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1.
Oncogene ; 36(43): 6030-6040, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-28671672

RESUMO

Cancer cells reprogram their metabolism to maintain both viability and uncontrolled proliferation. Although an interplay between the genetic, epigenetic and metabolic rewiring in cancer is beginning to emerge, it remains unclear how this metabolic plasticity occurs. Here, we report that in prostate cancer cells (PCCs) microRNAs (miRNAs) greatly contribute to deregulation of mitochondrial fatty acid (FA) oxidation via carnitine system modulation. We provide evidence that the downregulation of hsa-miR-124-3p, hsa-miR-129-5p and hsa-miR-378 induced an increase in both expression and activity of CPT1A, CACT and CrAT in malignant prostate cells. Moreover, the analysis of human prostate cancer and prostate control specimens confirmed the aberrant expression of miR-124-3p, miR-129-5p and miR-378 in primary tumors. Forced expression of the miRNAs mentioned above affected tumorigenic properties, such as proliferation, migration and invasion, in PC3 and LNCaP cells regardless of their hormone sensitivity. CPT1A, CACT and CrAT overexpression allow PCCs to be more prone on FA utilization than normal prostate cells, also in the presence of high pyruvate concentration. Finally, the simultaneous increase of CPT1A, CACT and CrAT is fundamental for PCCs to sustain FA oxidation in the presence of heavy lipid load on prostate cancer mitochondria. Indeed, the downregulation of only one of these proteins reduces PCCs metabolic flexibility with the accumulation of FA-intermediate metabolites in the mitochondria. Together, our data implicate carnitine cycle as a primary regulator of adaptive metabolic reprogramming in PCCs and suggest new potential druggable pathways for prevention and treatment of prostate cancer.


Assuntos
Carnitina O-Palmitoiltransferase/genética , Proteínas de Membrana Transportadoras/genética , MicroRNAs/genética , Neoplasias da Próstata/genética , Carcinogênese/genética , Carnitina/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Oxirredução , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 173: 476-488, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27718451

RESUMO

Hyperspectral Raman images of human prostatic cells have been collected and analysed with several approaches to reveal differences among normal and tumor cell lines. The objective of the study was to test the potential of different chemometric methods in providing diagnostic responses. We focused our analysis on the ν(CH) region (2800-3100cm-1) owing to its optimal Signal-to-Noise ratio and because the main differences between the spectra of the two cell lines were observed in this frequency range. Multivariate analysis identified two principal components, which were positively recognized as due to the protein and the lipid fractions, respectively. The tumor cells exhibited a modified distribution of the cytoplasmatic lipid fraction (mainly localized alongside the cell boundary) which may result very useful for a preliminary screening. Principal Component analysis was found to provide high contrast and to be well suited for image-processing purposes. Self-Modelling Curve Resolution made available meaningful spectra and relative-concentration values; it revealed a 97% increase of the lipid fraction in the tumor cell with respect to the control. Finally, a univariate approach confirmed significant and reproducible differences between normal and tumor cells.


Assuntos
Próstata/citologia , Neoplasias da Próstata/patologia , Análise de Célula Única/métodos , Análise Espectral Raman/métodos , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Processamento de Imagem Assistida por Computador/métodos , Análise dos Mínimos Quadrados , Masculino , Análise Multivariada , Análise de Componente Principal , Próstata/química , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído
3.
Dig Liver Dis ; 39(10): 922-8, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17693145

