Triciribine

Triciribine, also known as API-2, NSC 154020, is a cell-permeable tricyclic nucleoside that inhibits the phosphorylation, activation, and signalling of Akt-1, -2, and -3. Akt-1, -2, and -3 are serine/threonine protein kinases in the phosphatidylinositol 3 (PI3)-kinase signalling pathway that play a critical role in the regulation of cell proliferation and survival. Triciribine induced autophagy, which could be interpreted as a defensive mechanism, because an autophagy inhibitor (chloroquine) increased triciribine-induced apoptosis. In vitro, Triciribine (API-2) significantly inhibits Akt-overexpressing human cancer cell lines growth with 50% inhibition at ~5-10 µM. It also inhibits DNA synthesis and displays antiviral activity against HIV-1 and -2. Combinations of triciribine with classic inhibitors targeting other molecules of the PI3K-AKT-pathway led to synergistic anti-proliferative effects.