TLR9 and cancer: Indeed, different TLRs ligands can lead to either proliferation (TLR2, TLR4, TLR9; Tarnani et al., 2010), apoptosis (TLR3 and TLR9; Liang et al., 2010), or chemoresistance (TLR7 and TLR8; Cherfils-Vicini et al., 2010) of different cancer cells (Rakoff-Nahoum and Medzhitov, 2009).