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1.
Electrophoresis ; 40(1): 140-150, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30246896

RESUMO

The change of cellular glycosylation is one of the key events in malignant transformation and neoplastic progression, and tumor-related glycosylation alterations are promising targets in both tumor diagnosis and therapy. Both malignant transformation and neoplastic progression are the consequence of gene expression alterations and alterations in protein expression. Micro environmental factors such as extracellular matrix (ECM) also play an important role in their growth and metastasis. Tumor-associated glycans are important biomarker candidates for cancer diagnosis and prognosis, and analytical methods for their detection were developed recently. Glycoproteomics that use mass spectrometry for identification of cancer antigens and structural analysis of glycans play a key role in the investigation of changes of glycosylation during malignant transformation and tumor development and metastasis. Deep understanding of glycan remodeling in cancer and the role of glycosyltransferases that are involved in this process will require a detailed profiling of glycosylation patterns of tumor cells, and corresponding analytical methods for their detection were developed.


Assuntos
Biomarcadores Tumorais , Transformação Celular Neoplásica , Glicoproteínas , Metástase Neoplásica , Animais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/química , Biomarcadores Tumorais/metabolismo , Glicoproteínas/análise , Glicoproteínas/química , Glicoproteínas/metabolismo , Glicosilação , Humanos , Camundongos , Neoplasias/química , Neoplasias/metabolismo
2.
Exp Mol Pathol ; 105(1): 89-97, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29856983

RESUMO

The critical molecular and cellular mechanisms involved in the development and progression of prostate cancer remain elusive. In this report, we demonstrate that normal rat prostate epithelial cells (PEC) undergo spontaneous transformation at high passage (p > 85) evidenced by the acquisition of anchorage independent growth when plated on soft agar and tumorigenicity when injected into immunodeficient mice. In addition, we also report the discovery of a minor subpopulation of spontaneously transformed PEC derived from high passage PEC with the ability to migrate through a layer of 1% agar and form expanding colonies on the underlying plastic substratum. Comparison of these soft agar invasive (SAI) cells with low (p < 35), mid (p36-84) and high passage (p > 85) PEC identified marked differences in cell morphology, proliferation and motility. The SAI subpopulation was more tumorigenic than the high passage anchorage independent cultures from which they were isolated, as manifested by a decreased latency period and an increase in the size of tumors arising in immunodeficient mice. In contrast, low and mid passage cells were unable to grow on soft agar and failed to form tumors when injected into immunodeficient mice. Screening with antibody-based signaling arrays identified several differences in the altered expression levels of signaling proteins between SAI-derived cells and low or high passage PEC, including the up-regulation of EGFR and MAPK-related signaling pathways in SAI-selected cells. In summary, these studies suggest that the SAI assay selects for a novel, highly tumorigenic subpopulation of transformed cells that may represent an early step in the progression of slow growing prostatic carcinomas into more rapidly growing and aggressive tumors.


Assuntos
Separação Celular/métodos , Transformação Celular Neoplásica , Células Epiteliais/citologia , Próstata/citologia , Animais , Movimento Celular , Células Cultivadas , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Receptores ErbB/metabolismo , Sistema de Sinalização das MAP Quinases , Masculino , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Cultura Primária de Células/métodos , Ratos
3.
Photodiagnosis Photodyn Ther ; 15: 115-26, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27431589

