RESUMEN
Bcr-Abl transformation leads to chronic myeloid leukemia (CML). The acquirement of T315I mutation causes tyrosine kinase inhibitors (TKI) resistance. This study develops a compound, JMF4073, inhibiting thymidylate (TMP) and cytidylate (CMP) kinases, aiming for a new therapy against TKI-resistant CML. In vitro and in vivo treatment of JMF4073 eliminates WT-Bcr-Abl-32D CML cells. However, T315I-Bcr-Abl-32D cells are less vulnerable to JMF4073. Evidence is presented that ATF4-mediated upregulation of GSH causes T315I-Bcr-Abl-32D cells to be less sensitive to JMF4073. Reducing GSH biosynthesis generates replication stress in T315I-Bcr-Abl-32D cells that require dTTP/dCTP synthesis for survival, thus enabling JMF4073 susceptibility. It further shows that the levels of ATF4 and GSH in several human CML blast-crisis cell lines are inversely correlated with JMF4073 sensitivity, and the combinatory treatment of JMF4073 with GSH reducing agent leads to synthetic lethality in these CML blast-crisis lines. Altogether, the investigation indicates an alternative option in CML therapy.
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Glutatión , Leucemia Mielógena Crónica BCR-ABL Positiva , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Glutatión/metabolismo , Humanos , Animales , Ratones , Inhibidores de Proteínas Quinasas/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Línea Celular Tumoral , Proteínas de Fusión bcr-abl/metabolismo , Proteínas de Fusión bcr-abl/genética , Proteínas de Fusión bcr-abl/antagonistas & inhibidoresRESUMEN
The cell wall is essential for bacteria to maintain structural rigidity and withstand external osmotic pressure. In bacteria, the cell wall is composed of peptidoglycan. Lipid II is the basic unit for constructing highly cross-linked peptidoglycan scaffolds. Transglycosylase (TGase) is the initiating enzyme in peptidoglycan synthesis that catalyzes the ligation of lipid II moieties into repeating GlcNAc-MurNAc polysaccharides, followed by transpeptidation to generate cross-linked structures. In addition to the transglycosylases in the class-A penicillin-binding proteins (aPBPs), SEDS (shape, elongation, division and sporulation) proteins are also present in most bacteria and play vital roles in cell wall renewal, elongation, and division. In this review, we focus on the latest analytical methods including the use of radioactive labeling, gel electrophoresis, mass spectrometry, fluorescence labeling, probing undecaprenyl pyrophosphate, fluorescence anisotropy, ligand-binding-induced tryptophan fluorescence quenching, and surface plasmon resonance to evaluate TGase activity in cell wall formation. This review also covers the discovery of TGase inhibitors as potential antibacterial agents. We hope that this review will give readers a better understanding of the chemistry and basic research for the development of novel antibiotics.
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Bacterias , Peptidoglicano , Peptidoglicano/química , Bacterias/metabolismo , Proteínas de Unión a las Penicilinas , Pared Celular/metabolismo , Proteínas Bacterianas/metabolismoRESUMEN
Dual-targeting anticancer agents 4-29 are designed by combining the structural features of purine-type microtubule-disrupting compounds and HDAC inhibitors. A library of the conjugate compounds connected by appropriate linkers was synthesized and found to possess HDACs inhibitory activity and render microtubule fragmentation by activating katanin, a microtubule-severing protein. Among various zinc-binding groups, hydroxamic acid shows the highest inhibitory activity of Class I HDACs, which was also reconfirmed by three-dimensional quantitative structure-activity relationship (3D-QSAR) pharmacophore prediction. The purine-hydroxamate conjugates exhibit enhanced cytotoxicity against MDA-MB231 breast cancer cells, H1975 lung cancer cells, and various clinical isolated non-small-cell lung cancer cells with different epidermal growth factor receptor (EGFR) status. Pyridyl substituents could be used to replace the C2 and N9 phenyl moieties in the purine-type scaffold, which can help to improve the solubility under physiological conditions, thus increasing cytotoxicity. In mice treated with the purine-hydroxamate conjugates, the tumor growth rate was significantly reduced without causing toxic effects. Our study demonstrates the potential of the dual-targeting purine-hydroxamate compounds for cancer monotherapy.
