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1.
Rinsho Shinkeigaku ; 64(6): 413-416, 2024 Jun 27.
Artigo em Japonês | MEDLINE | ID: mdl-38797686

RESUMO

A 54-year-old man with a university degree was admitted to our hospital because of a two-year history of progressive dementia. He had familial sensorineural hearing loss and had been treated for epilepsy since his 30s. On admission, he showed severe dementia and parkinsonism without fever or skin rash. Systemic inflammation was evident, and the CSF cell count and IL-6 level were elevated to 53/µl and 307 |pg/ml, respectively. Brain MRI demonstrated diffuse brain atrophy. More detailed anamnesis revealed a history of rheumatoid arthritis in childhood and aseptic meningitis in his 20s. Genetic examination for autoinflammatory diseases demonstrated compound heterozygotic mutations in the NLRP3 gene, causing cryopyrin-associated periodic fever syndrome (CAPS). This case was atypical CAPS presenting as early-onset progressive dementia, without recurrent fever or urticaria-like eruption which are usually seen in this disease.


Assuntos
Síndromes Periódicas Associadas à Criopirina , Demência , Mutação , Proteína 3 que Contém Domínio de Pirina da Família NLR , Humanos , Síndromes Periódicas Associadas à Criopirina/diagnóstico , Síndromes Periódicas Associadas à Criopirina/complicações , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Pessoa de Meia-Idade , Demência/etiologia , Demência/diagnóstico , Exantema/etiologia , Febre/etiologia , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Diagnóstico Diferencial , Heterozigoto , Biomarcadores/líquido cefalorraquidiano , Biomarcadores/sangue , Progressão da Doença
2.
Cancers (Basel) ; 15(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38067389

RESUMO

[Proposal] Here, we retrospectively evaluate risk factors for radiation necrosis and local recurrence after PBT for skull base chordoma or chondrosarcoma. [Patients and Methods] We analyzed 101 patients who received PBT for skull base chordomas and chondrosarcomas from January 1989 to February 2021. Multivariable logistic regression models were applied for local recurrence, temporal lobe radiation necrosis rates, and temporal lobe radiation necrosis. [Results] In multivariate analysis, chordoma and large tumor size were independent significant factors for local recurrence. The 1-, 2-, 3-, 4- and 5-year local recurrence rates were 3.9%, 16.9%, 20.3%, 28.5% and 44.0% for chordoma and 0%, 0%, 0%, 0% and 7.1% for chondrosarcoma, respectively. The local recurrence rates of small tumors (<30 mm) were 4.3%, 14.7%, 17.7%, 17.7% and 25.9%, and those for large tumors were 3.6%, 15.1%, 19.2%, 32.7% and 59.6%, respectively. In multivariate analysis, BED Gy10 and total dose were risk factors for radiation necrosis. [Conclusions] For skull base chordoma and chondrosarcoma, the risk factors of local recurrence were chordoma and large tumor size, and those of radiation necrosis were BED Gy10 and total dose, respectively. DVH analysis is needed to investigate the risk factors for brain necrosis in more detail.

3.
RSC Med Chem ; 14(12): 2731-2737, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38107172

RESUMO

Several generations of ATP-competitive anti-cancer drugs that inhibit the activity of the intracellular kinase domain of the epidermal growth factor receptor (EGFR) have been developed over the past twenty years. The first-generation of drugs such as gefitinib bind reversibly and were followed by a second-generation such as dacomitinib that harbor an acrylamide moiety that forms a covalent bond with C797 in the ATP binding pocket. Resistance emerges through mutation of the T790 gatekeeper residue to methionine, which introduces steric hindrance to drug binding and increases the Km for ATP. A third generation of drugs, such as osimertinib were developed which were effective against T790M EGFR in which an acrylamide moiety forms a covalent bond with C797, although resistance has emerged by mutation to S797. A fragment-based screen to identify new starting points for an EGFR inhibitor serendipitously identified a fragment that reacted with C775, a previously unexploited residue in the ATP binding pocket for a covalent inhibitor to target. A number of acrylamide containing fragments were identified that selectively reacted with C775. One of these acrylamides was optimized to a highly selective inhibitor with sub-1 µM activity, that is active against T790M, C797S mutant EGFR independent of ATP concentration, providing a potential new strategy for pan-EGFR mutant inhibition.

