamous cell carcinoma (LSCC) treated with surgery with or without adjuvant therapy using immunohistochemical analyses.

STUDY DESIGN

Individual retrospective cohort study.

METHODS

E-cadherin, N-cadherin, β-catenin, α-catenin, γ-catenin, caveolin-1, and vimentin immunohistochemical expression were evaluated in a cohort of 82 patients with stages I to IVA LSCC. The Fisher exact test was used for categorical variables, and the Mann-Whitney test where appropriate for continuous variables. Survival comparisons was performed using the log-rank test. A multivariate analysis using the Cox proportional hazards model was performed and considered all EMT markers.

RESULTS

In multivariate analysis, T stage was an independent risk factor for adverse disease-specific survival (DSS) and overall survival (OS) (P = .025 and .019, respectively). Cytoplasmic β-catenin overexpression was independently associated with a longer DSS (P = .0007), and E-cadherin overexpression was found to be an independent risk factor for poor OS (P = .030).

CONCLUSIONS

E-cadherin and β-catenin pathways could represent future therapeutic targets in the treatment of LSCC. However, validation of our results in prospective cohorts of patients with LSCCs is required before their clinical implementation.

LEVEL OF EVIDENCE

NA.

Chronic pepsin exposure promotes anchorage-independent growth and migration of a hypopharyngeal squamous cell line

OUTCOME OBJECTIVES

(1) Investigate the role of reflux, specifically pepsin, in laryngopharyngeal carcinogenesis. (2) Evaluate effects of chronic pepsin exposure on cell migration, apoptosis, and colony-forming ability in hypopharyngeal cells.

STUDY DESIGN

Translation research.

SETTING

Academic research laboratory.

METHODS

Human hypopharyngeal squamous carcinoma FaDu cells were chronically exposed to nonacidic pepsin (exposed for 24 hours, 4 times over 2 weeks at the following concentrations: 0.01 mg/mL, 0.1 mg/mL, or 1 mg/mL). Precise wounds were created in confluent cell plates, and rates of cell migration into wounds were quantified. Separately, cell viability of chronic pepsin-exposed FaDu cells acutely treated with paclitaxel was measured. Finally, a clonogenic assay was performed on these cells to measure effects of chronic pepsin exposure on colony-forming ability.

RESULTS

An increased rate of relative wound density was observed in chronic pepsin-treated (0.01 mg/mL, 0.1 mg/mL) cells compared with control (P < .001), suggesting greater rates of cell migration. Pepsin-treated (0.1 mg/mL) cells demonstrated on average greater cell viability compared with control after exposure to paclitaxel, suggesting possible apoptotic resistance; however, this was not statistically significant. Chronic pepsin exposure (0.1 mg/mL, 1 mg/mL) was associated with a dose-dependent increase in colony-forming ability relative to control (P < .001).

CONCLUSION

Hypopharyngeal squamous cell line chronically exposed to pepsin demonstrated increased cell migration and colony-forming ability relative to control cells. These experiments indicate that chronic pepsin exposure acts as a promoter of tumorigenesis and metastasis of airway epithelium, suggesting a role for pepsin in laryngopharyngeal carcinogenesis attributed to gastric reflux.

Genetic and protein markers related to laryngeal epithelial precursor lesions and their neoplastic progression

CONCLUSION

Various biomarkers might ultimately prove to have prognostic value and could be clinically relevant. It is mandatory confirm the prognostic power of these markers in large, well-designed, and prospective studies.

OBJECTIVE

The aim of this study was to investigate the possible role of specific genes and proteins in laryngeal tumorigenesis.

METHODS

Genetic analysis by multiple ligation-dependent probe amplification and analysis of protein expression by immunohistochemistry were carried out in a series of 50 tissue samples.

RESULTS

In the smoker normal mucosa group TP53 loss was predominant, whereas in the epithelial precursor lesions (EPLs) CDKN2A loss and BCL2L1 gain were most frequent. EPL with progression presented CTNNB1 loss. Positivity at cytoplasm for β-catenin, cyclin D1 and p53 was detected in all EPL cases with progression to invasive carcinoma. Multivariate analysis showed that expression of β-catenin and loss of CTTNB1 were associated with laryngeal cancer risk.

Epigenetic dysregulation in laryngeal squamous cell carcinoma

Laryngeal carcinoma is a common head and neck cancer with poor prognosis. Patients with laryngeal carcinoma usually present late leading to the reduced treatment efficacy and high rate of recurrence. Despite the advance in the use of molecular markers for monitoring human cancers in the past decades, there are still no reliable markers for use to screen laryngeal carcinoma and follow the patients after treatment. Epigenetics emerged as an important field in understanding the biology of the human malignancies. Epigenetic alterations refer to the dysregulation of gene, which do not involve the alterations of the DNA sequence. Major epigenetic changes including methylation imbalance, histone modification, and small RNA dysregulation could play a role in the development of human malignancies. Global epigenetic change is now regarded as a molecular signature of cancer. The characteristics and behavior of a cancer could be predicted based on the specific epigenetic pattern. We here provide a review on the understanding of epigenetic dysregulation in laryngeal carcinoma. Further knowledge on the initiation and progression of laryngeal carcinoma at epigenetic level could promote the translation of the knowledge to clinical use.