ZSTK474 is a potent inhibitor of all four isoforms of class I PI 3-kinase (α 6.7 nM β 10.4 nM γ 11.7 nM δ 1.8 nM). It binds to the ATP-binding pocket and is more active and less toxic than LY294002. ZSTK474 shows anti-tumor activity against human xenografts (A549 PC-3 WiDr) in mice by arresting cell growth. In addition it was able to inhibit osteoclast formation and collagen-induced arthritis in a mouse model.
