A stimulating (e.g., epinephrine, NE), inhibiting (e.g., dopamine, SM), as well as dual role (stimulating or inhibiting) (e.g., NPY) of Nts and NPs on tumor angiogenesis has been described, which might suggest the role of these molecules in progression and metastasis of tumors (including CRC) [194]. Here, NPY is linked to colorectal carcinoma.