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Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Animales , Ratones , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Línea Celular Tumoral , Histona Desacetilasas/metabolismo , Antineoplásicos/química , Inhibidores de Histona Desacetilasas/química , Microtúbulos/metabolismo , Purinas/farmacología , Ácidos Hidroxámicos/química , Relación Estructura-Actividad , Proliferación CelularRESUMEN
BACKGROUND: Amyotrophic lateral sclerosis (ALS) associated with TAR DNA-binding protein 43 (TDP-43) aggregation has been considered as a lethal and progressive motor neuron disease. Recent studies have shown that both C-terminal TDP-43 (C-TDP-43) aggregates and oligomers were neurotoxic and pathologic agents in ALS and frontotemporal lobar degeneration (FTLD). However, misfolding protein has long been considered as an undruggable target by applying conventional inhibitors, agonists, or antagonists. To provide this unmet medical need, we aim to degrade these misfolding proteins by designing a series of proteolysis targeting chimeras (PROTACs) against C-TDP-43. METHODS: By applying filter trap assay, western blotting, and microscopy imaging, the degradation efficiency of C-TDP-43 aggregates was studied in Neuro-2a cells overexpressing eGFP-C-TDP-43 or mCherry-C-TDP-43. The cell viability was characterized by alarmarBlue assay. The beneficial and disaggregating effects of TDP-43 PROTAC were examined with the YFP-C-TDP-43 transgenic C. elegans by motility assay and confocal microscopy. The impact of TDP-43 PROTAC on C-TDP-43 oligomeric intermediates was monitored by fluorescence lifetime imaging microscopy and size exclusion chromatography in the Neuro-2a cells co-expressing eGFP-C-TDP-43 and mCherry-C-TDP-43. RESULTS: Four PROTACs with different linker lengths were synthesized and characterized. Among these chimeras, PROTAC 2 decreased C-TDP-43 aggregates and relieved C-TDP-43-induced cytotoxicity in Neuro-2a cells without affecting endogenous TDP-43. We showed that PROTAC 2 bound to C-TDP-43 aggregates and E3 ligase to initiate ubiquitination and proteolytic degradation. By applying advanced microscopy, it was further shown that PROTAC 2 decreased the compactness and population of C-TDP-43 oligomers. In addition to cellular model, PROTAC 2 also improved the motility of transgenic C. elegans by reducing the C-TDP-43 aggregates in the nervous system. CONCLUSIONS: Our study demonstrated the dual-targeting capacity of the newly-designed PROTAC 2 against both C-TDP-43 aggregates and oligomers to reduce their neurotoxicity, which shed light on the potential drug development for ALS as well as other neurodegenerative diseases.
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Esclerosis Amiotrófica Lateral , Enfermedades Neurodegenerativas , Animales , Esclerosis Amiotrófica Lateral/metabolismo , Enfermedades Neurodegenerativas/genética , Proteolisis , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Unión al ADN/metabolismo , Animales Modificados GenéticamenteRESUMEN
To find their potential use in protein research, direct addition of a disulfide compound to alkyne (namely disulfide-yne reaction) and S-arylation with arenediazonium salt (namely disulfide-diazonium reaction) were investigated in aqueous or protic solutions. The reaction of dimethyl disulfide with 5-hexynol performed best under 300 nm irradiation in the presence of sodium acetate to afford 5,6-bis(methylthio)-5-hexenol in 60% yield. Without the prior reduction of a disulfide bond to thiols, the disulfide-yne reactions have the advantage of 100% atom economy. Disulfide-diazonium reaction was triggered by sodium formate and accelerated by photoirradiation with a 450 nm LED lamp (5 W). The reaction of 3,4-dihydroxy-1,2-dithiane with 2-(prop-2-yn-1-yloxy)benzene-1-diazonium tetrafluoroborate (8b) afforded 2-(benzofuran-3-yl)-1,3-dithiepane-5,6-diol (13), confirming that both S substituents originate from the same disulfide molecule. The trastuzumab antibody was incubated with diazonium 8b, followed by α-lytic protease digestion, LC-ESI-MS/MS analysis, and Mascot search, to verify that the proximal C229 and C232 residues on the same heavy chain were reconnected with a (benzofuranyl)methine moiety that originated from 8b, unlike the expected disulfide rebridging across two heavy chains. Nonetheless, disulfide-diazonium reactions still have potential for rebridging disulfide bonds if appropriate proteins and diazonium agents are chosen.
