RESUMO
Tyrosine phosphatase SHP2 is a proto-oncogenic protein involved in cell growth and differentiation via diverse intracellular signaling pathways. With the scope of identifying new SHP2 allosteric inhibitors, we report here the development and optimization of a high-throughput "Direct-to-Biology" (D2B) workflow including the synthesis and the biological evaluation of the reaction crude, thus eliminating the need for purification. During this labor-saving procedure, the structural diversity was introduced through a SNAr reaction. A wide array of analogues with good chemical purity was generated, allowing the obtention of reliable biological data which validated this efficient technique. This approach enabled the fast evaluation of a variety of structurally diverse fragments leading to nanomolar SHP2 allosteric inhibitors and a new series bearing a novel bicyclo[3.1.0]hexane moiety.
Assuntos
Inibidores Enzimáticos , Transdução de Sinais , Inibidores Enzimáticos/química , Proliferação de Células , Diferenciação Celular , BiologiaRESUMO
OBJECTIVES: Blood level of pancreatic stone protein (PSP) is a promising biomarker of sepsis both in adults and children. The aim of our study was to investigate the diagnostic accuracy of PSP in children with suspected sepsis and to compare diagnostic performance with other sepsis biomarkers approved for clinical use, that is, procalcitonin (PCT) and C-reactive protein (CRP). DESIGN: Prospective study. SETTING: PICU and pediatric emergency department. INTERVENTION: Blood levels of PSP were measured using a nanofluidic point-of-care immunoassay (abioSCOPE, Abionic SA, Switzerland) within 24 hours of admission. MEASUREMENTS AND MAIN RESULTS: We studied 99 children aged between older than 1 month and younger than 18 years with signs and symptoms of systemic inflammatory response syndrome (irrespective of associated organ dysfunction). The prevalence of sepsis was 35 of 99 (35.4%). Patients with sepsis had higher PSP levels (p < 0.001) than patients with systemic inflammation of noninfectious cause. In this analysis, the optimal cutoff for the diagnosis of sepsis using PSP was 123 ng/mL, which resulted in a sensitivity of 0.63 (95% CI, 0.43-0.80), specificity of 0.89 (95% CI, 0.77-0.95). The PSP test area under the receiver operating characteristic curve (AUROC) was 0.82 (95% CI, 0.73-0.91) and, by comparison, procalcitonin and CRP AUROC were 0.70 (95% CI, 0.58-0.82) and 0.72 (95% CI, 0.60-0.84), respectively. Overall, the pretest to posttest probability of sepsis with a positive test changed from 0.35 to 0.73. CONCLUSIONS: In this single-center prospective pediatric cohort, admitted to the high intensive care and to the PICU, our findings suggested the potential use of PSP as a sepsis biomarker. However, because of the clinical diagnostic uncertainty with a positive result, further investigation is needed particularly in combination with other biomarkers.
RESUMO
Zika virus (ZIKV) is a member of the Flaviviridae family that can cause neurological disorders and congenital malformations. The NS2B-NS3 viral serine protease is an attractive target for the development of new antiviral agents against ZIKV. We report here a SAR study on a series of substrate-like linear tripeptides that inhibit in a non-covalent manner the NS2B-NS3 protease. Optimization of the residues at positions P1, P2, P3 and of the N-terminal and C-terminal portions of the tripeptide allowed the identification of inhibitors with sub-micromolar potency with phenylglycine as arginine-mimicking group and benzylamide as C-terminal fragment. Further SAR exploration and application of these structural changes to a series of peptides having a 4-substituted phenylglycine residue at the P1 position led to potent compounds showing double digit nanomolar inhibition of the Zika protease (IC50 = 30 nM) with high selectivity against trypsin-like proteases and the proteases of other flavivirus, such as Dengue 2 virus (DEN2V) and West Nile virus (WNV).
