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1

Survey of Gene Amplifications during Prostate Cancer Progression by High Throughput Fluorescence in Situ Hybridization on Tissue Microarrays  

Microsoft Academic Search

Abstract Prostate cancer development and progression is driven by the accumula- tion of genetic changes, the nature of which remains incompletely understood. To facilitate high-throughput analysis of molecular events taking place in primary, recurrent, and metastatic prostate cancer, we constructed a tissue microarray containing small 0.6-mm cylindrical samples acquired from 371 formalin-fixed blocks, including benign prostatic hyperplasia ( n 5

Lukas Bubendorf; Juha Kononen; Pasi Koivisto; Peter Schraml; Holger Moch; Thomas C. Gasser; Niels Willi; Michael J. Mihatsch; Guido Sauter; Ollip. Kallioniemi

2

Discovering Biological Progression Underlying Microarray Samples  

Microsoft Academic Search

In biological systems that undergo processes such as differentiation, a clear concept of progression exists. We present a novel computational approach, called Sample Progression Discovery (SPD), to discover patterns of biological progression underlying microarray gene expression data. SPD assumes that individual samples of a microarray dataset are related by an unknown biological process (i.e., differentiation, development, cell cycle, disease progression),

Peng Qiu; Andrew J. Gentles; Sylvia K. Plevritis

2011-01-01

3

Statistical Methods for Analyzing Tissue Microarray Data  

Microsoft Academic Search

Tissue microarrays (TMAs) are a new high-throughput tool for the study of protein expression patterns in tissues and are increasingly used to evaluate the diagnostic and prognostic importance of biomarkers. TMA data are rather challenging to analyze. Covariates are highly skewed, non-normal, and may be highly correlated. We present statistical methods for relating TMA data to censored time-to-event data. We

Xueli Liu; Vladimir Minin; Yunda Huang; David B. Seligson; Steve Horvath

2004-01-01

4

A colorful future of quantitative pathology: validation of Vectra technology using chromogenic multiplexed immunohistochemistry and prostate tissue microarrays.  

PubMed

The Vectra platform (Caliper Life Sciences, Hopkinton, MA) is an advanced multispectral imaging system for biomarker quantitation in tissue microarray or intact tissue sections. This is the first study to validate its reliability for quantitating spatially overlapping biomarkers using chromogenic multiplexed immunohistochemistry on prostate tissue microarrays. Two tissue microarray cohorts (an outcome tissue microarray and a progression tissue microarray) were used. The outcome tissue microarray cohort consists of 462 duplicate cores with more than 5-year outcome information. The progression tissue microarray cohort consists of 384 duplicate cores from different disease (stage) groups. The tissue microarray slides were stained with different combinations of antibodies (anti-androgen receptor, anti-E-cadherin, anti-erythroblastosis virus E26 oncogene-related gene product, and anti-?-methylacyl-CoA racemase). Three outcome tissue microarrays were stained with androgen receptor + erythroblastosis virus E26 oncogene-related gene + E-cadherin (outcome tissue microarray 1), androgen receptor + E-cadherin (outcome tissue microarray 2), and erythroblastosis virus E26 oncogene-related gene + E-cadherin (outcome tissue microarray 3), respectively. One progression tissue microarray section was stained with E-cadherin and ?-methylacyl-CoA racemase; tissue microarray slides were then scanned with the Vectra platform. Biomarker expression analysis was performed with Vectra software-Nuance 3.0.0, and inForm 1.2. IBM SPSS Statistics 19 was used for statistical and correlation analysis (SPSS, Chicago, IL). Close concordance was found between the triple- and double-immunostaining assays used for quantitating spatially overlapping biomarkers androgen receptor and erythroblastosis virus E26 oncogene-related gene using outcome tissue microarrays (r = 0.897 for androgen receptor and 0.613 for erythroblastosis virus E26 oncogene-related gene, respectively). ?-Methylacyl-CoA racemase and E-cadherin expression levels measured in progression tissue microarray were consistent with previously published data by other groups. In conclusion, Vectra technology is reliable for objective and high-throughput biomarker quantitation and colocalization study using chromogenic multiplexed immunohistochemistry. PMID:22944297

Huang, Wei; Hennrick, Kenneth; Drew, Sally

2012-08-31

5

Progress in the application of DNA microarrays.  

PubMed Central

Microarray technology has been applied to a variety of different fields to address fundamental research questions. The use of microarrays, or DNA chips, to study the gene expression profiles of biologic samples began in 1995. Since that time, the fundamental concepts behind the chip, the technology required for making and using these chips, and the multitude of statistical tools for analyzing the data have been extensively reviewed. For this reason, the focus of this review will be not on the technology itself but on the application of microarrays as a research tool and the future challenges of the field.

Lobenhofer, E K; Bushel, P R; Afshari, C A; Hamadeh, H K

2001-01-01

6

Tissue Microarray: A rapidly evolving diagnostic and research tool  

PubMed Central

Tissue microarray is a recent innovation in the field of pathology. A microarray contains many small representative tissue samples from hundreds of different cases assembled on a single histologic slide, and therefore allows high throughput analysis of multiple specimens at the same time. Tissue microarrays are paraffin blocks produced by extracting cylindrical tissue cores from different paraffin donor blocks and re-embedding these into a single recipient (microarray) block at defined array coordinates. Using this technique, up to 1000 or more tissue samples can be arrayed into a single paraffin block. It can permit simultaneous analysis of molecular targets at the DNA, mRNA, and protein levels under identical, standardized conditions on a single glass slide, and also provide maximal preservation and use of limited and irreplaceable archival tissue samples. This versatile technique, in which data analysis is automated facilitates retrospective and prospective human tissue studies. It is a practical and effective tool for high-throughput molecular analysis of tissues that is helping to identify new diagnostic and prognostic markers and targets in human cancers, and has a range of potential applications in basic research, prognostic oncology and drug discovery. This article summarizes the technical aspects of tissue microarray construction and sectioning, advantages, application, and limitations.

Jawhar, Nazar M.T.

2009-01-01

7

Tissue Microarray: A rapidly evolving diagnostic and research tool.  

PubMed

Tissue microarray is a recent innovation in the field of pathology. A microarray contains many small representative tissue samples from hundreds of different cases assembled on a single histologic slide, and therefore allows high throughput analysis of multiple specimens at the same time. Tissue microarrays are paraffin blocks produced by extracting cylindrical tissue cores from different paraffin donor blocks and re-embedding these into a single recipient (microarray) block at defined array coordinates. Using this technique, up to 1000 or more tissue samples can be arrayed into a single paraffin block. It can permit simultaneous analysis of molecular targets at the DNA, mRNA, and protein levels under identical, standardized conditions on a single glass slide, and also provide maximal preservation and use of limited and irreplaceable archival tissue samples. This versatile technique, in which data analysis is automated, facilitates retrospective and prospective human tissue studies. It is a practical and effective tool for high-throughput molecular analysis of tissues that is helping to identify new diagnostic and prognostic markers and targets in human cancers, and has a range of potential applications in basic research, prognostic oncology and drug discovery. This article summarizes the technical aspects of tissue microarray construction and sectioning, advantages, application, and limitations. PMID:19318744

Jawhar, Nazar M T

8

The tissue microarray data exchange specification: A community-based, open source tool for sharing tissue microarray data  

Microsoft Academic Search

BACKGROUND: Tissue Microarrays (TMAs) allow researchers to examine hundreds of small tissue samples on a single glass slide. The information held in a single TMA slide may easily involve Gigabytes of data. To benefit from TMA technology, the scientific community needs an open source TMA data exchange specification that will convey all of the data in a TMA experiment in

Jules J Berman; Mary E Edgerton; Bruce A Friedman

2003-01-01

9

Tissue Microarray Applications in Drug Discovery for Pancreatic Cancer  

Microsoft Academic Search

\\u000a The rising incidence of pancreatic cancer combined with limited responses to chemotherapy highlights the need for improved\\u000a molecular characterization in this highly lethal cancer. The discovery and validation of novel biomarkers are urgently needed\\u000a to improve early detection and thereby improve survival outcomes. The introduction and widespread application of tissue microarrays\\u000a (TMAs) over the past decade provide a valuable tool

Aprill Watanabe; Galen Hostetter

10

[New methods in cancer research--tissue microarray].  

PubMed

Cancer research advances imperiously requested for a new reliable method for biomarker tissue localization study, with standardized experimental conditions, reproducible, fast and at low-prices. Tissue Microarrays technique is the most important discovery in histopathology techniques in the last decade. It mainly consists in bringing and precisely organizing in a single paraffin block of hundreds of micro-cylinders from different blocks. Sections from this new block may be processed using almost all analyses (immunohistochemistry, in situ hybridization). The clear sightedness of those who developed this technique is proved by its rapid acceptance and integration in basic research, prognostic factors oncology and drugs discovery, reflected in hundreds of publications. PMID:16610187

Danciu, M; Pl?m?deal?, P; Mihailovici, Maria-Sultana

11

Ontology-based, Tissue MicroArray oriented, image centered tissue bank  

PubMed Central

Background Tissue MicroArray technique is becoming increasingly important in pathology for the validation of experimental data from transcriptomic analysis. This approach produces many images which need to be properly managed, if possible with an infrastructure able to support tissue sharing between institutes. Moreover, the available frameworks oriented to Tissue MicroArray provide good storage for clinical patient, sample treatment and block construction information, but their utility is limited by the lack of data integration with biomolecular information. Results In this work we propose a Tissue MicroArray web oriented system to support researchers in managing bio-samples and, through the use of ontologies, enables tissue sharing aimed at the design of Tissue MicroArray experiments and results evaluation. Indeed, our system provides ontological description both for pre-analysis tissue images and for post-process analysis image results, which is crucial for information exchange. Moreover, working on well-defined terms it is then possible to query web resources for literature articles to integrate both pathology and bioinformatics data. Conclusions Using this system, users associate an ontology-based description to each image uploaded into the database and also integrate results with the ontological description of biosequences identified in every tissue. Moreover, it is possible to integrate the ontological description provided by the user with a full compliant gene ontology definition, enabling statistical studies about correlation between the analyzed pathology and the most commonly related biological processes.

Viti, Federica; Merelli, Ivan; Caprera, Andrea; Lazzari, Barbara; Stella, Alessandra; Milanesi, Luciano

2008-01-01

12

TAMEE: data management and analysis for tissue microarrays  

PubMed Central

Background With the introduction of tissue microarrays (TMAs) researchers can investigate gene and protein expression in tissues on a high-throughput scale. TMAs generate a wealth of data calling for extended, high level data management. Enhanced data analysis and systematic data management are required for traceability and reproducibility of experiments and provision of results in a timely and reliable fashion. Robust and scalable applications have to be utilized, which allow secure data access, manipulation and evaluation for researchers from different laboratories. Results TAMEE (Tissue Array Management and Evaluation Environment) is a web-based database application for the management and analysis of data resulting from the production and application of TMAs. It facilitates storage of production and experimental parameters, of images generated throughout the TMA workflow, and of results from core evaluation. Database content consistency is achieved using structured classifications of parameters. This allows the extraction of high quality results for subsequent biologically-relevant data analyses. Tissue cores in the images of stained tissue sections are automatically located and extracted and can be evaluated using a set of predefined analysis algorithms. Additional evaluation algorithms can be easily integrated into the application via a plug-in interface. Downstream analysis of results is facilitated via a flexible query generator. Conclusion We have developed an integrated system tailored to the specific needs of research projects using high density TMAs. It covers the complete workflow of TMA production, experimental use and subsequent analysis. The system is freely available for academic and non-profit institutions from .

Thallinger, Gerhard G; Baumgartner, Kerstin; Pirklbauer, Martin; Uray, Martina; Pauritsch, Elke; Mehes, Gabor; Buck, Charles R; Zatloukal, Kurt; Trajanoski, Zlatko

2007-01-01

13

Identification of candidate molecular markers of nasopharyngeal Carcinoma by tissue microarray and in situ hybridization  

Microsoft Academic Search

To scan differentially expressed genes and to identify candidate molecular markers in nasopharyngeal carcinoma (NPC), we analyzed\\u000a cDNA microarray data by GenMAPP to find specifically expressed genes in NPC and used tissue microarray and in situ hybridization\\u000a techniques to confirm our microarray results. Our cDNA microarray results showed that TSPAN-1 and DPP10 genes were down-expressed\\u000a in NPC, and COX7B and

Shilong XiongQian; Qian Wang; Lei Zheng; Feng Gao; Junling Li

14

Assessing the application of tissue microarray technology to kidney research.  

PubMed

Tissue microarray (TMA) is a new high-throughput method that enables simultaneous analysis of the profiles of protein expression in multiple tissue samples. TMA technology has not previously been adapted for physiological and pathophysiological studies of rodent kidneys. We have evaluated the validity and reliability of using TMA to assess protein expression in mouse and rat kidneys. A representative TMA block that we have produced included: (1) mouse and rat kidney cortex, outer medulla, and inner medulla fixed with different fixatives; (2) rat kidneys at different stages of development fixed with different fixatives; (3) mouse and rat kidneys with different physiological or pathophysiological treatments; and (4) built-in controls. As examples of the utility, immunostaining for cyclooxygenase-2, renin, Tamm Horsfall protein, aquaporin-2, connective tissue growth factor, and synaptopodin was carried out with kidney TMA slides. Quantitative analysis of cyclooxygense-2 expression in kidneys confirms that individual cores provide meaningful representations comparable to whole-kidney sections. These studies show that kidney TMA technique is a promising and useful tool for investigating the expression profiles of proteins of interest in rodent kidneys under different physiological and pathophysiological conditions. PMID:20086233

Zhang, Ming-Zhi; Su, Yinghao; Yao, Bing; Zheng, Wei; Decaestecker, Mark; Harris, Raymond C

2010-01-19

15

Microarrays  

ERIC Educational Resources Information Center

|Microarrays are revolutionizing genetics by making it possible to genotype hundreds of thousands of DNA markers and to assess the expression (RNA transcripts) of all of the genes in the genome. Microarrays are slides the size of a postage stamp that contain millions of DNA sequences to which single-stranded DNA or RNA can hybridize. This…

Plomin, Robert; Schalkwyk, Leonard C.

2007-01-01

16

Identification of different subtypes of breast cancer using tissue microarray.  

PubMed

Breast cancer may be classified into luminal A, luminal B, HER2+/ER-, basal-like and normal-like subtypes based on gene expression profiling or immunohistochemical (IHC) characteristics. The main aim of the present study was to classify breast cancer into molecular subtypes based on immunohistochemistry findings and correlate the subtypes with clinicopathological factors. Two hundred and seventeen primary breast carcinomas tumor tissues were immunostained for ER, PR, HER2, CK5/6, EGFR, CK8/18, p53 and Ki67 using tissue microarray technique. All subtypes were significantly associated with Malay ethnic background (p=0.035) compared to other racial origins. The most common subtypes of breast cancers were luminal A and was significantly associated with low histological grade (p<0.000) and p53 negativity (p=0.003) compared to HER2+/ER-, basal-like and normal-like subtypes with high histological grade (p<0.000) and p53 positivity (p=0.003). Luminal B subtype had the smallest mean tumor size (p=0.009) and also the highest mean number of lymph nodes positive (p=0.032) compared to other subtypes. All markers except EGFR and Ki67 were significantly associated with the subtypes. The most common histological type was infiltrating ductal carcinoma, NOS. Majority of basal-like subtype showed comedo-type necrosis (68.8%) and infiltrative margin (81.3%). Our studies suggest that IHC can be used to identify the different subtypes of breast cancer and all subtypes were significantly associated with race, mean tumor size, mean number of lymph node positive, histological grade and all immunohistochemical markers except EGFR and Ki67. PMID:21655659

Munirah, M A; Siti-Aishah, M A; Reena, M Z; Sharifah, N A; Rohaizak, M; Norlia, A; Rafie, M K M; Asmiati, A; Hisham, A; Fuad, I; Shahrun, N S; Das, S

2011-01-01

17

Microarray data integration for genome-wide analysis of human tissue-selective gene expression  

PubMed Central

Background Microarray gene expression data are accumulating in public databases. The expression profiles contain valuable information for understanding human gene expression patterns. However, the effective use of public microarray data requires integrating the expression profiles from heterogeneous sources. Results In this study, we have compiled a compendium of microarray expression profiles of various human tissue samples. The microarray raw data generated in different research laboratories have been obtained and combined into a single dataset after data normalization and transformation. To demonstrate the usefulness of the integrated microarray data for studying human gene expression patterns, we have analyzed the dataset to identify potential tissue-selective genes. A new method has been proposed for genome-wide identification of tissue-selective gene targets using both microarray intensity values and detection calls. The candidate genes for brain, liver and testis-selective expression have been examined, and the results suggest that our approach can select some interesting gene targets for further experimental studies. Conclusion A computational approach has been developed in this study for combining microarray expression profiles from heterogeneous sources. The integrated microarray data can be used to investigate tissue-selective expression patterns of human genes.

2010-01-01

18

Outcome Based Screening for Prognostic Phospho-RTK (Receptor Tyrosine Kinase) Antibodies Using Tissue Microarrays.  

National Technical Information Service (NTIS)

Receptor Tyrosine Kinases (RTKs) have been identified as potential targets for both breast cancer prognosis and therapy. We proposed use of tissue microarrays to evaluate the prognostic value of RTKs with emphasis on the phosphorylation status of these re...

D. Rimm

2004-01-01

19

Correspondence Analysis of Genes and Tissue Types and Finding Genetic Links from Microarray Data  

Microsoft Academic Search

In this paper, we propose and use two novel procedures for the analysis of microarray gene expression data. The first is correspondence analysis which visualizes the relationship between genes and tissues as two 2 dimensional graphs, oriented so that distances between genes are preserved, distances between tissues are preserved, and so that genes which primarily distinguish certain types of tissue

Hirohisa Kishino; Peter J. Waddell

2000-01-01

20

Association of E-cadherin, matrix metalloproteinases, and tissue inhibitors of metalloproteinases with the progression and metastasis of hepatocellular carcinoma  

Microsoft Academic Search

Molecular markers can provide additional information to traditional histomorphological evaluation for the assessment of tumor progression and predicting the likelihood of invasion and metastasis in various types of malignancies. We studied the association of E-cadherin, matrix metalloproteinases (MMPs), and tissue inhibitors of metalloproteinase with the progression and metastasis of hepatocellular carcinoma. Tissue microarray including six normal livers, 14 cirrhotic livers,

Zu-hua Gao; Maria S Tretiakova; Wen-hua Liu; Can Gong; Peter D Farris; John Hart

2006-01-01

21

Annotation and query of tissue microarray data using the NCI Thesaurus  

Microsoft Academic Search

BACKGROUND: The Stanford Tissue Microarray Database (TMAD) is a repository of data serving a consortium of pathologists and biomedical researchers. The tissue samples in TMAD are annotated with multiple free-text fields, specifying the pathological diagnoses for each sample. These text annotations are not structured according to any ontology, making future integration of this resource with other biological and clinical data

Nigam H. Shah; Daniel L. Rubin; Inigo Espinosa; Kelli Montgomery; Mark A. Musen

2007-01-01

22

Tissue microarray - a high-throughput molecular analysis in head and neck cancer  

Microsoft Academic Search

With the identification of a number of novel markers having diagnostic, prognostic, and therapeutic signifi- cance, the application of tissue microarray (TMA) has become a valuable tool for validating candidate markers in cancer research. The TMA is a high-throughput tech- nique, which allows large-scale analyses of hundreds of archival clinical tissue samples using the 'array' approach. This paper highlights briefly

Raghu Radhakrishnan; Monica Solomon; Kapaettu Satyamoorthy; Leslie E. Martin; Mark W. Lingen

2008-01-01

23

Framework for Parsing, Visualizing and Scoring Tissue Microarray Images  

Microsoft Academic Search

Increasingly automated techniques for arraying, im- munostaining, and imaging tissue sections led us to design soft- ware for convenient management, display, and scoring. Demand for molecular marker data derived in situ from tissue has driven histology informatics automation to the point where one can en- vision the computer, rather than the microscope, as the primary viewing platform for histopathological scoring

Andrew Rabinovich; Stan Krajewski; Maryla Krajewska; Ahmed Shabaik; Stephen M. Hewitt; Serge J. Belongie; John C. Reed; Jeffrey H. Price

2006-01-01

24

Discovery of tissue-specific exons using comprehensive human exon microarrays  

PubMed Central

Background Higher eukaryotes express a diverse population of messenger RNAs generated by alternative splicing. Large-scale methods for monitoring gene expression must adapt in order to accurately detect the transcript variation generated by this splicing. Results We have designed a high-density oligonucleotide microarray with probesets for more than one million annotated and predicted exons in the human genome. Using these arrays and a simple algorithm that normalizes exon signal to signal from the gene as a whole, we have identified tissue-specific exons from a panel of 16 different normal adult tissues. RT-PCR validation confirms approximately 86% of the predicted tissue-enriched probesets. Pair-wise comparisons between the tissues suggest that as many as 73% of detected genes are differentially alternatively spliced. We also demonstrate how an inclusive exon microarray can be used to discover novel alternative splicing events. As examples, 17 new tissue-specific exons from 11 genes were validated by RT-PCR and sequencing. Conclusion In conjunction with a conceptually simple algorithm, comprehensive exon microarrays can detect tissue-specific alternative splicing events. Our data suggest significant expression outside of known exons and well annotated genes and a high frequency of alternative splicing events. In addition, we identified and validated a number of novel exons with tissue-specific splicing patterns. The tissue map data will likely serve as a valuable source of information on the regulation of alternative splicing.

Clark, Tyson A; Schweitzer, Anthony C; Chen, Tina X; Staples, Michelle K; Lu, Gang; Wang, Hui; Williams, Alan; Blume, John E

2007-01-01

25

Microarray-based gene expression profiles in multiple tissues of the domesticated silkworm, Bombyx mori  

PubMed Central

We designed and constructed a genome-wide microarray with 22,987 70-mer oligonucleotides covering the presently known and predicted genes in the silkworm genome, and surveyed the gene expression in multiple silkworm tissues on day 3 of the fifth instar. Clusters of tissue-prevalent and tissue-specific genes and genes that are differentially expressed in different tissues were identified, and they reflect well major tissue-specific functions on the molecular level. The data presented in this study provide a new resource for annotating the silkworm genome.

Xia, Qingyou; Cheng, Daojun; Duan, Jun; Wang, Genhong; Cheng, Tingcai; Zha, Xingfu; Liu, Chun; Zhao, Ping; Dai, Fangyin; Zhang, Ze; He, Ningjia; Zhang, Liang; Xiang, Zhonghuai

2007-01-01

26

Tissue microarray evaluation of prothymosin-? as a biomarker for human gastric metaplasia and neoplasia  

Microsoft Academic Search

Introduction. Our objective was to determine if prothymosin-?, a marker for gastric metaplasia previously identified in a Helicobacter-induced gastric metaplasia and neoplasia mouse model, shows significant up regulation in human gastric metaplasia and neoplasia compared to the normal gastric mucosa. Methods. Seven tissue microarrays containing a total of 594 cores from 132 patients with gastric cancer were obtained. Each core

C. M. Leys; S. Nomura; E. Montogomery; J. R. Goldenring

2004-01-01

27

Differential Glycan Profiling by Lectin Microarray Targeting Tissue Specimens  

Microsoft Academic Search

Glycome is defined by the glycosylation machinery with which each cell is equipped, and this differs between species. It is evident that cells show drastic change during cell progression and differentiation associated with tumorigenesis and malformation. Histochemical approaches to analyze molecular and cellular dynamics provide useful clues to answering questions about glycan functions associated with pathology. However, development of glyco-biomarker

Atsushi Kuno; Atsushi Matsuda; Yuzuru Ikehara; Hisashi Narimatsu; Jun Hirabayashi

2010-01-01

28

Tissue Microarray Immunohistochemical Detection of Brachyury Is Not a Prognostic Indicator in Chordoma  

PubMed Central

Brachyury is a marker for notochord-derived tissues and neoplasms, such as chordoma. However, the prognostic relevance of brachyury expression in chordoma is still unknown. The improvement of tissue microarray technology has provided the opportunity to perform analyses of tumor tissues on a large scale in a uniform and consistent manner. This study was designed with the use of tissue microarray to determine the expression of brachyury. Brachyury expression in chordoma tissues from 78 chordoma patients was analyzed by immunohistochemical staining of tissue microarray. The clinicopathologic parameters, including gender, age, location of tumor and metastatic status were evaluated. Fifty-nine of 78 (75.64%) tumors showed nuclear staining for brachyury, and among them, 29 tumors (49.15%) showed 1+ (<30% positive cells) staining, 15 tumors (25.42%) had 2+ (31% to 60% positive cells) staining, and 15 tumors (25.42%) demonstrated 3+ (61% to 100% positive cells) staining. Brachyury nuclear staining was detected more frequently in sacral chordomas than in chordomas of the mobile spine. However, there was no significant relationship between brachyury expression and other clinical variables. By Kaplan-Meier analysis, brachyury expression failed to produce any significant relationship with the overall survival rate. In conclusion, brachyury expression is not a prognostic indicator in chordoma.

Schwab, Joseph H.; Nielsen, G. Petur; Choy, Edwin; Ye, Shunan; Zhang, Zhan; Mankin, Henry; Hornicek, Francis J.; Duan, Zhenfeng

2013-01-01

29

Phosphoprotein Stability in Clinical Tissue and Its Relevance for Reverse Phase Protein Microarray Technology  

PubMed Central

Phosphorylated proteins reflect the activity of specific cell signaling nodes in biological kinase protein networks. Cell signaling pathways can be either activated or deactivated depending on the phosphorylation state of the constituent proteins. The state of these kinase pathways reflects the in vivo activity of the cells and tissue at any given point in time. As such, cell signaling pathway information can be extrapolated to infer which phosphorylated proteins/pathways are driving an individual tumor’s growth. Reverse Phase Protein Microarrays (RPMA) are a sensitive and precise platform that can be applied to the quantitative measurement of hundreds of phosphorylated signal proteins from a small sample of tissue. Pre-analytical variability originating from tissue procurement and preservation may cause significant variability and bias in downstream molecular analysis. Depending on the ex vivo delay time in tissue processing, and the manner of tissue handling, protein biomarkers such as signal pathway phosphoproteins will be elevated or suppressed in a manner that does not represent the biomarker levels at the time of excision. Consequently, assessment of the state of these kinase networks requires stabilization, or preservation, of the phosphoproteins immediately post tissue procurement. We have employed reverse phase protein microarray analysis of phosphoproteins to study the factors influencing stability of phosphoproteins in tissue following procurement. Based on this analysis we have established tissue procurement guidelines for clinical research with an emphasis on quantifying phosphoproteins by RPMA.

Espina, Virginia; Mueller, Claudius; Liotta, Lance A.

2013-01-01

30

Identification of candidate molecular markers of nasopharyngeal carcinoma by tissue microarray and in situ hybridization.  

PubMed

To scan differentially expressed genes and to identify candidate molecular markers in nasopharyngeal carcinoma (NPC), we analyzed cDNA microarray data by GenMAPP to find specifically expressed genes in NPC and used tissue microarray and in situ hybridization techniques to confirm our microarray results. Our cDNA microarray results showed that TSPAN-1 and DPP10 genes were down-expressed in NPC, and COX7B and RFC2 genes were over-expressed in NPC. Real-time quantitative reverse transcription-PCR and in situ hybridization (ISH) techniques confirmed that TSPAN-1 and DPP10 genes had only 40.72 and 40.70% positive expression in NPC, but had high positive expression in chronic inflammation of nasopharyngeal mucosa (P < 0.01). However, COX7B and RFC2 genes were high positive rate in NPC (84.24 and 64.53%, respectively) than in normal control tissues. The data suggested that TSPAN-1, DPP10, COX7B and RFC2 genes might be the putative molecular markers of NPC. PMID:21057896

Xiong, Shilong; Wang, Qian; Zheng, Lei; Gao, Feng; Li, Junling

2010-11-05

31

Associations between Notch2, Akt1 and HER2\\/neu Expression in Invasive Human Breast Cancer: A Tissue Microarray Immunophenotypic Analysis on 98 Patients  

Microsoft Academic Search

Objective: We aimed to investigate the existence of associations between well-established and newly recognized biological and phenotypic features of breast cancer involved in tumor progression and prognosis. Methods: Ninety-eight cases of invasive breast cancer were assessed for the immunohistochemical expression of estrogen and progesterone receptors, Ki-67, HER2, Akt-1, and Notch-2, using the tissue microarray technique. Data regarding tumor histotype, histological

Ada Maria Florena; Claudio Tripodo; Carla Guarnotta; Sabrina Ingrao; Rossana Porcasi; Anna Martorana; Giosuè Lo Bosco; Daniela Cabibi; Vito Franco

2007-01-01

32

Microarray Expression Profiles of 20.000 Genes across 23 Healthy Porcine Tissues  

Microsoft Academic Search

BackgroundGene expression microarrays have been intensively applied to screen for genes involved in specific biological processes of interest such as diseases or responses to environmental stimuli. For mammalian species, cataloging of the global gene expression profiles in large tissue collections under normal conditions have been focusing on human and mouse genomes but is lacking for the pig genome.Methodology\\/Principal FindingsHere we

Henrik Hornshøj; Lene Nagstrup Conley; Jakob Hedegaard; Peter Sørensen; Frank Panitz; Christian Bendixen; Jörg Hoheisel

2007-01-01

33

Genome-wide prediction and analysis of human tissue-selective genes using microarray expression data  

PubMed Central

Background Understanding how genes are expressed specifically in particular tissues is a fundamental question in developmental biology. Many tissue-specific genes are involved in the pathogenesis of complex human diseases. However, experimental identification of tissue-specific genes is time consuming and difficult. The accurate predictions of tissue-specific gene targets could provide useful information for biomarker development and drug target identification. Results In this study, we have developed a machine learning approach for predicting the human tissue-specific genes using microarray expression data. The lists of known tissue-specific genes for different tissues were collected from UniProt database, and the expression data retrieved from the previously compiled dataset according to the lists were used for input vector encoding. Random Forests (RFs) and Support Vector Machines (SVMs) were used to construct accurate classifiers. The RF classifiers were found to outperform SVM models for tissue-specific gene prediction. The results suggest that the candidate genes for brain or liver specific expression can provide valuable information for further experimental studies. Our approach was also applied for identifying tissue-selective gene targets for different types of tissues. Conclusions A machine learning approach has been developed for accurately identifying the candidate genes for tissue specific/selective expression. The approach provides an efficient way to select some interesting genes for developing new biomedical markers and improve our knowledge of tissue-specific expression.

2013-01-01

34

Tissue microarray - a high-throughput molecular analysis in head and neck cancer.  

PubMed

With the identification of a number of novel markers having diagnostic, prognostic, and therapeutic significance, the application of tissue microarray (TMA) has become a valuable tool for validating candidate markers in cancer research. The TMA is a high-throughput technique, which allows large-scale analyses of hundreds of archival clinical tissue samples using the 'array' approach. This paper highlights briefly its robust technology, technical aspects of its construction, and the validity of the TMA results for oral pathology diagnostics by reviewing data from recent literature particularly with reference to head and neck cancer. PMID:18251941

Radhakrishnan, Raghu; Solomon, Monica; Satyamoorthy, Kapaettu; Martin, Leslie E; Lingen, Mark W

2008-03-01

35

Microarray analysis of the AHR system: Tissue-specific flexibility in signal and target genes  

SciTech Connect

Data mining published microarray experiments require that expression profiles are directly comparable. We performed linear global normalization on the data of 1967 Affymetrix U74av2 microarrays, i.e. the transcriptomes of > 100 murine tissues or cell types. The mathematical transformation effectively nullifies inter-experimental or inter-laboratory differences between microarrays. The correctness of expression values was validated by quantitative RT-PCR. Using the database we analyze components of the aryl hydrocarbon receptor (AHR) signaling pathway in various tissues. We identified lineage and differentiation specific variant expression of AHR, ARNT, and HIF1{alpha} in the T-cell lineage and high expression of CYP1A1 in immature B cells and dendritic cells. Performing co-expression analysis we found unorthodox expression of the AHR in the absence of ARNT, particularly in stem cell populations, and can reject the hypothesis that ARNT2 takes over and is highly expressed when ARNT expression is low or absent. Furthermore the AHR shows no co-expression with any other transcript present on the chip. Analysis of differential gene expression under 308 conditions revealed 53 conditions under which the AHR is regulated, numerous conditions under which an intrinsic AHR action is modified as well as conditions activating the AHR even in the absence of known AHR ligands. Thus meta-analysis of published expression profiles is a powerful tool to gain novel insights into known and unknown systems.

Frericks, Markus [Institut fuer Umweltmedizinische Forschung (IUF) at the Heinrich Heine-University of Duesseldorf, Auf'm Hennekamp 50, 40225 Duesseldorf (Germany); Meissner, Marc [Institut fuer Umweltmedizinische Forschung (IUF) at the Heinrich Heine-University of Duesseldorf, Auf'm Hennekamp 50, 40225 Duesseldorf (Germany); Esser, Charlotte [Institut fuer Umweltmedizinische Forschung (IUF) at the Heinrich Heine-University of Duesseldorf, Auf'm Hennekamp 50, 40225 Duesseldorf (Germany)]. E-mail: chesser@uni-duesseldorf.de

2007-05-01

36

Datamining Approach for Automation of Diagnosis of Breast Cancer in Immunohistochemically Stained Tissue Microarray Images  

PubMed Central

Cancer of the breast is the second most common human neoplasm, accounting for approximately one quarter of all cancers in females after cervical carcinoma. Estrogen receptor (ER), Progesteron receptor and human epidermal growth factor receptor (HER-2/neu) expressions play an important role in diagnosis and prognosis of breast carcinoma. Tissue microarray (TMA) technique is a high throughput technique which provides a standardized set of images which are uniformly stained, facilitating effective automation of the evaluation of the specimen images. TMA technique is widely used to evaluate hormone expression for diagnosis of breast cancer. If one considers the time taken for each of the steps in the tissue microarray process workflow, it can be observed that the maximum amount of time is taken by the analysis step. Hence, automated analysis will significantly reduce the overall time required to complete the study. Many tools are available for automated digital acquisition of images of the spots from the microarray slide. Each of these images needs to be evaluated by a pathologist to assign a score based on the staining intensity to represent the hormone expression, to classify them into negative or positive cases. Our work aims to develop a system for automated evaluation of sets of images generated through tissue microarray technique, representing the ER expression images and HER-2/neu expression images. Our study is based on the Tissue Microarray Database portal of Stanford university at http://tma.stanford.edu/cgi-bin/cx?n=her1, which has made huge number of images available to researchers. We used 171 images corresponding to ER expression and 214 images corresponding to HER-2/neu expression of breast carcinoma. Out of the 171 images corresponding to ER expression, 104 were negative and 67 were representing positive cases. Out of the 214 images corresponding to HER-2/neu expression, 112 were negative and 102 were representing positive cases. Our method has 92.31% sensitivity and 93.18% specificity for ER expression image classification and 96.67% sensitivity and 88.24% specificity for HER-2/neu expression image classification.

Prasad, Keerthana; Zimmermann, Bernhard; Prabhu, Gopalakrishna; Pai, Muktha

2010-01-01

37

Reduced expression of NGEP is associated with high-grade prostate cancers: a tissue microarray analysis.  

PubMed

New gene expressed in prostate (NGEP) is a newly diagnosed prostate-specific gene that is expressed only in normal prostate and prostate cancer cells. Discovery of tissue-specific markers may promote the development of novel targets for immunotherapy of prostate cancer. In the present study, the staining pattern and clinical significance of NGEP were evaluated in a series of prostate tissues composed of 123 prostate cancer, 19 high-grade prostatic intraepithelial neoplasia and 44 samples of benign prostate tissue included in tissue microarrays using immunohistochemistry. Our study demonstrated that NGEP localized mainly in the apical and lateral membranes and was also partially distributed in the cytoplasm of epithelial cells of normal prostate tissue. All of the examined prostate tissues expressed NGEP with a variety of intensities; the level of expression was significantly more in the benign prostate tissues compared to malignant prostate samples (P value <0.001). Among prostate adenocarcinoma samples, a significant and inverse correlation was observed between the intensity of NGEP expression and increased Gleason score (P = 0.007). Taken together, we found that NGEP protein is widely expressed in low-grade to high-grade prostate adenocarcinomas as well as benign prostate tissues, and the intensity of expression is inversely proportional to the level of malignancy. NGEP could be an attractive target for immune-based therapy of prostate cancer patients as an alternative to the conventional therapies particularly in indolent patients. PMID:23955683

Mohsenzadegan, Monireh; Madjd, Zahra; Asgari, Mojgan; Abolhasani, Maryam; Shekarabi, Mehdi; Taeb, Jaleh; Shariftabrizi, Ahmad

2013-08-17

38

Microarray analysis on archival multiple sclerosis tissue: pathogenic authenticity outweighs technical obstacles.  

