Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Mol Cancer Ther ; 19(10): 1970-1980, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32788207

RESUMEN

The deubiquitinase USP7 regulates the levels of multiple proteins with roles in cancer progression and immune response. Thus, USP7 inhibition may decrease oncogene function, increase tumor suppressor function, and sensitize tumors to DNA-damaging agents. We have discovered a novel chemical series that potently and selectively inhibits USP7 in biochemical and cellular assays. Our inhibitors reduce the viability of multiple TP53 wild-type cell lines, including several hematologic cancer and MYCN-amplified neuroblastoma cell lines, as well as a subset of TP53-mutant cell lines in vitro Our work suggests that USP7 inhibitors upregulate transcription of genes normally silenced by the epigenetic repressor complex, polycomb repressive complex 2 (PRC2), and potentiate the activity of PIM and PI3K inhibitors as well as DNA-damaging agents. Furthermore, oral administration of USP7 inhibitors inhibits MM.1S (multiple myeloma; TP53 wild type) and H526 (small cell lung cancer; TP53 mutant) tumor growth in vivo Our work confirms that USP7 is a promising, pharmacologically tractable target for the treatment of cancer.


Asunto(s)
Peptidasa Específica de Ubiquitina 7/antagonistas & inhibidores , Animales , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Femenino , Humanos , Ratones , Modelos Moleculares
2.
J Med Chem ; 63(10): 5398-5420, 2020 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-32302140

RESUMEN

USP7 is a promising target for cancer therapy as its inhibition is expected to decrease function of oncogenes, increase tumor suppressor function, and enhance immune function. Using a structure-based drug design strategy, a new class of reversible USP7 inhibitors has been identified that is highly potent in biochemical and cellular assays and extremely selective for USP7 over other deubiquitinases. The succinimide was identified as a key potency-driving motif, forming two strong hydrogen bonds to the allosteric pocket of USP7. Redesign of an initial benzofuran-amide scaffold yielded a simplified ether series of inhibitors, utilizing acyclic conformational control to achieve proper amine placement. Further improvements were realized upon replacing the ether-linked amines with carbon-linked morpholines, a modification motivated by free energy perturbation (FEP+) calculations. This led to the discovery of compound 41, a highly potent, selective, and orally bioavailable USP7 inhibitor. In xenograft studies, compound 41 demonstrated tumor growth inhibition in both p53 wildtype and p53 mutant cancer cell lines, demonstrating that USP7 inhibitors can suppress tumor growth through multiple different pathways.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/química , Descubrimiento de Drogas/métodos , Peptidasa Específica de Ubiquitina 7/antagonistas & inhibidores , Peptidasa Específica de Ubiquitina 7/química , Administración Oral , Animales , Línea Celular Tumoral , Cristalografía por Rayos X/métodos , Humanos , Ratones , Ratones Endogámicos NOD , Ratones Desnudos , Ratones SCID , Estructura Terciaria de Proteína , Peptidasa Específica de Ubiquitina 7/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
3.
Mol Cell ; 71(4): 637-648.e5, 2018 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-30118682

RESUMEN

Although macrophages are armed with potent antibacterial functions, Mycobacterium tuberculosis (Mtb) replicates inside these innate immune cells. Determinants of macrophage intrinsic bacterial control, and the Mtb strategies to overcome them, are poorly understood. To further study these processes, we used an affinity tag purification mass spectrometry (AP-MS) approach to identify 187 Mtb-human protein-protein interactions (PPIs) involving 34 secreted Mtb proteins. This interaction map revealed two factors involved in Mtb pathogenesis-the secreted Mtb protein, LpqN, and its binding partner, the human ubiquitin ligase CBL. We discovered that an lpqN Mtb mutant is attenuated in macrophages, but growth is restored when CBL is removed. Conversely, Cbl-/- macrophages are resistant to viral infection, indicating that CBL regulates cell-intrinsic polarization between antibacterial and antiviral immunity. Collectively, these findings illustrate the utility of this Mtb-human PPI map for developing a deeper understanding of the intricate interactions between Mtb and its host.