RESUMO

Photodynamic therapy (PDT) is a treatment that aims to kill cancer cells by reactive oxygen species, mainly singlet oxygen, produced through light activation of a photosensitiser (PS). Amongst photosensitisers that attracted the most attention in the last decade are cationic and amphiphilic molecules based on porphyrin, chlorin and phthalocyanine structures. Our aim was to join this search for more optimal balance of the lipophilic and hydrophilic moieties in a PS. A new amphiphilic porphyrin, 5-(4-octadecanamidophenyl)-10,15,20-tris(N-methylpyridinium-3-yl)porphyrin trichloride (5) was synthesised and characterised by (1)H NMR, UV-vis and fluorescence spectroscopy, and by MALDI-TOF/TOF spectrometry. In vitro photodynamic activity of 5 was evaluated on HeLa cell lines and compared to the activity of the hydrophilic 5-(4-acetamidophenyl)-10,15,20-tris(N-methylpyridinium-3-yl)porphyrin trichloride (7). Low fluence rate (2mWcm(-2)) of red light (643nm) was used for the activation, and both porphyrins showed a drug dose-response as well as a light dose-response relationship, but the amphiphilic porphyrin was presented with significantly lower IC50 values. The obtained IC50 values for 5 were 1.4µM at 15min irradiation time and 0.7µM when the time of irradiation was 30min, while for 7 these values were 37 and 6 times higher, respectively. These results confirm the importance of the lipophilic component in a PS and show a potential for 5 to be used as a PS in PDT applications.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Neoplasias Experimentais/tratamento farmacológico , Fotoquimioterapia/métodos , Porfirinas/administração & dosagem , Porfirinas/síntese química , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Células HeLa , Humanos , Luz , Neoplasias Experimentais/patologia , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/síntese química , Resultado do Tratamento
4.
Biochim Biophys Acta ; 1860(8): 1786-94, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26827872

RESUMO

BACKGROUND: Image-guided tumor ablation is a technique whereby needle-like applicators are placed directly into solid tumors under guidance typically with computed tomography or ultrasound. Changes in IgG and IgM antibody glycosylation were studied during ablation-induced immune response to cancer, and the use of glycosylation as a biomarker for diagnosis, prognosis and disease treatment was examined. METHODS: Plasma from 27 tumor patients was collected immediately before, after and for 6 months following ablation. IgG and IgM antibodies were isolated by use high-throughput chromatography, and analyzed by hydrophilic liquid chromatography. Thorough identification of glycan structures in each chromatography peak was performed by nano-liquid chromatography electrospray ionization mass spectrometry. RESULTS: Although antibody glycosylation was found to vary with cancer type, discernable patterns of change based on the successful treatment of tumors by ablation were not identified. One patient with renal clear cell carcinoma and poor disease outcome had unexpectedly high amount of oligomannose IgG glycans during the whole period of monitoring. In contrast, IgM antibodies did not follow the same pattern. CONCLUSIONS: These findings suggest that glycosylation patterns are indicative of an immune system that is unable to prevent different types of cancer, rather than products of the immunostimulatory response to the ablation of tumor itself. Analyses of the outcome effect suggested that IgG glycosylation and IgM glycosylation are not associated with tumor ablation. GENERAL SIGNIFICANCE: Present work opens a new way for parallel determination of glycosylation changes of both IgG and IgM antibodies by use of high-throughput methods, and their future use as biomarkers for disease diagnosis and prognosis. This article is part of a Special Issue entitled "Glycans in personalised medicine" Guest Editor: Professor Gordan Lauc.


Assuntos
Anticorpos Antineoplásicos/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Neoplasias , Idoso , Idoso de 80 Anos ou mais , Feminino , Glicosilação , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/patologia , Neoplasias/terapia , Espectrometria de Massa de Íon Secundário
5.
J Oral Pathol Med ; 44(5): 367-77, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25040847

RESUMO

BACKGROUND: Keratocystic odontogenic tumour (KCOT) is a benign, yet aggressive odontogenic tumour. Herein, proteome analysis of KCOT lesions in comparison with control patient-matched tissue unaffected by the disease and with inflammatory odontogenic cysts, namely radicular cysts is presented. METHODS: For the proteomics profiling, two complementary proteomics techniques MALDI-MS/MS and LC-ESI-MS/MS were employed. Potential candidate biomarkers were validated by immunohistochemistry. RESULTS: More than 43 proteins were found to be differentially expressed or up-regulated in KCOT lesions in comparison with patient-matched unaffected oral mucosa. These proteins bear important biological functions and are involved in cell proliferation, cytoskeletal re-organization, transcription, cellular motility and apoptosis. In particular, a number of differentially expressed proteins participate in autocrine regulation and signalization within JNK and p38 MAPK signalling pathways. CONCLUSIONS: Immunohistochemical validation of chosen putative biomarkers revealed axin interaction partner and dorsalization-antagonist (AIDA), known as a protein that blocks activation of JNK signalling pathway, as a differential biomarker for KCOT lesions on an independent cohort of KCOT tissue samples in comparison with most prevalent intra-oseal lesions inflammatory odontogenic cysts.


