(A) WT MEFs were pretreated without or with Genistein (40uM) for 30 min followed by treatment without or with TNF for 15 min. Phophorylation of JNK was determined by immunoblotting. (B) WT MEFs were pretreated without or with Piceatannol, followed by treatment with TNF for 15 min. Phosphorylation of JNK was determined. (C) WT MEFs were transfected with control siRNA or Syk siRNA, followed by treatment with TNF for 15 min. Phosphorylation of JNK was determined. (D) WT MEFs were pretreated without or with Piceatannol, followed by treatment with TNF plus CHX for various times. Apoptotic cell death was determined. (E) WT MEFs were transfected with control siRNA or Syk siRNA, followed by treatment with TNF plus CHX for various times. Apoptotic cell death was determined. Results were presented as means ± s.e.m. and represent two independent experiments (D and E). *, P < 0.05 by two-way ANOVA.