FTI FPT III blocks phosphorylation of ERK1,2.

INA-6 cells were cultivated with 2 ng/mL IL-6 (lanes 1-4) or with BMSCs (lanes 5-8). The IL-6–independent cell lines U266 (lanes 9-12) and Namalwa (lane 13) were cultivated without IL-6 or BMSCs. U266 (lanes 10-12) and INA-6 (lane 2-4 and 6-8) cells were treated with FPT III for 12 hours. Western blot analysis with a Thr202/Tyr204-phosphospecific anti-ERK1,2 antibody was performed to analyze phosphorylation of ERK1,2 (pERK1,2) in INA-6, U266, and Namalwa cells. Western blot analysis of the unphosphorylated ERK1,2 indicates equal loading.