CPLX2 is a novel tumor suppressor and improves the prognosis in glioma

Abstract Background: Glioma is a type of malignant cancer in the central nervous system. New predictive biomarkers have been investigated in recent years, but the clinical prognosis in glioma remains poor. The function of CPLX2 in glioma and the probable molecular mechanism of tumor suppression was the focus of this investigation. Methods: The glioma transcriptome profile is downloaded from The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) databases were performed to analyze the expression of CPLX2 in glioma. RT-qPCR was performed to detect the expression of CPLX2 in 68 glioma subjects, these patients who have been followed up. Kaplan-Meier survival analyses were done to evaluate the effect of CPLX2 on the prognosis of glioma patients. The CPLX2 knockdown and overexpressed cell lines were constructed to investigate the effect of CPLX2 on glioma. The cell growth, colony formation, and tumor formation in xenograft were performed. Results: The expression of CPLX2 was downregulated in glioma and negatively correlated to the grade of glioma. The higher expression of CPLX2 predicted a longer survival through the analysis of Kaplan-Meier survival curves. Overexpressed CPLX2 impaired tumorigenesis in glioma progression both in vivo and in vitro. Knocking down of CPLX2 promoted the proliferation of the glioma cells. The analysis of GSEA and co-expression analysis revealed that CPLX2 may affect the malignancy of glioma by regulating hypoxia and inflammation pathway. Conclusions: Our data indicated that CPLX2 functioned as a tumor suppressor and could be used as a potential prognostic marker in glioma.