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1.
Mol Biol Rep ; 46(5): 4827-4841, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31270760

RESUMO

Salvia lachnostachys is an herbaceous plant with anti-inflammatory, analgesic and cytotoxic properties. This study investigated the antitumor effect of an ethanolic extract of Salvia lachnostachys leaves (EES) in a solid Ehrlich carcinoma model. Ehrlich cells were inoculated subcutaneously in the right pelvic member (2 × 106 cells) in female Swiss mice. The animals were treated with vehicle (10 mL kg-1, p.o.), EES (30 and 100 mg kg-1, p.o.), or methotrexate (2.5 mg kg-1, i.p.) for 21 days (early treatment) or 14 days (late treatment) after tumor inoculation, or 10 days before tumor inoculation and continued for 21 days after tumor inoculation (chemopreventive treatment). The acute toxicity test was performed according OECD guidelines Late treatment with EES had no antitumor effect. Early treatment with 100 mg kg-1 EES prevented tumor development, increased tumor necrosis factor-α (TNF-α) levels and decreased tumor superoxide dismutase (SOD) activity, interleukin-10 (IL-10) levels and Cyclin D1 expression, and tumor cell necrosis was observed. Chemopreventive treatment with EES for 10 and 31 days prevented tumor development in the same manner. EES treatment for 31 days decreased hepatic and tumor SOD activity, tumor IL-10 levels and Cyclin D1 expression, and increased tumor reduced glutathione, N-acetylglucosaminidase, reactive oxygen species, lipid peroxidation, TNF-α levels and Nrf2 expression. No toxicity was observed in the acute toxicity assay. In conclusion, EES had an antitumor effect by inhibiting Cyclin D1 expression and increasing inflammation with early and chemopreventive treatment. Modulation of the antioxidant system also contribute for the antitumor effects of EES.


Assuntos
Anticarcinógenos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/farmacologia , Salvia/química , Animais , Anticarcinógenos/química , Antineoplásicos Fitogênicos/química , Carcinoma de Ehrlich/genética , Carcinoma de Ehrlich/metabolismo , Quimioprevenção , Cromatografia Líquida de Alta Pressão , Ciclina D1/genética , Ciclina D1/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Camundongos , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Folhas de Planta/química , Espécies Reativas de Oxigênio/metabolismo
2.
Vet Pathol ; 55(4): 510-516, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29566609

RESUMO

Estrogen receptor α (ERα) has an important role in mammary carcinogenesis, prognosis, and treatment. In human and canine mammary cancer, the most aggressive tumors show loss of ERα expression, which in human breast cancer has been attributed to methylation of the cytosine followed by guanine (CpG) island within the estrogen receptor α gene ( ESR1) promoter. This study aimed to investigate the role of ESR1 CpG island (CGI) methylation in ERα expression in canine mammary tumors. Twenty-one canine mammary samples were sorted into three groups: malignant tumor (n = 9), benign tumor (n = 8), and normal gland (n = 4). Immunohistochemical analysis and reverse-transcription quantitative real-time PCR were performed to assess ERα expression and ESR1 mRNA levels. The methylation status was determined using sodium-bisulfite-treated DNA sequencing. All normal mammary glands and benign tumors showed high ERα expression (score range, 5-8). Six of the nine malignant tumors did not show ERα expression (score 0), two had score 2, and one had score 4. Lower ERα ( P < .005) and ESR1 mRNA levels ( P < .005) were found in malignant mammary tumors than in the other two groups. Canine ESR1 has an intragenic and non-promoter-associated CGI, different from humans. No significant variation in methylation percentage was observed among the groups, suggesting that ESR1 is not regulated by DNA methylation, unlike that in humans. This difference should be considered in further research using ERα as a biomarker for mammary tumors in canine studies on ERα-targeting therapy.


