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1.
Glycoconj J ; 37(2): 263-275, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32062822

RESUMO

The complex enzyme network responsible for glycan synthesis suffers significant changes during the first steps of tumor development, leading to the early formation of tumor-associated glycan signatures. Among the glycosylation pathways, changes in fucosylation emerged as one of most important features in cancer. Αlpha-1,3/4-fucosyltransferase (FUT3) has been linked to pro-tumor and anti-tumor pathways depending on the cancer type. The present study aimed to understand the gene and protein expression profiles of FUT3 in three different and independent cohorts composed by invasive breast cancer patients: Local Brazilian population, METABRIC and TCGA. FUT3 transcripts and protein were measured in the Brazilian population by real-time PCR and Western blotting, respectively. Clinical records and FUT3 levels from public METABRIC and TCGA cohorts were accessed through CBioPortal database. FUT3 expression was analyzed in each cohort using the appropriated statistic tools. Survival meta-analysis in triple negative patients was performed using five independent cohorts including GSE41119, GSE47994 and GSE86945, data obtained from GEO repository available at NCBI database, and METABRIC and TCGA. Our analysis showed that high FUT3 levels were consistently associated to reduced invasive breast cancer patients overall survival. This finding is particularly significant in triple negative patients. These results together with the previously knowledge regarding the involvement of FUT3 in pro-tumor and anti-tumor mechanisms led us to purpose a model for FUT3 expression regulation throughout breast cancer establishment and progression.


Assuntos
Biomarcadores Tumorais/genética , Fucosiltransferases/genética , Neoplasias de Mama Triplo Negativas/genética , Biomarcadores Tumorais/metabolismo , Feminino , Fucosiltransferases/metabolismo , Humanos , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sobrevida , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
2.
Mol Biol Rep ; 46(3): 3531-3536, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30929162

RESUMO

FUT3 gene is responsible for encode an homonymous α1,3/4-fucosyltransferase involved in the synthesis of sialyl-Lewis antigens. FUT3-fucosylated glycoconjugates play key roles in pathways involved in tumor biology and metastasis, such as cellular ligation to E-selectins, TGF-ß-induced epithelial-mesenchymal transition, NK cell-mediated tumor cytotoxicity and apoptosis. Tumor-associated FUT3 promoter polymorphism rs2306969 (-6951 C> T, position related to the gene's translation start site) has been linked to breast, ovarian and intestinal gastric cancer. Although non-coding polymorphisms accounts for the majority of variations founded in breast cancer, their functional roles are still poorly understood. This study aimed to investigate the impact of different alleles for this variation in FUT3 expression of invasive breast tumors. A luciferase reporter assay was performed using two breast tumor cell lines to evaluate respectively the impact of FUT3 rs2306969 (-6951 CC) and (-6951 TT) on protein expression. Gene and protein expressions were also measured in twenty-nine fresh biopsies of invasive breast tumors. Rs2306969 did not significantly influence FUT3 expression in both used systems. However, this study is defiant since the biological role of this polymorphism in breast cancer and other tumor types could be linked to cis/trans modulation of other genes, respond to different environmental stimuli or impact gene expression only in association with other variations. Rs2306969 did not modulate FUT3 expression in breast tumors under non-stimulated conditions. Nevertheless, our study contributes to the notably challenging task that is to understand how non-coding polymorphisms can drive the overall risk in cancer development.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Fucosiltransferases/genética , Alelos , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Feminino , Fucosiltransferases/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Humanos , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , Fator de Crescimento Transformador beta/genética
3.
Anal Biochem ; 548: 91-95, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29458035

RESUMO

In order to characterize the affinity between specific carbohydrate-binding proteins such as lectins, a model is proposed to study these interactions using a polysaccharide membrane to simulate such adsorption. Here, lectin-carbohydrate interactions were chemiluminescently investigated using lectins conjugated to acridinium ester (AE) and polysaccharides composed of their respective specific carbohydrates. The lectin-AE conjugates were incubated with discs (0.0314-0.6358 cm2) of phytagel, chitosan and carrageenan. The complex formation chemiluminescently detected followed the Langmuir isotherm from which constants were estimated. The association constant (Ka) and maximum binding sites on the membranes were 2.4 × 10-7 M-1 ±â€¯0.8 × 10-7 M-1 and 1.3 × 10-3 mol. mg-1 ± 0.3 × 10-3 mol. mg-1 (Con A); 0.9 × 10-6 M-1 ±â€¯0.4 × 10-6 M-1 and 0.021 × 10-3 mol. mg-1 ± 0.003 × 10-3 mol. mg-1 (WGA) and 2.0 × 10-6 M-1 ±â€¯0.9 × 10-6 M-1 and 0.069 × 10-3 mol. mg-1 ± 0.010 × 10-3 mol. mg-1 (PNA). The proposed model might be useful to study binding affinity and estimate the amount of binding not limited by the sugar content in the membrane.


