ABSTRACT
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.
ABSTRACT
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.
Subject(s)
Enzyme Inhibitors , Signal Transduction , Enzyme Inhibitors/chemistry , Cell Proliferation , Cell Differentiation , BiologyABSTRACT
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.
ABSTRACT
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).
Subject(s)
Antiviral Agents/pharmacology , Peptides/pharmacology , Protease Inhibitors/pharmacology , Viral Nonstructural Proteins/antagonists & inhibitors , Zika Virus/drug effects , Antiviral Agents/chemical synthesis , Antiviral Agents/chemistry , Dengue Virus/drug effects , Dose-Response Relationship, Drug , Humans , Microbial Sensitivity Tests , Molecular Structure , Peptides/chemical synthesis , Peptides/chemistry , Protease Inhibitors/chemical synthesis , Protease Inhibitors/chemistry , RNA Helicases/antagonists & inhibitors , RNA Helicases/metabolism , Serine Endopeptidases/metabolism , Structure-Activity Relationship , Viral Nonstructural Proteins/metabolism , West Nile virus/drug effects , Zika Virus/enzymologyABSTRACT
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.
ABSTRACT
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.
ABSTRACT
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.
Subject(s)
Growth Inhibitors/chemistry , Piperazines/chemistry , Trypanocidal Agents/chemistry , Trypanosoma brucei brucei/drug effects , Trypanosomiasis, African/drug therapy , Cell Survival/drug effects , Drug Evaluation, Preclinical , Growth Inhibitors/pharmacology , Human Umbilical Vein Endothelial Cells , Humans , Isomerism , Morpholines/chemistry , Piperazines/pharmacology , Quinolines/chemistry , Structure-Activity Relationship , Trypanocidal Agents/pharmacologyABSTRACT
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.
ABSTRACT
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.
ABSTRACT
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).
Subject(s)
Piperazines/chemistry , Piperazines/pharmacology , Trypanocidal Agents/chemistry , Trypanocidal Agents/pharmacology , Trypanosoma brucei brucei/drug effects , Trypanosomiasis, African/drug therapy , HeLa Cells , Humans , Imidazoles/chemistry , Imidazoles/pharmacology , Malaria, Falciparum/drug therapy , Plasmodium falciparum/drug effects , Structure-Activity Relationship , Trypanosoma brucei brucei/growth & development , Trypanosomiasis, African/parasitologyABSTRACT
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.
ABSTRACT
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.
Subject(s)
Antineoplastic Agents/chemistry , Hedgehog Proteins/antagonists & inhibitors , Imidazoles/chemistry , Pyrazines/chemistry , Animals , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/therapeutic use , Dogs , Hedgehog Proteins/metabolism , Humans , Imidazoles/pharmacology , Imidazoles/therapeutic use , Mice , Neoplasms/drug therapy , Pyrazines/pharmacology , Pyrazines/therapeutic use , Rats , Signal Transduction/drug effects , Stereoisomerism , Structure-Activity RelationshipABSTRACT
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.
Subject(s)
Amides/chemical synthesis , Antineoplastic Agents/chemical synthesis , Azetidines/chemical synthesis , Enzyme Inhibitors/chemical synthesis , Indazoles/chemical synthesis , Poly(ADP-ribose) Polymerase Inhibitors , Amides/chemistry , Amides/pharmacology , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Azetidines/chemistry , Azetidines/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , HeLa Cells , Humans , Indazoles/chemistry , Indazoles/pharmacology , Poly(ADP-ribose) Polymerases/metabolism , Rats , Structure-Activity Relationship , Ubiquitin-Protein Ligases/deficiency , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolismABSTRACT
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.
Subject(s)
BRCA1 Protein/deficiency , Piperazines/chemical synthesis , Poly(ADP-ribose) Polymerase Inhibitors , Pyridazines/chemical synthesis , Animals , BRCA1 Protein/genetics , HeLa Cells , Humans , Microsomes, Liver/drug effects , Microsomes, Liver/enzymology , Piperazines/metabolism , Piperazines/pharmacology , Poly (ADP-Ribose) Polymerase-1 , Poly(ADP-ribose) Polymerases/metabolism , Pyridazines/metabolism , Pyridazines/pharmacology , RatsABSTRACT
5-Aryl-2-(trifluoroacetyl)thiophenes were identified as a new series of class II HDAC inhibitors (HDACi). Further development of this new series led to compounds such as 6h, a potent inhibitor of HDAC4 and HDAC6 (HDAC4 WT IC(50) = 310 nM, HDAC6 IC(50) = 70 nM) that displays 40-fold selectivity over HDAC1 and improved stability in HCT116 cancer cells (t(1/2) = 11 h). Compounds 6h and 2 show inhibition of alpha-tubulin deacetylation in HCT116 cells at 1 microM concentration and antiproliferation effects only at concentrations where inhibition of histone H3 deacetylation is observed.