Assuntos
Antivirais/farmacologia , Peptídeos/farmacologia , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Zika virus/efeitos dos fármacos , Antivirais/síntese química , Antivirais/química , Vírus da Dengue/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Peptídeos/síntese química , Peptídeos/química , Inibidores de Proteases/síntese química , Inibidores de Proteases/química , RNA Helicases/antagonistas & inibidores , RNA Helicases/metabolismo , Serina Endopeptidases/metabolismo , Relação Estrutura-Atividade , Proteínas não Estruturais Virais/metabolismo , Vírus do Nilo Ocidental/efeitos dos fármacos , Zika virus/enzimologiaRESUMO
A previous publication from our laboratory reported the identification of a new class of 2-(1H-imidazo-2-yl)piperazines as potent T. brucei growth inhibitors as potential treatment for Human African Trypanosomiasis (HAT). This work describes the structure-activity relationship (SAR) around the hit compound 1, which led to the identification of the optimized compound 18, a single digit nanomolar inhibitor (EC50 7 nM), not cytotoxic and with optimal in vivo profile that made it a suitable candidate for efficacy studies in a mouse model mimicking the second stage of disease.
Assuntos
Inibidores do Crescimento/química , Piperazinas/química , Tripanossomicidas/química , Trypanosoma brucei brucei/efeitos dos fármacos , Tripanossomíase Africana/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Inibidores do Crescimento/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Isomerismo , Morfolinas/química , Piperazinas/farmacologia , Quinolinas/química , Relação Estrutura-Atividade , Tripanossomicidas/farmacologiaRESUMO
The identification of a new series of growth inhibitors of Trypanosoma brucei rhodesiense, causative agent of Human African Trypanosomiasis (HAT), is described. A selection of compounds from our in-house compound collection was screened in vitro against the parasite leading to the identification of compounds with nanomolar inhibition of T. brucei growth. Preliminary SAR on the hit compound led to the identification of compound 34 that shows low nanomolar parasite growth inhibition (T. brucei EC50 5â¯nM), is not cytotoxic (HeLa CC50â¯>â¯25,000â¯nM) and is selective over other parasites, such as Trypanosoma cruzi and Plasmodium falciparum (T. cruzi EC50 8120â¯nM, P. falciparum EC50 3624â¯nM).
Assuntos
Piperazinas/química , Piperazinas/farmacologia , Tripanossomicidas/química , Tripanossomicidas/farmacologia , Trypanosoma brucei brucei/efeitos dos fármacos , Tripanossomíase Africana/tratamento farmacológico , Células HeLa , Humanos , Imidazóis/química , Imidazóis/farmacologia , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Relação Estrutura-Atividade , Trypanosoma brucei brucei/crescimento & desenvolvimento , Tripanossomíase Africana/parasitologiaRESUMO
Sotos syndrome is an autosomal dominant condition characterized by overgrowth with advanced bone age, macrodolicocephaly, motor developmental delays and learning difficulties, and characteristic facial features caused by heterozygous pathogenetic variants in the NSD1 gene located on chromosome 5q35. The prevalence of heart defects (HDs) in individuals with Sotos syndrome is estimated to be around 15-40%. Septal defects and patent ductus arteriosus are the most commonly diagnosed malformations, but complex defects have also been reported. The aim of our study was to analyze the prevalence of HD, the anatomic types, and the genetic characteristics of 45 patients with Sotos syndrome carrying pathogenetic variants of NSD1 or a 5q35 deletion encompassing NSD1, who were followed at Bambino Gesù Children's Hospital in Rome. Thirty-nine of the forty-five patients (86.7%) had a mutation in NSD1, while six of the forty-five (13.3%) had a deletion. Most of the patients (62.2%, 28/45) were male, with a mean age of 14 ± 7 years (range 0.2-37 years). A total of 27/45 (60.0%) of the patients had heart defects, isolated or combined with other defects, including septal defects (12 patients), aortic anomalies (9 patients), mitral valve and/or tricuspid valve dysplasia/insufficiency (1 patient), patent ductus arteriosus (3 patients), left ventricular non-compaction/hypertrabeculated left ventricle (LV) (4 patients), aortic coarctation (1 patient), aortopulmonary window (1 patient), and pulmonary valve anomalies (3 patients). The prevalences of HD in the two subgroups (deletion versus intragenic mutation) were similar (66.7% (4/6) in the deletion group versus 58.91% (23/39) in the intragenic variant group). Our results showed a higher prevalence of HD in patients with Sotos syndrome in comparison to that described in the literature, with similar distributions of patients with mutated and deleted genes. An accurate and detailed echocardiogram should be performed in patients with Sotos syndrome at diagnosis, and a specific cardiological follow-up program is needed.