4.
Exp Ther Med ; 26(5): 510, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37840568

RESUMO

The abscopal effect is a rare phenomenon that is defined as regression of tumor lesions distant from irradiation targets. At our department, two cases with an abscopal effect with fever of unknown cause (FUC) and an inflammatory response during radiotherapy were encountered. Radiotherapy is a local treatment; therefore, it rarely causes systemic side effects during radiotherapy, and if a patient develops a fever during radiotherapy, it is frequently considered tumor fever. We experienced 2 cases of FUC during irradiation followed by abscopal effect. The obvious relationship between the abscopal effect and the fever remains to be clarified. However, FUC during radiotherapy may be a hint to the abscopal effect, considering that immune response and cytokines are closely related to the abscopal effect.

5.
BMC Gastroenterol ; 23(1): 267, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537527

RESUMO

AIM: Hepatocellular carcinoma (HCC) with bile duct invasion (BDI) (BDIHCC) has a poor prognosis. Moreover, due to the paucity of reports, there is no consensus regarding optimal management of this clinical condition yet. The aim of this study was to clarify the efficacy and safety of proton beam therapy (PBT) for BDIHCC. METHODS: Between 2009 and 2018, 15 patients with BDIHCC underwent PBT at our institution. The overall survival (OS), local control (LC), and progression-free survival (PFS) curves were constructed using the Kaplan-Meier method. Toxicities were assessed using the Common Terminology Criteria of Adverse Events version 4.0. RESULTS: The median follow-up time was 23.4 months (range, 7.9-54.3). The median age was 71 years (range, 58-90 years). Many patients were Child A (n = 8, 53.3%) and most had solitary tumors (n = 11, 73.3%). Additionally, most patients had central type BDI (n = 11, 73%). The median tumor size was 4.0 cm (range, 1.5-8.0 cm). The 1-, 2-, and 3-year OS rates were 80.0%, 58.7% and 40.2%, respectively, and the corresponding LC and PFS rates were 93.3%, 93.3%, and 74.7% and 72.7%, 9.7%, and 0.0%, respectively. Acute grade 1/2 dermatitis (n = 7, 46.7%), and grades 2 (n = 1, 6.7%) and 3 (n = 1, 6.7%) cholangitis were observed. Late toxicities such as grade 3 gastric hemorrhage and pleural effusion were observed. No toxicities of grade 4 or higher were observed. CONCLUSIONS: PBT was feasible with tolerable toxicities for the treatment of BDIHCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Terapia com Prótons , Idoso , Humanos , Ductos Biliares , Intervalo Livre de Progressão , Terapia com Prótons/efeitos adversos , Terapia com Prótons/métodos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais
6.
Heliyon ; 9(4): e14799, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37025861

RESUMO

Some oncoproteins along with stress kinase general control non-derepressible 2 (GCN2) can ensure the induction of activating transcription factor 4 (ATF4) to counteract amino acid deprivation; however, little is known regarding the role of the oncogenic EGFR-PI3K pathway. In this study, we demonstrate that both mutated EGFR and PIK3CA contribute to ATF4 induction following GCN2 activation in NSCLC cells. The inhibition of EGFR or PI3K mutant proteins, pharmacologically or through genetic knockdown, inhibited ATF4 induction without affecting GCN2 activation. A downstream analysis revealed that the oncogenic EGFR-PI3K pathway may utilize mTOR-mediated translation control mechanisms for ATF4 induction. Furthermore, in NSCLC cells harboring co-mutations in EGFR and PIK3CA, the combined inhibition of these oncoproteins markedly suppressed ATF4 induction and the subsequent gene expression program as well as cell viability during amino acid deprivation. Our findings establish a role for the oncogenic EGFR-PI3K pathway in the adaptive stress response and provide a strategy to improve EGFR-targeted NSCLC therapy.

