Nature-derived compounds modulating Wnt/β-catenin pathway: a preventive and therapeutic opportunity in neoplastic diseases

Abstract The Wnt/β-catenin signaling is a conserved pathway that has a crucial role in embryonic and adult life. Dysregulation of the Wnt/β-catenin pathway has been associated with diseases including cancer, and components of the signaling have been proposed as innovative therapeutic targets, mainly for cancer therapy. The attention of the worldwide researchers paid to this issue is increasing, also in view of the therapeutic potential of these agents in diseases, such as Parkinson's disease (PD), for which no cure is existing today. Much evidence indicates that abnormal Wnt/β-catenin signaling is involved in tumor immunology and the targeting of Wnt/β-catenin pathway has been also proposed as an attractive strategy to potentiate cancer immunotherapy. During the last decade, several products, including naturally occurring dietary agents as well as a wide variety of products from plant sources, including curcunim, quercetin, berberin, and ginsenosides, have been identified as potent modulators of the Wnt/β-catenin signaling and have gained interest as promising candidates for the development of chemopreventive or therapeutic drugs for cancer. In this review we make an overview of the nature-derived compounds reported to have antitumor activity by modulating the Wnt/β-catenin signaling, also focusing on extraction methods, chemical features, and bio-activity assays used for the screening of these compounds

Percepções de pacientes sobre catarata

OBJECTIVE: To identify in adult patients suffering from cataract the perceptions regarding the disease and its surgical treatment. MATERIALS AND METHODS: An exploratory survey was conducted among adult patients suffering from cataract and participating in a large-scale cataract management program at the University of São Paulo General Hospital in 2004. The interviews were conducted by research assistants previously trained to pose questions and record answers. RESULTS: The sample consisted of 170 men and women (43.5% and 56.5%, respectively), aged between 40 and 88 years. Of the 170 participants, 43.5% were from the State of São Paulo, 14.7% from the State of Bahia, 12.4% from the State of Minas Gerais, 5.9% from the State of Pernambuco, 1.8% from other countries, and the remaining 21.7% were from other Brazilian states. Of those who were actively working (n = 87), 43.7% had an occupational level corresponding to nonspecialized manual labor, 27.6% were in specialized manual labor jobs, 25.3% had routine nonmanual occupations, 1.1% supervised manual labor, and 2.3% had low-ranking supervision or inspection jobs over nonmanual occupations. Of those who were not actively working (n = 82), 53.6% were retired, 45.2% were housewives, and 1.2% were unemployed. Concerning conceptions about cataract, 79.0% referred to it as "a small skin fold that gradually covers the eye" and 32.4% mentioned, in addition, other conceptions. Concerning the cause, of the alternatives presented to them, 80% reported aging, 47.1% blamed "overusing the eyes in the workplace or at home", 7.1% believed they had cataract due to some kind of "spell." Of the associated answers, 94.1% referred to "blurred vision" in people suffering from cataract, 72.4% thought the person may become blind, and 66.5% believed that the patients suffering from cataract are depressed because they cannot see. Regarding surgery, 28.8% were afraid of undergoing surgery; of those, 16.3% cited with the fear of dying during surgery, 55.1% thought they might become blind, 40.8% believed the surgery would be painful, and 8.2% followed religious practices that do not permit surgery. CONCLUSION: Some misconceptions were identified, and the fear of blindness was the most mentioned reason for not seeking cataract surgery, which indicates the need for orientation.OBJETIVO: Identificar percepções de adultos portadores de catarata em relação à doença e ao tratamento cirúrgico. MATERIAIS E MÉTODOS: Foi realizada uma pesquisa exploratória entre pacientes adultos portadores de catarata presentes em mutirão em hospital universitário no ano de 2004. Auxiliares de pesquisa previamente treinados para formulação das questões e registros das respostas, encarregaram-se das entrevistas. RESULTADOS: A amostra foi composta por 170 sujeitos de ambos os sexos (43,5% do sexo masculino e 56,5% do sexo feminino) com idade entre 40 e 88 anos. Dos 170 participantes, 43,5% eram nascidos no estado de São Paulo, 14,7% na Bahia, 12,4% em Minas Gerais, 1,8% nasceram em outros paises e os demais sujeitos, em outros estados brasileiros.Da população ativa no mercado de trabalho (n=87), encontravam-se em nível de ocupação manual não especializada 43,7%; ocupação manual especializada 27,6%; ocupação de rotina não manual 25,3%; supervisão de trabalho manual 1,1%; posição baixa de supervisão ou inspeção , considerando ocupações não manuais,2,3 %. Entre a população inativa no mercado de trabalho (n=82), 53,6% eram aposentados, 45,2% donas de casa e 1,2% desempregados. Em relação a concepção sobre catarata, 79,0% referiram ser uma "pelezinha que vai cobrindo os olhos" e 32,4% além da "pelezinha", mencionaram outras concepções. Em relação a causa , entre as opções fornecidas, 80% relacionam a velhice; 47,1% "por usar muito as vistas no serviço ou em casa"; 7,1% acreditam que tem catarata devido a "mau olhado". Dentre as respostas associadas, 94,1% referiram que a "visão fica embaçada" na pessoa que tem catarata, 72,4% acham que a pessoa pode ficar cega e 66,5% acham que os portadores de catarata ficam com depressão por não enxergarem. Vinte e oito por cento tem medo de se submeter a cirurgia, desses, 16,3% atribuem ao fato de poderem morrer na cirurgia; 55,1% acham que podem ficar cego; 40,8% crêem que a cirurgia dói e 8,2% tem medo de operar pois a religião não permite. CONCLUSÃO: Foram evidenciados alguns conhecimentos incorretos, o medo de ficar cego se fez presente entre as razões para não operar a catarata, indicando necessidade de provimento de orientação