PubMed

Probably all neuropathologists know this dilemma: on the one hand, they have extremely precious archival material in their possession, which has been collected over many years from many different laboratories. Typically, this material is extremely well characterized, and often, it contains especially significant tissue specimens from unique cases. On the other hand, they face severe scepticism when they plan to use this archival material for large-scale gene expression studies by microarray analysis, since previous handling in the absence of RNA protection, prolonged storage at room temperature, and fixation with formaldehyde may dramatically reduce the amount of retrievable RNA. Fortunately, this dilemma can be solved. We give here examples from our own, multiple sclerosis-centered laboratory and explain why archival tissue might be more authentic for the disease process and might yield more information about the molecular and cellular substrates driving CNS inflammation in MS patients than more recently acquired tissues. PMID:22188035

Bradl, Monika; Lassmann, Hans

2011-12-22

39

Classification of polycyclic aromatic hydrocarbons based on mutagenicity in lung tissue through DNA microarray.  

PubMed

Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental pollutants produced in the combustion of organic matter. Exposure to PAHs raises the risk of lung cancer and inflammatory and allergic disorders such as asthma. DNA microarray technologies have been applied to research on toxicogenomics in the recent years. To evaluate the mutagenicity of PAHs and constituents of environmental pollutants in lung tissue, including metabolic activation, human alveolar epithelial type II cells (A549) were treated with nonmutagenic PAH pyrene and with the mutagenic PAHs benzo-[a]-pyrene, 1-nitropyrene, or 1,8-dinitropyrene. Comparison of genome-wide microarray expression profiles between a nonmutagenic and a mutagenic PAH-treated group revealed that xenobiotic response genes such as CYP1B1 were commonly upregulated in two groups and that DNA damage induced genes, especially p53-downstream genes such as p21 (CDKN1A) were upregulated only in the mutagenic PAH-treated group. Pretreatment with cytochrome P450 inhibitor ?-naphthoflavone or p53 inhibitor pifithrin-? inhibited the benzo-[a]-pyrene-induced p21 expression. These data suggest that when PAHs enter the cells, lung epithelium induces PAH metabolic activating enzymes, and then the DNA damages-recognition signal is converged with p53 downstream genes. This metabolic activation and DNA damage is induced in lung epithelium, and the mutagenicity of PAHs can be classified by DNA microarray expression profiles. © 2011 Wiley Periodicals, Inc. Environ Toxicol 28:652-659, 2013. PMID:21887816

Hirano, Minoru; Tanaka, Shiho; Asami, Osamu

2011-09-02

40

Use of a mixed tissue RNA design for performance assessments on multiple microarray formats  

PubMed Central

The comparability and reliability of data generated using microarray technology would be enhanced by use of a common set of standards that allow accuracy, reproducibility and dynamic range assessments on multiple formats. We designed and tested a complex biological reagent for performance measurements on three commercial oligonucleotide array formats that differ in probe design and signal measurement methodology. The reagent is a set of two mixtures with different proportions of RNA for each of four rat tissues (brain, liver, kidney and testes). The design provides four known ratio measurements of >200 reference probes, which were chosen for their tissue-selectivity, dynamic range coverage and alignment to the same exemplar transcript sequence across all three platforms. The data generated from testing three biological replicates of the reagent at eight laboratories on three array formats provides a benchmark set for both laboratory and data processing performance assessments. Close agreement with target ratios adjusted for sample complexity was achieved on all platforms and low variance was observed among platforms, replicates and sites. The mixed tissue design produces a reagent with known gene expression changes within a complex sample and can serve as a paradigm for performance standards for microarrays that target other species.

Thompson, Karol L.; Rosenzweig, Barry A.; Pine, P. Scott; Retief, Jacques; Turpaz, Yaron; Afshari, Cynthia A.; Hamadeh, Hisham K.; Damore, Michael A.; Boedigheimer, Michael; Blomme, Eric; Ciurlionis, Rita; Waring, Jeffrey F.; Fuscoe, James C.; Paules, Richard; Tucker, Charles J.; Fare, Thomas; Coffey, Ernest M.; He, Yudong; Collins, Patrick J.; Jarnagin, Kurt; Fujimoto, Susan; Ganter, Brigitte; Kiser, Gretchen; Kaysser-Kranich, Tamma; Sina, Joseph; Sistare, Frank D.

2005-01-01

41

Multi-tissue microarray analysis identifies a molecular signature of regeneration.  

PubMed

The inability to functionally repair tissues that are lost as a consequence of disease or injury remains a significant challenge for regenerative medicine. The molecular and cellular processes involved in complete restoration of tissue architecture and function are expected to be complex and remain largely unknown. Unlike humans, certain salamanders can completely regenerate injured tissues and lost appendages without scar formation. A parsimonious hypothesis would predict that all of these regenerative activities are regulated, at least in part, by a common set of genes. To test this hypothesis and identify genes that might control conserved regenerative processes, we performed a comprehensive microarray analysis of the early regenerative response in five regeneration-competent tissues from the newt Notophthalmus viridescens. Consistent with this hypothesis, we established a molecular signature for regeneration that consists of common genes or gene family members that exhibit dynamic differential regulation during regeneration in multiple tissue types. These genes include members of the matrix metalloproteinase family and its regulators, extracellular matrix components, genes involved in controlling cytoskeleton dynamics, and a variety of immune response factors. Gene Ontology term enrichment analysis validated and supported their functional activities in conserved regenerative processes. Surprisingly, dendrogram clustering and RadViz classification also revealed that each regenerative tissue had its own unique temporal expression profile, pointing to an inherent tissue-specific regenerative gene program. These new findings demand a reconsideration of how we conceptualize regenerative processes and how we devise new strategies for regenerative medicine. PMID:23300656

Mercer, Sarah E; Cheng, Chia-Ho; Atkinson, Donald L; Krcmery, Jennifer; Guzman, Claudia E; Kent, David T; Zukor, Katherine; Marx, Kenneth A; Odelberg, Shannon J; Simon, Hans-Georg

2012-12-26

42

Expression of the AQP-1 water channel in normal human tissues: a semiquantitative study using tissue microarray technology.  

PubMed

Aquaporin water channels are a family of membrane proteins that facilitate water movement across biological membranes. Aquaporin-1 (AQP-1) has been found to be important in osmotic water movement across cell membranes of epithelial and endothelial barriers. However, the distribution of AQP-1 in many normal human tissues is still unknown. The aim of this study was to use immunohistochemistry and semiquantitative histomorphometric analysis to determine the tissue distribution and relative expression of AQP-1 in normal human tissues using tissue microarray (TMA) technology. The normal human TMAs employed in this study included cardiovascular, respiratory, gastrointestinal, hepatic and pancreatobiliary, oral, salivary, nasal, mammary, fetal, endocrine, genital tract, central and peripheral nervous systems, urinary tract, skin, cartilage, and other soft connective tissues. Immunohistochemistry and semiquantitative histomorphometric analysis confirmed the presence of AQP-1 in endothelial barriers of almost all tissues and in many epithelial barriers. AQP-1 was highly expressed in the renal cortex, choroid plexus, and pancreatic ducts. AQP-1 expression levels were surprisingly high in the anus, gallbladder, and liver; moderate expression was also detected in the hippocampus and ependymal cells of the central nervous system. This is the first report of AQP-1 protein distribution in normal human TMAs. These findings confirm the presence of AQP-1 in human endothelia and selected water-transporting epithelia and several new locations, including mammary epithelium, articular chondrocytes, synoviocytes, and synovial microvessels where AQP-1 may be involved in milk production, chondrocyte volume regulation, synovial fluid secretion, and homeostasis, respectively. PMID:14592814

Mobasheri, A; Marples, D

2003-10-30

43

Expression of CXCR4, E-cadherin, Bcl-2, and survivin in Merkel cell carcinoma: an immunohistochemical study using a tissue microarray.  

PubMed

Merkel cell carcinoma (MCC) is a rare but highly aggressive cutaneous malignancy with a mortality rate exceeding that of melanoma. Although smaller studies of markers of progression have been performed, large-scale investigation has been difficult due to the rarity of this tumor. Investigation of 4 potential immunohistochemical progression markers using an MCC tissue microarray was performed. An immunohistochemical analysis of CXCR4, E-cadherin, Bcl-2, and Survivin was performed on a tissue microarray of two hundred twenty-seven 0.6-mm tumor cores-110 primary, 73 local/regional metastatic, and 44 distant metastatic-from 87 patients, 23 of which were sampled 2 or more times. There was a statistically significant increase in immunoreactivity to CXCR4 and Survivin in local/regional nodal MCC metastases compared with primary and distant metastatic lesions. No significant differences by disease location were found for either Bcl-2 or E-cadherin. These results suggest a potential role for CXCR4 and Survivin in MCC tumor progression. However, previous data from other studies suggesting a role for Bcl-2 and E-cadherin in MCC progression are not confirmed in this larger sample. Further discovery of additional markers are needed to better characterize this rare but deadly malignancy. PMID:22814318

Knapp, Charles F; Sayegh, Zena; Schell, Michael J; Rawal, Bhupendra; Ochoa, Tatiana; Sondak, Vernon K; Messina, Jane L

2012-08-01

44

Associations between Selected Biomarkers and Prognosis in a Population-Based Pancreatic Cancer Tissue Microarray  

PubMed Central

Pancreatic cancer is the fourth leading cause of cancer death in the United States. Prognostic biomarkers are lacking, and treatment has limited effect on survival. Tissues from Surveillance, Epidemiology, and End Results registries (Iowa, Hawaii, and Los Angeles) were used to build a tissue microarray of 161 pancreatic tumors (113 resections and 48 biopsies). Proportional hazard models adjusted for age, race, sex, stage, time-period of diagnosis, and treatment. Associations were examined between markers (MUC1, MUC2, MUC5AC, synaptophysin, chromogranin, neuron specific enolase, epidermal growth factor receptor, HER2, CD5, CD138, CK5/6, CK19, CK20, and p53) and survival time from diagnosis. After adjusting for covariates, borderline statistically significant associations were seen between expression of each of the three mucins (MUC1, MUC2, and MUC5AC) and shorter survival time. The associations strengthened for 154 (96%) adenocarcinomas, particularly the 120 (75%) well-differentiated to moderately differentiated ductal adenocarcinomas, a tumor type that occurred more often in the cohort among White cases than cases of other racial origin (P < 0.01). For differentiated ductal adenocarcinomas, associations with shorter survival time were seen for expression of all three mucins combined versus other mucin expression patterns (adjusted hazard ratio, 1.8; 95% confidence interval, 1.2–2.6) and for MUC2(+) versus MUC2(?) expression (adjusted hazard ratio, 1.6; 95% confidence interval, 1.1–2.4). Mucin gene expression, particularly MUC2 expression, may have prognostic value for differentiated adenocarcinomas. Tumor histologies differed in this and Japanese cohorts. The tissue microarray is available to evaluate other biomarkers. Tissue-based surveillance can be used to monitor tumor histology in populations and facilitate applied research.

Takikita, Mikiko; Altekruse, Sean; Lynch, Charles F.; Goodman, Mark T.; Hernandez, Brenda Y.; Green, Mark; Cozen, Wendy; Cockburn, Myles; Saber, Maria Sibug; Topor, Marie; Zeruto, Chris; Abedi-Ardekani, Behnoush; Reichman, Marsha E.; Hewitt, Stephen M.

2009-01-01

45

Quantitative analysis of p53 expression in human normal and cancer tissue microarray with global normalization method  

PubMed Central

Tissue microarray based immunohistochemical staining and proteomics are important tools to create and validate clinically relevant cancer biomarkers. Immunohistochemical stains using formalin-fixed tissue microarray sections for protein expression are scored manually and semi-quantitatively. Digital image analysis methods remove some of the drawbacks of manual scoring but may need other methods such as normalization to provide across the board utility. In the present study, quantitative proteomics-based global normalization method was used to evaluate its utility in the analysis of p53 protein expression in mixed human normal and cancer tissue microarray. Global normalization used the mean or median of ?-actin to calculate ratios of individual core stain intensities, then log transformed the ratios, calculate a mean or median and subtracted the value from the log of ratios. In the absence of global normalization of p53 protein expression, 44% (42 of 95) of tissue cores were positive using the median of intensity values and 40% (38 of 95) using the mean of intensities as cut-off points. With global normalization, p53 positive cores changed to 20% (19 of 95) when using median of intensities and 15.8%(15 of 95) when the mean of intensities were used. In conclusion, the global normalization method helped to define positive p53 staining in the tissue microarray set used. The method used helped to define clear cut-off points and confirmed all negatively stained tissue cores. Such normalization methods should help to better define clinically useful biomarkers.

Idikio, Halliday A

2011-01-01

46

Production of Tissue Microarrays, Immunohistochemistry Staining and Digitalization Within the Human Protein Atlas  

PubMed Central

The tissue microarray (TMA) technology provides the means for high-throughput analysis of multiple tissues and cells. The technique is used within the Human Protein Atlas project for global analysis of protein expression patterns in normal human tissues, cancer and cell lines. Here we present the assembly of 1 mm cores, retrieved from microscopically selected representative tissues, into a single recipient TMA block. The number and size of cores in a TMA block can be varied from approximately forty 2 mm cores to hundreds of 0.6 mm cores. The advantage of using TMA technology is that large amount of data can rapidly be obtained using a single immunostaining protocol to avoid experimental variability. Importantly, only limited amount of scarce tissue is needed, which allows for the analysis of large patient cohorts 1 2. Approximately 250 consecutive sections (4 ?m thick) can be cut from a TMA block and used for immunohistochemical staining to determine specific protein expression patterns for 250 different antibodies. In the Human Protein Atlas project, antibodies are generated towards all human proteins and used to acquire corresponding protein profiles in both normal human tissues from 144 individuals and cancer tissues from 216 different patients, representing the 20 most common forms of human cancer. Immunohistochemically stained TMA sections on glass slides are scanned to create high-resolution images from which pathologists can interpret and annotate the outcome of immunohistochemistry. Images together with corresponding pathology-based annotation data are made publically available for the research community through the Human Protein Atlas portal (www.proteinatlas.org) (Figure 1) 3 4. The Human Protein Atlas provides a map showing the distribution and relative abundance of proteins in the human body. The current version contains over 11 million images with protein expression data for 12.238 unique proteins, corresponding to more than 61% of all proteins encoded by the human genome.

Kampf, Caroline; Olsson, IngMarie; Ryberg, Urban; Sjostedt, Evelina; Ponten, Fredrik

2012-01-01

47

Production of tissue microarrays, immunohistochemistry staining and digitalization within the human protein atlas.  

PubMed

The tissue microarray (TMA) technology provides the means for high-throughput analysis of multiple tissues and cells. The technique is used within the Human Protein Atlas project for global analysis of protein expression patterns in normal human tissues, cancer and cell lines. Here we present the assembly of 1 mm cores, retrieved from microscopically selected representative tissues, into a single recipient TMA block. The number and size of cores in a TMA block can be varied from approximately forty 2 mm cores to hundreds of 0.6 mm cores. The advantage of using TMA technology is that large amount of data can rapidly be obtained using a single immunostaining protocol to avoid experimental variability. Importantly, only limited amount of scarce tissue is needed, which allows for the analysis of large patient cohorts (1 2). Approximately 250 consecutive sections (4 ?m thick) can be cut from a TMA block and used for immunohistochemical staining to determine specific protein expression patterns for 250 different antibodies. In the Human Protein Atlas project, antibodies are generated towards all human proteins and used to acquire corresponding protein profiles in both normal human tissues from 144 individuals and cancer tissues from 216 different patients, representing the 20 most common forms of human cancer. Immunohistochemically stained TMA sections on glass slides are scanned to create high-resolution images from which pathologists can interpret and annotate the outcome of immunohistochemistry. Images together with corresponding pathology-based annotation data are made publically available for the research community through the Human Protein Atlas portal (www.proteinatlas.org) (Figure 1) (3 4). The Human Protein Atlas provides a map showing the distribution and relative abundance of proteins in the human body. The current version contains over 11 million images with protein expression data for 12.238 unique proteins, corresponding to more than 61% of all proteins encoded by the human genome. PMID:22688270

Kampf, Caroline; Olsson, Ingmarie; Ryberg, Urban; Sjöstedt, Evelina; Pontén, Fredrik

2012-05-31

48

Unusual Intron Conservation near Tissue-Regulated Exons Found by Splicing Microarrays  

PubMed Central

Alternative splicing contributes to both gene regulation and protein diversity. To discover broad relationships between regulation of alternative splicing and sequence conservation, we applied a systems approach, using oligonucleotide microarrays designed to capture splicing information across the mouse genome. In a set of 22 adult tissues, we observe differential expression of RNA containing at least two alternative splice junctions for about 40% of the 6,216 alternative events we could detect. Statistical comparisons identify 171 cassette exons whose inclusion or skipping is different in brain relative to other tissues and another 28 exons whose splicing is different in muscle. A subset of these exons is associated with unusual blocks of intron sequence whose conservation in vertebrates rivals that of protein-coding exons. By focusing on sets of exons with similar regulatory patterns, we have identified new sequence motifs implicated in brain and muscle splicing regulation. Of note is a motif that is strikingly similar to the branchpoint consensus but is located downstream of the 5? splice site of exons included in muscle. Analysis of three paralogous membrane-associated guanylate kinase genes reveals that each contains a paralogous tissue-regulated exon with a similar tissue inclusion pattern. While the intron sequences flanking these exons remain highly conserved among mammalian orthologs, the paralogous flanking intron sequences have diverged considerably, suggesting unusually complex evolution of the regulation of alternative splicing in multigene families.

Sugnet, Charles W; Srinivasan, Karpagam; Clark, Tyson A; O'Brien, Georgeann; Cline, Melissa S; Wang, Hui; Williams, Alan; Kulp, David; Blume, John E; Haussler, David; Ares, Manuel

2006-01-01

49

Network screening of Goto-Kakizaki rat liver microarray data during diabetic progression  

PubMed Central

Background Type 2 diabetes mellitus (T2DM) is a complex systemic disease, with significant disorders of metabolism. The liver, a central energy metabolic organ, plays a critical role in the development of diabetes. Although gene expression levels are able to be measured via microarray since 1996, it is difficult to evaluate the contributions of one altered gene expression to a specific disease. One of the reasons is that a whole network picture responsible for a specific phase of diabetes is missing, while a single gene has to be put into a network picture to evaluate its importance. In the aim of identifying significant transcriptional regulatory networks in the liver contributing to diabetes, we have performed comprehensive active regulatory network survey by network screening in 4 weeks (w), 8-12 w, and 18-20 w Goto-Kakizaki (GK) rat liver microarray data. Results We identify active regulatory networks in GK rat by network screening in the following procedure. First, the regulatory networks are compiled by using the known binary relationships between the transcriptional factors and their regulated genes and the biological classification scheme, and second, the consistency of each regulatory network with the microarray data measured in GK rat is estimated to detect the active networks under the corresponding conditions. The comprehensive survey of the consistency between the networks and the measured data by the network screening approach in the case of non-insulin dependent diabetes in the GK rat reveals: 1. More pathways are active during inter-middle stage diabetes; 2. Inflammation, hypoxia, increased apoptosis, decreased proliferation, and altered metabolism are characteristics and display as early as 4weeks in GK strain; 3. Diabetes progression accompanies insults and compensations; 4. Nuclear receptors work in concert to maintain normal glycemic robustness system. Conclusion Notably this is the first comprehensive network screening study of non-insulin dependent diabetes in the GK rat based on high throughput data of the liver. Several important pathways have been revealed playing critical roles in the diabetes progression. Our findings also implicate that network screening is able to help us understand complex disease such as diabetes, and demonstrate the power of network systems biology approach to elucidate the essential mechanisms which would escape conventional single gene-based analysis.

2011-01-01

50

TMA Navigator: Network inference, patient stratification and survival analysis with tissue microarray data.  

PubMed

Tissue microarrays (TMAs) allow multiplexed analysis of tissue samples and are frequently used to estimate biomarker protein expression in tumour biopsies. TMA Navigator (www.tmanavigator.org) is an open access web application for analysis of TMA data and related information, accommodating categorical, semi-continuous and continuous expression scores. Non-biological variation, or batch effects, can hinder data analysis and may be mitigated using the ComBat algorithm, which is incorporated with enhancements for automated application to TMA data. Unsupervised grouping of samples (patients) is provided according to Gaussian mixture modelling of marker scores, with cardinality selected by Bayesian information criterion regularization. Kaplan-Meier survival analysis is available, including comparison of groups identified by mixture modelling using the Mantel-Cox log-rank test. TMA Navigator also supports network inference approaches useful for TMA datasets, which often constitute comparatively few markers. Tissue and cell-type specific networks derived from TMA expression data offer insights into the molecular logic underlying pathophenotypes, towards more effective and personalized medicine. Output is interactive, and results may be exported for use with external programs. Private anonymous access is available, and user accounts may be generated for easier data management. PMID:23761446

Lubbock, Alexander L R; Katz, Elad; Harrison, David J; Overton, Ian M

2013-06-12

51

A metadata-aware application for remote scoring and exchange of tissue microarray images  

PubMed Central

Background The use of tissue microarrays (TMA) and advances in digital scanning microscopy has enabled the collection of thousands of tissue images. There is a need for software tools to annotate, query and share this data amongst researchers in different physical locations. Results We have developed an open source web-based application for remote scoring of TMA images, which exploits the value of Microsoft Silverlight Deep Zoom to provide a intuitive interface for zooming and panning around digital images. We use and extend existing XML-based standards to ensure that the data collected can be archived and that our system is interoperable with other standards-compliant systems. Conclusion The application has been used for multi-centre scoring of TMA slides composed of tissues from several Phase III breast cancer trials and ten different studies participating in the International Breast Cancer Association Consortium (BCAC). The system has enabled researchers to simultaneously score large collections of TMA and export the standardised data to integrate with pathological and clinical outcome data, thereby facilitating biomarker discovery.

2013-01-01

52

Identification of novel tissue-specific genes by analysis of microarray databases: a human and mouse model.  

PubMed

Understanding the tissue-specific pattern of gene expression is critical in elucidating the molecular mechanisms of tissue development, gene function, and transcriptional regulations of biological processes. Although tissue-specific gene expression information is available in several databases, follow-up strategies to integrate and use these data are limited. The objective of the current study was to identify and evaluate novel tissue-specific genes in human and mouse tissues by performing comparative microarray database analysis and semi-quantitative PCR analysis. We developed a powerful approach to predict tissue-specific genes by analyzing existing microarray data from the NCBI's Gene Expression Omnibus (GEO) public repository. We investigated and confirmed tissue-specific gene expression in the human and mouse kidney, liver, lung, heart, muscle, and adipose tissue. Applying our novel comparative microarray approach, we confirmed 10 kidney, 11 liver, 11 lung, 11 heart, 8 muscle, and 8 adipose specific genes. The accuracy of this approach was further verified by employing semi-quantitative PCR reaction and by searching for gene function information in existing publications. Three novel tissue-specific genes were discovered by this approach including AMDHD1 (amidohydrolase domain containing 1) in the liver, PRUNE2 (prune homolog 2) in the heart, and ACVR1C (activin A receptor, type IC) in adipose tissue. We further confirmed the tissue-specific expression of these 3 novel genes by real-time PCR. Among them, ACVR1C is adipose tissue-specific and adipocyte-specific in adipose tissue, and can be used as an adipocyte developmental marker. From GEO profiles, we predicted the processes in which AMDHD1 and PRUNE2 may participate. Our approach provides a novel way to identify new sets of tissue-specific genes and to predict functions in which they may be involved. PMID:23741331

Song, Yan; Ahn, Jinsoo; Suh, Yeunsu; Davis, Michael E; Lee, Kichoon

2013-05-31

53

Identification of tumor epithelium and stroma in tissue microarrays using texture analysis  

PubMed Central

Background The aim of the study was to assess whether texture analysis is feasible for automated identification of epithelium and stroma in digitized tumor tissue microarrays (TMAs). Texture analysis based on local binary patterns (LBP) has previously been used successfully in applications such as face recognition and industrial machine vision. TMAs with tissue samples from 643 patients with colorectal cancer were digitized using a whole slide scanner and areas representing epithelium and stroma were annotated in the images. Well-defined images of epithelium (n = 41) and stroma (n = 39) were used for training a support vector machine (SVM) classifier with LBP texture features and a contrast measure C (LBP/C) as input. We optimized the classifier on a validation set (n = 576) and then assessed its performance on an independent test set of images (n = 720). Finally, the performance of the LBP/C classifier was evaluated against classifiers based on Haralick texture features and Gabor filtered images. Results The proposed approach using LPB/C texture features was able to correctly differentiate epithelium from stroma according to texture: the agreement between the classifier and the human observer was 97 per cent (kappa value = 0.934, P < 0.0001) and the accuracy (area under the ROC curve) of the LBP/C classifier was 0.995 (CI95% 0.991-0.998). The accuracy of the corresponding classifiers based on Haralick features and Gabor-filter images were 0.976 and 0.981 respectively. Conclusions The method illustrates the capability of automated segmentation of epithelial and stromal tissue in TMAs based on texture features and an SVM classifier. Applications include tissue specific assessment of gene and protein expression, as well as computerized analysis of the tumor microenvironment. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/4123422336534537

2012-01-01

54

High-resolution immunophenotyping of subcellular compartments in tissue microarrays by enzyme metallography.  

PubMed

Ultrasensitive bright field in situ hybridization assays using enzyme metallography (EnzMet) have been developed and validated, but little is known regarding the applicability of EnzMet for immunophenotypic detection of protein via IHC. Superior resolution via discrete metallographic deposits offers the potential for enhancing high-resolution immunophenotyping. Using high-complexity tissue microarrays (TMAs), 88 common solid tumors were evaluated by automated EnzMet (Nanoprobes and Ventana). Targets were chosen to assess the ability of EnzMet to specifically localize encoded antigens in the nucleus (estrogen receptor), cytoplasm (cytokeratins), and cytoplasmic membrane (HER2) in TMAs. Results were compared with conventional IHC diaminobenzidine (DAB) immunostaining. There was full concordance between the EnzMet and conventional IHC results. Furthermore, the EnzMet reaction products did not appreciably diffuse, were dense and sharply defined, and provided excellent high-resolution differentiation of cellular compartments in paraffin sections for the nuclear, cytoplasmic, and cell membrane-localized antigens evaluated. The higher density of elemental silver deposited during enzyme metallography permitted evaluation of core immunophenotypes at a relatively low magnification, allowing more tissue to be screened in an efficient manner. This preliminary study shows the utility of using enzyme metallography for high-resolution immunophenotyping in TMAs. PMID:16280669

Tubbs, Raymond; Pettay, James; Powell, Richard; Hicks, David G; Roche, Patrick; Powell, William; Grogan, Thomas; Hainfeld, James F

2005-12-01

55

Hyperspectral microscopic analysis of normal, benign and carcinoma microarray tissue sections  

NASA Astrophysics Data System (ADS)

We apply a unique micro-optoelectromechanical tuned light source and new algorithms to the hyper-spectral microscopic analysis of human colon biopsies. The tuned light prototype (Plain Sight Systems Inc.) transmits any combination of light frequencies, range 440nm 700nm, trans-illuminating H and E stained tissue sections of normal (N), benign adenoma (B) and malignant carcinoma (M) colon biopsies, through a Nikon Biophot microscope. Hyper-spectral photomicrographs, randomly collected 400X magnication, are obtained with a CCD camera (Sensovation) from 59 different patient biopsies (20 N, 19 B, 20 M) mounted as a microarray on a single glass slide. The spectra of each pixel are normalized and analyzed to discriminate among tissue features: gland nuclei, gland cytoplasm and lamina propria/lumens. Spectral features permit the automatic extraction of 3298 nuclei with classification as N, B or M. When nuclei are extracted from each of the 59 biopsies the average classification among N, B and M nuclei is 97.1%; classification of the biopsies, based on the average nuclei classification, is 100%. However, when the nuclei are extracted from a subset of biopsies, and the prediction is made on nuclei in the remaining biopsies, there is a marked decrement in performance to 60% across the 3 classes. Similarly the biopsy classification drops to 54%. In spite of these classification differences, which we believe are due to instrument and biopsy normalization issues, hyper-spectral analysis has the potential to achieve diagnostic efficiency needed for objective microscopic diagnosis.

Maggioni, Mauro; Davis, Gustave L.; Warner, Frederick J.; Geshwind, Frank B.; Coppi, Andreas C.; DeVerse, Richard A.; Coifman, Ronald R.

2006-03-01

56

Subcellular localization of p27 and prostate cancer recurrence: automated digital microscopy analysis of tissue microarrays.  

PubMed

Previous investigations have linked decreased nuclear expression of the cell cycle inhibitor p27 with poor outcome in prostate cancer. However, these reports are inconsistent regarding the magnitude of that association and its independence from other predictors. Moreover, cytoplasmic translocation of p27 has been proposed as a negative prognostic sign. Given the cost and accuracy limitations of manual scoring, particularly of tissue microarrays, we determined if laser-based fluorescence microscopy could provide automated analysis of p27 in both nuclear and cytoplasmic locations and, thus, clarify its significance as a prognostic biomarker. We constructed tissue microarrays covering 202 recurrent cases (rising prostate-specific antigen) and 202 matched controls without recurrence. Quadruplicate tumor samples encompassed 5 slides and 1616 cancer histospots. Cases and controls matched on age, Gleason grade, stage, and hospital. We immunolabeled epithelial cytoplasm with Alexafluor 647, p27 with Alexafluor 488, and nuclei with 4c6-diamidino-2-phenylindole·2HCl. Slides were scanned on an iCys laser scanning cytometer (CompuCyte Corp, Cambridge, MA). Nuclear crowding required a stereological approach--random arrays of circles (phantoms) were layered on images and the content of each phantom was analyzed in scatter plots. Both nuclear and cytoplasmic p27 were significantly lower in cases versus controls (P = .014 and P = .004, respectively). Regression models controlling for matching variables plus prostate-specific antigen showed strong linear trends for increased risk of recurrence with lower p27 in both nucleus and cytoplasm (highest versus lowest quartile; odds ratio, 0.35; P = .006). Manual scoring identified an inverse association between p27 expression and tumor grade but no independent association with recurrence. In conclusion, we developed an automated method for subcellular scoring of p27 without the need to segment individual cells. Our method identified a strong relationship, independent of tumor grade, stage, and prostate-specific antigen, between p27 expression--regardless of subcellular location--and prostate cancer recurrence. This relationship was not observed with manual scoring. PMID:21292307

Ananthanarayanan, Viju; Deaton, Ryan J; Amatya, Anup; Macias, Virgilia; Luther, Ed; Kajdacsy-Balla, Andre; Gann, Peter H

2011-02-02

57

Extending the tissue microarray data exchange specification for inclusion of data analysis results  

PubMed Central

Background: The Tissue Microarray Data Exchange Specification (TMA DES) is an eXtensible Markup Language (XML) specification for encoding TMA experiment data in a machine-readable format that is also human readable. TMA DES defines Common Data Elements (CDEs) that form a basic vocabulary for describing TMA data. TMA data are routinely subjected to univariate and multivariate statistical analysis to determine differences or similarities between pathologically distinct groups of tumors for one or more markers or between markers for different groups. Such statistical analysis tests include the t-test, ANOVA, Chi-square, Mann-Whitney U, and Kruskal-Wallis tests. All these generate output that needs to be recorded and stored with TMA data. Materials and Methods: We propose extending the TMA DES to include syntactic and semantic definitions of CDEs for describing the results of statistical analyses performed upon TMA DES data. These CDEs are described in this paper and it is illustrated how they can be added to the TMA DES. We created a Document Type Definition (DTD) file defining the syntax for these CDEs, and a set of ISO 11179 entries providing semantic definitions for them. We describe how we wrote a program in R that read TMA DES data from an XML file, performed statistical analyses on that data, and created a new XML file containing both the original XML data and CDEs representing the results of our analyses. This XML file was submitted to XML parsers in order to confirm that they conformed to the syntax defined in our extended DTD file. TMA DES XML files with deliberately introduced errors were also parsed in order to verify that our new DTD file could perform error checking. Finally, we also validated an existing TMA DES XML file against our DTD file in order to demonstrate the backward compatibility of our DTD. Results: Our experiments demonstrated the encoding of analysis results using our proposed CDEs. We used XML parsers to confirm that these XML data were syntactically correct and conformed to the rules specified in our extended TMA DES DTD. We also demonstrated that this extended DTD was capable of being used to successfully perform error checking, and was backward compatible with pre-existing TMA DES data which did not use our new CDEs. Conclusions: The TMA DES allows Tissue Microarray data to be shared. A variety of statistical tests are used to analyze such data. We have proposed a set of CDEs as an extension to the TMA DES which can be used to annotate TMA DES data with the results of statistical analyses performed on that data. We performed experiments which demonstrated the usage of TMA DES data containing our proposed CDEs.

Lyttleton, Oliver; Wright, Alexander; Treanor, Darren; Quirke, Philip; Lewis, Paul

2011-01-01

58

HER2 in gastric cancer: Comparative analysis of three different antibodies using whole-tissue sections and tissue microarrays  

PubMed Central

AIM: To compare the performance of three commercially available anti-human epidermalgrowth factor receptor 2 (HER2) antibodies in whole-tissue sections and tissue microarrays (TMAs) of a series of gastric tumors. METHODS: We present a comparative analysis of three anti-HER2 antibodies (HercepTest, 4B5 and SP3) using TMA and whole-tissue sections prepared from the same paraffin blocks of 199 gastric adenocarcinomas operated upon between January 2004 and December 2008 at a Brazilian cancer hospital. The data on the patients’ age, sex, the anatomical location of the tumor and the Lauren’s histological classification were collected from clinical and pathological records. The immunohistochemical (IHC) results were examined by two pathologists and the cases were classified as positive (3+), equivocal (2+) and negative (0 or 1+), according to the criteria of the IHC scoring system of gastric cancer. TMAs and whole-tissue sections were evaluated separately and independently. All cases yielding discordant IHC results and/or scored as 2+ were subjected to dual-color in situ hybridization in order to determine the final HER2 status. Besides determining the sensitivity and predictive value for HER2-positive status, we measured the accuracy of each antibody by calculating the area under the receiver operating characteristic (ROC) curve. The agreement between the results obtained using the TMAs and those obtained using the whole-tissue sections was assessed by means of Kappa coefficient. RESULTS: Intratumoral heterogeneity of HER2 expression was observed with all antibodies. HER2-positive expression (3+) in the whole-tissue sections was observed in 23 cases (11.6%) using the 4B5 antibody, in 18 cases (9.1%) using the SP3 antibody and in 10 cases (5.1%) using the HercepTest antibody. In the TMAs, 11 positive cases (5.6%) were identified using SP3 antibody, 9 (4.6%) using the 4B5 antibody and 6 (3%) using the HercepTest antibody. The sensitivity using whole-tissue sections and TMA, respectively, was 95.2% and 42.9% with 4B5, 90.5% and 66.7% with SP3 and 47.6% and 42.9% with HercepTest. The accuracy, calculated from the area under the ROC curve, using whole-tissue sections and TMA, respectively, was 0.91 and 0.79 by 4B5, 0.86 and 0.80 by SP3 and 0.73 and 0.71 by HercepTest. The concordance of the results obtained using whole-tissue sections and TMA was 97.4% (Kappa 0.75) using HercepTest, 85.6% (Kappa 0.56) using SP3 and 84.1% (Kappa 0.38) using 4B5. CONCLUSION: The use of the 4B5 antibody on whole-tissue sections was the most accurate IHC method for evaluating HER2 expression in gastric adenocarcinoma.

Abrahao-Machado, Lucas Faria; Jacome, Alexandre Andrade dos Anjos; Wohnrath, Durval Renato; dos Santos, Jose Sebastiao; Carneseca, Estela Cristina; Fregnani, Jose Humberto Tavares Guerreiro; Scapulatempo-Neto, Cristovam

2013-01-01

59

cDNA microarray analysis of small plant tissue samples using a cDNA tag target amplification protocol.  

PubMed

Microarray technology is becoming an important comprehensive tool to study gene expression in plants. However, the use of this technology is limited by the large amount of sample tissue needed for microarray analysis. Generally, 50-200 microg of total RNA and 1-2 microg of mRNA is required for each hybridisation, which is equivalent to 50-100 mg of plant tissue. This requirement for large amounts of starting material severely constrains the use of microarrays for transcript profiling in specific tissues and cell types during plant development. Here we report on a robust and reliable target amplification method that enables transcript profiling from sub-mg amounts of plant tissue. Using 0.1 microg of total RNA we show that twofold expression differences are possible to distinguish with 99% confidence. We also demonstrate the application of this method in an analysis of secondary phloem development in hybrid aspen using defined tissue sections, corresponding to 2-4 cell layers with a fresh weight of approximately 0.5 mg. PMID:11309148

Hertzberg, M; Sievertzon, M; Aspeborg, H; Nilsson, P; Sandberg, G; Lundeberg, J

2001-03-01

60

Protein profile of the luteal phase endometrium by tissue microarray assessment.  

