Browsing by Author "Henrique, Rui"
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- Analysis of volatile human urinary metabolome by solid-phase microextraction in combination with gas chromatography–mass spectrometry for biomarker discovery: application in a pilot study to discriminate patients with renal cell carcinomaPublication . Monteiro, Márcia; Carvalho, Márcia; Henrique, Rui; Jerónimo, Carmen; Moreira, Nathalie; Bastos, Maria de Lourdes; Guedes de Pinho, PaulaA new and simple analytical approach consisting of headspace-solid phase microextraction (HS-SPME) sampling coupled with gas chromatography-ion trap/mass spectrometry (GC-IT/MS) was developed to study the volatile human urinary metabolome. A central composite design (CCD) was used in the optimisation of extraction conditions. Fibre selection and evaluation of pH influence were performed using an univariate mode and the influence of other parameters, such as the time and temperature of extraction, time of incubation and salt addition, that affect the efficiency of the SPME sampling, was carried out using a CCD. With a sample volume of 2 mL, the optimal conditions in terms of total response values and reproducibility were achieved by performing analyses with a divinylbenzene/polydimethylsiloxane (DVB/PDMS) fibre, in an acidic pH (pH 2) with the addition of 0.59 g of NaCl, allowing the sample to equilibrate for 9 min and extracting at 68 °C for 24 min. The applicability of the optimised method was then tested in a pilot non-target analysis of urine samples obtained from patients with renal cell carcinoma (RCC) and healthy individuals. Chemometric unsupervised analyses performed on the volatile pattern acquired for these samples clearly showed the potential of volatile urinary metabolome to discriminate between RCC and control patients.
- Aplicação do volatiloma urinário no diagnóstico não invasivo do carcinoma de células renaisPublication . Pinto, Joana; Amaro, Filipa; Lima, Ana Rita; Carvalho-Maia, Carina; Jerónimo, Carmen; Henrique, Rui; Bastos, Maria de Lourdes; Carvalho, Márcia; Guedes de Pinho, PaulaO carcinoma de células renais do subtipo células claras (ccCCR) representa o tipo mais comum (~70%) de cancro renal. Investigações recentes sugerem que o desenvolvimento deste tipo de cancro está relacionado com alterações metabólicas induzidas por mutações que ocorrem em genes que controlam o metabolismo celular (p.ex., von Hippel–Lindau e fumarato hidratase). Deste modo, o estudo de potenciais biomarcadores de ccCCR, através de uma abordagem metabolómica, torna-se bastante pertinente e atual. Em particular, a fração volátil do metaboloma urinário tem revelado resultados muito promissores na identificação de painéis de biomarcadores com elevada sensibilidade para a deteção de cancros urológicos. Devido aos avanços consideráveis na área dos sensores bioelectrónicos, espera-se que num futuro próximo este tipo de cancro possa ser diagnosticado de uma forma simples, rápida e não invasiva em contexto clínico. Objetivos: Este trabalho teve como objetivo principal a identificação de um painel de biomarcadores para deteção não invasiva de ccCCR através da análise do perfil volátil da urina de doentes com ccCCR (n=75) e de indivíduos controlo (sem cancro, n=75). Material e Métodos: Os compostos orgânicos voláteis (COVs), e mais especificamente os compostos carbonílicos voláteis (CCVs), presentes na urina foram analisados por microextração em fase sólida por headspace e cromatografia gasosa acoplada à espectrometria de massa (HS-SPME-GC-MS). Os dados obtidos foram pré-processados e analisados com recurso a ferramentas bioinformáticas. Resultados: Os modelos de classificação obtidos para as análises de COVs e CCVs mostraram uma boa separação entre as urinas de doentes com ccCCR e controlos, com áreas sob a curva (AUC) de 0,846 e 0,818, respetivamente. No total, 22 compostos revelaram alterações estatisticamente significativas entre os dois grupos, incluindo vários aldeídos, cetonas, hidrocarbonetos aromáticos e terpenos. Foi ainda encontrado um conjunto de seis potenciais biomarcadores de ccCCR que revelou uma AUC de 0.869, sensibilidade de 80%, especificidade de 82% e exatidão de 81%. Deste painel fazem parte o octanal, 3-metilbutanal, benzaldeído, 2-furaldeído, 4-heptanona e p-cresol. As desregulações observadas nos níveis destes compostos sugerem alterações no metabolismo energético e uma maior expressão das enzimas ligadas a processos de carcinogénese. Conclusões: Estes resultados confirmam o potencial da assinatura volátil da urina para a deteção não invasiva de ccCCR e revelam um conjunto de biomarcadores moleculares que podem ser utilizados no desenvolvimento de novos materiais que permitam o seu reconhecimento por sensores bioelectrónicos, comummente chamados de “E-noses”.