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Disulfuros , Espectrometría de Masas en Tándem , Cromatografía Liquida , Disulfuros/química , Proteínas/química , Compuestos de SulfhidriloRESUMEN
A series of salicylanilide compounds was previously identified as antibacterial agents that inhibit the peptidoglycan formation. To find the exact binding mode, we synthesized a benzophenone-containing salicylanilide compound (1) and used it as a photoaffinity probe to label Acinetobacter baumannii penicillin-binding protein (PBP1b). After incubation and photo-irradiation, the labeled protein was subjected to trypsin digestion, dialysis enrichment, LC-ESI-MS/MS analysis, and Mascot search to reveal an octadecapeptide sequence 364RQLRTEYQESDLTNQGLR381 that was labeled at E372. Our molecular docking experiments suggest a hydrophobic pocket surrounded by R367 and E372 is the binding site of salicylanilide 1. The pocket lies in between the transglycosylase and transpeptidase domains, thus binding of salicylanilide 1 can block the propagation pathway to disrupt the growth of peptidoglycan chain.
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Peptidoglicano Glicosiltransferasa , Benzofenonas/farmacología , Escherichia coli/metabolismo , Simulación del Acoplamiento Molecular , Peptidoglicano , Peptidoglicano Glicosiltransferasa/química , Peptidoglicano Glicosiltransferasa/metabolismo , Etiquetas de Fotoafinidad , Salicilanilidas , Espectrometría de Masas en TándemRESUMEN
Instead of using the lipid II substrate that requires prior labelling with a radioactive isotope or fluorophore to probe the formation of peptidoglycan in bacterial transglycosylation, the released undecaprenyl pyrophosphate (UPP) product is quantitatively measured either using a terpyridine-zinc fluorescence turn-on sensor or simply by the second-order scattering effect of the in situ formed UPP-calcium complex. Both the assay methods are utilized to identify moenomycin A as a potent transglycosylase inhibitor with a consistent IC50 value.
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Bacterias , Peptidoglicano , Pared CelularRESUMEN
A metal nanoparticle composite, namely TPNT1, which contains Au-NP (1 ppm), Ag-NP (5 ppm), ZnO-NP (60 ppm) and ClO2 (42.5 ppm) in aqueous solution was prepared and characterized by spectroscopy, transmission electron microscopy, dynamic light scattering analysis and potentiometric titration. Based on the in vitro cell-based assay, TPNT1 inhibited six major clades of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with effective concentration within the range to be used as food additives. TPNT1 was shown to block viral entry by inhibiting the binding of SARS-CoV-2 spike proteins to the angiotensin-converting enzyme 2 (ACE2) receptor and to interfere with the syncytium formation. In addition, TPNT1 also effectively reduced the cytopathic effects induced by human (H1N1) and avian (H5N1) influenza viruses, including the wild-type and oseltamivir-resistant virus isolates. Together with previously demonstrated efficacy as antimicrobials, TPNT1 can block viral entry and inhibit or prevent viral infection to provide prophylactic effects against both SARS-CoV-2 and opportunistic infections.
