Establishment of an immortalized laryngeal posterior commissure cell line as a tool for reflux research

Abstract

Objectives/Hypothesis: Laryngopharyngeal reflux (LPR) has been implicated as a promoter of laryngeal cancer. Within the larynx, the posterior commissure (PC) is the region that usually comes into direct contact with refluxed materials. Specific laryngeal cell lines useful for in vitro studies are not widely available, and noncancer-derived PC laryngeal cell line has not yet been described. Study Design: Experimental study. Methods: Specimens of squamous epithelium from the PC of the larynx were collected from patients without a history or evidence of laryngeal inflammatory or neoplastic diseases. Harvested tissue was cultured and then immortalized by transduction with human papillomavirus E6/E7-encoding lentivirus. PC primary and transformed cells were characterized by light microscopy and immunohistochemistry. Results: Primary cultures established from PC contained < 5% fibroblasts and displayed normal epithelial cell morphology and cytokeratin expression. These cells survived nine passages in culture. Following lentiviral-mediated immortalization, cells retained normal squamous epithelial morphology and survived > 20 passages in culture. Methods were optimized for culture of PC laryngeal epithelial cells, resulting in 90% success rate of culture. Conclusion: A novel immortalized PC laryngeal epithelial cell line has been established. This cell line provides a unique tool for investigating the mechanism of LPR in the development and progression of laryngeal cancer.