- Biological activities of portuguese propolis: protection against free radical-induced erythrocyte damage and inhibition of human renal cancer cell growth in vitroPublication . Valente, Maria J.; Baltazar, Ana F.; Henrique, Rui; Estevinho, Letícia; Carvalho, MárciaThis study reports for the first time the biological properties of Portuguese propolis. The antioxidant potential of propolis samples from Bornes (Northeast) and Fundão (Centre) regions of Portugal was evaluated by their ability to inhibit the 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced oxidative hemolysis and lipid peroxidation in human erythrocytes. Bornes and Fundão propolis strongly protected the erythrocyte membrane from hemolysis (IC(50) of 6.3±0.7 and 10.4±2.7 μg/ml, respectively), in a time- and concentration-dependent manner. This effect was found to be significantly higher than that presented by ascorbic acid (IC(50) of 31.0±5.6 μg/ml). In addition, human erythrocytes treated with propolis extracts showed concentration-dependent decrease in levels of malondialdehyde, a breakdown product of lipid peroxidation. Propolis extracts were also assayed for their anticancer properties on human renal cell carcinoma (RCC). Primary cultures of normal and cancerous renal cells derived from RCC patients, in addition to A-498 cell line, were treated with propolis extracts (0-100 μg/ml). Cytotoxic and antiproliferative effects were determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Propolis extracts exhibited selective toxicity against malignant cells compared to normal cells. In vitro RCC growth was strongly inhibited by Bornes and Fundão propolis in a concentration-dependent manner. Our results indicate that Portuguese propolis constitutes an excellent source of effective natural antioxidant and chemopreventive agents.
- Biomarkers in bladder cancer: a metabolomic approach using in vitro and ex vivo model systemsPublication . Rodrigues, Daniela; Jerónimo, Carmen; Henrique, Rui; Belo, Luís; Bastos, Maria de Lourdes; Guedes de Pinho, Paula; Carvalho, MárciaMetabolomics has recently proved to be useful in the area of biomarker discovery for cancers in which early diagnostic and prognostic biomarkers are urgently needed, as is the case of bladder cancer (BC). This article presents a comprehensive review of the literature on the metabolomic studies on BC, highlighting metabolic pathways perturbed in this disease and the altered metabolites as potential biomarkers for BC detection. Current disease model systems used in the study of BC metabolome include in vitro-cultured cancer cells, ex vivo neoplastic bladder tissues and biological fluids, mainly urine but also blood serum/plasma, from BC patients. The major advantages and drawbacks of each model system are discussed. Based on available data, it seems that BC metabolic signature is mainly characterized by alterations in metabolites related to energy metabolic pathways, particularly glycolysis, amino acid and fatty acid metabolism, known to be crucial for cell proliferation, as well as glutathione metabolism, known to be determinant in maintaining cellular redox balance. In addition, purine and pyrimidine metabolism as well as carnitine species were found to be altered in BC. Finally, it is emphasized that, despite the progress made in respect to novel biomarkers for BC diagnosis, there are still some challenges and limitations that should be addressed in future metabolomic studies to ensure their translatability to clinical practice.