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Oro/farmacología , Subtipo H1N1 del Virus de la Influenza A/fisiología , Subtipo H5N1 del Virus de la Influenza A/fisiología , SARS-CoV-2/fisiología , Plata/farmacología , Óxido de Zinc/farmacología , Enzima Convertidora de Angiotensina 2/metabolismo , Antivirales/química , Antivirales/farmacología , Farmacorresistencia Viral/efectos de los fármacos , Aditivos Alimentarios/farmacología , Oro/química , Células HEK293 , Humanos , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Subtipo H5N1 del Virus de la Influenza A/efectos de los fármacos , Nanopartículas del Metal/química , Nanocompuestos/química , Oseltamivir/farmacología , Tamaño de la Partícula , Unión Proteica/efectos de los fármacos , SARS-CoV-2/efectos de los fármacos , Plata/química , Glicoproteína de la Espiga del Coronavirus/metabolismo , Internalización del Virus/efectos de los fármacos , Óxido de Zinc/químicaRESUMEN
Gold nanoparticles (AuNPs) are biocompatible nanomaterials with potential application in the food industry. The safety of AuNPs oral consumption remains inconclusive, and information on possible long-term toxicity is limited. The current study aimed to evaluate the subchronic oral toxicity of AuNPs in male and female Institute of Cancer Research (ICR) mice. Citrate-coated spherical AuNPs with 53 nm diameters were prepared and orally administered to the mice. No mortality or clinical abnormalities were observed following daily administration of AuNPs at the dosages of 0.2, 2, and 20 mg/kg for 90 days. There was no significant difference in body weight or the relative organs' weights between the control and AuNPs-treated mice. No gross abnormalities or histopathological changes were observed except that the male mice treated with high dose (20 mg/kg AuNPs) showed minor infiltration in the kidneys, and female mice showed a reduced A/G ratio and elevated platelet indices. Overall, the 90-day long-term oral consumption of AuNPs did not cause significant toxicity in mice.
RESUMEN
Parkinson's disease (PD) is among the most common neurodegenerative disorders, and its etiology involves both genetic and environmental factors. The leucine-rich repeat kinase (LRRK2) G2019S mutation is the most common genetic cause of familial and sporadic PD. Current treatment is limited to dopaminergic supplementation, as no disease-modifying therapy is available yet. Recent evidence reveals that HMG-CoA reductase (HMGR) inhibitors (statins) exert neuroprotection through anti-neuroinflammatory effects, and histone deacetylase (HDAC) inhibitors mitigate neurodegeneration by promoting the transcription of neuronal survival factors. We designed and synthesized a dual inhibitor, statin hydroxamate JMF3086, that simultaneously inhibits HMGR and HDAC, and examined its neuroprotective effects on LRRK2-G2019S parkinsonism. JMF3086 restored dopaminergic neuron loss in aged LRRK2-G2019S flies and rescued neurite degeneration in primary hippocampal and dopaminergic neurons isolated from transgenic LRRK2-G2019S mice. The molecular mechanisms included downregulation of ERK1/2 phosphorylation, increased anti-apoptotic Akt phosphorylation, and inhibition of GSK3ß activity to maintain cytoskeletal stability in stably transfected LRRK2-G2019S SH-SY5Y human dopaminergic cells. JMF3086 also promoted a-tubulin acetylation and kinesin-1 expression, facilitating antegrade mitochondrial transport in axons. Our findings demonstrate that JMF3086 exerted beneficial effects on restoring LRRK2-G2019S neurite degeneration by maintaining microtubule stability. This dual-target compound may be a promising mechanism-based therapy for PD.
