PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Protein Array Analysis”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,153 records · Page 64Linked to original sources
PubMed2004

Proteomic patterns as a diagnostic tool for early-stage cancer: a review of its progress to a clinically relevant tool.

The pace of development in novel technologies that promise improvements in the early diagnosis of disease is truly impressive. One such technology at the forefront of this revolution is mass spectrometry. New capabilities in mass spectrometry have provided the means for the development of proteomics, and the race is on to find innovative ways to apply this powerful technology to solving the problems faced in clinical medicine. One area that has garnered much attention over the past few years is the use of mass spectral patterns for cancer diagnostics. The use of these so-called 'proteomic patterns' for disease diagnosis relies fundamentally on the pattern of signals observed within a mass spectrum rather than the more conventional identification and quantitation of a biomarker such as in the case of cancer antigen-125- or prostate-specific antigen. The inherent throughput of proteomic pattern technology enables the analysis of hundreds of clinical samples per day. Currently, there are two primary means by which proteomic patterns can be acquired, surface-enhanced laser desorption/ionization (SELDI) and an electrospray ionization (ESI) method that has been popularized under the name, OvaCheck. In this review, an historical perspective on the development of proteomic patterns for the diagnosis of early-stage cancers is described. In addition, a critical assessment of the overall technology is presented with an emphasis on the steps required to enable proteomic pattern analysis to become a viable clinical tool for diagnosing early-stage cancers.

Early Diagnosis↗
PubMed2006

Quantitative proteomics of the archaeon Methanococcus maripaludis validated by microarray analysis and real time PCR.

For the archaeon Methanococcus maripaludis, a fully sequenced and annotated model species of hydrogenotrophic methanogen, we report validation of quantitative protein level expression ratios on a proteome-wide basis. Using an approach based on quantitative multidimensional capillary HPLC and quadrupole ion trap mass spectrometry, coverage of gene expression approached that currently achievable with transcription microarrays. Comprehensive mass spectrometry-based proteomics and spotted cDNA arrays were used to compare global protein and mRNA levels in a wild-type (S2) and mutant strain (S40) of M. maripaludis. Using linear regression with 652 expression ratios generated by both the proteomic and microarray methods, a product moment correlation coefficient of 0.24 was observed. The correlation improved to 0.61 if only genes showing significant expression changes were included. A novel two-stage method of outlier detection was used for the protein measurements when Dixon's Q-test by itself failed to give satisfactory results. The log(2) transformations of the number of peptides or isotopic peptide pairs associated with each ORF, divided by the predicted molecular weight, were found to have moderately positive correlations with two bioinformatic predictors of gene expression based on codon bias. We detected peptides derived from 939 proteins or 55% of the genome coding capacity. Of these, 60 were overexpressed, and 34 were underexpressed in the mutant. Of the 1722 ORFs encoded in the genome, 1597 or 93% were probed by cDNA arrays. Of these, 50 were more highly expressed, and 45 showed lower expression levels in the mutant relative to the wild type. 15 ORFs were shown to be overexpressed by both methods, and two ORFs were shown to be overexpressed by proteomics and underexpressed by microarray.

Archaeal Proteins↗
PubMed2005

Evaluation of two-dimensional electrophoresis and liquid chromatography--tandem mass spectrometry for tissue-specific protein profiling of laser-microdissected plant samples.

Laser microdissection (LM) allows the collection of homogeneous tissue- and cell-specific plant samples. The employment of this technique with subsequent protein analysis has thus far not been reported for plant tissues, probably due to the difficulties associated with defining a reasonable cellular morphology and, in parallel, allowing efficient protein extraction from tissue samples. The relatively large sample amount needed for successful proteome analysis is an additional issue that complicates protein profiling on a tissue- or even cell-specific level. In contrast to transcript profiling that can be performed from very small sample amounts due to efficient amplification strategies, there is as yet no amplification procedure for proteins available. In the current study, we compared different tissue preparation techniques prior to LM/laser pressure catapulting (LMPC) with respect to their suitability for protein retrieval. Cryo-sectioning was identified as the best compromise between tissue morphology and effective protein extraction. After collection of vascular bundles from Arabidopsis thaliana stem tissue by LMPC, proteins were extracted and subjected to protein analysis, either by classical two-dimensional gel electrophoresis (2-DE), or by high-efficiency liquid chromatography (LC) in conjunction with tandem mass spectrometry (MS/MS). Our results demonstrate that both methods can be used with LMPC collected plant material. But because of the significantly lower sample amount required for LC-MS/MS than for 2-DE, the combination of LMPC and LC-MS/MS has a higher potential to promote comprehensive proteome analysis of specific plant tissues.