Assuntos
Biomarcadores Tumorais/metabolismo , Tumores Odontogênicos/metabolismo , Proteoma/metabolismo , Adolescente , Adulto , Idoso , Apoptose/fisiologia , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Proteínas de Transporte/análise , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Estudos de Casos e Controles , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/química , Mucosa Bucal/metabolismo , Tumores Odontogênicos/química , Tumores Odontogênicos/genética , Tumores Odontogênicos/patologia , Proteoma/análise , Proteoma/genética , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massas em Tandem , Adulto Jovem
6.
Mol Cell Proteomics ; 14(3): 471-83, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25527621

RESUMO

A distinct feature of human prostate cancer (PCa) is the development of osteoblastic (bone-forming) bone metastases. Metastatic growth in the bone is supported by factors secreted by PCa cells that activate signaling networks in the tumor microenvironment that augment tumor growth. To better understand these signaling networks and identify potential targets for therapy of bone metastases, we characterized the secretome of a patient-derived xenograft, MDA-PCa-118b (PCa-118b), generated from osteoblastic bone lesion. PCa-118b induces osteoblastic tumors when implanted either in mouse femurs or subcutaneously. To study signaling molecules critical to these unique tumor/microenvironment-mediated events, we performed mass spectrometry on conditioned media of isolated PCa-118b tumor cells, and identified 26 secretory proteins, such as TGF-ß2, GDF15, FGF3, FGF19, CXCL1, galectins, and ß2-microglobulin, which represent both novel and previously published secreted proteins. RT-PCR using human versus mouse-specific primers showed that TGFß2, GDF15, FGF3, FGF19, and CXCL1 were secreted from PCa-118b cells. TGFß2, GDF15, FGF3, and FGF19 function as both autocrine and paracrine factors on tumor cells and stromal cells, that is, endothelial cells and osteoblasts. In contrast, CXCL1 functions as a paracrine factor through the CXCR2 receptor expressed on endothelial cells and osteoblasts. Thus, our study reveals a complex PCa bone metastasis secretome with paracrine and autocrine signaling functions that mediate cross-talk among multiple cell types within the tumor microenvironment.


Assuntos
Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/secundário , Proteínas de Neoplasias/metabolismo , Neoplasias da Próstata/metabolismo , Proteômica/métodos , Microambiente Tumoral , Animais , Neoplasias Ósseas/patologia , Comunicação Celular , Linhagem Celular Tumoral , Meios de Cultivo Condicionados/metabolismo , Humanos , Masculino , Camundongos , Camundongos SCID , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Neoplasias da Próstata/patologia , Transdução de Sinais , Células Estromais/fisiologia
7.
Anal Chem ; 85(17): 8112-20, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23909495

RESUMO

The gel-based proteomic analysis of plasma membranes from rat liver and chemically induced, malignant hepatocellular carcinoma Morris hepatoma 7777 was systematically optimized to yield the maximum number of proteins containing transmembrane domains (TMDs). Incorporation of plasma membrane proteins into a polyacrylamide "tube gel" followed by in-gel digestion of "tube gel" pieces significantly improved detection by electrospray ionization-liquid chromatography-tandem mass spectrometry. Removal of less hydrophobic proteins by washing isolated plasma membranes with 0.1 M sodium carbonate enables detection of a higher number of hydrophobic proteins containing TMDs in both tissues. Subsequent treatment of plasma membranes by a proteolytic enzyme (trypsin) causes the loss of some of the proteins that are detected after washing with sodium carbonate, but it enables the detection of other hydrophobic proteins containing TMDs. Introduction of mass spectrometers with higher sensitivity, higher mass resolution and mass accuracy, and a faster scan rate significantly improved detection of membrane proteins, but the improved sample preparation is still useful and enables detection of additional hydrophobic proteins. Proteolytic predigestion of plasma membranes enables detection of additional hydrophobic proteins and better sequence coverage of TMD-containing proteins in plasma membranes from both tissues.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Membrana Celular/química , Neoplasias Hepáticas Experimentais/diagnóstico , Proteoma/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida , Ratos , Ratos Endogâmicos BUF
8.
J Proteomics ; 76 Spec No.: 79-90, 2012 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-22796065