RESUMO
Protein tyrosine phosphatase SHP2 is an oncogenic protein that can regulate different cytokine receptor and receptor tyrosine kinase signaling pathways. We report here the identification of a novel series of SHP2 allosteric inhibitors having an imidazopyrazine 6,5-fused heterocyclic system as the central scaffold that displays good potency in enzymatic and cellular assays. SAR studies led to the identification of compound 8, a highly potent SHP2 allosteric inhibitor. X-ray studies showed novel stabilizing interactions with respect to known SHP2 inhibitors. Subsequent optimization allowed us to identify analogue 10, which possesses excellent potency and a promising PK profile in rodents.
RESUMO
Jacobsen syndrome (JS) is a rare syndrome caused by a deletion of chromosome 11q. We report a patient with JS and hypoplastic left heart syndrome (HLHS) who required cardiac transplantation. She had many of the recognized morphological features in addition to immunological (lymphopenia) and hematological (thrombocytopenia) issues. The patient underwent a Norwood procedure with a modified Blalock-Taussig shunt (MBTS) and subsequently a Glenn procedure at six months of age. She developed desaturation, with severe tricuspid regurgitation and right ventricular dysfunction, and underwent heart transplantation at 7 months of age. After the transplant, she was hospitalized several times for severe infections. The diagnosis of Jacobsen syndrome came 2 months after transplant. Now, 5 years post-transplant, she is in relatively good health-her heart is functioning normally, her hospitalization rate is getting lower, and her immunological profile is stable.
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The Hedgehog (Hh-) signaling pathway is a key developmental pathway which gets reactivated in many human tumors, and smoothened (Smo) antagonists are emerging as novel agents for the treatment of malignancies dependent on the Hh-pathway, with the most advanced compounds demonstrating encouraging results in initial clinical trials. A novel series of potent bicyclic hydantoin Smo antagonists was reported in the preceding article, these have been resolved, and optimized to identify potent homochiral derivatives with clean off-target profiles and good pharmacokinetic properties in preclinical species. While showing in vivo efficacy in mouse allograft models, unsubstituted bicyclic tetrahydroimidazo[1,5-a]pyrazine-1,3(2H,5H)-diones were shown to epimerize in plasma. Alkylation of the C-8 position blocks this epimerization, resulting in the identification of MK-5710 (47) which was selected for further development.
Assuntos
Antineoplásicos/química , Proteínas Hedgehog/antagonistas & inibidores , Imidazóis/química , Pirazinas/química , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Cães , Proteínas Hedgehog/metabolismo , Humanos , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Camundongos , Neoplasias/tratamento farmacológico , Pirazinas/farmacologia , Pirazinas/uso terapêutico , Ratos , Transdução de Sinais/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
A potent series of substituted 2-phenyl-2H-indazole-7-carboxamides were synthesized and evaluated as inhibitors of poly (ADP-ribose) polymerase (PARP). This extensive SAR exploration culminated with the identification of substituted 5-fluoro-2-phenyl-2H-indazole-7-carboxamide analog 48 which displayed excellent PARP enzyme inhibition with IC(50)=4nM, inhibited proliferation of cancer cell lines deficient in BRCA-1 with CC(50)=42nM and showed encouraging pharmacokinetic properties in rats compared to the lead 6.
