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Differential Protein Expression (differential + protein_expression)
Selected AbstractsDifferential protein expression on the cell surface of colorectal cancer cells associated to tumor metastasisPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 5 2010Jose Luis Luque-García Abstract Progression to metastasis is the critical point in colorectal cancer (CRC) survival. However, the proteome associated to CRC metastasis is very poorly understood at the moment. In this study, we used stable isotope labeling by amino acids in cell culture to compare two CRC cell lines: KM12C and KM12SM, representing poorly versus highly metastatic potential, to find and quantify the differences in protein expression, mostly at the cell surface level. After biotinylation followed by affinity purification, membrane proteins were separated by SDS-PAGE and analyzed using nanoflow LC-ESI-LTQ. A total of 291 membrane and membrane-associated proteins were identified with a p value<0.01, from which 60 proteins were found to be differentially expressed by more than 1.5-fold. We identified a number of cell signaling, CDs, integrins and other cell adhesion molecules (cadherin 17, junction plakoglobin (JUP)) among the most deregulated proteins. They were validated by Western blot, confocal microscopy and flow cytometry analysis. Immunohistochemical analysis of paired tumoral samples confirmed that these differentially expressed proteins were also altered in human tumoral tissues. A good correlation with a major abundance in late tumor stages was observed for JUP and 17-,-hydroxysteroid dehydrogenase type 8 (HSD17B8). Moreover, the combined increase in JUP, occludin and F11 receptor expression together with cadherin 17 expression could suggest a reversion to a more epithelial phenotype in highly metastatic cells. Relevant changes were observed also at the metabolic level in the pentose phosphate pathway and several amino acid transporters. In summary, the identified proteins provide us with a better understanding of the events involved in liver colonization and CRC metastasis. [source] Differential protein expression in hypertrophic heart with and without hypertension in spontaneously hypertensive ratsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 7 2006Xian Jin No abstracts. [source] Differential protein expression in anatomical zones of the prostatePROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 10 2005Helena Lexander Abstract The prostate has three anatomical zones: the peripheral (PZ), the transition (TZ), and the central (CZ) zone. It is proposed that the CZ may be of mesodermal origin, whereas the other two are of endodermal origin. Proteome patterns in the zones were characterized to test for differences. Cells were scraped from macroscopically normal areas of PZ, TZ, and CZ in radical prostatectomy specimens. After exclusion of samples with cancer or prostatic intraepithelial neoplasia, 18,cases remained for analysis. Cells were collected in a medium with protease inhibitors, and the protein material was prepared for two-dimensional gel electrophoresis. The proteins in spots that differed quantitatively between regions were identified via mass spectrometric fingerprinting of tryptic fragments and selected tandem mass spectrometry sequence analysis. Ten proteins with significant zonal differential expression were identified, eight with underexpression in the CZ versus the PZ and the TZ (arginase,II, ATP synthase, cytokeratin,8, lamin,A/C, peroxiredoxin,4, protein disulfide isomerase,A3, tropomyosin, and vimentin), and two with overexpression in the CZ (peroxiredoxin,2 and creatine kinase,B). The PZ and TZ, although differing in terms of incidence of cancer and hyperplasia, have epithelium with highly similar major protein expression profiles. However, the protein profile of the CZ differs from that of the other regions, suggesting functional differences. [source] Differential protein expression in human gliomas and molecular insightsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 4 2005Vaibhav C. Chumbalkar Abstract Gliomas are the most common of the primary intracranial tumors with astrocytomas constituting about 40%. Using clinically and histologically assessed astrocytomas, we have studied their protein profiles using a two-dimensional gel electrophoresis-mass spectrometry approach and identified differentially expressed proteins which may be useful molecular indicators to understand these tumors. Examination of the protein profiles of 27,astrocytoma samples of different grades revealed 72,distinct, differentially expressed