Furthermore, a notable increase of Akt phosphorylation is induced by PRAS40 overexpression in Ewing sarcoma family tumor (ESFT) cells [22], whereas a significant decrease of Akt phosphorylation with PRAS40 knockdown has been found in ESFT cells, liver cancer cells, skeletal muscle cells and fibroblasts [22, 34, 44, 45]. Here, AKT1S1 is linked to Ewing sarcoma/peripheral primitive neuroectodermal tumor.