PI3K/AKT pathways mediate AMP-18-induced phosphorylation of p21.

<p>Cells were untreated (Con); treated with rhAMP-18 (2 μg/mL), PI3K inhibitor (Inh) (LY294002, 10 μM), AKT inhibitor (VIII, 2 μM) alone, or a combination of AMP-18 with either of the inhibitors (<i>Panel</i><b>A</b>); or treated with TNF-α (50 ng/mL), AMP-18 alone, or TNF-α and AMP-18 in the presence or absence of PI3K inhibitor (<i>Panel</i><b>B</b>); or AKT inhibitor (<i>Panel</i><b>C</b>). When cells were exposed to multiple agents, they were pre-treated with either inhibitor for 30 min, followed by treatment with rhAMP-18 for 30 min before final exposure to TNF-α for 2 h. Phosphorylation of p21 was determined by immunoblotting with a phospho-p21 antibody, and equal loading was verified by immunoblotting of actin. Representative results from 3 independent experiments are shown.