RETRACTED: Zhang et al. Shikonin Inhibits the Migration and Invasion of Human Glioblastoma Cells by Targeting Phosphorylated β-Catenin and Phosphorylated PI3K/Akt: A Potential Mechanism for the Anti-Glioma Efficacy of a Traditional Chinese Herbal Medicine. Int. J. Mol. Sci. 2015, 16, 23823–23848. Here, AKT1 is linked to central nervous system cancer.