Figure 1.

Relation of TLRs on immune cells and tumor cells to tumor immunotherapy is depicted. (A) TLRs of immune cells act as sensors in immune surveillance. (B) Sufficient immune cells recognize tumor antigens by TLRs and cause cell destruction through cell lysis, phagocytosis of dying cell, and cytokines secretion. (C) TLRs on tumor cells display different roles in the malignant process. Some TLRs on tumor cells facilitate immune escape, whereas other TLRs could terminate tolerant immune system and induce strong antitumor effects. TLRs = toll-like receptors.