ZSTK474 is a potent inhibitor of all four isoforms of class I PI 3-kinase (alpha 6.7 nM, beta 10.4 nM, gamma 11.7 nM, delta 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.
