TLR9 and neoplasm: CpG-oligonucleotides (CpG-ODNs) are another form of immunotherapy that works by mimicking bacterial DNA, targeting the Toll-Like Receptor-9 (TLR9), and triggering an immune response through T cells, NK cells, B cells, macrophages, dendritic cells, and cytokine release in the host that can simultaneously attack tumor cells (199).