NPY and neoplasm: Thus, the use of YR antagonists (e.g., Y2R or Y5R antagonists) as broad-spectrum antitumor drugs is a promising anticancer strategy because (1) peptides belonging to the NPY peptide family are involved in the proliferation, migration, and invasion of tumor cells as well as in angiogenesis; (2) tumor cells express YRs, and (3) YR antagonists promote the death of tumor cells.