Design of epidermal growth factor immobilization on 3D biocompatible scaffolds to promote tissue repair and regeneration

Exogenous application of human epidermal growth factor (hEGF) stimulates epidermal wound healing. The aim of this study was to develop bioconjugates based on hEGF mimicking the protein in its native state and thus suitable for tissue engineering applications, in particular for treating skin-related disorders as burns. Ribonuclease A (RNase A) was used to investigate a number of different activated-agarose carriers: cyanogen bromide (CNBr)-activated-agarose and glyoxyl-agarose showed to preserve the appropriate orientation of the protein for receptor binding. EGF was immobilized on these carriers and immobilization yield was evaluated (100% and 12%, respectively). A peptide mapping of unbound protein regions was carried out by LC–MS to take evidence of the residues involved in the immobilization and, consequently, the flexibility and surface accessibility of immobilized EGF. To assess cell proliferative activities, 10, 25, 50, and 100 ng/mL of each immobilized EGF sample were seeded on fibroblast cells and incubated for 24, 48 and 72 h. The immobilized growth factor showed significantly high cell proliferative activity at 50 and 100 ng/mL compared to control and soluble EGF. Although both of the immobilized samples show dose-dependency when seeded with high number of fibroblast cells, CNBr-agarose-EGF showed a significantly high activity at 100 ng/mL and 72 h incubation, compared to glyoxyl-agarose-EGF

[reasons For Cataract Surgery Cancellation].

