Upon treatment with miR-203-positive exosomes derived from pancreatic cancer cells, dendritic cells (DCs) downregulate toll-like receptor 4 (TLR4), tumor necrosis factor-α (TNF-α), and interleukin-12 (IL-12) expression [57], which may prevent DC antigen presentation. Here, TLR4 is linked to pancreatic neoplasm.