Coley's toxin (a mixture of inactivated Streptococcus pyogenes and Serratia marcescens) and BCG (Bacillus Calmette-Guerin), a TLR2 and TLR4 agonist have been used as a drug for long-term cancer treatment (Galluzzi et al., 2012). Here, TLR4 is linked to cancer.