Assuntos
Quitosana/análise , Chondrus/química , Medições Luminescentes/métodos , Membranas Artificiais , Lectinas de Plantas/análise , Lectinas de Plantas/química
4.
Biochim Biophys Acta ; 1840(6): 1902-12, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24361617

RESUMO

BACKGROUND: Our previous study demonstrated that essential fatty acid (EFA) dietary restriction over two generations induced midbrain dopaminergic cell loss and oxidative stress in the substantia nigra (SN) but not in the striatum of young rats. In the present study we hypothesized that omega-3 deficiency until adulthood would reduce striatum's resilience, increase nitric oxide (NO) levels and the number of BDNF-expressing neurons, both potential mechanisms involved in SN neurodegeneration. METHODS: Second generation rats were raised from gestation on control or EFA-restricted diets until young or adulthood. Lipoperoxidation, NO content, total superoxide dismutase (t-SOD) and catalase enzymatic activities were assessed in the SN and striatum. The number of tyrosine hydroxylase (TH)- and BDNF-expressing neurons was analyzed in the SN. RESULTS: Increased NO levels were observed in the striatum of both young and adult EFA-deficient animals but not in the SN, despite a similar omega-3 depletion (~65%) in these regions. Increased lipoperoxidation and decreased catalase activity were found in both regions, while lower tSOD activity was observed only in the striatum. Fewer TH- (~40%) and BDNF-positive cells (~20%) were detected at the SN compared to the control. CONCLUSION: The present findings demonstrate a differential effect of omega-3 deficiency on NO production in the rat's nigrostriatal system. Prolonging omega-3 depletion until adulthood impaired striatum's anti-oxidant resources and BDNF distribution in the SN, worsening dopaminergic cell degeneration. GENERAL SIGNIFICANCE: Omega-3 deficiency can reduce the nigrostriatal system's ability to maintain homeostasis under oxidative conditions, which may enhance the risk of Parkinson's disease.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/fisiologia , Ácidos Graxos Ômega-3/fisiologia , Óxido Nítrico/biossíntese , Doença de Parkinson/etiologia , Substância Negra/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/análise , Catalase/metabolismo , Feminino , Peroxidação de Lipídeos , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Tirosina 3-Mono-Oxigenase/análise
5.
Exp Mol Pathol ; 99(3): 409-15, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26321244

RESUMO

Fucosylated glycans synthesized by α1,3/4-fucosyltransferase (FUT3) enzyme play an important role in breast cancer prognosis and metastasis, being involved in the binding of circulating tumor cells to the endothelium and being related to tumor stage, metastatic potential and chemoresistance. Despite the pro-tumor action of this enzyme, studies have demonstrated its role in natural killer-induced cytotoxicity through the recognition of sialyl Lewis X by C-type lectin receptors and through extrinsic apoptosis pathway triggered by Apo2L-TRAIL. This study aimed to investigate the expression pattern of FUT3 in invasive breast carcinoma (IDC) from patients of Pernambuco state, Northeast of Brazil, and genotype FUT3 promoter region to identify possible SNPs that could be associated with variations in FUT3 expression. Immunohistochemistry assay was used to access the FUT3 expression in normal (n=11) and tumor tissues (n=85). DNA sequencing was performed to genotype the FUT3 promoter region in patients with IDC (n=109) and healthy controls (n=110). Our results demonstrated that the absence of FUT3 enzyme is related to breast's IDC. The non-expression of FUT3 was more frequent in larger lesions and also in HER2 negative IDC tumors. Genomic analysis showed that two variations localized in FUT3 promoter region are possibly associated with IDC. Our results suggest that minor allele T of SNP rs73920070 (-6933 C>T) confers protection whereas minor allele T of SNP rs2306969 (-6951 C>T) triggers to susceptibility to IDC in the population of Pernambuco state, Northeast of Brazil.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patologia , Fucosiltransferases/genética , Regulação Neoplásica da Expressão Gênica/genética , Regiões Promotoras Genéticas , Brasil , Feminino , Fucosiltransferases/metabolismo , Humanos , Imuno-Histoquímica/métodos , Antígenos CD15/metabolismo
6.
Int J Mol Sci ; 16(6): 13023-42, 2015 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-26068233

