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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.

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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.

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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.

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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.

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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.

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Immobilized lectins are a powerful biotechnological tool for separation and isolation of glycoconjugates. In the present study, polyvinyl alcohol (PVA) and glutaraldehyde (GA) were used as a support for Concanavalin A (Con A) covalent immobilization and for entrapment of Parkia pendula seed gum (PpeG). Con A immobilization yielded approximately 30% and 0.6 M glucose solution was the minimum concentration able to elute fetuin from column. PVA-GA-PpeG column was efficiently recognized by pure P. pendula lectin (PpeL) . These findings indicate that PVA-GA interpenetrated network showed to be an efficient support for lectin covalent immobilization and as affinity chromatography matrix after trapping of PpeG.

Lectinas imobilizadas são uma poderosa ferramenta biotecnológica para a separação e isolamento de glicoconjugados. No presente trabalho álcool polivinílico (PVA) e glutaraldeído (GA) foram utilizados como um suporte para a imobilização covalente da Concanavalina A (Con A) e para aprisionamento da goma de semente de Parkia pendula (PpeG). A eficiência da imobilização da Con A foi aproximadamente 30 % e a concentração mínima de glucose capaz de eluir a fetuína da coluna foi 0,6 M. Coluna de PVA - GA - PpeG foi eficientemente reconhecida pela lectina de P. pendula (PpeL) pura. Estes resultados indicam que a rede interpenetrada de PVA-GA mostrou-se um suporte eficiente para a imobilização covalente de lectina e como matriz de cromatografia de afinidade após aprisionamento de PpeG.

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Immobilized lectins are a powerful biotechnological tool for separation and isolation of glycoconjugates. In the present study, polyvinyl alcohol (PVA) and glutaraldehyde (GA) were used as a support for Concanavalin A (Con A) covalent immobilization and for entrapment of Parkia pendula seed gum (PpeG). Con A immobilization yielded approximately 30% and 0.6 M glucose solution was the minimum concentration able to elute fetuin from column. PVA-GA-PpeG column was efficiently recognized by pure P. pendula lectin (PpeL). These findings indicate that PVA-GA interpenetrated network showed to be an efficient support for lectin covalent immobilization and as affinity chromatography matrix after trapping of PpeG.(AU)

Lectinas imobilizadas são uma poderosa ferramenta biotecnológica para a separação e isolamento de glicoconjugados. No presente trabalho álcool polivinílico (PVA) e glutaraldeído (GA) foram utilizados como um suporte para a imobilização covalente da Concanavalina A (Con A) e para aprisionamento da goma de semente de Parkia pendula (PpeG). A eficiência da imobilização da Con A foi aproximadamente 30 % e a concentração mínima de glucose capaz de eluir a fetuína da coluna foi 0,6 M. Coluna de PVA - GA - PpeG foi eficientemente reconhecida pela lectina de P. pendula (PpeL) pura. Estes resultados indicam que a rede interpenetrada de PVA-GA mostrou-se um suporte eficiente para a imobilização covalente de lectina e como matriz de cromatografia de afinidade após aprisionamento de PpeG.(AU)

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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.

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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.

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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.

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