title: Bombesin related peptides/receptors and their promising therapeutic roles in cancer imaging, targeting and treatment.
abstract: BACKGROUND
  Despite remarkable advances in tumor treatment, many patients still die from common tumors (breast, prostate, lung, CNS, colon, and pancreas), and thus, new approaches are needed. Many of these tumors synthesize bombesin (Bn)-related peptides and over-express their receptors (BnRs), hence functioning as autocrine-growth-factors. Recent studies support the conclusion that Bn-peptides/BnRs are well-positioned for numerous novel antitumor treatments, including interrupting autocrine-growth and the use of over-expressed receptors for imaging and targeting cytotoxic-compounds, either by direct-coupling or combined with nanoparticle-technology.
  
  
  METHODS
  The unique ability of common neoplasms to synthesize, secrete, and show a growth/proliferative/differentiating response due to BnR over-expression, is reviewed, both in general and with regard to the most frequently investigated neoplasms (breast, prostate, lung, and CNS). Particular attention is paid to advances in the recent years. Also considered are the possible therapeutic approaches to the growth/differentiation effect of Bn-peptides, as well as the therapeutic implication of the frequent BnR over-expression for tumor-imaging and/or targeted-delivery.
  
  
  CONCLUSIONS
  Given that Bn-related-peptides/BnRs are so frequently ectopically-expressed by common tumors, which are often malignant and become refractory to conventional treatments, therapeutic interventions using novel approaches to Bn-peptides and receptors are being explored. Of particular interest is the potential of reproducing with BnRs in common tumors the recent success of utilizing overexpression of somatostatin-receptors by neuroendocrine-tumors to provide the most sensitive imaging methods and targeted delivery of cytotoxic-compounds.
authors.affiliation: a Digestive Diseases Branch, Cell Biology Section, NIDDK , National Institutes of Health , Bethesda , MD , USA.
authors.forename: Paola
authors.initials: P
authors.lastname: Moreno
authors.affiliation: a Digestive Diseases Branch, Cell Biology Section, NIDDK , National Institutes of Health , Bethesda , MD , USA.
authors.forename: Irene
authors.initials: I
authors.lastname: Ramos-Álvarez
authors.affiliation: b Center for Cancer Research, Office of the Director , NCI, National Institutes of Health , Bethesda , MD , USA.
authors.forename: Terry W
authors.initials: TW
authors.lastname: Moody
authors.affiliation: a Digestive Diseases Branch, Cell Biology Section, NIDDK , National Institutes of Health , Bethesda , MD , USA.
authors.forename: Robert T
authors.initials: RT
authors.lastname: Jensen
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000494:pharmacology; D001839:Bombesin / Q000378:metabolism*; D015195:Drug Design; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D058990:Molecular Targeted Therapy; D053758:Nanoparticles; D009369:Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology; D018004:Receptors, Bombesin / Q000378:metabolism*
chemical_list: D000970:Antineoplastic Agents; D018004:Receptors, Bombesin; D001839:Bombesin
keywords: Bombesin; CNS tumor; breast cancer; cancer; gastrin-releasing peptide; lung cancer; nanoparticles; prostate cancer; targeted therapy