RESUMO

In this work, the acridine nucleus was used as a lead-compound for structural modification by adding different substituted thiosemicarbazide moieties. Eight new (Z)-2-(acridin-9-ylmethylene)-N-phenylhydrazinecarbothioamide derivatives (3a-h) were synthesized, their antiproliferative activities were evaluated, and DNA binding properties were performed with calf thymus DNA (ctDNA) by electronic absorption and fluorescence spectroscopies. Both hyperchromic and hypochromic effects, as well as red or blue shifts were demonstrated by addition of ctDNA to the derivatives. The calculated binding constants ranged from 1.74 × 10(4) to 1.0 × 10(6) M(-1) and quenching constants from -0.2 × 10(4) to 2.18 × 10(4) M(-1) indicating high affinity to ctDNA base pairs. The most efficient compound in binding to ctDNA in vitro was (Z)-2-(acridin-9-ylmethylene)-N- (4-chlorophenyl) hydrazinecarbothioamide (3f), while the most active compound in antiproliferative assay was (Z)-2-(acridin-9-ylmethylene)-N-phenylhydrazinecarbothioamide (3a). There was no correlation between DNA-binding and in vitro antiproliferative activity, but the results suggest that DNA binding can be involved in the biological activity mechanism. This study may guide the choice of the size and shape of the intercalating part of the ligand and the strategic selection of substituents that increase DNA-binding or antiproliferative properties.


Assuntos
Acridinas/química , Antineoplásicos/síntese química , Proliferação de Células/efeitos dos fármacos , Tiossemicarbazonas/química , Antineoplásicos/farmacologia , DNA/química , Células MCF-7
7.
Molecules ; 20(3): 3776-82, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25723851

RESUMO

Cryptococcus neoformans var. grubii is considered to be the major cause of cryptococcosis in immunosuppressed patients. Understanding cell wall glycoproteins using lectins is of medical interest and can contribute to specific therapy. The aim of this study was to evaluate the carbohydrates on the cell wall of Cryptococcus neoformans var. grubii clinical isolates, using a fluorescein isothiocyanate-lectin binding protocol. Thirty yeast strains stocked in the culture collection were cultivated for 2 days at 30 °C with shaking. Cells were obtained by centrifugation, washed in phosphate-buffered saline, and a suspension of 107 cells/mL was obtained. To determine the binding profile of lectins, concanavalin A (Con A), wheat germ agglutinin (WGA), Ulex europaeus agglutinin I (UEA-I), and peanut agglutinin (PNA) conjugated to fluorescein were used. All the tested clinical isolates of Cryptococcus neoformans var. grubii were intensely stained by WGA, moderately stained by Con A, and weakly stained by PNA and UEA-I. Thus, Cryptococcus can be detected in clinical specimens such as blood and cerebrospinal fluid using the fluorescent lectin WGA, which may be considered as an option for detection in cases of suspected cryptococcosis with low laboratory sensitivity. Future applications may be developed using this basic tool.


Assuntos
Carboidratos , Parede Celular/metabolismo , Concanavalina A/metabolismo , Criptococose/metabolismo , Cryptococcus neoformans/isolamento & purificação , Cryptococcus neoformans/metabolismo , Lectinas/metabolismo , Criptococose/microbiologia , Criptococose/patologia , Humanos
8.
Molecules ; 18(12): 15035-50, 2013 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-24322489

RESUMO

Thiazacridine and imidazacridine derivatives have shown promising results as tumors suppressors in some cancer cell lines. For a better understanding of the mechanism of action of these compounds, binding studies of 5-acridin-9-ylmethylidene-3-amino-2-thioxo-thiazolidin-4-one, 5-acridin-9-ylmethylidene-2-thioxo-thiazolidin-4-one, 5-acridin-9-ylmethylidene-2-thioxo-imidazolidin-4-one and 3-acridin-9-ylmethyl-thiazolidin-2,4-dione with calf thymus DNA (ctDNA) by electronic absorption and fluorescence spectroscopy and circular dichroism spectroscopy were performed. The binding constants ranged from 1.46 × 10(4) to 6.01 × 10(4) M(-1). UV-Vis, fluorescence and circular dichroism measurements indicated that the compounds interact effectively with ctDNA, both by intercalation or external binding. They demonstrated inhibitory activities to human topoisomerase I, except for 5-acridin-9-ylmethylidene-2-thioxo-1,3-thiazolidin-4-one. These results provide insight into the DNA binding mechanism of imidazacridines and thiazacridines.


