GLIPR1 and central nervous system cancer: We next examined the effects of RTVP-1 on glioma cell spreading and the role of N-WASP in this process and found that overexpression of RTVP-1 in the A172 cells enhanced cell spreading (Figure 3A), whereas silencing of RTVP-1 in the U87 cells inhibited this process (Figure 3B).