TLR9 and neoplasm: In contrast, TLR9 as well as TLR7 have initially been described to exert tumor‐promoting roles in pancreatic cancer: TLR9 ligation was demonstrated to induce pancreatic stellate cells (PSCs) to become fibrogenic and secrete chemokines that promote epithelial cell proliferation,20 and stimulation of TLR7 was shown to lead to an acceleration of tumor progression, while its inhibition attenuated cancer cell growth in vitro as well as in mouse models.21