DBX2 Promotes Glioblastoma Cell Proliferation by Regulating REST Expression

Background: Glioblastoma (GBM) is the most common but lethal brain cancer with poor prognosis. The developing brain homeobox 2 (DBX2) has been reported to play important roles in tumor growth. However, the mechanisms of DBX2 in GBM are still unknown. Objectives: This study aims to investigate the function and mechanisms of DBX2 in GBM. Methods: The expressions of DBX2 and REST in GBM were measured by analyzing data from databases, and the results were checked by qPCR and/or western blot of GBM cell lines. Cell proliferation was determined by CCK8 assay, immunohistochemistry and colony formation assay. ChIP-qPCR was used to determine the binding sites of DBX2 on REST. Results: In this study, we found that the expression of DBX2 was upregulated in the GBM cell lines. The cell proliferation was damaged after blocking DBX2 expression in U87 and U251 GBM cell lines. The expression level of DBX2 had a positive relationship with that of REST. Our ChIPqPCR results showed that DBX2 is directly bound to the promoter region of REST. Additionally, the increased GBM cell proliferation caused by DBX2 overexpression can be rescued by REST loss of function. Conclusion: DBX2 could promote cell proliferation of GBM by binding to the promoter region of REST gene and increasing REST expression.