- Caracterização da assinatura metabólica do cancro da próstata em urinaPublication . Lima, Ana Rita; Pinto, Joana; Barros‑Silva, Daniela; Jerónimo, Carmen; Henrique, Rui; Bastos, Maria de Lourdes; Carvalho, Márcia; Guedes de Pinho, Paula
- Caracterização do exometaboloma volátil de linhas celulares de cancro renal com diferentes potenciais metastáticos e subtipos histológicosPublication . Amaro, Filipa; Pinto, Joana; Rocha, Sílvia; Araújo, Ana Margarida; Miranda-Gonçalves, Vera; Jerónimo, Carmen; Henrique, Rui; Bastos, Maria de Lourdes; Carvalho, Márcia; Guedes de Pinho, PaulaO Carcinoma de Células Renais (CCR) representa o terceiro cancro urológico mais frequente e letal em Portugal. Este tipo de cancro inclui vários subtipos histológicos com diferentes potenciais metastáticos, sendo o carcinoma de células claras (ccCCR) e o papilar (pCCR) os mais comuns. É atualmente reconhecida a importância da descoberta de biomarcadores moleculares específicos para o diagnóstico e estadiamento do CCR de forma a superar as limitações dos métodos existentes (ecografia, tomografia computorizada e nefrectomia). O uso da metabolómica constitui uma das abordagens mais promissoras para a identificação de biomarcadores, uma vez que o metabolismo das células tumorais é muito diferente do das células normais. Desta forma, estudos recentes têm mostrado o potencial dos compostos orgânicos voláteis (COVs) e compostos carbonílicos voláteis (CCVs), não só na identificação de novos biomarcadores, mas também na compreensão de vias metabólicas envolvidas na carcinogénese. Objetivos: Este trabalho incluiu o estudo do exometaboloma volátil de linhas celulares dos dois subtipos histológicos mais comuns de CCR (ccCCR e pCCR) com diferentes potenciais metastáticos. Assim, o objetivo principal deste trabalho é identificar os COVs e CCVs, presentes no meio extracelular (exometaboloma), com potencial para serem utilizados como biomarcadores no processo de estadiamento de CCR e consequentemente ajudar na escolha da terapêutica mais dirigida. Material e Métodos: De modo a avaliar as diferenças na composição volátil do exometaboloma de três linhas celulares de ccCCR (não metastáticas: 769-P, 786-O; metastáticas: Caki-1) e duas de pCCR (não metastática: Caki-2; metastática: ACHN), os COVs e CCVs foram extraídos no headspace do meio de cultura por microextração em fase sólida (HS-SPME) e analisados por cromatografia gasosa acoplada à espectrometria de massa (GC-MS). Os dados foram posteriormente tratados através de métodos de análise estatística multivariada e univariada. Resultados: Os resultados obtidos demonstraram que o exometaboloma volátil é mais robusto a discriminar células com diferentes potenciais metastáticos do que a discriminar entre os dois subtipos histológicos. No entanto, foram encontradas diferenças significativas nos níveis de quinze compostos entre ccCCR e pCCR, tais como o 2,4-dimetil-1-hepteno, 3-careno e 4-metilbenzaldeído. Na comparação entre as linhas celulares metastáticas e não metastáticas de ccCCR, foram detetadas alterações nos níveis de diversos alcanos, alcenos e derivados de benzeno, enquanto que nas linhas celulares pCCR, as principais alterações encontradas foram em compostos pertencentes à classe dos aldeídos e cetonas, como o acetaldeído e a 2-pentadecanona. Conclusões: Os resultados obtidos revelaram o potencial do exometaboloma volátil na identificação de biomarcadores promissores para o diagnóstico e estadiamento de CCR.
- Cocaine-induced kidney toxicity: an in vitro study using primary cultured human proximal tubular epithelial cellsPublication . Valente, Maria João; Henrique, Rui; Vilas-Boas, Vânia; Silva, Renata; Bastos, Maria de Lourdes; Carvalho, Félix; Guedes de Pinho, Paula; Carvalho, MárciaRenal failure resulting from cocaine abuse has been well documented, although the underlying mechanisms remain to be investigated. In the present study, primary cultured human proximal tubular epithelial cells (HPTECs) of the kidney were used to investigate its ability to metabolize cocaine, as well as the cytotoxicity induced by cocaine and its metabolites benzoylecgonine (BE), ecgonine methyl ester (EME) and norcocaine (NCOC). Gas chromatography/ion trap-mass spectrometry (GC/IT-MS) analysis of HPTECs exposed to cocaine (1 mM) for 72 h confirmed its metabolism into EME and NCOC, but not BE. EME levels increased along the exposure time to cocaine, while NCOC concentration diminished after reaching a maximum at 6 h, indicating a possible secondary metabolism for this metabolite. Cocaine promoted a concentration-dependent loss of cell viability, whereas BE and EME were found to be non-toxic to HPTECs at the tested conditions. In contrast, NCOC revealed to have higher intrinsic nephrotoxicity than the parent compound. Moreover, cocaine-induced cell death was partially reversed in the presence of ketoconazole (KTZ), a potent CYP3A inhibitor, supporting the hypothesis that NCOC may play a role in cocaine-induced nephrotoxicity. Cocaine-induced cytotoxicity was found to involve intracellular glutathione depletion at low concentrations and to induce mitochondrial damage at higher concentrations. Under the present experimental conditions, HPTECs death pathway followed an apoptotic pattern, which was evident for concentrations as low as 0.1 mM.
