Peptidergic Systems and Cancer: Focus on Tachykinin and Calcitonin/Calcitonin Gene-Related Peptide Families

SIMPLE SUMMARY: Neurokinins A and B, adrenomedullin, adrenomedullin 2, amylin, and calcitonin gene-related peptide are essential in different tumors. These peptides are involved in tumor cell proliferation and migration, metastasis, angiogenesis, and lymphangiogenesis. Accordingly, several antitumor therapeutic strategies, including peptide receptor antagonists, can be developed. This review highlights the essential roles played by both tachykinin and calcitonin/calcitonin gene-related peptide families in cancer progression, which support the application of promising clinical antitumor therapeutic strategies. ABSTRACT: The roles played by the peptides belonging to the tachykinin (neurokinin A and B) and calcitonin/calcitonin gene-related peptide (adrenomedullin, adrenomedullin 2, amylin, and calcitonin gene-related peptide (CGRP)) peptide families in cancer development are reviewed. The structure and dynamics of the neurokinin (NK)-2, NK-3, and CGRP receptors are studied together with the intracellular signaling pathways in which they are involved. These peptides play an important role in many cancers, such as breast cancer, colorectal cancer, glioma, lung cancer, neuroblastoma, oral squamous cell carcinoma, phaeochromocytoma, leukemia, bladder cancer, endometrial cancer, Ewing sarcoma, gastric cancer, liver cancer, melanoma, osteosarcoma, ovarian cancer, pancreatic cancer, prostate cancer, renal carcinoma, and thyroid cancer. These peptides are involved in tumor cell proliferation, migration, metastasis, angiogenesis, and lymphangiogenesis. Several antitumor therapeutic strategies, including peptide receptor antagonists, are discussed. The main research lines to be developed in the future are mentioned.