PubMed

To investigate the luteal phase endometrial expression of leukemia inhibitor factor (LIF), insulin-like growth factor 1 (IGF-1), progesterone receptor (PR), claudin 4 (CLDN4), vascular-endothelial growth factor receptor 3 (VEGFR-3), bone morphogenetic protein 4 (BMP-4) and citokeratin 7 (CK-7), we obtained luteal phase endometrial samples from 52 women. Samples were dated and integrated using a tissue microarray (TMA). Samples were immunostained for LIF, IGF-1, PR, CLDN4, VEGFR-3, BMP-4 and CK-7. Frequencies of positive expressions at the early, mid and late luteal phases were compared by two proportions test. Concomitant expression of these proteins was assessed with Chi-square or Fischer's test. The frequency of LIF was positively correlated to the frequency of IGF-1 (r = 0.99; p < 0.05) and PR (r = 0.99; p < 0.05), and the correlation between IGF-1 and PR tended to be significant (r = 0.98; p < 0.1). The expression of PR was associated with the absence of CLDN4 (p < 0.001). Thus, expression of LIF, IGF-1 and PR are correlated during the luteal phase, and immunohistochemistry for these proteins might be used to assist in the assessment of endometrial maturation. In addition, the expression of CLDN4 and PR was not concomitant, warranting further investigation on the relationship of their endometrial expression. PMID:19557595

Serafini, Paulo; Da Rocha, André Monteiro; De Toledo Osório, Cyntia Aparecida Bueno; Smith, Gary Daniel; Hassun, Pericles Assad; da Silva, Ismael Guerreiro Dale Cotrim Guerreiro; Da Motta, Eduardo Leme Alves; Baracat, Edmund Chada

2009-09-01

61

Phenotypic characterization of hereditary epithelial ovarian cancer based on a tissue microarray study.  

PubMed

The pathologic and immunohistochemical features of familial epithelial ovarian cancers are not well understood. We have carried out a comprehensive immunohistochemical study of familial ovarian carcinomas from women with and without BRCA1 or BRCA2 mutations, in order to identify specific and/or common features among these different familial case groups (BRCA1, BRCA2 and non-BRCA1/2) and to identify markers of diagnostic value that might help to select more specific treatments. 73 familial primary ovarian carcinomas were analyzed for the expression of 40 antibodies involved in different genetic pathways using a tissue microarray. Serous carcinomas comprised the majority of all three familial case groups. On the other hand, BRCA1 and BRCA2 carcinomas have similar histopathologic features; i.e. they are often high-grade and are usually diagnosed at a more advanced FIGO stage than non-BRCA1/2 carcinomas. In our series, BRCA1 carcinomas had better clinical evolution and they also more frequently over-expressed PR and P53 than BRCA2 and non-BRCA1/2 carcinomas. Unsupervised cluster analysis and survival analysis identified ERCC1 as a potential marker of better clinical outcome for hereditary epithelial ovarian cancer. PMID:23233066

Muñoz-Repeto, I; García, M J; Kamieniak, M; Ramón Y Cajal, T; Domingo, S; Cazorla, A; García Donas, J; Hernando Polo, S; García Sagredo, J M; Hernández, E; Lacambra, C; Saez, R; Robles, L; Borrego, S; Prat, J; Palacios, J; Benítez, J

2013-01-01

62

A comparison between manual and automated evaluations of tissue microarray patterns of protein expression.  

PubMed

Tissue microarray technology enables us to evaluate the pattern of protein expression in large numbers of samples. However, manual data acquisition and analysis still represent a challenge because they are subjective and time-consuming. Automated analysis may thus increase the speed and reproducibility of evaluation. However, the reliability of automated analysis systems should be independently evaluated. Herein, the expression of phosphorylated AKT and mTOR was determined by ScanScope XT (Aperio; Vista, CA) and ACIS III (Dako; Glostrup, Denmark) and compared with the manual analysis by two observers. The percentage of labeled pixels or nuclei analysis had a good correlation between human observers and automated systems (? = 0.855 and 0.879 for ScanScope vs. observers and ? = 0.765 and 0.793 for ACIS III vs. observers). The intensity of labeling determined by ScanScope was also correlated with that found by the human observers (correlation index of 0.946 and 0.851 for pAKT and 0.851 and 0.875 for pmTOR). However, the correlation between ACIS III and human observation varied for labeling intensity and was considered poor in some cases (correlation index of 0.718 and 0.680 for pAKT and 0.223 and 0.225 for pmTOR). Thus, the percentage of positive pixels or nuclei determination was satisfactorily performed by both systems; however, labeling intensity was better identified by ScanScope XT. PMID:23340270

Alvarenga, Arthur W; Coutinho-Camillo, Claudia M; Rodrigues, Bruna R; Rocha, Rafael M; Torres, Luiz Fernando B; Martins, Vilma R; da Cunha, Isabela W; Hajj, Glaucia N M

2013-01-21

63

Glypican-3 as a potential differential diagnosis marker for hepatocellular carcinoma: a tissue microarray-based study.  

PubMed

The differential diagnosis between hepatocellular carcinoma (HCC) and benign hepatic lesions is still difficult and new biochemical markers for HCC are required. The aim of this study was to assess the differential diagnostic value of glypican-3 (GPC3) immunostaining in HCC patients. 147 cases of surgically excised HCC tissues, 94 cases from needle biopsies, and tissue microarrays were used for this study. The tissue microarrays contained 449 specimens including: 115 HCC, 25 intrahepatic cholangiocellular carcinoma, 29 lung adenocarcinoma, 23 squamous cell lung carcinoma, 53 ovary adenocarcinoma, 44 renal cell carcinoma, 30 prostate acinar adenocarcinoma, 42 breast carcinoma, 41 gastric carcinoma and 47 colorectal carcinoma. The immunolocalization of GPC3 was measured using immunohistochemical staining. Among 147 surgically excised HCC samples, 87.1% (128/147) were GPC3 positive. No GPC3 expression, however, was observed in paracarcinomatous and cirrhotic tissues. In needle biopsy tissues, GPC3 was positively expressed in 81.9% (77/94). Among tissue microassays, HCCs showed positive GPC3 expression in 55.7% (64/115), while 9.6% (5/52) of lung carcinoma and 5.7% (3/53) of ovary adenocarcinoma also were positively stained. The other tumor types showed negative GPC3 expression. In conclusion, our results show that GPC3 is specifically overexpressed in HCC tissue and may be regarded as a potential marker for differential diagnostic hepatocellular carcinoma. PMID:22119409

Zhang, Lijie; Liu, Hui; Sun, Lin; Li, Ning; Ding, Huiguo; Zheng, Jie

2011-11-26

64

Subcellular Localization of p27 and Prostate Cancer Recurrence: Automated Digital Microscopy Analysis of Tissue Microarrays  

PubMed Central

Previous investigations have linked decreased nuclear expression of the cell cycle inhibitor p27 with poor outcome in prostate cancer. However, these reports are inconsistent regarding the magnitude of that association and its independence from other predictors. Moreover, cytoplasmic translocation of p27 has been proposed as a negative prognostic sign. Given the cost and accuracy limitations of manual scoring, particularly of tissue microarrays (TMAs), we determined if laser-based fluorescence microscopy could provide automated analysis of p27 in both nuclear and cytoplasmic locations, and thus clarify its significance as a prognostic biomarker. We constructed TMAs covering 202 recurrent cases (rising PSA) and 202 matched controls without recurrence. Quadruplicate tumor samples encompassed 5 slides and 1,616 cancer histospots. Cases and controls matched on age, Gleason grade, stage and hospital. We immunolabeled epithelial cytoplasm with Alexa647®; p27 with Alexa488®; and nuclei with DAPI. Slides were scanned on an iCys® laser scanning cytometer. Nuclear crowding required a stereological approach - random arrays of circles (phantoms) were layered on images and the content of each phantom analyzed in scatterplots. Both nuclear and cytoplasmic p27 were significantly lower in cases vs. controls (P=0.014, P=0.004, respectively). Regression models controlling for matching variables plus PSA showed strong linear trends for increased risk of recurrence with lower p27 in both nucleus and cytoplasm (highest vs lowest quartile, OR=0.35, P=0.006). Manual scoring identified an inverse association between p27 expression and tumor grade, but no independent association with recurrence. In conclusion, we developed an automated method for subcellular scoring of p27 without the need to segment individual cells. Our method identified a strong relationship, independent of tumor grade, stage and PSA, between p27 expression – regardless of subcellular location - and prostate cancer recurrence. This relationship was not observed with manual scoring.

Ananthanarayanan, Viju; Deaton, Ryan J.; Amatya, Anup; Macias, Virgilia; Luther, Ed; Kajdacsy-Balla, Andre; Gann, Peter H.

2010-01-01

65

Lymphatic Tissue Engineering Progress and Prospects  

PubMed Central

In the last 5 years major advances have been made in the field of tissue engineering. However, while engineering of tissues from nearly every major system in the body have been studied and improved, little has been done with the engineering of viable lymphatic tissues. Recent advances in understanding of lymphatic biology have allowed the easy isolation of pure lymphatic cell cultures, increasing, in turn, the ability to study lymphatic biology in greater detail. This has allowed the elucidation of lymphatic properties on the structural, cellular, and molecular levels, making possible the successful development of the first lymphatic engineered tissues. Among such advances are the engineering of lymphatic capillaries, the development of a functioning bioreactor designed to culture lymph nodes in vitro, and in vivo growth of lymphatic organoids. However, there has been no research on the engineering of functional lymphangions. While the advances made in the study of lymphatic biology are encouraging, the complexities of the system make the engineering of certain functional lymphatic tissues somewhat more difficult.

Hitchcock, Thomas; Niklason, Laura

2008-01-01

66

A novel microarray approach reveals new tissue-specific signatures of known and predicted mammalian microRNAs  

PubMed Central

Microarrays to examine the global expression levels of microRNAs (miRNAs) in a systematic in-parallel manner have become important tools to help unravel the functions of miRNAs and to understand their roles in RNA-based regulation and their implications in human diseases. We have established a novel miRNA-specific microarray platform that enables the simultaneous expression analysis of both known and predicted miRNAs obtained from human or mouse origin. Chemically modified 2?-O-(2-methoxyethyl)-(MOE) oligoribonucleotide probes were arrayed onto Evanescent Resonance (ER) microchips by robotic spotting. Supplementing the complementary probes against miRNAs with carefully designed mismatch controls allowed for accurate sequence-specific determination of miRNA expression profiles obtained from a panel of mouse tissues. This revealed new expression signatures of known miRNAs as well as of novel miRNAs previously predicted using bioinformatic methods. Systematic confirmation of the array data with northern blotting and, in particular, real-time PCR suggests that the described microarray platform is a powerful tool to analyze miRNA expression patterns with rapid throughput and high fidelity.

Beuvink, Iwan; Kolb, Fabrice A.; Budach, Wolfgang; Garnier, Arlette; Lange, Joerg; Natt, Francois; Dengler, Uwe; Hall, Jonathan; Weiler, Jan

2007-01-01

67

Progress in the use of microarray technology to study the neurobiology of disease  

Microsoft Academic Search

The diverse functions of the brain are mediated by neurons and glia whose phenotype is defined by a dynamically maintained set of gene transcripts, or 'transcriptome'. Large-scale analysis of gene expression in postmortem brain using microarray technology has the potential to elucidate molecular changes that occur in disease states. There are unique challenges associated with studies of postmortem brain, including

Károly Mirnics; Jonathan Pevsner

2004-01-01

68

A Novel Survival-Based Tissue Microarray of Pancreatic Cancer Validates MUC1 and Mesothelin as Biomarkers  

PubMed Central

Background One–fifth of patients with seemingly ‘curable’ pancreatic ductal adenocarcinoma (PDA) experience an early recurrence and death, receiving no definable benefit from a major operation. Some patients with advanced stage tumors are deemed ‘unresectable’ by conventional staging criteria (e.g. liver metastasis), yet progress slowly. Effective biomarkers that stratify PDA based on biologic behavior are needed. To help researchers sort through the maze of biomarker data, a compendium of ?2500 published candidate biomarkers in PDA was compiled (PLoS Med, 2009. 6(4) p. e1000046). Methods and Findings Building on this compendium, we constructed a survival tissue microarray (termed s-TMA) comprised of short-term (cancer-specific death <12 months, n?=?58) and long-term survivors (>30 months, n?=?79) who underwent resection for PDA (total, n?=?137). The s-TMA functions as a biological filter to identify bona fide prognostic markers associated with survival group extremes (at least 18 months separate survival groups). Based on a stringent selection process, 13 putative PDA biomarkers were identified from the public biomarker repository. Candidates were tested against the s-TMA by immunohistochemistry to identify the best markers of tumor biology. In a multivariate model, MUC1 (odds ratio, OR?=?28.95, 3+ vs. negative expression, p?=?0.004) and MSLN (OR?=?12.47, 3+ vs. negative expression, p?=?0.01) were highly predictive of early cancer-specific death. By comparison, pathologic factors (size, lymph node metastases, resection margin status, and grade) had ORs below three, and none reached statistical significance. ROC curves were used to compare the four pathologic prognostic features (ROC area?=?0.70) to three univariate molecular predictors (MUC1, MSLN, MUC2) of survival group (ROC area?=?0.80, p?=?0.07). Conclusions MUC1 and MSLN were superior to pathologic features and other putative biomarkers as predicting survival group. Molecular assays comparing cancers from short and long survivors are an effective strategy to screen biomarkers and prioritize candidate cancer genes for diagnostic and therapeutic studies.

Winter, Jordan M.; Tang, Laura H.; Klimstra, David S.; Brennan, Murray F.; Brody, Jonathan R.; Rocha, Flavio G.; Jia, Xiaoyu; Qin, Li-Xuan; D'Angelica, Michael I.; DeMatteo, Ronald P.; Fong, Yuman; Jarnagin, William R.; O'Reilly, Eileen M.; Allen, Peter J.

2012-01-01

69

Reverse phase protein microarrays which capture disease progression show activation of pro-survival pathways at the cancer invasion front  

Microsoft Academic Search

Protein arrays are described for screening of molecular markers and pathway targets in patient matched human tissue during disease progression. In contrast to previous protein arrays that immobilize the probe, our reverse phase protein array immobilizes the whole repertoire of patient proteins that represent the state of individual tissue cell populations undergoing disease transitions. A high degree of sensitivity, precision

Cloud P Paweletz; Lu Charboneau; Verena E Bichsel; Nicole L Simone; Tina Chen; John W Gillespie; Michael R Emmert-Buck; Mark J Roth; Emanuel F Petricoin III; Lance A Liotta

2001-01-01

70

Microarray analysis of CA1 pyramidal neurons in a mouse model of tauopathy reveals progressive synaptic dysfunction  

PubMed Central

The hTau mouse model of tauopathy was utilized to assess gene expression changes in vulnerable hippocampal CA1 neurons. CA1 pyramidal neurons were microaspirated via laser capture microdissection followed by RNA amplification in combination with custom-designed microarray analysis and qPCR validation in hTau mice and nontransgenic (ntg) littermates aged 11-14 months. Statistical analysis revealed ?8% of all the genes on the array platform were dysregulated, with notable downregulation of several synaptic-related markers including synaptophysin (Syp), synaptojanin, and synaptobrevin, among others. Downregulation was also observed for select glutamate receptors (GluRs), Psd-95, TrkB, and several protein phosphatase subunits. In contrast, upregulation of tau isoforms and a calpain subunit were found. Microarray assessment of synaptic-related markers in a separate cohort of hTau mice at 7-8 months of age indicated only a few alterations compared to the 11-14 month cohort, suggesting progressive synaptic dysfunction occurs as tau accumulates in CA1 pyramidal neurons. An assessment of SYP and PSD-95 expression was performed in the hippocampal CA1 sector of hTau and ntg mice via confocal laser scanning microscopy along with hippocampal immunoblot analysis for protein-based validation of selected microarray observations. Results indicate significant decreases in SYP-immunoreactive and PSD-95-immunoreactive puncta as well as downregulation of SYP-immunoreactive and PSD-95-immunoreactive band intensity in hTau mice compared to age-matched ntg littermates. In summary, the high prevalence of downregulation of synaptic-related genes indicates that the moderately aged hTau mouse may be a model of tau-induced synaptodegeneration, and has profound effects on how we perceive progressive tau pathology affecting synaptic transmission in AD.

Alldred, Melissa J.; Duff, Karen E.; Ginsberg, Stephen D.

2011-01-01

71

Extraction and labeling methods for microarrays using small amounts of plant tissue.  

PubMed

Procedures were developed to maximize the yield of high-quality RNA from small amounts of plant biomass for microarrays. Two disruption techniques (bead milling and pestle and mortar) were compared for the yield and the quality of RNA extracted from 1-week-old Arabidopsis thaliana seedlings (approximately 0.5-30 mg total biomass). The pestle and mortar method of extraction showed enhanced RNA quality at the smaller biomass samples compared with the bead milling technique, although the quality in the bead milling could be improved with additional cooling steps. The RNA extracted from the pestle and mortar technique was further tested to determine if the small quantity of RNA (500 ng-7 microg) was appropriate for microarray analyses. A new method of low-quantity RNA labeling for microarrays (NuGEN Technologies, Inc.) was used on five 7-day-old seedlings (approximately 2.5 mg fresh weight total) of Arabidopsis that were grown in the dark and exposed to 1 h of red light or continued dark. Microarray analyses were performed on a small plant sample (five seedlings; approximately 2.5 mg) using these methods and compared with extractions performed with larger biomass samples (approximately 500 roots). Many well-known light-regulated genes between the small plant samples and the larger biomass samples overlapped in expression changes, and the relative expression levels of selected genes were confirmed with quantitative real-time polymerase chain reaction, suggesting that these methods can be used for plant experiments where the biomass is extremely limited (i.e. spaceflight studies). PMID:19140889

Stimpson, Alexander J; Pereira, Rhea S; Kiss, John Z; Correll, Melanie J

2009-01-07

72

Tissue Microarray-Based Evaluation of Chromatin Assembly Factor-1 (CAF-1)/p60 as Tumour Prognostic Marker.  

PubMed

In this study we aimed to confirm the emerging role of Chromatin Assembly Factor 1 (CAF-1 p60) as a new proliferation and prognostic marker for cancer and to test the usefulness of the tissue microarray technique (TMA) for CAF-1 p60 rapid screening in several human malignancies. CAF-1 is a histone chaperone, regulating chromatin dynamics during DNA replication and repair in eukaryotics. TMA is a powerful high-throughput methodology in the study of cancer, allowing simultaneous assessment of different biomarkers within large numbers of tissue specimens. We generated TMA taking 3 mm diameter-core biopsies from oral squamous cell carcinoma, prostate cancer, salivary gland tumours and skin melanoma specimens, which had been previously tested for CAF-1 p60 on routine tissue sections. We also analysed, for the first time, 30 larynx and 30 skin squamous cell carcinomas. CAF-1 p60 resulted over-expressed in both the tissue sections and the TMA specimens, with the highest levels of expression in tumours which were more aggressive and metastasizing. Notably, a high degree of agreement was found between the CAF-1 p60 assessment on TMAs and on routine tissue sections. Our findings confirm the prognostic role of CAF-1 p60 and indicate TMA as a really advantageous method for CAF-1 p60 immunohistochemical screening, allowing savings on both tissue quantity and operator-time. PMID:23109837

Mascolo, Massimo; Ilardi, Gennaro; Merolla, Francesco; Russo, Daniela; Vecchione, Maria Luisa; de Rosa, Gaetano; Staibano, Stefania

2012-09-05

73

Identification of tissue-specific genes in nasopharyngeal epithelial tissue and differentially expressed genes in nasopharyngeal carcinoma by suppression subtractive hybridization and cDNA microarray.  

PubMed

Suppression subtractive hybridization (SSH) was performed for isolation of tissue-specific genes in nasopharyngeal epithelial tissue, by use of cDNAs from human adult nasopharyngeal epithelial tissue as tester and mixed cDNAs from esophagus, lung, liver, heart, stomach, spleen, skeletal muscle, kidney, and skin as drivers. Fourteen differentially expressed genes in nasopharyngeal epithelial tissue were obtained. Among these genes, LPLUNC1 and SPLUNC1 were confirmed to be specifically expressed in nasopharyngeal epithelial tissue and the trachea. A novel transcript of SPLUNC1, which we designate NASG, was found. We also combined SSH and cDNA microarray hybridization to identify genes whose expressions were altered in nasopharyngeal carcinoma (NPC). We used NPC cell line HNE1 and primary human embryo nasopharyngeal epithelial cells in one SSH experiment, and NPC biopsies and normal adult nasopharyngeal epithelial tissue in another. Some 1,200 SSH inserts from four subtractive cDNA libraries were arrayed onto nylon membranes by use of robotic printing. Differential gene expression was verified by hybridizing of the membranes with radioactively labeled first-strand cDNA from NPC cell line HNE1, primary human embryo nasopharyngeal epithelial cells, NPC biopsies, and normal adult nasopharyngeal epithelial tissue. Seventeen differentially expressed genes in NPC were obtained. Among these genes, we identified SPLUNC1 and LPLUNC1 to be down-expressed in NPC biopsies (34/48, 33/48). PMID:12874788

Zhang, Bicheng; Nie, Xinmin; Xiao, Bingyi; Xiang, Juanjuan; Shen, Shourong; Gong, Jialei; Zhou, Ming; Zhu, Shiguo; Zhou, Jie; Qian, Jun; Lu, Hongbin; He, Xianfeng; Li, Xiaoling; Hu, Gengxi; Li, Guiyuan

2003-09-01

74

Selective evolutionary pressure from the tissue microenvironment drives tumor progression  

Microsoft Academic Search

Cells grow within defined environmental niches and are subject to microenvironmental control. Outside of their niche, the environment is hostile, the normal cells lack appropriate survival signals which leads to anoikis. During tumor development and progression, malignant cells must escape the local tissue control and resist anoikis. The inherent genetic instability of tumor cells makes their phenotype very plastic, which

Keiran S. M. Smalley; Patricia A. Brafford; Meenhard Herlyn

2005-01-01

75

Unconventional microarray design reveals the response to obesity is largely tissue specific: analysis of common and divergent responses to diet-induced obesity in insulin-sensitive tissues.  

PubMed

Obesity is a chronic condition involving the excessive accumulation of adipose tissue that adversely affects all systems in the body. The aim of the present study was to employ an unbiased, genome-wide assessment of transcript abundance in order to identify common gene expression pathways within insulin-sensitive tissues in response to dietary-induced diabetes. Following 20 weeks of chow or high-fat feeding (60% kcal), age-matched mice underwent a euglycemic-hyperinsulinemic clamp to assess insulin sensitivity. High-fat-fed animals were obese and highly insulin resistant, disposing of ?75% less glucose compared with their chow-fed counterparts. Tissues were collected, and gene expression was examined by microarray in 4 tissues known to exhibit obesity-related metabolic disturbances: white adipose tissue, skeletal muscle, liver, and heart. A total of 463 genes were differentially expressed between diets. Analysis of individual tissues showed skeletal muscle to exhibit the largest number of differentially expressed genes (191) in response to high-fat feeding, followed by adipose tissue (169), liver (115), and heart (65). Analyses revealed that the response of individual genes to obesity is distinct and largely tissue specific, with less than 10% of transcripts being shared among tissues. Although transcripts are largely tissue specific, a systems approach shows numerous commonly activated pathways, including those involved in signal transduction, inflammation, oxidative stress, substrate transport, and metabolism. This suggests a coordinated attempt by tissues to limit metabolic perturbations occurring in early-stage obesity. Many identified genes were associated with a variety of disorders, thereby serving as potential links between obesity and its related health risks. PMID:22452611

Lee, Robyn K; Hittel, Dustin S; Nyamandi, Vongai Z; Kang, Li; Soh, Jung; Sensen, Christoph W; Shearer, Jane

2012-03-27

76

A Texture Based Pattern Recognition Approach to Distinguish Melanoma from Non-Melanoma Cells in Histopathological Tissue Microarray Sections  

PubMed Central

Aims Immunohistochemistry is a routine practice in clinical cancer diagnostics and also an established technology for tissue-based research regarding biomarker discovery efforts. Tedious manual assessment of immunohistochemically stained tissue needs to be fully automated to take full advantage of the potential for high throughput analyses enabled by tissue microarrays and digital pathology. Such automated tools also need to be reproducible for different experimental conditions and biomarker targets. In this study we present a novel supervised melanoma specific pattern recognition approach that is fully automated and quantitative. Methods and Results Melanoma samples were immunostained for the melanocyte specific target, Melan-A. Images representing immunostained melanoma tissue were then digitally processed to segment regions of interest, highlighting Melan-A positive and negative areas. Color deconvolution was applied to each region of interest to separate the channel containing the immunohistochemistry signal from the hematoxylin counterstaining channel. A support vector machine melanoma classification model was learned from a discovery melanoma patient cohort (n?=?264) and subsequently validated on an independent cohort of melanoma patient tissue sample images (n?=?157). Conclusion Here we propose a novel method that takes advantage of utilizing an immuhistochemical marker highlighting melanocytes to fully automate the learning of a general melanoma cell classification model. The presented method can be applied on any protein of interest and thus provides a tool for quantification of immunohistochemistry-based protein expression in melanoma.

Rexhepaj, Elton; Agnarsdottir, Margret; Bergman, Julia; Edqvist, Per-Henrik; Bergqvist, Michael; Uhlen, Mathias; Gallagher, William M.; Lundberg, Emma; Ponten, Fredrik

2013-01-01

77

Subjective differences in outcome are seen as a function of the immunohistochemical method used on a colorectal cancer tissue microarray.  

PubMed

Immunohistochemistry is a useful technique to localize antigens in cell preparations and tissue sections and can be helpful in identifying molecular markers that may be predictive of patient outcomes. Subjective assessment of expression and semiquantitative grading systems are the current standards in pathology literature for the analysis of tissue sections. However, expression levels assessed in this manner may be dramatically affected by the method of visualization. Tissue microarray (TMA) is a recently developed technique for the simultaneous high-throughput evaluation of protein expression on tissue samples from large cohorts of patients. The scoring of TMAs has, in general, mirrored the systems utilized for tissue sections. Here, 4 detection systems (avidin-biotin complex, indirect immunofluorescence, peroxidase-labeled polymer conjugate, and the latter with Cyanine-3-Tyramide amplification) were compared using a beta-catenin antibody on a TMA containing a cohort of colorectal cancer specimens. Peroxidase-labeled polymer with or without tyramide enhancement was found to be the most sensitive method, revealing a greater staining intensity and percentage of nuclear staining, without an apparent increase in background. Subjective assessment of expression is highly dependent on the method of visualization and may illustrate why discrepant data is often seen in literature based on immunohistochemistry. PMID:12450422

Chung, Gina G; Kielhorn, Eric P; Rimm, David L

2002-02-01

78

Effects of Long-Term Storage on the Detection of Proteins, DNA, and mRNA in Tissue Microarray Slides  

PubMed Central

Storage of tissue slides has been claimed to induce dramatically reduced antigen detection particularly for immunohistochemistry (IHC). With tissue microarrays, the necessity to serially cut blocks in order to obtain as much material as possible is obvious. The presumed adverse effect of storage might hamper such an approach. The authors designed an experimental setting consisting of four different storage conditions with storage time of tissue slides of up to 1 year. Detection of proteins, DNA, and mRNA was performed using IHC and in situ hybridization techniques. Slight but significant changes in IHC occurred over time. The most important factor is the primary antibody used: four showed no significant changes, whereas limited decreases in 8 antibodies could be detected by image analysis. Whether the antigen was nuclear or cytoplasmic/membranous did not matter. No major differences between different storage conditions could be shown, but storage at 4C was overall the best procedure. Furthermore, gene copy number aberrations, chromosomal translocations, and the presence of mRNA could be detected on slides stored up to 1 year. In conclusion, in tissues optimally formalin fixed and using modern histological techniques, only minute changes in tissue antigenicity are induced by long-term storage.

Karlsson, Mats G.

2011-01-01

79

Microarray gene expression profiling of neural tissues in bovine spastic paresis  

PubMed Central

Background Bovine Spastic Paresis (BSP) is a neuromuscular disorder which affects both male and female cattle. BSP is characterized by spastic contraction and overextension of the gastrocnemious muscle of one or both limbs and is associated with a scarce increase in body weight. This disease seems to be caused by an autosomal and recessive gene, with incomplete penetration, although no genes clearly involved with its onset have been so far identified. We employed cDNA microarrays to identify metabolic pathways affected by BSP in Romagnola cattle breed. Investigation of those pathways at the genome level can help to understand this disease. Results Microarray analysis of control and affected individuals resulted in 268 differentially expressed genes. These genes were subjected to KEGG pathway functional clustering analysis, revealing that they are predominantly involved in Cell Communication, Signalling Molecules and Interaction and Signal Transduction, Diseases and Nervous System classes. Significantly enriched KEGG pathway’s classes for the differentially expressed genes were calculated; interestingly, all those significantly under-expressed in the affected samples are included in Neurodegenerative Diseases. To identify genome locations possibly harbouring gene(s) involved in the disease, the chromosome distribution of the differentially expressed genes was also investigated. Conclusions The cDNA microarray we used in this study contains a brain library and, even if carrying an incomplete transcriptome representation, it has proven to be a valuable tool allowing us to add useful and new information to a poorly studied disease. By using this tool, we examined nearly 15000 transcripts and analysed gene pathways affected by the disease. Particularly, our data suggest also a defective glycinergic synaptic transmission in the development of the disease and an alteration of calcium signalling proteins. We provide data to acquire knowledge of a genetic disease for which literature still presents poor results and that could be further and specifically analysed in the next future. Moreover this study, performed in livestock, may also harbour molecular information useful for understanding human diseases.

2013-01-01

80

Microarray gene expression profiles from mature gonad tissues of Atlantic bluefin tuna, Thunnus thynnus in the Gulf of Mexico  

PubMed Central

Background Bluefin tunas are highly prized pelagic fish species representing a significant economic resource to fisheries throughout the world. Atlantic bluefin tuna (Thunnus thynnus) populations have significantly declined due to overexploitation. As a consequence of their value and population decline, T. thynnus has been the focus of considerable research effort concerning many aspects of their life history. However, in-depth understanding of T. thynnus reproductive biology is still lacking. Knowledge of reproductive physiology is a very important tool for determining effective fisheries and aquaculture management. Transcriptome techniques are proving powerful and provide novel insights into physiological processes. Construction of a microarray from T. thynnus ESTs sourced from reproductive tissues has provided an ideal platform to study the reproductive physiology of bluefin tunas. The aim of this investigation was to compare transcription profiles from the ovaries and testes of mature T. thynnus to establish sex specific variations underlying their reproductive physiology. Results Male and females T. thynnus gonad tissues were collected from the wild and histologically staged. Sub-samples of sexually mature tissues were also measured for their mRNA differential expression among the sexes using the custom microarray design BFT 4X44K. A total of 7068 ESTs were assessed for differential expression of which 1273 ESTs were significantly different (p<0.05) with >2 fold change in expression according to sex. Differential expression for 13 of these ESTs was validated with quantitative PCR. These include genes involved in egg envelope formation, hydration, and lipid transport/accumulation more highly expressed in ovaries compared with testis, while genes involved in meiosis, sperm motility and lipid metabolism were more highly expressed in testis compared with ovaries. Conclusions This investigation has furthered our knowledge of bluefin tunas reproductive biology by using a contemporary transcriptome approach. Gene expression profiles in T. thynnus sexually mature testes and ovaries were characterized with reference to gametogenesis and potential alternative functions. This report is the first application of microarray technology for bluefin tunas and demonstrates the efficacy by which this technique may be used for further characterization of specific biological aspects for this valuable teleost fish.

2012-01-01

81

Comparison of the diagnostic performance of human whole genome microarrays using mixed-tissue RNA reference samples  

Microsoft Academic Search

Universal approaches for assessing the diagnostic performance of microarray assays are essential for the application of microarray technology to clinical and regulatory settings. Reference systems for diagnostic assays in laboratory medicine typically involve the utilization of reference samples, metrics, and reference datasets to ensure that measurements are comparable and true. For microarray performance evaluation and process improvement, reference samples can

Karol L. Thompson; P. Scott Pine

2009-01-01

82

Association of adipocyte genes with ASP expression: a microarray analysis of subcutaneous and omental adipose tissue in morbidly obese subjects  

PubMed Central

Background Prevalence of obesity is increasing to pandemic proportions. However, obese subjects differ in insulin resistance, adipokine production and co-morbidities. Based on fasting plasma analysis, obese subjects were grouped as Low Acylation Stimulating protein (ASP) and Triglyceride (TG) (LAT) vs High ASP and TG (HAT). Subcutaneous (SC) and omental (OM) adipose tissues (n = 21) were analysed by microarray, and biologic pathways in lipid metabolism and inflammation were specifically examined. Methods LAT and HAT groups were matched in age, obesity, insulin, and glucose, and had similar expression of insulin-related genes (InsR, IRS-1). ASP related genes tended to be increased in the HAT group and were correlated (factor B, adipsin, complement C3, p < 0.01 each). Differences between LAT and HAT group were almost exclusively in SC tissue, with little difference in OM tissue. Increased C5L2 (p < 0.01), an ASP receptor, in HAT suggests a compensatory ASP pathway, associated with increased TG storage. Results HAT adipose tissue demonstrated increased lipid related genes for storage (CD36, DGAT1, DGAT2, SCD1, FASN, and LPL), lipolysis (HSL, CES1, perilipin), fatty acid binding proteins (FABP1, FABP3) and adipocyte differentiation markers (CEBP?, CEBP?, PPAR?). By contrast, oxidation related genes were decreased (AMPK, UCP1, CPT1, FABP7). HAT subjects had increased anti-inflammatory genes TGFB1, TIMP1, TIMP3, and TIMP4 while proinflammatory PIG7 and MMP2 were also significantly increased; all genes, p < 0.025. Conclusion Taken together, the profile of C5L2 receptor, ASP gene expression and metabolic factors in adipose tissue from morbidly obese HAT subjects suggests a compensatory response associated with the increased plasma ASP and TG.

2010-01-01

83

Low podoplanin expression of tumor cells predicts poor prognosis in pathological stage IB squamous cell carcinoma of the lung, tissue microarray analysis of 136 patients using 24 antibodies  

Microsoft Academic Search

The aim of this study was to identify clinicopathological and biological prognostic markers for patients who had undergone complete resection of pathological stage IB squamous cell carcinoma (SqCC) of the lung. A total of 136 consecutive stage IB SqCC patients fulfilled eligibility criteria, and their clinicopathological factors were evaluated. Tissue microarrays were also constracted, and immunohistochemical staining with 24 antibodies

Takeo Ito; Genichiro Ishii; Kanji Nagai; Tatsuya Nagano; Masakazu Kojika; Yukinori Murata; Naho Atsumi; Yutaka Nishiwaki; Eishi Miyazaki; Toshihide Kumamoto; Atsushi Ochiai

2009-01-01

84

Hodgkin and Reed-Sternberg cells harbor alterations in the major tumor suppressor pathways and cell-cycle checkpoints: analyses using tissue microarrays  

Microsoft Academic Search

Tumoral cells in Hodgkin lymphoma (HL) display an increased growth fraction and diminished apoptosis, implying a pro- found disturbance of the cell cycle and apoptosis regulation. However, limita- tions of molecular techniques have pre- vented the analysis of the tumor suppres- sor pathways and cell-cycle checkpoints. Tissue microarray (TMA) is a powerful tool for analyzing a large number of mo-

Juan F. Garcia; Francisca I. Camacho; Manuel Morente; Maximo Fraga; Carlos Montalban; Tomas Álvaro; Carmen Bellas; Angel Castano; Ana Diez; Teresa Flores; Carmen Martin; Miguel A. Martinez; Francisco Mazorra; Javier Menarguez; Maria J. Mestre; Manuela Mollejo

2002-01-01

85

Identification of Genes Associated With Progression and Metastasis of Advanced Cervical Cancers After Radiotherapy by cDNA Microarray Analysis  

SciTech Connect

Purpose: To identify a set of genes related to the progression and metastasis of advanced cervical cancer after radiotherapy and to establish a predictive method. Methods and Materials: A total of 28 patients with cervical cancer (15 stage IIIB, 13 stage IVA patients) who underwent definitive radiotherapy between May 1995 and April 2001 were included in this study. All patients were positive for human papillomavirus infection and harbored the wild-type p53 gene. The expression profiles of 14 tumors with local failure and multiple distant metastasis and 14 tumors without metastasis (cancer free) obtained by punch biopsy were compared before treatment, using a cDNA microarray consisting of 23,040 human genes. Results: Sixty-three genes were selected on the basis of a clustering analysis, and the validity of these genes was confirmed using a cross-validation test. The most accurate prediction was achieved for 63 genes (sensitivity, 78.8%; specificity, 38.1%). Some of these genes were already known to be associated with metastasis via chromosomal instability (TTK, BUB1B), extracellular matrix components (matrix metalloproteinase 1 [MMP-1]), and carcinogenesis (protein phosphatase 1 regulatory subunit 7 [PPP1R7]). A 'predictive score' system was developed that could predict the probability for development of metastases using leave-one-out cross-validation methods. Conclusions: The present results may provide valuable information for identified predictive markers and novel therapeutic target molecules for progression and metastasis of advanced cervical cancer.