Assuntos
Biomarcadores Tumorais/genética , Receptor alfa de Estrogênio/genética , Neoplasias Mamárias Animais/genética , Animais , Ilhas de CpG/genética , Metilação de DNA , Cães , Feminino , Neoplasias Mamárias Animais/diagnóstico , Neoplasias Mamárias Animais/patologia , Prognóstico , Regiões Promotoras Genéticas/genética
3.
J Clin Lab Anal ; 31(2)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27554451

RESUMO

BACKGROUND: The glucokinase regulatory protein (GCKR) regulates the activity of the glucokinase (GCK), which plays a key role in glucose homeostasis. Genetic variants in GCK have been associated with diabetes and gestational diabetes (GDM). Due to the relationship between GCKRP and GCK, polymorphisms in GCKR are also candidates for genetic association with GDM. The aim of this study was to evaluate the association between the GCKR rs780094 polymorphism and GDM in a Brazilian population. METHODS: 252 unrelated Euro-Brazilian pregnant women were classified as control (healthy pregnant women, n = 125) and GDM (pregnant women with GDM, n = 127) age-matched groups. Clinical and anthropometric data were obtained from all subjects. The GCKR rs780094 polymorphism was genotyped using fluorescent probes (TaqMan® , code C_2862873_10). RESULTS: Both groups were in Hardy-Weinberg equilibrium. The GCKR rs780094 polymorphism was associated with GDM in codominant and dominant models (P = 0.022 and P = 0.010, respectively). The minor allele (T) frequency for the control group in the study was 38.4% (95% CI: 32-44%), similar to frequencies reported for other Caucasian populations. CONCLUSION: Carriers of the C allele of rs780094 were 1.41 (odds ratio, 95% CI, 0.97-2.03) times more likely to develop GDM.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Diabetes Gestacional/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Adulto , Alelos , Brasil , Diabetes Mellitus Tipo 2/genética , Feminino , Frequência do Gene/genética , Genótipo , Humanos , Gravidez , Fatores de Risco
4.
Carbohydr Polym ; 336: 122105, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670749

RESUMO

In situ forming hydrogels are promising for biomedical applications, especially in drug delivery. The precursor solution can be injected at the target site, where it undergoes a sol-gel transition to afford a hydrogel. In this sense, the most significant characteristic of these hydrogels is fast gelation behavior after injection. This study describes an all-polysaccharide, rapidly in situ-forming hydrogel composed of carboxymethyl chitosan (CMCHT) and hydroxyethyl cellulose functionalized with aldehyde groups (HEC-Ald). The HEC-Ald was synthesized through acetal functionalization, followed by acid deprotection. This innovative approach avoids cleavage of pyran rings, as is inherent in the periodate oxidation approach, which is the most common method currently employed for adding aldehyde groups to polysaccharides. The resulting hydrogel exhibited fast stress relaxation, self-healing properties, and pH sensitivity, which allowed it to control the release of an encapsulated model drug in response to the medium pH. Based on the collected data, the HEC-Ald/CMCHT hydrogels show promise as pH-sensitive drug carriers.


Assuntos
Aldeídos , Celulose , Celulose/análogos & derivados , Quitosana , Quitosana/análogos & derivados , Hidrogéis , Quitosana/química , Concentração de Íons de Hidrogênio , Celulose/química , Hidrogéis/química , Aldeídos/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Polissacarídeos/química
5.
Chem Biol Interact ; 387: 110790, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37939893

RESUMO

Breast cancer is a high-magnitude public health problem, continually challenging physicians and scientists worldwide in the field of drug therapy. 4-nitrochalcone (4NC) is a phenolic compound that has promising antitumor activity in vitro, but its application in breast cancer treatment is still poorly explored. This study aimed to evaluate the action of 4NC in vitro and in vivo breast cancer models. The cytotoxic potential of 4NC was tested towards MCF-7 and MDA-MD-231 breast cancer cells, with a lower impact in the non-tumor lineage HB4a. For in vivo studies, solid Ehrlich carcinoma (SEC) was used, a syngeneic mouse model with non-nuclear estrogen and progesterone positivity, characterized by immunohistochemistry. Daily oral administration of 4NC (25 mg kg-1) for 21 days led to a consistent reduction in tumor growth compared to the vehicle group. No signs of toxicity evaluated by hematological, biochemical, histological, and oxidative stress parameters were observed in mice, and the DL50 was >2000 mg kg-1. The effectors Raptor and S6K1 showed decreased activation, with a consequent reduction in protein synthesis; concomitantly, there was an increase in LC3-II levels, but the protective autophagic response was not completed, with the maintenance of p62 levels and cell death. These results open new possibilities for the use of 4NC as a tumor cell metabolism modulating agent.