RESUMO

Strong indications have been presented that dietary poisoning with aristolochic acids (AA) is responsible for Endemic Nephropathy (EN) and AA associated cancer of the upper urinary tract (UUTC). Our recent investigation showed drastic urinary proteome changes in AA treated mice. This study was designed to identify proteome changes associated with AA nephrotoxicity in experimental animal model. The DBA and C57BL mice, which differ in AA sensitivity, were exposed to AA for 4 days. The strategy for urinary, plasma and kidney tissue proteome study of AA exposed and control mice integrated gel-based and in-solution tryptic digestion combined with LC-ESI-MS/MS. To maximize proteome coverage, plasma fractionation scheme was developed and MS compatible sequential tissue extraction procedure was established. Proteomic analyses of urinary, plasma and kidney tissue tryptic digests resulted in identification of several cytoskeletal proteins, as well as proteins involved in kidney development and inflammatory response, that are differentially expressed in both AA exposed and control mice. These proteins are consistent with renal pathogenesis of endotoxicity and cancer. This proteomic strategy could be effectively translated for unbiased discovery of potential biomarkers for EN and associated UUTC in humans. At the same time, these results highlight the significance of AA exposure with EN. This article is part of a Special Issue entitled: Integrated omics.


Assuntos
Ácidos Aristolóquicos/efeitos adversos , Biomarcadores Tumorais , Nefropatias , Rim/metabolismo , Mutagênicos/efeitos adversos , Proteínas de Neoplasias , Proteoma/metabolismo , Neoplasias Urológicas , Animais , Ácidos Aristolóquicos/farmacologia , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/urina , Nefropatias/sangue , Nefropatias/induzido quimicamente , Nefropatias/urina , Masculino , Camundongos , Camundongos Endogâmicos DBA , Mutagênicos/farmacologia , Proteínas de Neoplasias/sangue , Proteínas de Neoplasias/urina , Neoplasias Experimentais , Proteômica/métodos , Neoplasias Urológicas/sangue , Neoplasias Urológicas/induzido quimicamente , Neoplasias Urológicas/urina
9.
J Chromatogr A ; 1239: 1-9, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22520159

RESUMO

Sample displacement chromatography (SDC) in reversed-phase and ion-exchange modes was introduced approximately twenty years ago. This method takes advantage of relative binding affinities of components in a sample mixture. During loading, there is a competition among different sample components for the sorption on the surface of the stationary phase. SDC was first used for the preparative purification of proteins. Later, it was demonstrated that this kind of chromatography can also be performed in ion-exchange, affinity and hydrophobic-interaction mode. It has also been shown that SDC can be performed on monoliths and membrane-based supports in both analytical and preparative scale. Recently, SDC in ion-exchange and hydrophobic interaction mode was also employed successfully for the removal of trace proteins from monoclonal antibody preparations and for the enrichment of low abundance proteins from human plasma. In this review, the principals of SDC are introduced, and the potential for separation of proteins and peptides in micro-analytical, analytical and preparative scale is discussed.


Assuntos
Cromatografia Líquida/métodos , Peptídeos/isolamento & purificação , Proteínas/isolamento & purificação
10.
Electrophoresis ; 32(15): 1970-5, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21732553

RESUMO

S-Adenosylhomocysteine hydrolase (AHCY) deficiency is a rare congenital disorder in methionine metabolism clinically characterized by white matter atrophy, delayed myelination, slowly progressive myopathy, retarded psychomotor development and mildly active chronic hepatitis. In the present study, we utilized a comparative proteomics strategy based on 2-DE/MALDI-MS and LC/ESI-MS to analyze plasma proteins from three AHCY-deficient patients prior to and after receiving dietary treatment designed to alleviate disease symptoms. Obtained results revealed candidate biomarkers for the detection of myopathy specifically associated with AHCY deficiency, such as carbonic anhydrase 3, creatine kinase, and thrombospondin 4. Several proteins mediating T-cell activation and function were identified as well, including attractin and diacylglycerol kinase α. Further validation and functional analysis of identified proteins with clinical value would ensure that these biomarkers make their way into routine diagnosis and management of AHCY deficiency.


