LY294002 is a cell permeable, selective phosphatidylinositol 3-kinase (P13K) inhibitor that acts as a competitor inhibitor of the ATP binding site of the enzyme. LY294002 inhibits cell proliferation of choroidal melanoma OCM-1 cells. In mESC’s LY294002 prevents self-renewal by inhibiting LIF2. LY294002 does not affect the activities of EGF receptor kinase, MAP kinase, PKC, PI 4-kinase, S6 kinase and c-Src even at 50µl. LY294002 has also been shown to be an inhibitor of casein kinase II.