RESUMO

BACKGROUND: Fatigue is common in celiac disease. L-Carnitine blood levels are low in untreated celiac disease. L-Carnitine therapy was shown to improve muscular fatigue in several diseases. AIM: To evaluate the effect of L-carnitine treatment in fatigue in adult celiac patients. METHODS: Randomised double-blind versus placebo parallel study. Thirty celiac disease patients received 2 g daily, 180 days (L-carnitine group) and 30 were assigned to the placebo group (P group). The patients underwent clinical investigation and questionnaires (Scott-Huskisson Visual Analogue Scale for Asthenia, Verbal Scale for Asthenia, Zung Depression Scale, SF-36 Health Status Survey, EuroQoL). OCTN2 levels, the specific carnitine transporter, were detected in intestinal tissue. RESULTS: Fatigue measured by Scott-Huskisson Visual Analogue Scale for Asthenia was significantly reduced in the L-carnitine group compared with the placebo group (p=0.0021). OCTN2 was decreased in celiac patients when compared to normal subjects (-134.67% in jejunum), and increased after diet in both celiac disease treatments. The other scales used did not show any significant difference between the two celiac disease treatment groups. CONCLUSION: L-Carnitine therapy is safe and effective in ameliorating fatigue in celiac disease. Since L-carnitine is involved in muscle energy production its decreased absorption due to OCTN2 reduction might explain muscular symptoms in celiac disease patients. The diet-induced OCTN2 increase, improving carnitine absorption, might explain the L-carnitine treatment efficacy.


Assuntos
Carnitina/uso terapêutico , Doença Celíaca/complicações , Fadiga/tratamento farmacológico , Complexo Vitamínico B/uso terapêutico , Administração Oral , Adulto , Biomarcadores/metabolismo , Biópsia , Carnitina/administração & dosagem , Carnitina/farmacocinética , Doença Celíaca/diagnóstico , Doença Celíaca/tratamento farmacológico , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Método Duplo-Cego , Eletroforese em Gel de Poliacrilamida , Fadiga/sangue , Fadiga/etiologia , Feminino , Seguimentos , Humanos , Jejuno/metabolismo , Jejuno/patologia , Masculino , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Projetos Piloto , Qualidade de Vida , Membro 5 da Família 22 de Carreadores de Soluto , Inquéritos e Questionários , Resultado do Tratamento , Complexo Vitamínico B/administração & dosagem , Complexo Vitamínico B/farmacocinética
4.
Gut ; 54(4): 496-502, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15753534

RESUMO

BACKGROUND AND AIMS: Ulcerative colitis (UC) is characterised by refractory inflammatory ulceration and damage to the colon. The mechanisms underlying impaired healing have yet to be defined. As transglutaminase expression resulting in matrix protein cross linking is associated with increased wound healing in a rat model of colitis, we hypothesised that different types of transglutaminase might also play a role in UC. PATIENTS AND METHODS: Endoscopic and histological indices were studied in 26 patients with UC (10 active and 16 inactive) and in 20 normal controls undergoing colonoscopy. Transglutaminase activity was evaluated in plasma (factor XIIIa) by a radioenzymatic method. Factor XIIIa, tissue and keratinocyte transglutaminase protein content, and mRNA expression in the colon were evaluated by western blot analysis and semiquantitative reverse transcription-polymerase chain reaction (RT-PCR), respectively. Colonic location of transglutaminases and their reaction products, the epsilon-(gamma-glutamyl)lysine bonds, was evaluated by immunohistochemistry using specific monoclonal antibodies. RESULTS: Transglutaminase activity was significantly lower in the plasma of patients with active UC (4.2 (2.4) mU/ml; p<0.05 v controls) than in those with inactive UC and controls (10.6 (2.2) and 12.1 (1.7) mU/ml). As shown by western blot, protein levels of tissue transglutaminase and factor XIIIa were unchanged in active UC compared with inactive disease and controls, while the keratinocyte form was reduced in active UC. Tissue transglutaminase and factor XIIIa immunostaining was strongly present in damaged areas colocalising with isopeptide bonds. In contrast, the keratinocyte form was almost absent in active UC and localised in the upper part of the crypts in normal subjects. RT-PCR showed upregulation of tissue transglutaminase mRNA in active UC (320% compared with controls) while keratinocyte transglutaminase gene expression was downregulated in active UC. CONCLUSIONS: The results of the present study support the concept that, in the damaged colon, transglutaminases are needed in response to chronic injury and underline the key role of these enzymes in mucosal healing.


