Similar to the non-neuronal action of 5-HT, including dedifferentiation of acinar cells and promotion of regeneration after pancreatitis [30], overexpression of 5-HT1B and 5-HT1D receptors stimulates pancreatic cancer progression by promoting proliferation and invasion of PDAC [31]. The gene discussed is HTR1B; the disease is familial pancreatic carcinoma.