Assuntos
Antineoplásicos , Chalconas , Neoplasias , Animais , Camundongos , Humanos , Preparações Farmacêuticas , Chalconas/farmacologia , Chalconas/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Morte Celular , Autofagia , Linhagem Celular Tumoral , Células MCF-7 , Apoptose
6.
Exp Parasitol ; 135(1): 9-14, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23748160

RESUMO

Amoebae of the genus Acanthamoeba are free-living protozoa that can cause granulomatous encephalitis and keratitis in humans. In this study, four clinical and three household dust isolates obtained in Vitória, Espírito Santo, Brazil were characterized by their morphological, genotypic, and physiological properties. All isolates belonged to group II according to Pussard and Pons' cyst morphology. Analysis of their 18S rDNA sequence identified one isolate from household dust as genotype T11 and the others six samples as genotype T4. Five T4 isolates presented a highly variable region (DF3) in 18S rDNA identical to those previously described. Physiological assays carried out with trophozoites in co-culture with bacteria or in axenic conditions showed all samples tolerated temperatures up to 37°C, regardless of culture method. One keratitis isolate grew at 42°C in co-culture with bacteria. Most isolates in co-culture survived at 1.0M, except a T11 isolate, which tolerated up to 0.5M. The isolates did not grow at 42°C and did not tolerate 0.5M and 1.0M under axenic condition. This is the first report of 18S rRNA gene genotyping applied to Acanthamoeba isolated from keratitis patients in Brazil. The results also indicated that osmo-tolerance is dependent on the culture system.


Assuntos
Ceratite por Acanthamoeba/parasitologia , Acanthamoeba/classificação , Acanthamoeba/genética , Acanthamoeba/fisiologia , Acanthamoeba/ultraestrutura , Brasil , Clonagem Molecular , Córnea/parasitologia , DNA de Protozoário/química , DNA Ribossômico/química , Poeira , Genótipo , Humanos , Dados de Sequência Molecular , Concentração Osmolar , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Temperatura
7.
J Clin Lab Anal ; 27(2): 155-61, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23424166

RESUMO

BACKGROUND: Diarrheagenic Escherichia coli (DEC) strains are important causes of diarrhea. However, they cannot be distinguished from E. coli of the intestinal microbiota by conventional microbiological tests. METHODS: This work presents a two-system multiplex PCR for detection of DEC. Primers for 16S rRNA gene were added as internal amplification control to validate negative reactions. The multiplex-PCR system 1 contains primers for detection of Shiga toxin producing E. coli (STEC; stx1, stx2), enteropathogenic E. coli (EPEC; eae, bfpA), atypical enteropathogenic E. coli (aEPEc; eae), enteroinvasive E. coli (ETEC; lt, st), enteroinvasive E. coli (EIEC; ial), and the internal amplification control 16S rRNA. The system 2 contains primers for EIEC (ipaH), enteroaggregative E. coli (CVD432), diffusely adherent E. coli (daaE), and 16S rRNA. The protocol was tested with E. coli reference strains, and also with cultures of fecal specimens of people with diarrhea and healthy controls. RESULTS: The protocol correctly identified the DEC reference strains. No DEC marker was amplified for negative controls; these results were validated by the amplification of a fragment of the 16S rRNA gene. The frequency of DEC was 7.6% for both patients and healthy controls; two Shigella sonnei strains were detected in the group with diarrhea. The identity of the amplicons was confirmed by DNA sequencing. CONCLUSION: The protocol is specific for DEC Shigella and is suitable for clinical laboratories.


