Tumoral gastrin-releasing peptide (GRP) receptors are potential targets for diagnosis and therapy using radiolabeled or cytotoxic GRP analogs. GRP-receptor overexpression has been detected in endocrine-related cancer cells and, more recently, also in the vascular bed of selected tumors. More information on vascular GRP-receptors in cancer is required to asses their potential for vascular target...

BACKGROUND Peptide receptors, overexpressed in specific cancers, represent new diagnostic and therapeutic targets. In this study, receptors for the gastrin-releasing peptide (GRP), and other members of the bombesin-family of peptides, were evaluated in ovarian neoplasms. METHODS 75 primary, secondary and metastatic ovarian tumors were investigated for their bombesin-receptor subtype expressio...

Exposure of the gastrin-releasing peptide (GRP) receptor to agonists causes a rapid desensitization of the receptor-stimulated mobilization of intracellular calcium. Homologous desensitization occurs by uncoupling the G-proteins from the receptor and by ligand induced internalization. The molecular determinants of desensitization of the GRP receptor are not well known. The importance of tyrosin...

Bombesin-like peptides such as gastrin-releasing peptide (GRP) have been shown to play a role in cancer as autocrine growth factors that stimulate tumor growth through specific receptors. To search for potential clinical indications for GRP analogues, it is important to identify human tumor types expressing sufficient amounts of the respective receptors. In the present study, we have evaluated ...

The ligand-binding properties of the gastrin-releasing peptide (GRP) receptor and the cellular processing of GRP have been studied in the small-cell lung cancer (SCLC) cell line COR-L42. Scatchard analysis of GRP receptor expression indicated a single class of high-affinity receptors (Kd 1.5 nM) and approx. 6700 receptors/cell. GRP bound to its receptor with a Ki of 2.4 nM. The bombesin-related...

introduction: it has been shown that some primary human tumors and their metastases, including prostate and breast tumors, over-express gastrin-releasing peptide (grp) receptors. bombesin is a neuropeptide with a high affinity for these grp receptors. the purpose of this study was to prepare and evaluate the characteristics of a new freeze-dried kit, [6-hydrazinopyridine-3-carboxylic acid (hyni...

The relationship between receptor number and agonist-induced intracellular responses has been well studied in receptors coupled to adenylate cyclase; however, for receptors coupled to phospholipase C (PLC), very little is known about the effect of receptor number on receptor-mediated processes. To explore this issue, we investigated the effect of the number of receptors for gastrin-releasing pe...

The mammalian gastrin-releasing-peptide (GRP) and its structural amphibian analogue, bombesin, are known to be trophic factors for the normal exocrine pancreas. This work investigates the possible role of GRP in the growth of an acinar pancreatic cancer transplanted to the rat and in primary tumor cell cultures. Moreover, this adenocarcinoma was tested for its content of specific bombesin/GRP r...

PURPOSE To determine whether the cytotoxic analogue of bombesin/gastrin-releasing peptide (GRP) AN-215 can inhibit the in vivo growth of four human ovarian cancer cell lines. AN-215 consists of 2-pyrrolinodoxorubicin (AN-201), a superactive derivative of doxorubicin linked to a bombesin antagonist carrier des-D-Tpi-RC-3095. This conjugate binds strongly to receptors for bombesin/GRP and can be ...