Harima, Yoko, E-mail: harima@takii.kmu.ac.j [Department of Radiology, Takii Hospital, Kansai Medical University, 10-15 Fumizono-cho, Moriguchi, Osaka 570-8507 (Japan); Ikeda, Koshi; Utsunomiya, Keita; Shiga, Toshiko; Komemushi, Atsushi [Department of Radiology, Takii Hospital, Kansai Medical University, 10-15 Fumizono-cho, Moriguchi, Osaka 570-8507 (Japan); Kojima, Hiroyuki; Nomura, Motoo; Kamata, Minoru; Sawada, Satoshi [Department of Radiology, Hirakata Hospital, Kansai Medical University, 2-3 Shinmachi, Hirakata, Osaka 573-1191 (Japan)

2009-11-15

86

Comparative study of gene expression by cDNA microarray in human colorectal cancer tissues and normal mucosa.  

PubMed

The causative molecular pathways underlying the pathogenesis of colorectal cancer (CRC) need to be better characterized. The purpose of our study was to better understand the genetic mechanism of oncogenesis for human colorectal cancer and to identify new potential tumor markers of use in clinical practice. We used cDNA microarrays to compare gene expression profiles of colorectal biopsies from 25 CRC patients and 13 normal mucosa from adjacent non-cancerous tissues. Findings were validated by real-time PCR; in addition, western blotting and immunochemistry analysis were carried out as further confirmation of differential expression at a protein level. Comparing cancerous tissues with normal colonic mucosa we identified 584 known genes differentially expressed to a significant degree (p<0.001). Many of the transcripts that were more abundant in tumors than in non-neoplastic tissues appear to reflect important events for colon carcinogenesis. For example, a significant number of these genes serve as apoptotic inhibitors (e.g. BFAR, BIRC1, BIRC6). Furthermore, we observed the simultaneous up-regulation of HLA-E and the down-regulation of beta2-microglobulin; these genes strongly support a potential tumor escape strategy from immune surveillance in colon cancer tissues. Our study provides new gene candidates in the pathogenesis of human CRC disease. From our results we hypothesize that CRC cells escape immune surveillance through a specific gene expression alteration; moreover, over-expression of several survival genes seems to confer a more anti-apoptotic phenotype. These genes are involved in pathways not previously implicated in CRC pathogenesis and they may provide new targets for therapy. PMID:16773188

Bianchini, Michele; Levy, Estrella; Zucchini, Cinzia; Pinski, Victor; Macagno, Carlos; De Sanctis, Paola; Valvassori, Luisa; Carinci, Paolo; Mordoh, José

2006-07-01

87

Software Tools for High-Throughput Analysis and Archiving of Immunohistochemistry Staining Data Obtained with Tissue Microarrays  

PubMed Central

The creation of tissue microarrays (TMAs) allows for the rapid immunohistochemical analysis of thousands of tissue samples, with numerous different antibodies per sample. This technical development has created a need for tools to aid in the analysis and archival storage of the large amounts of data generated. We have developed a comprehensive system for high-throughput analysis and storage of TMA immunostaining data, using a combination of commercially available systems and novel software applications developed in our laboratory specifically for this purpose. Staining results are recorded directly into an Excel worksheet and are reformatted by a novel program (TMA-Deconvoluter) into a format suitable for hierarchical clustering analysis or other statistical analysis. Hierarchical clustering analysis is a powerful means of assessing relatedness within groups of tumors, based on their immunostaining with a panel of antibodies. Other analyses, such as generation of survival curves, construction of Cox regression models, or assessment of intra- or interobserver variation, can also be done readily on the reformatted data. Finally, the immunoprofile of a specific case can be rapidly retrieved from the archives and reviewed through the use of Stainfinder, a novel web-based program that creates a direct link between the clustered data and a digital image database. An on-line demonstration of this system is available at http://genome-www.stanford.edu/TMA/explore.shtml.

Liu, Chih Long; Prapong, Wijan; Natkunam, Yasodha; Alizadeh, Ash; Montgomery, Kelli; Gilks, C. Blake; van de Rijn, Matt

2002-01-01

88

Tissue Differential Microarray Analysis of Dexamethasone Induction Reveals Potential Mechanisms of Steroid Glaucoma  

Microsoft Academic Search

PURPOSE. To identify myocilin (TIGR\\/MYOC) properties that are specific to the human trabecular meshwork (HTM). To search for genes highly expressed in dexamethasone (DEX)- induced HTM cells that are barely expressed or absent in DEX-induced cells from other tissues. METHODS. TIGR\\/MYOC induction by DEX (107 M for 8 -10 days) was analyzed by Northern and Western blot analyses in HTM,

Wayne R. Lo; Laura Leigh Rowlette; Montserrat Caballero; Ping Yang; M. Rosario Hernandez; Teresa Borras

2003-01-01

89

High-throughput profiling of tissue and tissue model microarrays: Combined transmitted light and 3-color fluorescence digital pathology.  

PubMed

For many years pathologists have used Hematoxylin and Eosin (H&E), single marker immunohistochemistry (IHC) and in situ hybridization with manual analysis by microscopy or at best simple digital imaging. There is a growing trend to update pathology to a digital workflow to improve objectivity and productivity, as has been done in radiology. There is also a need for tissue-based multivariate biomarker assays to improve the accuracy of diagnostic, prognostic, and predictive testing. Multivariate tests are not compatible with the traditional single marker, manual analysis pathology methods but instead require a digital platform with brightfield and fluorescence imaging, quantitative image analysis, and informatics. Here we describe the use of the Hamamatsu NanoZoomer Digital Pathology slide scanner with HCImage software for combined brightfield and multiplexed fluorescence biomarker analysis and highlight its applications in biomarker research and pathology testing. This combined approach will be an important aid to pathologists in making critical diagnoses. PMID:22200032

Nederlof, Michel; Watanabe, Shigeo; Burnip, Bill; Taylor, D Lansing; Critchley-Thorne, Rebecca

2011-11-15

90

Dysregulated methylation at imprinted genes in prostate tumor tissue detected by methylation microarray  

PubMed Central

Background Imprinting is an important epigenetic regulator of gene expression that is often disrupted in cancer. While loss of imprinting (LOI) has been reported for two genes in prostate cancer (IGF2 and TFPI2), disease-related changes in methylation across all imprinted gene regions has not been investigated. Methods Using an Illumina Infinium Methylation Assay, we analyzed methylation of 396 CpG sites in the promoter regions of 56 genes in a pooled sample of 12 pairs of prostate tumor and adjacent normal tissue. Selected LOI identified from the array was validated using the Sequenom EpiTYPER assay for individual samples and further confirmed by expression data from publicly available datasets. Results Methylation significantly increased in 52 sites and significantly decreased in 17 sites across 28 unique genes (P?tissue using array data from a publicly available database were consistent with the observed LOI patterns, and WT1 hypermethylation was confirmed using quantitative DNA methylation analysis. Conclusions Together, these findings suggest a more widespread dysregulation of genetic imprinting in prostate cancer than previously reported and warrant further investigation.

2013-01-01

91

Assessment of Automated Image Analysis of Breast Cancer Tissue Microarrays for Epidemiologic Studies  

PubMed Central

A major challenge in studies of etiologic heterogeneity in breast cancer has been the limited throughput, accuracy and reproducibility of measuring tissue markers. Computerized image analysis systems may help address these concerns but published reports of their use are limited. We assessed agreement between automated and pathologist scores of a diverse set of immunohistochemical (IHC) assays performed on breast cancer TMAs. TMAs of 440 breast cancers previously stained for ER-?, PR, HER-2, ER-? and aromatase were independently scored by two pathologists and three automated systems (TMALabII, TMAx, Ariol). Agreement between automated and pathologist scores of negative/positive was measured using the area under the receiver operator characteristics curve (AUC) and weighted kappa statistics (?) for categorical scores. We also investigated the correlation between IHC scores and mRNA expression levels. Agreement between pathologist and automated negative/positive and categorical scores was excellent for ER-? and PR (AUC range =0.98-0.99; ? range =0.86-0.91). Lower levels of agreement were seen for ER-? categorical scores (AUC=0.99-1.0; ?=0.80-0.86) and both negative/positive and categorical scores for aromatase (AUC=0.85-0.96; ?=0.41-0.67) and HER2 (AUC=0.94-0.97; ?=0.53-0.72). For ER-? and PR, there was strong correlation between mRNA levels and automated (?=0.67-0.74) and pathologist IHC scores (?=0.67-0.77). HER2 mRNA levels were more strongly correlated with pathologist (?=0.63) than automated IHC scores (?=0.41-0.49). Automated analysis of IHC markers is a promising approach for scoring large numbers of breast cancer tissues in epidemiologic investigations. This would facilitate studies of etiologic heterogeneity which ultimately may allow improved risk prediction and better prevention approaches.

Bolton, Kelly L.; Garcia-Closas, Montserrat; Pfeiffer, Ruth M.; Duggan, Maire A.; Howat, William J.; Hewitt, Stephen M.; Yang, Xiaohong R.; Cornelison, Robert; Anzick, Sarah L.; Meltzer, Paul; Davis, Sean; Lenz, Petra; Figueroa, Jonine D.; Pharoah, Paul D.P.; Sherman, Mark E.

2010-01-01

92

Cathepsin D Expression in Colorectal Cancer: From Proteomic Discovery through Validation Using Western Blotting, Immunohistochemistry, and Tissue Microarrays  

PubMed Central

Despite recent advances in surgical techniques and therapeutic treatments, survival from colorectal cancer (CRC) remains disappointing with some 40–50% of newly diagnosed patients ultimately dying of metastatic disease. Current staging by light microscopy alone is not sufficiently predictive of prognosis and would benefit from additional support from biomarkers in order to stratify patients appropriately for adjuvant therapy. We have identified that cathepsin D expression was significantly greater in cells from invasive front (IF) area and liver metastasis (LM) than those from main tumour body (MTB). Cathepsin D expression was subsequently examined by immunohistochemistry in tissue microarrays from 119 patients with CRC. Strong expression in tumour cells at the IF did not correlate significantly with any clinico-pathological parameters examined or patient survival. However, cathepsin D expression in cells from the MTB was highly elevated in late stage CRC and showed significant correlation with subsequent distant metastasis and shorter cancer-specific survival. We also found that macrophages surrounding tumour cells stained strongly for cathepsin D but there was no significant correlation found between cathepsin D in macrophages at IF and MTB of CRC patient with the clinic-pathological parameters examined.

Kirana, Chandra; Shi, Hongjun; Laing, Emma; Hood, Kylie; Miller, Rose; Bethwaite, Peter; Keating, John; Jordan, T. William; Hayes, Mark; Stubbs, Richard

2012-01-01

93

Large-scale meta-analysis of cancer microarray data identifies common transcriptional profiles of neoplastic transformation and progression  

Microsoft Academic Search

Many studies have used DNA microarrays to identify the gene expression signatures of human cancer, yet the critical features of these often unmanageably large signatures remain elusive. To address this, we developed a statistical method, comparative metaprofiling, which identifies and assesses the intersection of multiple gene expression signatures from a diverse collection of microarray data sets. We collected and analyzed

Daniel R. Rhodes; K. Shanker; Nandan Deshpande; Radhika Varambally; Debashis Ghosh; Terrence Barrette; Akhilesh Pandey; Arul M. Chinnaiyan

2004-01-01

94

Comparison of quantum dots immunofluorescence histochemistry and conventional immunohistochemistry for the detection of caveolin-1 and PCNA in the lung cancer tissue microarray  

Microsoft Academic Search

Luminescent semiconductor quantum dots (QDs) are a new class of fluorescent label with wide ranges of applications in cell\\u000a imaging. In this study, we evaluated the capability of QDs immunofluorescence histochemistry (QDs-IHC) for detecting antigens\\u000a of caveolin-1 and PCNA in the lung cancer tissue microarray (TMA) in comparison with the conventional immunohistochemistry\\u000a (IHC) technique. Both methods revealed consistent antigen localization

Honglei Chen; Jingling Xue; Yuxia Zhang; Xiaobo Zhu; Jun Gao; Baoping Yu

2009-01-01

95

ImageMiner: a software system for comparative analysis of tissue microarrays using content-based image retrieval, high-performance computing, and grid technology  

Microsoft Academic Search

Objective and designThe design and implementation of ImageMiner, a software platform for performing comparative analysis of expression patterns in imaged microscopy specimens such as tissue microarrays (TMAs), is described. ImageMiner is a federated system of services that provides a reliable set of analytical and data management capabilities for investigative research applications in pathology. It provides a library of image processing

David J Foran; Lin Yang; Wenjin Chen; Jun Hu; Lauri A Goodell; Michael Reiss; Fusheng Wang; Tahsin Kurc; Tony Pan; Ashish Sharma; Joel H Saltz

2011-01-01

96

Immunohistochemical expression of minichromosome maintenance complex protein 2 predicts biochemical recurrence in prostate cancer: a tissue microarray and digital imaging analysis-based study of 428 cases.  

PubMed

Prostate cancer remains a major health problem in the United States. Established clinicopathologic parameters such as Gleason score, T stage, and prostate-specific antigen levels are currently the guiding tools for prognostication and disease management. The addition of biomarkers could increase the accuracy of these parameters for predicting disease progression, response to therapy, and survival. In this regard, the goal of this study was to evaluate minichromosome maintenance complex protein 2 and Ki-67 immunohistochemical expression as predictors of outcome in prostate cancer. For this purpose, 11 tissue microarrays were constructed using tumor and nontumor samples from 428 patients. Patients were divided into short-term (mean, 2.9 years) and long-term (mean, 14.1 years) follow-up groups. End points were biochemical recurrence for the short-term follow-up group and prostate cancer-related death for the long-term follow-up group. All men in the long-term follow-up group had biochemical recurrence at the time of recruitment. Expression of both markers was higher in tumor than in nontumor glands. Percentage of minichromosome maintenance complex protein 2 was associated with Gleason score in both groups. Percentage of Ki-67 was associated with Gleason score and pathologic stage only in the short-term follow-up group. Higher minichromosome maintenance complex protein 2 percentages were associated with biochemical recurrence in the short-term follow-up group. In the long-term follow-up group, neither minichromosome maintenance complex protein 2 nor Ki-67 levels predicted prostate cancer death. In conclusion, our results suggest that in patients treated by radical prostatectomy for clinically localized prostate cancer, immunohistochemistry for minichromosome maintenance complex protein 2 expression could be used to predict biochemical recurrence, independent of other known clinicopathologic factors. PMID:22554381

Toubaji, Antoun; Sutcliffe, Siobhan; Chaux, Alcides; Lecksell, Kristen; Hicks, Jessica; De Marzo, Angelo M; Platz, Elizabeth A; Netto, George J

2012-05-02

97

A model for the design and construction of a resource for the validation of prognostic prostate cancer biomarkers: the Canary Prostate Cancer Tissue Microarray.  

PubMed

Tissue microarrays (TMAs) provide unique resources for rapid evaluation and validation of tissue biomarkers. The Canary Foundation Retrospective Prostate Tissue Microarray Resource used a rigorous statistical design, quota sampling, a variation of the case-cohort study, to select patients for inclusion in a multicenter, retrospective prostate cancer TMA cohort. The study is designed to definitively validate tissue biomarkers of prostate cancer recurrence after radical prostatectomy. Tissue samples from over 1000 participants treated for prostate cancer with radical prostatectomy between 1995 and 2004 were selected at 6 participating institutions in the United States and Canada. This design captured the heterogeneity of screening and clinical practices in the contemporary North American population. Standardized clinical data were collected in a centralized database. The project has been informative in several respects. The scale and complexity of assembling TMAs with over 200 cases at each of 6 sites involved unanticipated levels of effort and time. Our statistical design promises to provide a model for outcome-based studies where tissue localization methods are applied to high-density TMAs. PMID:23232570

Hawley, Sarah; Fazli, Ladan; McKenney, Jesse K; Simko, Jeff; Troyer, Dean; Nicolas, Marlo; Newcomb, Lisa F; Cowan, Janet E; Crouch, Luis; Ferrari, Michelle; Hernandez, Javier; Hurtado-Coll, Antonio; Kuchinsky, Kyle; Liew, Janet; Mendez-Meza, Rosario; Smith, Elizabeth; Tenggara, Imelda; Zhang, Xiaotun; Carroll, Peter R; Chan, June M; Gleave, Martin; Lance, Raymond; Lin, Daniel W; Nelson, Peter S; Thompson, Ian M; Feng, Ziding; True, Lawrence D; Brooks, James D

2013-01-01

98

HER2 in Gastric Cancer: An Immunohistochemical Study on Tissue Microarrays and the Coressponding Whole-Tissue Sections with a Supplemental Fish Study.  

PubMed

Since focal HER2 expression is an issue in GC, TMA construction from the paraffin-embedded surgically-obtained tissue may not reflect its real status. The aim of this study was to assess the HER2 status in tissue microarrays (TMAs) and the corresponding whole sections using HercepTest immunohistochemistry (IHC), and to correlate it and to assess the concordance of HER2 IHC and fluorescence in situ hybridization (FISH) in TMAs. Concordance of the HER2 expression status for 302 cases of gastric cancer using 9 paired TMAs was evaluated using a 2-mm core size and 305 corresponding whole sections. Concordance of the IHC and FISH HER2 status was compared. In addition,, the HER2 status was compared to clinicopathological characteristics and patients' survival. Using the whole-section approach, HER2 over-expression was found in 25.2 % (HER2 3+ 6.6 %, HER2 2+ 18.7 %) of tumours. The overall concordance of IHC between the cores and the whole section was 84.9 %; 15.1 % of the tumours showed HER2 amplification. The overall concordance of IHC and FISH on cores was 75.7 %. The level of amplification correlated with the IHC score. Relationship between the intestinal and papillary types and tumour grade was observed for tumours with over-expression and amplification, whereas tumour location was related only to over-expression. There was a statistically significant difference in the overall survival of the patients, which was related to HER2 amplification. In conclusion, good concordance of the IHC HER2 results between tissue cores in TMA and whole sections, and excellent concordance of the IHC and FISH results on tissue cores was found. At least a part of the observed IHC HER2 heterogeneity could very likely be explained by fixation artifacts. With adequate fixation, a higher concordance of IHC HER2 between the cores and the whole sections can be expected. The TMA approach could enable an easier analysis of more than one representative tumour block. PMID:23800891

Gasljevic, Gorana; Lamovec, Janez; Contreras, Juan Antonio; Zadnik, Vesna; Blas, Mateja; Gasparov, Slavko

2013-06-26

99

Evaluation of the expression of integrins and cell adhesion molecules through tissue microarray in lymph node metastases of prostate cancer  

PubMed Central

Background: Integrins and adhesion molecules are responsible for the maintenance of the epithelial phenotype. Cell culture studies have reported the correlation between adhesion molecule expression and prostate carcinoma, but their role in the metastatic process is not yet known. Our aim is to study the expression profiles of these molecules and evaluate their association with the metastatic behavior of prostate adenocarcinoma. Materials and Methods: A Tissue Microarray containing two samples from 19 primary tumors and one from their corresponding lymph node metastases was constructed and subjected to immunohistochemical analysis of the expression of integrins, E-cadherin and ? and ?-catenins. Within each case, paired analyses were also performed to evaluate gains or losses in metastasis compared to its primary tumor. Results: The expression of ?v, ?v?3, ?2?1 and ?-catenin were abnormal in almost every case. Marked loss of E-cadherin and ?4 integrin was found in primary and metastatic lesions. ?-catenin was normal in all primary cases and in 94% of metastases. ?6 was normal in all primary tumors and metastases. ?3 and ?3?1 were normal in 32% of primary cases and in 53% and 6% of metastases, respectively. In paired analyses, loss of E-cadherin, ?4, ?v, ?3?1 and ?v?3 was found in 65%, 71%, 59%, 53% and 47% of patients, respectively. Catenins and ?2?1 showed maintenance of expression in most of the cases. Conclusions: In this preliminary study we have shown that the loss of cell adhesion molecules can be considered a characteristic of the metastatic phenotype in prostate cancer. Larger series should be evaluated in order to confirm our findings.

Reis, Sabrina Thalita; Dall'Oglio, Marcos; de Oliveira, Luis Carlos Neves; Cury, Jose; Carvalho, Paulo Afonso; Ribeiro-Filho, Leopoldo Alves; Leite, Katia Ramos Moreira; Srougi, Miguel

2009-01-01

100

Gene network analyses point to the importance of human tissue kallikreins in melanoma progression  

PubMed Central

Background A wide variety of high-throughput microarray platforms have been used to identify molecular targets associated with biological and clinical tumor phenotypes by comparing samples representing distinct pathological states. Methods The gene expression profiles of human cutaneous melanomas were determined by cDNA microarray analysis. Next, a robust analysis to determine functional classifications and make predictions based on data-oriented hypotheses was performed. Relevant networks that may be implicated in melanoma progression were also considered. Results In this study we aimed to analyze coordinated gene expression changes to find molecular pathways involved in melanoma progression. To achieve this goal, ontologically-linked modules with coordinated expression changes in melanoma samples were identified. With this approach, we detected several gene networks related to different modules that were induced or repressed during melanoma progression. Among them we observed high coordinated expression levels of genes involved in a) cell communication (KRT4, VWF and COMP); b) epidermal development (KLK7, LAMA3 and EVPL); and c) functionally related to kallikreins (EVPL, KLK6, KLK7, KLK8, SERPINB13, SERPING1 and SLPI). Our data also indicated that hKLK7 protein expression was significantly associated with good prognosis and survival. Conclusions Our findings, derived from a different type of analysis of microarray data, highlight the importance of analyzing coordinated gene expression to find molecular pathways involved in melanoma progression.

2011-01-01

101

Progress on thermobrachytherapy surface applicator for superficial tissue disease  

NASA Astrophysics Data System (ADS)

This work reports the ongoing development of a combination applicator for simultaneous heating of superficial tissue disease using a 915 MHz DCC (dual concentric conductor) array and High Dose Rate (HDR) brachytherapy delivered via an integrated conformal catheter array. The progress includes engineering design changes in the waterbolus, DCC configurations and fabrication techniques of the conformal multilayer applicator. The dosimetric impact of the thin copper DCC array is also assessed. Steady state fluid dynamics of the new waterbolus bag indicates nearly uniform flow with less than 1°C variation across a large (19×32cm) bolus. Thermometry data of the torso phantom acquired with computer controlled movement of fiberoptic temperature probes inside thermal mapping catheters indicate feasibility of real time feedback control for the DCC array. MR (magnetic resonance) scans of a torso phantom indicate that the waterbolus thickness across the treatment area is controlled by the pressure applied by the surrounding inflatable airbladder and applicator securing straps. The attenuation coefficient of the DCC array was measured as 3+/- 0.001% and 2.95+/-0.03 % using an ion chamber and OneDose dosimeters respectively. The performance of the combination applicator on patient phantoms provides valuable feedback to optimize the applicator prior use in the patient clinic.

Arunachalam, Kavitha; Craciunescu, Oana I.; Maccarini, Paolo F.; Schlorff, Jaime L.; Markowitz, Edward; Stauffer, Paul R.

2009-02-01

102

A pig multi-tissue normalised cDNA library: large-scale sequencing, cluster analysis and 9K micro-array resource generation  

PubMed Central

Background Domestic animal breeding and product quality improvement require the control of reproduction, nutrition, health and welfare in these animals. It is thus necessary to improve our knowledge of the major physiological functions and their interactions. This would be greatly enhanced by the availability of expressed gene sequences in the databases and by cDNA arrays allowing the transcriptome analysis of any function. The objective within the AGENAE French program was to initiate a high-throughput cDNA sequencing program of a 38-tissue normalised library and generate a diverse microarray for transcriptome analysis in pig species. Results We constructed a multi-tissue cDNA library, which was normalised and subtracted to reduce the redundancy of the clones. Expressed Sequence Tags were produced and 24449 high-quality sequences were released in EMBL database. The assembly of all the public ESTs (available through SIGENAE website) resulted in 40786 contigs and 54653 singletons. At least one Agenae sequence is present in 11969 contigs (12.5%) and in 9291 of the deeper-than-one-contigs (22.8%). Sequence analysis showed that both normalisation and subtraction processes were successful and that the initial tissue complexity was maintained in the final libraries. A 9K nylon cDNA microarray was produced and is available through CRB-GADIE. It will allow high sensitivity transcriptome analyses in pigs. Conclusion In the present work, a pig multi-tissue cDNA library was constructed and a 9K cDNA microarray designed. It contributes to the Expressed Sequence Tags pig data, and offers a valuable tool for transcriptome analysis.

Bonnet, Agnes; Iannuccelli, Eddie; Hugot, Karine; Benne, Francis; Bonaldo, Maria F; Soares, Marcelo B; Hatey, Francois; Tosser-Klopp, Gwenola

2008-01-01

103

Expression of immunohistochemical markers in primary and metastatic malignant melanoma: a comparative study in 70 patients using a tissue microarray technique.  

PubMed

Melanoma can show a broad spectrum of immunoreactivity and exhibit aberrant expression of antigens or changes in immunophenotype, particularly at metastatic sites. We studied 70 primary melanomas and their metastases with a broad panel of immunohistochemical markers using a tissue microarray technique to determine possible antigenic shift between the primary lesions and their metastases. Representative tissue cores were taken and processed from each case, and the tissue microarrays were stained by standard methods using antibodies to vimentin, bcl-2, CD117, carcinoembryonic antigen, epithelial membrane antigen, S-100 protein, HMB-45, cytokeratin AE1/AE3, Melan-A, TTF-1, CD99, and tyrosinase. Histologically, all the melanomas were of the classic epithelioid type. A slight increase in the expression of Melan-A was noted in metastatic lesions as opposed to the primary tumors (63% vs. 48.4%). Expression of other melanoma-associated markers, including S-100 protein and tyrosinase was only slightly decreased at metastatic sites as opposed to the primary tumor. Increased aberrant expression of epithelial-associated markers, including epithelial membrane antigen and cytokeratin AE1/AE3 was also noted in the metastases. bcl-2, CD117, and TTF-1 also showed a modest increase in antigenic expression at metastatic sites over the primary lesions. The results of this study demonstrated minimal antigenic shift between primary and metastatic melanoma for some of the more conventional melanocytic markers, it showed increased expression of aberrant markers and oncogene expression at metastatic sites. PMID:18091385

Plaza, Jose Antonio; Suster, David; Perez-Montiel, Delia

2007-12-01

104

CD90 is Identified as a Candidate Marker for Cancer Stem Cells in Primary High-Grade Gliomas Using Tissue Microarrays*  

PubMed Central

Although CD90 has been identified as a marker for various kinds of stem cells including liver cancer stem cells (CSCs) that are responsible for tumorigenesis, the potential role of CD90 as a marker for CSCs in gliomas has not been characterized. To address the issue, we investigated the expression of CD90 in tissue microarrays containing 15 glioblastoma multiformes (GBMs), 19 WHO grade III astrocytomas, 13 WHO grade II astrocytomas, 3 WHO grade I astrocytomas and 8 normal brain tissues. Immunohistochemical analysis showed that CD90 was expressed at a medium to high level in all tested high-grade gliomas (grade III and GBM) whereas it was barely detectable in low-grade gliomas (grade I and grade II) and normal brains. Double immunofluorescence staining for CD90 and CD133 in GBM tissues revealed that CD133+ CSCs are a subpopulation of CD90+ cells in GBMs in vivo. Flow cytometry analysis of the expression of CD90 and CD133 in GBM-derived stem-like neurospheres further confirmed the conclusion in vitro. The expression levels of both CD90 and CD133 were reduced along with the loss of stem cells after differentiation. Furthermore, the limiting dilution assay demonstrated that the sphere formation ability was comparable between the CD90+/CD133+ and the CD90+/CD133? populations of GBM neurospheres, which is much higher than that of the CD90?/CD133? population. We also performed double staining for CD90 and a vascular endothelial cell marker CD31 in tissue microarrays which revealed that the CD90+ cells were clustered around the tumor vasculatures in high-grade glioma tissues. These findings suggest that CD90 is not only a potential prognostic marker for high-grade gliomas but also a marker for CSCs within gliomas, and it resides within endothelial niche and may also play a critical role in the generation of tumor vasculatures via differentiation into endothelial cells.

He, Jintang; Liu, Yashu; Zhu, Thant; Zhu, Jianhui; DiMeco, Francesco; Vescovi, Angelo L.; Heth, Jason A.; Muraszko, Karin M.; Fan, Xing; Lubman, David M.

2012-01-01

105

CD90 is identified as a candidate marker for cancer stem cells in primary high-grade gliomas using tissue microarrays.  

PubMed

Although CD90 has been identified as a marker for various kinds of stem cells including liver cancer stem cells (CSCs) that are responsible for tumorigenesis, the potential role of CD90 as a marker for CSCs in gliomas has not been characterized. To address the issue, we investigated the expression of CD90 in tissue microarrays containing 15 glioblastoma multiformes (GBMs), 19 WHO grade III astrocytomas, 13 WHO grade II astrocytomas, 3 WHO grade I astrocytomas and 8 normal brain tissues. Immunohistochemical analysis showed that CD90 was expressed at a medium to high level in all tested high-grade gliomas (grade III and GBM) whereas it was barely detectable in low-grade gliomas (grade I and grade II) and normal brains. Double immunofluorescence staining for CD90 and CD133 in GBM tissues revealed that CD133(+) CSCs are a subpopulation of CD90(+) cells in GBMs in vivo. Flow cytometry analysis of the expression of CD90 and CD133 in GBM-derived stem-like neurospheres further confirmed the conclusion in vitro. The expression levels of both CD90 and CD133 were reduced along with the loss of stem cells after differentiation. Furthermore, the limiting dilution assay demonstrated that the sphere formation ability was comparable between the CD90(+)/CD133(+) and the CD90(+)/CD133(-) populations of GBM neurospheres, which is much higher than that of the CD90(-)/CD133(-) population. We also performed double staining for CD90 and a vascular endothelial cell marker CD31 in tissue microarrays which revealed that the CD90(+) cells were clustered around the tumor vasculatures in high-grade glioma tissues. These findings suggest that CD90 is not only a potential prognostic marker for high-grade gliomas but also a marker for CSCs within gliomas, and it resides within endothelial niche and may also play a critical role in the generation of tumor vasculatures via differentiation into endothelial cells. PMID:22203689

He, Jintang; Liu, Yashu; Zhu, Thant; Zhu, Jianhui; Dimeco, Francesco; Vescovi, Angelo L; Heth, Jason A; Muraszko, Karin M; Fan, Xing; Lubman, David M

2011-12-27

106

Oligonucleotide microarray analysis of distinct gene expression patterns in colorectal cancer tissues harboring BRAF and K-ras mutations  

Microsoft Academic Search

Various types of human cancers harbor BRAF somatic mutations, leading researchers to seek molecular targets for BRAF inhibitors. A mutually exclusive relationship has been observed between the BRAF-V600E mutation and K-ras mutations, suggesting that the BRAF-V600E mutation may differ from the other BRAF mutant types. Here, we used microarray analysis to examine differences between the BRAF and K-ras mutant colorectal

Il-Jin Kim; Hio Chung Kang; Sang-Geun Jang; Kun Kim; Sun-A Ahn; Hyun-Ju Yoon; Sang Nam Yoon; Jae-Gahb Park

107

Robotic Multimodality Stereotactic Brain Tissue Identification: Work in Progress  

Microsoft Academic Search

Real-time identification of tissue would improve procedures such as stereotactic brain biopsy (SBX), functional and implantation neurosurgery, and brain tumor excision. To standard SBX equipment has been added: (1) computer-controlled stepper motors to drive the biopsy needle\\/probe precisely; (2) multiple microprobes to track tissue density, detect blood vessels and changes in blood flow, and distinguish the various tissues being penetrated;

R. Andrews; R. Mah; A. Galvagni; M. Guerrero; R. Papasin; M. Wallace; J. Winters

1997-01-01

108

Expression Microarray Meta-Analysis Identifies Genes Associated with Ras/MAPK and Related Pathways in Progression of Muscle-Invasive Bladder Transition Cell Carcinoma  

PubMed Central

The effective detection and management of muscle-invasive bladder Transition Cell Carcinoma (TCC) continues to be an urgent clinical challenge. While some differences of gene expression and function in papillary (Ta), superficial (T1) and muscle-invasive (?T2) bladder cancers have been investigated, the understanding of mechanisms involved in the progression of bladder tumors remains incomplete. Statistical methods of pathway-enrichment, cluster analysis and text-mining can extract and help interpret functional information about gene expression patterns in large sets of genomic data. The public availability of patient-derived expression microarray data allows open access and analysis of large amounts of clinical data. Using these resources, we investigated gene expression differences associated with tumor progression and muscle-invasive TCC. Gene expression was calculated relative to Ta tumors to assess progression-associated differences, revealing a network of genes related to Ras/MAPK and PI3K signaling pathways with increased expression. Further, we identified genes within this network that are similarly expressed in superficial Ta and T1 stages but altered in muscle-invasive T2 tumors, finding 7 genes (COL3A1, COL5A1, COL11A1, FN1, ErbB3, MAPK10 and CDC25C) whose expression patterns in muscle-invasive tumors are consistent in 5 to 7 independent outside microarray studies. Further, we found increased expression of the fibrillar collagen proteins COL3A1 and COL5A1 in muscle-invasive tumor samples and metastatic T24 cells. Our results suggest that increased expression of genes involved in mitogenic signaling may support the progression of muscle-invasive bladder tumors that generally lack activating mutations in these pathways, while expression changes of fibrillar collagens, fibronectin and specific signaling proteins are associated with muscle-invasive disease. These results identify potential biomarkers and targets for TCC treatments, and provide an integrated systems-level perspective of TCC pathobiology to inform future studies.

Ewald, Jonathan A.; Downs, Tracy M.; Cetnar, Jeremy P.; Ricke, William A.

2013-01-01

109

Tissue Microarray Validation of Epidermal Growth Factor Receptor and SALL2 in Synovial Sarcoma with Comparison to Tumors of Similar Histology  

PubMed Central

Histological diagnosis of synovial sarcoma can be difficult. Genome-wide expression profiling has identified a number of genes expressed at higher levels in synovial sarcoma than in other soft tissue tumors, representing excellent candidates for diagnostic immunohistochemical markers. A tissue microarray comprising 77 sarcomas, including 46 synovial sarcomas, was constructed to validate identified markers and investigate their expression in tumors in the differential diagnosis of synovial sarcoma. Immunostaining was performed for two such markers, epidermal growth factor receptor and SAL (drosophila)-like 2 (SALL2), and for fifteen established markers used in the differential diagnosis of sarcomas. As predicted by expression profiling, epidermal growth factor receptor (a potential therapeutic target) and SALL2 stained most cases of synovial sarcoma; staining was significantly less common among other tested sarcomas. Hierarchical clustering analysis applied to immunostaining results for all 18 antibodies showed that synovial sarcomas, leiomyosarcomas, hemangiopericytomas, and solitary fibrous tumors cluster distinctly, and assigned one case with indeterminate histology as a Ewing sarcoma. Digital images from over 2500 immunostained cores analyzed in this study were captured and are made accessible through the accompanying website: http://microarray-pubs.stanford.edu/tma_portal/synsarc.

Nielsen, Torsten O.; Hsu, Forrest D.; O'Connell, John X.; Gilks, C. Blake; Sorensen, Poul H.B.; Linn, Sabine; West, Robert B.; Liu, Chih Long; Botstein, David; Brown, Patrick O.; van de Rijn, Matt

2003-01-01

110

Gene Therapy Progress and Prospects: In tissue engineering  

Microsoft Academic Search

Tissue engineering (TE) has existed for several years as an area spanning many disciplines, including medicine and engineering. The use of stem cells as a biological basis for TE coupled with advances in materials science has opened up an entirely new chapter in medicine and holds the promise of major contributions to the repair, replacement and regeneration of damaged tissues

J Polak; L Hench

2005-01-01

111

Normal morphogenesis of epithelial tissues and progression of epithelial tumors  

PubMed Central

Epithelial cells organize into various tissue architectures that largely maintain their structure throughout the life of an organism. For decades, the morphogenesis of epithelial tissues has fascinated scientists at the interface of cell, developmental, and molecular biology. Systems biology offers ways to combine knowledge from these disciplines by building integrative models that are quantitative and predictive. Can such models be useful for gaining a deeper understanding of epithelial morphogenesis? Here, we take inventory of some recurring themes in epithelial morphogenesis that systems approaches could strive to capture. Predictive understanding of morphogenesis at the systems level would prove especially valuable for diseases such as cancer, where epithelial tissue architecture is profoundly disrupted.

Wang, Chun-Chao; Jamal, Leen; Janes, Kevin A.