To study the reasons for cancelling cataract surgeries, and to suggest actions to improve the efficiency of patient care. A cross-sectional study was carried out in a university hospital's ophthalmology clinic of the state of São Paulo, Brazil. Two hundred subjects were randomly selected. The mean age was 68+/- 11.4 years old. The reasons for cancelling surgery were: unpropitious clinical condition (23.1%); tight schedule (35.9%); and patient non-attendance (41%). Most of the reasons related to social issues and the hospital's administrative aspects.35487-

Surface Plasmon Resonance as a Tool for Ligand Binding Investigation of Engineered GPR17 Receptor, a G Protein Coupled Receptor Involved in Myelination

The aim of this study was to investigate the potential of surface plasmon resonance (SPR) spectroscopy for the measurement of real-time ligand-binding affinities and kinetic parameters for GPR17, a G protein-coupled receptor (GPCR) of major interest in medicinal chemistry as potential target in demyelinating diseases. The receptor was directly captured, in a single-step, from solubilized membrane extracts on the sensor chip through a covalently bound anti-6x-His-antibody and retained its ligand binding activity for over 24h. Furthermore, our experimental setup made possible, after a mild regeneration step, to remove the bound receptor without damaging the antibody, and thus to reuse many times the same chip. Two engineered variants of GPR17, designed for crystallographic studies, were expressed in insect cells, extracted from crude membranes and analyzed for their binding with two high affinity ligands: the antagonist Cangrelor and the agonist Asinex 1. The calculated kinetic parameters and binding constants of ligands were in good agreement with those reported from activity assays and highlighted a possible functional role of the N-terminal residues of the receptor in ligand recognition and binding. Validation of SPR results was obtained by docking and molecular dynamics of GPR17-ligands interactions and by functional in vitro studies. The latter allowed us to confirm that Asinex 1 behaves as GPR17 receptor agonist, inhibits forskolin-stimulated adenylyl cyclase pathway and promotes oligodendrocyte precursor cell maturation and myelinating ability

Clinical glaucoma treatment at a university hospital: monthly cost and financial impact

Purpose: To verify the social characteristics and the impact of glaucoma treatment on the familial income of patients followed at a university hospital. Methods: One hundred and forty six glaucomatous patients were interviewed at the Hospital das Clínicas da Universidade de Campinas to evaluate their social economic profile. The questionnaire investigated the occupation, the individual and familial income, as well as the type and frequency of the antiglaucomatous drugs used by each patient. Knowing the monthly cost of antiglaucomatous drugs available in Brazil, we were able to calculate the monthly cost of glaucoma treatment and the percentage of committed familial income. Results: The mean monthly cost of glaucoma treatment was 36.09 ± 31.99 reais, which corresponded to 15.5% of the familial income. Thirty-six (24%) patients had 25 percent or more of the familial income spent on their treatment. Sixty-six (45.2%) patients had difficulty in buying their medications. Factors associated with this difficulty included low familial income (p=0.0001), and high percentage of the income used to buy the drugs (p=0.0002). Conclusion: The cost of glaucoma treatment is high compared to the income of patients treated at a public institution. This population has a low familial income, of which a high percentage is required to acquire antiglaucoma medications. We suggest that these patients may be at risk for low compliance due to economical limitations.Objetivo: Verificar características sociais e o impacto do custo do tratamento antiglaucomatoso na renda familiar entre pacientes do Serviço de Oftalmologia de hospital universitário. Métodos: Realizou-se estudo transversal entre 146 pacientes do Setor de Glaucoma do Hospital das Clínicas da Universidade Estadual de Campinas (UNICAMP), aplicando-se um questionário por entrevista. Foram investigadas as variáveis: escolaridade, exercício de atividade profissional, renda própria e familiar, quantidade e tipo de medicações e tempo de tratamento antiglaucomatoso. A partir do custo mensal de medicações antiglaucomatosas disponíveis no Brasil e dos dados obtidos na entrevista, calculou-se o custo médio mensal do tratamento clínico e a porcentagem da renda familiar destinada à aquisição desses medicamentos. Além disto, investigaram-se fatores associados à dificuldade de aquisição da medicação. Resultados: O custo mensal médio do tratamento antiglaucomatoso foi de 36,09 ± 31,99 reais, o que correspondeu a 15,5% da renda familiar média. Aproximadamente 24,0% dos pacientes tiveram 25% ou mais de sua renda comprometida com o tratamento e 45,2% relataram dificuldade de adquirir a medicação em algum momento do tratamento. Os principais fatores associados à dificuldade de compra da medicação foram a reduzida renda familiar (p=0,0001) e a expressiva parcela da renda familiar destinada ao tratamento (p=0,0002). Conclusões: O tratamento do glaucoma apresentou custo elevado em relação à renda familiar da amostra. Evidenciou-se tratar de pacientes de baixa renda, destinada em boa parte ao tratamento do glaucoma. Admite-se que possam apresentar maior risco de baixa adesão ao tratamento antiglaucomatoso por dificuldades para adquirirem a medicação.29930

