RESUMEN
Selective blockade of gene expression by designed small molecules is a fundamental challenge at the interface of chemistry, biology, and medicine. Transcription factors have been among the most elusive targets in genetics and drug discovery, but the fields of chemical biology and genetics have evolved to a point where this task can be addressed. Herein we report the design, synthesis, and in vivo efficacy evaluation of a protein domain mimetic targeting the interaction of the p300/CBP coactivator with the transcription factor hypoxia-inducible factor-1α. Our results indicate that disrupting this interaction results in a rapid down-regulation of hypoxia-inducible genes critical for cancer progression. The observed effects were compound-specific and dose-dependent. Gene expression profiling with oligonucleotide microarrays revealed effective inhibition of hypoxia-inducible genes with relatively minimal perturbation of nontargeted signaling pathways. We observed remarkable efficacy of the compound HBS 1 in suppressing tumor growth in the fully established murine xenograft models of renal cell carcinoma of the clear cell type. Our results suggest that rationally designed synthetic mimics of protein subdomains that target the transcription factor-coactivator interfaces represent a unique approach for in vivo modulation of oncogenic signaling and arresting tumor growth.
Asunto(s)
Factor 1 Inducible por Hipoxia/química , Factor 1 Inducible por Hipoxia/metabolismo , Péptidos/farmacología , Transducción de Señal/efectos de los fármacos , Secuencia de Aminoácidos , Animales , Antineoplásicos/farmacología , Hipoxia de la Célula , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Femenino , Perfilación de la Expresión Génica , Células HeLa , Humanos , Factor 1 Inducible por Hipoxia/genética , Ligandos , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Péptidos/química , Unión Proteica/efectos de los fármacos , Multimerización de Proteína , Estabilidad Proteica/efectos de los fármacos , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Elementos de Respuesta/genética , Transcripción Genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Factores de Transcripción p300-CBP/metabolismoAsunto(s)
Peptidomiméticos/química , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Secuencia de Aminoácidos , Dicroismo Circular , Cristalografía por Rayos X , Enlace de Hidrógeno , Datos de Secuencia Molecular , Péptidos/química , Unión Proteica , Estructura Secundaria de Proteína , Proteínas Proto-Oncogénicas c-mdm2/antagonistas & inhibidores , Proteína p53 Supresora de Tumor/antagonistas & inhibidoresRESUMEN
Designed ligands that inhibit hypoxia-inducible gene expression could offer new tools for genomic research and, potentially, drug discovery efforts for the treatment of neovascularization in cancers. We report a stabilized alpha-helix designed to target the binding interface between the C-terminal transactivation domain (C-TAD) of hypoxia-inducible factor 1alpha (HIF-1alpha) and cysteine-histidine rich region (CH1) of transcriptional coactivator CBP/p300. The synthetic helix disrupts the structure and function of this complex, resulting in a rapid downregulation of two hypoxia-inducible genes (VEGF and GLUT1) in cell culture.
Asunto(s)
Disulfuros/farmacología , Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Alcaloides Indólicos/farmacología , Transactivadores/antagonistas & inhibidores , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Células HeLa , Humanos , Enlace de Hidrógeno , Factor 1 Inducible por Hipoxia/química , Factor 1 Inducible por Hipoxia/metabolismo , Estructura Secundaria de Proteína , Transactivadores/química , Transactivadores/metabolismoRESUMEN
Selective blockade of hypoxia-inducible gene expression by designed small molecules would prove valuable in suppressing tumor angiogenesis, metastasis and altered energy metabolism. We report the design, synthesis, and biological evaluation of a dimeric epidithiodiketopiperazine (ETP) small molecule transcriptional antagonist targeting the interaction of the p300/CBP coactivator with the transcription factor HIF-1alpha. Our results indicate that disrupting this interaction results in rapid downregulation of hypoxia-inducible genes critical for cancer progression. The observed effects are compound-specific and dose-dependent. Controlling gene expression with designed small molecules targeting the transcription factor-coactivator interface may represent a new approach for arresting tumor growth.
Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Dicetopiperazinas/farmacología , Disulfuros/farmacología , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Factores de Transcripción p300-CBP/antagonistas & inhibidores , Inhibidores de la Angiogénesis/síntesis química , Inhibidores de la Angiogénesis/química , Inhibidores de la Angiogénesis/toxicidad , Unión Competitiva , Hipoxia de la Célula , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Dicetopiperazinas/síntesis química , Dicetopiperazinas/química , Dicetopiperazinas/toxicidad , Disulfuros/síntesis química , Disulfuros/química , Disulfuros/toxicidad , Relación Dosis-Respuesta a Droga , Expresión Génica/efectos de los fármacos , Perfilación de la Expresión Génica , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Luciferasas/genética , Modelos Moleculares , Estructura Molecular , Neovascularización Patológica/metabolismo , Neovascularización Patológica/prevención & control , Análisis de Secuencia por Matrices de Oligonucleótidos , Unión Proteica , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Factores de Transcripción p300-CBP/metabolismoRESUMEN
Herein we review contemporary synthetic and protein design strategies to stabilize the alpha-helical motif in short peptides and miniature proteins. Advances in organometallic catalyst design, specifically for the olefin metathesis reaction, enable the use of hydrocarbon bridges to either crosslink side chains of specific residues or mimic intramolecular hydrogen bonds with carbon-carbon bonds. The resulting hydrocarbon-stapled and hydrogen bond surrogate alpha-helices provide unique synthetic ligands for targeting biomolecules. In the protein design realm, several classes of miniature proteins that display stable helical domains have been engineered and manipulated with powerful in vitro selection technologies to yield libraries of sequences that retain their helical folds. Rational re-design of these scaffolds provide distinctive reagents for the modulation of protein-protein interactions.