Assuntos
Adenosil-Homocisteinase/deficiência , Proteínas Sanguíneas/análise , Erros Inatos do Metabolismo/sangue , Adenosil-Homocisteinase/sangue , Biomarcadores/sangue , Biomarcadores/química , Proteínas Sanguíneas/química , Criança , Pré-Escolar , Cromatografia Líquida , Eletroforese em Gel Bidimensional , Humanos , Lactente , Masculino , Erros Inatos do Metabolismo/enzimologia , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
Curr Protoc Protein Sci ; Chapter 8: 8.7.1-8.7.22, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20814934

RESUMO

Reversed-phase HPLC (RP-HPLC) is one of most important techniques for protein separations and the method of choice for peptide separation. RP-HPLC has been applied on the nano, micro, and analytical scale, and has also been scaled up for preparative purifications, to large industrial scale. Because of its compatibility with mass spectrometry, RP-HPLC is an indispensable tool in proteomic research. With modern instrumentation and columns, complex mixtures of peptides and proteins can be separated at attomolar levels for further analysis. In addition, preparative RP-HPLC is often used for large-scale purification of proteins. This unit provides protocols for packing and testing a column, protein separation by use of gradient or step elution, desalting of protein solutions, and separation of enzymatic digests before mass spectrometric analyses. A protocol is also provided for cleaning, regenerating, and storing reversed-phase chromatography columns.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Proteínas/química , Peptídeos/química
12.
J Proteome Res ; 9(9): 4554-64, 2010 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-20812760

RESUMO

Mitosis is a highly regulated process in which errors can lead to genomic instability, a hallmark of cancer. During this phase of the cell cycle, transcription is silent and RNA translation is inhibited. Thus, mitosis is largely driven by post-translational modification of proteins, including phosphorylation, methylation, ubiquitination, and sumoylation. Here, we show that protein acetylation is prevalent during mitosis. To identify proteins that are acetylated, we synchronized HeLa cells in early prometaphase and immunoprecipitated lysine-acetylated proteins with antiacetyl-lysine antibody. The immunoprecipitated proteins were identified by LC-ESI-MS/MS analysis. These include proteins involved in RNA translation, RNA processing, cell cycle regulation, transcription, chaperone function, DNA damage repair, metabolism, immune response, and cell structure. Immunoprecipitation followed by Western blot analyses confirmed that two RNA processing proteins, eIF4G and RNA helicase A, and several cell cycle proteins, including APC1, anillin, and NudC, were acetylated in mitosis. We further showed that acetylation of APC1 and NudC was enhanced by apicidin treatment, suggesting that their acetylation was regulated by histone deacetylase. Moreover, treating mitotic cells with apicidin or trichostatin A induced spindle abnormalities and cytokinesis failure. These studies suggest that protein acetylation/deacetylation is likely an important regulatory mechanism in mitosis.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Mitose/fisiologia , Processamento Pós-Transcricional do RNA , Acetilação , Proteínas de Ciclo Celular/química , Citocinese/efeitos dos fármacos , DNA/química , DNA/metabolismo , Células HeLa , Humanos , Ácidos Hidroxâmicos/farmacologia , Immunoblotting , Espectrometria de Massas , Microscopia de Fluorescência , Mitose/efeitos dos fármacos , Peptídeos Cíclicos/farmacologia , Proteômica , Frações Subcelulares/química , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo
13.
Exp Hematol ; 38(3): 233-45, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20079801

RESUMO

OBJECTIVE: Microvesicles have been shown to mediate intercellular communication. Previously, we have correlated entry of murine lung-derived microvesicles into murine bone marrow cells with expression of pulmonary epithelial cell-specific messenger RNA (mRNA) in these marrow cells. The present studies establish that entry of lung-derived microvesicles into marrow cells is a prerequisite for marrow expression of pulmonary epithelial cell-derived mRNA. MATERIALS AND METHODS: Murine bone marrow cells cocultured with rat lung, but separated from them using a cell-impermeable membrane (0.4-microm pore size), were analyzed using species-specific primers (for rat or mouse). RESULTS: These studies revealed that surfactant B and C mRNA produced by murine marrow cells were of both rat and mouse origin. Similar results were obtained using murine lung cocultured with rat bone marrow cells or when bone marrow cells were analyzed for the presence of species-specific albumin mRNA after coculture with rat or murine liver. These studies show that microvesicles both deliver mRNA to marrow cells and mediate marrow cell transcription of tissue-specific mRNA. The latter likely underlies the longer-term stable change in genetic phenotype that has been observed. We have also observed microRNA in lung-derived microvesicles, and studies with RNase-treated microvesicles indicate that microRNA negatively modulates pulmonary epithelial cell-specific mRNA levels in cocultured marrow cells. In addition, we have also observed tissue-specific expression of brain, heart, and liver mRNA in cocultured marrow cells, suggesting that microvesicle-mediated cellular phenotype change is a universal phenomena. CONCLUSION: These studies suggest that cellular systems are more phenotypically labile than previously considered.


