Deubiquitination of TNKS1 Regulates Wnt/β-Catenin to Affect the Expression of USP25 to Promote the Progression of Glioma

Abstract

Objective. To explore the regulatory effect of ubiquitin specific protease 25 (USP25) on glioma cell proliferation, migration, invasion, and its underlying mechanism. Methods. The USP25-overexpressed and USP25-knockdown glioma cells were established on U251 and U87 cells, respectively. Glioma cell proliferation ability was evaluated by CCK-8 assay. Cell apoptosis and cell cycle were determined utilizing flow cytometry. The Transwell assay measured cell invasion with wound healing used for cell migration detection. Western blotting established key protein expression levels in the Wnt/β-catenin pathway. The coimmunoprecipitation was used to check Thankyrase 1 (TNKS1) ubiquitination levels. Results. TNKS1 expression levels were found to be considerably repressed in USP25-knockdown glioma cells and elevated in USP25-overexpressed glioma cells, accompanied by Wnt/β-catenin pathway key protein downregulation and upregulation, respectively. Glioma cell invasion, migration, and proliferation activity were dramatically inhibited in USP25-knockdown glioma cells and promoted in USP25-overexpressed glioma cells. TNKS1 ubiquitination level was knowingly increased in USP25-knockdown glioma cells and reduced in USP25-overexpressed glioma cells, suggesting TNKS1 ubiquitination levels were negatively regulated by USP25. Conclusion. USP25 facilitated glioma cell invasion, migration, and proliferation by regulating Wnt/β-catenin through the deubiquitination on TNKS1.