Assuntos
Colite Ulcerativa/enzimologia , Transglutaminases/metabolismo , Adulto , Idoso , Western Blotting , Colite Ulcerativa/sangue , Fator XIIIa/metabolismo , Feminino , Humanos , Mucosa Intestinal/enzimologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Índice de Gravidade de Doença , Transglutaminases/genética , Regulação para Cima , Cicatrização
5.
J Cell Physiol ; 186(3): 414-24, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11169981

RESUMO

The mechanism by which estradiol (E2) acts on cell proliferation is still unclear. In this paper, we report the results of a series of experiments in an attempt to elucidate the effector pathway(s) involved in coupling the E2 receptors binding to cellular growth response in leiomyoma cells (LSMC). Under conditions of E2-dependent growth, E2 treatment of LSMC triggers rapid and transient activation of the MAP-kinase pathway. Interestingly, we demonstrate that the early downstream signal transduction events determined by E2-stimulation in quiescent LSMC, including the rapid protein tyrosine phosphorylation of a subset of intracellular proteins, such GAP, PI-3-K, and PLCgamma, and the concomitant activation of ancillary protein kinases, are related to E2-induced PDGF secretion. Moreover, we identify the PDGF, alone or in association with other growth factors, as the main growth factor involved in the proliferation response of LSMC to E2 stimulation. The addition of neutralizing antibodies anti-PDGF was able to inhibit the mitogenic activity present in LSMC conditioned media samples. On the other hand, E2 did not affect the constitutive expression as well as the ligand affinity of PDGF receptors on LSMC plasmamembrane. Cell treatment with the antiestrogen ICI 182780 correlate both with a perturbation of E2-induced transductional circuit and with the disappearance of the mitogenic factor, PDGF, in LSMC conditioned media; the latter therefore, represents the main autocrine mediator of cell growth modulation, upregulated by E2 and down-regulated by antiestrogenic compound. Our experiments suggest that growth factor secretion is an initial and integral part of the signaling events mediated by the estradiol receptors, not related, at least in part, to E2 transcriptional modulation.


Assuntos
Estradiol/análogos & derivados , Estradiol/farmacologia , Leiomioma/patologia , Sistema de Sinalização das MAP Quinases/fisiologia , Neoplasias Uterinas/patologia , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular , Meios de Cultivo Condicionados , Moduladores de Receptor Estrogênico/farmacologia , Feminino , Fator 2 de Crescimento de Fibroblastos/farmacologia , Fulvestranto , Humanos , Cinética , Leiomioma/fisiopatologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfotirosina/análise , Fator de Crescimento Derivado de Plaquetas/farmacologia , Fator de Crescimento Derivado de Plaquetas/fisiologia , Proteínas Proto-Oncogênicas c-raf/metabolismo , Receptores de Estradiol/fisiologia , Receptores do Fator de Crescimento Derivado de Plaquetas/fisiologia , Células Tumorais Cultivadas , Neoplasias Uterinas/fisiopatologia
6.
J Mater Sci Mater Med ; 10(10/11): 595-600, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-15347972

RESUMO

The understanding of substrate dependence of cellular differentiation is important in the surface design of biocompatible artificial devices as well as cell-incorporated tissue engineered devices. In an attempt to understand some of the genetic and epigenetic aspects of the control of cell differentiation in the presence of two different materials, Chronoflex (CH) and plasma treated Chronoflex coated with Hyaluronan (CH-HA), we used primary cultures of human myogenic cells, a model that encompasses cell proliferation, migration, fusion, and differentiation dependent gene activation. By testing both the material samples on the growth of human myoblasts in primary cultures, we demonstrated that both CH and CH-HA substrates were able to support the cell growth since they did not affect cell count and DNA synthesis. On the contrary, the degree of myoblast differentiation, assessed as a function of creatine phosphokinase (CPK) activity on living cells, was completely different on the two biomaterials. Indeed, the amount of CPK increased on CH-HA cultured cells as a result of myotube formation, while CH grown myoblasts remained unfused and displayed no increase on the CPK activity even after 12 days culture. Moreover, the expression level of MyoD and myogenin mRNA, both related to myogenic cell differentiation, appeared extremely low in CH-grown cells, while they were rapidly induced in CH-HA cultured myoblasts.

