TNFα Mediated IL-6 Secretion Is Regulated by JAK/STAT Pathway but Not by MEK Phosphorylation and AKT Phosphorylation in U266 Multiple Myeloma Cells
Figure 4
IL-6 secretion by TNFα regulated by JAK/STAT pathway. U266 cells were serum starved for 8 h and treated with indicated JAK/STAT inhibitors for 1 h or transfected with TNFR siRNA. The cells were then stimulated with TNFα to induce IL-6 secretion and harvested for immunoblotting with indicated antibodies (a). Cell supernatants were collected to determine IL-6 levels using ELISA kit (b). TNF receptor targeted siRNA was used as a positive control. Data shown are the means ± SEM of three independent experiments. c: control; 1: TNFα only; 2: TNFα plus 20 M AG490; 3: TNFα plus 10 M JAK inhibitor I; 4: TNFα plus 10 M JAK inhibitor II; 5: TNFα plus TNFR siRNA.
