Deletion of the CaM-binding site of human Grb7, located in the proximal region of its pleckstrin homology domain, had an inhibitory effect on cell attachment to the substrate, impaired the migratory capacity of the cells and the development of brain tumors in vivo shown by implantation of rat glioblastoma cells transfected with a Grb7-mutant lacking the CaM-binding site [288,289]. This evidence concerns the gene GRB7 and glioblastoma.