However, U251 and U87 glioma cells has mutated PTEN [41,42] and our results showed that either overexpression or downregulation of NEDD4-1 could affect the migration and invasion of U251 and U87 glioma cells (Figure 1), suggesting that these effect of NEDD4-1 might not be mediated by PTEN. Here, PTEN is linked to glioma.