IL6 and cancer: STAT3 activation can induce cancer-promoting inflammation mediated by nuclear factor-kappa B (NF-κB) and IL-6/GP130/JAK pathways while suppressing NF-κB- and STAT1-mediated Th1 antitumor immune responses by decreasing the expression of antitumor cytokines such as IL-12 and IFN [73,75,76].