Endothelial GPR124 deficiency led to BBB disruption, increased tumor hemorrhage, and decreased survival in a GBM mouse model.61 Interestingly, the proliferation capacity of cultured GBM cells was significantly reduced by both tumor cell-specific overexpression and knockdown of the receptor.62 Transcript levels of GPR124 are not detected in RNA-Seq datasets from the Allen Brain Atlas in normal brain cells (Figure 1B), while it is moderately expressed in patient-derived GBM cell lines (Figure 1A). This evidence concerns the gene ADGRA2 and glioblastoma.