2011-01-01

112

Progress and opportunities for tissue-engineered skin  

NASA Astrophysics Data System (ADS)

Tissue-engineered skin is now a reality. For patients with extensive full-thickness burns, laboratory expansion of skin cells to achieve barrier function can make the difference between life and death, and it was this acute need that drove the initiation of tissue engineering in the 1980s. A much larger group of patients have ulcers resistant to conventional healing, and treatments using cultured skin cells have been devised to restart the wound-healing process. In the laboratory, the use of tissue-engineered skin provides insight into the behaviour of skin cells in healthy skin and in diseases such as vitiligo, melanoma, psoriasis and blistering disorders.

MacNeil, Sheila

2007-02-01

113

Microarray analysis of spaceflown murine thymus tissue reveals changes in gene expression regulating stress and glucocorticoid receptors.  

PubMed

The detrimental effects of spaceflight and simulated microgravity on the immune system have been extensively documented. We report here microarray gene expression analysis, in concert with quantitative RT-PCR, in young adult C57BL/6NTac mice at 8 weeks of age after exposure to spaceflight aboard the space shuttle (STS-118) for a period of 13 days. Upon conclusion of the mission, thymus lobes were extracted from space flown mice (FLT) as well as age- and sex-matched ground control mice similarly housed in animal enclosure modules (AEM). mRNA was extracted and an automated array analysis for gene expression was performed. Examination of the microarray data revealed 970 individual probes that had a 1.5-fold or greater change. When these data were averaged (n = 4), we identified 12 genes that were significantly up- or down-regulated by at least 1.5-fold after spaceflight (P < or = 0.05). The genes that significantly differed from the AEM controls and that were also confirmed via QRT-PCR were as follows: Rbm3 (up-regulated) and Hsph110, Hsp90aa1, Cxcl10, Stip1, Fkbp4 (down-regulated). QRT-PCR confirmed the microarray results and demonstrated additional gene expression alteration in other T cell related genes, including: Ctla-4, IFN-alpha2a (up-regulated) and CD44 (down-regulated). Together, these data demonstrate that spaceflight induces significant changes in the thymic mRNA expression of genes that regulate stress, glucocorticoid receptor metabolism, and T cell signaling activity. These data explain, in part, the reported systemic compromise of the immune system after exposure to the microgravity of space. PMID:20213684

Lebsack, Ty W; Fa, Vuna; Woods, Chris C; Gruener, Raphael; Manziello, Ann M; Pecaut, Michael J; Gridley, Daila S; Stodieck, Louis S; Ferguson, Virginia L; Deluca, Dominick

2010-05-15

114

Suppression of Breast Cancer Progression by Tissue Factor.  

National Technical Information Service (NTIS)

Tissue Factor (TF) is the cell surface receptor that activates coagulation by binding the serine protease coagulation factor VIIa (VIIa). The activation of the coagulation cascade leads to thrombin generation, fibrin formation and platelet activation whic...

W. Ruf

2004-01-01

115

Profiling and Verification of Gene Expression Patterns in Normal and Malignant Human Prostate Tissues by cDNA Microarray Analysis1  

PubMed Central

Abstract cDNA microarray technology allows the “profiling” of gene expression patterns for virtually any cellular material. In this study, we applied cDNA microarray technology to profile changes in gene expression associated with human prostate tumorigenesis. RNA prepared from normal and malignant prostate tissue was examined for the expression levels of 588 human genes. Four different methods for data normalization were utilized. Of these, normalization to ACTB expression proved to be the most rigorous technique with the least probability of producing spurious results. After normalization to ACTB expression, 15 of 588 (2.6%) genes examined by array analysis were differentially expressed by a factor of 2x or more in malignant compared to normal prostate tissues. The expression patterns for 8 of 15 genes have been reported previously in prostate tissues (TGF?3, TGFBR3, IGFII, IGFBP2, VEGF, FGF7, ERBB3, MYC), but those of seven genes are reported here for the first time (MLH1, CYP1B1, RFC4, EPHB3, MGST1, BTEB2, MLP). These genes describe at least four metabolic and signaling pathways likely disrupted in human prostate tumorigenesis. Reverse transcriptase polymerase chain reaction (RT-PCR) and Northern blot analyses quantitated with reference to ACTB expression levels verified the trends in gene expression levels observed by array analysis for 14/15 and 8/8 genes, respectively. However, RT-PCR and Northern blot analyses accurately verified the “fold” differences in expression levels for only 6/15 (40%) and 7/8 (88%) of genes examined, respectively, demonstrating the need to better validate quantitative differences in gene expression revealed by array-based techniques.

Chaib, Hassan; Cockrell, Erin K; Rubin, Mark A; Macoska, Jill A

2001-01-01

116

Tissue engineering and regenerative medicine: history, progress, and challenges.  

PubMed

The past three decades have seen the emergence of an endeavor called tissue engineering and regenerative medicine in which scientists, engineers, and physicians apply tools from a variety of fields to construct biological substitutes that can mimic tissues for diagnostic and research purposes and can replace (or help regenerate) diseased and injured tissues. A significant portion of this effort has been translated to actual therapies, especially in the areas of skin replacement and, to a lesser extent, cartilage repair. A good amount of thoughtful work has also yielded prototypes of other tissue substitutes such as nerve conduits, blood vessels, liver, and even heart. Forward movement to clinical product, however, has been slow. Another offshoot of these efforts has been the incorporation of some new exciting technologies (e.g., microfabrication, 3D printing) that may enable future breakthroughs. In this review we highlight the modest beginnings of the field and then describe three application examples that are in various stages of development, ranging from relatively mature (skin) to ongoing proof-of-concept (cartilage) to early stage (liver). We then discuss some of the major issues that limit the development of complex tissues, some of which are fundamentals-based, whereas others stem from the needs of the end users. PMID:22432625

Berthiaume, François; Maguire, Timothy J; Yarmush, Martin L

2011-01-01

117

Modeling Inducible Human Tissue Neoplasia Identifies an Extracellular Matrix Interaction Network Involved in Cancer Progression  

PubMed Central

To elucidate mechanisms of cancer progression, we generated inducible human neoplasia in 3-dimensionally intact epithelial tissue. Gene expression profiling of both epithelia and stroma at specific time points during tumor progression revealed sequential enrichment of genes mediating discrete biologic functions in each tissue compartment. A core cancer progression signature was distilled using the increased signaling specificity of downstream oncogene effectors and subjected to network modeling. Network topology predicted that tumor development depends upon specific ECM-interacting network hubs. Blockade of one such hub, the ?1 integrin subunit, disrupted network gene expression and attenuated tumorigenesis in vivo. Thus, integrating network modeling and temporal gene expression analysis of inducible human neoplasia provides an approach to prioritize and characterize genes functioning in cancer progression. Significance Investigating tumor progression in patient samples is complicated by etiologic heterogeneity, genetic instability, and an overabundance of precursor lesions that fail to progress. These complexities obscure construction of a dynamic picture of progression from normal tissue to invasive cancer. Here, we generate inducible human neoplasia driven by conditionally active Ras and characterize the sequence of gene expression programs engaged in epithelial tumor tissue and adjacent stroma during carcinogenesis. We show that tumor-intrinsic gene expression can be refined by sufficient downstream oncogene effectors and apply a generalizable network modeling strategy to prioritize targets based upon local interconnectivity. This analysis highlights the importance of tumor-stroma interaction during tumorigenesis and identifies ? integrin as a potential oncotherapeutic that distinguishes normal and neoplastic tissue.

Reuter, Jason A.; Ortiz-Urda, Susana; Kretz, Markus; Garcia, John; Scholl, Florence A.; Pasmooij, Anna M.G.; Cassarino, David; Chang, Howard Y.; Khavari, Paul A.

2009-01-01

118

ImageMiner: a software system for comparative analysis of tissue microarrays using content-based image retrieval, high-performance computing, and grid technology  

PubMed Central

Objective and design The design and implementation of ImageMiner, a software platform for performing comparative analysis of expression patterns in imaged microscopy specimens such as tissue microarrays (TMAs), is described. ImageMiner is a federated system of services that provides a reliable set of analytical and data management capabilities for investigative research applications in pathology. It provides a library of image processing methods, including automated registration, segmentation, feature extraction, and classification, all of which have been tailored, in these studies, to support TMA analysis. The system is designed to leverage high-performance computing machines so that investigators can rapidly analyze large ensembles of imaged TMA specimens. To support deployment in collaborative, multi-institutional projects, ImageMiner features grid-enabled, service-based components so that multiple instances of ImageMiner can be accessed remotely and federated. Results The experimental evaluation shows that: (1) ImageMiner is able to support reliable detection and feature extraction of tumor regions within imaged tissues; (2) images and analysis results managed in ImageMiner can be searched for and retrieved on the basis of image-based features, classification information, and any correlated clinical data, including any metadata that have been generated to describe the specified tissue and TMA; and (3) the system is able to reduce computation time of analyses by exploiting computing clusters, which facilitates analysis of larger sets of tissue samples.

Foran, David J; Yang, Lin; Hu, Jun; Goodell, Lauri A; Reiss, Michael; Wang, Fusheng; Kurc, Tahsin; Pan, Tony; Sharma, Ashish; Saltz, Joel H

2011-01-01

119

Rat Mitochondrion-Neuron Focused Microarray (rMNChip) and Bioinformatics Tools for Rapid Identification of Differential Pathways in Brain Tissues  

PubMed Central

Mitochondrial function is of particular importance in brain because of its high demand for energy (ATP) and efficient removal of reactive oxygen species (ROS). We developed rat mitochondrion-neuron focused microarray (rMNChip) and integrated bioinformatics tools for rapid identification of differential pathways in brain tissues. rMNChip contains 1,500 genes involved in mitochondrial functions, stress response, circadian rhythms and signal transduction. The bioinformatics tool includes an algorithm for computing of differentially expressed genes, and a database for straightforward and intuitive interpretation for microarray results. Our application of these tools to RNA samples derived from rat frontal cortex (FC), hippocampus (HC) and hypothalamus (HT) led to the identification of differentially-expressed signal-transduction-bioenergenesis and neurotransmitter-synthesis pathways with a dominant number of genes (FC/HC = 55/6; FC/HT = 55/4) having significantly (p<0.05, FDR<10.70%) higher (?1.25 fold) RNA levels in the frontal cortex than the others, strongly suggesting active generation of ATP and neurotransmitters and efficient removal of ROS. Thus, these tools for rapid and efficient identification of differential pathways in brain regions will greatly facilitate our systems-biological study and understanding of molecular mechanisms underlying complex and multifactorial neurodegenerative diseases.

Su, Yan A.; Zhang, Qiuyang; Su, David M.; Tang, Michael X.

2011-01-01

120

Microarrays for Undergraduate Classes  

ERIC Educational Resources Information Center

|A microarray experiment is presented that, in six laboratory sessions, takes undergraduate students from the tissue sample right through to data analysis. The model chosen, the murine erythroleukemia cell line, can be easily cultured in sufficient quantities for class use. Large changes in gene expression can be induced in these cells by…

Hancock, Dale; Nguyen, Lisa L.; Denyer, Gareth S.; Johnston, Jill M.

2006-01-01

121

Microarrays for Undergraduate Classes  

ERIC Educational Resources Information Center

A microarray experiment is presented that, in six laboratory sessions, takes undergraduate students from the tissue sample right through to data analysis. The model chosen, the murine erythroleukemia cell line, can be easily cultured in sufficient quantities for class use. Large changes in gene expression can be induced in these cells by…

Hancock, Dale; Nguyen, Lisa L.; Denyer, Gareth S.; Johnston, Jill M.

2006-01-01

122

Tissue Engineering of Blood Vessels: Functional Requirements, Progress, and Future Challenges  

PubMed Central

Vascular disease results in the decreased utility and decreased availability of autologus vascular tissue for small diameter (< 6 mm) vessel replacements. While synthetic polymer alternatives to date have failed to meet the performance of autogenous conduits, tissue-engineered replacement vessels represent an ideal solution to this clinical problem. Ongoing progress requires combined approaches from biomaterials science, cell biology, and translational medicine to develop feasible solutions with the requisite mechanical support, a non-fouling surface for blood flow, and tissue regeneration. Over the past two decades interest in blood vessel tissue engineering has soared on a global scale, resulting in the first clinical implants of multiple technologies, steady progress with several other systems, and critical lessons-learned. This review will highlight the current inadequacies of autologus and synthetic grafts, the engineering requirements for implantation of tissue-engineered grafts, and the current status of tissue-engineered blood vessel research.

Kumar, Vivek A.; Brewster, Luke P.; Caves, Jeffrey M.; Chaikof, Elliot L.

2012-01-01

123

Hypothermia Activates Adipose Tissue to Promote Malignant Lung Cancer Progression  

PubMed Central

Microenvironment has been increasingly recognized as a critical regulator of cancer progression. In this study, we identified early changes in the microenvironment that contribute to malignant progression. Exposure of human bronchial epithelial cells (BEAS-2B) to methylnitrosourea (MNU) caused a reduction in cell toxicity and an increase in clonogenic capacity when the temperature was lowered from 37°C to 28°C. Hypothermia-incubated adipocyte media promoted proliferation in A549 cells. Although a hypothermic environment could increase urethane-induced tumor counts and Lewis lung cancer (LLC) metastasis in lungs of three breeds of mice, an increase in tumor size could be discerned only in obese mice housed in hypothermia. Similarly, coinjections using differentiated adipocytes and A549 cells promoted tumor development in athymic nude mice when adipocytes were cultured at 28°C. Conversely, fat removal suppressed tumor growth in obese C57BL/6 mice inoculated with LLC cells. Further studies show hypothermia promotes a MNU-induced epithelial-mesenchymal transition (EMT) and protects the tumor cell against immune control by TGF-?1 upregulation. We also found that activated adipocytes trigger tumor cell proliferation by increasing either TNF-? or VEGF levels. These results suggest that hypothermia activates adipocytes to stimulate tumor boost and play critical determinant roles in malignant progression.

Zhang, Yaping; Sun, Ting; Liu, Weijie; Li, Jiahuan; Liu, Yinghui; Wang, Yingying; Li, Hong; Hou, Xidong

2013-01-01

124

Hypothermia activates adipose tissue to promote malignant lung cancer progression.  

PubMed

Microenvironment has been increasingly recognized as a critical regulator of cancer progression. In this study, we identified early changes in the microenvironment that contribute to malignant progression. Exposure of human bronchial epithelial cells (BEAS-2B) to methylnitrosourea (MNU) caused a reduction in cell toxicity and an increase in clonogenic capacity when the temperature was lowered from 37°C to 28°C. Hypothermia-incubated adipocyte media promoted proliferation in A549 cells. Although a hypothermic environment could increase urethane-induced tumor counts and Lewis lung cancer (LLC) metastasis in lungs of three breeds of mice, an increase in tumor size could be discerned only in obese mice housed in hypothermia. Similarly, coinjections using differentiated adipocytes and A549 cells promoted tumor development in athymic nude mice when adipocytes were cultured at 28°C. Conversely, fat removal suppressed tumor growth in obese C57BL/6 mice inoculated with LLC cells. Further studies show hypothermia promotes a MNU-induced epithelial-mesenchymal transition (EMT) and protects the tumor cell against immune control by TGF-?1 upregulation. We also found that activated adipocytes trigger tumor cell proliferation by increasing either TNF-? or VEGF levels. These results suggest that hypothermia activates adipocytes to stimulate tumor boost and play critical determinant roles in malignant progression. PMID:24015203

Du, Gangjun; Zhao, Bei; Zhang, Yaping; Sun, Ting; Liu, Weijie; Li, Jiahuan; Liu, Yinghui; Wang, Yingying; Li, Hong; Hou, Xidong

2013-08-27

125

Microarray analysis of differentially expressed genes in vaginal tissues from women with stress urinary incontinence compared with asymptomatic women  

Microsoft Academic Search

BACKGROUND: The pathophysiology of pelvic floor dysfunction resulting in stress urinary incontinence (SUI) in women is complex. Evidence suggests that there is also a genetic predisposition towards SUI. We sought to identify differentially expressed genes involved in extracellular matrix (ECM) metabolism in vaginal tissues from women with SUI in the secretory phase of menses compared with asymptomatic women. METHODS: Tissue

Bertha Chen; Yan Wen; Zhaomei Zhang; Yaqian Guo; Janet A. Warrington

2006-01-01

126

Expression microarray meta-analysis identifies genes associated with Ras/MAPK and related pathways in progression of muscle-invasive bladder transition cell carcinoma.  

PubMed

The effective detection and management of muscle-invasive bladder Transition Cell Carcinoma (TCC) continues to be an urgent clinical challenge. While some differences of gene expression and function in papillary (Ta), superficial (T1) and muscle-invasive (?T2) bladder cancers have been investigated, the understanding of mechanisms involved in the progression of bladder tumors remains incomplete. Statistical methods of pathway-enrichment, cluster analysis and text-mining can extract and help interpret functional information about gene expression patterns in large sets of genomic data. The public availability of patient-derived expression microarray data allows open access and analysis of large amounts of clinical data. Using these resources, we investigated gene expression differences associated with tumor progression and muscle-invasive TCC. Gene expression was calculated relative to Ta tumors to assess progression-associated differences, revealing a network of genes related to Ras/MAPK and PI3K signaling pathways with increased expression. Further, we identified genes within this network that are similarly expressed in superficial Ta and T1 stages but altered in muscle-invasive T2 tumors, finding 7 genes (COL3A1, COL5A1, COL11A1, FN1, ErbB3, MAPK10 and CDC25C) whose expression patterns in muscle-invasive tumors are consistent in 5 to 7 independent outside microarray studies. Further, we found increased expression of the fibrillar collagen proteins COL3A1 and COL5A1 in muscle-invasive tumor samples and metastatic T24 cells. Our results suggest that increased expression of genes involved in mitogenic signaling may support the progression of muscle-invasive bladder tumors that generally lack activating mutations in these pathways, while expression changes of fibrillar collagens, fibronectin and specific signaling proteins are associated with muscle-invasive disease. These results identify potential biomarkers and targets for TCC treatments, and provide an integrated systems-level perspective of TCC pathobiology to inform future studies. PMID:23383328

Ewald, Jonathan A; Downs, Tracy M; Cetnar, Jeremy P; Ricke, William A

2013-02-01

127

Microarray-Based Capture of Novel Expressed Cell Type-Specific Transfrags (CoNECT) to Annotate Tissue-Specific Transcription in Drosophila melanogaster  

PubMed Central

Faithful annotation of tissue-specific transcript isoforms is important not only to understand how genes are organized and regulated but also to identify potential novel, unannotated exons of genes, which may be additional targets of mutation in disease states or while performing mutagenic screens. We have developed a microarray enrichment methodology followed by long-read, next-generation sequencing for identification of unannotated transcript isoforms expressed in two Drosophila tissues, the ovary and the testis. Even with limited sequencing, these studies have identified a large number of novel transcription units, including 5? exons and extensions, 3? exons and extensions, internal exons and exon extensions, gene fusions, and both germline-specific splicing events and promoters. Additionally, comparing our capture dataset with tiling array and traditional RNA-seq analysis, we demonstrate that our enrichment strategy is able to capture low-abundance transcripts that cannot readily be identified by the other strategies. Finally, we show that our methodology can help identify transcriptional signatures of minority cell types within the ovary that would otherwise be difficult to reveal without the CoNECT enrichment strategy. These studies introduce an efficient methodology for cataloging tissue-specific transcriptomes in which specific classes of genes or transcripts can be targeted for capture and sequence, thus reducing the significant sequencing depth normally required for accurate annotation.

Hong, X.; Doddapaneni, H.; Comeron, J. M.; Rodesch, M. J.; Halvensleben, H. A.; Nien, C. Y.; Bolei, F.; Metpally, R.; Richmond, T. A.; Albert, T. J.; Manak, J. R.

2012-01-01

128

Increasing expression of serine protease matriptase in ovarian tumors: tissue microarray analysis of immunostaining score with clinicopathological parameters  

Microsoft Academic Search

Matriptase is a type II transmembrane serine protease expressed by cells of surface epithelial origin, including epithelial ovarian tumor cells. Matriptase cleaves and activates proteins implicated in the progression of cancer and represents a potential prognostic and therapeutic target. The aim of this study was to examine the expression of matriptase in ovarian tumors and to assign clinicopathological correlations. Immunohistochemical

Jong-Shiaw Jin; Dar-Shih Hsieh; Shih-Hurng Loh; Ann Chen; Chen-Wen Yao; Chung-Yang Yen

2006-01-01

129

Friend leukaemia integration-1 expression in malignant and benign tumours: a multiple tumour tissue microarray analysis using polyclonal antibody  

PubMed Central

Background Friend leukaemia integration?1 (FLI?1) antibody is a useful marker for Ewing's sarcoma/primitive neuroectodermal tumour (EWS/PNET) and vascular tumours. However, it is also expressed in subsets of lymphoblastic lymphoma, Merkel cell carcinoma (MCC) and desmoplastic small round cell tumour (DSRCT). Aim To determine expression of FLI?1 in various benign and malignant neoplasms, by immunohistochemical analysis on 4323 tumours using multiple tumour microarrays, as well as on whole sections. Results FLI?1 was expressed in 46/62 EWS/PNETs, 2/3 olfactory neuroblastomas, 7/102 small cell carcinomas of the lung, 10/34 MCCs, 1/14 rhabdomyosarcoma, 19/132 non?Hodgkin's lymphomas, 2/3 DSRCTs, and in 53/74 benign and malignant vascular tumours. In addition, 27/508 squamous cell carcinomas, 19/837 adenocarcinomas, 10/400 urothelial bladder cancers, 1/40 basal cell carcinomas, 3/29 liposarcomas, 1/40 glioblastoma multiforme and 9/29 medullar carcinomas of the breast expressed FLI?1. The sensitivity and specificity of FLI?1 to distinguish EWS/PNET from all types of malignancies were 74.2% and 96.0%, respectively. Finally, the sensitivity and specificity of FLI?1 to distinguish EWS/PNET from other small round cell tumours (SRCTs) were 74.2% and 91.6%, respectively. Conclusion This study was the first to show that FLI?1 can be seen in a variety of solid tumours, some of which had never been explored before. This finding should be kept in mind, especially when using FLI?1 as a marker for finding the primary origin of poorly differentiated metastatic tumour. Finally, despite the expression of FLI?1 in numerous malignancies, it is still considered to be highly sensitive and specific in distinguishing EWS/PNET from other tumour types in general and from other SRCTs in particular.

Mhawech-Fauceglia, Paulette; Herrmann, Francois R; Bshara, Wiam; Odunsi, Kunle; Terracciano, Luigi; Sauter, Guido; Cheney, Richard T; Groth, Jeff

2007-01-01

130

High-resolution cDNA microarray CGH mapping of genomic imbalances in osteosarcoma using formalin-fixed paraffin-embedded tissue.  

PubMed

Formalin-fixed paraffin embedded (FFPE) tumor tissue provides an opportunity to perform retrospective genomic studies of tumors in which chromosomal imbalances are strongly associated with oncogenesis. The application of comparative genomic hybridization (CGH) has led to the rapid accumulation of cytogenetic information on osteosarcoma (OS); however, the limited resolving power of metaphase CGH does not permit precise mapping of imbalances. Array CGH allows quantitative detection and more precise delineation of copy number aberrations in tumors. Unfortunately the high cost and lower density of BACs on available commercial arrays has limited the ability to comprehensively profile copy number changes in tumors such as OS that are recurrently subject to genomic imbalance. In this study a cDNA/EST microarray including 18,980 human cDNAs (which represent all 22 pairs of autosomal chromosomes and chromosome X) was used for CGH analysis of eight OS FFPE. Chromosomes 1, 12, 17, and X harbored the most imbalances. Gain/amplification of X was observed in 4/8 OS, and in keeping with other recent genomic analyses of OS, gain/amplification of 17p11.2 was often accompanied by a distal deletion in the region of the p53 gene. Gain/amplification of the X chromosome was verified using interphase FISH carried out on a subset of OS FFPE sections and OS tissue arrays. PMID:15305059

Zielenska, M; Marrano, P; Thorner, P; Pei, J; Beheshti, B; Ho, M; Bayani, J; Liu, Y; Sun, B C; Squire, J A; Hao, X-S

2004-01-01

131

Expression profiling using human tissues in combination with RNA amplification and microarray analysis: assessment of Langerhans cell histiocytosis  

Microsoft Academic Search

Summary. Advances in molecular genetics have led to sequencing of the human genome, and expression data is becoming available for many diverse tissues throughout the body, allowing for exciting hypothesis testing of critical concepts such as development, differentiation, homeostasis, and ultimately, disease pathogenesis. At present, an optimal methodology to assess gene expression is to evaluate single cells, either identified physiologically

K. L. McClain; Y.-H. Cai; J. Hicks; L. E. Peterson; X.-T. Yan; S. Che; S. D. Ginsberg

2005-01-01

132

A Novel Survival-Based Tissue Microarray of Pancreatic Cancer Validates MUC1 and Mesothelin as Biomarkers  

Microsoft Academic Search

BackgroundOne–fifth of patients with seemingly ‘curable’ pancreatic ductal adenocarcinoma (PDA) experience an early recurrence and death, receiving no definable benefit from a major operation. Some patients with advanced stage tumors are deemed ‘unresectable’ by conventional staging criteria (e.g. liver metastasis), yet progress slowly. Effective biomarkers that stratify PDA based on biologic behavior are needed. To help researchers sort through the

Jordan M. Winter; Laura H. Tang; David S. Klimstra; Murray F. Brennan; Jonathan R. Brody; Flavio G. Rocha; Xiaoyu Jia; Li-Xuan Qin; Michael I. D’Angelica; Ronald P. DeMatteo; Yuman Fong; William R. Jarnagin; Eileen M. O’Reilly; Peter J. Allen

2012-01-01

133

Applications of condensed matter understanding to medical tissues and disease progression: Elemental analysis and structural integrity of tissue scaffolds  

NASA Astrophysics Data System (ADS)

The investigations reported herein link tissue structure and elemental presence with issues of environmental health and disease, exemplified by uptake and storage of potentially toxic elements in the body, the osteoarthritic condition and malignancy in the breast and other soft tissues. Focus is placed on application of state-of-the-art ionizing radiation techniques, including, micro-synchrotron X-ray fluorescence (?-SXRF) and particle-induced X-ray emission/Rutherford backscattering mapping (?-PIXE/RBS), coherent small-angle X-ray scattering (cSAXS) and X-ray phase-contrast imaging, providing information on elemental make-up, the large-scale organisation of collagen and anatomical features of moderate and low atomic number media. For the particular situations under investigation, use of such facilities is allowing information to be obtained at an unprecedented level of detail, yielding new understanding of the affected tissues and the progression of disease.

Bradley, D. A.; Farquharson, M. J.; Gundogdu, O.; Al-Ebraheem, Alia; Che Ismail, Elna; Kaabar, W.; Bunk, O.; Pfeiffer, F.; Falkenberg, G.; Bailey, M.

2010-02-01

134

The Effects of Progressive Anemia on Jejunal Mucosal and Serosal Tissue Oxygenation in Pigs  

Microsoft Academic Search

Anemia may promote intestinal hypoxia. We studied the effects of progressive isovolemic hemodilution on jejunal mucosal (Po,muc), and serosal tissue oxygen tension (Po,ser, Clark-type surface electrodes), muco- sal microvascular hemoglobin oxygen saturation (Hbo,muc), and hematocrit (Hctmuc; tissue reflectance spectophotometry) in a jejunal segment. Twelve do- mestic pigs were anesthetized, paralyzed, and mechan- ically ventilated. Laparatomy was performed, arterial supply of

Markus Haisjackl; Gabriele Luz; Harald Sparr; Reinhard Germann; Natalie Salak; Barbara Friesenecker; Engelbert Deusch; Stefan Meusburger; Walter Hasibeder

1997-01-01

135

Recent Progress on Tissue-Resident Adult Stem Cell Biology and Their Therapeutic Implications  

Microsoft Academic Search

Recent progress in the field of the stem cell research has given new hopes to treat and even cure diverse degenerative disorders\\u000a and incurable diseases in human. Particularly, the identification of a rare population of adult stem cells in the most tissues\\/organs\\u000a in human has emerged as an attractive source of multipotent stem\\/progenitor cells for cell replacement-based therapies and\\u000a tissue

Murielle Mimeault; Surinder K. Batra

2008-01-01

136

P-cadherin expression as a prognostic biomarker in a 3992 case tissue microarray series of breast cancer  

Microsoft Academic Search

P-cadherin is a calcium-dependent cell–cell adhesion glycoprotein. P-cadherin expression is restricted to the myoepithelial cells in normal breast tissue, and aberrant staining has also been described in invasive tumors. Several small studies have reported P-cadherin as a marker of poor outcome in breast cancer patients but its prognostic significance in relation to other variables has not been established in a

Gulisa Turashvili; Steven E McKinney; Ozge Goktepe; Samuel C Leung; David G Huntsman; Karen A Gelmon; Gerrit Los; Paul A Rejto; Samuel A J R Aparicio

2011-01-01

137

Upregulation of ASCL1 and inhibition of Notch signaling pathway characterize progressive astrocytoma  

Microsoft Academic Search

Astrocytoma is the most common type of brain cancer constituting more than half of all brain tumors. With an aim to identify markers describing astrocytoma progression, we have carried out microarray analysis of astrocytoma samples of different grades using cDNA microarray containing 1152 cancer-specific genes. Data analysis identified several differentially regulated genes between normal brain tissue and astrocytoma as well

Kumaravel Somasundaram; Sreekanth P Reddy; Katyayni Vinnakota; Ramona Britto; Madhavan Subbarayan; Sandeep Nambiar; Aparna Hebbar; Cini Samuel; Mitesh Shetty; Hari Kishore Sreepathi; Vani Santosh; Alangar Sathyaranjandas Hegde; Sridevi Hegde; Paturu Kondaiah; M R S Rao; Rao

2005-01-01

138

Microarray-based capture of novel expressed cell type-specific transfrags (CoNECT) to annotate tissue-specific transcription in Drosophila melanogaster.  

PubMed

Faithful annotation of tissue-specific transcript isoforms is important not only to understand how genes are organized and regulated but also to identify potential novel, unannotated exons of genes, which may be additional targets of mutation in disease states or while performing mutagenic screens. We have developed a microarray enrichment methodology followed by long-read, next-generation sequencing for identification of unannotated transcript isoforms expressed in two Drosophila tissues, the ovary and the testis. Even with limited sequencing, these studies have identified a large number of novel transcription units, including 5' exons and extensions, 3' exons and extensions, internal exons and exon extensions, gene fusions, and both germline-specific splicing events and promoters. Additionally, comparing our capture dataset with tiling array and traditional RNA-seq analysis, we demonstrate that our enrichment strategy is able to capture low-abundance transcripts that cannot readily be identified by the other strategies. Finally, we show that our methodology can help identify transcriptional signatures of minority cell types within the ovary that would otherwise be difficult to reveal without the CoNECT enrichment strategy. These studies introduce an efficient methodology for cataloging tissue-specific transcriptomes in which specific classes of genes or transcripts can be targeted for capture and sequence, thus reducing the significant sequencing depth normally required for accurate annotation. Ovary and testis isotigs over 200 bp have been deposited with the GenBank Transcriptome Shotgun Assembly Sequence Database as bioproject no.PRJNA89451 (accession nos. JV208106–JV230865). PMID:22908036

Hong, X; Doddapaneni, H; Comeron, J M; Rodesch, M J; Halvensleben, H A; Nien, C Y; Bolei, F; Metpally, R; Richmond, T A; Albert, T J; Manak, J R

2012-08-01

139

Microarray-based survey of CpG islands identifies concurrent hyper- and hypomethylation patterns in tissues derived from patients with breast cancer.  

PubMed

Maintenance of CpG island methylation in the genome is crucial for cellular homeostasis and this balance is disrupted in cancer. Our rationale was to compare the methylation of CpG islands in tissues (tumor, healthy breast and blood) from patients with breast cancer. We studied 72 genes in 103 samples using microarray hybridization and bisulfite sequencing. We observed tumor specific hyper- or hypomethylation of five genes; COL9A1, MT1A, MT1J, HOXA5 and FLJ45983. A general drop of methylation in COL9A1 was apparent in tumors, when compared with blood and healthy breast tissue. Furthermore, one tumor displayed a complete loss of methylation of all five genes, suggesting overall impairment of methylation. The downstream, evolutionary conserved island of HOXA5 showed hypomethylation in 18 tumors and complete methylation in others. This CpG island also displayed a semimethylated state in the majority of normal breast samples, when compared to complete methylation in blood. Distinct methylation patterns were further seen in MT1J and MT1A, belonging to the metallothionein gene family. The CpG islands of these genes are spaced by 2 kb, which shows selective methylation of two structurally and functionally related genes. The promoters of FLJ45983 and MT1A were methylated above 25% in 18 primary and metastatic tumors. Concurrently, there was also >10% methylation of healthy breast tissue in 11 and 5 samples, respectively. This suggests that the methylation process for the latter two genes takes place already in normal breast cells. Our results also point to a considerable heterogeneity of epigenetic disturbance in breast cancer. This article contains Supplementary Material available at http://www.interscience.wiley.com/jpages/1045-2257/suppmat. PMID:16575877

Piotrowski, Arkadiusz; Benetkiewicz, Magdalena; Menzel, Uwe; Díaz de Ståhl, Teresita; Mantripragada, Kiran; Grigelionis, Gintautas; Buckley, Patrick G; Jankowski, Micha?; Hoffman, Jacek; Ba?a, Dariusz; Srutek, Ewa; Laskowski, Ryszard; Zegarski, Wojciech; Dumanski, Jan P

2006-07-01

140

Combined Array Comparative Genomic Hybridization and Tissue Microarray Analysis Suggest PAK1 at 11q13.5-q14 as a Critical Oncogene Target in Ovarian Carcinoma  

PubMed Central

Amplification of chromosomal regions leads to an increase of DNA copy numbers and expression of oncogenes in many human tumors. The identification of tumor-specific oncogene targets has potential diagnostic and therapeutic implications. To identify distinct spectra of oncogenic alterations in ovarian carcinoma, metaphase comparative genomic hybridization (mCGH), array CGH (aCGH), and ovarian tumor tissue microarrays were used in this study. Twenty-six primary ovarian carcinomas and three ovarian carcinoma cell lines were analyzed by mCGH. Frequent chromosomal overrepresentation was observed on 2q (31%), 3q (38%), 5p (38%), 8q (52%), 11q (21%), 12p (21%), 17q (21%), and 20q (52%). The role of oncogenes residing in gained chromosomal loci was determined by aCGH with 59 genetic loci commonly amplified in human tumors. DNA copy number gains were most frequently observed for PIK3CA on 3q (66%), PAK1 on 11q (59%), KRAS2 on 12p (55%), and STK15 on 20q (55%). The 11q13-q14 amplicon, represented by six oncogenes (CCND1, FGF4, FGF3, EMS1, GARP, and PAK1) revealed preferential gene copy number gains of PAK1, which is located at 11q13.5-q14. Amplification and protein expression status of both PAK1 and CCND1 were further examined by fluorescence in situ hybridization and immunohistochemistry using a tissue microarray consisting of 268 primary ovarian tumors. PAK1 copy number gains were observed in 30% of the ovarian carcinomas and PAK1 protein was expressed in 85% of the tumors. PAK1 gains were associated with high grade (P < 0.05). In contrast, CCND1 gene alterations and protein expression were less frequent (10.6% and 25%, respectively), suggesting that the critical oncogene target of amplicon 11q13–14 lies distal to CCND1. This study demonstrates that aCGH facilitates further characterization of oncogene candidates residing in amplicons defined by mCGH.

