GIT1 and neuroblastoma: In this respect, immunohistochemical analyses reveal that RPTPζ and its substrate, GIT1/Cat-1, are co-localized in the processes of pyramidal cells in hippocampus and neocortex in rat brain, and PTN increases tyrosine phosphorylation of GIT1/Cat-1 in neuroblastoma B103 cells (Kawachi et al., 2001).