AKT2 and neoplasm: Our xenograft studies suggest that PTEN-deficient melanomas are initially sensitive to AKT2 inhibition but ultimately do not depend on AKT2 over the long term, given our observation of delayed tumor outgrowth in the AKT2 knockdown mice, as well as unmitigated tumor growth of AKT2 KO cells (Supplemental Figure S4C).