Schraml, Peter; Schwerdtfeger, Georg; Burkhalter, Felix; Raggi, Anna; Schmidt, Dietmar; Ruffalo, Teresa; King, Walter; Wilber, Kim; Mihatsch, Michael J.; Moch, Holger

2003-01-01

141

Distribution of p63, cytokeratins 5\\/6 and cytokeratin 14 in 51 normal and 400 neoplastic human tissue samples using TARP4 multi-tumor tissue microarray  

Microsoft Academic Search

p63, cytokeratin (CK) 5\\/6 and CK 14 have been employed in diagnostic pathology as markers of basal, squamous and myoepithelial differentiation in several types of human neoplasms; however, there is scant data on the concurrent expression of these markers in large series of human neoplasms. We analyzed the distribution of these three immunohistochemical markers in 51 normal human tissue samples,

Jorge S. Reis-Filho; Pete T. Simpson; Albino Martins; Ana Preto; Fátima Gärtner; Fernando C. Schmitt

2003-01-01

142

Next-generation tissue microarray (ngTMA) increases the quality of biomarker studies: an example using CD3, CD8, and CD45RO in the tumor microenvironment of six different solid tumor types  

PubMed Central

Background Tissue microarray (TMA) technology revolutionized the investigation of potential biomarkers from paraffin-embedded tissues. However, conventional TMA construction is laborious, time-consuming and imprecise. Next-generation tissue microarrays (ngTMA) combine histological expertise with digital pathology and automated tissue microarraying. The aim of this study was to test the feasibility of ngTMA for the investigation of biomarkers within the tumor microenvironment (tumor center and invasion front) of six tumor types, using CD3, CD8 and CD45RO as an example. Methods Ten cases each of malignant melanoma, lung, breast, gastric, prostate and colorectal cancers were reviewed. The most representative H&E slide was scanned and uploaded onto a digital slide management platform. Slides were viewed and seven TMA annotations of 1 mm in diameter were placed directly onto the digital slide. Different colors were used to identify the exact regions in normal tissue (n?=?1), tumor center (n?=?2), tumor front (n?=?2), and tumor microenvironment at invasion front (n?=?2) for subsequent punching. Donor blocks were loaded into an automated tissue microarrayer. Images of the donor block were superimposed with annotated digital slides. Exact annotated regions were punched out of each donor block and transferred into a TMA block. 420 tissue cores created two ngTMA blocks. H&E staining and immunohistochemistry for CD3, CD8 and CD45RO were performed. Results All 60 slides were scanned automatically (total time?tissue microarrayer, simultaneously. Alignment of donor block images and digital slides was possible in less than 2 minutes/case. Automated punching of tissue cores and transfer took 12 seconds/core. Total ngTMA construction time was 1.4 hours. Stains for H&E and CD3, CD8 and CD45RO highlighted the precision with which ngTMA could capture regions of tumor-stroma interaction of each cancer and the T-lymphocytic immune reaction within the tumor microenvironment. Conclusion Based on a manual selection criteria, ngTMA is able to precisely capture histological zones or cell types of interest in a precise and accurate way, aiding the pathological study of the tumor microenvironment. This approach would be advantageous for visualizing proteins, DNA, mRNA and microRNAs in specific cell types using in situ hybridization techniques.

2013-01-01

143

Progressive Overgrowth of the Cerebriform Connective Tissue Nevus in Patients with Proteus Syndrome  

PubMed Central

Background Proteus syndrome is a rare overgrowth disorder that almost always affects the skin. Objective Our purpose was to evaluate progression of skin lesions in patients with Proteus syndrome. Methods Skin findings were documented in 36 patients with Proteus syndrome. Progression of skin lesions in 16 of these patients was assessed by comparing photographs obtained on repeat visits for an average total duration of 53 months. Results The skin lesion most characteristic of Proteus syndrome, the cerebriform connective tissue nevus showed progression in 13 children but not in 3 adults. The cerebriform connective tissue nevus progressed by expansion into previously uninvolved skin, increased thickness, and development of new lesions. Lipomas increased in size and/or number in 8/10 children with lipomas. In contrast, epidermal nevi and vascular malformations generally did not spread or increase in number. Limitations Only 3 adults with Proteus syndrome were evaluated longitudinally. Conclusion The cerebriform connective tissue nevus in Proteus syndrome grows throughout childhood but tends to remain stable in adulthood.

Beachkofsky, Thomas M.; Sapp, Julie C.; Biesecker, Leslie G.; Darling, Thomas N.

2011-01-01

144

Up-regulation of cell cycle arrest protein BTG2 correlates with increased overall survival in breast cancer, as detected by immunohistochemistry using tissue microarray  

PubMed Central

Background Previous studies have shown that the ADIPOR1, ADORA1, BTG2 and CD46 genes differ significantly between long-term survivors of breast cancer and deceased patients, both in levels of gene expression and DNA copy numbers. The aim of this study was to characterize the expression of the corresponding proteins in breast carcinoma and to determine their correlation with clinical outcome. Methods Protein expression was evaluated using immunohistochemistry in an independent breast cancer cohort of 144 samples represented on tissue microarrays. Fisher's exact test was used to analyze the differences in protein expression between dead and alive patients. We used Cox-regression multivariate analysis to assess whether the new markers predict the survival status of the patients better than the currently used markers. Results BTG2 expression was demonstrated in a significantly lower proportion of samples from dead patients compared to alive patients, both in overall expression (P = 0.026) and cell membrane specific expression (P = 0.013), whereas neither ADIPOR1, ADORA1 nor CD46 showed differential expression in the two survival groups. Furthermore, a multivariate analysis showed that a model containing BTG2 expression in combination with HER2 and Ki67 expression along with patient age performed better than a model containing the currently used prognostic markers (tumour size, nodal status, HER2 expression, hormone receptor status, histological grade, and patient age). Interestingly, BTG2 has previously been described as a tumour suppressor gene involved in cell cycle arrest and p53 signalling. Conclusions We conclude that high-level BTG2 protein expression correlates with prolonged survival in patients with breast carcinoma.

2010-01-01

145

A Seven-Marker Signature and Clinical Outcome in Malignant Melanoma: A Large-Scale Tissue-Microarray Study with Two Independent Patient Cohorts  

PubMed Central

Background Current staging methods such as tumor thickness, ulceration and invasion of the sentinel node are known to be prognostic parameters in patients with malignant melanoma (MM). However, predictive molecular marker profiles for risk stratification and therapy optimization are not yet available for routine clinical assessment. Methods and Findings Using tissue microarrays, we retrospectively analyzed samples from 364 patients with primary MM. We investigated a panel of 70 immunohistochemical (IHC) antibodies for cell cycle, apoptosis, DNA mismatch repair, differentiation, proliferation, cell adhesion, signaling and metabolism. A marker selection procedure based on univariate Cox regression and multiple testing correction was employed to correlate the IHC expression data with the clinical follow-up (overall and recurrence-free survival). The model was thoroughly evaluated with two different cross validation experiments, a permutation test and a multivariate Cox regression analysis. In addition, the predictive power of the identified marker signature was validated on a second independent external test cohort (n?=?225). A signature of seven biomarkers (Bax, Bcl-X, PTEN, COX-2, loss of ?-Catenin, loss of MTAP, and presence of CD20 positive B-lymphocytes) was found to be an independent negative predictor for overall and recurrence-free survival in patients with MM. The seven-marker signature could also predict a high risk of disease recurrence in patients with localized primary MM stage pT1-2 (tumor thickness ?2.00 mm). In particular, three of these markers (MTAP, COX-2, Bcl-X) were shown to offer direct therapeutic implications. Conclusions The seven-marker signature might serve as a prognostic tool enabling physicians to selectively triage, at the time of diagnosis, the subset of high recurrence risk stage I–II patients for adjuvant therapy. Selective treatment of those patients that are more likely to develop distant metastatic disease could potentially lower the burden of untreatable metastatic melanoma and revolutionize the therapeutic management of MM.

Bosserhoff, Anja K.; Hofstadter, Ferdinand; Pauer, Armin; Roth, Volker; Buhmann, Joachim M.; Moll, Ingrid; Anagnostou, Nikos; Brandner, Johanna M.; Ikenberg, Kristian; Moch, Holger; Landthaler, Michael; Vogt, Thomas; Wild, Peter J.

2012-01-01

146

Can clinically relevant prognostic subsets of breast cancer patients with four or more involved axillary lymph nodes be identified through immunohistochemical biomarkers? A tissue microarray feasibility study  

PubMed Central

Introduction Primary breast cancer involving four or more axillary lymph nodes carries a poor prognosis. We hypothesized that use of an immunohistochemical biomarker scoring system could allow for identification of variable risk subgroups. Methods Patients with four or more positive axillary nodes were identified from a clinically annotated tissue microarray of formalin-fixed paraffin-embedded primary breast cancers and randomized into a 'test set' and a 'validation set'. A prospectively defined prognostic scoring model was developed in the test set and was further assessed in the validation set combining expression for eight biomarkers by immunohistochemistry, including estrogen receptor, human epidermal growth factor receptors 1 and 2, carbonic anhydrase IX, cytokeratin 5/6, progesterone receptor, p53 and Ki-67. Survival outcomes were analyzed by the Kaplan–Meier method, log rank tests and Cox proportional-hazards models. Results A total of 313 eligible patients were identified in the test set for whom 10-year relapse-free survival was 38.3% (SEM 2.9%), with complete immunohistochemical data available for 227. Tumor size, percentage of positive axillary nodes and expression status for the progesterone receptor, Ki-67 and carbonic anhydrase IX demonstrated independent prognostic significance with respect to relapse-free survival. Our combined biomarker scoring system defined three subgroups in the test set with mean 10-year relapse-free survivals of 75.4% (SEM 7.0%), 35.3% (SEM 4.1%) and 19.3% (SEM 7.0%). In the validation set, differences in relapse-free survival for these subgroups remained statistically significant but less marked. Conclusion Biomarkers assessed here carry independent prognostic value for breast cancer with four or more positive axillary nodes and identified clinically relevant prognostic subgroups. This approach requires refinement and validation of methodology.

Crabb, Simon J; Bajdik, Chris D; Leung, Samuel; Speers, Caroline H; Kennecke, Hagen; Huntsman, David G; Gelmon, Karen A

2008-01-01

147

Carbonic Anhydrase IX is Not a Predictor of Outcomes in Non-Metastatic Clear Cell Renal Cell Carcinoma - A Digital Analysis of Tissue Microarray.  

PubMed

Introduction: The knowledge about the molecular biology of clear cell renal cell carcinoma (ccRCC) is evolving, and Carbonic Anhydrase type IX (CA-IX) has emerged as a potential prognostic marker in this challenging disease. However, most of the literature about CA-IX on ccRCC comes from series on metastatic cancer, with a lack of series on non-metastatic cancer. The objective is to evaluate the expression of CA-IX in a cohort of non-metastatic ccRCC, correlating with 1) overall survival, and 2) with established prognostic parameters (T stage, tumor size, Fuhrman nuclear grade, microvascular invasion and peri-renal fat invasion). Materials and Methods: This is a retrospective cohort study. We evaluated 95 patients with non-metastatic clear cell renal cell carcinoma, as to the expression of CA-IX. The analyzed parameters where: overall survival (OS), TNM stage, tumor size (TS), Fuhrman nuclear grade (FNG), microvascular invasion (MVI), peri-renal fat invasion (PFI). We utilized a custom built tissue microarray, and the immunoexpression was digitally quantified using the Photoshop ® software. Results: The mean follow-up time was 7.9 years (range 1.9 to 19.5 years). The analysis of CA-IX expression against the selected prognostic parameters showed no correlation. The results are as follows: Overall survival (p = 0.790); T stage (p = 0.179); tumor size (p = 0.143); grouped Fuhrman nuclear grade (p = 0.598); microvascular invasion (p = 0.685), and peri-renal fat invasion (p = 0.104). Conclusion: Carbonic anhydrase type IX expression does not correlate with overall survival and conventional prognostic parameters in non-metastatic clear cell renal cell carcinoma. PMID:24054396

Zerati, Marcelo; Leite, Kátia R M; Pontes-Junior, José; Segre, Cesar Camara; Reis, Sabrina Thalita; Srougi, Miguel; Dall'oglio, Marcos Francisco

148

Role of Deregulated microRNAs in Breast Cancer Progression Using FFPE Tissue  

PubMed Central

MicroRNAs (miRNAs) contribute to cancer initiation and progression by silencing the expression of their target genes, causing either mRNA molecule degradation or translational inhibition. Intraductal epithelial proliferations of the breast are histologically and clinically classified into normal, atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC). To better understand the progression of ductal breast cancer development, we attempt to identify deregulated miRNAs in this process using Formalin-Fixed, Paraffin-Embedded (FFPE) tissues from breast cancer patients. Following tissue microdissection, we obtained 8 normal, 4 ADH, 6 DCIS and 7 IDC samples, which were subject to RNA isolation and miRNA expression profiling analysis. We found that miR-21, miR-200b/c, miR-141, and miR-183 were consistently up-regulated in ADH, DCIS and IDC compared to normal, while miR-557 was uniquely down-regulated in DCIS. Interestingly, the most significant miRNA deregulations occurred during the transition from normal to ADH. However, the data did not reveal a step-wise miRNA alteration among discrete steps along tumor progression, which is in accordance with previous reports of mRNA profiling of different stages of breast cancer. Furthermore, the expression of MSH2 and SMAD7, two important molecules involving TGF-? pathway, was restored following miR-21 knockdown in both MCF-7 and Hs578T breast cancer cells. In this study, we have not only identified a number of potential candidate miRNAs for breast cancer, but also found that deregulation of miRNA expression during breast tumorigenesis might be an early event since it occurred significantly during normal to ADH transition. Consequently, we have demonstrated the feasibility of miRNA expression profiling analysis using archived FFPE tissues, typically with rich clinical information, as a means of miRNA biomarker discovery.

Chen, Liang; Li, Youhuai; Fu, Yebo; Peng, Jin; Mo, Meng-Hsuan; Stamatakos, Michael; Teal, Christine B.; Brem, Rachel F.; Stojadinovic, Alexander; Grinkemeyer, Michael; McCaffrey, Timothy A.; Man, Yan-gao; Fu, Sidney W.

2013-01-01

149

Integrating Heterogeneous Microarray Data Sources Using Correlation Signatures  

Microsoft Academic Search

Microarrays are one of the latest breakthroughs in experi- mental molecular biology. Thousands of dierent research groups gen- erate tens of thousands of microarray gene expression profiles based on dierent tissues, species, and conditions. Combining such vast amount of microarray data sets is an important and yet challenging problem. In this paper, we introduce a \\

Jaewoo Kang; Jiong Yang; Wanhong Xu; Pankaj Chopra

2005-01-01

150

Hypoxia-Inducible Factors: Mediators of Cancer Progression; Prognostic and Therapeutic Targets in Soft Tissue Sarcomas  

PubMed Central

Soft-tissue sarcomas remain aggressive tumors that result in death in greater than a third of patients due to either loco-regional recurrence or distant metastasis. Surgical resection remains the main choice of treatment for soft tissue sarcomas with pre- and/or post-operational radiation and neoadjuvant chemotherapy employed in more advanced stage disease. However, in recent decades, there has been little progress in the average five-year survival for the majority of patients with high-grade soft tissue sarcomas, highlighting the need for improved targeted therapeutic agents. Clinical and preclinical studies demonstrate that tumor hypoxia and up-regulation of hypoxia-inducible factors (HIFs) is associated with decreased survival, increased metastasis, and resistance to therapy in soft tissue sarcomas. HIF-mediated gene expression regulates many critical aspects of tumor biology, including cell survival, metabolic programming, angiogenesis, metastasis, and therapy resistance. In this review, we discuss HIFs and HIF-mediated genes as potential prognostic markers and therapeutic targets in sarcomas. Many pharmacological agents targeting hypoxia-related pathways are in development that may hold therapeutic potential for treating both primary and metastatic sarcomas that demonstrate increased HIF expression.

Sadri, Navid; Zhang, Paul J.

2013-01-01

151

Characteristic mTOR activity in Hodgkin-lymphomas offers a potential therapeutic target in high risk disease - a combined tissue microarray, in vitro and in vivo study  

PubMed Central

Background Targeting signaling pathways is an attractive approach in many malignancies. The PI3K/Akt/mTOR pathway is activated in a number of human neoplasms, accompanied by lower overall and/or disease free survival. mTOR kinase inhibitors have been introduced in the therapy of renal cell carcinoma and mantle cell lymphoma, and several trials are currently underway. However, the pathological characterization of mTOR activity in lymphomas is still incomplete. Methods mTOR activity and the elements of mTOR complexes were investigated by immunohistochemistry on tissue microarrays representing different human non-Hodgkin-lymphomas (81 cases) and Hodgkin-lymphomas (87 cases). The expression of phospho-mTOR, phospho-4EBP1, phospho-p70S6K, phospho-S6, Rictor, Raptor and Bcl-2, Bcl-xL, Survivin and NF-kappaB-p50 were evaluated, and mTOR activity was statistically analyzed along with 5-year survival data. The in vitro and in vivo effect of the mTOR inhibitor rapamycin was also examined in human Hodgkin-lymphoma cell lines. Results The majority (>50%) of mantle cell lymphoma, Burkitt lymphoma, diffuse large B-cell lymphoma, anaplastic large-cell lymphoma and Hodgkin-lymphoma cases showed higher mTOR activity compared to normal lymphoid tissues. Hodgkin-lymphoma was characterized by high mTOR activity in 93% of the cases, and Bcl-xL and NF-kappaB expression correlated with this mTOR activity. High mTOR activity was observed in the case of both favorable and unfavorable clinical response. Low mTOR activity was accompanied by complete remission and at least 5-year disease free survival in Hodgkin-lymphoma patients. However, statistical analysis did not identify correlation beetween mTOR activity and different clinical data of HL patients, such as survival. We also found that Rictor (mTORC2) was not overexpressed in Hodgkin-lymphoma biopsies and cell lines. Rapamycin inhibited proliferation and induced apoptosis in Hodgkin-lymphoma cells both in vitro and in vivo, moreover, it increased the apoptotic effect of chemotherapeutic agents. Conclusions Targeting mTOR activity may be a potential therapeutic tool in lymphomas. The presence of mTOR activity probably indicates that the inclusion of mTOR inhibition in the therapy of Hodgkin-lymphomas may be feasible and beneficial, especially when standard protocols are ineffective, and it may also allow dose reduction in order to decrease late treatment toxicity. Most likely, the combination of mTOR inhibitors with other agents will offer the highest efficiency for achieving the best clinical response.

2013-01-01

152

Identification of t(17;22)(q22;q13) (COL1A1/PDGFB) in dermatofibrosarcoma protuberans by fluorescence in situ hybridization in paraffin-embedded tissue microarrays.  

PubMed

Dermatofibrosarcoma protuberans is genetically characterized by the translocation t(17;22)(q22;q13) resulting in the PDGFB/COL1A1 fusion gene. Fluorescence in situ hybridization with specific probes enables a rapid detection of this gene. In this study, the presence of the translocation t(17;22)(q22;q13) by fluorescence in situ hybridization in paraffin-embedded tissue microarrays was analyzed. Two tissue microarrays including 40 cases of dermatofibrosarcoma protuberans and 20 dermatofibromas were evaluated. Fluorescence in situ hybridization analyses were performed using a dual-color dual-fusion noncommercial probe. Clinical and histopathologic features were examined, and the association with fluorescence in situ hybridization results was assessed. A total of 29 samples of dermatofibrosarcoma protuberans and 16 of dermatofibromas were successfully evaluated. Twenty-five (86%) dermatofibrosarcoma protuberans samples were positive for the translocation, which was absent in all samples of dermatofibromas. Two of the negative dermatofibrosarcoma protuberans showed unusual, hypercellular areas with marked cytologic atypia, whereas 1 case exhibited overlap features with dermatofibroma. Tumors with fibrosarcomatous areas seemed to have a higher percentage of positive cells and the number of copies of the COL1A1/PDFGB gene. In conclusion, the COL1A1/PDGFB fusion gene was present in most of the dermatofibrosarcoma protuberans tissue samples. The detection of the translocation may be an additional diagnostic tool in cases of dermatofibrosarcoma protuberans showing nonconclusive histologic features. PMID:21111450

Segura, Sonia; Salgado, Rocío; Toll, Agustí; Martín-Ezquerra, Gemma; Yébenes, Mireia; Sáez, Amparo; Solé, Francesc; Barranco, Carlos; Umbert, Pablo; Espinet, Blanca; Pujol, Ramón M

2010-12-15

153

Aptamer Microarrays  

NASA Astrophysics Data System (ADS)

In vitro selection can yield specific, high-affinity aptamers. We and others have devised methods for the automated selection of aptamers and have begun to use these reagents for the construction of arrays. Arrayed aptamers have proven to be almost as sensitive as their solution-phase counterparts and when ganged together can provide both specific and general diagnostic signals for proteins and other ana-lytes. We describe here technical details regarding the production and processing of aptamer microarrays, including blocking, washing, drying, and scanning. We also discuss the challenges involved in developing standardized and reproducible methods for binding and quantitating protein targets. Although signals from fluorescent analytes or sandwiches are typically captured, it has proven possible for immobilized aptamers to be uniquely coupled to amplification methods not available to protein reagents, thus allowing for protein-binding signals to be greatly amplified. Into the future, many of the biosensor methods described in this book can potentially be adapted to array formats, thus further expanding the their utility and applications for aptamer arrays.

Syrett, Heather Angel; Collett, James R.; Ellington, Andrew D.

154

[The mechanism of lung tissue remodeling in the progression of idiopathic pulmonary fibrosis].  

PubMed

The aim of the investigation was to study the specific features of morphological manifestations and the molecular bases of lung tissue remodeling in progressive idiopathic pulmonary fibrosis (IPF). The investigation used open and transbronchial biopsy specimens from 110 patients with IPE/idiopathic pneumonia syndrome in 1997 to 2008. Immunohistochemical analysis was carried out on serial paraffin-embedded lung tissue slices from 20 patients with IPF and 20 control patients. Immunohistochemical staining for the detection of antigens in the paraffin-embedded slices was made using the antibodies to MMP-1, MMP-2, MMP-7, TIMP-4, Apo-CAS, PCNA, PDGF, EGFR, CD34, and SMA. Nonparametric statistical methods were employed. Our findings have indicated that in early-stage IPF, there are proliferating myofibroblasts in the myofibroblastic foci, mainly in the bronchioloalveolar transitional zone (BATZ), which express PCNA and PDGF. Both in early- and late-stage IPF, there were signs of increased readiness of the alveolar and bronchiolar epithelium of BATZ for apoptosis, as judged from Apo-CAS expression. At the same time no Apo-CAS expression was recorded in the myofibroblasts. In the early stage of the disease, the expression of MMP-1, MMP-2, MMP-7, and TIMP-4 in the epitheliocytes, macrophages, fibroblasts, and myofibroblasts was higher than that in the late stage of IPF. At the same time, late-stage IPF was characterized by the higher expression in all lung tissue cells than was early-stage IPF. There was also a significant increase in vessel density in both early and late stages of IPF as compared with intact lung tissue particularly in the BATZ in the control group. Thus, lung tissue remodeling in the progression of IPF from the early to late stage of the disease comprises interrelated processes that are largely localized in the BATZ, such as immune inflammation with pathological reparation, neoangiogenesis, apoptosis, and proliferation of epitheliocytes and myofibroblasts, which lead to the development of interstitial fibrosis and adenomatosis of the lung. PMID:21086635

Kogan, E A; Tyong, F V; Demura, S A

155

Progress of tissue culture and genetic transformation research in pigeon pea [Cajanus cajan (L.) Millsp.].  

PubMed

Pigeon pea [Cajanus cajan (L.) Millsp.] (Family: Fabaceae) is an important legume crop cultivated across 50 countries in Asia, Africa, and the Americas; and ranks fifth in area among pulses after soybean, common bean, peanut, and chickpea. It is consumed as a major source of protein (21%) to the human population in many developing countries. In India, it is the second important food legume contributing to 80% of the global production. Several biotic and abiotic stresses are posing a big threat to its production and productivity. Attempts to address these problems through conventional breeding methods have met with partial success. This paper reviews the chronological progress made in tissue culture through organogenesis and somatic embryogenesis, including the influence of factors such as genotypes, explant sources, and culture media including the supplementation of plant growth regulators. Comprehensive lists of morphogenetic pathways involved in in vitro regeneration through organogenesis and somatic embryogenesis using different explant tissues of diverse pigeon pea genotypes are presented. Similarly, the establishment of protocols for the production of transgenics via particle bombardment and Agrobacterium-mediated transformation using different explant tissues, Agrobacterium strains, Ti plasmids, and plant selectable markers, as well as their interactions on transformation efficiency have been discussed. Future research thrusts on the use of different promoters and stacking of genes for various biotic and abiotic stresses in pigeon pea are suggested. PMID:20652570

Krishna, Gaurav; Reddy, P Sairam; Ramteke, P W; Bhattacharya, P S

2010-07-21

156

Promise and progress in environmental genomics: a status report on the applications of gene expression-based microarray studies in ecologically relevant fish species.  

PubMed

The advent of any new technology is typically met with great excitement. So it was a few years ago, when the combination of advances in sequencing technology and the development of microarray technology made measurements of global gene expression in ecologically relevant species possible. Many of the review papers published around that time promised that these new technologies would revolutionize environmental biology as they had revolutionized medicine and related fields. A few years have passed since these technological advancements have been made, and the use of microarray studies in non-model fish species has been adopted in many laboratories internationally. Has the relatively widespread adoption of this technology really revolutionized the fields of environmental biology, including ecotoxicology, aquaculture and ecology, as promised? Or have these studies merely become a novelty and a potential distraction for scientists addressing environmentally relevant questions? In this review, the promises made in early review papers, in particular about the advances that the use of microarrays would enable, are summarized; these claims are compared to the results of recent studies to determine whether the forecasted changes have materialized. Some applications, as discussed in the paper, have been realized and have led to advances in their field, others are still under development. PMID:21133914

Hook, S E

2010-10-26

157

Macro-Microarray  

NSDL National Science Digital Library

In this activity, learners explore the "nuts and bolts" of gene chips. Learners construct a simple model of a DNA microarray (also known as gene chips) and learn how microarrays can be used to identify and treat disease--including cancer. This resource includes references and an explanation of microarrays.

Yu, Julie

2007-01-01

158

Peripheral Ovine Progressive Pneumonia Provirus Levels Correlate with and Predict Histological Tissue Lesion Severity in Naturally Infected Sheep  

Technology Transfer Automated Retrieval System (TEKTRAN)

Studies were undertaken to determine whether host immune responses in the form of serum anti-ovine progressive pneumonia virus (OPPV) antibody responses or virus replication in the form of peripheral OPP provirus levels associate with the degree of histological tissue lesions in naturally OPPV infec...

159

The effect of donor age on progression of spermatogenesis in canine testicular tissue after xenografting into immunodeficient mice  

Microsoft Academic Search

The objective of this study was to examine the effect of donor age on progression of spermatogenesis in dog (Canis lupus familiaris) testis tissue after xenografting. In Experiment 1, canine testes were obtained by surgical castration. Based on developmental pattern of spermatogenesis at the time of grafting, donors were categorized as immature, young, and adult (6 mo old, respectively). Fragments

M. Abrishami; S. Abbasi; A. Honaramooz

2010-01-01

160

Mucosa-associated lymphoid tissue lymphoma with initial supradiaphragmatic presentation: natural history and patterns of disease progression  

Microsoft Academic Search

Purpose: Mucosa-associated lymphoid tissue (MALT) lymphoma commonly presents in the gastrointestinal (GI) tract. Supradiaphragmatic MALT lymphoma is less common and its natural history is not well defined. This study was conducted to understand the natural history, to determine the frequency of synchronous disease in the GI tract, and to understand the patterns of disease progression after treatment for supradiaphragmatic MALT

Zhongxing Liao; Chul S Ha; Peter McLaughlin; John T Manning; Mark Hess; Fernando Cabanillas; James D Cox

2000-01-01

161

Tissue microarray detection of matrix metalloproteinases, in diseased tricuspid and bicuspid aortic valves with or without pathology of the ascending aorta  

Microsoft Academic Search

Objective: The degeneration of bicuspid aortic valve and its frequent association with ascending aortic pathology, point to a still unidentified genetic tissue defect with unknown mediators. Metalloproteinases (MMPs) are lytic enzymes that have been strongly implicated in aneurysm formation. The purpose of this study was to detect the presence of these enzymes in aortic valvular tissue in healthy and diseased

George J. Koullias; Dimitris P. Korkolis; Pars Ravichandran; Amanda Psyrri; Ioannis Hatzaras; John A. Elefteriades

162

Tissue microarray detection of matrix metalloproteinases, in diseased tricuspid and bicuspid aortic valves with or without pathology of the ascending aorta  

Microsoft Academic Search

Objective: The degeneration of bicuspid aortic valve and its frequent association with ascending aortic pathology, point to a still unidentified genetic tissue defect with unknown mediators. Metalloproteinases (MMPs) are lytic enzymes that have been strongly implicated in aneurysm formation. The purpose of this study was to detect the presence of these enzymes in aortic valvular tissue in healthy and diseased

George J. Koullias; Dimitris P. Korkolis; Pars Ravichandran; Amanda Psyrri; Ioannis Hatzaras; John A. Elefteriades

2004-01-01

163

Microarray technology: basic methodology and application in clinical research for biomarker discovery in vascular diseases.  

PubMed

Microarray technology is a novel tool in molecular biology, capable of quantitating hundreds or thousands of gene transcripts from a given cell or tissue sample simultaneously. A microarray has thousands of DNA fragments or oligonucleotides of known sequence arrayed in a known sequence of rows and columns on a chip. Hybridization of sample RNA that has been reverse-transcribed and labeled enables the detection and quantitation of specific transcripts. The ability to quantitate systemic gene changes in normal vs. diseased states has led to significant progress in many biomedical disciplines, including lipoprotein and atherosclerosis research, and can be used for discovery of diagnostic/prognostic and predictive biomarkers and to test the effectiveness of potential therapeutic agents. The design and analysis of microarray experiments present some unique problems to clinical medicine due to inherent issues related to biological sample procurement and processing, sensitivity and specificity of the assay, reliability and reproducibility of data, and applicability of the technology in multicenter-based clinical studies. This chapter will provide details on the methodologies that address these problems for successful microarray-based transcriptome analysis of tissues, whole blood, cell subpopulations, and cultured cells. PMID:23912982

Raghavachari, Nalini

2013-01-01

164

Gene expression profiling using DNA microarrays.  

PubMed

In Arabidopsis research, microarrays have typically been employed for the measurement of gene expression under different conditions. Microarray analysis is often used to analyze the effects of the expression of wild-type genes (control) versus mutants, the effects of varying environmental conditions, and the effects of hormones. In addition, microarray analysis is used to analyze differences in gene expression between growth stages and tissues. Other array applications include comparative genomic hybridization, chromatin immunoprecipitation, mutation detection, and genotyping. This chapter focuses on gene expression profiling, which is typically performed by the competitive hybridization of two samples, each labeled with a fluorescent dye such as cyanine 3-CTP or cyanine 5-CTP. We describe the steps, from RNA purification to data analysis, that are involved in obtaining data from DNA microarrays. PMID:24057377

Maruyama, Kyonoshin; Yamaguchi-Shinozaki, Kazuko; Shinozaki, Kazuo

2014-01-01

165

Identification of new genes associated with breast cancer progression by gene expression analysis of predefined sets of neoplastic tissues.  

PubMed

Gene expression profiles were studied by microarray analysis in 2 sets of archival breast cancer tissues from patients with distinct clinical outcome. Seventy-seven differentially expressed genes were identified when comparing 30 cases with relapse and 30 cases without relapse within 72 months from surgery. These genes had a specific ontological distribution and some of them have been linked to breast cancer in previous studies: AIB1, the two keratin genes KRT5 and KRT15, RAF1, WIF1 and MSH6. Seven out of 77 differentially expressed genes were selected and analyzed by qRT-PCR in 127 cases of breast cancer. The expression levels of 6 upregulated genes (CKMT1B, DDX21, PRKDC, PTPN1, SLPI, YWHAE) showed a significant association to both disease-free and overall survival. Multivariate analysis using the significant factors (i.e., estrogen receptor and lymph node status) as covariates confirmed the association with survival. There was no correlation between the expression level of these genes and other clinical parameters. In contrast, SERPINA3, the only downregulated gene examined, was not associated with survival, but correlated with steroid receptor status. An indirect validation of our genes was provided by calculating their association with survival in 3 publicly available microarray datasets. CKMT1B expression was an independent prognostic marker in all 3 datasets, whereas other genes confirmed their association with disease-free survival in at least 1 dataset. This work provides a novel set of genes that could be used as independent prognostic markers and potential drug targets for breast cancer. PMID:18561318

Cimino, Daniela; Fuso, Luca; Sfiligoi, Christian; Biglia, Nicoletta; Ponzone, Riccardo; Maggiorotto, Furio; Russo, Giandomenico; Cicatiello, Luigi; Weisz, Alessandro; Taverna, Daniela; Sismondi, Piero; De Bortoli, Michele

2008-09-15

166

Comparison of continuous vs. pulsed focused ultrasound in treated muscle tissue as evaluated by magnetic resonance imaging, histological analysis, and microarray analysis  

Microsoft Academic Search

The purpose of this study was to investigate the effect of different application modes of high intensity focused ultrasound\\u000a (HIFU) to muscle tissue. HIFU was applied to muscle tissue of the flank in C3H\\/Km mice. Two dose regimes were investigated,\\u000a a continuous HIFU and a short-pulsed HIFU mode. Three hours after HIFU treatment pre- and post-contrast T1-weighted, T2-weighted\\u000a images and

Walter Hundt; Esther L. Yuh; Silke Steinbach; Mark D. Bednarski; Samira Guccione

2008-01-01

167

Cluster stability scores for microarray data in cancer studies  

Microsoft Academic Search

Background: A potential benefit of profiling of tissue samples using microarrays is the generation of molecular fingerprints that will define subtypes of disease. Hierarchical clustering has been the primary analytical tool used to define disease subtypes from microarray experiments in cancer settings. Assessing cluster reliability poses a major complication in analyzing output from clustering procedures. While most work has focused

Mark Smolkin; Debashis Ghosh

2003-01-01

168

Gene expression profile analysis of primary glioblastomas and non-neoplastic brain tissue: identification of potential target genes by oligonucleotide microarray and real-time quantitative PCR.  

PubMed

The prognosis of glioblastomas is still extremely poor and the discovery of novel molecular therapeutic targets can be important to optimize treatment strategies. Gene expression analyses comparing normal and neoplastic tissues have been used to identify genes associated with tumorigenesis and potential therapeutic targets. We have used this approach to identify differentially expressed genes between primary glioblastomas and non-neoplastic brain tissues. We selected 20 overexpressed genes related to cell cycle, cellular movement and growth, proliferation and cell-to-cell signaling and analyzed their expression levels by real time quantitative PCR in cDNA obtained from microdissected fresh tumor tissue from 20 patients with primary glioblastomas and from 10 samples of non-neoplastic white matter tissue. The gene expression levels were significantly higher in glioblastomas than in non-neoplastic white matter in 18 out of 20 genes analyzed: P < 0.00001 for CDKN2C, CKS2, EEF1A1, EMP3, PDPN, BNIP2, CA12, CD34, CDC42EP4, PPIE, SNAI2, GDF15 and MMP23b; and NFIA (P: 0.0001), GPS1 (P: 0.0003), LAMA1 (P: 0.002), STIM1 (P: 0.006), and TASP1 (P: 0.01). Five of these genes are located in contiguous loci at 1p31-36 and 2 at 17q24-25 and 8 of them encode surface membrane proteins. PDPN and CD34 protein expression were evaluated by immunohistochemistry and they showed concordance with the PCR results. The present results indicate the presence of 18 overexpressed genes in human primary glioblastomas that may play a significant role in the pathogenesis of these tumors and that deserve further functional investigation as attractive candidates for new therapeutic targets. PMID:18398573

Scrideli, Carlos A; Carlotti, Carlos G; Okamoto, Oswaldo K; Andrade, Vanessa S; Cortez, Maria A A; Motta, Fábio J N; Lucio-Eterovic, Agda K; Neder, Luciano; Rosemberg, Sérgio; Oba-Shinjo, Sueli M; Marie, Suely K N; Tone, Luíz G

2008-04-09

169

Gene expression profile analysis of primary glioblastomas and non-neoplastic brain tissue: identification of potential target genes by oligonucleotide microarray and real-time quantitative PCR  

Microsoft Academic Search

The prognosis of glioblastomas is still extremely poor and the discovery of novel molecular therapeutic targets can be important\\u000a to optimize treatment strategies. Gene expression analyses comparing normal and neoplastic tissues have been used to identify\\u000a genes associated with tumorigenesis and potential therapeutic targets. We have used this approach to identify differentially\\u000a expressed genes between primary glioblastomas and non-neoplastic brain

Carlos A. Scrideli; Carlos G. Carlotti Jr; Oswaldo K. Okamoto; Vanessa S. Andrade; Maria A. A. Cortez; Fábio J. N. Motta; Agda K. Lucio-Eterovic; Luciano Neder; Sérgio Rosemberg; Sueli M. Oba-Shinjo; Suely K. N. Marie; Luíz G. Tone

2008-01-01

170

Microarray analysis of bacterial pathogenicity.  