Assuntos
Acridinas/síntese química , Acridinas/farmacologia , Inibidores da Topoisomerase I/síntese química , Inibidores da Topoisomerase I/farmacologia , Acridinas/metabolismo , Antineoplásicos/química , Antineoplásicos/farmacologia , Dicroísmo Circular , DNA/química , DNA/metabolismo , DNA Topoisomerases Tipo I/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Estrutura Molecular , Inibidores da Topoisomerase I/metabolismo
9.
Med Mol Morphol ; 46(2): 92-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23381603

RESUMO

Breast carcinoma is one of the most common neoplasia and the first cause of women cancer related deaths worldwide. In the past few years with diagnostic increment, the number of patients diagnosed with ductal carcinoma in situ (DCIS) increased considerably and opened up new ways in research and new dilemmas in diagnostic and clinical practice. This work aimed to evaluate differences in Galectin-1 and Galectin-3 expression and lectins ligands profile on DCIS cells in hypoxic microenvironment. Lectin histochemistry and immunohistochemistry were performed with Concanavalin A, Wheat Germ Agglutinin, Peanut Agglutinin and Ulex europaeus Agglutinin lectins and with anti-Galectin-1 and anti-Galectin-3 antibodies. Lectin ligands were more recognized in hypoxic lesions by Concanavalin A (p = 0.0019), Wheat Germ Agglutinin (p < 0.001) and Ulex europaeus Agglutinin (p = 0.0014), but not by Peanut Agglutinin (p = 0.5779) when compared to non-hypoxic. Galectin-1 was not observed in all cases analyzed on both groups, differing from Galectin-3 that was overexpressed on cytoplasm of DCIS hypoxic group in relation to control group (p = 0.031). As far as we are concerned, this is the first paper that describes glycobiological alterations in breast cancer hypoxic environment in vivo that could be used to validate in vitro models on this aspect. Moreover, comedogenic/necrotic carcinomas were usually associated with poor-prognostic than others, and our results show that glycosylation may play an important role in this event.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Intraductal não Infiltrante/metabolismo , Hipóxia/metabolismo , Microambiente Tumoral/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Feminino , Galectina 1/biossíntese , Galectina 3/biossíntese , Regulação Neoplásica da Expressão Gênica , Humanos , Hipóxia/patologia , Imuno-Histoquímica , Lectinas/metabolismo
10.
Mycoses ; 54(6): e789-94, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21615541

RESUMO

Various researchers have concluded that lectins are useful reagents for the study of fungal cell wall surface glycoconjugates. In this study, we evaluated the expression of N-acetyl-D-glucosamine, L-fucose, D-galactose and glucose/mannose on the cell wall surface of Trichophyton tonsurans and other keratinophilic filamentous fungi, using a simple lectin-binding protocol. The fungal cultures used were isolated from soils obtained from public parks by the hair-bait technique. The lectin assays used concanavalin A (Con A), wheat germ agglutinin (WGA), Ulex europeus agglutinin I (UEA-I) and peanut agglutinin (PNA), all conjugated with horseradish peroxidase. Adhesive tape was placed sticky-side down over the fungal colony, gently pressed and then removed. The fungal-tape samples were incubated with the lectin for 1 h at 4 °C. Lectin binding was visualised using 3,3-diaminobendizine (DAB) and hydrogen peroxidase. There was a high expression of N-acetyl-D-glucosamine on the cell wall surface of all fungi species tested, whereas the expression of L-fucose, D-galactose and glucose/mannose demonstrated inter-specific variations. The lectin-binding assay presented in this article eliminates many of the laborious steps involved in other protocols. The amount and quality of the mycelium and spores immobilised by the adhesive tapes were suitable for obtaining the carbohydrate profile in glycoconjugates of the cell wall surface of filamentous fungi.


