Another in vivo study on pancreatic cancer reported that, in DCs, cancer-derived exosomes down-regulate toll-like receptor 4 (TLR4) and downstream tumour necrosis factor-α (TNF-α) and interleukin-12 (IL-12) cytokines via miR-203, thereby decreasing DC expansion [94]. Here, TLR4 is linked to familial pancreatic carcinoma.