RESUMEN
The development of novel antitumor agents that have high efficacy in suppressing tumor growth, have low toxicity to nontumor tissues, and exhibit rapid localization in the targeted tumor sites is an ongoing avenue of research at the interface of chemistry, cancer biology, and pharmacology. Supramolecular metal-based coordination complexes (SCCs) have well-defined shapes and geometries, and upon their internalization, SCCs could affect multiple oncogenic signaling pathways in cells and tissues. We investigated the uptake, intracellular localization, and antitumor activity of two rhomboidal Pt(II)-based SCCs. Laser-scanning confocal microscopy in A549 and HeLa cells was used to determine the uptake and localization of the assemblies within cells and their effect on tumor growth was investigated in mouse s.c. tumor xenograft models. The SCCs are soluble in cell culture media within the entire range of studied concentrations (1 nM-5 µM), are nontoxic, and showed efficacy in reducing the rate of tumor growth in s.c. mouse tumor xenografts. These properties reveal the potential of Pt(II)-based SCCs for future biomedical applications as therapeutic agents.
Asunto(s)
Antineoplásicos , Neoplasias Experimentales/tratamiento farmacológico , Compuestos Organometálicos , Platino (Metal) , Transducción de Señal/efectos de los fármacos , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Células HeLa , Humanos , Ratones , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Compuestos Organometálicos/química , Compuestos Organometálicos/farmacología , Platino (Metal)/química , Platino (Metal)/farmacología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
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/metabolismoRESUMEN
Development of anti-cancer agents with high tumor-targeting specificity and efficacy is critical for modern multidisciplinary cancer research. Monoamine oxidase A (MAOA), a mitochondria-bound enzyme, degrades monoamine neurotransmitters and dietary monoamines. Recent evidence suggests a correlation between increased MAOA expression and prostate cancer (PCa) progression with poor outcomes for patients. MAOA induces epithelial-mesenchymal transition (EMT) and augments hypoxic effects by producing excess reactive oxygen species. Thus, development of MAOA inhibitors which selectively target tumors becomes an important goal in cancer pharmacology. Here we describe the design, synthesis, and in vitro and in vivo evaluation of NMI, a conjugate that combines a near-infrared dye for tumor targeting with the moiety derived from the MAOA inhibitor clorgyline. NMI inhibits MAOA with low micromolar IC50, suppresses PCa cell proliferation and colony formation, and reduces migration and invasion. In mouse PCa xenografts, NMI targets tumors with no detectable accumulation in normal tissues, providing effective reduction of the tumor burden. Analysis of tumor specimens shows reduction in Ki-67(+) and CD31(+) cells, suggesting a decrease of cell proliferation and angiogenesis and an increase in M30(+) cells, indicating increased apoptosis. Gene expression profiles of tumors treated with NMI demonstrate reduced expression of oncogenes FOS, JUN, NFKB, and MYC and cell cycle regulators CCND1, CCNE1, and CDK4/6, along with increases in the levels of tumor suppressor gene TP53, cell cycle inhibitors CDKN1A and CDKN2A, and MAOA-downstream genes that promote EMT, tumor hypoxia, cancer cell migration, and invasion. These data suggest that NMI exerts its effect through tumor-targeted delivery of a MAOA-inactivating group, making NMI a valuable anti-tumor agent.
Asunto(s)
Proliferación Celular/efectos de los fármacos , Colorantes/química , Inhibidores de la Monoaminooxidasa/farmacología , Monoaminooxidasa/efectos de los fármacos , Neoplasias de la Próstata/patología , Animales , Masculino , Ratones , Ratones Desnudos , Espectroscopía Infrarroja CortaRESUMEN
We report in vitro and in vivo evaluation of a newly designed trifunctional theranostic agent for targeting solid tumors. This agent combines a dendritic wedge with high boron content for boron neutron capture therapy or boron MRI, a monomethine cyanine dye for visible-light fluorescent imaging, and an integrin ligand for efficient tumor targeting. We report photophysical properties of the new agent, its cellular uptake and in vitro targeting properties. Using live animal imaging and intravital microscopy (IVM) techniques, we observed a rapid accumulation of the agent and its retention for a prolonged period of time (up to 7 days) in fully established animal models of human melanoma and murine mammary adenocarcinoma. This macromolecular theranostic agent can be used for targeted delivery of high boron load into solid tumors for future applications in boron neutron capture therapy.
