Neurotransmitters are involved in the progression of different types of cancer and include not only classic neurotransmitters such as catecholamines, serotonin, acetylcholine, glutamate, and histamine but also neuropeptides like substance P, cholecystokinin, neuropeptide γ, calcitonin gene-related peptide, and bradykinin [13,14,15]. This evidence concerns the gene TAC1 and cancer.