Peptides such as substance P (a full review focused on its participation in cancer was recently published [5]), neurotensin, orexin, angiotensin II, neuropeptide Y, vasoactive intestinal peptide, calcitonin gene-related peptide, adrenomedullin, adrenomedullin 2 or intermedin, and amylin contribute to cancer development [1,2,6]. Here, TAC1 is linked to cancer.