In previous studies, various other of our cytotoxic conjugates, such as cytotoxic analog of LH-RH (AN-207), somatostatin (AN-238) and bombesin (AN-215), powerfully inhibited growth in nude mice of human pancreatic cancer lines that expressed the specific receptors for those carrier peptides (17, 18). Here, GNRH1 is linked to familial pancreatic carcinoma.