Asunto(s)
Dendrímeros/uso terapéutico , Neoplasias/diagnóstico , Neoplasias/terapia , Animales , Transporte Biológico , Línea Celular Tumoral , Supervivencia Celular , Dendrímeros/metabolismo , Dendrímeros/farmacocinética , Humanos , Integrinas/metabolismo , Ligandos , Ratones , Neoplasias/patología , Distribución TisularRESUMEN
Hypoxia is a hallmark of solid tumors, is associated with local invasion, metastatic spread, resistance to chemo- and radiotherapy, and is an independent, negative prognostic factor for a diverse range of malignant neoplasms. The cellular response to hypoxia is primarily mediated by a family of transcription factors, among which hypoxia-inducible factor 1 (HIF1) plays a major role. Under normoxia, the oxygen-sensitive α subunit of HIF1 is rapidly and constitutively degraded but is stabilized and accumulates under hypoxia. Upon nuclear translocation, HIF1 controls the expression of over 100 genes involved in angiogenesis, altered energy metabolism, antiapoptotic, and pro-proliferative mechanisms that promote tumor growth. A designed transcriptional antagonist, dimeric epidithiodiketopiperazine (ETP 2), selectively disrupts the interaction of HIF1α with p300/CBP coactivators and downregulates the expression of hypoxia-inducible genes. ETP 2 was synthesized via a novel homo-oxidative coupling of the aliphatic primary carbons of the dithioacetal precursor. It effectively inhibits HIF1-induced activation of VEGFA, LOX, Glut1, and c-Met genes in a panel of cell lines representing breast and lung cancers. We observed an outstanding antitumor efficacy of both (±)-ETP 2 and meso-ETP 2 in a fully established breast carcinoma model by intravital microscopy. Treatment with either form of ETP 2 (1 mg/kg) resulted in a rapid regression of tumor growth that lasted for up to 14 days. These results suggest that inhibition of HIF1 transcriptional activity by designed dimeric ETPs could offer an innovative approach to cancer therapy with the potential to overcome hypoxia-induced tumor growth and resistance.
Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Mama/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Pulmón/efectos de los fármacos , Piperazinas/uso terapéutico , Factores de Transcripción p300-CBP/metabolismo , Animales , Antineoplásicos/química , Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Dimerización , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Pulmón/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Modelos Moleculares , Piperazinas/química , Mapas de Interacción de Proteínas/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
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
Glioblastoma (GBM) is an aggressive brain tumor which is currently treated with temozolomide (TMZ). Tumors usually become resistant to TMZ and recur; no effective therapy is then available. Monoamine Oxidase A (MAO A) oxidizes monoamine neurotransmitters resulting in reactive oxygen species which cause cancer. This study shows that MAO A expression is increased in human glioma tissues and cell lines. MAO A inhibitors, clorgyline or the near-infrared-dye MHI-148 conjugated to clorgyline (NMI), were cytotoxic for glioma and decreased invasion in vitro. Using the intracranial TMZ-resistant glioma model, clorgyline or NMI alone or in combination with low-dose TMZ reduced tumor growth and increased animal survival. NMI was localized specifically to the tumor. Immunocytochemistry studies showed that the MAO A inhibitor reduced proliferation, microvessel density and invasion, and increased macrophage infiltration. In conclusion, we have identified MAO A inhibitors as potential novel stand-alone drugs or as combination therapy with low dose TMZ for drug-resistant gliomas. NMI can also be used as a non-invasive imaging tool. Thus has a dual function for both therapy and diagnosis.
Asunto(s)
Neoplasias Encefálicas/patología , Resistencia a Antineoplásicos/efectos de los fármacos , Sinergismo Farmacológico , Glioma/patología , Inhibidores de la Monoaminooxidasa/farmacología , Monoaminooxidasa/química , Animales , Antineoplásicos Alquilantes/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/metabolismo , Proliferación Celular/efectos de los fármacos , Dacarbazina/análogos & derivados , Dacarbazina/farmacología , Progresión de la Enfermedad , Glioma/tratamiento farmacológico , Glioma/metabolismo , Humanos , Masculino , Ratones , Ratones Desnudos , Temozolomida , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Designed small molecule inhibitors of hypoxia-inducible gene expression have potential to become new research tools for molecular biology, genetics and serve as leads to new therapeutics. We report design, synthesis evaluation of biological activity, and a preliminary mechanistic study of epipolythiodiketopiperazine (ETP) transcriptional antagonist that targets the interaction between the C-terminal transactivation domain (C-TAD) of hypoxia-inducible factor 1α (HIF-1α) and cysteine-histidine rich region (CH1) of transcriptional coactivator p300/CBP. Our results indicate that in cultured cells synthetic ETP 3 disrupts the structure and function of this complex in a dose-dependent manner, resulting in rapid downregulation of hypoxia-inducible gene expression.