TLR7 and TLR8, resiquimod, and 852A

Abstract

The Toll-like receptors 7 and 8 as integral component of the host innate immune system are endosomally-located receptors that sense single-stranded RNAs derived from microbes or damaged cells. Engagement of these receptors triggers the host inflammatory response to eliminate and clear invading microbes or dead tissues. Harnessing the protective function of these receptors in immune cells has proven to be successful in treatment of superficial bladder and skin cancers. However, preclinical evidence suggests that aberrant activation of these TLRs in cancer cells or tumor-supporting cells can potentially accelerate cancer growth. Therefore, much work is needed to clearly delineate the role of these TLRs in different cancer, as well as each different cell-types in the tumor microenvironment, to develop a therapeutic strategies that have the highest chance of success in clinical trials.