Design and in vitro characterization of highly sst2-selective somatostatin antagonists suitable for radiotargeting

Cescato, Renzo; Erchegyi, Judith; Waser, Beatrice; Piccand, Véronique; Maecke, Helmut R; Rivier, Jean E; Reubi, Jean Claude (2008). Design and in vitro characterization of highly sst2-selective somatostatin antagonists suitable for radiotargeting. Journal of medicinal chemistry, 51(13), pp. 4030-7. Easton, Pa.: American Chemical Society 10.1021/jm701618q

Full text not available from this repository. (Request a copy)

Radiolabeled sst 2 and sst 3 antagonists are better candidates for tumor targeting than agonists with comparable binding characteristics (Ginj, M.; Zhang, H.; Waser, B.; Cescato, R.; Wild, D.; Erchegyi, J.; Rivier, J.; Mäcke, H. R.; Reubi, J. C. Proc. Natl. Acad. Sci. U.S.A. 2006, 103, 16436-16441.). Because most of the neuroendocrine tumors express sst 2, we used the known antagonists acetyl- pNO 2Phe (2)- c[ dCys (3)-Tyr (7)- dTrp (8)-Lys (9)-Thr (10)-Cys (14)]- dTyr (15)-NH 2 ( 1) (Bass, R. T.; Buckwalter, B. L.; Patel, B. P.; Pausch, M. H.; Price, L. A.; Strnad, J.; Hadcock, J. R. Mol. Pharmacol. 1996, 50, 709-715. Bass, R. T.; Buckwalter, B. L.; Patel, B. P.; Pausch, M. H.; Price, L. A.; Strnad, J.; Hadcock, J. R. Mol. Pharmacol. 1997, 51, 170; Erratum.) and H-Cpa (2)- c[ dCys (3)-Tyr (7)- dTrp (8)-Lys (9)-Thr (10)-Cys (14)]-2Nal (15)-NH 2 ( 7) (Hocart, S. J.; Jain, R.; Murphy, W. A.; Taylor, J. E.; Coy, D. H. J. Med. Chem. 1999, 42, 1863-1871.) as leads for analogues with increased sst 2 binding affinity and selectivity. Among the 32 analogues reported here, DOTA- pNO 2Phe (2)- c[ dCys (3)-Tyr (7)- dAph (8)(Cbm)-Lys (9)-Thr (10)-Cys (14)- dTyr (15)-NH 2 ( 3) and DOTA-Cpa (2)- c[ dCys (3)-Aph (7)(Hor)- dAph (8)(Cbm)-Lys (9)-Thr (10)-Cys (14)]- dTyr (15)-NH 2 ( 31) had the highest sst 2 binding affinity and selectivity. All of the analogues tested kept their sst 2 antagonistic properties (i.e., did not affect calcium release in vitro and competitively antagonized the agonistic effect of [Tyr (3)]octreotide). Moreover, in an immunofluorescence-based internalization assay, the new analogues prevented sst 2 internalization induced by the sst 2 agonist [Tyr (3)]octreotide without being active by themselves. In conclusion, several analogues (in particular 3, 31, and 32) have outstanding sst 2 binding and functional antagonistic properties and, because of their DOTA moiety, are excellent candidates for in vivo targeting of sst 2-expressing cancers.

Item Type:

Journal Article (Original Article)

Division/Institute:

04 Faculty of Medicine > Service Sector > Institute of Pathology
04 Faculty of Medicine > Service Sector > Institute of Pathology > Tumour Pathology

UniBE Contributor:

Cescato, Renzo; Waser, Beatrice; Piccand, Véronique and Reubi, Jean-Claude

ISSN:

0022-2623

ISBN:

18543899

Publisher:

American Chemical Society

Language:

English

Submitter:

Factscience Import

Date Deposited:

04 Oct 2013 15:02

Last Modified:

04 May 2014 23:19

Publisher DOI:

10.1021/jm701618q

PubMed ID:

18543899

Web of Science ID:

000257391000036

URI:

https://boris.unibe.ch/id/eprint/27073 (FactScience: 101672)

Actions (login required)

Edit item Edit item
Provide Feedback