ZSTK474 is an ATP-competitive pan-class I PI3K inhibitor with IC₅₀s of 16 nM, 44 nM, 4.6 nM and 49 nM for PΙ3Κα, PI3Kβ, PI3Kδ and PI3Kγ, respectively.

Lineweaver-Burk plot analysis revealed that ZSTK474 inhibits all four PI3K isoforms in an ATP-competitive manner. The K_i values determined for the four PI3K isoforms showed that ZSTK474 inhibited the PI3Kδ isoform most effectively with a K_i of 1.8 nM, whereas the other isoforms are inhibited with 4-10-fold higher K_i values. Therefore, ZSTK474 should be regarded as a pan-PI3K inhibitor. We also determined the IC₅₀ values for inhibiting the four PI3K isoforms with ZSTK474 and LY294002. The IC₅₀ values of ZSTK474 (16, 44, 4.6 and 49 nM for PI3Kα, PI3Kβ, PI3Kδ and PI3Kγ, respectively) are shown to be consistent with the K_i values (6.7, 10.4, 1.8 and 11.7 nM for PI3Kα, PI3Kβ, PI3Kδ and PI3Kγ, respectively), which further supported the idea that ZSTK474 inhibits PI3Kδ most potently. Even at a concentration of 100 µM, ZSTK474 inhibits mTOR activity rather weakly.

西域 has not independently confirmed the accuracy of these methods. They are for reference only.

In mice subjected to MCAO, treatment with ZSTK474 is tested at dosages of 50, 100, 200, and 300 mg/kg. Since the 200 mg/kg dose produces significant improvement and no obvious toxic effects (P<0.01), mice are treated with ZSTK474 at a dose of 200 mg/kg/day daily for three post-MCAO days during the remaining experiments of this study. Neurological function is examined in mice suffered from MCAO followed by 24, 48, and 72 h of reperfusion. In the ZSTK474 group, neurological function scores are significantly better than the control group except the corner test.

西域 has not independently confirmed the accuracy of these methods. They are for reference only.

In mice subjected to MCAO, treatment with ZSTK474 is tested at dosages of 50, 100, 200, and 300 mg/kg. Since the 200 mg/kg dose produces significant improvement and no obvious toxic effects (P<0.01), mice are treated with ZSTK474 at a dose of 200 mg/kg/day daily for three post-MCAO days during the remaining experiments of this study. Neurological function is examined in mice suffered from MCAO followed by 24, 48, and 72 h of reperfusion. In the ZSTK474 group, neurological function scores are significantly better than the control group except the corner test.

西域 has not independently confirmed the accuracy of these methods. They are for reference only.

• . Kong D, et al. ZSTK474 is an ATP-competitive inhibitor of class I phosphatidylinositol 3 kinase isoforms. Cancer Sci, 2007, 98(10), 1638-1642.  [Content Brief]

  . Liu F, et al. Prolonged inhibition of class I PI3K promotes liver cancer stem cell expansion by augmenting SGK3/GSK-3β/β-catenin signalling. J Exp Clin Cancer Res. 2018 Jun 25;37(1):122.  [Content Brief]

  . Wang P, et al. Class I PI3K inhibitor ZSTK474 mediates a shift in microglial/macrophage phenotype and inhibits inflammatory response in mice with cerebral ischemia/reperfusion injury. J Neuroinflammation. 2016 Aug 22;13(1):192.  [Content Brief]