The roles of toll-like receptors in carcinogenesis and cancer immunotherapy

Toll-like receptors (TLRs) are probably the most important class of pattern-recognition receptors. Members of the TLR family play key roles in the both innate and adaptive immune responses. Recognition of pathogen-associated molecular patterns (PAMPs) by TLRs, either alone or in heterodimerization with other TLR or non-TLR receptors, induces the production of signals that are responsible for the activation of genes important for an effective host defense, especially those of proinflammatory cytokines. Thus, TLRs are involved in the development of many pathological conditions including infectious diseases, tissue damage, and cancer especially. In this review, the contribution of TLRs to tumorgenesis is evaluated. We hope to provide new insight into the progression of cancer and more importantly into the potential for TLRs as targets of therapeutics.