Assuntos
Escherichia coli Enteropatogênica/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Escherichia coli Enteropatogênica/genética , Infecções por Escherichia coli/diagnóstico , Fezes/microbiologia , Humanos , Sensibilidade e Especificidade
8.
Nanomedicine (Lond) ; 18(6): 541-554, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-37165970

RESUMO

Aims: Develop and analyze triple-negative breast cancer targeted nanoparticles loaded with the demethylating agent decitabine. Materials & methods: The polymers were synthesized by ring-opening polymerization of D,L-lactide and formulated into nanoparticles via emulsion-evaporation method. The nanoparticles were characterized by physicochemical analysis as well as in vitro using breast cancer cell lineages. Results & conclusion: The targeted nanoparticles exhibited a hydrodynamic diameter of 75 ± 12 nm, zeta potential -6.3 ± 0.2 mV and spherical morphology, and displayed greater in vitro accumulation into MDA-MB-231 (triple-negative breast cancer cell-line) compared with MCF7 and HB4A cell lineages as verified by fluorescence confocal microscopy and significant demethylating effects via ADAM33 screening by PCR.


Assuntos
Neoplasias da Mama , Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Epigênese Genética , Ligantes , Linhagem Celular Tumoral , Nanopartículas/química , Proteínas ADAM
9.
Epigenomics ; 15(24): 1309-1322, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38174426

RESUMO

Background: Dulaglutide emerged as a promising therapeutic option for diabetes mellitus Type 2 (DM2). Aims: Owing to epigenetic similarities between the pathophysiology of DM2 and breast cancer (BC), we investigated the antitumor effect of dulaglutide. Materials & methods: To investigate the effect of dulaglutide, we analyzed the expression of methylated gene promoter regions in BC (ESR1, CDH1 and ADAM33). Results: Dulaglutide increased the expression of ESR1, CDH1 and ADAM33 up to fourfold in the MDA-MB-231 lineage by demethylating the gene promoter regions. This effect was translated to in vivo antitumoral activity and revealed significant tumor inhibition by combining the half-dose of methotrexate with dulaglutide. Conclusion: This therapy may mitigate the severe side effects commonly associated with chemotherapy.


Assuntos
Neoplasias da Mama , Diabetes Mellitus Tipo 2 , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/farmacologia , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/uso terapêutico , Hipoglicemiantes/uso terapêutico , Proteínas ADAM/uso terapêutico
10.
J Nutr Biochem ; 113: 109253, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36565967

RESUMO

The present study characterized oligosaccharide compounds (Oligo) in Cabernet Franc red wine and investigated its antineoplastic effects against mammary tumor cells in vivo and in vitro, isolated or in combination with chemotherapy. The Oligo fraction was characterized by nuclear magnetic resonance spectroscopy and mass spectrometry. The complex mixture of Oligo showed high amounts of oligoxyloglucuronans, oligorhamnogalacturonans, oligoarabinogalactans, and oligoglucans, such as trehalose and isomaltotriose. To investigate the antineoplastic effects of Oligo, Female Swiss mice were subcutaneously inoculated with Ehrlich tumor cells and then received vehicle (distilled water, p.o.), Oligo solution (9, 35, or 70 mg/kg, p.o.), or methotrexate (1.5 mg/kg, i.p.). The treatments were administered in a conventional (21-d) or chemopreventive (42-d) protocol. Oligo reduced the growth of Ehrlich tumors in both protocols and increased the effectiveness of methotrexate in controlling tumor growth. Oligo did not reduce the viability of MCF-7, MDA-MB-231, MDA-MB-436, and HB4a human breast cells that were cultured for 48 h, showing no cytotoxicity. Overall, Oligo exerted an in vivo antineoplastic effect and modulated immune blood cells, dependent on treatment time, and was not directly cytotoxic to tumor cells. Thus, Oligo may indirectly regulate tumor cell development and may be a promising drug for cancer therapy in combination with methotrexate.


