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Updated: Feb 7, 2026

Quantifying Agonist Activity at G Protein-coupled Receptors
Published on: December 26, 2011
Neuropeptide G Protein-Coupled Receptors as Oncotargets
Terry W Moody1, Irene Ramos-Alvarez2, Robert T Jensen2
1Department of Health and Human Services, National Cancer Institute, Center for Cancer Research, National Institute of Diabetes, Digestive, and Kidney Disease (NIDDK), Bethesda, MD, United States.
Abstract:
Neuropeptide G protein-coupled receptors (GPCRs) are overexpressed on numerous cancer cells. In a number of tumors, such as small cell lung cancer (SCLC), bombesin (BB) like peptides and neurotensin (NTS) function as autocrine growth factors whereby they are secreted from tumor cells, bind to cell surface receptors and stimulate growth. BB-drug conjugates and BB receptor antagonists inhibit the growth of a number of cancers. Vasoactive intestinal peptide (VIP) increases the secretion rate of BB-like peptide and NTS from SCLC leading to increased proliferation. In contrast, somatostatin (SST) inhibits the secretion of autocrine growth factors from neuroendocrine tumors (NETs) and decreases proliferation. SST analogs such as radiolabeled octreotide can be used to localize tumors, is therapeutic for certain cancer patients and has been approved for four different indications in the diagnosis/treatment of NETs. The review will focus on how BB, NTS, VIP, and SST receptors can facilitate the early detection and treatment of cancer.
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