In prostate cancer, overexpression or pharmacological stimulation of TLR9 by synthetic CPG oligodeoxynucleotides (CPG-ODNs) has been shown to induce invasion through the upregulation of proangiogenic and protumorigenic signals, such as MMP9, MMP13, IL-8, and TGF-β, and this can allow for immune evasion by the tumor [21,22,23,24,25]. Here, TLR9 is linked to prostate cancer.