By showing that Cx43 up-regulates PTEN, one of the most relevant tumor suppressor genes in gliomas [44, 45], and inhibits PI3K/Akt, an important proliferative pathway that is frequently up-regulated in glioma [46], these results expand our knowledge of the mechanism by which Cx43 suppresses tumor growth (Figure 7). This evidence concerns the gene PTEN and glioma.