Description
ML-18 is a non-peptide bombesin receptor subtype 3 (BB
3) antagonist that inhibits [
125I]BA1 binding to NCI-H1299 lung cancer cells transfected with human BB
3 receptors (IC
50 = 4.8 μM). It is selective for BB
3 over the gastrin releasing peptide receptor (GRPR) and the neuromedin B receptor (NMBR) with IC
50 values of 16 and >100 μM, respectively, in a radioligand binding assay. ML-18 (16 μM) reversibly inhibits BA1-induced increases in cytosolic calcium in NCI-H1299 cells. It also inhibits BA1-induced phosphorylation of ERK and EGFR and reduces proliferation of NCI-H1299 cells.