Assuntos
Antineoplásicos , Neoplasias da Mama , Neoplasias Mamárias Animais , Vinho , Camundongos , Feminino , Humanos , Animais , Metotrexato/farmacologia , Metotrexato/uso terapêutico , Metotrexato/análise , Vinho/análise , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Oligossacarídeos/farmacologia , Oligossacarídeos/uso terapêutico , Oligossacarídeos/análise , Neoplasias da Mama/tratamento farmacológico
11.
Chem Biol Interact ; 378: 110480, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37059214

RESUMO

Breast cancer is one of the most common types of cancer in the world and current therapeutic strategies present severe drawbacks. l-carvone (CRV), a monoterpene found in Mentha spicata (spearmint), has been reported to have potent anti-inflammatory activity. Here, we examined the role of CRV in breast cancer cell adhesion, migration and invasion in vitro and how this component could suppress the growth of Ehrlich carcinoma-bearing mice. In vivo, treatment with CRV significantly decreased tumor growth, increased tumor necrosis area, and reduced the expression of VEGF and HIF-1α in Ehrlich carcinoma-bearing mice. Furthermore, the anticancer efficacy of CRV was similar to currently used chemotherapy (Methotrexate), and the combination of CRV with MTX potentiated the chemotherapy effects. Further mechanistic investigation in vitro revealed that CRV modulates the interaction of breast cancer cells with the extracellular matrix (ECM) by disrupting focal adhesion, which was shown by scanning electron microscopy (SEM) and immunofluorescence. Moreover, CRV caused a decrease in ß1-integrin expression and inhibited focal adhesion kinase (FAK) activation. FAK is one of the most important downstream activators of several metastatic processes, including MMP-2 mediated invasion and HIF-1α/VEGF angiogenesis stimulus, both of which were found to be reduced in MDA-MB-231 cells exposed to CRV. Our results provide new insight about targeting ß1-integrin/FAK signaling pathway with CRV, which could be a new potential agent in the treatment of breast cancer.


Assuntos
Carcinoma , Fator A de Crescimento do Endotélio Vascular , Animais , Camundongos , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Quinase 1 de Adesão Focal/metabolismo , Integrina beta1/metabolismo , Invasividade Neoplásica , Adesão Celular
12.
Clin Breast Cancer ; 22(4): e604-e614, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35135735

RESUMO

The enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) is a critical engine that supports glucose catabolism. PFKFB3 produces the signaling molecule fructose-2,6-biphosphate (F2,6BP), which activates the second gatekeeper in glycolysis, 6-phosphofructo-1-kinase (PFK-1), and favors the Warburg phenotype. Transcriptional and post-transcriptional processes regulate the abundance and phosphorylation of PFKFB3 in cells, and its activation has been implicated in the progression of several types of cancer. PFKFB3 is important for sustaining glycolysis in the tumorigenesis environment even under unfavorable conditions, thereby promoting metabolic reprogramming, cell proliferation, DNA repair, and drug resistance. Despite its heterogeneous phenotype, breast cancer has unique characteristics that drive the constitutive and inducible expression of PFKFB3 in this opportunistic glycolytic shift. This enzyme is a point of convergence of multiple exogenous and endogenous growth-promoting and oncogenic signaling pathways, especially kinase cascades. The present review summarizes advances in in vitro and in vivo therapy studies that focus on PFKFB3 and the interplay between hormone receptor status and the underlying essential signal transduction system in breast cancer metabolic remodeling.


Assuntos
Neoplasias da Mama , Fosfofrutoquinase-2 , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Glicólise , Humanos , Fosfofrutoquinase-2/genética , Fosfofrutoquinase-2/metabolismo , Fosforilação , Transdução de Sinais
13.
Nanomedicine (Lond) ; 17(9): 645-664, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35438008

RESUMO

Ligand-mediated targeting represents the cutting edge in precision-guided therapy for several diseases. Surface engineering of nanomedicines with ligands exhibiting selective or tailored affinity for overexpressed biomolecules of a specific disease may increase therapeutic efficiency and reduce side effects and recurrence. This review focuses on newly developed approaches and strategies to improve treatment and overcome the mechanisms associated with breast cancer resistance.