7.
PLoS One ; 18(1): e0280560, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36662808

RESUMO

Calorie restriction (CR) suppresses not only spontaneous but also chemical- and radiation-induced carcinogenesis. Our previous study revealed that the cancer-preventive effect of CR is tissue dependent and that CR does not effectively prevent the development of thymic lymphoma (TL). We investigated the association between CR and the genomic alterations of resulting TLs to clarify the underlying resistance mechanism. TLs were obtained from previous and new experiments, in which B6C3F1 mice were exposed to radiation at 1 week of age and fed with a CR or standard (non-CR) diet from 7 weeks throughout their lifetimes. All available TLs were used for analysis of genomic DNA. In contrast to the TLs of the non-CR group, those of the CR group displayed suppression of copy-neutral loss of heterozygosity (LOH) involving relevant tumor suppressor genes (Cdkn2a, Ikzf1, Trp53, Pten), an event regarded as cell division-associated. However, CR did not affect interstitial deletions of those genes, which were observed in both groups. In addition, CR affected the mechanism of Ikzf1 inactivation in TLs: the non-CR group exhibited copy-neutral LOH with duplicated inactive alleles, whereas the CR group showed expression of dominant-negative isoforms accompanying a point mutation or an intragenic deletion. These results suggest that, even though CR reduces cell division-related genomic rearrangements by suppressing cell proliferation, tumors arise via diverse carcinogenic pathways including inactivation of tumor suppressors via interstitial deletions and other mutations. These findings provide a molecular basis for improved prevention strategies that overcome the CR resistance of lymphomagenesis.


Assuntos
Neoplasias Induzidas por Radiação , Neoplasias do Timo , Camundongos , Animais , Restrição Calórica , Mutação , Neoplasias do Timo/genética , Mutação Puntual , Alelos , Perda de Heterozigosidade , Neoplasias Induzidas por Radiação/genética
8.
J Med Chem ; 66(1): 695-715, 2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-36572866

RESUMO

Histone acetylation is a post-translational modification of histones that is catalyzed by histone acetyltransferases (HATs) and plays an essential role in cellular processes. The HAT domain of EP300/CBP has recently emerged as a potential drug target for cancer therapy. Here, we describe the identification of the novel, highly potent, and selective EP300/CBP HAT inhibitor DS-9300. Our optimization efforts using a structure-based drug design approach based on the cocrystal structures of the EP300 HAT domain in complex with compounds 2 and 3 led to the identification of compounds possessing low-nanomolar EP300 HAT inhibitory potency and the ability to inhibit cellular acetylation of histone H3K27. Optimization of the pharmacokinetic properties in this series resulted in compounds with excellent oral systemic exposure, and once-daily oral administration of 16 (DS-9300) demonstrated potent antitumor effects in a castrated VCaP xenograft mouse model without significant body weight loss.


Assuntos
Histona Acetiltransferases , Histonas , Humanos , Camundongos , Animais , Histonas/metabolismo , Histona Acetiltransferases/metabolismo , Acetilação , Fatores de Transcrição de p300-CBP , Proteína p300 Associada a E1A
9.
Bioorg Med Chem Lett ; 66: 128726, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35413416

RESUMO

EP300 and its paralog CBP play an important role in post-translational modification as histone acetyltransferases (HATs). EP300/CBP inhibition has been gaining attention as an anticancer treatment target in recent years. Herein, we describe the identification of a novel, highly selective EP300/CBP inhibitor, compound 11 (DS17701585), by scaffold hopping and structure-based optimization of a high-throughput screening hit 1. Compound 11 (DS17701585) shows dose-dependent inhibition of SRY-box transcription factor 2 (SOX2) mRNA expression in a human lung squamous cell carcinoma cell line LK2-xenografted mouse model.


Assuntos
Histona Acetiltransferases , Animais , Camundongos
10.
Mol Pharmacol ; 98(6): 669-676, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33033108

RESUMO

Eukaryotic initiation factor 2α (eIF2α) kinase general control nonderepressible 2 (GCN2) drives cellular adaptation to amino acid limitation by activating the integrated stress response that induces activating transcription factor 4 (ATF4). Here, we found that a multikinase inhibitor, GZD824, which we identified using a cell-based assay with ATF4 immunostaining, inhibited the GCN2 pathway in cancer cells. Indeed, GZD824 suppressed GCN2 activation, eIF2α phosphorylation, and ATF4 induction during amino acid starvation stress. However, at lower nonsuppressive concentrations, GZD824 paradoxically stimulated eIF2α phosphorylation and ATF4 expression in a GCN2-dependent manner under unstressed conditions. Such dual properties conceivably arose from a direct effect on GCN2, as also observed in a cell-free GCN2 kinase assay and shared by a selective GCN2 inhibitor. Consistent with the GCN2 pathway inhibition, GZD824 sensitized certain cancer cells to amino acid starvation stress similarly to ATF4 knockdown. These results establish GZD824 as a multikinase GCN2 inhibitor and may enhance its utility as a drug under development. SIGNIFICANCE STATEMENT: GZD824, as a direct general control nonderepressible 2 (GCN2) inhibitor, suppresses activation of the integrated stress response during amino acid limitation, whereas it paradoxically stimulates this stress-signaling pathway at lower nonsuppressive concentrations. The pharmacological activity we identify herein will provide the basis for the use of GZD824 to elucidate the regulatory mechanisms of GCN2 and to evaluate the potential of the GCN2-activating transcription factor 4 pathway as a target for cancer therapy.


