Phosphatidylinositol 3-
kinase (PI3K) catalyzes the phosphorylation of PI at the three position of the inositol ring to produce the second messengers PtdIns-
(3,4)-
P
2 and PtdIns-
(3,4,5)-
P
3.
1,2,3 PI3Kγ is a class 1B PI3K that is composed of a p110 catalytic subunit and a p101 or p84 regulatory subunit, whereas PI3Kα, β, and δ are class 1A enzymes composed of p110 and p85 subunits.
4 AS-
604850 is a selective, ATP-
competitive inhibitor of PI3Kγ with IC
50 values of 0.25, >20, >20, and 4.5 μM for the human recombinant γ, δ, β, and α isoforms, respectively.
5 AS-
604850 inhibited MCP-
1-
mediated monocyte chemotaxis with an IC
50 value of 21 μM and reduced RANTES-
induced peritoneal neutrophil recruitment in a murine model of leukocyte chemotaxis with an ED
50 value of 42.4 mg/kg.
5