TLR9 and cancer: Another example is TLR agonists such as CpG-ODN (TLR9 agonist) or R848 (TLR7/8 agonist), which have shown significant therapeutic effects as adjuvants in cancer immunotherapy, enhancing anti-tumor immune responses in various types of cancers, including glioblastoma multiforme and hematological malignancies [39,46,47,58,59,60].