Assuntos
Parede Celular/química , Fungos/química , Glicoconjugados/análise , Lectinas/metabolismo , Micologia/métodos , Ligação Proteica , Microbiologia do Solo
11.
Mycopathologia ; 171(6): 403-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21365320

RESUMO

This work was based on the analysis of digital images of histochemical profile from subcutaneous lesions in sporotrichosis (ST) and chromoblastomycosis (CM) patients. An additional aim was the detection of carbohydrate expression using lectin histochemical analysis of the different carbohydrates in the fungal cell wall from four different species (Sporothrix schenckii, Fonsecaea pedrosoi, Phialophora verrucosa, and Cladophialophora carrionii) associated with diseases mentioned earlier. Slides from tissue biopsies from ST and CM positive patients (n=10, each) were stained according to routine techniques. Slides were incubated with 25 µg/ml of Con A lectins and WGA conjugated to peroxidase. Digital image analysis was carried out in a workstation using OPTIMAS™ software system. Routine histochemistry results indicated that there is significantly higher collagen deposition and elastic fibers in ST characteristic lesions compared with that found in CM cases. The ST interstitial fibrosis area was larger than in CM lesions. Comparative lectin binding showed a positive and intense lectin staining pattern in the cell wall of S. schenckii, suggesting a higher expression of glucose/mannose and N-acetyl glucosamine in their cell surface as evidenced by Con A and WGA, respectively. However, these lectins were not effective to recognize some carbohydrates moieties in the F. pedrosoi, P. verrucosa, and C. carrionii. Such findings contribute to additional information about specific recognition processes between fungal parasites and their host cell targets may be mediated by the interaction of carbohydrate-binding proteins, such as lectins, on the surface of one type of cell that combine with complementary sugars on the surface of another cells into fibro-connective tissues associated with lesions.


Assuntos
Carboidratos/biossíntese , Cromoblastomicose/microbiologia , Fungos Mitospóricos/metabolismo , Esporotricose/microbiologia , Adulto , Parede Celular/metabolismo , Cromoblastomicose/patologia , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Feminino , Histocitoquímica , Humanos , Processamento de Imagem Assistida por Computador/métodos , Lectinas/química , Masculino , Phialophora/metabolismo , Sporothrix/metabolismo , Esporotricose/patologia
12.
Birth Defects Res B Dev Reprod Toxicol ; 89(2): 164-70, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20437476

RESUMO

BACKGROUND: Omega-6 fatty acids are important to fetal development. However, during gestation/lactation, these fatty acids may contribute toward the development of fat tissue. Omega-9 fatty acids are associated with a reduction in serum lipids and protection from liver disease. OBJECTIVES: The present study investigated the effect of the maternal intake of omega-6 and omega-9 in hypercholesterolemic mothers on the liver of the offspring. METHODS: LDL receptor-deficient mice were fed a diet rich in either omega-6 (E6D) or omega-9 (E9D) for 45 days prior to mating and until the birth of the offspring, evaluating the effect on the offspring liver in comparison to a standard diet (STD). RESULTS: Mothers fed with the E6D experienced an increase in total cholesterol (TC) and the offspring exhibited an increase in TC, hepatic triglycerides (TG), and CC-chemokine ligand (CCL)2/monocyte chemoattractant protein (MCP)-1 as well as a reduction in HDL. Histological analysis on this group revealed steatosis, leukocyte infiltrate, and increased CCL2/MCP-1 expression. The ultrastructural analysis revealed hepatocytes with lipid droplets and myofibroblasts. The offspring of mothers fed the standard diet exhibited low serum TC, but microvesicular steatosis was observed. The offspring of mothers fed the E9D exhibited lower serum and hepatic TG as well as higher LDL in comparison to the other diets. The histological analyses revealed lower steatosis and leukocyte infiltrate. CONCLUSIONS: The findings suggest that hypercholesterolemic mothers with a diet rich in omega-6 fatty acids predispose their offspring to steatohepatitis, whereas a diet rich in omega-9 has a protective effect.


