TLR2 and cancer: So far, only a limited number of TLR agonists have been licensed by the FDA for usage in human cancers, including Bacillus Calmette-Guerin (BCG, TLR2/4 agonist for in situ bladder cancer vaccine), monophosphoryl lipid A (MPLA, TLR2/4 agonist as an immunostimulatory adjuvant of Cervarix), and imiquimod (TLR7 agonist for malignancies) (Table 2) [71,72,73,74,75,76,77,78].