Discovery of an SSTR2-Targeting Maytansinoid Conjugate (PEN-221) with Potent Activity in Vitro and in Vivo.
J Med Chem
; 62(5): 2708-2719, 2019 03 14.
Article
em En
| MEDLINE
| ID: mdl-30735385
ABSTRACT
Somatostatin receptor 2 (SSTR2) is frequently overexpressed on several types of solid tumors, including neuroendocrine tumors and small-cell lung cancer. Peptide agonists of SSTR2 are rapidly internalized upon binding to the receptor and linking a toxic payload to an SSTR2 agonist is a potential method to kill SSTR2-expressing tumor cells. Herein, we describe our efforts towards an efficacious SSTR2-targeting cytotoxic conjugate; examination of different SSTR2-targeting ligands, conjugation sites, and payloads led to the discovery of 22 (PEN-221), a conjugate consisting of microtubule-targeting agent DM1 linked to the C-terminal side chain of Tyr3-octreotate. PEN-221 demonstrates in vitro activity which is both potent (IC50 = 10 nM) and receptor-dependent (IC50 shifts 90-fold upon receptor blockade). PEN-221 targets high levels of DM1 to SSTR2-expressing xenograft tumors, which has led to tumor regressions in several SSTR2-expressing xenograft mouse models. The safety and efficacy of PEN-221 is currently under evaluation in human clinical trials.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Receptores de Somatostatina
/
Descoberta de Drogas
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Maitansina
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article