Assuntos
Embrião de Mamíferos/efeitos dos fármacos , Ácidos Graxos Monoinsaturados/administração & dosagem , Ácidos Graxos Ômega-6/administração & dosagem , Fígado/efeitos dos fármacos , Exposição Materna/efeitos adversos , Receptores de LDL/metabolismo , Ração Animal , Animais , Animais Recém-Nascidos , Embrião de Mamíferos/embriologia , Desenvolvimento Embrionário/efeitos dos fármacos , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/patologia , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/ultraestrutura , Hipercolesterolemia/induzido quimicamente , Hipercolesterolemia/congênito , Hipercolesterolemia/metabolismo , Fígado/embriologia , Fígado/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Gravidez , Receptores de LDL/deficiência
13.
Pathol Oncol Res ; 25(2): 759-768, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30689164

RESUMO

Mammary carcinoma is the most common malignant tumor in women, and it is the leading cause of mortality. In tumor context, glycosylation promotes post translational modifications necessary for cell progression, emerging as a relevant tumor hallmarker. This study aimed to analyze the association between polypeptide N-acetylgalactosaminyltransferase-6 (ppGalNAc-T6), -T8, N-acetylglucosaminyltransferase III (GnT-III) expression, Phaseolus vulgaris-leucoagglutinin (PHA-L), wheat germ agglutinin (WGA) and peanut agglutinin (PNA) staining with clinic-histopathological factors from patients with pure ductal carcinoma in situ (DCIS) and DCIS with invasive ductal carcinoma (DCIS-IDC) of breast. Formalin-fixed and paraffin-embedded samples (n = 109) were analyzed. In pure DCIS samples GnT-III was over-expressed in comedo lesions (p = 0.007). In DCIS-IDC, GnT-III expression was associated with high nuclear grade tumors (p = 0.039) while the presence of PHA-L and WGA were inversely related to HER-2 expression (p = 0.001; p = 0.036, respectively). These findings pointed to possible involvement of GnT-III, ppGalNAc-T8, L-PHA and WGA as probes in prognostic evaluation of DCIS.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , N-Acetilglucosaminiltransferases/metabolismo , Adulto , Neoplasias da Mama/enzimologia , Carcinoma Ductal de Mama/enzimologia , Carcinoma Intraductal não Infiltrante/enzimologia , Feminino , Humanos , Pessoa de Meia-Idade , N-Acetilglucosaminiltransferases/análise
14.
Biomed Pharmacother ; 96: 1538-1556, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29174576

RESUMO

DNA is considered one of the most promising targets of molecules with anticancer activity potential. Its key role in various cell division mechanisms, which commands the intense multiplication of tumor cells, is considered in studies with compounds whose mechanisms of action suggest likeliness of interaction. In addition, inhibition of enzymes that actively participate in biological functions of cells such as Topoisomerase, is seen as a primary factor for conducting several events that result in cell death. Discovery of new anticancer chemotherapeutical capable of interacting with DNA and inhibiting Topoisomerase enzymes is highlighted in anticancer research. The present review aims at showing through distinct biological tests the performance of different candidates to anticancer drugs and their respective chemical modifications, which are crucial and/or determinant for DNA affinity and inhibition of important enzymes in cells' vital processe to either separately or synergistically optimize anticancer activity.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , DNA Topoisomerases/metabolismo , DNA/metabolismo , Inibidores da Topoisomerase/farmacologia , Inibidores da Topoisomerase/uso terapêutico , Animais , Desenho de Fármacos , Humanos
15.
Microsc Res Tech ; 80(6): 608-614, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28110504

RESUMO

Fluorescent compounds have been widely used for biomolecule labeling in cytochemistry and histochemistry analysis. Here, it is described the optical properties of dimethyl 2-[(acridin-9-yl)methylidene]-malonate (LPSF/IP-81), an acridine derivative. This compound was conjugated to Concanavalin A (Con A) lectin and applied as sugar probe in lectin histochemistry. Evaluation of luminescent properties showed that LPSF/IP-81 is photoluminescent with excitation at 360 nm and emission at 428 nm. Con A hemagglutinating activity and LPSF/IP81 photoluminescence were unaltered after conjugation. Circular dichroism of Con A-LPSF/IP81 conjugate showed the maintenance of the Con A structure. Lectin histochemistry with Con A-LPSF/IP81 conjugate demonstrated different pattern recognition studying normal, fibroadenoma, and invasive ductal carcinoma of human breast. These findings indicate that LPSF/IP-81 can be proposed as an alternative probe for histochemical analysis.


