Objectives/Hypothesis To assess if there is a significant difference in the prevalence and severity of chronic cough symptoms in obstructive sleep apnea (OSA) patients versus non‐OSA patients and examine this relationship in regard to laryngopharyngeal reflux (LPR) symptoms. Study Design Prospective cohort study. Methods Patients referred to Northwestern Medicine Sleep Lab for home sleep testing were enrolled. Patients filled out the Leicester Cough Questionnaire (LCQ) and Reflux Symptom Index (RSI) before completing sleep testing. Home sleep testing results were reviewed, and patients were separated into non‐OSA and OSA groups by standard Apnea‐Hypopnea Index (AHI) criteria. Demographic characteristics and questionnaire scores of the two groups were compared. The relationship between OSA severity, as determined by AHI, and LCQ and RSI scores was assessed. Results Of the 52 patients enrolled, 33 patients met criteria for OSA and 19 patients did not. Comparing patients without OSA versus those with OSA, there was a significant difference in mean LCQ score (129.9 vs. 120.0, respectively; P = .02), implying worse cough symptoms among OSA patients, and mean RSI score (3.2 vs. 11.2, respectively; P = .0013), implying worse upper‐airway reflux symptoms among OSA patients. There was a significant correlation between LCQ score and AHI (r = –0.39, P = .0061) and between RSI score and AHI (r = 0.37, P = .0078). Conclusions OSA patients demonstrate worse chronic cough and LPR‐related quality of life versus non‐OSA patients. Furthermore, the severity of these quality‐of‐life measures was correlated with the severity of the AHI. Chronic cough and particularly the pharyngeal LPR symptoms may be associated with the presence and severity of OSA. Level of Evidence 2 . Laryngoscope, 129:1244–1249, 2019

Objectives/Hypothesis: Otolaryngologic symptoms of obstructive sleep apnea (OSA) and their diagnostic utility are not well studied. We aimed to elucidate the prevalence of otolaryngologic symptoms among patients being evaluated for OSA. Given findings that the Reflux Symptom Index (RSI) was strongly associated with OSA status, we evaluated the diagnostic utility of the RSI for predicting OSA status.

Loss of the desmosomal cell-cell adhesion molecule, Desmoglein 1 (Dsg1), has been reported as an indicator of poor prognosis in head and neck squamous cell carcinomas (HNSCC) overexpressing epidermal growth factor receptor (EGFR). It has been well established that EGFR signaling promotes the formation of invadopodia, actinbased protrusions formed by cancer cells to facilitate invasion and metastasis, by activating pathways leading to actin polymerization and ultimately matrix degradation. We previously showed that Dsg1 downregulates EGFR/Erk signaling by interacting with the ErbB2-binding protein Erbin (ErbB2 Interacting Protein) to promote keratinocyte differentiation. Here, we provide evidence that restoring Dsg1 expression in cells derived from HNSCC suppresses inva-sion by decreasing the number of invadopodia and matrix degradation. Moreover, Dsg1 requires Erbin to downregulate EGFR/Erk signaling and to fully suppress invadopodia formation. Our findings indicate a novel role for Dsg1 in the regulation of invadopodia signaling and provide potential new targets for development of therapies to prevent invadopodia formation and therefore cancer invasion and metastasis.Implications: Our work exposes a new pathway by which a desmosomal cadherin called Dsg1, which is lost early in head and neck cancer progression, suppresses cancer cell invadopodia formation by scaffolding ErbB2 Interacting Protein and consequent attenuation of EGF/Erk signaling.

<p>Supplemental Figure 7: Reduction of Dsg1 mRNA and elevation of Dsg2 mRNA is associated with progression of HNSCC in vivo.</p>