PubMed

The DNA microarray, a surface that contains an ordered arrangement of each identified open reading frame of a sequenced genome, is the engine of functional genomics. Its output, the expression profile, provides a genome wide snap-shot of the transcriptome. Refined by array-specific statistical instruments and data-mined by clustering algorithms and metabolic pathway databases, the expression profile discloses, at the transcriptional level, how the microbe adapts to new conditions of growth--the regulatory networks that govern the adaptive response and the metabolic and biosynthetic pathways that effect the new phenotype. Adaptation to host microenvironments underlies the capacity of infectious agents to persist in and damage host tissues. While monitoring the whole genome transcriptional response of bacterial pathogens within infected tissues has not been achieved, it is likely that the complex, tissue-specific response is but the sum of individual responses of the bacteria to specific physicochemical features that characterize the host milieu. These are amenable to experimentation in vitro and whole-genome expression studies of this kind have defined the transcriptional response to iron starvation, low oxygen, acid pH, quorum-sensing pheromones and reactive oxygen intermediates. These have disclosed new information about even well-studied processes and provide a portrait of the adapting bacterium as a 'system', rather than the product of a few genes or even a few regulons. Amongst the regulated genes that compose this adaptive system are transcription factors. Expression profiling experiments of transcription factor mutants delineate the corresponding regulatory cascade. The genetic basis for pathogenicity can also be studied by using microarray-based comparative genomics to characterize and quantify the extent of genetic variability within natural populations at the gene level of resolution. Also identified are differences between pathogen and commensal that point to possible virulence determinants or disclose evolutionary history. The host vigorously engages the pathogen; expression studies using host genome microarrays and bacterially infected cell cultures show that the initial host reaction is dominated by the innate immune response. However, within the complex expression profile of the host cell are components mediated by pathogen-specific determinants. In the future, the combined use of bacterial and host microarrays to study the same infected tissue will reveal the dialogue between pathogen and host in a gene-by-gene and site- and time-specific manner. Translating this conversation will not be easy and will probably require a combination of powerful bioinformatic tools and traditional experimental approaches--and considerable effort and time. PMID:12073651

Schoolnik, Gary K

2002-01-01

171

Protein microarrays and novel detection platforms.  

PubMed

The field of proteomics has undergone rapid advancements over the last decade and protein microarrays have emerged as a promising technological platform for the challenging task of studying complex proteomes. This gel-free approach has found an increasing number of applications due to its ability to rapidly and efficiently study thousands of proteins simultaneously. Different protein microarrays, including capture arrays, reverse-phase arrays, tissue microarrays, lectin microarrays and cell-free expression microarrays, have emerged, which have demonstrated numerous applications for proteomics studies including biomarker discovery, protein interaction studies, enzyme-substrate profiling, immunological profiling and vaccine development, among many others. The need to detect extremely low-abundance proteins in complex mixtures has provided motivation for the development of sensitive, real-time and multiplexed detection platforms. Conventional label-based approaches like fluorescence, chemiluminescence and use of radioactive isotopes have witnessed substantial advancements, with techniques like quantum dots, gold nanoparticles, dye-doped nanoparticles and several bead-based methods now being employed for protein microarray studies. In order to overcome the limitations posed by label-based technologies, several label-free approaches like surface plasmon resonance, carbon nanotubes and nanowires, and microcantilevers, among others, have also advanced in recent years, and these methods detect the query molecule itself. The scope of this article is to outline the protein microarray techniques that are currently being used for analytical and function-based proteomics and to provide a detailed analysis of the key technological advances and applications of various detection systems that are commonly used with microarrays. PMID:21329428

Chandra, Harini; Reddy, Panga Jaipal; Srivastava, Sanjeeva

2011-02-01

172

Tissue Engineering Approach to Study the Progression of Breast Tumor Metastasis in Bone.  

National Technical Information Service (NTIS)

Most patients dying of breast cancer suffer painful bone metastasis. It is our hypothesis that the invasive growth and progression of breast metastatic lesions in bone requires the participation of various constituents from 'soil'. A reconstitution of suc...

M. Che D. Nie

2005-01-01

173

Peripheral Ovine Progressive Pneumonia Provirus Levels Correlate with and Predict Histological Tissue Lesion Severity in Naturally Infected Sheep?  

PubMed Central

Studies were undertaken to determine whether anti-ovine progressive pneumonia virus (OPPV) antibody responses in serum or OPP provirus levels in peripheral blood associate with the degree of histologically measured tissue lesions in naturally OPPV-infected sheep. Sections of formalin-fixed, paraffin-embedded, and hematoxylin- and eosin-stained lung, mammary gland, carpal synovial membrane, and brain tissues from 11 OPPV-infected ewes (mean age of 8.6 years) and 5 OPPV-uninfected ewes (mean age of 6 years) were evaluated for lesion severity. Ovine progressive pneumonia (OPP) provirus levels and anti-OPPV antibody titers in peripheral blood and serum samples, respectively, were measured upon euthanasia and 3 years prior to euthanasia. Both mean peripheral OPP provirus levels and mean serum anti-surface envelope glycoprotein (anti-SU) antibody titers at the time of euthanasia were significantly higher in ewes with moderate to severe histological lesions than in ewes with no to mild histological lesions. However, although mean peripheral blood OPP provirus levels at euthanasia and 3 years prior to euthanasia significantly correlated with the highest histological lesion score for any affected tissue (two-tailed P values, 0.03 and 0.02), mean serum anti-SU antibody titers, anti-capsid antibody titers, and anti-transmembrane 90 antibody titers at euthanasia did not show a significant correlation with the highest histological lesion score for any tissue (two-tailed P values, 0.32, 0.97, and 0.18, respectively). These data are the first to show that OPP provirus levels predict and correlate with the extent of OPPV-related histological lesions in various OPPV-affected tissues. These findings suggest that peripheral OPP provirus levels quantitatively contribute more to the development of histological lesions than the systemic anti-SU antibody host immune response.

Herrmann-Hoesing, Lynn M.; Noh, Susan M.; White, Stephen N.; Snekvik, Kevin R.; Truscott, Thomas; Knowles, Donald P.

2009-01-01

174

Peripheral ovine progressive pneumonia provirus levels correlate with and predict histological tissue lesion severity in naturally infected sheep.  

PubMed

Studies were undertaken to determine whether anti-ovine progressive pneumonia virus (OPPV) antibody responses in serum or OPP provirus levels in peripheral blood associate with the degree of histologically measured tissue lesions in naturally OPPV-infected sheep. Sections of formalin-fixed, paraffin-embedded, and hematoxylin- and eosin-stained lung, mammary gland, carpal synovial membrane, and brain tissues from 11 OPPV-infected ewes (mean age of 8.6 years) and 5 OPPV-uninfected ewes (mean age of 6 years) were evaluated for lesion severity. Ovine progressive pneumonia (OPP) provirus levels and anti-OPPV antibody titers in peripheral blood and serum samples, respectively, were measured upon euthanasia and 3 years prior to euthanasia. Both mean peripheral OPP provirus levels and mean serum anti-surface envelope glycoprotein (anti-SU) antibody titers at the time of euthanasia were significantly higher in ewes with moderate to severe histological lesions than in ewes with no to mild histological lesions. However, although mean peripheral blood OPP provirus levels at euthanasia and 3 years prior to euthanasia significantly correlated with the highest histological lesion score for any affected tissue (two-tailed P values, 0.03 and 0.02), mean serum anti-SU antibody titers, anti-capsid antibody titers, and anti-transmembrane 90 antibody titers at euthanasia did not show a significant correlation with the highest histological lesion score for any tissue (two-tailed P values, 0.32, 0.97, and 0.18, respectively). These data are the first to show that OPP provirus levels predict and correlate with the extent of OPPV-related histological lesions in various OPPV-affected tissues. These findings suggest that peripheral OPP provirus levels quantitatively contribute more to the development of histological lesions than the systemic anti-SU antibody host immune response. PMID:19261772

Herrmann-Hoesing, Lynn M; Noh, Susan M; White, Stephen N; Snekvik, Kevin R; Truscott, Thomas; Knowles, Donald P

2009-03-04

175

Expression patterns among interferon regulatory factor-1, human X-box binding protein-1, nuclear factor kappa B, nucleophosmin, estrogen receptor-alpha and progesterone receptor proteins in breast cancer tissue microarrays.  

PubMed

Interferon regulatory factor-1 (IRF-1), human X-box binding protein-1 (hXBP-1), nuclear factor kappa B p65 (NFkappaB p65) and nucleophosmin (NPM) have been implicated in a signaling network of endocrine responsiveness. Expression of these proteins was measured by immunohistochemistry in tissue microarrays of 54 breast tumors. Correlations between each protein and established prognostic markers were assessed by Spearman's rank order correlation coefficient and partial correlation coefficient analyses. Moderate/strong staining is seen for hXBP-1 (79% of tumors) and NFkappaB p65 (57%). NPM exhibits nuclear staining (95%); IRF-1 exhibits both cytosolic (IRF-1c; 90%) and nuclear staining (IRF-1n; 51%). IRF-1c is associated with age (p=0.034); IRF-1n and PgR expression are correlated (p=0.014). NFkappaB p65 shows a borderline association with S phase (p=0.062). Coexpression of IRF-1c and hXBP1 (p=0.001), IRF-1c and NFkappaB (p=0.002), and hXBP-1 and NFkappaB (p=0.018) is observed. An inverse correlation exists between IRF-1n and NFkappaB (p=0.034). All four proteins are detected in breast tumors and their expression patterns support their role(s) in a key signaling network. PMID:16327981

Zhu, Yuelin; Singh, Baljit; Hewitt, Stephen; Liu, Aiyi; Gomez, Bianca; Wang, Antai; Clarke, Robert

2006-01-01

176

Three-dimensional lithographically defined organotypic tissue arrays for quantitative analysis of morphogenesis and neoplastic progression  

PubMed Central

Here, we describe a simple micromolding method to construct three-dimensional arrays of organotypic epithelial tissue structures that approximate in vivo histology. An elastomeric stamp containing an array of posts of defined geometry and spacing is used to mold microscale cavities into the surface of type I collagen gels. Epithelial cells are seeded into the cavities and covered with a second layer of collagen. The cells reorganize into hollow tissues corresponding to the geometry of the cavities. Patterned tissue arrays can be produced in 3–4 h and will undergo morphogenesis over the following 1–3 d. The protocol can easily be adapted to study a variety of tissues and aspects of normal and neoplastic development.

Nelson, Celeste M; Inman, Jamie L; Bissell, Mina J

2010-01-01

177

Progress on materials and scaffold fabrications applied to esophageal tissue engineering.  

PubMed

The mortality rate from esophageal disease like atresia, carcinoma, tracheoesophageal fistula, etc. is increasing rapidly all over the world. Traditional therapies such as surgery, radiotherapy or chemotherapy have been met with very limited success resulting in reduced survival rate and quality of patients' life. Tissue-engineered esophagus, a novel substitute possessing structure and function similar to native tissue, is believed to be an effective therapy and a promising replacement in the future. However, research on esophageal tissue engineering is still at an early stage. Considerable research has been focused on developing ideal scaffolds with optimal materials and methods of fabrication. This article gives a review of materials and scaffold fabrications currently applied in esophageal tissue engineering research. PMID:23498206

Shen, Qiuxiang; Shi, Peina; Gao, Mongna; Yu, Xuechan; Liu, Yuxin; Luo, Ling; Zhu, Yabin

2013-02-04

178

The role of abscisic acid in plant tissue culture: a review of recent progress  

Microsoft Academic Search

Abscisic acid (ABA) plays a significant role in the regulation of many physiological processes of plants. It is often used\\u000a in tissue culture systems to promote somatic embryogenesis and enhance somatic embryo quality by increasing desiccation tolerance\\u000a and preventing precocious germination. ABA is also employed to induce somatic embryos to enter a quiescent state in plant\\u000a tissue culture systems and

Manoj K. Rai; N. S. Shekhawat; Harish; Amit K. Gupta; M. Phulwaria; Kheta Ram; U. Jaiswal

2011-01-01

179

Co-expressed immune and metabolic genes in visceral and subcutaneous adipose tissue from severely obese individuals are associated with plasma HDL and glucose levels: a microarray study  

PubMed Central

Background Excessive accumulation of body fat, in particular in the visceral fat depot, is a major risk factor to develop a variety of diseases such as type 2 diabetes. The mechanisms underlying the increased risk of obese individuals to develop co-morbid diseases are largely unclear. We aimed to identify genes expressed in subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) that are related to blood parameters involved in obesity co-morbidity, such as plasma lipid and glucose levels, and to compare gene expression between the fat depots. Methods Whole-transcriptome SAT and VAT gene expression levels were determined in 75 individuals with a BMI >35 kg/m2. Modules of co-expressed genes likely to be functionally related were identified and correlated with BMI, plasma levels of glucose, insulin, HbA1c, triglycerides, non-esterified fatty acids, ALAT, ASAT, C-reactive protein, and LDL- and HDL cholesterol. Results Of the approximately 70 modules identified in SAT and VAT, three SAT modules were inversely associated with plasma HDL-cholesterol levels, and a fourth module was inversely associated with both plasma glucose and plasma triglyceride levels (p < 5.33 × 10-5). These modules were markedly enriched in immune and metabolic genes. In VAT, one module was associated with both BMI and insulin, and another with plasma glucose (p < 4.64 × 10-5). This module was also enriched in inflammatory genes and showed a marked overlap in gene content with the SAT modules related to HDL. Several genes differentially expressed in SAT and VAT were identified. Conclusions In obese subjects, groups of co-expressed genes were identified that correlated with lipid and glucose metabolism parameters; they were enriched with immune genes. A number of genes were identified of which the expression in SAT correlated with plasma HDL cholesterol, while their expression in VAT correlated with plasma glucose. This underlines both the singular importance of these genes for lipid and glucose metabolism and the specific roles of these two fat depots in this respect.

2010-01-01

180

The BMP signaling gradient patterns dorsoventral tissues in a temporally progressive manner along the anteroposterior axis  

PubMed Central

Summary Patterning of the vertebrate anteroposterior (AP) axis proceeds temporally from anterior to posterior. How dorsoventral (DV) axial patterning relates to AP temporal patterning is unknown. We examined the temporal activity of BMP signaling in patterning ventrolateral cell fates along the AP axis, using transgenes that rapidly turn ‘off’ or ‘on’ BMP signaling. We show that BMP signaling patterns rostral DV cell fates at the onset of gastrulation, while progressively more caudal DV cell fates are patterned at progressively later intervals during gastrulation. Increased BMP signal duration is not required to pattern more caudal DV cell fates, rather distinct temporal intervals of signaling are required. This progressive action is regulated downstream of, or in parallel to BMP signal transduction at the level of Smad1/5 phosphorylation. We propose that a temporal cue regulates a cell's competence to respond to BMP signaling, allowing the acquisition of a cell's DV and AP identity simultaneously.

Tucker, Jennifer A.; Mintzer, Keith A.; Mullins, Mary C.

2008-01-01

181

Fabrication of Glyconanoparticle Microarrays  

PubMed Central

We report a new type of microarray, based on glyconanoparticles (GNPs), to study glycan-lectin interactions. GNPs, synthesized by conjugating carbohydrate ligands on silica nanoparticles, were printed on a photoactive surface followed by covalent immobilization by light activation. The GNP microarrays could be probed by lectins labeled with fluorescein as well as fluorescein-doped silica nanoparticles (FSNPs). Results showed that FSNP as the label enhanced the signals for the higher affinity ligands than the lower ones.

Tong, Qi; Wang, Xin; Wang, Hui; Kubo, Takuya; Yan, Mingdi

2012-01-01

182

Paracrine and Endocrine Effects of Adipose Tissue on Cancer Development and Progression  

PubMed Central

The past few years have provided substantial evidence for the vital role of the local tumor microenvironment for various aspects of tumor progression. With obesity and its pathophysiological sequelae still on the rise, the adipocyte is increasingly moving center stage in the context of tumor stroma-related studies. To date, we have limited insight into how the systemic metabolic changes associated with obesity and the concomitant modification of the paracrine and endocrine panel of stromal adipocyte-derived secretory products (“adipokines”) influence the incidence and progression of obesity-related cancers. Here, we discuss the role of adipocyte dysfunction associated with obesity and its potential impact on cancer biology.

Park, Jiyoung; Euhus, David M.

2011-01-01

183

DNA microarrays in neuropsychopharmacology.  

PubMed

Recent advances in experimental genomics, coupled with the wealth of sequence information available for a variety of organisms, have the potential to transform the way pharmacological research is performed. At present, high-density DNA microarrays allow researchers to quickly and accurately quantify gene-expression changes in a massively parallel manner. Although now well established in other biomedical fields, such as cancer and genetics research, DNA microarrays have only recently begun to make significant inroads into pharmacology. To date, the major focus in this field has been on the general application of DNA microarrays to toxicology and drug discovery and design. This review summarizes the major microarray findings of relevance to neuropsychopharmacology, as a prelude to the design and analysis of future basic and clinical microarray experiments. The ability of DNA microarrays to monitor gene expression simultaneously in a large-scale format is helping to usher in a post-genomic age, where simple constructs about the role of nature versus nurture are being replaced by a functional understanding of gene expression in living organisms. PMID:11479006

Marcotte, E R; Srivastava, L K; Quirion, R

2001-08-01

184

Chromosomal Aberrations in Bladder Cancer: Fresh versus Formalin Fixed Paraffin Embedded Tissue and Targeted FISH versus Wide Microarray-Based CGH Analysis  

PubMed Central

Bladder carcinogenesis is believed to follow two alternative pathways driven by the loss of chromosome 9 and the gain of chromosome 7, albeit other nonrandom copy number alterations (CNAs) were identified. However, confirmation studies are needed since many aspects of this model remain unclear and considerable heterogeneity among cases has emerged. One of the purposes of this study was to evaluate the performance of a targeted test (UroVysion assay) widely used for the detection of Transitional Cell Carcinoma (TCC) of the bladder, in two different types of material derived from the same tumor. We compared the results of UroVysion test performed on Freshly Isolated interphasic Nuclei (FIN) and on Formalin Fixed Paraffin Embedded (FFPE) tissues from 22 TCCs and we didn't find substantial differences. A second goal was to assess the concordance between array-CGH profiles and the targeted chromosomal profiles of UroVysion assay on an additional set of 10 TCCs, in order to evaluate whether UroVysion is an adequately sensitive method for the identification of selected aneuploidies and nonrandom CNAs in TCCs. Our results confirmed the importance of global genomic screening methods, that is array based CGH, to comprehensively determine the genomic profiles of large series of TCCs tumors. However, this technique has yet some limitations, such as not being able to detect low level mosaicism, or not detecting any change in the number of copies for a kind of compensatory effect due to the presence of high cellular heterogeneity. Thus, it is still advisable to use complementary techniques such as array-CGH and FISH, as the former is able to detect alterations at the genome level not excluding any chromosome, but the latter is able to maintain the individual data at the level of single cells, even if it focuses on few genomic regions.

Antolini, Laura; Redaelli, Serena; Valsecchi, Maria Grazia; Bovo, Giorgio; Pallotti, Francesco; Vigano, Paolo; Strada, Guido; Dalpra, Leda; Bentivegna, Angela

2011-01-01

185

The role of tissue transglutaminase (TG2) in regulating the tumour progression of the mouse colon carcinoma CT26  

Microsoft Academic Search

The multifunctional enzyme tissue transglutaminase (TG2) is reported to both mediate and inhibit tumour progression. To elucidate\\u000a these different roles of TG2, we established a series of stable-transfected mouse colon carcinoma CT26 cells expressing a\\u000a catalytically active (wild type) and a transamidating-inactive TG2 (Cys277Ser) mutant. Comparison of the TG2-transfected cells\\u000a with the empty vector control indicated no differences in cell

Panayiotis Kotsakis; Zhuo Wang; Russell John Collighan; Martin Griffin

186

Progress in tissue culture, genetic transformation and applications of biotechnology to trees: an overview  

Microsoft Academic Search

Trees are an integral part of human life, and a vital component of biodiversity. Forest trees in particular are renewable sources of food, fodder, fuel wood, timber and other valuable non-timber products. Due to the rapid growth of population and the human desire to progress, there has been a tremendous reduction in forest cover from the earth’s surface. To maintain

C. C. Giri; B. Shyamkumar; C. Anjaneyulu

2004-01-01

187

Adipose tissue renin-angiotensin-aldosterone system (RAAS) and progression of insulin resistance.  

PubMed

This review focuses on the expression of the key components of the renin-angiotensin-aldosterone axis in fat tissue. At the center of this report is the role of RAAS in normal and excessive fat mass enlargement, the leading etiology of insulin resistance. Understanding the expression and regulation of RAAS components in various fat depots allows insight not only into the processes by which these complex patterns are modified by the enlargement of adipose tissue, but also into their impact on local and systemic response to insulin. PMID:22750719

Marcus, Yonit; Shefer, Gabi; Stern, Naftali

2012-06-29

188

Chromosomal Microarray versus Karyotyping for Prenatal Diagnosis  

PubMed Central

Background Chromosomal microarray analysis has emerged as a primary diagnostic tool for the evaluation of developmental delay and structural malformations in children. We aimed to evaluate the accuracy, efficacy, and incremental yield of chromosomal microarray analysis as compared with karyotyping for routine prenatal diagnosis. Methods Samples from women undergoing prenatal diagnosis at 29 centers were sent to a central karyotyping laboratory. Each sample was split in two; standard karyotyping was performed on one portion and the other was sent to one of four laboratories for chromosomal microarray. Results We enrolled a total of 4406 women. Indications for prenatal diagnosis were advanced maternal age (46.6%), abnormal result on Down’s syndrome screening (18.8%), structural anomalies on ultrasonography (25.2%), and other indications (9.4%). In 4340 (98.8%) of the fetal samples, microarray analysis was successful; 87.9% of samples could be used without tissue culture. Microarray analysis of the 4282 nonmosaic samples identified all the aneuploidies and unbalanced rearrangements identified on karyotyping but did not identify balanced translocations and fetal triploidy. In samples with a normal karyotype, microarray analysis revealed clinically relevant deletions or duplications in 6.0% with a structural anomaly and in 1.7% of those whose indications were advanced maternal age or positive screening results. Conclusions In the context of prenatal diagnostic testing, chromosomal microarray analysis identified additional, clinically significant cytogenetic information as compared with karyotyping and was equally efficacious in identifying aneuploidies and unbalanced rearrangements but did not identify balanced translocations and triploidies. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and others; ClinicalTrials.gov number, NCT01279733.)

Wapner, Ronald J.; Martin, Christa Lese; Levy, Brynn; Ballif, Blake C.; Eng, Christine M.; Zachary, Julia M.; Savage, Melissa; Platt, Lawrence D.; Saltzman, Daniel; Grobman, William A.; Klugman, Susan; Scholl, Thomas; Simpson, Joe Leigh; McCall, Kimberly; Aggarwal, Vimla S.; Bunke, Brian; Nahum, Odelia; Patel, Ankita; Lamb, Allen N.; Thom, Elizabeth A.; Beaudet, Arthur L.; Ledbetter, David H.; Shaffer, Lisa G.; Jackson, Laird

2013-01-01

189

Optimization of oligonucleotide microarray fabricated by spotting 65-mer.  

PubMed

DNA microarrays currently provide measurements of sufficiently high quality to allow a wide variety of sound inferences about gene regulation and the coordination of cellular processes to be drawn. Nonetheless, a desire for greater precision in the measurements continues to drive the microarray research community to seek higher measurement quality through improvements in array fabrication and sample labeling and hybridization. We prepared oligonucleotide microarrays by printing 65-mer on aldehyde functional group-derivatized slides as described in a previous study. We could improve the reliability of data by removing enzymatic bias during probe labeling and hybridizing under a more stringent condition. This optimized method was used to profile gene expression patterns for nine different mouse tissues and organs, and multidimensional scaling (MDS) analysis of data showed both strong similarity between like samples and a clear, highly reproducible separation between different tissue samples. Three other microarrays were fabricated on commercial substrates and hybridized following the manufacturer's instructions. The data were then compared with in-house microarray data and reverse transcription-polymerase chain reaction (RT-PCR) data. The microarray printed on the custom aldehyde slide was superior to microarrays printed on commercially available substrate slides in terms of signal intensities, background, and hybridization characteristics. The data from the custom substrate microarray generally showed good agreement in quantitative changes up to 100-fold changes of transcript abundance with RT-PCR data. However, more accurate comparisons will be made as more genomic sequence information is gathered in the public data domain. PMID:17618862

Lee, Myoyong; Trent, Jeffrey M; Bittner, Michael L

2007-06-08

190

Applications of Functional Protein Microarrays in Basic and Clinical Research  

PubMed Central

The protein microarray technology provides a versatile platform for characterization of hundreds of thousands of proteins in a highly parallel and high-throughput manner. It is viewed as a new tool that overcomes the limitation of DNA microarrays. On the basis of its application, protein microarrays fall into two major classes: analytical and functional protein microarrays. In addition, tissue or cell lysates can also be directly spotted on a slide to form the so-called “reverse-phase” protein microarray. In the last decade, applications of functional protein microarrays in particular have flourished in studying protein function and construction of networks and pathways. In this chapter, we will review the recent advancements in the protein microarray technology, followed by presenting a series of examples to illustrate the power and versatility of protein microarrays in both basic and clinical research. As a powerful technology platform, it would not be surprising if protein microarrays will become one of the leading technologies in proteomic and diagnostic fields in the next decade.

Zhu, Heng; Qian, Jiang

2013-01-01

191

Review paper: Progress in the Field of Conducting Polymers for Tissue Engineering Applications  

Microsoft Academic Search

This review focuses on one of the most exciting applications area of conjugated conducting polymers, which is tissue engineering. Strategies used for the biocompatibility improvement of this class of polymers (including biomolecules’ entrapment or covalent grafting) and also the integrated novel technologies for smart scaffolds generation such as micropatterning, electrospinning, self-assembling are emphasized. These processing alternatives afford the electroconducting polymers

Anca-Dana Bendrea; Luminita Cianga; Ioan Cianga

2011-01-01

192

Protein microarrays: new tools for pharmaceutical development.  

PubMed

Protein microarrays are a relatively new technology, which will dramatically impact the pharmaceutical industry. The critical need for more rapid identification of novel drug targets, and for obtaining high-quality information early in the target validation process is a major driver for the industry. High-throughput protein analytical techniques are critical for obtaining biological information beyond that which transcript analysis can provide, given that proteins are the "worker bees" in cells. The vast complexity of proteins when compared to DNA and RNA in terms of sheer number, and structural and biochemical diversity requires a higher degree of sophistication in both assay design and data analysis. High-throughput microarray technology platforms allow for simultaneous, multi-parametric analysis of complex protein mixtures. Protein microarrays have tremendous potential as a tool for the study of protein-protein, enzyme-substrate, and antibody-antigen interactions among others. They can also be used for biomarkers and drug target identification via comparative proteomic analysis of healthy and disease tissues. More recently, cellular microarrays that enable identification of cell-surface receptors and other cell-surface proteins allowing rapid screening of cell-specific, novel drug targets, are being developed. This review will focus on the technical issues and potential applications of protein microarrays in pharmaceutical discovery. PMID:12851736

Kumble, K D

2003-07-08

193

Multiple deletions of mitochondrial DNA in several tissues of a patient with severe retarded depression and familial progressive external ophthalmoplegia.  

PubMed Central

Multiple deletions of mitochondrial DNA (mtDNA) have recently been reported in familial progressive external ophthalmoplegia (PEO), in a case of progressive encephalomyopathy, and in inherited recurrent myoglobinuria. The inheritance of familial PEO has been autosomal dominant, which indicates that a mutation in an unknown nuclear gene results in several mtDNA deletions of different sizes in these patients. We report a patient with autosomal dominant PEO, whose major clinical symptom, however, was severe retarded depression. The morphological analyses of the tissue samples derived from autopsy showed various abnormalities in the mitochondria in all the tissues studied. The activities of the respiratory chain enzymes encoded by mtDNA were remarkably reduced in the skeletal muscle. The mtDNA analyses confirmed that besides myopathy, this patient had a multisystem disorder with widespread distribution of multiple deletions of mtDNA. The highest percentage of mutated mtDNA was found in the brain, skeletal muscle and the heart, the relative quantity of mutated mtDNA correlating to the severity of the clinical symptoms. Images

Suomalainen, A; Majander, A; Haltia, M; Somer, H; Lonnqvist, J; Savontaus, M L; Peltonen, L

1992-01-01

194

LDRD Progress Report: Radioimmunotherapy using oxide nanoparticles: Radionuclide contaiment and mitigation of normal tissue toxicity.  

SciTech Connect

Radionuclides with specific emission properties can be incorporated into metal-chalcogenide and metal-oxide nanoparticles. Coupled to antibodies, these conjugates could be injected into the bloodstream to target and destroy non-solid tumors or target organs for radioimaging. In the first year of this project, two types of radioactive nanoparticles, CdTe: {sup 125m}Te and Y{sub 2}O{sub 3}: {sup 170}Tm were synthesized and coupled to antibodies specific to murine epithelial lung tissue. The nanoparticles successfully target the lung tissue in vivo. Some leaching of the radioisotope was observed. The coming year will explore other types of nanoparticles (other crystal chemistries) in order to minimize leaching.

Rondinone, Adam Justin [ORNL; Dai, Sheng [ORNL; Mirzadeh, Saed [ORNL; Kennel, Steve J [ORNL

2005-10-01

195

Designing Microarray Experiments  

NASA Astrophysics Data System (ADS)

Gene expression microarrays have become an important exploratory tool in many screening experiments that aim to discover the genes that change expression in two or more biological conditions and can be used to build molecular profiles for both diagnostic and prognostic use. The still very high costs of microarrays and the difficulty in generating the biological samples are critical issues of microarraybased screening experiments, and the experimental design plays a crucial role in how informative an experiment is going to be. In this chapter, we describe some of the major issues related to the design of either randomized control trials or observational studies and discuss the choice of powerful sample sizes, the selection of informative experimental conditions, and experimental strategies that can minimize confounding. We conclude with a discussion of some of the open problems in the design and analysis of microarray experiments that need further research.

Sebastiani, Paola; Milton, Jacqui; Wang, Ling

196

Magnetic Analysis of Post-mortem Hippocampal Tissue from Alzheimer's Patients: Changes with Progression of the Disease.  

NASA Astrophysics Data System (ADS)

Increases of iron in the human brain with age have been observed and may be accompanied by the development of neurodegenerative diseases, such as Alzheimer's. We have measured the magnetic characteristics of several sets of slides of hippocampal tissue from deceased Alzheimer patients. The slides were made available by the Harvard Brain Bank. The pathology of the tissue was classified in the Braak stages I to VI used to describe the progression of the disease. In general, the slides from patients with higher Braak stages and development of fibrillary tangles and plaques had greater magnetic moments than did those with Braak stage II. However, the peak values were at stage IV and V. To mitigate errors due to the inevitable differences in masses of the tissue on individual slides and their precise location in the hippocampus, ratios of magnetic properties were also observed. Ratios of Anhysteretic Remanent Magnetizaton (ARM) to Isothermal Remanent Magnetization (IRM) were obtained and showed a decrease from Stage II to the more advanced stages, with the minimum values at stages IV and V. The acquisition and demagnetization of IRM are consistent with the presence of magnetite, but also indicate a magnetically harder phase.

Fuller, M.; Zinin, P.; Favia, J.; Tatsumi, L.; Kletetschka, G.; Adachi, T.

2007-12-01

197

Progress in the tissue engineering and stem cell industry "are we there yet?".  

PubMed

This report presents a detailed update to our 2008 publication on the tissue engineering (TE) and stem cell industry. Data are reported through mid 2011 showing an almost three-fold growth in commercial sales over the past 4 years. In addition, the number of companies selling products or offering services has increased over two-fold to 106, and they are generating a remarkable $3.5 billion in sales. Overall, the TE and stem cell sector is spending $3.6 billion and employing almost 14,000 employees. These data suggest the TE and stem cell industry has stabilized and is on a path pointing toward continued success. PMID:22220809

Jaklenec, Ana; Stamp, Andrea; Deweerd, Elizabeth; Sherwin, Angela; Langer, Robert

2012-02-08

198

Recent progresses in understanding of water interacting with biomolecules, and inside living cells and tissues  

NASA Astrophysics Data System (ADS)

Recent inelastic and quasi-elastic neutron scattering measurements of water in cell preparations has provided information on the interfacial (or bound) water molecules. The experiments show that the interfacial water molecules can be readily distinguished from those in the bulk (bulk water), especially using inelastic neutron scattering data over the 20-130 meV range. Studies of intact biological systems - whole cells and tissues - demonstrated the feasibility of using these methods to assess the degree of interfacial water and their potential for monitoring physiological changes. Here we also describe the effect of heat shock and osmotic stress on yeast and E. coli cells, and show that the interfacial water content increases with elevated osmolarity and heat shock, and decreases under hypoosmotic conditions.

Ford, R. C.; Li, J.

199

Neutron interactions with biological tissue. Progress report, December 1, 1993--November 30, 1994  

SciTech Connect

An attempt is made to obtain information about the physical stage of neutron interactions with tissue through secondary charged particles. The authors use theoretical calculations whose input includes neutron cross section data; range, stopping power, ion yield, and straggling information; and geometrical properties. Outputs are initial and slowing-down spectra of charged particles, kerma factors, average values of quality factors, microdosimetric spectra, and integral microdosimetric parameters such as {bar y}{sub F}, {bar y}{sub D}, y{sup *}. Since it has become apparent that nanometer site sizes are more relevant to radiobiological effects, the calculations of event size spectra and their parameters have been extended to these smaller diameters. This information is basic to radiological physics, radiation biology, radiation protection of workers, and standards for neutron dose measurement.

NONE

1994-12-31

200

High levels of carbonic anhydrase IX in tumour tissue and plasma are biomarkers of poor prognostic in patients with non-small cell lung cancer  

Microsoft Academic Search

Background:Carbonic anhydrase IX (CAIX) is an enzyme upregulated by hypoxia during tumour development and progression. This study was conducted to assess if the expression of CAIX in tumour tissue and\\/or plasma can be a prognostic factor in patients with non-small cell lung cancer (NSCLC).Methods:Tissue microarrays containing 555 NSCLC tissue samples were generated for quantification of CAIX expression. The plasma level

M ?lie; N M Mazure; V Hofman; R E Ammadi; C Ortholan; C Bonnetaud; K Havet; N Venissac; B Mograbi; J Mouroux; J Pouysségur; P Hofman

2010-01-01

201

In vivo monitoring of Yersinia ruckeri in fish tissues: progression and virulence gene expression.  

PubMed

In this study, the utilization of bioluminescence imaging (BLI) allowed us to define the progression of Yersinia ruckeri during the infection of rainbow trout. A luminescent Y.?ruckeri 150 strain was engineered using the pCS26-Pac plasmid containing the lux operon from Photorhabdus luminescens. Two different models of infection of rainbow trout were defined depending on the route in which bacteria were administered, being the gut the major organ affected following bath immersion. This indicates that this organ is important for bacterial dissemination inside the fish and the establishment of the infection. Moreover, the expression of three previously selected operons by in vivo expression technology (IVET) was analysed, the yhlBA involved in the production of a haemolysin, the cdsAB related to the uptake of cysteine and the yctCBA implicated in citrate uptake. Apart from these factors, the expression of yrp1 encoding a serralysin metalloprotease involved in pathogenesis was also analysed. The results indicated that all of the assayed promoters were expressed during infection of rainbow trout. In addition to these findings, the methodology described in this work constitutes a useful model for studying the infection process in other fish pathogenic bacteria. PMID:23757147

Méndez, J; Guijarro, J A

2013-01-15

202

Effects of BRAF inhibitors on human melanoma tissue before treatment, early during treatment, and on progression.  

PubMed

Selective BRAF inhibitors (BRAFi) are a standard of care for the treatment of BRAF(V) (600) -mutant metastatic melanoma. We analyzed a unique set of serial triplicate human metastatic melanoma tumor biopsies to identify biomarkers of BRAFi response and resistance. Morphologic features and immunohistochemical biomarkers were analyzed in 37 metastatic melanoma biopsies at pretreatment (PRE), early during treatment (EDT), and on progression (PROG) from 15 patients treated with a BRAFi and correlated with response and outcome. At EDT, proliferative markers decreased regardless of response, whereas markers of cell death increased in responders. High expression of nuclear p27 at baseline was the strongest predictor of a poorer OS and predicted worse response. The results show that BRAFi are universally antiproliferative, regardless of clinical response, whereas markers of cell death increased only in responders. The addition of therapies targeting the cell cycle machinery may improve the response and duration of BRAFi, and investigation of the mechanisms of apoptosis may provide additional therapeutic targets. PMID:23557327

Long, Georgina V; Wilmott, James S; Haydu, Lauren E; Tembe, Varsha; Sharma, Raghwa; Rizos, Helen; Thompson, John F; Howle, Julie; Scolyer, Richard A; Kefford, Richard F

2013-05-03

203

Tissue Inhibitor of Metalloproteinase-4 Is Elevated in Early-Stage Breast Cancers with Accelerated Progression and Poor Clinical Course  

PubMed Central

An increasing number of breast cancer patients are diagnosed with small, localized, early-stage tumors. These patients are typically thought to have a good prognosis for long-term disease-free survival, but epidemiological studies indicate that up to 30% may have a recurrence within 3 to 5 years of diagnosis. Identifying patients with a high risk of recurrence and/or progression is important because they could be more aggressively treated at diagnosis to improve their chances for disease-free survival. Recent evidence suggests that elevated levels of the matrix metalloproteinase inhibitor, tissue inhibitor of metalloproteinase (TIMP)-4, are associated with malignant progression of ductal carcinoma in situ, a precancerous lesion. To examine the association of TIMP-4 with survival outcomes, we conducted a retrospective immunohistochemical analysis of 314 cases from patients with early-stage disease, defined as tumors smaller than 2 cm and no spread to lymph nodes (tumor-node-metastasis staging: T1N0MX). We found that tumors with elevated levels of TIMP-4 were correlated with a reduced probability of long-term disease-free survival, especially in patients with estrogen receptor-negative tumors. Our findings prompt further evaluation of TIMP-4 as a simple prognostic marker that may help identify patients with early-stage breast cancer who could benefit from more aggressive treatment at diagnosis.

