title: Interleukin 35 is an independent prognostic factor and a therapeutic target for nasopharyngeal carcinoma.
abstract: OBJECTIVE
  Interleukin (IL)-35 is composed of two subunits: Epstein-Barr virus-induced gene 3 (EBI3) and IL-12p35. Recently, overexpression of IL-35 has been found in several types of cancers. However, its clinical significance in nasopharyngeal carcinoma is still obscure. We have studied the clinical significance of IL-35 expression and its correlation with outcome of nasopharyngeal carcinoma patients.
  
  
  METHODS
  Interleukin 35 expression was investigated in 80 nasopharyngeal carcinoma cases by immunohistochemistry. Moreover, Fisher's exact test, Kaplan-Meier plots, and Cox proportional hazards regression were utilized to analyse these results.
  
  
  RESULTS
  In the present study, IL-35 is highly expressed in the majority of nasopharyngeal carcinoma samples. EBI3 and p35 immunoreactivity in nasopharyngeal carcinoma samples was 67.5% and 51.3%, respectively. Both EBI3 and p35 expressions were significantly associated with advancement of tumour stage. In addition, EBI3 expression was also correlated with lymph node metastasis. Further analysis showed that EBI3 or p35 staining indicated unfavourable prognosis (p < 0.05). Multivariate analysis suggested EBI3 was an independent prognostic predictor (p < 0.05).
  
  
  CONCLUSIONS
  Our results indicate for the first time that IL-35 is correlated with progression of nasopharyngeal carcinoma. Therefore, IL-35 may be a useful target for the treatment of nasopharyngeal carcinoma.
authors.affiliation: Department of Otolaryngology - Head and Neck Surgery, the third Xiangya Hospital, Central South University, Changsha, 410013, P.R. of China.
authors.forename: Yongquan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Otolaryngology - Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, 410008, P.R. of China.
authors.forename: Hong
authors.initials: H
authors.lastname: Sun
authors.affiliation: Department of Otolaryngology, the Affiliated People's Hospital of Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350004, P.R. of China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wu
authors.affiliation: Department of Anaesthesiology, Xiangya Hospital of Central-South University, Changsha, Hunan 410008, P.R. of China.
authors.forename: Qindong
authors.initials: Q
authors.lastname: Tan
authors.affiliation: Department of Anaesthesiology, Xiangya Hospital of Central-South University, Changsha, Hunan 410008, P.R. of China.
authors.forename: Kai
authors.initials: K
authors.lastname: Xiang
keywords: IL-35; immunohistochemistry; nasopharyngeal carcinoma; prognosis