Guanylate-binding Protein 2 Expression Is Associated With Poor Survival and Malignancy in Clear-cell Renal Cell Carcinoma

Background/Aim: Clear-cell renal cell carcinoma (ccRCC) is a common recalcitrant cancer. However, little is known about biomarkers of ccRCC. In the present study, we investigated the role of guanylate-binding protein 2 (GBP2), an interferon-induced GTPase, in ccRCC and its potential as a biomarker of this disease. Materials and Methods: GBP2 expression was analyzed using the Gene Expression Omnibus, The Cancer Genome Atlas, and Human Protein Atlas databases. Univariate and multivariate Cox-regression analyses were used to investigate the prognostic value of GBP2 in ccRCC. In addition, quantitative real-time polymerase chain reactions, western blotting, and immunohistochemistry were performed to confirm the expression of GBP2 in tissues from patients with ccRCC who had undergone radical nephrectomy at the Department of Urology, the First Affiliated Hospital of Chongqing Medical University (Chongqing, P. R. China). Cell-function assays were performed to investigate the effect of GBP2 on Caki-1 human kidney-cancer cells. Results: Bioinformatics and in vitro experiments showed that the expression of GBP2 was up-regulated in ccRCC tissues and cells and was positively correlated with the malignant clinicopathological parameters of the disease. Univariate and multivariate Cox-regression analyses showed that GBP2 expression was an independent risk factor for the prognosis of ccRCC. Cell-function assays showed that GBP2 expression promoted the proliferation, migration, and invasion of Caki1 cells through the WNT/beta-catenin signaling pathway. Conclusion: The present results indicate that GBP2 expression may serve as a prognostic biomarker for ccRCC.