Assuntos
Células da Medula Óssea/metabolismo , Exossomos/metabolismo , RNA Mensageiro/genética , Transcrição Gênica , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Encéfalo/citologia , Encéfalo/metabolismo , Comunicação Celular/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Grânulos Citoplasmáticos , Fígado/citologia , Fígado/metabolismo , Pulmão/citologia , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/citologia , Miocárdio/metabolismo , Peptídeos/genética , Precursores de Proteínas/genética , Proteolipídeos/genética , Ratos , Ratos Endogâmicos F344
14.
Curr Opin Mol Ther ; 10(2): 116-23, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18386223

RESUMO

Membrane proteins, especially plasma membrane proteins, form one of the most interesting classes of proteins among disease biomarker candidates. Because of their localization on the surface of cells and organelles, membrane proteins also represent potential drug targets. In this review, developments in the characterization of membrane proteins and their role in the treatment of disease, in particular cancer treatment, are presented.


Assuntos
Biomarcadores/análise , Proteínas de Membrana/análise , Humanos , Proteínas de Membrana/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Processamento de Proteína Pós-Traducional
15.
J Chromatogr B Analyt Technol Biomed Life Sci ; 849(1-2): 293-301, 2007 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-16987716

RESUMO

Plasma membranes from normal rat liver and hepatocellular carcinoma Morris hepatoma 7777 were selectively solubilized by use of different reagents. After selective solubilization, proteins were identified by nano-HPLC-electrospray ionization tandem mass spectrometry (LC-ESI MS/MS). Using simple software, the patterns of proteins identified in membrane solubilizates from liver and hepatoma were compared. Proteins identified in Morris hepatoma 7777 and not in the corresponding membrane solubilizate from liver, mostly members of the annexin and heat shock protein families, are discussed as potential candidate markers for hepatocellular carcinomas.


Assuntos
Carcinoma Hepatocelular/metabolismo , Membrana Celular/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Fígado/metabolismo , Proteômica/métodos , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão/métodos , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Octoxinol/química , Proteínas/análise , Proteínas/química , Proteínas/isolamento & purificação , Ratos , Reprodutibilidade dos Testes , Solubilidade , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
16.
Electrophoresis ; 27(13): 2747-58, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16739230

RESUMO

In plasma membrane proteome research, contamination of the isolated plasma membrane fraction with proteins from other organelles is still a problem. Even if highly specific isolation methods are used, such as density gradient centrifugation combined with selective extraction, contaminating proteins cannot be completely removed. To solve this problem, a protocol for the isolation of highly pure plasma membrane fractions from rat liver and two different hepatocellular carcinoma cell lines was developed. Magnetic beads with immobilized mAb's against highly expressed membrane proteins were used for specific binding of membrane vesicles and their separation from other organelles. Isolated plasma membranes were further selectively solubilized with different reagents and analyzed by use of different methods, such as Western blotting, 1- and 2-DE, and MS. Purification and further selective solubilization was validated by use of mAb's against the marker integral plasma membrane protein carcinoembryonic antigen cell adhesion molecule 1, and identification of isolated proteins by MS. The method presented here minimizes contamination with other organelles and enables further identification of membrane proteins.