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Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Degeneración Nerviosa/tratamiento farmacológico , Neuritas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Trastornos Parkinsonianos/tratamiento farmacológico , Animales , Drosophila , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Hipocampo/patología , Inhibidores de Histona Desacetilasas/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/genética , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/metabolismo , Ratones , Ratones Transgénicos , Degeneración Nerviosa/metabolismo , Degeneración Nerviosa/patología , Neuritas/metabolismo , Neuritas/patología , Proyección Neuronal/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Fármacos Neuroprotectores/uso terapéutico , Trastornos Parkinsonianos/genética , Trastornos Parkinsonianos/metabolismo , Trastornos Parkinsonianos/patología , Fosforilación/efectos de los fármacosRESUMEN
To develop an effective method for probing O- and N-glycosyltransfer reactions that are accompanied by the release of undecaprenyl pyrophosphate, solanesyl pyrophosphate (SPP) is used as a surrogate to bind a terpyridine zinc complex (Tpy-Zn), forming a fluorescent [Tpy-Zn]-SPP complex (Kass 106,000 M-1 in EtOH-CHCl3) with 5.8 µM LOD in HEPES buffer (10 mM, pH 7.4) containing 10 mM CaCl2 and 0.08% decyl PEG, which is similar to the bioassay conditions for lipid II polymerization.
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Difosfatos , Zinc , LípidosRESUMEN
BACKGROUND: Salmonella enterica serotype Typhimurium is a nontyphoidal and common foodborne pathogen that causes serious threat to humans. There is no licensed vaccine to prevent the nontyphoid bacterial infection caused by S. Typhimurium. METHODS: To develop conjugate vaccines, the bacterial lipid-A free lipopolysaccharide (LFPS) is prepared as the immunogen and used to synthesize the LFPS-linker-protein conjugates 6a-9b. The designed bifunctional linkers 1-5 comprising either an o-phenylenediamine or amine moiety are specifically attached to the exposed 3-deoxy-D-manno-octulosonic acid (Kdo), an α-ketoacid saccharide of LFPS, via condensation reaction or decarboxylative amidation. In addition to bovine serum albumin and ovalbumin, the S. Typhimurium flagellin (FliC) is also used as a self-adjuvanting protein carrier. RESULTS: The synthesized conjugate vaccines are characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and fast performance liquid chromatography (FPLC), and their contents of polysaccharides and protein are determined by phenol-sulfuric acid assay and bicinchoninic acid assay, respectively. Enzyme-linked immunosorbent assay (ELISA) shows that immunization of mouse with the LFPS-linker-protein vaccines at a dosage of 2.5 µg is sufficient to elicit serum immunoglobulin G (IgG) specific to S. Typhimurium lipopolysaccharide (LPS). The straight-chain amide linkers in conjugates 7a-9b do not interfere with the desired immune response. Vaccines 7a and 7b derived from either unfractionated LFPS or the high-mass portion show equal efficacy in induction of IgG antibodies. The challenge experiments are performed by oral gavage of S. Typhimurium pathogen, and vaccine 7c having FliC as the self-adjuvanting protein carrier exhibits a high vaccine efficacy of 74% with 80% mice survival rate at day 28 post the pathogen challenge. CONCLUSIONS: This study demonstrates that lipid-A free lipopolysaccharide prepared from Gram-negative bacteria is an appropriate immunogen, in which the exposed Kdo is connected to bifunctional linkers to form conjugate vaccines. The decarboxylative amidation of Kdo is a novel and useful method to construct a relatively robust and low immunogenic straight-chain amide linkage. The vaccine efficacy is enhanced by using bacterial flagellin as the self-adjuvanting carrier protein.
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Lipopolisacáridos/química , Vacunas contra la Salmonella/química , Vacunas Conjugadas/química , Animales , Lípido A , Ratones , Ratones Endogámicos BALB C , Vacunas contra la Salmonella/inmunología , Vacunas Conjugadas/inmunologíaRESUMEN
This study demonstrates the utilization of a flow chemistry system for continuous glycan hydrolysis and saccharide labeling to assist with the existing methods in glycan structural analysis. Acidic hydrolysis of glycans could be accelerated in a flow system. Aldoses and α-ketoacid-type saccharides were effectively labeled with naphthalene-2,3-diamine (NADA) at 60 °C for 10 min to form the fluorescent naphthimidazole (NAIM) and quinoxalinone (QXO) derivatives, respectively. The NADA-labeled derivatives improved the structural determination and composition analysis for their parent saccharides by using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), liquid chromatography mass spectrometry (LC-MS), and nuclear magnetic resonance (NMR). Furthermore, this protocol was applied to determine the SA-Gal-Glc sequence of GM3-sugar out of six possible permutations.