Arabidopsis↗
PubMed2004

Urine protein profiling with surface-enhanced laser-desorption/ionization time-of-flight mass spectrometry.

BACKGROUND: In the last few years there has been an increasing interest in exploring the human proteome. In particular, efforts have focused on developing strategies to generate reproducible protein maps of normal cells, tissues, and biologic fluids, from which studies can then compare protein expression between different groups (e.g., healthy individuals vs. those with a specific pathologic state). METHODS: Various extrinsic factors (instrument settings, matrix composition, urine storage post void, freeze-thaw cycles) and intrinsic factors (blood in urine, urine dilution, first-void vs. midstream urine) were analyzed with respect to their impact on urine protein profiling using surface-enhanced laser-desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). RESULTS: Extrinsic factors that critically influenced reproducibility and peak detection of urine protein profiling were matrix composition and instrument settings, while freeze-thaw cycles had minimal impact. Midstream urines samples did not undergo changes in their protein profile when stored for three days at 4 degrees C. Intrinsic factors that influenced normal urine protein profiling were blood in the urine and urine dilution. Female first-void urine had a significantly different ratio of proteins present compared to a midstream urine sample. Limitations of the SELDI-TOF-MS technique included ion suppression and quantification of individual proteins when protein composition was complex. CONCLUSION: SELDI-TOF-MS offers a unique platform for high throughput urine protein profiling; however, standardization of analysis conditions is critical, and both extrinsic and intrinsic factors must be taken into account for accurate data interpretation.

Female↗
PubMed2004

VBC-Genomics Bioscience Research GmbH (LLC).

Founded as a spin-off from the University of Vienna in 1999, VBC-GENOMICS Bioscience Research GmbH (LLC) has rapidly gained a strong position within the Austrian biotech scene, based on its success as a service provider in oligonucleotide synthesis and custom sequencing. In research, the company has focused on the development of diagnostic assays based on microarrays. A technical platform for amplification and analysis of DNA has been established and validated in clinical studies. In addition, the company has developed the world's first protein microarray that is certified as an in vitro diagnostic device. This microarray contains allergen components and provides a powerful assay for the profiling of numerous allergy disease-related antigens. The company also markets technological skills and array development expertise to academics and industry.

Biotechnology↗
PubMed2003

Analysis of chicken and turkey ovalbumins by microchip electrophoresis combined with exoglycosidase digestion.

The polypeptide and carbohydrate patterns of two glycoproteins, chicken ovalbumin (CO) and turkey ovalbumin (TO), were analyzed by microchip electrophoresis (ME), following digestion with proteases and exoglycosidases. Glycopeptides derived from ovalbumin were obtained by digestion with Pronase, followed by dialysis, and then separated by ME. Using CO as model, the method was developed to deduce the structure of glycans from glycoproteins by comparing the electropherograms of glycopeptides with and without digestion of exolycosidases. Applying the same approach, the structure of oligosaccharides linked to TO was determined. TO was found to contain high-mannose type oligosaccharides and oligosaccharides with terminal N-acetylglucosamine residues. The complete primary analysis of CO and TO by ME described in this paper provides a basis for an analysis of glycoproteins with an integrated microfluidic chip.

Amino Acid Sequence↗
PubMed2006

[Protein microarray biosensor based on imaging ellipsometry and its biomedical applications].

A protein microarray biosensor based on imaging ellipsometry has been developed as a high-throughput and fast technique for protein analysis. As an automatic technique, it has advanced properties such as label-free, multi-protein simultaneous detection, static or kinetic analysis for protein interaction, and qualitative or quantitative analysis. It has been used for the biomedical applications including tumor markers detection, hepatitis B test, protein competitive adsorption and kinetic visualization for protein interactions. It have demonstrated promising potential for further applications in biomedicine.

Biosensing Techniques↗
PubMed2005

A nondestructive molecule extraction method allowing morphological and molecular analyses using a single tissue section.

