Fucosyltransferase 1 (fut1) siRNA inhibits phosphorylated JNK signaling in rheumatoid arthritis (RA) synovial fibroblasts. (A) Western blots were performed to determine whether TNF-α stimulates the phosphorylation of JNK. Phosphorylation of JNK signaling in TNF-α-stimulated fut1 siRNA-transfected RA synovial fibroblasts was significantly decreased at 10 minutes compared to control siRNA-transfected RA synovial fibroblasts. (B) Fut1 siRNA does not inhibit phosphorylation of NFκB, P38, and Erk1/2 in RA synovial fibroblasts. Means are presented with standard errror. *P <0.05 was significant; *p indicates phosphorylated signaling proteins (n = number of RA patient synovial fibroblasts).