proteins belonging to various functional groups such as cytoskeleton and intermediate filament proteins, heat shock proteins (HSPs), enzymes and regulatory proteins. Based on the consistency of their differential expression, 29,distinct proteins could be short-listed and may have a role in the pathology of astrocytomas. Some were found to be differentially expressed in both Grade,III and IV astrocytomas while others were associated with a particular grade. A notable observation was underexpression of Prohibitin, a potential tumor suppressor protein, Rho-GDP dissociation inhibitor, Rho-GDI, a regulator of Rho GTPases and HSPs as well as destabilization of glial fibrillary acidic protein, GFAP, major protein of the glial filaments, in Grade,III malignant tumors. We attempt to explain glioma malignancy and progression in terms of their combined role. [source] Differential protein expression between normal, early-stage, and late-stage myxomatous mitral valves from dogsPROTEOMICS - CLINICAL APPLICATIONS, Issue 12 2009Carla M. R. Lacerda Abstract Valvular heart disease accounts for over 20,000 deaths and 90,000 hospitalizations yearly in the United States. Myxomatous valve disease (MVD) is the most common disease of the mitral valve in humans and dogs. MVD is pathologically identical in these species and its pathogenesis is poorly understood. The objectives of this study were to (i) develop proteomic methodology suitable for analysis of extracellular matrix-rich heart valve tissues and (ii) survey over- and under-expressed proteins that could provide mechanistic clues into the pathogenesis of MVD. Normal, early-stage, and late-stage myxomatous mitral valves from dogs were studied. A shotgun proteomic analysis was used to quantify differential protein expression. Proteins were classified by function and clustered according to differential expression patterns. More than 300 proteins, with 117 of those being differentially expressed, were identified. Hierarchical sample clustering of differential protein profiles showed that early- and late-stage valves were closely related. This finding suggests that proteome changes occur in early degeneration stages and these persist in late stages, characterizing a diseased proteome that is distinct from normal. Shotgun proteome analysis of matrix-rich canine heart valves is feasible, and should be applicable to human heart valves. This study provides a basis for future investigations into the pathogenesis of MVD. [source] Constitutive activation of PI3K-Akt and NF-,B during prostate cancer progression in autochthonous transgenic mouse modelTHE PROSTATE, Issue 3 2005Sanjeev Shukla Abstract BACKGROUND Cancer progression is usually facilitated by independent growth signals that may lead to increased cell survival and evasion of apoptosis. Phosphatidylinositol 3,-OH kinase (PI3K)-Akt and transcription factor NF-,B are important signaling molecules and key survival factors involved in the control of cell proliferation, apoptosis, and oncogenesis. Although PI3K-Akt and NF-,B have been implicated in the development and progression of prostate cancer, expression of these molecules during progression of autochthonous disease has not been elucidated. METHODS Prostate cancer growth and progression in autochthonous transgenic adenocarcinoma of the mouse prostate (TRAMP) mice and male non-transgenic littermates were observed by magnetic resonance imaging (MRI). Expression patterns of PI3K-Akt, NF-,B, I,B, and associated signaling molecules during different stages of cancer progression in these mice were examined by Western blot analysis, electrophoretic mobility shift assay (EMSA), enzyme-linked immunoabsorbent assay (ELISA), kinase assay, and immunohistochemistry. RESULTS Sequential MRI and gross analysis of prostate gland exhibited increasing prostate volume associated with the development and progression of prostatic adenocarcinoma in TRAMP mice, compared to male non-transgenic littermates. Differential protein expression of PI3K, phosphorylated-Akt (Ser473), I,B, and its phosphorylation, IKK kinase activity, NF-,B/p65, p50, DNA binding, and transcriptional-regulated genes, viz., Bcl2, cyclin D1, MMP-9, and VEGF were observed during prostate cancer progression in TRAMP mice, compared to male non-transgenic littermates. Expressions of these molecules were significantly increased during cancer progression observed at 24 and 32 weeks of age. CONCLUSIONS Differential expression pattern of PI3K-Akt, NF-,B and I,B during prostate cancer progression in TRAMP mice suggest that these molecules represent potential molecular targets for prevention and/or therapeutic intervention. © 