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Glicómica/métodos , Polisacáridos/metabolismo , Reología , Coloración y Etiquetado , 2-Naftilamina/análogos & derivados , 2-Naftilamina/química , 2-Naftilamina/metabolismo , Glucosa/química , Glucosa/metabolismo , Hidrólisis , Imidazoles/química , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/metabolismo , Polisacáridos/químicaRESUMEN
Antiviral drug resistance in influenza infections has been a major threat to public health. To develop a broad-spectrum inhibitor of influenza to combat the problem of drug resistance, we previously identified the highly conserved E339...R416 salt bridge of the nucleoprotein trimer as a target and compound 1 as an inhibitor disrupting the salt bridge with an EC50 = 2.7 µM against influenza A (A/WSN/1933). We have further modified this compound via a structure-based approach and performed antiviral activity screening to identify compounds 29 and 30 with EC50 values of 110 and 120 nM, respectively, and without measurable host cell cytotoxicity. Compared to the clinically used neuraminidase inhibitors, these two compounds showed better activity profiles against drug-resistant influenza A strains, as well as influenza B, and improved survival of influenza-infected mice.
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Compuestos de Anilina/farmacología , Antivirales/farmacología , Virus de la Influenza A/química , Multimerización de Proteína/efectos de los fármacos , Proteínas de Unión al ARN/metabolismo , Tiazoles/farmacología , Proteínas del Núcleo Viral/metabolismo , Compuestos de Anilina/síntesis química , Compuestos de Anilina/metabolismo , Animales , Antivirales/síntesis química , Antivirales/metabolismo , Sitios de Unión/efectos de los fármacos , Femenino , Ratones Endogámicos BALB C , Simulación del Acoplamiento Molecular , Estructura Molecular , Proteínas de la Nucleocápside , Unión Proteica , Electricidad Estática , Relación Estructura-Actividad , Tiazoles/síntesis química , Tiazoles/metabolismoRESUMEN
Influenza is a long-standing health problem. For treatment of seasonal flu and possible pandemic infections, there is a need to develop new anti-influenza drugs that have good bioavailability against a broad spectrum of influenza viruses, including the resistant strains. Relenza™ (zanamivir), Tamiflu™ (the phosphate salt of oseltamivir), Inavir™ (laninamivir octanoate) and Rapivab™ (peramivir) are four anti-influenza drugs targeting the viral neuraminidases (NAs). However, some problems of these drugs should be resolved, such as oral availability, drug resistance and the induced cytokine storm. Two possible strategies have been applied to tackle these problems by devising congeners and conjugates. In this review, congeners are the related compounds having comparable chemical structures and biological functions, whereas conjugate refers to a compound having two bioactive entities joined by a covalent bond. The rational design of NA inhibitors is based on the mechanism of the enzymatic hydrolysis of the sialic acid (Neu5Ac)-terminated glycoprotein. To improve binding affinity and lipophilicity of the existing NA inhibitors, several methods are utilized, including conversion of carboxylic acid to ester prodrug, conversion of guanidine to acylguanidine, substitution of carboxylic acid with bioisostere, and modification of glycerol side chain. Alternatively, conjugating NA inhibitors with other therapeutic entity provides a synergistic anti-influenza activity; for example, to kill the existing viruses and suppress the cytokines caused by cross-species infection.
