Figure 2. ErbB4 enhances TNF-induced COX-2 expression.

(A) YAMC-ErbB4 cells were exposed to TNF (100 ng/ml) for 3h; COX-2 protein levels were determined by immunoblot analysis. (B) YAMC cells were transfected with non-targeting or ErbB4-specific siRNA pools for 72h. (C) siRNA-transfected cells were stimulated with TNF; whole cell lysates were prepared and subjected to immunoblot analysis for COX-2 induction as well as phosphorylation of the p65 NF-κB subunit as control for active TNF signaling.