2005 Wiley-Liss, Inc. [source] Effect of sialic acid content on glycoprotein pI analyzed by two-dimensional electrophoresisELECTROPHORESIS, Issue 17 2010Sílvia Barrabés Abstract 2-DE is broadly used for quantitative analysis of differential protein expression in complex mixtures such as serum samples or cell lysates. PTMs directly influence the 2-DE pattern, and knowledge of the rules of protein separation is required in order to understand the protein distribution in a 2-DE gel. Glycosylation is the most common PTM and can modify both the molecular weight and the pI of a protein. In particular, the effect of charged monosaccharides (mainly sialic acids, SAs) on the 2-DE pattern of a protein is of major interest since changes in sialylation are regularly observed in comparative studies. Little is known about the pI shift of a glycoprotein induced by the presence of SAs, or whether this shift is the same for all glycoproteins. To address this issue, this study examined the influence of SA on the 2-DE pattern of three serum glycoproteins (haptoglobin, ,1-antitrypsin and ribonuclease 1), which N -glycan chains had been previously characterised, and reviewed existing bibliographic data. The SA content of the different glycoforms of a glycoprotein showed a negative linear correlation with the pI, although the slope varied among the studied glycoproteins. We also described a positive correlation between the protein pI and the pI decrease per SA molecule. [source] Proteome analysis of human liver tumor tissue by two-dimensional gel electrophoresis and matrixassisted laser desorption/ionization-mass spectrometry for identification of disease-related proteinsELECTROPHORESIS, Issue 24 2002Jina Kim Abstract Hepatocellular carcinoma (HCC) is a common malignancy worldwide and is a leading cause of death. To contribute to the development and improvement of molecular markers for diagnostics and prognostics and of therapeutic targets for the disease, we have largely expanded the currently available human liver tissue maps and studied the differential expression of proteins in normal and cancer tissues. Reference two-dimensional electrophoresis (2-DE) maps of human liver tumor tissue include labeled 2-DE images for total homogenate and soluble fraction separated on pH 3,10 gels, and also images for soluble fraction separated on pH 4,7 and pH 6,9 gels for a more detailed map. Proteins were separated in the first dimension by isoelectric focusing on immobilized pH gradient (IPG) strips, and by 7.5,17.5% gradient sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gels in the second dimension. Protein identification was done by peptide mass fingerprinting with delayed extraction-matrix assisted laser desorption/ionization-time of flight-mass spectrometry (DE-MALDI-TOF-MS). In total, 212 protein spots (117 spots in pH 4,7 map and 95 spots in pH 6,9) corresponding to 127 different polypeptide chains were identified. In the next step, we analyzed the differential protein expression of liver tumor samples, to find out candidates for liver cancer-associated proteins. Matched pairs of tissues from 11 liver cancer patients were analyzed for their 2-DE profiles. Protein expression was comparatively analyzed by use of image analysis software. Proteins whose expression levels were different by more than three-fold in at least 30% (four) of the patients were further analyzed. Numbers of protein spots overexpressed or underexpressed in tumor tissues as compared with nontumorous regions were 9 and 28, respectively. Among these 37 spots, 1 overexpressed and 15 underexpressed spots, corresponding to 11 proteins, were identified. The physiological significance of the differential expressions is discussed. [source] Microbial interactions and differential protein expression in Staphylococcus aureus ,Candida albicans dual-species biofilmsFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 3 2010Brian M. Peters Abstract The fungal species Candida albicans and the bacterial species Staphylococcus aureus are responsible for a majority of hospital-acquired infections and often coinfect critically ill patients as complicating polymicrobial biofilms. To investigate biofilm structure during polymicrobial growth, dual-species biofilms were imaged with confocal scanning laser microscopy. Analyses revealed a unique biofilm architecture where S. aureus commonly associated with the hyphal elements of C. albicans. This physical interaction may provide staphylococci with an invasion strategy because candidal hyphae can penetrate through epithelial layers. To further understand the molecular mechanisms possibly responsible