bombesin--tyr(4)- and Colorectal-Neoplasms

Human colorectal cancer tissue and matched uninvolved mucosa from 21 patients were examined by radioligand displacement for the presence of binding sites for bombesin-like peptides. Five cancers, but no uninvolved mucosa, expressed high-affinity, low-capacity bombesin binding sites (Kd = 6.53 nM, Bmax = 58.6 fmol mg-1 protein) of the gastrin-releasing peptide (GRP)-preferring subtype (IC50 4.8 nM). Bombesin-like peptides may have a role in the pathogenesis of colorectal cancer, and bombesin receptor antagonists may be of value in the treatment of receptor-positive tumours.

Topics: Aged; Binding Sites; Binding, Competitive; Bombesin; Colon; Colorectal Neoplasms; Female; Gastrin-Releasing Peptide; Humans; Intestinal Mucosa; Iodine Radioisotopes; Kinetics; Male; Middle Aged; Peptides; Radioligand Assay; Receptors, Bombesin; Sensitivity and Specificity