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Antivirales/química , Desarrollo de Medicamentos , Virus de la Influenza A/efectos de los fármacos , Gripe Humana/tratamiento farmacológico , Neuraminidasa/antagonistas & inhibidores , Proteínas Virales/antagonistas & inhibidores , Diseño de Fármacos , HumanosRESUMEN
An 8-oxopurine-6-carboxamide compound (1a) was previously identified as an inhibitor of non-small cell lung cancer (NSCLC). In this study, more than 30 purine-6-carboxamide derivatives with variations at the C2, N7, C8, and N9 positions were synthesized to investigate the structure-activity relationship as a basis for the construction of an advanced pharmacophore model. This model suggests that purine-6-hydroxamate and purine-6-amidoxime analogs could form more hydrogen bonds with a target protein to enhance the inhibitory activities against H1975â¯cells. Among the series of analogs, hydroxamate 17 and amidoxime 19a exhibited excellent potency against H1975â¯cells (IC50â¯<â¯1.5⯵M) and other lung cancer cells with either wild-type or mutated epidermal growth factor receptor (EGFR). Mouse experiments indicated that compounds 17 and 19a were efficient anticancer agents with no appreciable toxicity. The mechanisms of action for the induction of cell apoptosis were determined to involve microtubule fragmentation and p53-mediated signaling pathways.
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Amidas/farmacología , Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Ácidos Hidroxámicos/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Oximas/farmacología , Purinas/farmacología , Amidas/química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ácidos Hidroxámicos/química , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Estructura Molecular , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Oximas/química , Purinas/química , Relación Estructura-ActividadRESUMEN
The yeast Candida albicans is the most prevalent opportunistic fungal pathogen in humans. Drug resistance among C. albicans isolates poses a common challenge, and overcoming this resistance represents an unmet need in managing this common pathogen. Here, we investigated CDC8, encoding thymidylate kinase (TMPK), as a potential drug target for the management of C. albicans infections. We found that the region spanning amino acids 106-123, namely the Ca-loop of C. albicans TMPK (CaTMPK), contributes to the hyperactivity of this enzyme compared with the human enzyme (hTMPK) and to the utilization of deoxyuridine monophosphate (dUMP)/deoxy-5-fluorouridine monophosphate (5-FdUMP) as a substrate. Notably, expression of CaTMPK, but not of hTMPK, produced dUTP/5-FdUTP-mediated DNA toxicity in budding yeast (Saccharomyces cerevisiae). CRISPR-mediated deletion of this Ca-loop in C. albicans revealed that the Ca-loop is critical for fungal growth and susceptibility to 5-fluorouridine (5-FUrd). Of note, pathogenic and drug-resistant C. albicans clones were similarly sensitive to 5-FUrd, and we also found that CaTMPK is essential for the growth of C. albicans In conclusion, these findings not only identified a target site for the development of CaTMPK-selective drugs, but also revealed that 5-FUrd may have potential utility as drug for managing C. albicans infections.
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Candida albicans/enzimología , Proteínas Fúngicas/química , Nucleósido-Fosfato Quinasa/química , Pirimidinas/farmacología , Secuencia de Aminoácidos , Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Candida albicans/crecimiento & desarrollo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Edición Génica , Humanos , Cinética , Pruebas de Sensibilidad Microbiana , Nucleósido-Fosfato Quinasa/genética , Nucleósido-Fosfato Quinasa/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Especificidad por Sustrato , Uridina/análogos & derivados , Uridina/farmacología , Uridina Monofosfato/química , Uridina Monofosfato/metabolismoRESUMEN
A Cu(ii)-[di(2-methylpyridyl)methylamino]coumarin fluorescence turn-on sensor (Cu-1b) is designed to detect phosphate ions with Kass = 1.4 × 105 M-1 in HEPES buffer. Cu-1b is applied to probe the GlgE-catalyzed maltose-transfer reaction of α-maltose-1-phosphate to α-1,4-glucan with concomitant release of phosphate ions in Mycobacterium tuberculosis.