for previously demonstrated amplified virulence during coinfection, protein expression studies were undertaken. Differential in-gel electrophoresis identified a total of 27 proteins to be significantly differentially produced by these organisms during coculture biofilm growth. Among the upregulated staphylococcal proteins was l -lactate dehydrogenase 1, which confers resistance to host-derived oxidative stressors. Among the downregulated proteins was the global transcriptional repressor of virulence factors, CodY. These findings demonstrate that the hyphae-mediated enhanced pathogenesis of S. aureus may not only be due to physical interactions but can also be attributed to the differential regulation of specific virulence factors induced during polymicrobial growth. Further characterization of the intricate interaction between these pathogens at the molecular level is warranted, as it may aid in the design of novel therapeutic strategies aimed at combating fungal,bacterial polymicrobial infection. [source] Differential expression of skeletal muscle proteins in high-fat diet-fed rats in response to capsaicin feedingPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 15 2010Dong Hyun Kim Abstract In this study, the effects of capsaicin on expression of skeletal muscle proteins in Sprague,Dawley rats fed with a high-fat diet (HFD) were investigated. Rats were fed a HFD with or without capsaicin treatment for 8,wk. After HFD feeding, capsaicin-treated rats weighed an average of 8% less than those of the HFD control group. Gastrocnemius muscle tissue from lean and obese rats with or without capsaicin treatment was arrayed using 2-DE for detection of HFD-associated markers. Proteomic analysis using 2-DE demonstrated that 36 spots from a total of approximately 600 matched spots showed significantly different expression; 27 spots were identified as gastrocnemius muscle proteins that had been altered in response to capsaicin feeding, and 6 spots could not be identified by mass fingerprinting. Expression of various muscle proteins was determined by immunoblot analysis for the determination of molecular mechanisms, whereby capsaicin caused inhibition of adipogenesis. Immunoblot analysis revealed increased uncoupling protein 3 (UCP3) protein expression in HFD-fed rats, whereas contents were reduced with capsaicin treatment. Compared with the HFD control group, capsaicin treatment increased phosphorylation of AMP-activated protein kinase (AMPIC) CP3 and acetyl-CoA carboxylase (ACC). To support this result, we also analyzed in vitro differential protein expression in L6 skeletal muscle cells. These data suggest that the AMPK-ACC-malonyl-CoA metabolic signaling pathway is one of the targets of capsaicin action. To the best of our knowledge, this is the first proteomic study to report on analysis of diet-induced alterations of protein expression that are essential for energy expenditure in rat muscle. [source] Blood-feeding and immunogenic Aedes aegypti saliva proteinsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 10 2010Ladawan Wasinpiyamongkol Abstract Mosquito-transmitted pathogens pass through the insect's midgut (MG) and salivary gland (SG). What occurs in these organs in response to a blood meal is poorly understood, but identifying the physiological differences between sugar-fed and blood-fed (BF) mosquitoes could shed light on factors important in pathogens transmission. We compared differential protein expression in the MGs and SGs of female Aedes aegypti mosquitoes after a sugar- or blood-based diet. No difference was observed in the MG protein expression levels but certain SG proteins were highly expressed only in BF mosquitoes. In sugar-fed mosquitoes, housekeeping proteins were highly expressed (especially those related to energy metabolism) and actin was up-regulated. The immunofluorescence assay shows that there is no disruption of the SG cytoskeletal after the blood meal. We have generated for the first time the 2-DE profiles of immunogenic Ae. aegypti SG BF-related proteins. These new data could contribute to the understanding of the physiological processes that appear during the blood meal. [source] ReSASC: A resampling-based algorithm to determine differential protein expression from spectral count dataPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 6 2010Kristina M. Little Abstract Label-free methods for MS/MS quantification of protein expression are becoming more prevalent as instrument sensitivity increases. Spectral counts (SCs) are commonly used, readily obtained, and increase linearly with protein abundance; however, a statistical framework has been