Assuntos
Neoplasias da Mama , Nanomedicina , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Ligantes
14.
Chem Biol Interact ; 349: 109641, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34534549

RESUMO

Breast cancer (BC) is the most frequently diagnosed female cancer and second leading cause of death. Despite the discovery of many antineoplastic drugs for BC, the current therapy is not totally efficient. In this study, we investigated the potential of repurposing the well-known diabetes type II drug liraglutide to modulate epigenetic modifications in BC cells lines in vitro and in vivo via Ehrlich mice tumors models. The in vitro results revealed a significant reduction on cell viability, migration, DNMT activity and displayed lower levels of global DNA methylation in BC cell lines after liraglutide treatment. The interaction between liraglutide and the DNMT enzymes resulted in a decrease profile of DNA methylation for the CDH1, ESR1 and ADAM33 gene promoter regions and, consequently, increased their gene and protein expression levels. To elucidate the possible interaction between liraglutide and the DNMT1 protein, we performed an in silico study that indicates liraglutide binding in the catalytic cleft via hydrogen bonds and salt bridges with the interdomain contacts and disturbs the overall enzyme conformation. The in vivo study was also able to reveal that liraglutide and the combined treatment of liraglutide and paclitaxel or methotrexate were effective in reducing tumor growth. Moreover, the modulation of CDH1 and ADAM33 mouse gene expression by DNA demethylation suggests a role for liraglutide in DNMT activity in vivo. Altogether, these results indicate that liraglutide may be further analysed as a new adjuvant treatment for BC.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , DNA (Citosina-5-)-Metiltransferase 1/antagonistas & inibidores , Inibidores Enzimáticos/uso terapêutico , Liraglutida/uso terapêutico , Proteínas ADAM/genética , Animais , Antígenos CD/genética , Neoplasias da Mama/patologia , Caderinas/genética , Linhagem Celular Tumoral , Metilação de DNA/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Feminino , Humanos , Camundongos , Regiões Promotoras Genéticas
15.
BMC Cancer ; 10: 23, 2010 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-20109227

RESUMO

BACKGROUND: CXCL12 is a chemokine that is constitutively expressed in many organs and tissues. CXCL12 promoter hypermethylation has been detected in primary breast tumours and contributes to their metastatic potential. It has been shown that the oestrogen receptor alpha (ESR1) gene can also be silenced by DNA methylation. In this study, we used methylation-specific PCR (MSP) to analyse the methylation status in two regions of the CXCL12 promoter and ESR1 in tumour cell lines and in primary breast tumour samples, and correlated our results with clinicopathological data. METHODS: First, we analysed CXCL12 expression in breast tumour cell lines by RT-PCR. We also used 5-aza-2'-deoxycytidine (5-aza-CdR) treatment and DNA bisulphite sequencing to study the promoter methylation for a specific region of CXCL12 in breast tumour cell lines. We evaluated CXCL12 and ESR1 methylation in primary tumour samples by methylation-specific PCR (MSP). Finally, promoter hypermethylation of these genes was analysed using Fisher's exact test and correlated with clinicopathological data using the Chi square test, Kaplan-Meier survival analysis and Cox regression analysis. RESULTS: CXCL12 promoter hypermethylation in the first region (island 2) and second region (island 4) was correlated with lack of expression of the gene in tumour cell lines. In the primary tumours, island 2 was hypermethylated in 14.5% of the samples and island 4 was hypermethylated in 54% of the samples. The ESR1 promoter was hypermethylated in 41% of breast tumour samples. In addition, the levels of ER alpha protein expression diminished with increased frequency of ESR1 methylation (p < 0.0001). This study also demonstrated that CXCL12 island 4 and ESR1 methylation occur simultaneously at a high frequency (p = 0.0220). CONCLUSIONS: This is the first study showing a simultaneous involvement of epigenetic regulation for both CXCL12 and ESR1 genes in Brazilian women. The methylation status of both genes was significantly correlated with histologically advanced disease, the presence of metastases and death. Therefore, the methylation pattern of these genes could be used as a molecular marker for the prediction of breast cancer outcome.


