Expression levels of proteins involved in cell adhesion and migration (integrin α5, integrin β1, β-catenin, PAN-cadherin, and FAK) were analyzed in U87 glioma cells and compared with the corresponding protein levels in healthy Hs5 cells treated with different graphene flakes (GN and rGO) (Figure 6). This evidence concerns the gene PTK2 and central nervous system cancer.