lacking. To accommodate the highly non-normal distribution of SCs, we developed ReSASC (resampling-based significance analysis for spectral counts), which evaluates differential expression between two conditions by pooling similarly expressed proteins and sampling from this pool to create permutation-based synthetic sets of SCs for each protein. At a set confidence level and corresponding p -value cutoff, ReSASC defines a new p -value, p,, as the number of synthetic SC sets with p>pcutoff divided by the total number of sets. We have applied ReSASC to two published SC data sets and found that ReSASC compares favorably with existing methods while being easy to operate and requiring only standard computing resources. [source] Upc2p-associated differential protein expression in Candida albicansPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 20 2009Christopher F. Hoehamer Abstract The gain-of-function mutation G648D in UPC2 causes ERG11 up-regulation and increased fluconazole resistance in Candida albicans. In this study, we performed 2-DE and PMF to identify proteomic alterations in an ERG11 -overexpressing fluconazole-resistant C. albicans clinical isolate compared with its fluconazole-susceptible parent strain. We identified 23 differentially expressed proteins, and among them, seven became differentially expressed in a C. albicans wild-type strain after the introduction of a UPC2 allele carrying this mutation. These Upc2p-regulated proteins may contribute to fluconazole resistance in C. albicans. [source] The mTOR target 4E-BP1 contributes to differential protein expression during normoxia and hypoxia through changes in mRNA translation efficiencyPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 5 2008Michaël G. Magagnin Abstract Hypoxia causes a rapid and sustained inhibition in mRNA translation that is characterized by both a transient phosphorylation of eukaryotic initiation factor 2-alpha (eIF2,) and by inhibition of the mRNA cap binding protein eIF4E via activation of two distinct inhibitory proteins, the mammalian target of rapamycin (mTOR) target 4E-BP1 and the eIF4E transporter 4E-T. Although the importance of eIF2, phosphorylation during hypoxia has been clearly demonstrated, there is little information on the potential relevance of eIF4E regulation. We generated HeLa cells stably expressing a short hairpin interfering RNA (shRNA) against 4E-BP1 and found that despite efficient knockdown, no significant changes occurred in the overall inhibition of mRNA translation during hypoxia. However, using a proteomics approach we identified seven proteins that were exclusively expressed in the 4E-BP1 knockdown cells during both normoxic and hypoxic conditions. Further investigation of the transcriptional and translational regulation of these genes by quantitative RT-PCR indicated that the loss of 4E-BP1 causes a significant increase in the rate of protein synthesis of S100 calcium-binding protein A4 (S100A4) and transgelin 2. These 4E-BP1 regulated proteins have previously been associated with tumor cell motility, invasion and metastasis and may thus contribute to an adverse tumor phenotype. [source] Comparative proteome analyses of maize (Zea mays L.) primary roots prior to lateral root initiation reveal differential protein expression in the lateral root initiation mutant rum1PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 15 2006Yan Liu Abstract The embryonically preformed primary root is the first root type of maize that emerges after germination. In this study the abundant soluble proteins of 2.5-day-old primary roots of wild-type and lateral root mutant rum1 seedlings were compared before the initiation of lateral roots. In CBB-stained 2-D gels, among 350,detected proteins 14 were identified as differentially accumulated (>twofold change; t -test: 95%,significance) in wild-type versusrum1 primary roots. These proteins which were identified via ESI MS/MS are encoded by 12,different genes. Functionally, these proteins are involved in lignin biosynthesis, defense, and the citrate cycle. Nine of these genes were further analyzed at the RNA expression level. This study represents the first comparative proteomic analysis of maize primary roots prior to lateral root initiation and will contribute to a better understanding of the molecular basis of root development in cereals. [source] Modifications in the human T,cell proteome induced by intracellular HIV-1 Tat protein expressionPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue S1 2006Mayte Coiras Abstract The effects of the human immunodeficiency virus type,1 (HIV-1) Tat protein on cellular gene expression were