Assuntos
Neoplasias da Mama/genética , Quimiocina CXCL12/genética , Metilação de DNA , Receptor alfa de Estrogênio/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Quimiocina CXCL12/biossíntese , Ilhas de CpG , Análise Mutacional de DNA , Receptor alfa de Estrogênio/biossíntese , Feminino , Inativação Gênica , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Prognóstico , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Mem Inst Oswaldo Cruz ; 105(3): 318-21, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20512247

RESUMO

Thirty-eight strains of Shiga toxin-producing Escherichia coli (STEC) were characterised in terms of biochemical properties, enterohaemolysin production and plasmid carriage. A wide variation in the biochemical properties was observed among the STEC, with 14 distinct biotypes identified. Biotype 1 was the most common, found in 29% of the strains. Enterohaemolysin production was detected in 29% of the strains. Most of the bacterial strains (95%) carried one or more plasmids and considerable heterogeneity in size and combinations was observed. Seven distinct plasmid profiles were identified. The most common profile, characterised by the presence of a single plasmid of ~90 kb, was found in 50% of these strains. These data indicate extensive diversity among STEC strains. No correlation was found among biotype, serotype, enterohaemolysin production and plasmid profile.


Assuntos
DNA Bacteriano/genética , Proteínas de Escherichia coli/biossíntese , Proteínas Hemolisinas/biossíntese , Plasmídeos/genética , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/metabolismo , Animais , Bovinos , Criança , Eletroforese em Gel de Campo Pulsado , Humanos
17.
Sci Rep ; 10(1): 16477, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020521

RESUMO

Natural products have been recognized as important bioactive compounds on the basis of their wide biological properties. Here we investigated the antitumor effect and molecular mechanisms of the diterpene Fruticuline A (fruti) from Salvia lachnostachys, in human cancer cell lineages and Solid Ehrlich Carcinoma in mice. Fruti reduced MCF-7 and HepG2 proliferation by the reduction of Cyclin D1 levels and decreased NF-κB gene levels in both cell types. Furthermore, fruti also induced apoptosis in HepG2 cells, reduced Bcl-2 gene expression and induced necroptosis by increasing Ripk in MCF-7 cells. In mice, fruti prevented tumor development and reduced Cyclin D1, Bcl-2 and Rela gene levels, and reduced the p-NF-κB/NF-κB ratio in tumor tissue. Furthermore, fruti induced necrosis and apoptosis, increased N-acetyl-ß-D-glucosaminidase and TNF-α levels and reduced IL-10 and Vegf levels in tumor tissue. Collectively, fruti exerts antitumor effects through the inhibition of the NF-κB pathway, reducing Cyclin D1 and Bcl-2 levels. In vitro the apoptosis and necroptosis pathways are involved in the cellular death, whereas in vivo, cells undergo necrosis by increased tumor inflammation and reduction of angiogenesis. Thus, fruticuline A acts in tumor cells by multiple mechanisms and represents a promising molecule for drug development in cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Diterpenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Ciclina D1/metabolismo , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Células Hep G2 , Humanos , Células MCF-7 , Camundongos , NF-kappa B/metabolismo , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
18.
Int J Biol Macromol ; 158: 1071-1081, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32387356

RESUMO

This study investigated the antineoplastic effects and toxicity of long-term treatment with polysaccharides from sweet green pepper (Capsicum annuum [CAP]), and concomitant treatment with CAP + methotrexate (MTX) on mammary tumor cells in vivo and in vitro. Ehrlich tumor cells were subcutaneously inoculated in female Swiss mice. The long-term treatment (31 days) with CAP (100 mg kg-1, p.o.) reduced the tumor growth and did not induce toxicity. The combined treatment protocol of 100 mg kg-1 CAP (p.o.) + 1 mg kg-1 MTX (i.p.) for 21 days inhibited the tumor growth in 95%, higher than the inhibition induced by MTX alone (1.0 or 2.5 mg kg-1, i.p.). In tumors, both CAP and CAP + MTX decreased the gene expression of Vegf, vessel area, and IL-4 and IL-10 levels, and increased IL-6 levels and the degree of necrosis. Treatment with CAP + MTX also increased TNF-α levels in tumors. Additionally, CAP + MTX treatment reduced the viability of human MDA-MB-231 and MDA-MB-436 mammary tumor cells in culture. In fact, CAP exerted antineoplastic effects in vivo and in vitro against mammary tumor cells, possibly by modulating inflammation and angiogenesis. CAP may be a promising adjunct chemotherapy with lower toxicity.