- Discrimination between the human prostate normal and cancer cell exometabolome by GC-MSPublication . Lima, Ana Rita; Araújo, Ana Margarida; Pinto, Joana; Jerónimo, Carmen; Henrique, Rui; Bastos, Maria de Lourdes; Carvalho, Márcia; Guedes de Pinho, PaulaSerum prostate-specific antigen (PSA) is currently the most used biomarker in clinical practice for prostate cancer (PCa) detection. However, this biomarker has several drawbacks. In this work, an untargeted gas chromatography-mass spectrometry (GC-MS)-based metabolomic profiling of PCa cells was performed to prove the concept that metabolic alterations might differentiate PCa cell lines from normal prostate cell line. For that, we assessed the differences in volatile organic compounds (VOCs) profile in the extracellular medium (exometabolome) of four PCa cell lines and one normal prostate cell line at two pH values (pH 2 and 7) by GC-MS. Multivariate analysis revealed a panel of volatile metabolites that discriminated cancerous from normal prostate cells. The most altered metabolites included ketones, aldehydes and organic acids. Among these, we highlight pentadecane-2-one and decanoic acid, which were significantly increased in PCa compared to normal cells, and cyclohexanone, 4-methylheptan-2-one, 2-methylpentane-1,3-diol, 4-methylbenzaldehyde, 1-(3,5-dimethylfuran-2-yl)ethanone, methyl benzoate and nonanoic acid, which were significantly decreased in PCa cells. The PCa volatilome was markedly influenced by the VOCs extraction pH, though the discriminant capability was similar. Overall, our data suggest that VOCs monitoring has the potential to be used as a PCa screening methodology.
- Evaluation of immunoexpression and MDR1 promoter methylation levels in prostatic tissue samplesPublication . Moura, Inês; Costa, Vera L.; Pais, Irene; Ribeiro, Franclim R.; Henrique, Rui; Jerónimo, CarmenOs objectivos deste estudo foram: (1) Determinar os níveis de metilação do promotor do MDR1 em tecido prostático com adenocarcinoma (CaP), neoplasia intraepitelial prostática de alto grau (HGPIN), hiperplasia benigna (BPH) e tecido morfologicamente normal (MNP). (2) Correlacionar os níveis de metilação com a imunoexpressão da gp-P. Os nossos resultados demonstram que a hipermetilação do MDR1 constitui um mecanismo eficaz de regulação da sua expressão. Estudos futuros permitirão avaliar o impacto destes resultados na terapêutica do cancro da próstata. Our aims were: (1) To determine the MDR1 methylation levels in tissue of Prostate cancer (PCa), high grade prostatic intraepithelial neoplasia (HGPIN), benign prostatic hyperplasia (BPH) and morphologically normal prostate tissue (MNP); (2) to correlate the methylation levels of the MDR1 promoter with the immunoexpression of P-gp. Our results demonstrate that MDR1 hypermethylation constitutes an effective mechanism of P-gp expression regulation. Future studies will be able to evaluate the impact of these results in the treatment of PCa patients.
- Further insights into chemical characterization through GC–MS and evaluation for anticancer potential of Dracaena draco leaf and fruit extractsPublication . Valente, Maria João; Guedes de Pinho, Paula; Henrique, Rui; Pereira, José A.; Carvalho, MárciaThe present study reports for the first time the amino acid and fatty acid compositions and the antitumoral activity of aqueous extracts obtained from Dracaena draco L. leaf and fruit. Metabolite profiles were determined by gas chromatography-ion trap-mass spectrometry (GC-IT-MS), with several amino acids, palmitic, linolenic and stearic acid being identified in the leaf extract, and only proline, oleic and stearic acid in the fruit extract. The in vitro antiproliferative activities of the extracts were tested against human colon (Caco-2), kidney (A-498), and liver (HepG2) cancer cell lines. In addition, primary cultures of normal and cancerous renal cells derived from kidney cancer patients were treated with D. draco extracts (0-400 μg/mL). Antiproliferative and cytotoxic effects were determined by the MTT assay. D. draco extracts inhibited proliferation of human colon and renal tumor cells in vitro, whereas no or weak effect was observed in HepG2 cells. Compared to the fruit extract, D. draco leaf extract exhibited stronger antiproliferative activity against all cancer cells. Our results indicate that D. draco, particularly the leaf, may be useful as a cancer chemopreventive and/or chemotherapeutic agent for colon and kidney cancers.
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