analysed using a Jurkat cell line that was stably transfected with tat,gene in a doxycycline-repressible expression system. Expressed Tat protein (aa,1,101) was proved to present basically a nuclear localisation, and to be fully functional to induce HIV,LTR transactivation. Tat expression also resulted in protection from Tunicamycin-induced apoptosis as determined by DNA staining and TUNEL assays. We applied proteomics methods to investigate changes in differential protein expression in the transfected Jurkat-Tat cells. Protein identification was performed using 2-D DIGE followed by MS analysis. We identified the down-regulation of several cytoskeletal proteins such as actin, ,-tubulin, annexin,II, as well as gelsolin, cofilin and the Rac/Rho-GDI complex. Down-expression of these proteins could be involved in the survival of long-term reservoirs of HIV-infected CD4+ T,cells responsible for continuous viral production. In conclusion, in addition to its role in viral mRNA elongation, the proteomic approach has provided insight into the way that Tat modifies host cell gene expression. [source] Analysis of chicken serum proteome and differential protein expression during development in single-comb White Leghorn hensPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 7 2006San-Yuan Huang Abstract Serum is believed to harbor thousands of distinct proteins that are either actively secreted or leak from various blood cells or tissues. Exploring protein composition in serum may accelerate the discovery of novel protein biomarkers for specific economic traits in livestock species. This study analyzed serum protein composition to establish a 2-DE reference map, and monitored protein dynamics of single-comb White Leghorn hens at 8, 19 and 23,weeks after hatching. A total of 119,CBB-stained and 315,silver-stained serum protein spots were analyzed by MALDI-TOF,MS. Of these, 98,CBB-stained and 94,silver-stained protein spots were significantly matched to existing chicken proteins. The identified spots represented 30,distinctive proteins in the serum of laying hens. To compare protein expression during development, expression levels of 47,protein spots were quantified by relative spot volume with Melanie,3 software. Ten protein spots increased and 3,protein spots decreased as hen age increased. Previous research has suggested that some of these proteins play critical roles in egg production. The differentially expressed proteins with unknown identities will be valuable candidates for further explorations of their roles in egg production of laying hens. [source] Analysis of chicken serum proteome and differential protein expression during development in single-comb White Leghorn hensPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 7 2006San-Yuan Huang No abstracts. [source] Differentially expressed proteins in gastrointestinal stromal tumors with KIT and PDGFRA mutationsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 4 2006Hyun Ju Kang Abstract Most gastrointestinal stromal tumors (GIST) have activating mutations in either KIT or PDGFRA. However, a small subset of GIST lacks either mutation. To investigate the molecular characteristics of GIST according to mutation type, protein expression profiles in 12 GIST (2 cases with PDGFRA mutations, 8 cases with KIT mutations and 2 cases lacking either mutation) were analyzed using 2-DE and MALDI-TOF-MS. Comparative analysis of the respective spot patterns using 2-DE showed that 15 proteins were differently expressed according to the mutation status. Expression levels of septin and heat shock protein (HSP) 27 were increased in GIST with KIT mutations and annexin V was overexpressed in GIST lacking either mutation. Among the 15 proteins, overexpression of 5 proteins [annexin V, high mobility group protein 1 (HMGB1), C13orf2, glutamate dehydrogenase 1 and fibrinogen beta chain] and decreased expression of RoXaN correlated with a higher tumor grade. These findings suggest that differential protein expression can be used as a diagnostic biomarker. Moreover, it may play a role in the development and progression of GIST according to activating mutation type, as these proteins have been shown to be involved in tumor metastasis, apoptosis and immune response. [source] Search for the tumor-related proteins of transition cell carcinoma in Taiwan by proteomic analysisPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 3 2006Kun-Hung Sheng Abstract To better understand the carcinogenesis of bladder cancer in Taiwan, we utilized the proteomic approach to search for potential biomarkers of transitional cell carcinoma,(TCC). Analysis by 2-DE and MS/MS