Neuroendocrine Tumors Express PAC1 Receptors

: Neuroendocrine tumors (NETs) of the gastrointestinal tract can be grossly divided into two general types: carcinoid and pancreatic endocrine tumors. The former develop in the luminal intestine whereas the latter occur within the pancreas. To ascertain whether pituitary adenylate cyclase‐activating polypeptide (PACAP) has a biological effect on the regulation of secretion or growth, we studied the well‐established NET cell line, BON. BON cells have been shown previously to contain chromogranin A, neurotensin, and serotonin. In response to mechanical stimulation, BON cells have been demonstrated to release serotonin. The current article demonstrates that the high‐affinity PAC1 receptor is expressed on the NET cell line BON. These results indicate that PACAP may regulate the biological release of peptides and serotonin from BON cells and that, like in solid tumors, PACAP could potentially stimulate the growth of BON cells.