AKT1 and renal carcinoma: Our results using constitutively active Gag Akt to prevent the inhibitory action of miR-21 Sponge on DNA synthesis, proliferation and migration of ACHN and Caki-2 cells demonstrate directly the requirement of PIP3 phosphatase activity of PTEN for these biological functions in renal cancer cells (Fig. 6 and Figs. S12, S14).