TACR1 and cancer: Non-peptide NK-1R antagonists (e.g., aprepitant (morpholine derivative), L-733,060 (benzyletherpiperidine), L-732,138 (tryptophan-based)) are broad spectrum antitumor compounds that exert an antitumor action against many human cancer cells (e.g., HB, neuroblastoma, glioma, melanoma, retinoblastoma, acute lymphoblastic leukaemia B and T cells, gastric, colon, breast, larynx and pancreatic carcinoma) (Table 1) [4,6].