TLR9 and neoplasm: In this study, vaccination with antigen plus TLR-9 ligand induced Treg reprograming into polyfunctional T-helper-like cells, producing a wide array of cytokines including IL-2, TNF-α, and IL-17, and expressing cell-surface CD40L, thus providing efficient T cell help for tumor-antigen cross-presentation and development of anti-tumor response (152).