BDNF and neoplasm: Interestingly, salivary ACC is capable of producing exosomes promoting a fibroblast-mediated tumor neural invasion due to the expression of promigratory and proinflammatory molecules such as C-X-C motif chemokine ligand 12, neurotrophic receptor tyrosine kinases 1 and 2, neurotrophin 4, NGF, brain-derived neurotrophic factor (BDNF), and C-X-C chemokine receptor type 4 (77).