The Genome of Nectria haematococca: Contribution of Supernumerary Chromosomes to Gene Expansion

The ascomycetous fungus Nectria haematococca, (asexual name Fusarium solani), is a member of a group of >50 species known as the “Fusarium solani species complex”. Members of this complex have diverse biological properties including the ability to cause disease on >100 genera of plants and opportunistic infections in humans. The current research analyzed the most extensively studied member of this complex, N. haematococca mating population VI (MPVI). Several genes controlling the ability of individual isolates of this species to colonize specific habitats are located on supernumerary chromosomes. Optical mapping revealed that the sequenced isolate has 17 chromosomes ranging from 530 kb to 6.52 Mb and that the physical size of the genome, 54.43 Mb, and the number of predicted genes, 15,707, are among the largest reported for ascomycetes. Two classes of genes have contributed to gene expansion: specific genes that are not found in other fungi including its closest sequenced relative, Fusarium graminearum; and genes that commonly occur as single copies in other fungi but are present as multiple copies in N. haematococca MPVI. Some of these additional genes appear to have resulted from gene duplication events, while others may have been acquired through horizontal gene transfer. The supernumerary nature of three chromosomes, 14, 15, and 17, was confirmed by their absence in pulsed field gel electrophoresis experiments of some isolates and by demonstrating that these isolates lacked chromosome-specific sequences found on the ends of these chromosomes. These supernumerary chromosomes contain more repeat sequences, are enriched in unique and duplicated genes, and have a lower G+C content in comparison to the other chromosomes. Although the origin(s) of the extra genes and the supernumerary chromosomes is not known, the gene expansion and its large genome size are consistent with this species' diverse range of habitats. Furthermore, the presence of unique genes on supernumerary chromosomes might account for individual isolates having different environmental niches

Insertion of Horizontally Transferred Genes within Conserved Syntenic Regions of Yeast Genomes

Horizontal gene transfer has been occasionally mentioned in eukaryotic genomes, but such events appear much less numerous than in prokaryotes, where they play important functional and evolutionary roles. In yeasts, few independent cases have been described, some of which corresponding to major metabolic functions, but no systematic screening of horizontally transferred genes has been attempted so far. Taking advantage of the synteny conservation among five newly sequenced and annotated genomes of Saccharomycetaceae, we carried out a systematic search for HGT candidates amidst genes present in only one species within conserved synteny blocks. Out of 255 species-specific genes, we discovered 11 candidates for HGT, based on their similarity with bacterial proteins and on reconstructed phylogenies. This corresponds to a minimum of six transfer events because some horizontally acquired genes appear to rapidly duplicate in yeast genomes (e.g. YwqG genes in Kluyveromyces thermotolerans and serine recombinase genes of the IS607 family in Saccharomyces kluyveri). We show that the resulting copies are submitted to a strong functional selective pressure. The mechanisms of DNA transfer and integration are discussed, in relation with the generally small size of HGT candidates. Our results on a limited set of species expand by 50% the number of previously published HGT cases in hemiascomycetous yeasts, suggesting that this type of event is more frequent than usually thought. Our restrictive method does not exclude the possibility that additional HGT events exist. Actually, ancestral events common to several yeast species must have been overlooked, and the absence of homologs in present databases leaves open the question of the origin of the 244 remaining species-specific genes inserted within conserved synteny blocks