FOXO3 and glioma: WB analysis showed that the total expression level of FOXO3a did not change in glioma cells with SPHK1 overexpressed or knocked down, whereas the phosphorylation level of FOXO3a was significantly increased in SPHK1-transduced glioma cells as compared with vector-control cells, and a dramatic reduction of phosphorylation of FOXO3a was observed in SPHK1 knockdown cells (Figure 5A).