IL6 and neoplasm: Additional administration of recombinant IL-6 into B16-F10 tumor-bearing IL-17−/− mice resulted in markedly increased tumor size and p-Stat3 expression, whereas additional recombinant IL-17 administration into B16-F10 tumor-bearing wild-type mice treated with anti-IL-6 mAb did not significantly alter the tumor growth and p-Stat3 expression (Figures 6(d)-6(e)).