Overall, this evidence supports a general association of CD73-mediated formation of extracellular adenosine with the activation of A2AR, although an association of CD73 activity with A2BR has been described in some tissues/cells where A2BR-mediated responses are predominant, such as osteoblasts [62], dendritic cells [63] or glioblastoma cells [64]. This evidence concerns the gene NT5E and glioblastoma.