TLR7 and cancer: Although the earlier studies (Ilyinskii et al., 2014; Alexis et al., 2016) demonstrated an effective local immune activation and an excellent safety profile (that attenuates the level of serum inflammatory cytokines for 50- to 200-folds compared with free R848 administration), up until now the prophylactic use of a TLR7/8 agonist-based nanovaccine for cancer prevention in animal models has not been rigorously evaluated.