Asunto(s)
Proteínas Bacterianas/genética , VIH/genética , Interacciones Huésped-Patógeno , Mycobacterium tuberculosis/genética , Proteínas Proto-Oncogénicas c-cbl/genética , Factores de Virulencia/genética , Animales , Proteínas Bacterianas/inmunología , Línea Celular Tumoral , Chlamydia trachomatis/genética , Chlamydia trachomatis/inmunología , Regulación de la Expresión Génica , VIH/inmunología , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/inmunología , Humanos , Linfocitos/microbiología , Linfocitos/virología , Macrófagos/microbiología , Macrófagos/virología , Ratones , Mycobacterium tuberculosis/inmunología , Cultivo Primario de Células , Unión Proteica , Mapeo de Interacción de Proteínas , Proteínas Proto-Oncogénicas c-cbl/deficiencia , Proteínas Proto-Oncogénicas c-cbl/inmunología , Células RAW 264.7 , Transducción de Señal , Factores de Virulencia/inmunología
4.
PLoS One ; 10(12): e0144648, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26659560

RESUMEN

Fatty acid synthase (FASN) catalyzes the de novo synthesis of palmitate, a fatty acid utilized for synthesis of more complex fatty acids, plasma membrane structure, and post-translational palmitoylation of host and viral proteins. We have developed a potent inhibitor of FASN (TVB-3166) that reduces the production of respiratory syncytial virus (RSV) progeny in vitro from infected human lung epithelial cells (A549) and in vivo from mice challenged intranasally with RSV. Addition of TVB-3166 to the culture medium of RSV-infected A549 cells reduces viral spread without inducing cytopathic effects. The antiviral effect of the FASN inhibitor is a direct consequence of reducing de novo palmitate synthesis; similar doses are required for both antiviral activity and inhibition of palmitate production, and the addition of exogenous palmitate to TVB-3166-treated cells restores RSV production. TVB-3166 has minimal effect on RSV entry but significantly reduces viral RNA replication, protein levels, viral particle formation and infectivity of released viral particles. TVB-3166 substantially impacts viral replication, reducing production of infectious progeny 250-fold. In vivo, oral administration of TVB-3166 to RSV-A (Long)-infected BALB/c mice on normal chow, starting either on the day of infection or one day post-infection, reduces RSV lung titers 21-fold and 9-fold respectively. Further, TVB-3166 also inhibits the production of RSV B, human parainfluenza 3 (PIV3), and human rhinovirus 16 (HRV16) progeny from A549, HEp2 and HeLa cells respectively. Thus, inhibition of FASN and palmitate synthesis by TVB-3166 significantly reduces RSV progeny both in vitro and in vivo and has broad-spectrum activity against other respiratory viruses. FASN inhibition may alter the composition of regions of the host cell membrane where RSV assembly or replication occurs, or change the membrane composition of RSV progeny particles, decreasing their infectivity.


Asunto(s)
Antivirales/farmacología , Inhibidores Enzimáticos/farmacología , Acido Graso Sintasa Tipo I/antagonistas & inhibidores , Procesamiento Proteico-Postraduccional , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Virus Sincitiales Respiratorios/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Administración Oral , Animales , Antivirales/síntesis química , Inhibidores Enzimáticos/síntesis química , Acido Graso Sintasa Tipo I/genética , Acido Graso Sintasa Tipo I/metabolismo , Expresión Génica , Células HeLa , Células Hep G2 , Interacciones Huésped-Patógeno , Humanos , Lipoilación/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Ácido Palmítico/antagonistas & inhibidores , Ácido Palmítico/metabolismo , Virus de la Parainfluenza 3 Humana/efectos de los fármacos , Virus de la Parainfluenza 3 Humana/crecimiento & desarrollo , Virus de la Parainfluenza 3 Humana/metabolismo , Mucosa Respiratoria/efectos de los fármacos , Mucosa Respiratoria/enzimología , Mucosa Respiratoria/virología , Infecciones por Virus Sincitial Respiratorio/virología , Virus Sincitiales Respiratorios/crecimiento & desarrollo , Virus Sincitiales Respiratorios/metabolismo , Rhinovirus/efectos de los fármacos , Rhinovirus/crecimiento & desarrollo , Rhinovirus/metabolismo , Proteínas Virales/antagonistas & inhibidores , Proteínas Virales/genética , Proteínas Virales/metabolismo , Virión/efectos de los fármacos , Virión/crecimiento & desarrollo , Virión/metabolismo
5.
Cell Host Microbe ; 7(3): 210-20, 2010 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-20227664

RESUMEN

Mycobacterium tuberculosis uses the ESX-1 secretion system to deliver virulence proteins during infection of host cells. Here we report a mechanism of posttranscriptional control of ESX-1 mediated by MycP1, a M. tuberculosis serine protease. We show that MycP1 is required for ESX-1 secretion but that, unexpectedly, genetic inactivation of MycP1 protease activity increases secretion of ESX-1 substrates. We demonstrate that EspB, an ESX-1 substrate required for secretion, is a target of MycP1 in vitro and in vivo. During macrophage infection, an inactive MycP1 protease mutant causes hyperactivation of ESX-1-stimulated innate signaling pathways. MycP1 is required for growth in mice during acute infection, while loss of its protease activity leads to attenuated virulence during chronic infection. As the key ESX-1 substrates ESAT-6 and CFP-10 are highly immunogenic, fine-tuning of their secretion by MycP1 may balance virulence and immune detection and be essential for successful maintenance of long-term M. tuberculosis infection.


