NCIt definition : An orally available, s-triazine derivative, ATP-competitive phosphatidylinositol 3-kinase
(PI3K) inhibitor with potential antineoplastic activity. PI3K inhibitor ZSTK474 inhibits
all four PI3K isoforms. Inhibiting the activation of the PI3K/AKT kinase (or protein
kinase B) signaling pathway results in inhibition of tumor cell growth and survival
in susceptible tumor cell populations. Dysregulated PI3K signaling may contribute
to tumor resistance to a variety of antineoplastic agents. This agent does not induce
apoptosis but rather induces strong G(0)/G(1) arrest, which might contribute to its
favorable efficacy in tumor cells.;