Assuntos
Benzamidas/farmacologia , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirazóis/farmacologia , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Aminoácidos/metabolismo , Benzamidas/uso terapêutico , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Fator de Iniciação 2 em Eucariotos/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Neoplasias/patologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Pirazóis/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico
11.
Mol Cancer Ther ; 18(10): 1832-1843, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31350344

RESUMO

The FGFR4/FGF19 signaling axis is overactivated in 20% of liver tumors and currently represents a promising targetable signaling mechanism in this cancer type. However, blocking FGFR4 or FGF19 has proven challenging due to its physiological role in suppressing bile acid synthesis which leads to increased toxic bile acid plasma levels upon FGFR4 inhibition. An FGFR4-targeting antibody, U3-1784, was generated in order to investigate its suitability as a cancer treatment without major side effects.U3-1784 is a high-affinity fully human antibody that was obtained by phage display technology and specifically binds to FGFR4. The antibody inhibits cell signaling by competing with various FGFs for their FGFR4 binding site thereby inhibiting receptor activation and downstream signaling via FRS2 and Erk. The inhibitory effect on tumor growth was investigated in 10 different liver cancer models in vivo The antibody specifically slowed tumor growth of models overexpressing FGF19 by up to 90% whereas tumor growth of models not expressing FGF19 was unaffected. In cynomolgus monkeys, intravenous injection of U3-1784 caused elevated serum bile acid and liver enzyme levels indicating potential liver damage. These effects could be completely prevented by the concomitant oral treatment with the bile acid sequestrant colestyramine, which binds and eliminates bile acids in the gut. These results offer a new biomarker-driven treatment modality in liver cancer without toxicity and they suggest a general strategy for avoiding adverse events with FGFR4 inhibitors.


Assuntos
Anticorpos Monoclonais/toxicidade , Anticorpos Monoclonais/uso terapêutico , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/imunologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Resina de Colestiramina/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Íleo/efeitos dos fármacos , Íleo/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Células NIH 3T3 , Transdução de Sinais/efeitos dos fármacos , Sorafenibe/farmacologia
12.
Bioorg Med Chem ; 21(22): 7025-37, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24094436

RESUMO

5-Carbamoyl-2-phenylpyrimidine derivative 2 has been identified as a phosphodiesterase 4 (PDE4) inhibitor with moderate PDE4B inhibitory activity (IC50=200 nM). Modification of the carboxylic acid moiety of 2 gave N-neopentylacetamide derivative 10f, which had high in vitro PDE4B inhibitory activity (IC50=8.3 nM) and in vivo efficacy against lipopolysaccharide (LPS)-induced pulmonary neutrophilia in mice (ID50=16 mg/kg, ip). Furthermore, based on the X-ray crystallography of 10f bound to the human PDE4B catalytic domain, we designed 7,8-dihydro-6H-pyrido[4,3-d]pyrimidin-5-one derivative 39 which has a fused bicyclic lactam scaffold. Compound 39 exhibited excellent inhibitory activity against LPS-induced tumor necrosis factor alpha (TNF-α) production in mouse splenocytes (IC50=0.21 nM) and in vivo anti-inflammatory activity against LPS-induced pulmonary neutrophilia in mice (41% inhibition at a dose of 1.0 mg/kg, i.t.).


