Prognostic role of regenerating gene-I in patients with stage-IV head and neck squamous cell carcinoma

Mohamed Aboshanif, Yohei Kawasaki, Yasufumi Omori, Shinsuke Suzuki, Kohei Honda, Satoru Motoyama, Kazuo Ishikawa

Regenerating gene (REG) family is composed of antiapoptotic factors and growth factors that affect epithelial cells within the digestive system. Regenerating gene-I has been studied in different cancers. However, it has never been studied in head and neck cancer. We investigated the expression of REG-I in head and neck SCC and its relevance to patient survival rates. Untreated biopsy specimens of 60 patients with stage IV head and neck SCC were collected, and the expression of REG-I was evaluated using immunohistochemistry. The association between REG-I expression and clinico-pathological features or survival status of the patients was assessed by Chi-square test, Fisher's exact test and Kaplan-Meier method. Cox proportional hazard model was used to identify the independent prognostic factors. Incidence of lymphatic permeation, vascular invasion and pathological lymph nodes was significantly higher in REG-I negative group (p = 0.008, 0.030 and 0.015, respectively). Overall and cancer-free survival rates were significantly higher in REG-I positive group (p = 0.000434 and 1.0847E-8, respectively). Univariate analysis showed that REG-I was an independent prognostic factor for predicting long-term overall survival (p = 0.002), and multivariate analysis showed that REG-I and lymphatic permeation were independent prognostic factors for predicting long-term disease-free survival (p = 0.001 and 0.022, respectively). Our results showed for the first time that, REG-I is expressed in head and neck SCC. REG-I expression is associated with a longer survival status. We conclude that, REG-I might be a prognostic marker in head and neck SSC and should be further investigated.