Other TLRs (TLR3, TLR7, TLR8, TLR9) are localized within cell and sense viral RNA and CpG DNA.[21] In addition to PAMP ligands, an increasing number of DAMPs are reported to associate with TLRs in cancer cells.[22] Kim et al found that the endogenous versican, an extracellular matrix proteoglycan, induced inflammatory tumor microenvironment and stimulated metastasis of Lewis lung carcinoma through activation of TLR2–TLR6 complex.[23] Endogenous heat-shock proteins (HSPs) are accumulated in tumor cells, and a fraction of HSPs can be released into the extracellular milieu from tumor cells. This evidence concerns the gene TLR9 and cancer.