indicated that seven proteins are down-regulated and three proteins up-regulated in grade III samples as compared with those of grade,II. Of these deregulated proteins, fatty acid binding proteins, annexin,V, heat-shock protein,27, and lactate dehydrogenase have been shown to be associated with bladder cancer. Our studies also found altered expression of a group of proteins that have not been documented previously in bladder cancer, including annexin,I, 15-hydroxyprostaglandin dehydrogenase, galectin-1, lysophospholipase and mitochondrial short-chain enoyl-coenzyme,A hydratase,1 precursor. These results illustrate a pattern of differential protein expression between low- and high-grade tumors and it may be utilized as the molecular fingerprinting of a subset of bladder cancers. In addition, the present study provides a valuable resource in the study of pathological mechanisms in cancers of urothelial origin. The immunohistochemical staining of grade,II and III TCC samples with antiserum to annexin,I protein was utilized to confirm that the annexin,I protein is up-regulated in grade,III TCC. [source] Differential protein expression between normal, early-stage, and late-stage myxomatous mitral valves from dogsPROTEOMICS - CLINICAL APPLICATIONS, Issue 12 2009Carla M. R. Lacerda Abstract Valvular heart disease accounts for over 20,000 deaths and 90,000 hospitalizations yearly in the United States. Myxomatous valve disease (MVD) is the most common disease of the mitral valve in humans and dogs. MVD is pathologically identical in these species and its pathogenesis is poorly understood. The objectives of this study were to (i) develop proteomic methodology suitable for analysis of extracellular matrix-rich heart valve tissues and (ii) survey over- and under-expressed proteins that could provide mechanistic clues into the pathogenesis of MVD. Normal, early-stage, and late-stage myxomatous mitral valves from dogs were studied. A shotgun proteomic analysis was used to quantify differential protein expression. Proteins were classified by function and clustered according to differential expression patterns. More than 300 proteins, with 117 of those being differentially expressed, were identified. Hierarchical sample clustering of differential protein profiles showed that early- and late-stage valves were closely related. This finding suggests that proteome changes occur in early degeneration stages and these persist in late stages, characterizing a diseased proteome that is distinct from normal. Shotgun proteome analysis of matrix-rich canine heart valves is feasible, and should be applicable to human heart valves. This study provides a basis for future investigations into the pathogenesis of MVD. [source] Proteomic investigation of the effects of weight loss in the gastrocnemius muscle of wild and NZW rabbits via 2D-electrophoresis and MALDI-TOF MSANIMAL GENETICS, Issue 3 2010A. M. Almeida Summary The study of changes within the key agents regulating metabolism during genetic upgrading because of selection can contribute to an improved understanding of genomic and physiological relationships. This may lead to increased efficiencies in animal production. These changes, regarding energy and protein metabolic saving mechanisms, can be highlighted during food restriction periods. In this study, a 20% weight reduction was induced in two rabbit breeds: New Zealand white, a selected meat producer (Oryctolagus cuniculus cuniculus), and Iberian wild rabbit (Oryctolagus cuniculus algirus), with the aim of determining differential protein expression in the gastrocnemius muscle within control (ad libitum) and restricted diet experimental animal groups, using techniques of two-dimensional gel electrophoresis and peptide mass fingerprinting. Results show that l -lactate dehydrogenase, adenylate kinase, , enolase and , enolase, fructose bisphosphate aldolase A and glyceraldehyde 3-phosphate dehydrogenase, which are enzymes involved in energy metabolism, are differentially expressed in restricted diet experimental animal groups. These enzymes are available to be further tested as relevant biomarkers of weight loss and putative objects of manipulation as a selection tool towards increasing tolerance to weight loss. Similar reasoning could be applied to 2D gel electrophoresis spots corresponding to the important structural proteins tropomyosin , chain and troponin I. Finally, a spot identified as mitochondrial import stimulation factor seems of special interest as a marker of undernutrition, and it may be the object of further studies aiming to better understand its physiological role. [source] | |||||||||||||