RNA Sequencing Reveals Cancer-Associated Changes in Laryngeal Cells Exposed to Non-Acid Pepsin.

OBJECTIVE: Laryngopharyngeal reflux (LPR) is a common affliction that contributes to laryngeal inflammation, symptoms that impact quality of life, and life-threatening illnesses such as cancer. Effective treatment strategies for LPR are lacking. Pepsin is a proinflammatory and carcinogenic element of refluxate. Investigation of molecular pathways involved in pepsin-mediated damage may lead to identification of novel biomarkers and therapeutic targets for LPR. In this study, RNA sequencing was used to examine changes in human laryngeal epithelial cells following brief pepsin insult. Cells were immortalized to generate a model to aid future study of laryngeal injury and therapeutics. STUDY DESIGN: In vitro translational. METHODS: Laryngeal epithelial cells were cultured from a patient without signs or symptoms of LPR or laryngeal cancer. Cells were treated with 0.1 mg/ml pepsin for 1 hour or normal growth media (control) prior to RNA sequencing. Cells were immortalized via HPV E6/7 and characterized by microscopy, immunohistochemistry, G-banding, and soft agar assay. RESULTS: Three hundred ninety-seven genes exhibited differences in expression with pepsin treatment (P < .05). Pathway analysis revealed association with cancer and related signaling processes including dysregulation of cancer-associated molecules, Metastasis-Associated Lung Adenocarcinoma Transcript 1 and KRT82, and the long-noncoding RNA, lipoprotein receptor-related protein 1 (LRP1)-AS, which regulates the putative pepsin receptor LRP1. CONCLUSIONS: A single, brief exposure to pepsin activated cancer-associated signaling pathways in laryngeal cells in vitro, revealing novel mechanisms by which chronic reflux may contribute to carcinogenesis. The cell line developed herein represents a novel tool in which to investigate pepsin-dysregulated pathways identified by RNA sequencing and disparities of tumor proneness of laryngeal subsites. LEVEL OF EVIDENCE: N/A Laryngoscope, 131:121-129, 2021.

Advances in Surgery: Extended Procedures for Sinonasal Polyp Disease.

In the standard functional endoscopic sinus surgery (FESS) procedure, the amount of dissection is often determined by the extent of disease with the goal to preserve as much normal mucosa as possible while restoring ventilation and reestablishing mucociliary clearance. A subset of patients with chronic rhinosinusitis with nasal polyposis (CRSwNP), however, may continue to have persistent mucosal inflammatory and aggressive polyp regrowth despite standard FESS and maximal pharmacology therapy, leading to recurrent and recalcitrant disease. Advanced endoscopic surgery techniques such as the modified endoscopic medial maxillectomy, endoscopic modified Lothrop procedure, otherwise known as a Draf 3 frontal sinusotomy, and nasalisation or radical ethmoidectomy are extensive surgical procedures to maximize disease clearance while providing sizeable drainage pathways for effective postoperative surveillance and topical delivery of medications. Studies have shown a decreased risk of revision surgery as well as a longer time interval for revision surgery in patients with refractory CRSwNP who have undergone extensive sinus surgery for polyps.

Venous malformation of the ethmoid and sphenoid sinuses.

OBJECTIVES: The aim of this study was to present a rare case of a venous malformation that occupied the ethmoid and sphenoid sinuses. Prior to resection, it was believed to be a hemangioma. METHODS: This study includes a case report and review of the literature. CONCLUSION: There is often confusion between "hemangiomas" and "vascular malformations," but they are important to differentiate because they have unique approaches to treatment. Venous malformations in the paranasal sinuses are very rare. To our knowledge, this is the first case report that explicitly describes a venous malformation in the ethmoid and sphenoid sinuses. It was treated using endoscopic sinus surgery with intraoperative computer-assisted stereotactic navigation.

The Impact of Pepsin on Human Nasal Epithelial Cells In Vitro: A Potential Mechanism for Extraesophageal Reflux Induced Chronic Rhinosinusitis.

OBJECTIVES: To describe potential mechanisms by which pepsin induces inflammation in refractive chronic rhinosinusitis (CRS). Our hypothesis was that pepsin induces mitochondrial damage and cytokine expression in human nasal epithelial cells (HNEpC) in vitro. METHODS: Western blot was used to detect pepsin in sinus lavages from patients with CRS and controls. The HNEpC cells were treated with pepsin (pH 7; 0.1 mg/mL) for 1 or 16 hours and routine electron microscopy (EM) and MTT assay were performed. Cytokine ELISA was performed on media collected from HNEpC cells 16 hours following a 1-hour pepsin treatment. RESULTS: Pepsin was detected in sinus lavages from 4 out of 6 CRS patients and 0 out of 3 controls. The EM showed mitochondrial damage in pepsin-treated HNEpC cells but not in control cells. The MTT assay demonstrated reduced mitochondrial activity in pepsin-treated HNEpC cells compared to controls (P < .001). Pepsin increased IL-1A (P = .003) and IL-6 (P = .04) expression in HNEpC cells. CONCLUSIONS: Pepsin in sinus lavages from patients with CRS is consistent with previous studies. This study reveals the damaging effect of pepsin on mitochondria in nasal epithelial cells in vitro. Cytokines previously associated with CRS were elevated following pepsin treatment of HNEpC cells in vitro. These results demonstrate mechanisms by which pepsin may potentiate CRS.