Downregulation of FBP1 Promotes Tumor Metastasis and Indicates Poor Prognosis in Gastric Cancer via Regulating Epithelial-Mesenchymal Transition.

ABSTRACT

BACKGROUND: Recent studies indicated that some glycolytic enzymes are complicated, multifaceted proteins rather than simple components of the glycolytic pathway. FBP1 plays a vital role in glucose metabolism, but its role in gastric cancer tumorigenesis and metastasis has not been fully understood. METHODS: The prognostic value of FBP1 was first studied in The Cancer Genome Atlas (TCGA) database and validated in in-house database. The effect of FBP1 on cell proliferation and metastasis was examined in vitro. Nonparametric test and Log-rank test were used to evaluate the clinical significance of FBP1 expression. RESULTS: In the TCGA cohort, FBP1 mRNA level were shown to be predictive of overall survival in gastric cancer (P = 0.029). In the validation cohort, FBP1 expression were inversely correlated with advanced N stage (P = 0.021) and lymphovascular invasion (P = 0.011). Multivariate Cox regression analysis demonstrated that FBP1 was an independent predictor for both overall survival (P = 0.004) and disease free survival (P<0.001). Functional studies demonstrated that ectopic FBP1 expression inhibited proliferation and invasion in gastric cancer cells, while silencing FBP1 expression had opposite effects (P<0.05). Mechanically, FBP1 serves as a tumor suppressor by inhibiting epithelial-mesenchymal transition (EMT). CONCLUSIONS: Downregulation of FBP1 promotes gastric cancer metastasis by facilitating EMT and acts as a potential prognostic factor and therapeutic target in gastric cancer.