Subsequently, we performed pathology examination on mouse brain transplanted GSCs using PAS-CD31 double staining and observed that GDEs encapsulating overexpressed circCMTM3 led to the appearance of more VMs in the glioma tissues by in situ tumorigenesis assay, while Stafia-1 significantly reduced VM formation in tumor region (Figure 9E-F). This evidence concerns the gene PECAM1 and central nervous system cancer.