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Aminas/química , Cobre/química , Cumarinas/química , Pruebas de Enzimas/métodos , Glucosiltransferasas/metabolismo , Compuestos Organometálicos/química , Ácidos Picolínicos/química , Biocatálisis , DimerizaciónRESUMEN
Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) is a major advance in treating NSCLC with EGFR-activating mutations. However, acquired resistance, due partially to secondary mutations limits their use. Here we report that NSCLC cells with acquired resistance to gefitinib or osimertinib (AZD9291) exhibit EMT features, with a decrease in E-cadherin, and increases in vimentin and stemness, without possessing any EGFR secondary mutations. Knockdown of E-cadherin in parental cells increased gefitinib resistance and stemness, while knockdown of vimentin in resistant cells resulted in opposite effects. Src activation and Hakai upregulation were found in gefitinib-resistant cells. Knockdown of Hakai elevated E-cadherin expression, attenuated stemness, and resensitized the cells to gefitinib. Clinical cancer specimens with acquired gefitinib resistance also showed a decrease in E-cadherin and an increase in Hakai expression. The dual HDAC and HMGR inhibitor JMF3086 inhibited the Src/Hakai and Hakai/E-cadherin interaction to reverse E-cadherin expression, and attenuated vimentin and stemness to restore gefitinib sensitivity. The EMT features of AZD9291-resistant H1975 cells were related to the upregulation of Zeb1. Both gefitinib and AZD9291 sensitivity was restored by JMF3086 through reversing EMT. Our study not only revealed a common mechanism of EMT in both gefitinib and AZD9291 resistance beyond EGFR mutations per se, but also provides a new strategy to overcome it.
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Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Resistencia a Antineoplásicos/genética , Transición Epitelial-Mesenquimal/fisiología , Gefitinib/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Proteínas de Neoplasias/fisiología , Piperazinas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Acrilamidas , Compuestos de Anilina , Animales , Antígenos CD/biosíntesis , Antígenos CD/genética , Cadherinas/antagonistas & inhibidores , Cadherinas/biosíntesis , Cadherinas/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Resistencia a Antineoplásicos/fisiología , Ensayos de Selección de Medicamentos Antitumorales , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , Receptores ErbB/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/genética , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/patología , Interferencia de ARN , ARN Interferente Pequeño/farmacología , Organismos Libres de Patógenos Específicos , Ubiquitina-Proteína Ligasas/antagonistas & inhibidores , Ubiquitina-Proteína Ligasas/biosíntesis , Ubiquitina-Proteína Ligasas/genética , Vimentina/antagonistas & inhibidores , Vimentina/biosíntesis , Vimentina/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/biosíntesis , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/genéticaRESUMEN
Tamiflu readily undergoes endogenous hydrolysis to give oseltamivir carboxylic acid (OC) as the active anti-influenza agent to inhibit the viral neuraminidase (NA). GOC is derived from OC by replacing the 5-amino group with a guanidino group. In this study, OC and GOC congeners with the carboxylic acid bioisosteres of boronic acid, trifluoroborate, sulfone, sulfinic acid, sulfonic acid and sulfonate ester were first synthesized, starting with conversion of OC to a Barton ester, followed by halodecarboxylation to give the iodocyclohexene, which served as a pivotal intermediate for palladium-catalyzed coupling reactions with appropriate diboron and thiol reagents. The enzymatic and cell-based assays indicated that the GOC congeners consistently displayed better NA inhibition and anti-influenza activity than the corresponding OC congeners. The GOC sulfonic acid congener (7a) was the most potent anti-influenza agent, showing EC50â¯=â¯2.2â¯nM against the wild-type H1N1 virus, presumably because the sulfonic acid 7a was more lipophilic than GOC and exerted stronger interactions on the three arginine residues (R118, R292 and R371) in the NA active site. Although the trifluoroborates, sulfones and sulfonate esters did not have acidic proton, they still exhibited appreciable NA inhibitory activity, indicating that the polarized B-F and SâO bonds still made sufficient interactions with the tri-arginine motif.