Assuntos
Acridinas/química , Neoplasias da Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Concanavalina A/química , Fibroadenoma/diagnóstico por imagem , Corantes Fluorescentes/química , Lectinas/análise , Malonatos/química , Mama/diagnóstico por imagem , Dicroísmo Circular , Feminino , Fluorescência , Humanos
16.
Int J Biol Macromol ; 92: 467-475, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27435006

RESUMO

Two new spiro-acridines were synthesized by introducing cyano-N-acylhydrazone between the acridine and phenyl rings followed by spontaneous cyclization. The final compounds (E)-1'-(benzylideneamino)-5'-oxo-1',5'-dihydro-10H-spiro[acridine-9,2'-pyrrole]-4'-carbonitrile (AMTAC-01) and (E)-1'-((4-methoxybenzylidene)amino)-5'-oxo-1',5'-dihydro-10H-spiro[acridine-9,2'-pyrrole]-4'-carbonitrile (AMTAC-02) were evaluated for their interactions with calf thymus DNA, antiproliferative and human topoisomerase I and IIα inhibitory activities. Both compounds presented ability to bind DNA. The binding constant determined by UV-vis spectroscopy was found to be 104M-1. Antiproliferative assay demonstrated that AMTAC-01 and AMTAC-02 were most active against prostate and melanoma tumor cell lines, respectively. The compound did not present Topo I inhibitory activity. However, both derivatives displayed topoisomerase IIα inhibitory activity comparable to amsacrine, and AMTAC-02 was more potent than AMTAC-01 with methoxy substituent group on phenyl ring. This study demonstrates that the new derivatives are promising molecules with topoisomerase IIα inhibitory and antiproliferative activities.


Assuntos
Acridinas/farmacologia , DNA Topoisomerases/metabolismo , DNA/metabolismo , Compostos de Espiro/farmacologia , Inibidores da Topoisomerase/farmacologia , Acridinas/síntese química , Acridinas/química , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Bovinos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Compostos de Espiro/síntese química , Compostos de Espiro/química
17.
Micron ; 90: 114-122, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27668344

RESUMO

The aim of the present study was to investigate ultrastructural changes induced by (Z)-2-(acridin-9-ylmethylene)-N-phenylhydrazinecarbothioamide (APHCA) treatment on human breast adenocarcinoma cancer cells MCF-7, besides the evaluation of phosphatidylserine externalization and DNA fragmentation in treated cells. Cell viability analysis demonstrated concentration and time-manner cytotoxicity. Treated MCF-7 cells did not expose phosphatidylserine residues to the external plasma membrane surface and DNA fragmentation was not visualized by electrophoresis. Light microscopy showed compromised cell density and presence of vacuolization after APHCA treatment with 60µM. Scanning and transmission electron microscopies revealed hallmarks of autophagy, namely the presence of membrane bebbling and autophagosomes, besides shrunken cells and cell debris in treated MCF-7 cells. However, more specific tests such as the quantification of mammalian autophagy proteins are necessary to determine the kind of death that is trigged by APHCA.


Assuntos
Acridinas/farmacologia , Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Neoplasias da Mama/patologia , Sobrevivência Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Microscopia Eletrônica de Varredura , Fosfatidilserinas/análise
18.
Int J Clin Exp Pathol ; 7(5): 2337-49, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24966944

RESUMO

Increased sialylation and ß1,6-branched oligosaccharides has been associated with a variety of structural changes in cell surface carbohydrates, most notably in tumorigenesis. Lectins are defined as proteins that preferentially recognize and bind carbohydrate complexes protruding from glycolipids and glycoproteins. This interaction with carbohydrates can be as specific as the interaction between antigen and antibody. Due to this type of interaction lectins have been used as experimental auxiliary tools in histopathological diagnosis of cancer. This study was designed to evaluate the differential expression of sialic acids and ß1,6-N-acetylglucosaminyltransferase V (MGAT5) in invasive (IDC) and in situ (DCIS) ductal carcinoma of the breast and its possible application as prognostic biomarkers. A possible transition between pre-malign and malign lesions was evaluated using DCIS samples. Biopsies were analyzed regarding the expression of MUC1, p53, Ki-67, estrogen receptor, progesterone receptor, HER-2 and MGAT5. α2,6-linked sialic acids residues recognized by SNA lectin was overexpressed in 33.3% of IDC samples and it was related with Ki-67 (p=0.042), PR (p=0.029), lymphnodes status (p=0.017) and death (p=0.011). Regarding survival analysis SNA was the only lectin able to correlate with specific-disease survival and disease-free survival (p=0.024 and p=0.041, respectively), besides, it presents itself as an independent variable by Cox Regression analysis (p= 0.004). Comparing IDC and DCIS cases, only SNA showed different staining pattern (p=0.034). The presence of sialic acids on tumor cell surface can be an indicative of poor prognosis and our study provides further evidence that SNA lectin can be used as a prognostic probe in IDC and DCIS patients.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/enzimologia , Carcinoma Ductal de Mama/enzimologia , Carcinoma Intraductal não Infiltrante/enzimologia , Imuno-Histoquímica , N-Acetilglucosaminiltransferases/análise , Lectinas de Plantas , Proteínas Inativadoras de Ribossomos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/mortalidade , Carcinoma Intraductal não Infiltrante/patologia , Distribuição de Qui-Quadrado , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Invasividade Neoplásica , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores de Tempo , Análise Serial de Tecidos
19.
Folia Histochem Cytobiol ; 52(2): 96-103, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25007177