7.
Minerva Stomatol ; 47(10): 553-7, 1998 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-9866970

RESUMO

A clinical and microscopical (SEM) investigation has been carried out on the biocompatibility of cellulose acetate fiber tetracycline with 25% of tetracycline hydrochloride (Actisite R). A subject with advanced periodontal disease was selected and a pocket of 8 mm of PD was chosen. A segment of fiber was inserted into the pocket for 8 days. After removal, PD and GI clinical parameters were detected and the fiber removed was analyzed at the scanning electronic microscope. The results showed clinical signs of inflammation after removal of fiber. SEM analysis showed macrophagic reaction, a typical sign of inflammatory response to material. The study suggests the need of more biocompatible materials, easier to use as delivery system of antibiotics in the treatment of periodontal disease.


Assuntos
Antibacterianos/administração & dosagem , Materiais Biocompatíveis/administração & dosagem , Celulose/análogos & derivados , Celulose/administração & dosagem , Sistemas de Liberação de Medicamentos , Bolsa Periodontal/tratamento farmacológico , Tetraciclina/administração & dosagem , Adulto , Preparações de Ação Retardada , Combinação de Medicamentos , Avaliação de Medicamentos , Humanos , Masculino , Microscopia Eletrônica de Varredura , Bolsa Periodontal/patologia
8.
Minerva Stomatol ; 47(10): 559-64, 1998 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-9866971

RESUMO

The study analyses the possibility of using polyhydroxyethyl methacrylate as a material for the slow release of antibiotic in periodontal pockets. The antibiotics examined were tetracycline and metronidazole. The aim of the study was to evaluate the biocompatibility of the material with periodontal tissue and the efficacy of the 2 prepared systems. Two sites were selected in 2 periodontopathic patients who after non-surgical treatment presented pockets measuring 8 and 7 mm. A sheet of pHEMA containing tetracycline was inserted in one and in the other a sheet containing metronidazole: both were left for 8 days in the chosen pockets. At the start and end of treatment PD and GI clinical indices were measured and the DMDx microbiological test was performed to identify Aa of Pg and Pi. The tissue reaction to pHEMA was evaluated using SEM analysis of two samples collected after 8 days of treatment. The microscopic results showed the optimal biocompatibility of both samples. Differences were noted with regard to clinical and microbiological efficacy. It was observed that the sheet of pHEMA containing tetracycline resulted in the disappearance of bleeding and a reduced depth of survey. Moreover, microbiological results showed a significant reduction in Porphyromonas gingivalis. The sheet of pHEMA containing metronidazole showed a lower level of therapeutic efficacy. Although reduced depth was noted, gingival bleeding was persistent and the reduction of bacteria analysed was not significant. In conclusion, the authors confirm the optimal biocompatibility of the material and its easy application, although further research, especially for pHEMA with metronidazole, must be carried out to improve drug kinetics, trying to maintain an effective local concentration throughout treatment.


Assuntos
Antibacterianos/administração & dosagem , Materiais Biocompatíveis/administração & dosagem , Sistemas de Liberação de Medicamentos , Metronidazol/administração & dosagem , Bolsa Periodontal/tratamento farmacológico , Poli-Hidroxietil Metacrilato/administração & dosagem , Tetraciclina/administração & dosagem , Preparações de Ação Retardada , Combinação de Medicamentos , Avaliação de Medicamentos , Humanos , Microscopia Eletrônica de Varredura , Bolsa Periodontal/patologia
9.
Monaldi Arch Chest Dis ; 53(1): 92-6, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9632916

RESUMO

The central role of macrophages in host defence against infection and malignancy and processes such as atherosclerosis, makes macrophage biology a fascinating area for research in immunology and cell biology. The endocytic and phagocytic machinery of macrophages is particularly potent and their secretory potential is large and diverse. Studies of cell surface receptors and their role in antigen presentation, microbicidal and tumouricidal activity are actively researched and progress is now being made in defining receptors responsible for monocyte/macrophage cell adhesion within the immune system. This short-review highlights the recent advances in macrophage biology.


Assuntos
Macrófagos/imunologia , Monócitos/imunologia , Endocitose , Humanos , Macrófagos Alveolares/imunologia , Óxido Nítrico/imunologia , Fagocitose
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