TLR4 and cancer: Consequently, while earlier DC cancer vaccine designs advocated maturation of DCs with a mediator cocktail comprised of TNF-α, PG-E2, IL-1β, and IL-6 [9], more recent strategies for DC based cancer immune therapy utilize TLR agonists in order to trigger IL-12 secretion from the DCs causing differentiation of Th1 and CTL priming human DCs: polyI:C engagement of TLR3 [38], [39], [40]; LPS binding to TLR4 [5], [25], [41], [42], [43], [44]; or synthetic TLR7/8 agonists such as R848 [45], [46].