Significance of REV7 Expression in p16-Negative Oropharyngeal Squamous Cell Carcinoma.

Abstract

REV7 is a multifunctional protein involved in various biological processes, including DNA damage response. REV7 expression in human cancer cells influences sensitivity to DNA-damaging agents, and its high expression level is reportedly associated with a poor prognosis in many carcinomas. However, the significance of REV7 expression in human papillomavirus 16-negative oropharyngeal squamous cell carcinoma (OPSCC) remains unclear. REV7 expression was assessed by immunohistochemical analysis in 79 patients with HPV16-negative OPSCC. We evaluated the effects of inhibiting REV7 expression on the proliferation and cisplatin sensitivity of FaDu, an HPV16-negative pharyngeal SCC cell line. In patients with p16-negative OPSCC, the high-REV7-expression group experienced significantly shorter overall survival than the low-REV7-expression group (p = 0.03) in the Cox regression analysis. Furthermore, REV7-deficient FaDu cells showed suppressed cell growth and enhanced sensitivity to cisplatin in vitro. REV7 expression is associated with a poor prognosis in HPV16-negative OPSCC.