Objective: DEPDC1B, which encodes DEP domain-containing protein 1B, exerts pathogenic effects in diverse cancers, but no such effect has been reported in the case of lower-grade glioma (LGG). Therefore, we sought to investigate the relationship between DEPDC1B expression and the prognosis of patients with LGG and reveal the underlying molecular mechanism.
Materials and methods: First, RT-qPCR and immunohistochemical staining were used to examine DEPDC1B mRNA and protein expression in LGG. Second, transcriptomic data were collected from The Cancer Genome Atlas and Chinese Glioma Genome Atlas databases to investigate the impact of DEPDC1B expression on LGG patients by using the Kaplan-Meier survival analysis, receiver operating characteristic analysis and Cox models. Third, the effects of DEPDC1B on LGG cell proliferation and migration were revealed using wound-healing and Cell Counting Kit-8 assays and Ki67 immunofluorescence staining. Fourth, the Tumor Immune Estimation Resource database was used to examine how DEPDC1B affects the LGG immune microenvironment, and gene set enrichment analysis was used to uncover the signaling pathways in which DEPDC1B is involved in LGG.
Results: DEPDC1B was significantly upregulated in both LGG cells and tissues, and high expression of DEPDC1B contributed to poor prognosis of LGG patients and represented an independent risk factor for LGG. Moreover, DEPDC1B knockdown reduced the proliferation and migration abilities of LGG cells. Lastly, DEPDC1B was found to be positively associated with multiple immune infiltrates and immune-checkpoint markers.
Conclusions: Our findings indicate for the first time that DEPDC1B is a pathogenic gene in LGG. More importantly, we provide a new biomarker and immunotherapeutic target for improving the diagnosis and treatment of LGG patients.