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/química , Inibidores da Fosfodiesterase 4/síntese química , Inibidores da Fosfodiesterase 4/farmacologia , Piridonas/síntese química , Piridonas/farmacologia , Pirimidinas/síntese química , Pirimidinas/farmacologia , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Sítios de Ligação , Domínio Catalítico , Células Cultivadas , Cristalografia por Raios X , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Lipopolissacarídeos/toxicidade , Pneumopatias/induzido quimicamente , Pneumopatias/tratamento farmacológico , Camundongos , Inibidores da Fosfodiesterase 4/uso terapêutico , Piridonas/uso terapêutico , Pirimidinas/química , Pirimidinas/uso terapêutico , Baço/citologia , Baço/efeitos dos fármacos , Baço/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
13.
Bioorg Med Chem Lett ; 23(11): 3325-8, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23602400

RESUMO

2-Phenyl-4-piperidinyl-6,7-dihydrothieno[3,4-d]pyrimidine derivative (2) was found to be a new PDE4 inhibitor with moderate PDE4B activity (IC50=150 nM). A number of derivatives with a variety of 4-amino substituents and fused bicyclic pyrimidines were synthesized. Among these, 5,5-dioxo-7,8-dihydro-6H-thiopyrano[3,2-d]pyrimidine derivative (18) showed potent PDE4B inhibitory activity (IC50=25 nM). Finally, N-propylacetamide derivative (31b) was determined as a potent inhibitor for both PDE4B (IC50=7.5 nM) and TNF-α production in mouse splenocytes (IC50=9.8 nM) and showed good in vivo anti-inflammatory activity in the LPS-induced lung inflammation model in mice (ID50=18 mg/kg). The binding mode of the new inhibitor (31e) in the catalytic site of PDE4B is presented based on an X-ray crystal structure of the ligand-enzyme complex.


Assuntos
Anti-Inflamatórios/química , Benzenoacetamidas/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/química , Óxidos S-Cíclicos/química , Inibidores da Fosfodiesterase 4/química , Pirimidinas/química , Animais , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/uso terapêutico , Benzenoacetamidas/metabolismo , Benzenoacetamidas/uso terapêutico , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Óxidos S-Cíclicos/metabolismo , Óxidos S-Cíclicos/uso terapêutico , Humanos , Lipopolissacarídeos/toxicidade , Pneumopatias/tratamento farmacológico , Pneumopatias/patologia , Camundongos , Inibidores da Fosfodiesterase 4/metabolismo , Inibidores da Fosfodiesterase 4/uso terapêutico , Ligação Proteica , Pirimidinas/metabolismo , Pirimidinas/uso terapêutico , Baço/citologia , Baço/metabolismo , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/metabolismo
14.
Oecologia ; 158(1): 23-34, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18709388

RESUMO

Polyphenism, which allows a single genotype to express multiple discrete phenotypes in response to environmental cues, is an adaptive trait in heterogeneous environments. Pond hydroperiod is an important ecological parameter affecting amphibian life history, and variation in local pond hydrology has been hypothesized to play a role in species divergence via changes in polyphenism. The eastern newt (Notophthalmus viridescens) expresses life cycle polyphenism. Larvae develop along three possible pathways: metamorphosis to aquatic lunged adult via a terrestrial juvenile (eft) stage, metamorphosis directly to an aquatic lunged adult, or maturation directly to an aquatic gilled adult without metamorphosis (i.e., paedomorphosis). Subspecies of N. viridescens vary in their polyphenic patterns, suggesting possible adaptation to different environments. However, no studies have experimentally tested how genetic and environmental components contribute to the observed differences among subspecies and whether such differences may facilitate divergence. We tested whether adaptation to local pond hydrology via polyphenic changes existed among subspecies by rearing larvae of three subspecies (N. v. dorsalis, N. v. louisianensis, and N. v. viridescens) along three hydroperiod regimes (short, long, and constant) in outdoor artificial ponds. We found that larval N. v. viridescens obligately metamorphosed to efts under all hydroperiods, whereas N. v. dorsalis and N. v. louisianensis exhibited plasticity: larvae metamorphosed to efts under drying conditions but metamorphosed directly to aquatic adults or became paedomorphic in constant water. Also, N. v. viridescens metamorphosed to efts faster and at a smaller body size than the other two subspecies. These data suggest that subspecies of N. viridescens are adapted to different pond hydroperiods, supporting the potential for polyphenism to facilitate divergence. Canalizing selection for certain alternative phenotypes within a single species in which other populations remain plastic may play an important role in the initiation of ecological divergence.


