PD 168368 is a competitive antagonist of neuromedin B (NMB) receptors (Kis = 15-45 nM for rat and human receptors expressed in various cell lines). It blocks the elevation of intracellular calcium and release of inositol phosphate induced by NMB in cells expressing NMB receptors. PD 168368 is selective for NMB receptors over those for related peptide agonists, including bombesin and gastrin-releasing peptide. It is also an agonist of formyl-peptide receptors (FPRs) at higher concentrations (EC50s = 0.57 and 0.24 μM for FPR1 and FPR2, respectively). PD 168368 induces cell cycle arrest and apoptosis in MDA-MB-231 breast cancer cells and blocks neovascularization and cancer cell growth in breast cancer xenograft tumors in mice.
![(S)-α-Methyl-α-[[[(4-nitrophenyl)amino]carbonyl]amino]-N-[[1-(2-pyridinyl)cyclohexyl]methyl]-1H-indole-3-propanamide](https://www.chemicalbook.com/CAS/GIF/204066-82-0.gif)
