Figure 1.

AKT inhibition by the NDRG2–PP2A complex. HER2 activates PI3K/AKT signaling. PTEN is a dual protein/lipid phosphatase using phosphatidylinositol, 3,4,5 triphosphate (PIP3), a product of PI3K, as a substrate. An increase in PIP3 recruits AKT to the membrane, which is activated by other PIP3-dependent kinases. NDRG2 acts as a bridge mediating the interaction between PP2A and PTEN, thus the NDRG2–PP2A complex recruits PTEN and triggers its activation. PTEN can inhibit AKT activity by inducing dephosphorylation of PIP3, thereby inhibiting AKT-dependent tumor cell metastasis.