In clinical practice, molecular analysis of tumor specimens is often restricted by available technology for sample preparation. Virtually all current methods require homogenization of tissues for molecule extraction. We have developed a simple, rapid, nondestructive molecule extraction (NDME) method to extract proteins and nucleic acids directly from a single fixed or frozen tissue section without destroying the tissue morphology. The NDME method is based upon exposure of micron-thick tissue section to extraction buffer with the help of heating and/or intact physical forces (ultrasound and microwave) to facilitate release of macromolecules into the buffer. The extracted proteins and nucleic acids can be used directly without further purification for downstream SDS-PAGE analysis, immunoblotting, protein array, mass spectra protein profiling, PCR, and RT-PCR reactions. Most importantly, the NDME procedure also serves as an antigen retrieval treatment, so that after NDME, the same tissue section can be used for histopathological analyses, such as H&E staining, immunohistochemistry, and in situ hybridization. Thus, the NDME method allows, for the first time, both histological diagnosis and molecular analysis on a single tissue section, whether it is from frozen or fixed tissue specimens.

Animals↗
PubMed2003

Improved net protein balance, lean mass, and gene expression changes with oxandrolone treatment in the severely burned.

OBJECTIVE: To determine the effects of the anabolic agent oxandrolone on muscle protein and gene expression in severely burned children. SUMMARY BACKGROUND DATA: The authors previously showed that oxandrolone increased net muscle protein synthesis in emaciated burned patients receiving delayed treatment for severe burns. They hypothesized that similar effects would be seen in those treated early after burn. METHODS: Thirty-two severely burned children were enrolled in a prospective randomized trial. Subjects underwent studies to assess leg protein net balance 5 days after the first excision and grafting procedure. Immediately after these studies, treatment with placebo (n = 18) or 0.1 mg/kg oxandrolone (n = 14) twice a day was started. One week after this, another net balance study was performed in each subject. Body weights and total body potassium counting were used to determine body compositional changes. Muscle biopsies were taken 1 week after treatment in oxandrolone subjects to examine gene expression changes with gene array (12,600 genes). RESULTS: Protein net balance did not change in the placebo group, while oxandrolone-treated subjects had a significant improvement. Body weights and fat free mass significantly decreased in the placebo group, while no changes were found in the oxandrolone-treated subjects. Expression changes were seen in 14 genes in the oxandrolone group compared to placebo. Some of these included myosin light chain (+2.7-fold change), tubulin (+2.3), calmodulin (-2.3), and protein phosphatase I inhibitor (-2.8). CONCLUSIONS: Oxandrolone improves protein net balance and lean mass in the severely burned. These changes are associated with increased gene expression for functional muscle proteins.

Amino Acids↗
PubMed2004

Proteomic fingerprints for potential application to early diagnosis of severe acute respiratory syndrome.

BACKGROUND: Definitive early-stage diagnosis of severe acute respiratory syndrome (SARS) is important despite the number of laboratory tests that have been developed to complement clinical features and epidemiologic data in case definition. Pathologic changes in response to viral infection might be reflected in proteomic patterns in sera of SARS patients. METHODS: We developed a mass spectrometric decision tree classification algorithm using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry. Serum samples were grouped into acute SARS (n = 74; <7 days after onset of fever) and non-SARS [n = 1067; fever and influenza A (n = 203), pneumonia (n = 176); lung cancer (n = 29); and healthy controls (n = 659)] cohorts. Diluted samples were applied to WCX-2 ProteinChip arrays (Ciphergen), and the bound proteins were assessed on a ProteinChip Reader (Model PBS II). Bioinformatic calculations were performed with Biomarker Wizard software 3.1.1 (Ciphergen). RESULTS: The discriminatory classifier with a panel of four biomarkers determined in the training set could precisely detect 36 of 37 (sensitivity, 97.3%) acute SARS and 987 of 993 (specificity, 99.4%) non-SARS samples. More importantly, this classifier accurately distinguished acute SARS from fever and influenza with 100% specificity (187 of 187). CONCLUSIONS: This method is suitable for preliminary assessment of SARS and could potentially serve as a useful tool for early diagnosis.

Adolescent↗
PubMed2000

van't Hoff enthalpies without baselines.

Analysis of thermal melting curves represents one important approach for evaluating protein stability and the consequences of amino acid substitution on protein structure. By use of the van't Hoff relationship, the differential melting curve can be robustly fit to only three parameters, two of which are the underlying physical constants of melting temperature (Tm) and van't Hoff enthalpy (deltaHvH). Calculated Tm and deltaHvH values are insensitive to the choice of pre- and post-transition baselines. Consequently, the method accurately computes Tm and deltaHvH for extremely truncated data sets, in the complete absence of baseline information, and for proteins with low melting temperatures, where the traditional direct approach routinely fails. Moreover, agreement between deltaHvH values obtained using points derived from pre- vs. post-transition data provide an independent method for detecting some classes of non-two-state transitions. Finally, fitting of the differential denaturation curve should prove useful for analysis of abbreviated data sets obtained from high throughput array analysis of protein stability.

