RESUMO
The current predominant therapeutic paradigm is based on maximizing drug-receptor occupancy to achieve clinical benefit. This strategy, however, generally requires excessive drug concentrations to ensure sufficient occupancy, often leading to adverse side effects. Here, we describe major improvements to the proteolysis targeting chimeras (PROTACs) method, a chemical knockdown strategy in which a heterobifunctional molecule recruits a specific protein target to an E3 ubiquitin ligase, resulting in the target's ubiquitination and degradation. These compounds behave catalytically in their ability to induce the ubiquitination of super-stoichiometric quantities of proteins, providing efficacy that is not limited by equilibrium occupancy. We present two PROTACs that are capable of specifically reducing protein levels by >90% at nanomolar concentrations. In addition, mouse studies indicate that they provide broad tissue distribution and knockdown of the targeted protein in tumor xenografts. Together, these data demonstrate a protein knockdown system combining many of the favorable properties of small-molecule agents with the potent protein knockdown of RNAi and CRISPR.
Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Proteínas de Neoplasias/antagonistas & inibidores , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/antagonistas & inibidores , Receptores de Estrogênio/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Sítios de Ligação , Biocatálise , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Células MCF-7 , Camundongos , Modelos Moleculares , Terapia de Alvo Molecular , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Transplante de Neoplasias , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Proteólise , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/genética , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Ubiquitina/genética , Ubiquitina/metabolismo , Ubiquitinação , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Receptor ERRalfa Relacionado ao EstrogênioRESUMO
The synthesis and biological evaluation of novel Tie-2 kinase inhibitors are presented. Based on the pyrrolopyrimidine chemotype, several new series are described, including the benzimidazole series by linking a benzimidazole to the C5-position of the 4-amino-pyrrolopyrimidine core and the ketophenyl series synthesized by incorporating a ketophenyl group to the C5-position. Medicinal chemistry efforts led to potent Tie-2 inhibitors. Compound 15, a ketophenyl pyrrolopyrimidine urea analog with improved physicochemical properties, demonstrated favorable in vitro attributes as well as dose responsive and robust oral tumor growth inhibition in animal models.