PDCD4 and glioblastoma: Cell lines of grade IV glioblastoma multiforme exhibit higher FAT1 expression than grade III glioma cell lines; in addition, FAT1 knockdown in grade IV cell lines reduces cell migration and invasion and increases the expression of programmed cell death 4, a known tumor-suppressor; moreover, the migration and invasion of glioma cells are restored in FAT1-deficient cells by the simultaneous knockdown of programmed cell death 4 [29].