Loss of GFAT1 promotes epithelial-to-mesenchymal transition and predicts unfavorable prognosis in gastric cancer

// Fangfang Duan 1, 2, 3, * , Dongwei Jia 1, 2, * , Junjie Zhao 4, * , Weicheng Wu 1, 2 , Lingqiang Min 4 , Shushu Song 1, 2 , Hao Wu 1, 2 , Lan Wang 1, 2, 3 , Hongshan Wang 4 , Yuanyuan Ruan 1, 2 , Jianxin Gu 1, 2, 3 1 Key Laboratory of Glycoconjugate Research Ministry of Public Health, School of Basic Medical Sciences, Fudan University, Shanghai, P.R. China 2 Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, P.R.China 3 Institutes of Biomedical Sciences, Fudan University, Shanghai, P.R. China 4 Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai, P.R. China * These authors contributed equally to this work Correspondence to: Hongshan Wang, email: hongshanwang@fudan.edu.cn Yuanyuan Ruan, email: yuanyuanruan@fudan.edu.cn Keywords: GFAT1, gastric cancer, epithelial-to-mesenchymal transition, prognostic factor, TGF-β1 Received: January 22, 2016      Accepted: May 08, 2016      Published: May 21, 2016 ABSTRACT Gastric cancer remains the third leading cause of cancer-related mortality worldwide, and invasion and metastasis of gastric cancer represent the major reason for its poor prognosis. Glutamine: fructose-6-phosphate amidotransferase 1 (GFAT1) is the first and rate-limiting enzyme of hexosamine biosynthesis pathway (HBP). Nevertheless, the role of GFAT1 in gastric cancer is little investigated. In this study, we found that the expression of GFAT1 was decreased in gastric cancer. Low expression of GFAT1 was positively associated with vessel invasion, late T stage, lymph node metastasis, distant metastasis, advanced TNM stage and poor prognosis in patients with gastric cancer. Furthermore, in vitro and in vivo studies revealed that down-regulation of GFAT1 promoted epithelial-to-mesenchymal transition (EMT) and invasive activities in gastric cancer cells through inducing the expression of TGF-β1. The GFAT1 expression also significantly correlated with EMT-related factors in gastric cancer patients. Together, these findings indicate that GFAT1 functions as a novel suppressor of EMT and tumor metastasis in gastric cancer.