Subject(s)
Antineoplastic Agents/chemical synthesis , Histone Deacetylase 2/antagonists & inhibitors , Repressor Proteins/antagonists & inhibitors , Thiophenes/chemical synthesis , Acetylation , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Histone Deacetylase 1/antagonists & inhibitors , Histone Deacetylase 6 , Histone Deacetylases/metabolism , Histones/metabolism , Humans , Isoenzymes/antagonists & inhibitors , Structure-Activity Relationship , Thiophenes/chemistry , Thiophenes/pharmacology , Tubulin/metabolismABSTRACT
We disclose the development of a novel series of 2-phenyl-2H-indazole-7-carboxamides as poly(ADP-ribose)polymerase (PARP) 1 and 2 inhibitors. This series was optimized to improve enzyme and cellular activity, and the resulting PARP inhibitors display antiproliferation activities against BRCA-1 and BRCA-2 deficient cancer cells, with high selectivity over BRCA proficient cells. Extrahepatic oxidation by CYP450 1A1 and 1A2 was identified as a metabolic concern, and strategies to improve pharmacokinetic properties are reported. These efforts culminated in the identification of 2-{4-[(3S)-piperidin-3-yl]phenyl}-2H-indazole-7-carboxamide 56 (MK-4827), which displays good pharmacokinetic properties and is currently in phase I clinical trials. This compound displays excellent PARP 1 and 2 inhibition with IC(50) = 3.8 and 2.1 nM, respectively, and in a whole cell assay, it inhibited PARP activity with EC(50) = 4 nM and inhibited proliferation of cancer cells with mutant BRCA-1 and BRCA-2 with CC(50) in the 10-100 nM range. Compound 56 was well tolerated in vivo and demonstrated efficacy as a single agent in a xenograft model of BRCA-1 deficient cancer.
Subject(s)
Amides/pharmacology , Drug Discovery , Genes, BRCA1 , Genes, BRCA2 , Indazoles/pharmacology , Mutation , Neoplasms/genetics , Piperidines/pharmacology , Poly(ADP-ribose) Polymerase Inhibitors , Administration, Oral , Amides/administration & dosage , Amides/chemistry , Amides/pharmacokinetics , Animals , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Transformation, Neoplastic , Drug Stability , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacokinetics , Enzyme Inhibitors/pharmacology , Female , Humans , Indazoles/administration & dosage , Indazoles/chemistry , Indazoles/pharmacokinetics , Inhibitory Concentration 50 , Neoplasms/enzymology , Neoplasms/pathology , Piperidines/administration & dosage , Piperidines/chemistry , Piperidines/pharmacokinetics , RatsABSTRACT
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.
Subject(s)
Amides/chemical synthesis , Indazoles/chemical synthesis , Receptors, G-Protein-Coupled/antagonists & inhibitors , Receptors, G-Protein-Coupled/chemistry , Amides/pharmacology , Catalysis , Cell Line , Chemistry, Pharmaceutical/methods , Combinatorial Chemistry Techniques/methods , Drug Design , Drug Evaluation, Preclinical , Humans , Indazoles/pharmacology , Inhibitory Concentration 50 , Models, Chemical , Signal Transduction , Smoothened Receptor , Structure-Activity RelationshipABSTRACT
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.
Subject(s)
Histone Deacetylase Inhibitors , Oxadiazoles/chemical synthesis , Oxadiazoles/pharmacology , Thiophenes/chemical synthesis , Thiophenes/pharmacology , Combinatorial Chemistry Techniques , Drug Design , HCT116 Cells , Histone Acetyltransferases/antagonists & inhibitors , Histone Deacetylases/classification , Humans , Molecular Structure , Oxadiazoles/chemistry , Structure-Activity Relationship , Thiophenes/chemistryABSTRACT
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.