Assuntos
Adaptação Biológica , Metamorfose Biológica , Notophthalmus viridescens/crescimento & desenvolvimento , Fenótipo , Áreas Alagadas , Animais , Feminino , Masculino , Notophthalmus viridescens/genética
15.
Mol Divers ; 8(3): 209-18, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15384414

RESUMO

A practical high-throughput protein detection system is described, based on synthetic peptide arrays consisting of designed alpha-helical peptides, detected by fluorescence resonance energy transfer (FRET). Initially a model alpha-helical peptide known to interact with a structured protein, calmodulin, was selected to establish the strategy for high-throughput detection. In comparison to peptides with a single probe, a much higher FRET response has been observed with two fluorescent probes (7-diethylaminocoumarin-3-carboxylic acid and 5(6)-carboxy-fluorescein) at both termini of the synthetic peptides. To establish a reproducible high-throughput detection system, peptides were also immobilized onto a solid surface for detection of the target proteins. A small library of 112 different peptides was constructed, based on a model of the alpha-helical peptide with systematic replacement of residues carrying specific charges and/or hydrophobicities. The library was used to effectively characterize various proteins, giving their own 'protein fingerprint' patterns. The resulting 'protein fingerprints' correlate with the recognition properties of the proteins. The present microarray with designed synthetic peptides as the capturing agents is promising for the development of protein detection chips.


Assuntos
Peptídeos/química , Peptídeos/síntese química , Análise Serial de Proteínas , Sequência de Aminoácidos , Dicroísmo Circular , Transferência Ressonante de Energia de Fluorescência , Indicadores e Reagentes , Modelos Moleculares , Estrutura Secundária de Proteína , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
16.
Biopolymers ; 76(2): 129-39, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15054893

RESUMO

To realize a practical high-throughput protein-detection system, novel peptide arrays have been constructed using designed peptide libraries with loop, alpha-helix, or beta-strand structures. Here, we describe the overview of the reported designed peptide arrays with loop and alpha-helix structures and the new results of those with beta-strand structures. Initially, several model peptides known to interact with model structured proteins were selected to establish the present strategy for high-throughput detection of proteins. The fluorescent probes and suitable scaffolds of peptides were examined for the effective detection of proteins. The detection methods were established in solution and in an immobilized manner using the model systems. In the case of alpha-helix peptide, the response of a peptide with fluorescent resonance energy transfer between two probes at both termini was several times higher than that of a peptide with a single probe. In the cases of peptides with other structures, however, proteins were effectively detectable even by the fluorescent change of one probe. Furthermore, structurally focused libraries consisting of a total of ca. 250 different peptides based on the model peptides with secondary and/or tertiary structures were constructed with systematic replacement of residues. Using these libraries, various proteins were characterized effectively to give their own fluorescent "protein fingerprint" patterns. The resulting protein fingerprints correlated with the recognition properties of the proteins. These studies demonstrate that arrays with peptide libraries based on designed structures can be promising tools for detecting the target proteins. Designed synthetic peptides play roles as the capturing agents to be developed for practical protein chips.


Assuntos
Peptídeos/química , Análise Serial de Proteínas/métodos , Sequência de Aminoácidos , Corantes Fluorescentes/química , Biblioteca de Peptídeos , Mapeamento de Peptídeos/métodos , Estrutura Secundária de Proteína
17.
Chem Biol ; 10(1): 53-60, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12573698

RESUMO

Construction of a novel protein-detection system was carried out using a designed peptide library with fluorescent labels based on loop structures. As a basic model study, detection of alpha-amylase using fluorescent-labeled peptides derived from an active loop of tendamistat was examined. The detection methods for proteins with immobilized peptides as well as peptides in solution have been successfully established. Based on these results, a loop peptide library that has various turn sequences grafted on a stable loop structure has been constructed. Various proteins with recognition patterns corresponding, for instance, to "protein fingerprints" could be detected using an immobilized peptide library. The present results suggest that the system can be applied to the development of a peptide microarray that behaves as a protein chip.


Assuntos
Corantes Fluorescentes , Biblioteca de Peptídeos , Proteínas/análise , Sequência de Aminoácidos , Sítios de Ligação , Inibidores Enzimáticos/química , Métodos , Fragmentos de Peptídeos/química , Peptídeos/química , Estrutura Terciária de Proteína , Proteínas/antagonistas & inibidores , Proteínas/química , alfa-Amilases/análise , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química
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