19.
BMC Cancer ; 9: 80, 2009 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-19267929

RESUMO

BACKGROUND: ADAM33 protein is a member of the family of transmembrane glycoproteins composed of multidomains. ADAM family members have different activities, such as proteolysis and adhesion, making them good candidates to mediate the extracellular matrix remodelling and changes in cellular adhesion that characterise certain pathologies and cancer development. It was reported that one family member, ADAM23, is down-regulated by promoter hypermethylation. This seems to correlate with tumour progression and metastasis in breast cancer. In this study, we explored the involvement of ADAM33, another ADAM family member, in breast cancer. METHODS: First, we analysed ADAM33 expression in breast tumour cell lines by RT-PCR and western blotting. We also used 5-aza-2'-deoxycytidine (5azadCR) treatment and DNA bisulphite sequencing to study the promoter methylation of ADAM33 in breast tumour cell lines. We evaluated ADAM33 methylation in primary tumour samples by methylation specific PCR (MSP). Finally, ADAM33 promoter hypermethylation was correlated with clinicopathological data using the chi-square test and Fisher's exact test. RESULTS: The expression analysis of ADAM33 in breast tumour cell lines by RT-PCR revealed gene silencing in 65% of tumour cell lines. The corresponding lack of ADAM33 protein was confirmed by western blotting. We also used 5-aza-2'-deoxycytidine (5-aza-dCR) demethylation and bisulphite sequencing methodologies to confirm that gene silencing is due to ADAM33 promoter hypermethylation. Using MSP, we detected ADAM33 promoter hypermethylation in 40% of primary breast tumour samples. The correlation between methylation pattern and patient's clinicopathological data was not significantly associated with histological grade; tumour stage (TNM); tumour size; ER, PR or ERBB2 status; lymph node status; metastasis or recurrence. Methylation frequency in invasive lobular carcinoma (ILC) was 76.2% compared with 25.5% in invasive ductal carcinoma (IDC), and this difference was statistically significant (p = 0.0002). CONCLUSION: ADAM33 gene silencing may be related to the discohesive histological appearance of ILCs. We suggest that ADAM33 promoter methylation may be a useful molecular marker for differentiating ILC and IDC.


Assuntos
Proteínas ADAM/genética , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Carcinoma Lobular/genética , Inativação Gênica , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/patologia , Linhagem Celular Tumoral , Metilação de DNA , Feminino , Expressão Gênica/genética , Humanos , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética
20.
J Mol Histol ; 39(2): 217-25, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18034316

RESUMO

Quiescin Q6/sulfhydryl oxidases (QSOX) are revisited thiol oxidases considered to be involved in the oxidative protein folding, cell cycle control and extracellular matrix remodeling. They contain thioredoxin domains and introduce disulfide bonds into proteins and peptides, with the concomitant hydrogen peroxide formation, likely altering the redox environment. Since it is known that several developmental processes are regulated by the redox state, here we assessed if QSOX could have a role during mouse fetal development. For this purpose, an anti-recombinant mouse QSOX antibody was produced and characterized. In E(13.5), E(16.5) fetal tissues, QSOX immunostaining was confined to mesoderm- and ectoderm-derived tissues, while in P1 neonatal tissues it was slightly extended to some endoderm-derived tissues. QSOX expression, particularly by epithelial tissues, seemed to be developmentally-regulated, increasing with tissue maturation. QSOX was observed in loose connective tissues in all stages analyzed, intra and possibly extracellularly, in agreement with its putative role in oxidative folding and extracellular matrix remodeling. In conclusion, QSOX is expressed in several tissues during mouse development, but preferentially in those derived from mesoderm and ectoderm, suggesting it could be of relevance during developmental processes.


Assuntos
Feto/enzimologia , Oxirredutases/metabolismo , Animais , Animais Recém-Nascidos , Especificidade de Anticorpos , Imuno-Histoquímica , Masculino , Camundongos , Oxirredutases/análise , Oxirredutases/imunologia , Coelhos , Ratos , Ratos Wistar , Distribuição Tecidual
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