Table of Contents
Definition / general | Essential features | Terminology | Sites | Pathophysiology | Radiology description | Treatment | Board review style question #1 | Board review style question #1Cite this page: Obeng R. Bombesin. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/stainsbombesin.html. Accessed January 19th, 2021.
Definition / general
- Class of secreted neuropeptides (called bombesin related peptides) comprised of gastrin releasing peptide / neuromedin C and neuromedin B
- Stimulates the release of gastrin from G cells, regulates appetite and neuropathic pain, functions in the immune system
- Neuromedin B inhibits thyroid stimulating hormone and is involved in smooth muscle contraction
- Exerts function via G protein coupled receptors (GRPR (BB2) and NMBR (BB1))
Essential features
- Neuropeptides that stimulate the release of gastrin and regulate fear (Behav Brain Res 2007;179:133)
- Neuromedin C / gastrin releasing peptide serves as a chemoattractant, acts on phagocytic cells to stimulate phagocytosis (Neuropeptides 1991;20:217), suppresses appetite, regulates stress (Expert Opin Ther Targets 2016;20:1055)
- Neuromedin B also plays a role in cytokine release, decreases gastric motility (Fed Proc 1979;38:2315) and excites nociceptors (pain receptors, Pain 2003;104:609)
- Secreted by many tumor cells and promotes tumor growth
- Receptors for neuromedin B and gastrin releasing peptide / neuromedin C are overexpressed by, and promote tumor growth in tumors of breast, CNS, colon, head and neck, lung, pancreas and prostate
Terminology
- Neuromedin B, neuromedin C, gastrin releasing peptide, GRP 10
Sites
- Neuromedin B: CNS, gastrointestinal tract, pancreas, adrenal medulla, pituitary gland, adipose tissue, urinary tract, uterus (PLoS One 2016;11:e0151871)
- Neuromedin C: CNS (hippocampus, thalamus, spinal cord, olfactory bulb) and gastrointestinal tract (stomach, duodenum) (PLoS One 2016;11:e0151871)
Pathophysiology
- Produced by many tumor cells, promotes tumor growth by mediating activation of epidermal growth factor receptor and HER2 (Expert Opin Ther Targets 2016;20:1055)
- Gastrin releasing peptide / neuromedin C have been implicated in duodenal ulcers and lung cancer
- Neuromedin B is associated with obesity (Front Neurosci 2013;7:193, J Physiol 2010;588:1393)
- Receptors for neuromedin B and gastrin releasing peptide / neuromedin C are overexpressed in many human tumors including CNS, colon, head and neck, pancreas, lung, breast and prostate (PLoS One 2016;11:e0151871)
Radiology description
- Research is ongoing to image tumors utilizing the overexpression of bombesin related peptide receptors (Expert Opin Ther Targets 2016;20:1055)
Treatment
- Current research is focused on bombesin related peptide receptor antagonists to prevent tumor growth (Expert Opin Ther Targets 2016;20:1055)
- Antagonists to bombesin related peptide receptors also suppress benign prostatic hypertrophy (PNAS 2013;110:2617, Biochem Biophys Res Commun 2001;289:225)
Board review style question #1
- Bombesin-like peptides are a class of neuropeptides whose functions include which of the following?
- Inhibition of gastrin secretion
- Inhibition of thyroid stimulating hormone
- Stimulation of appetite
- Suppression of ADH
Board review style question #1
B. Neuromedin B is highly expressed in pituitary. It functions to regulate the levels of thyroid hormones by inhibiting the release of thyroid stimulating hormone.