IL6 and neoplasm: Conversely, treatment of male LR/Stat3Δ/Δ mice with anti-IL-6 antibody resulted in significantly increased expression levels of immune markers indicative of M1 macrophage polarization, Th1 differentiation and/or cytotoxic (CD8 T/NK cell) anti-tumor response (Ifng, Tbx21, and Gzmb) (Fig. 5c).