Identification of glia maturation factor beta as an independent prognostic predictor for serous ovarian cancer

Serous ovarian carcinoma (SOC) is the most common subtype of epithelial ovarian cancer which remains the leading cause of death from gynaecologic malignancy. Further knowledge of the proteins involved in serous ovarian cancer may lead to new treatment targets, new markers for early detection or prognosis prediction. In this study, we applied proteomic techniques to analyse the protein expression profiles of SOC and normal ovarian epithelium tissues. Totally 54 aberrantly expressed proteins were identified using 2-DE combined with MALDI-TOF/TOF. Six of these proteins were validated by western blot. Corresponding gene expression analysis of these proteins was also performed using real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR). Additionally, we analysed glia maturation factor beta (GMFB) protein expression by immunohistochemistry in 246 patients with various degrees of ovarian epithelial lesions. GMFB expression in SOC was found to be significantly enhanced than that in normal epithelium, benign serous adenoma and borderline serous adenoma tissues, and was positively correlated with FIGO stage (P = 0.012). High GMFB expression was associated with poor disease-free survival (P = 0.010) and overall survival (P = 0.003), while multivariate analysis revealed GMFB to be an independent prognostic factor for disease-free survival (P = 0.026) and overall survival (P = 0.006) in patients with SOC. We therefore propose that proteins identified here may be involved in the development or progression of SOC, and GMFB can be considered as a prognostic predictor for SOC patients.