AKT1 and osteosarcoma: Because Akt3 appears to be predominantly expressed in the brain [24], we used the specific inhibitors to block PI3Kα, PI3Kβ, PI3Kγ, PI3Kδ, Akt1 and Akt2 activity and studies the effects of each isoform of PI3Ks and Akts in osteosarcoma cell migration in this study.