Cytochrome c Group↗
PubMed2006

A serum proteomic pattern for the detection of colorectal adenocarcinoma using surface enhanced laser desorption and ionization mass spectrometry.

PURPOSE: New serum biomarkers are needed to improve the early detection of colorectal adenocarcinoma. We performed surface enhanced laser desorption and ionization time-of-flight mass spectrometry (SELDI-TOF-MS) to screen for differentially expressed proteins in serum and build a proteomic diagnostic pattern for the detection of colorectal adenocarcinoma to improve the prognosis of patients with this disease. EXPERIMENTAL DESIGN: In an attempt to improve current approaches to the serologic diagnosis of colorectal cancer, we analyzed serum samples from subjects with or without colorectal cancer using SELDI-MS. Using a case-control study design, SELDI-MS profile of serum samples from 74 colorectal adenocarcinoma patients were compared with 48 age-and sex-matched healthy subjects using a ProteinChip reader, PBSII-C. Proteomic MS spectra were generated using IMAC3 chips, and protein peaks clustering and classification analyses were performed to build a proteomic pattern that could differentiate patients with colorectal adenocarcinoma from healthy subjects utilizing Biomarker Wizard and Biomarker Patterns software packages, respectively. The constructed pattern was then used to test an independent set of masked serum samples from 60 colorectal cancer patients and 39 healthy subjects. RESULTS: Among the differentially expressed protein peaks identified by SELDI-MS profiling that had the ability to distinguish between patients and healthy subjects, we determined a minimum set of two protein peaks for system training and for developing a decision classification pattern. Masked analysis of an independent set of serum samples showed the diagnostic pattern could differentiate patients with different stages of colorectal cancer from healthy subjects with a sensitivity of 95.00 percent and specificity of 94.87 percent. CONCLUSION: SELDI-TOF-MS profiling of serum proteins combined with bioinformatics tools can be applied to accurately differentiate patients with colorectal cancer from healthy subjects. The high sensitivity and specificity achieved by the constructed clustering analysis algorithm show great potential for the early detection of colorectal cancer.

Adenocarcinoma↗
PubMed2004

Protein microarray technology and ultraviolet crosslinking combined with mass spectrometry for the analysis of protein-DNA interactions.

To gain insights into complex biological processes, such as transcription and replication, the analysis of protein-DNA interactions and the determination of their sequence requirements are of central importance. In this study, we probed protein microarray technology and ultraviolet crosslinking combined with mass spectrometry (MS) for their practicability to study protein-DNA interactions. We chose as a model system the well-characterized interaction of bacterial replication initiator DnaA with its cognate binding site, the DnaA box. Interactions of DnaA domain 4 with a high-affinity DnaA box (R4) and with a low-affinity DnaA box (R3) were compared. A mutant DnaA domain 4, A440V, was included in the study. DnaA domain 4, wt, spotted onto FAST slides, revealed a strong signal only with a Cy5-labeled, double-stranded, 21-mer oligonucleotide containing DnaA box R4. No signals were obtained when applying the mutant protein. Ultraviolet crosslinking combined with nanoLC/MALDI-TOF MS located the site of interaction to a peptide spanning amino acids 433- 442 of Escherichia coli DnaA. This fragment contains six residues that were identified as being involved in DNA binding by recently published crystal structure and nuclear magnetic resonance (NMR) analysis. In the future, the technologies applied in this study will become important tools for studying protein-DNA interactions.

Amino Acid Sequence↗
PubMed2003

Profiling the progression of cancer: separation of microsomal proteins in MCF10 breast epithelial cell lines using nonporous chromatophoresis.

