Recently, we found that Y1R ligands, such as [Pro30, Nle31, Bpa32, Leu34]-NPY(28–36) and [Asn6, Pro34]-NPY, play important roles in tumor-targeted imaging and therapy with high selectivity to breast tumors and less effect on other organs [39, 42, 43]. The gene discussed is NPY; the disease is breast neoplasm.