To have generally accepted view, we are currently investigating the value of in-vivo targeting 5-HT1B and 5-HT1D receptors in nude mice-bearing PANC-1 tumor xenografts using siRNA-nanoparticles, to demonstrate the role of these receptors in pancreatic tumor progression, in order to establish a novel and efficient molecularly targeted therapy for pancreatic cancer. This evidence concerns the gene HTR1B and neoplasm.