The heterogeneity of cellular protein expression has stimulated development of separations targeting smaller groups of related proteins rather than entire proteomes. The following work describes the development of a technique for the characterization of membrane subproteomes from five different breast epithelial cell lines. Intact membrane proteins are separated by hydrophobicity in the first dimension using nonporous reversed-phase high-performance liquid chromatography (RP-HPLC) to generate unique chromatographic profiles. Fractions of eluent are further separated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to create distinct banding patterns. This hybrid liquid phase/gel phase method circumvents issues of membrane protein precipitation and provides a simple strategy aimed at isolating and characterizing a traditionally underrepresented protein class. Membrane protein profiles are created that discriminate between microsomal fractions of breast epithelial cells in different stages of neoplastic progression. Proteins are subsequently identified using matrix-assisted laser desorption/ionization - mass spectrometry (MALDI-MS) mass fingerprinting and MALDI-quadrupole time of flight - tandem mass spectrometry (QTOF-MS/MS) peptide sequencing. Furthermore, as this strategy preserves intact protein structure, further characterization can be performed on proteins producing mass fingerprint spectra and fragmentation spectra that did not result in database protein identifications. The coupling of nonporous RP-HPLC with SDS-PAGE provides a useful alternative to two-dimensional PAGE (2-D-PAGE) for membrane protein analysis.

Breast↗
PubMed2003

Protein microarrays: meeting analytical challenges for clinical applications.

Protein microarrays, one emerging class of proteomic technologies, have broad applications for discovery and quantitative analysis. A rapidly expanding use of this technology is the acquisition of information about the posttranslational modifications of proteins reflecting the activity state of signal pathways and networks, and is now employed for the analysis of biopsy samples in clinical trial research.

Animals↗
PubMed2005

Identification of 2 serum biomarkers of renal cell carcinoma by surface enhanced laser desorption/ionization mass spectrometry.

PURPOSE: Surface enhanced laser desorption/ionization mass spectrometry can generate robust information from a small amount of clinical samples such as serum and plasma. In this study we identified novel diagnostic biomarkers of renal cell carcinoma (RCC) by large-scale serum protein profiling using surface enhanced laser desorption/ionization mass spectrometry. MATERIALS AND METHODS: Proteomic spectra were generated by a time of flight mass spectrometer from a set of training samples (21 patients with RCC and 24 healthy volunteers) and another set of validation samples (19 patients with RCC, 20 healthy volunteers and 5 patients with pyelonephritis). Information on the peaks (intensity and m/z) was extracted from the mass spectra using newly developed algorithms, and the Mann-Whitney's U test and linear support vector machine were used to identify the peaks distinguishing RCC samples from the controls. RESULTS: Two peaks with molecular masses of 4,151 and 8,968 m/z were selected as significantly more prominent in RCC samples (p <0.01) among the 3,539 peaks in the range of 3,000 to 30,000 m/z obtained from the training samples. Simultaneous recognition of these 2 biomarkers was shown to have a sensitivity of 89.5% for the diagnosis of RCC and an overall specificity of 80.0% (95% [19 of 20] of healthy volunteers and 20% [1 of 5] of patients with pyelonephritis) in the blinded validation samples, and to allow detection of RCC in stage I (UICC) in 88.9% (16 of 18) of the cases. CONCLUSIONS: We identified 2 serum biomarkers potentially useful for the early diagnosis of RCC. This finding warrants a further large-scale multi-institutional analysis for clinical evaluation of the diagnostic significance of these biomarkers.

Adult↗
PubMed2003

Putting thought to paper: a microARCS protease screen.

In micro-arrayed compound screening (microARCS), an agarose gel is used as a reaction vessel that maintains humidity and compound location as well as being a handling system for reagent addition. Two or more agarose gels may be used to bring test compounds, targets, and reagents together, relying on the pore size of the gel matrix to regulate diffusion of reactants. It is in the microenvironment of the agarose matrix that all the components of an enzymatic reaction interact and result in inhibitable catalytic activity. In an effort to increase the throughput of microARCS-based screens, reduce the effort involved in manipulating agarose gels, and reduce costs, blotter paper was used rather than a second agarose gel to introduce a substrate to a gel containing a target enzyme. In this assay, the matrix of the blotter paper did not prevent the substrate from diffusing into the enzyme gel. The compound density of the microARCS format, the ease of manipulating sheets of paper for reagent addition, and a scheduled protocol for running multiple gels allowed for a throughput capacity of more than 200,000 tests per hour. A protease assay was developed and run in the microARCS format at a rate of 200,000 tests per hour using blotter paper to introduce the substrate. Picks in the primary screen were retested in the microARCS format at a density of 384 compounds per sheet. IC(50) values were confirmed in a 96-well plate format. The screen identified several small molecule inhibitors of the enzyme. The details of the screening format and the analysis of the hits from the screen are presented.

Caco-2 Cells↗