Human astrocytes, the most abundant cells in the glioma microenvironment, are key players in the healthy brain but also play dynamic roles in pathological conditions [61].Very few functional data on gap-junction (GJ) changes and connexin 43 (in co-culture models of rat astrocytes and GBM cells) have been reported concerning the putative role of astrocytes in supporting GBM proliferation and invasion [61,62]. The gene discussed is GJA1; the disease is central nervous system cancer.