Comparison of Endoplasmic Reticulum Stress Messenger Ribonucleic Acid Expression Between Chronic Otitis Media With and Without Cholesteatoma

BACKGROUND: We evaluated and compared the role of endoplasmic reticulum stress in chronic otitis media with cholesteatoma and chronic otitis media without cholesteatoma. METHODS: The messenger ribonucleic acid expression of endoplasmic reticulum stress was measured and compared between chronic otitis media with cholesteatoma and chronic otitis media without cholesteatoma according to the presence or absence of bacteria, type of hearing loss, ossicle destruction, and facial canal dehiscence. RESULTS: The expression of immunoglobulin heavy chain-binding protein messenger ribonucleic acid was higher in the chronic otitis media without cholesteatoma group than in the chronic otitis media with cholesteatoma group, and Protein kinase RNA (PKR)-like endoplasmic reticu-lum kinase and activating transcription factor 6 messenger ribonucleic acid expression were higher in the chronic otitis media with cholestea-toma group than in the chronic otitis media without cholesteatoma group. CONCLUSION: Endoplasmic reticulum stress messenger ribonucleic acids were expressed in both chronic otitis media with cholesteatoma and chronic otitis media without cholesteatoma. The levels of expression of endoplasmic reticulum stress messenger ribonucleic acids differed according to clinical features, suggesting that different endoplasmic reticulum stress pathways are involved in the pathophysiology of different types of chronic otitis media.