Assuntos
Amidas/síntese química , Antineoplásicos/síntese química , Azetidinas/síntese química , Inibidores Enzimáticos/síntese química , Indazóis/síntese química , Inibidores de Poli(ADP-Ribose) Polimerases , Amidas/química , Amidas/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Azetidinas/química , Azetidinas/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Células HeLa , Humanos , Indazóis/química , Indazóis/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Ratos , Relação Estrutura-Atividade , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
We describe an extensive SAR study in the 6-[4-fluoro-3-(substituted)benzyl]-4,5-dimethylpyridazin-3(2H)-one series which led to the identification of potent PARP-1 inhibitors, capable of inhibiting the proliferation of BRCA-1 deficient cancer cells in the low nanomolar range, and displaying >100-fold selectivity over the BRCA wild type counterparts. The series of compounds was devoid of hERG channel activity, and CYP inhibition and induction liabilities. Several analogs were stable in rat and human liver microsomes and displayed moderate rat clearance, with urinary excretion of parent as the major route of elimination.
Assuntos
Proteína BRCA1/deficiência , Piperazinas/síntese química , Inibidores de Poli(ADP-Ribose) Polimerases , Piridazinas/síntese química , Animais , Proteína BRCA1/genética , Células HeLa , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Piperazinas/metabolismo , Piperazinas/farmacologia , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Piridazinas/metabolismo , Piridazinas/farmacologia , RatosRESUMO
Rhodolith beds (RBs) are bioconstructions characterized by coralline algae, which provide habitat for several associated species. Mediterranean RBs are usually located in the mesophotic zone (below 40 m), and thus are frequently remote and unexplored. Recently, the importance and vulnerability of these habitats have been recognized by the European Community and more attention has been drawn to their investigation and conservation. This study reports the results of an extensive monitoring program, carried out within the Marine Strategy Framework Directive (2008/56/EC), in six sites off the Campania coast (Italy, Mediterranean Sea). New insights were given into the distribution, cover, vitality (i.e., live/dead rhodolith ratio), structural complexity, and coralline algae composition of RBs. Remotely operated vehicles (ROV) investigations allowed the description of several RBs, and the discovery of a RB with rhodolith cover >65% offshore the Capri Island. Only two sites (Secchitiello and Punta Campanella) showed a very low mean cover of live rhodoliths (<10%); hence, not being classifiable as RBs. The collected rhodoliths were mostly small pralines (~2 cm), spheroidal to ellipsoidal, with growth-forms ranging from encrusting/warty to fruticose/lumpy. Coralline algae identification revealed a high diversity within each bed, with a total of 13 identified taxa. The genus Lithothamnion dominated all sites, and Phymatolithon calcareum and Lithothamnion corallioides, protected by the Habitats Directive (92/43/EEC), were detected in all RBs.
RESUMO
The NRF2-ARE pathway is an intrinsic mechanism of defense against oxidative stress. Inhibition of the interaction between NRF2 and its main negative regulator KEAP1 is an attractive strategy toward neuroprotective agents. We report here the identification of nonacidic tetrahydroisoquinolines (THIQs) that inhibit the KEAP1/NRF2 protein-protein interaction. Peptide SAR at one residue is utilized as a tool to probe structural changes within a specific pocket of the KEAP1 binding site. We used structural information from peptide screening at the P2 pocket, noncovalent small-molecules inhibitors, and the outcome from an explorative SAR at position 5 of THIQs to identify a series of neutral THIQ analogs that bind to KEAP1 in the low micromolar range. These analogs establish new H-bond interactions at the P3 and P2 pockets allowing the replacement of the carboxylic acid functionality by a neutral primary carboxamide. X-ray crystallographic studies reveal the novel binding mode of these molecules to KEAP1.
RESUMO
We report the synthesis and biological evaluation of N-[(1-aryl-1H-indazol-5-yl)methyl]amide derivatives as Smoothened antagonists and inhibitors of the Hedgehog pathway. Identification of the lead structure 1 by HTS, followed by SAR study on the amide and aryl portions led to the discovery of antagonists with nanomolar activity.
