Figure 2

15d-PGJ₂ abrogates JAK phosphorylation in oral SCC cells. (A) 15d-PGJ₂ abrogates IL-6-induced JAK phosphorylation in oral SCC cells. Oral SCC25 cells were treated with NM, or rIL-6 (25 ng ml⁻¹) for 5 or 10 min in the presence or absence of pretreatment with 15d-PGJ₂ (20 μ M) for 30 min, followed by immunoprecipitation for Jak1 and Western blotting for phosphorylated (PY) and total Jak1. For Jak2, cell lysates were blotted with phospho-Jak2 (Y1007, Y1008) antibody and subsequently stripped and reprobed with Jak2 antibody. (B) 15d-PGJ₂ inhibits constitutive JAK phosphorylation in oral SCC cells. Oral SCC9 cells were either untreated or treated with 15d-PGJ₂ (20 μ M) for 5 min, 10 min, 20 min, 30 min and 1 h. (C) Effect of AG490 on constitutive JAK phosphorylation in oral SCC cells. Oral SCC9 cells were either untreated or treated with AG490 (50 μ M) for 5 min, 10 min, 20 min, 30 min and 1 h. In (B) and (C), cell lysates were blotted with phospho-Jak2 (Y1007, Y1008) antibody and subsequently stripped and reprobed with Jak2 antibody.