Moreover, real-time recorded images of the tube formation assay (Figure 3G) showed that conditioned medium (CdM) from GBE1 knockdown glioma cells made HUVECs form fewer tubules compared with the negative control, indicating that GBE1 knockdown impaired the ability of glioma cells to promote angiogenesis (Figure 3H). This evidence concerns the gene GBE1 and central nervous system cancer.