TLR7 and cancer: The synergistic roles of MEK1/2 inhibitor, when combined with TLR7 agonist, may be explained by: (i) subversion of the immunosuppressive roles of IL-10 signaling, (ii) regulatory roles of IRF1 in cellular metabolism, and (iii) IRF1-mediated gene expression of macrophage M1 markers such as TNF-α, a potent anti-cancer cytokine (53).