TLR4 and cancer: Cell surface TLRs, including TLR1, TLR2, TLR4, TLR5, TLR6, and TLR10, can actively capture extracellular information, including tumor cell-released DAMPs or apoptotic cancer cell fragments, such as HMGB1, HSP, and S100, as well as extracellular vesicles containing changed cell components.