Assuntos
Amidas/síntese química , Indazóis/síntese química , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/química , Amidas/farmacologia , Catálise , Linhagem Celular , Química Farmacêutica/métodos , Técnicas de Química Combinatória/métodos , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Indazóis/farmacologia , Concentração Inibidora 50 , Modelos Químicos , Transdução de Sinais , Receptor Smoothened , Relação Estrutura-AtividadeRESUMO
The application of class I HDAC inhibitors as cancer therapies is well established, but more recently their development for nononcological indications has increased. We report here on the generation of improved class I selective human HDAC inhibitors based on an ethylketone zinc binding group (ZBG) in place of the hydroxamic acid that features the majority of HDAC inhibitors. We also describe a novel set of HDAC3 isoform selective inhibitors that show stronger potency and selectivity than the most commonly used HDAC3 selective tool compound RGFP966. These compounds are again based on an alternative ZBG with respect to the ortho-anilide that is featured in HDAC3 selective compounds reported to date.
RESUMO
Trifluoroacetylthiophene carboxamides have recently been reported to be class II HDAC inhibitors, with moderate selectivity. Exploration of replacements for the carboxamide with bioisosteric pentatomic heteroaromatic like 1,3,4-oxadiazoles, 1,2,4-oxadiazoles and 1,3-thiazoles, led to the discovery that 2-trifluoroacetylthiophene 1,3,4-oxadiazole derivatives are very potent low nanomolar HDAC4 inhibitors, highly selective over class I HDACs (HDAC 1 and 3), and moderately stable in HCT116 cell culture.
Assuntos
Inibidores de Histona Desacetilases , Oxidiazóis/síntese química , Oxidiazóis/farmacologia , Tiofenos/síntese química , Tiofenos/farmacologia , Técnicas de Química Combinatória , Desenho de Fármacos , Células HCT116 , Histona Acetiltransferases/antagonistas & inibidores , Histona Desacetilases/classificação , Humanos , Estrutura Molecular , Oxidiazóis/química , Relação Estrutura-Atividade , Tiofenos/químicaRESUMO
The identification of class II HDAC inhibitors has been hampered by lack of efficient enzyme assays, in the preceding paper two assays have been developed to improve the efficiency of these enzymes: mutating an active site histidine to tyrosine, or by the use of a trifluoroacetamide lysine substrate, allowing screening to identify class II HDAC inhibitors. Herein, 2-trifluoroacetylthiophenes have been demonstrated to inhibit class II HDACs, resulting in the development of a series of 5-(trifluoroacetyl)thiophene-2-carboxamides as novel, potent and selective class II HDAC inhibitors. X-ray crystal structures of the HDAC 4 catalytic domain with a bound inhibitor demonstrate these compounds are active site inhibitors and bind in their hydrated form.
Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Inibidores de Histona Desacetilases , Tiofenos/síntese química , Sítios de Ligação , Cristalografia por Raios X , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Histona Desacetilases/classificação , Conformação Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Tiofenos/química , Tiofenos/farmacologia , Zinco/química , Zinco/metabolismoRESUMO
5-(Trifluoroacetyl)thiophene-2-carboxamides were found to be potent and selective class II HDAC inhibitors. This paper describes their further development and the investigation on the cause for the lack of cell-based activity. A rapid screening assay was set up which enabled the identification of more metabolic stable compounds as potent and selective class II HDAC inhibitors.
Assuntos
Amidas/síntese química , Amidas/farmacologia , Inibidores de Histona Desacetilases , Tiofenos/síntese química , Tiofenos/farmacologia , Amidas/química , Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Citocromo P-450 CYP2C9 , Desenho de Fármacos , Células HCT116 , Células HeLa , Hepatócitos/efeitos dos fármacos , Histona Desacetilases/classificação , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Estrutura Molecular , Relação Estrutura-Atividade , Tiofenos/química , Tubulina (Proteína)/efeitos dos fármacosRESUMO
The identification of a new series of P. falciparum growth inhibitors is described. Starting from a series of known human class I HDAC inhibitors a SAR exploration based on growth inhibitory activity in parasite and human cells-based assays led to the identification of compounds with submicromolar inhibition of P. falciparum growth (EC50 < 500 nM) and good selectivity over the activity of human HDAC in cells (up to >50-fold). Inhibition of parasital HDACs as the mechanism of action of this new class of selective growth inhibitors is supported by hyperacetylation studies.