Assuntos
Anticorpos Monoclonais/química , Fracionamento Celular/métodos , Membrana Celular/química , Óxido Ferroso-Férrico/química , Microesferas , Animais , Linhagem Celular Tumoral , Hepatócitos/química , Fígado/citologia , Proteínas de Membrana/análise , Ratos , Ratos Endogâmicos
17.
Proteomics ; 6(9): 2874-85, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16596706

RESUMO

Inter-alpha inhibitor proteins (IaIp) are a family of structurally related serine protease inhibitors found in relatively high concentrations in human plasma. Recent studies have implicated a role for IaIp in sepsis, and have demonstrated their potential as biomarkers in sepsis and cancer. For characterization of isolated IaI proteins and contaminating proteins during the last steps of the purification process, SELDI-TOF MS and HPLC-ESI-MS/MS were used. After separation by SDS-PAGE or 2-DE, polypeptide bands of 80, 125 and 250 kDa were excised from gels and digested by trypsin. The tryptic peptides were analyzed by both MS methods. The main contamination during the purification process, a band of 80 kDa, contains mainly IaIp heavy chain (HC) H3. HC H1 and H2 were also found in this band. In addition, some vitamin K-dependent clotting factors and inhibitors and other plasma proteins were identified. The 125-kDa band, representing the pre-alpha inhibitor, was found to contain both bikunin and HC H3. The presence of other HC H1, H2 and the recently described HC H4 was also detected by SELDI-TOF MS. The presence of HC H1, H2, and H3 in the 125-kDa band was confirmed by ESI-MS/MS, but not the presence of the H4. Three polypeptides, H1 and H2 together with bikunin, were identified in the 250-kDa band, representing the ITI, by both MS techniques. Once again, the presence of H4 was detected in this band only by SELDI-TOF MS, but the number of corresponding peptides was still not sufficient for final identification of this polypeptide. The importance of the application of proteomic methods for the proper evaluation of therapeutic drugs based on human plasma is discussed.


Assuntos
alfa-Globulinas/isolamento & purificação , Plasma/química , Proteômica , alfa-Globulinas/análise , Sequência de Aminoácidos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Glicoproteínas de Membrana/sangue , Glicoproteínas de Membrana/isolamento & purificação , Dados de Sequência Molecular , Inibidores de Serina Proteinase/sangue , Inibidores de Serina Proteinase/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , Inibidor da Tripsina de Soja de Kunitz/sangue , Inibidor da Tripsina de Soja de Kunitz/isolamento & purificação
18.
J Chromatogr A ; 1123(2): 199-204, 2006 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-16546202

RESUMO

Convective interaction media (CIM) monoliths provide a stationary phase with a high binding capacity for large molecules and are capable of high flow rates at a very low pressure drop. Used as anion- and cation-exchangers or with affinity ligands such as antibodies, these columns have the potential for processing large volumes of complex biological mixtures within a short time. In the present report, monoclonal antibodies against several rat liver plasma membrane proteins were bound and cross-linked to protein A or protein G CIM affinity columns with a bed volume of only 60 microL. Antigens recognized by bound antibodies and co-eluting (interacting) proteins were rapidly isolated in a single step from either total plasma membrane extracts or subfractions isolated using anion-exchange CIM disk-shaped columns. The isolated antigens and co-eluting proteins were subsequently identified by immunoblot or by LC-MS/MS.


Assuntos
Membrana Celular/química , Cromatografia de Afinidade/instrumentação , Proteínas de Membrana/isolamento & purificação , Animais , Antígenos CD/isolamento & purificação , Moléculas de Adesão Celular/isolamento & purificação , Cromatografia de Afinidade/métodos , Cromatografia por Troca Iônica/métodos , Cromatografia Líquida , Dipeptidil Peptidase 4/isolamento & purificação , Fígado/ultraestrutura , Neoplasias Hepáticas Experimentais/química , Espectrometria de Massas , Proteínas do Tecido Nervoso/química , Ratos , Ratos Endogâmicos F344 , Proteína Estafilocócica A/química
19.
J Chromatogr A ; 1123(2): 205-11, 2006 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-16510150

RESUMO

For proteomic analysis, plasma membranes of rat hepatocellular carcinoma Morris hepatoma 7777 were selectively solubilized according to the previously developed method [D. Josic, K. Zeilinger, Methods Enzymol. 271 (1996) 113-134]. If the Triton X100 insoluble pellet is subsequently extracted, several proteins can be solubilized. These proteins can be classified in two groups according to their molecular size. The proteins with apparent molecular weights in SDS-PAGE between 70 and 75 kDa belong to the first group. Smaller proteins, with apparent molecular weights between 30 and 45 kDa, are members of the second group. The main protein of higher molecular weight was also found in the Triton X100 insoluble extract from normal rat liver plasma membranes. This protein was identified as Annexin A6. The proteins from the second group are practically absent in the Triton X100 insoluble extract from rat liver. These proteins are present in relatively high concentrations in plasma membranes of Morris hepatoma 7777. Both groups of detergent-insoluble proteins from Morris hepatoma 7777 were further analyzed with SELDI-TOF and LC electrospray ionization mass spectrometry. From the first group, Annexin A6, together with two other integral plasma membrane proteins, was identified. In the second group of proteins with apparent molecular weights between 30 and 45kDa, further members of the annexin family, Annexins A1, A2, A4, A5 and A7 were identified. The possible role of these low molecular size annexins as potential cancer biomarkers is discussed.


