Prognostic role of Gli1 expression in breast cancer: a meta-analysis

// Bilan Wang 1, 2, 3 , Ting Yu 4 , Yuzhu Hu 4 , Mengmeng Xiang 4 , Haoning Peng 4 , Yunzhu Lin 1, 2, 3 , Lu Han 1, 2, 3 and Lingli Zhang 1, 2, 3 1 Department of Pharmacy, West China Second University Hospital, Sichuan University, Chengdu, 610041, PR China 2 Evidence-Based Pharmacy Center, West China Second University Hospital, Sichuan University, Chengdu, 610041, PR China 3 Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, 610041, PR China 4 Cancer Center, West China Hospital, West China Medical School, Sichuan University and Collaborative Innovation Center, Chengdu, 610041, PR China Correspondence to: Bilan Wang, email: tt173217@163.com Lingli Zhang, email: zhlingli@sina.com Keywords: Gli1, breast cancer, prognosis Received: May 31, 2017      Accepted: June 20, 2017      Published: July 07, 2017 ABSTRACT Glioma-associated oncogene 1 (Gli1) is a critical transcriptional factor of Sonic hedgehog pathway which has been proved to participate in the initiation and progression of tumor in mammalians. However, its clinical value in breast cancer remains unknown. Thus, a meta-analysis was performed to clarify the association of Gli1 over-expression, clinic-pathological characteristics, molecular subtypes and prognosis in breast cancer. According to included criteria, 13 eligible studies containing 2816 patients all around the world were selected in this study. Our results indicated no significant association of Gli1 expression and histological grade (RR = 1.20, 95% CI: [0.98, 1.47]), T stage (RR = 1.05, 95% CI: [0.87, 1.27]), clinical stage (RR = 1.04, 95% CI: [0.93, 1.18]) and lymph node metastasis (RR = 1.12, 95% CI: [0.92, 1.37]). In addition, pooled RR showed no correlation of Gli1 expression and progesterone receptor (PR) (RR = 0.92, 95% CI: [0.70, 1.21]), estrogen receptor (ER) (RR = 1.03, 95% CI: [0.74, 1.42]), human epidermal growth factor receptor 2 (HER-2) (RR = 1.12, 95% CI: [0.90, 1.39]). Nonetheless, up-regulated Gli1 expression predicts shorter disease-free survival (DFS) (HR = 1.38, 95% CI: [1.05, 1.81]), 3-year survival (HR = 1.74, 95% CI: [1.28, 2.36]), 5-year survival (HR = 2.04, 95% CI: [1.62, 2.57]) and overall survival (OS) (HR = 2.05, 95% CI: [1.60, 2.64]). In conclusion, over-expression of Gli1 tends to progressive stages and is related to unfavorable prognosis of breast cancer, which may become a potential prognosis indicator and therapy target in breast cancer.