RESUMO

Hypoxic areas in solid tumors are often associated with poor prognosis and resistance to chemotherapy. The aim of the study was to analyze the expression of galectin-1 (Gal-1), galectin-3 (Gal-3), sialic acid and b1-6 branched glycan structures in hypoxic environment of invasive ductal carcinoma (IDC) of the breast. We performed lectin histochemistry with phytohemag glutinin-L (L-PHA) and Sambucus nigra lectin (SNA); and immunohistochemistry for Gal-1, Gal-3, carbonic anhydrase IX, hypoxia-inducible factor, estrogen receptor (ER), progesterone receptor and human epidermal growth factor receptor type-2 for 86 IDC samples. Patients with markers positive for hypoxia were mostly ER-negative (p = 0.003) and presented with more nodal invasion than the non-hypoxic group (p = 0.0439). Concerning the glycobiological aspects, the hypoxic group expressed more of Gal-3 (p = 0.0021) and SNA ligands (p = 0.0498), however, there was no association between lectin- and galectin-staining and clinical and histopathological data. Our results suggest a change in the glycomic profile of patients within hypoxic regions of IDC. However, further studies are needed to evaluate the role of lectin- and galectin-ligands in tumor's hypoxic environment, as well as their potential to be used as therapeutic targets.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Galectina 1/genética , Galectina 3/genética , Oxigênio/metabolismo , Adulto , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Anidrases Carbônicas/genética , Anidrases Carbônicas/metabolismo , Carcinoma Ductal de Mama/metabolismo , Estudos de Casos e Controles , Hipóxia Celular , Feminino , Galectina 1/metabolismo , Galectina 3/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo
20.
Int J Clin Exp Pathol ; 7(7): 3800-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25120756

RESUMO

This work aimed to evaluate the glycophenotype in normal prostate, bening prostatic hyperplasia (BPH) and prostatic adenocarcinoma (PCa) tissues by a chemiluminescent method. Concanavalin A (Con A), Ulex europaeus agglutinin (UEA-I) and Peanut agglutinin (PNA) lectins were conjugated to acridinium ester (lectins-AE). These conjugates remained capable to recognize their specific carbohydrates. Tissue samples were incubated with lectins-AE. The chemiluminescence of the tissue-lectin-AE complex was expressed in relative light units (RLU). Transformed tissues (0.25 cm(2) by 8 µm of thickness) showed statistical significant lower α-D-glucose/mannose (BPH: 226,931 ± 17,436; PCa: 239,520 ± 12,398) and Gal-ß(1-3)-GalNAc (BPH: 28,754 ± 2,157; PCa: 16,728 ± 1,204) expression than normal tissues (367,566 ± 48,550 and 409,289 ± 22,336, respectively). However, higher α-L-fucose expression was observed in PCa (251,118 ± 14,193) in relation to normal (200,979 ± 21,318) and BHP (169,758 ± 10,264) tissues. It was observed an expressive decreasing of the values of RLU by inhibition of the interaction between tissues and lectins-AE using their specific carbohydrates. The relationship between RLU and tissue area showed a linear correlation for all lectin-AE in both transformed tissues. These results indicated that the used method is an efficient tool for specific, sensitive and quantitative analyses of prostatic glycophenotype.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/análise , Carboidratos/análise , Neoplasias da Próstata/metabolismo , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Carboidratos/biossíntese , Humanos , Imuno-Histoquímica , Lectinas , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia
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