IBU treatment prevents IFNγ-mediated phosphorylation of STAT-1. HepG2 cells were treated with (A) a representative PA derivative (IBU: 6 mM) alone or in combination with TNFα and/or IFNγ. Protein extracts were collected 18 h after treatment. pSTAT 1 (Tyrosine 701), pSTAT-1 (Serine 727), and α-Tubulin protein levels, were detected via western analysis. Representative blots are shown. (B) Densitometry was performed using image J software. a, significantly different from VEH; b, significantly different from TNFα; c, significantly different from Control. Data are represented as mean ± S.E.M of 3 separate experiments. VEH, vehicle; TNF, tumor necrosis factor-alpha, IFN, interferon-gamma; TI, tumor necrosis factor-alpha and interferon-gamma; IBU, ibuprofen; Tyr, tyrosine; Ser, serine.