GTSE1 promotes tumor growth and metastasis by attenuating of KLF4 expression in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is one of the most common malignant tumors and is characterized by a poor prognosis. Although G2- and S -phase expressed-1 (GTSE1) is known to be involved in the progression and metastasis of various cancers, its significance and mechanism in ccRCC remain unknown. In the present study, we found that GTSE1 was overexpressed in ccRCC tissues, especially in metastatic samples. Moreover, high GTSE1 expression was positively correlated with higher pT stage, tumor size, clinical stage, and WHO/ISUP grade and worse prognosis. And GTSE1 expression served as an independent prognostic factor for overall survival (OS). In addition, GTSE1 knockdown inhibited ccRCC cell proliferation, migration, and invasion, and enhanced cell apoptosis in vitro and in vivo. GTSE1 was crucial for epithelial-mesenchymal transition (EMT) in ccRCC. Mechanistically, GTSE1 depletion could upregulate the expression of Kruppel-like factor 4 (KLF4), which acts as a tumor suppressor in ccRCC. Downregulation of KLF4 effectively rescued the inhibitory effect induced by GTSE1 knockdown and reversed the EMT process. Overall, our results revealed that GTSE1 served as an oncogene regulating EMT through KLF4 in ccRCC, and that GTSE1 could also serve as a novel prognostic biomarker and may represent a promising therapeutic target for ccRCC. GTSE1 performs oncogenic functions in various tumors; however, its role in clear cell renal cell carcinoma (ccRCC) remains unknown. Here, the authors found that GTSE1 is overexpressed in ccRCC, and its high expression was positively relation with advanced clinical stages and worse prognosis. In additional, GTSE1 knockdown inhibited ccRCC cell malignant phenotype in vitro and vivo. Mechanistically, GTSE1 promotes ccRCC malignance progression by attenuating KLF4 expression.