Asunto(s)
Proteínas Bacterianas/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Mycobacterium tuberculosis/metabolismo , Mycobacterium tuberculosis/patogenicidad , Subtilisinas/fisiología , Factores de Virulencia/metabolismo , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/fisiología , Recuento de Colonia Microbiana , Técnicas de Inactivación de Genes , Hígado/microbiología , Pulmón/patología , Macrófagos/microbiología , Ratones , Ratones Endogámicos BALB C , Modelos Biológicos , Procesamiento Proteico-Postraduccional , Bazo/microbiología , Subtilisinas/genética , Análisis de Supervivencia
6.
Proc Natl Acad Sci U S A ; 105(2): 710-5, 2008 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-18180457

RESUMEN

The pathogenic mycobacteria that cause tuberculosis (TB) and TB-like diseases in humans and animals elude sterilizing immunity by residing within an intracellular niche in host macrophages, where they are protected from microbicidal attack. Recent studies have emphasized microbial mechanisms for evasion of host defense; less is known about mycobactericidal mechanisms that remain intact during initial infection. To better understand macrophage mechanisms for restricting mycobacteria growth, we examined Mycobacterium marinum infection of Drosophila S2 cells. Among approximately 1,000 host genes examined by RNAi depletion, the lysosomal enzyme beta-hexosaminidase was identified as an important factor in the control of mycobacterial infection. The importance of beta-hexosaminidase for restricting mycobacterial growth during mammalian infections was confirmed in macrophages from beta-hexosaminidase knockout mice. Beta-hexosaminidase was characterized as a peptidoglycan hydrolase that surprisingly exerts its mycobactericidal effect at the macrophage plasma membrane during mycobacteria-induced secretion of lysosomes. Thus, secretion of lysosomal enzymes is a mycobactericidal mechanism that may have a more general role in host defense.


Asunto(s)
Drosophila/microbiología , Lisosomas/enzimología , Infecciones por Mycobacterium/patología , beta-N-Acetilhexosaminidasas/fisiología , Animales , Línea Celular , Dimerización , Humanos , Macrófagos/metabolismo , Macrófagos/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microscopía de Contraste de Fase , Infecciones por Mycobacterium/enzimología , Interferencia de ARN , beta-N-Acetilhexosaminidasas/química
7.
Plant Physiol ; 136(2): 3080-94; discussion 3001-2, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15466235

RESUMEN

Membrane trafficking is central to construction of the cell plate during plant cytokinesis. Consequently, a detailed understanding of the process depends on the characterization of molecules that function in the formation, transport, targeting, and fusion of membrane vesicles to the developing plate, as well as those that participate in its consolidation and maturation into a fully functional partition. Here we report the initial biochemical and functional characterization of patellin1 (PATL1), a novel cell-plate-associated protein that is related in sequence to proteins involved in membrane trafficking in other eukaryotes. Analysis of the Arabidopsis genome indicated that PATL1 is one of a small family of Arabidopsis proteins, characterized by a variable N-terminal domain followed by two domains found in other membrane-trafficking proteins (Sec14 and Golgi dynamics domains). Results from immunolocalization and biochemical fractionation studies suggested that PATL1 is recruited from the cytoplasm to the expanding and maturing cell plate. In vesicle-binding assays, PATL1 bound to specific phosphoinositides, important regulators of membrane trafficking, with a preference for phosphatidylinositol(5)P, phosphatidylinositol(4,5)P(2), and phosphatidylinositol(3)P. Taken together, these findings suggest a role for PATL1 in membrane-trafficking events associated with cell-plate expansion or maturation and point to the involvement of phosphoinositides in cell-plate biogenesis.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fosfatidilinositoles/metabolismo , Proteínas de Transferencia de Fosfolípidos/metabolismo , Secuencia de Aminoácidos , Proteínas de Arabidopsis/química , Regulación de la Expresión Génica de las Plantas , Microscopía Fluorescente , Datos de Secuencia Molecular , Familia de Multigenes , Proteínas de Transferencia de Fosfolípidos/química , Raíces de Plantas/metabolismo , Unión Proteica , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Nicotiana/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...