Assuntos
Anexinas/isolamento & purificação , Membrana Celular/química , Neoplasias Hepáticas Experimentais/química , Sequência de Aminoácidos , Animais , Biomarcadores Tumorais/análise , Cálcio/farmacologia , Cromatografia Líquida , Ácido Egtázico/farmacologia , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Dados de Sequência Molecular , Octoxinol , Ratos , Solubilidade , Espectrometria de Massas por Ionização por Electrospray/métodos
20.
Crit Care Med ; 30(3): 617-22, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11990925

RESUMO

OBJECTIVES: The major forms of human inter-alpha-inhibitor proteins circulating in the plasma are inter-alpha-inhibitor (IalphaI, containing one light peptide chain called bikunin and two heavy chains) and pre-alpha-inhibitor (PalphaI, containing one light and one heavy chain). Although it has been reported that a decrease in IalphaI/PalphaI is correlated with an increased mortality rate in septic patients, it remains unknown whether administration of IalphaI/PalphaI early after the onset of sepsis has any beneficial effects on the cardiovascular response and outcome of the septic animal. The aim of this study, therefore, was to determine whether IalphaI and PalphaI have any salutary effects on the depressed cardiovascular function, liver damage, and mortality rate after polymicrobial sepsis. DESIGN: Prospective, controlled, randomized animal study. SETTING: A university research laboratory. SUBJECTS: Male adult rats were subjected to polymicrobial sepsis by cecal ligation and puncture or sham operation followed by the administration of normal saline (i.e., resuscitation). MEASUREMENTS AND MAIN RESULTS: At 1 hr after cecal ligation and puncture, human IalphaI/PalphaI at a dose of 30 mg/kg body weight or vehicle (normal saline, 1 mL/rat) were infused intravenously over a period of 30 mins. At 20 hrs after cecal ligation and puncture (i.e., the late, hypodynamic stage of sepsis), cardiac output was measured by using a dye dilution technique, and blood samples were collected for assessing oxygen content. Oxygen delivery, consumption, and extraction ratio were determined. Plasma concentrations of liver enzymes alanine aminotransferase and aspartate aminotransferase as well as lactate and tumor necrosis factor-alpha also were measured. In additional animals, the necrotic cecum was excised at 20 hrs after cecal ligation and puncture with or without IalphaI/PalphaI treatment, and survival was monitored for 10 days thereafter. The results indicate that administration of human IalphaI/PalphaI early after the onset of sepsis maintained cardiac output and systemic oxygen delivery, whereas it increased oxygen consumption and extraction at 20 hrs after cecal ligation and puncture. The elevated concentrations of alanine aminotransferase, aspartate aminotransferase, tumor necrosis factor-alpha, and lactate were attenuated by IalphaI/PalphaI treatment. In addition, administration of human IalphaI/PalphaI improved the survival rate from 30% to 89% in septic animals at day 10 after cecal ligation and puncture and cecal excision. CONCLUSION: Human IalphaI/PalphaI appears to be a useful agent for maintaining hemodynamic stability and improving survival during the progression of polymicrobial sepsis.


Assuntos
alfa-Globulinas/farmacologia , Hemodinâmica/efeitos dos fármacos , Sepse/tratamento farmacológico , Inibidores de Serina Proteinase/farmacologia , Inibidor da Tripsina de Soja de Kunitz , Análise de Variância , Animais , Débito Cardíaco/efeitos dos fármacos , Humanos , Ácido Láctico/sangue , Masculino , Glicoproteínas de Membrana/farmacologia , Consumo de Oxigênio/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Sepse/fisiopatologia , Análise de Sobrevida , Transaminases/sangue , Transaminases/efeitos dos fármacos , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
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