Liss, Michaelann; Sreedhar, Nandhini; Keshgegian, Albert; Sauter, Guido; Chernick, Michael R.; Prendergast, George C.; Wallon, U. Margaretha

2009-01-01

204

Tissue inhibitor of metalloproteinase-4 is elevated in early-stage breast cancers with accelerated progression and poor clinical course.  

PubMed

An increasing number of breast cancer patients are diagnosed with small, localized, early-stage tumors. These patients are typically thought to have a good prognosis for long-term disease-free survival, but epidemiological studies indicate that up to 30% may have a recurrence within 3 to 5 years of diagnosis. Identifying patients with a high risk of recurrence and/or progression is important because they could be more aggressively treated at diagnosis to improve their chances for disease-free survival. Recent evidence suggests that elevated levels of the matrix metalloproteinase inhibitor, tissue inhibitor of metalloproteinase (TIMP)-4, are associated with malignant progression of ductal carcinoma in situ, a precancerous lesion. To examine the association of TIMP-4 with survival outcomes, we conducted a retrospective immunohistochemical analysis of 314 cases from patients with early-stage disease, defined as tumors smaller than 2 cm and no spread to lymph nodes (tumor-node-metastasis staging: T1N0MX). We found that tumors with elevated levels of TIMP-4 were correlated with a reduced probability of long-term disease-free survival, especially in patients with estrogen receptor-negative tumors. Our findings prompt further evaluation of TIMP-4 as a simple prognostic marker that may help identify patients with early-stage breast cancer who could benefit from more aggressive treatment at diagnosis. PMID:19700750

Liss, Michaelann; Sreedhar, Nandhini; Keshgegian, Albert; Sauter, Guido; Chernick, Michael R; Prendergast, George C; Wallon, U Margaretha

2009-08-21

205

Microarray Data Feature Selection Using Hybrid GA-IBPSO  

Microsoft Academic Search

DNA microarray examples are generated by a hybridization of mRNA from sample tissues or blood to cDNA (in the case of a spotted\\u000a array), or hybridization of oligonucleotide of DNA (in the case of Affymetrix chips, on the surface of a chiparray). DNA microarray\\u000a technology allows for the simultaneous monitoring and measurement of thousands of gene expression activation levels in

Cheng-San Yang; Li-Yeh Chuang; Chang-Hsuan Ho; Cheng-Hong Yang

206

Tissue transglutaminase as a central mediator in inflammation-induced progression of breast cancer.  

PubMed

TGM2 is a stress-responsive gene that encodes a multifunctional and structurally complex protein called tissue transglutaminase (abbreviated as TG2 or tTG). TGM2 expression is frequently upregulated during inflammation and wounding. Emerging evidence indicates that TGM2 expression is aberrantly upregulated in multiple cancer cell types, particularly those selected for resistance to chemotherapy and radiation therapy and those isolated from metastatic sites. It is becoming increasingly evident that chronic expression of TG2 in epithelial cancer cells initiates a complex series of signaling networks which contributes to the development of drug resistance and an invasive phenotype. For example, forced or basal high expression of TG2 in mammary epithelial cells is associated with activation of nuclear transcription factor-kappa B (NF-?B), Akt, focal adhesion kinase, and hypoxia-inducible factor. All of these changes are considered hallmarks of aggressive tumors. TG2 expression is able to induce the developmentally regulated program of epithelial-to-mesenchymal transition (EMT) and to confer cancer stem cell (CSC) traits in mammary epithelial cells; both EMT and CSCs have been implicated in cancer metastasis and resistance to standard therapies. Importantly, TG2 expression in tumor samples is associated with poor disease outcome, increased drug resistance, and increased incidence of metastasis. These observations imply that TG2 plays a crucial role in promoting an aggressive phenotype in mammary epithelial cells. In this review, we discuss recent evidence that TG2-regulated pathways contribute to the aggressive phenotype in breast cancer. PMID:23673317

Agnihotri, Navneet; Kumar, Santosh; Mehta, Kapil

2013-02-25

207

Creation of a digital slide and tissue microarray resource from a multi-institutional predictive toxicology study in the rat: an initial report from the PredTox group.  

PubMed

The widespread use of digital slides has only recently come to the fore with the development of high-throughput scanners and high performance viewing software. This development, along with the optimisation of compression standards and image transfer techniques, has allowed the technology to be used in wide reaching applications including integration of images into hospital information systems and histopathological training, as well as the development of automated image analysis algorithms for prediction of histological aberrations and quantification of immunohistochemical stains. Here, the use of this technology in the creation of a comprehensive library of images of preclinical toxicological relevance is demonstrated. The images, acquired using the Aperio ScanScope CS and XT slide acquisition systems, form part of the ongoing EU FP6 Integrated Project, Innovative Medicines for Europe (InnoMed). In more detail, PredTox (abbreviation for Predictive Toxicology) is a subproject of InnoMed and comprises a consortium of 15 industrial (13 large pharma, 1 technology provider and 1 SME) and three academic partners. The primary aim of this consortium is to assess the value of combining data generated from 'omics technologies (proteomics, transcriptomics, metabolomics) with the results from more conventional toxicology methods, to facilitate further informed decision making in preclinical safety evaluation. A library of 1709 scanned images was created of full-face sections of liver and kidney tissue specimens from male Wistar rats treated with 16 proprietary and reference compounds of known toxicity; additional biological materials from these treated animals were separately used to create 'omics data, that will ultimately be used to populate an integrated toxicological database. In respect to assessment of the digital slides, a web-enabled digital slide management system, Digital SlideServer (DSS), was employed to enable integration of the digital slide content into the 'omics database and to facilitate remote viewing by pathologists connected with the project. DSS also facilitated manual annotation of digital slides by the pathologists, specifically in relation to marking particular lesions of interest. Tissue microarrays (TMAs) were constructed from the specimens for the purpose of creating a repository of tissue from animals used in the study with a view to later-stage biomarker assessment. As the PredTox consortium itself aims to identify new biomarkers of toxicity, these TMAs will be a valuable means of validation. In summary, a large repository of histological images was created enabling the subsequent pathological analysis of samples through remote viewing and, along with the utilisation of TMA technology, will allow the validation of biomarkers identified by the PredTox consortium. The population of the PredTox database with these digitised images represents the creation of the first toxicological database integrating 'omics and preclinical data with histological images. PMID:18479893

Mulrane, Laoighse; Rexhepaj, Elton; Smart, Valerie; Callanan, John J; Orhan, Diclehan; Eldem, Türkan; Mally, Angela; Schroeder, Susanne; Meyer, Kirstin; Wendt, Maria; O'Shea, Donal; Gallagher, William M

2008-05-13

208

A method to improve selection of molecular targets by circumventing the ADME pharmacokinetic system utilizing PharmArray DNA microarrays  

Microsoft Academic Search

DNA microarrays may be used to identify potential molecular targets for drug discovery. Yet, DNA microarray experiments provide massive amounts of data. To limit the choice of potential molecular targets, it may be desirable to eliminate genes coincidentally up-regulated in tissues implicated in absorption, distribution, metabolism, and excretion (ADME) pharmacokinetics. DNA microarray experiments were performed to demonstrate a gene-exclusion approach

Thomas P Dooley; Ernest V Curto; Shanker P Reddy; Richard L Davis; Glenna Lambert; Teresa W Wilborn

2003-01-01

209

Statistical issues in signal extraction from microarrays  

NASA Astrophysics Data System (ADS)

Microarray technologies are increasingly used in biomedical research to study genome-wide expression profiles in the post genomic era. Their popularity is largely due to their high throughput and economical affordability. For example, microarrays have been applied to studies of cell cycle, regulatory circuitry, cancer cell lines, tumor tissues, and drug discoveries. One obstacle facing the continued success of applying microarray technologies, however, is the random variaton present on microarrays: within signal spots, between spots and among chips. In addition, signals extracted by available software packages seem to vary significantly. Despite a variety of software packages, it appears that there are two major approaches to signal extraction. One approach is to focus on the identification of signal regions and hence estimation of signal levels above background levels. The other approach is to use the distribution of intensity values as a way of identifying relevant signals. Building upon both approaches, the objective of our work is to develop a method that is statistically rigorous and also efficient and robust. Statistical issues to be considered here include: (1) how to refine grid alignment so that the overall variation is minimized, (2) how to estimate the signal levels relative to the local background levels as well as the variance of this estimate, and (3) how to integrate red and green channel signals so that the ratio of interest is stable, simultaneously relaxing distributional assumptions.

Bergemann, Tracy; Quiaoit, Filemon; Delrow, Jeffrey J.; Zhao, Lue Ping

2001-06-01

210

Membrane-based microarrays  

NASA Astrophysics Data System (ADS)

Microarrays represent a new approach to the rapid detection and identification of analytes. Studies to date have shown that the immobilization of receptor molecules (such as DNA, oligonucleotides, antibodies, enzymes and binding proteins) onto silicon and polymeric substrates can result in arrays able to detect hundreds of analytes in a single step. The formation of the receptor/analyte complex can, itself, lead to detection, or the complex can be interrogated through the use of fluorescent, chemiluminescent or radioactive probes and ligands.

Dawson, Elliott P.; Hudson, James; Steward, John; Donnell, Philip A.; Chan, Wing W.; Taylor, Richard F.

1999-11-01

211

Quantifiable fluorescent glycan microarrays  

Microsoft Academic Search

A glycan microarray was developed by using 2,6-diaminopyridine (DAP) as a fluorescent linker and printing of the glycan-DAP\\u000a conjugates (GDAPs) on epoxy-activated glass slides. Importantly, all coupled GDAPs showed a detectable level of concentration-dependent\\u000a GDAP fluorescence under blue laser excitation (495 nm) that can be used for both grid location and on-slide quantification.\\u000a A glycan array including a large number of

Xuezheng Song; Baoyun Xia; Yi Lasanajak; David F. Smith; Richard D. Cummings

2008-01-01

212

Tissue prostate specific antigen (PSA) facilitates refractory prostate tumor progression via enhancing ARA70-regulated androgen receptor transactivation  

PubMed Central

Despite being well recognized as the best biomarker for prostate cancer, pathophysiological roles of prostate-specific antigen (PSA) remain unclear. We report here that tissue PSA may be involved in the hormone-refractory prostate cancer progression. Histological analyses show the increased tissue PSA levels are correlated with lower cell apoptosis index and higher cell proliferation rate in hormone-refractory tumors specimens. By stably transfecting PSA-cDNA into various prostate cancer cell lines, we found PSA could promote the growth of AR-positive CWR22rv1 and high passage LNCaP (hormone refractory prostate cancer cells), but not that of AR-negative PC-3 and Du145 cells. Surprisingly, PSA’s protease activity is not crucial for PSA to stimulate growth and promote AR transactivaton. We further showed that increased PSA could enhance ARA70-induced AR transactivation via modulating p53 pathway that result in the decreased apoptosis and increased cell proliferation in prostate cancer cells. Knockdown of PSA in LNCaP and CWR22rv1 cells causes cell apoptosis and cell growth arrest at the G1 phase. In vitro colony formation assay and in vivo xenografted tumors results showed the suppression of prostate cancer growth via targeting PSA expression. Collectively, our findings suggest that in addition to be biomarker, PSA may also become a new potential therapeutic target for prostate cancer. PSA-siRNA or smaller molecules that can degrade PSA protein may be developed as alternative approaches to treat the prostate cancer.

Niu, Yuanjie; Yeh, Shuyuan; Miyamoto, Hiroshi; Li, Gonghui; Altuwaijri, Saleh; Yuan, Jianqun; Han, Ruifa; Ma, Tengxiang; Kuo, Hann-Chorng; Chang, Chawnshang

2008-01-01

213

Identification of Tumor-associated Autoantigens for the Diagnosis of Colorectal Cancer in Serum Using High Density Protein Microarrays*  

PubMed Central

There is a mounting evidence of the existence of autoantibodies associated to cancer progression. Antibodies are the target of choice for serum screening because of their stability and suitability for sensitive immunoassays. By using commercial protein microarrays containing 8000 human proteins, we examined 20 sera from colorectal cancer (CRC) patients and healthy subjects to identify autoantibody patterns and associated antigens. Forty-three proteins were differentially recognized by tumoral and reference sera (p value <0.04) in the protein microarrays. Five immunoreactive antigens, PIM1, MAPKAPK3, STK4, SRC, and FGFR4, showed the highest prevalence in cancer samples, whereas ACVR2B was more abundant in normal sera. Three of them, PIM1, MAPKAPK3, and ACVR2B, were used for further validation. A significant increase in the expression level of these antigens on CRC cell lines and colonic mucosa was confirmed by immunoblotting and immunohistochemistry on tissue microarrays. A diagnostic ELISA based on the combination of MAPKAPK3 and ACVR2B proteins yielded specificity and sensitivity values of 73.9 and 83.3% (area under the curve, 0.85), respectively, for CRC discrimination after using an independent sample set containing 94 sera representative of different stages of progression and control subjects. In summary, these studies confirmed the presence of specific autoantibodies for CRC and revealed new individual markers of disease (PIM1, MAPKAPK3, and ACVR2B) with the potential to diagnose CRC with higher specificity and sensitivity than previously reported serum biomarkers.

Babel, Ingrid; Barderas, Rodrigo; Diaz-Uriarte, Ramon; Martinez-Torrecuadrada, Jorge Luis; Sanchez-Carbayo, Marta; Casal, J. Ignacio

2009-01-01

214

The role of tissue transglutaminase (TG2) in regulating the tumour progression of the mouse colon carcinoma CT26.  

PubMed

The multifunctional enzyme tissue transglutaminase (TG2) is reported to both mediate and inhibit tumour progression. To elucidate these different roles of TG2, we established a series of stable-transfected mouse colon carcinoma CT26 cells expressing a catalytically active (wild type) and a transamidating-inactive TG2 (Cys277Ser) mutant. Comparison of the TG2-transfected cells with the empty vector control indicated no differences in cell proliferation, apoptosis and susceptibility to doxorubicin, which correlated with no detectable changes in the activation of the transcription factor NF-?B. TG2-transfected cells showed increased expression of integrin ?3, and were more adherent and less migratory on fibronectin than control cells. Direct interaction of TG2 with ?3 integrins was demonstrated by immunoprecipitation, suggesting that TG2 acts as a coreceptor for fibronectin with ?3 integrins. All cells expressed the same level of TGF? receptors I and II, but only cells transfected with active TG2 had increased levels of TGF?1 and matrix-deposited fibronectin, which could be inhibited by TG2 site-directed inhibitors. Moreover, only cells transfected with active TG2 were capable of inhibiting tumour growth when compared to the empty vector controls. We conclude that in this colon carcinoma model increased levels of active TG2 are unfavourable to tumour growth due to their role in activation of TGF?1 and increased matrix deposition, which in turn favours increased cell adhesion and a lowered migratory and invasive behaviour. PMID:21046178

Kotsakis, Panayiotis; Wang, Zhuo; Collighan, Russell John; Griffin, Martin

2010-11-03

215

Microarray databases: standards and ontologies.  

PubMed

A single microarray can provide information on the expression of tens of thousands of genes. The amount of information generated by a microarray-based experiment is sufficiently large that no single study can be expected to mine each nugget of scientific information. As a consequence, the scale and complexity of microarray experiments require that computer software programs do much of the data processing, storage, visualization, analysis and transfer. The adoption of common standards and ontologies for the management and sharing of microarray data is essential and will provide immediate benefit to the research community. PMID:12454640

Stoeckert, Christian J; Causton, Helen C; Ball, Catherine A

2002-12-01

216

DNA microarray application in ecotoxicology: experimental design, microarray scanning, and factors affecting transcriptional profiles in a small fish species.  

PubMed

The research presented here is part of a larger study of the molecular mode of action of endocrine-disrupting chemicals targeting the hypothalamic-pituitary-gonadal axis in zebrafish (Danio rerio). It addresses several issues critical to microarray application in aquatic ecotoxicology: experimental design, microarray scanning, gene expression intensity distribution, and the effect of experimental parameters on the zebrafish transcriptome. Expression profiles from various tissues of individual zebrafish exposed to 17alpha-ethinylestradiol (30 ng/L), fadrozole (25 micro.g/L), or 17beta-trenbolone (3.0 microg/L) for 48 or 96 h were examined with the Agilent Oligo Microarray (G2518A). As a flexible and efficient alternative to the designs commonly used in microarray studies, an unbalanced incomplete block design was found to be well suited for this work, as evidenced by high data reproducibility, low microarray-to-microarray variability, and little gene-specific dye bias. Random scanner noise had little effect on data reproducibility. A low-level, slightly variable Cyanine 3 (Cy3) contaminant was revealed by hyperspectral imaging, suggesting fluorescence contamination as a potential contributor to the large variance associated with weakly expressed genes. Expression intensities of zebrafish genes were skewed toward the lower end of their distribution range, and more weakly expressed genes tended to have larger variances. Tissue type, followed in descending order by gender, chemical treatment, and exposure duration, had the greatest effect on the overall gene expression profiles, a finding potentially critical to experimental design optimization. Overall, congruence was excellent between quantitative polymerase chain reaction results and microarray profiles of 13 genes examined across a subset of 20 pairs of ovarian samples. These findings will help to improve applications of microarrays in future ecotoxicological studies. PMID:17990945

Wang, Rong-Lin; Biales, Adam; Bencic, David; Lattier, David; Kostich, Mitch; Villeneuve, Dan; Ankley, Gerald T; Lazorchak, Jim; Toth, Greg

2008-03-01

217

VAMPIRE microarray suite: a web-based platform for the interpretation of gene expression data  

Microsoft Academic Search

Microarrays are invaluable high-throughput tools used to snapshot the gene expression profiles of cells and tissues. Among the most basic and funda- mental questions asked of microarray data is whe- ther individual genes are significantly activated or repressed by a particular stimulus. We have previ- ously presented two Bayesian statistical methods for this level of analysis, collectively known as variance-modeled

Albert Hsiao; Trey Ideker; Jerrold M. Olefsky; Shankar Subramaniam

2005-01-01

218

Boolean implication networks derived from large scale, whole genome microarray datasets  

Microsoft Academic Search

We describe a method for extracting Boolean implications (if-then relationships) in very large amounts of gene expression microarray data. A meta-analysis of data from thousands of microarrays for humans, mice, and fruit flies finds millions of implication relationships between genes that would be missed by other methods. These relationships capture gender differences, tissue differences, development, and differentiation. New relationships are

Debashis Sahoo; David L Dill; Andrew J Gentles; Robert Tibshirani; Sylvia K Plevritis

2008-01-01

219

High quality protein microarray using in situ protein purification  

Microsoft Academic Search

BACKGROUND: In the postgenomic era, high throughput protein expression and protein microarray technologies have progressed markedly permitting screening of therapeutic reagents and discovery of novel protein functions. Hexa-histidine is one of the most commonly used fusion tags for protein expression due to its small size and convenient purification via immobilized metal ion affinity chromatography (IMAC). This purification process has been

Keehwan Kwon; Carissa Grose; Rembert Pieper; Gagan A Pandya; Robert D Fleischmann; Scott N Peterson

2009-01-01

220

Basic Concepts of Microarrays and Potential Applications in Clinical Microbiology  

PubMed Central

Summary: The introduction of in vitro nucleic acid amplification techniques, led by real-time PCR, into the clinical microbiology laboratory has transformed the laboratory detection of viruses and select bacterial pathogens. However, the progression of the molecular diagnostic revolution currently relies on the ability to efficiently and accurately offer multiplex detection and characterization for a variety of infectious disease pathogens. Microarray analysis has the capability to offer robust multiplex detection but has just started to enter the diagnostic microbiology laboratory. Multiple microarray platforms exist, including printed double-stranded DNA and oligonucleotide arrays, in situ-synthesized arrays, high-density bead arrays, electronic microarrays, and suspension bead arrays. One aim of this paper is to review microarray technology, highlighting technical differences between them and each platform's advantages and disadvantages. Although the use of microarrays to generate gene expression data has become routine, applications pertinent to clinical microbiology continue to rapidly expand. This review highlights uses of microarray technology that impact diagnostic microbiology, including the detection and identification of pathogens, determination of antimicrobial resistance, epidemiological strain typing, and analysis of microbial infections using host genomic expression and polymorphism profiles.

Miller, Melissa B.; Tang, Yi-Wei

2009-01-01

221

Gene expression profile analysis by DNA microarrays: promise and pitfalls.  

PubMed

DNA microarrays represent a technological intersection between biology and computers that enables gene expression analysis in human tissues on a genome-wide scale. This application can be expected to prove extremely valuable for the study of the genetic basis of complex diseases. Despite the enormous promise of this revolutionary technology, there are several issues and possible pitfalls that may undermine the authority of the microarray platform. We discuss some of the conceptual, practical, statistical, and logistical issues surrounding the use of microarrays for gene expression profiling. These issues include the imprecise definition of normal in expression comparisons; the cellular and subcellular heterogeneity of the tissues being studied; the difficulty in establishing the statistically valid comparability of arrays; the logistical logjam in analysis, presentation, and archiving of the vast quantities of data generated; and the need for confirmational studies that address the functional relevance of findings. Although several complicated issues must be resolved, the potential payoff remains large. PMID:11710894

King, H C; Sinha, A A

2001-11-14

222

Biomaterial microarrays: rapid, microscale screening of polymer–cell interaction  

Microsoft Academic Search

The identification of biomaterials that induce optimal gene expression patterns and allow for appropriate levels of cellular attachment is of central importance in tissue engineering and cell therapy. Herein, we describe the creation of cell-compatible, biomaterial microarrays, that allow rapid, microscale testing of biomaterial interactions with cells. As proof of principle, we simultaneously characterized over 3456 human mesenchymal stem cell

Daniel G. Anderson; David Putnam; Erin B. Lavik; Tahir A. Mahmood; Robert Langer

2005-01-01

223

Data-adaptive test statistics for microarray data  

Microsoft Academic Search

Motivation: An important task in microarray data analysis is the selection of genes that are differentially expressed between different tissue samples, such as healthy and diseased. However, micro- array data contain an enormous number of dimensions (genes) and very few samples (arrays), a mismatch which poses fundamental statistical problems for the selection process that have defied easy resolution. Results: In

Sach Mukherjee; Stephen J. Roberts; Mark J. Van Der Laan

2005-01-01

224

Microarray platform for omics analysis  

NASA Astrophysics Data System (ADS)

Microarray technology has revolutionized genetic analysis. However, limitations in genome analysis has lead to renewed interest in establishing 'omic' strategies. As we enter the post-genomic era, new microarray technologies are needed to address these new classes of 'omic' targets, such as proteins, as well as lipids and carbohydrates. We have developed a microarray platform that combines self- assembling monolayers with the biotin-streptavidin system to provide a robust, versatile immobilization scheme. A hydrophobic film is patterned on the surface creating an array of tension wells that eliminates evaporation effects thereby reducing the shear stress to which biomolecules are exposed to during immobilization. The streptavidin linker layer makes it possible to adapt and/or develop microarray based assays using virtually any class of biomolecules including: carbohydrates, peptides, antibodies, receptors, as well as them ore traditional DNA based arrays. Our microarray technology is designed to furnish seamless compatibility across the various 'omic' platforms by providing a common blueprint for fabricating and analyzing arrays. The prototype microarray uses a microscope slide footprint patterned with 2 by 96 flat wells. Data on the microarray platform will be presented.

Mecklenburg, Michael; Xie, Bin

2001-09-01

225

Chronic treatment with tempol does not significantly ameliorate renal tissue hypoxia or disease progression in a rodent model of polycystic kidney disease.  

PubMed

In the present study, we tested whether polycystic kidney disease (PKD) is associated with renal tissue hypoxia and oxidative stress, which, in turn, contribute to the progression of cystic disease and hypertension. Lewis polycystic kidney (LPK) rats and Lewis control (Lewis) rats were treated with tempol (1 mmol/L in drinking water) from 3 to 13 weeks of age or remained untreated. The LPK rats developed polyuria, uraemia and proteinuria. At 13 weeks of age, LPK rats had greater mean arterial pressure (1.5-fold), kidney weight (sixfold) and plasma creatinine (3.5-fold) than Lewis rats. Kidneys from LPK rats were cystic and fibrotic. Renal hypoxia was evidenced by staining for pimonidazole adducts and hypoxia-inducible factor (HIF)-1? in cells lining renal cysts and upregulation of HIF-1? and its downstream targets vascular endothelial growth factor (VEGF), glucose transporter-1 (Glut-1) and heme oxygenase 1 (HO-1). However, total HO activity did not differ greatly between kidney tissue from LPK compared with Lewis rats. Renal oxidative and/or nitrosative stress was evidenced by ninefold greater immunofluorescence for 3-nitrotyrosine in kidney tissue from LPK compared with Lewis rats and a > 10-fold upregulation of mRNA for p47phox and gp91phox. Total renal superoxide dismutase (SOD) activity was sevenfold less and expression of SOD1 mRNA was 70% less in kidney tissue from LPK compared with Lewis rats. In LPK rats, tempol treatment reduced immunofluorescence for 3-nitrotyrosine and HIF1A mRNA while upregulating VEGF and p47phox mRNA expression, but otherwise had little impact on disease progression, renal tissue hypoxia or hypertension. Our findings do not support the hypothesis that oxidative stress drives hypoxia and disease progression in PKD. PMID:23006058

Ding, Alice; Kalaignanasundaram, Priyadharshani; Ricardo, Sharon D; Abdelkader, Amany; Witting, Paul K; Broughton, Brad R S; Kim, Hyun B; Wyse, Benjamin F; Phillips, Jacqueline K; Evans, Roger G

2012-11-01

226

Differentiated miRNA expression and validation of signaling pathways in apoE gene knockout mice by cross-verification microarray platform  

PubMed Central

The microRNA (miRNA) regulation mechanisms associated with atherosclerosis are largely undocumented. Specific selection and efficient validation of miRNA regulation pathways involved in atherosclerosis development may be better assessed by contemporary microarray platforms applying cross-verification methodology. A screening platform was established using both miRNA and genomic microarrays. Microarray analysis was then simultaneously performed on pooled atherosclerotic aortic tissues from 10 Apolipoprotein E (apoE) knockout mice (apoE?/?) and 10 healthy C57BL/6 (B6) mice. Differentiated miRNAs were screened and cross-verified against an mRNA screen database to explore integrative mRNA–miRNA regulation. Gene set enrichment analysis was conducted to describe the potential pathways regulated by these mRNA–miRNA interactions. High-throughput data analysis of miRNA and genomic microarrays of knockout and healthy control mice revealed 75 differentially expressed miRNAs in apoE?/? mice at a threshold value of 2. The six miRNAs with the greatest differentiation expression were confirmed by real-time quantitative reverse-transcription PCR (qRT–PCR) in atherosclerotic tissues. Significantly enriched pathways, such as the type 2 diabetes mellitus pathway, were observed by a gene-set enrichment analysis. The enriched molecular pathways were confirmed through qRT–PCR evaluation by observing the presence of suppressor of cytokine signaling 3 (SOCS3) and SOCS3-related miRNAs, miR-30a, miR-30e and miR-19b. Cross-verified high-throughput microarrays are optimally accurate and effective screening methods for miRNA regulation profiles associated with atherosclerosis. The identified SOCS3 pathway is a potentially valuable target for future development of targeted miRNA therapies to control atherosclerosis development and progression.

Han, Hui; Wang, Yu-Hong; Qu, Guang-Jin; Sun, Ting-Ting; Li, Feng-Qing; Jiang, Wei; Luo, Shan-Shun

2013-01-01

227

Immobilization of DNA on Microarrays  

Microsoft Academic Search

Microarrays are new analytical devices that allow the parallel and simultaneous detection of\\u000a thousands of target compounds. Microarrays, also called DNA chips, are widely used in gene expression,\\u000a the genotyping of individuals, point mutations, detection of single nucleotide polymorphisms, and\\u000a short tandem repeats.\\u000a \\u000a \\u000a Microarrays have highly specific base-pair interactions with labeled complementary strands,\\u000a which makes this technology to a powerful analytical

Christian Heise; Frank Bier

228

Microarray Analysis of Microbial Weathering  

NASA Astrophysics Data System (ADS)

Microarray analysis of the heavy metal resistant bacterium, Cupriavidus metallidurans CH34 was used to investigate the genes involved in the weathering. The results demonstrated that large porin and membrane transporter genes were unregulated.

Olsson-Francis, K.; van Houdt, R.; Leys, N.; Mergeay, M.; Cockell, C. S.

2010-04-01

229

Medical Image Computing and Computer-Aided Medical Interventions Applied to Soft Tissues: Work in Progress in Urology  

Microsoft Academic Search

Until recently, computer-aided medical interventions (CAMI) and medical robotics have focused on rigid and nondeformable anatomical structures. Nowadays, special attention is paid to soft tissues, raising complex issues due to their mobility and deformation. Mini-invasive digestive surgery was probably one of the first fields where soft tissues were handled through the development of simulators, tracking of anatomical structures and specific

Jocelyne Troccaz; Michael Baumann; Peter Berkelman; Philippe Cinquin; Vincent Daanen; Antoine Leroy; Maud Marchal; Yohan Payan; Emmanuel Promayon; Sandrine Voros; Stephane Bart; Michel Bolla; Emmanuel Chartier-Kastler; Jean-Luc Descotes; A. Dusserre; J.-Y. Giraud; J.-A. Long; R. Moalic; P. Mozer

2006-01-01

230

Three-dimensional lithographically-defined organotypic tissue arrays for quantitative analysis of morphogenesis and neoplastic progression  

SciTech Connect

Here we describe a simple micromolding method to construct three-dimensional arrays of organotypic epithelial tissue structures that approximate in vivo histology. An elastomeric stamp containing an array of posts of defined geometry and spacing is used to mold microscale cavities into the surface of type I collagen gels. Epithelial cells are seeded into the cavities and covered with a second layer of collagen. The cells reorganize into hollow tissues corresponding to the geometry of the cavities. Patterned tissue arrays can be produced in 3-4 h and will undergo morphogenesis over the following one to three days. The protocol can easily be adapted to study a variety of tissues and aspects of normal and neoplastic development.

Nelson, Celeste M.; Inman, Jamie L.; Bissell, Mina J.

2008-02-13

231

Does regular consumption of green tea influence expression of vascular endothelial growth factor and its receptor in aged rat erectile tissue? Possible implications for vasculogenic erectile dysfunction progression  

PubMed Central

Erectile dysfunction (ED) is a highly prevalent disease affecting millions of men worldwide with a tendency for widespread increase. ED is now considered an early manifestation of atherosclerosis and, consequently, a precursor of systemic vascular disease. Atherosclerosis and ED share potentially modifiable risk factors, as smoking or high-fat food intake, but it is unclear how regular consumption of anti-oxidant rich drinks, which exhibit recognised anti-atherosclerotic features, affects ED progression. The objective of this study was to evaluate the modulating effects of chronic consumption of catechin-rich beverages on the vascular structure of the rat corpus cavernosum, and how this could contribute to delay or prevention of the onset of ED. Male Wistar rats aged 12 months were treated with green tea (GT) or a green tea extract solution (GTE) as the only liquid source for 6 months. Consumption of GT and GTE led to decreased plasma androgen levels without any significant change in plasma lipid levels. A reduction in corpus cavernosum intracellular storage of lipids, associated with decreased expression of vascular endothelial growth factor (VEGF) and its receptor VEGFR2 in endothelial cells, was observed. Taken together, these results suggest diminished atherosclerotic progression in cavernous tissue. However, functional studies will be necessary to elucidate if catechin-rich beverages are useful compounds in the prevention of deleterious vascular events associated with ED. It was also demonstrated that regular consumption of catechins reduces atherosclerotic progression and mortality due to cardiovascular disease. The results reported here suggest diminished atherosclerotic progression in cavernous tissue in aged rats following chronic ingestion of catechin-rich beverages.

Assuncao, M.; Marques, F.; Andrade, J. P.; Almeida, H.

2008-01-01

232

Visualization-based discovery and analysis of genomic aberrations in microarray data  

PubMed Central

Background Chromosomal copy number changes (aneuploidies) play a key role in cancer progression and molecular evolution. These copy number changes can be studied using microarray-based comparative genomic hybridization (array CGH) or gene expression microarrays. However, accurate identification of amplified or deleted regions requires a combination of visual and computational analysis of these microarray data. Results We have developed ChARMView, a visualization and analysis system for guided discovery of chromosomal abnormalities from microarray data. Our system facilitates manual or automated discovery of aneuploidies through dynamic visualization and integrated statistical analysis. ChARMView can be used with array CGH and gene expression microarray data, and multiple experiments can be viewed and analyzed simultaneously. Conclusion ChARMView is an effective and accurate visualization and analysis system for recognizing even small aneuploidies or subtle expression biases, identifying recurring aberrations in sets of experiments, and pinpointing functionally relevant copy number changes. ChARMView is freely available under the GNU GPL at .

Myers, Chad L; Chen, Xing; Troyanskaya, Olga G

2005-01-01

233

Imaging the morphological change of tissue structure during the early phase of esophageal tumor progression using multiphoton microscopy  

NASA Astrophysics Data System (ADS)

Esophageal cancer is a common malignancy with a very poor prognosis. Successful strategies for primary prevention and early detection are critically needed to control this disease. Multiphoton microscopy (MPM) is becoming a novel optical tool of choice for imaging tissue architecture and cellular morphology by two-photon excited fluorescence. In this study, we used MPM to image microstructure of human normal esophagus, carcinoma in situ (CIS), and early invasive carcinoma in order to establish the morphological features to differentiate these tissues. The diagnostic features such as the appearance of cancerous cells, the significant loss of stroma, the absence of the basement membrane were extracted to distinguish between normal and cancerous esophagus tissue. These results correlated well with the paired histological findings. With the advancement of clinically miniaturized MPM and the multi-photon probe, combining MPM with standard endoscopy will therefore allow us to make a real-time in vivo diagnosis of early esophageal cancer at the cellular level.

Xu, Jian; Kang, Deyong; Xu, Meifang; Zhu, Xiaoqin; Zhuo, Shuangmu; Chen, Jianxin

2012-12-01

234

Intracardiac thrombus formation with rapidly progressive heart failure in the neonate: treatment with tissue type plasminogen activator  

Microsoft Academic Search

A newborn is described in whom the use of a central venous line was complicated by septicaemia and by intracardiac thrombus formation with tricuspid valve insufficiency and heart failure. Besides antibiotics, treatment consisted of tissue type plasminogen activator (tPA) for three days. This treatment resulted in the disappearance of the thrombus and the tricuspid insufficiency. No adverse effects were noted.

B Van Overmeire; P J Van Reempts; K J Van Acker

1992-01-01

235

The changes in various hydroxyproline fractions in aortic tissue of rabbits are closely related to the progression of atherosclerosis  

Microsoft Academic Search

BACKGROUND: The most important function of collagen and elastin is to induce several mechanical parameters which are known to play a dominant role in governing mechanical properties of the blood vessels. The aortic tissue of rabbit is one of the important sources of collagen and elastin. The effects of high fat diet (HFD) on the hydroxyproline (Hyp) fractions in serum

Mohamed Anwar K Abdelhalim; NJ Siddiqi; AS Alhomida; Mohammed S Al-Ayed

2010-01-01

236

Assessment of coronary atherosclerosis by IVUS and IVUS-based imaging modalities: progression and regression studies, tissue composition and beyond  

Microsoft Academic Search

Cardiovascular disease remains the leading cause of mortality, morbidity and disability in the developed world, predominantly\\u000a affecting the adult population. In the early 1990s coronary heart disease (CHD) was established as affecting one in two men\\u000a and one in three women by the age of forty. Despite the dramatic progress in the field of cardiovascular medicine in terms\\u000a of diagnosis

Bill D. Gogas; Vasim Farooq; Patrick W. Serruys; Hector M. Garcìa-Garcìa

2011-01-01

237

Energy restriction prevents the development of type 2 diabetes in Zucker diabetic fatty rats: coordinated patterns of gene expression for energy metabolism in insulin-sensitive tissues and pancreatic islets determined by oligonucleotide microarray analysis  

Microsoft Academic Search

Energy restriction (ER) causes metabolic improvement in the prediabetic and diabetic state. Little information exists on the mechanism of action of ER, for example, on the changes at the transcriptional gene level in insulin-sensitive tissues. To gain further insight, we have investigated changes in gene expressions in skeletal muscle, liver, fat, and pancreatic islets after ER in male Zucker diabetic

Michele Colombo; Mogens Kruhoeffer; Soeren Gregersen; Andreas Agger; PerBendix Jeppesen; Torben Oerntoft; Kjeld Hermansen

2006-01-01

238

Chromatin patterns associated with lung adenocarcinoma progression  

PubMed Central

The development and progression of lung adenocarcinoma, one of the most common cancers, is driven by the interplay of genetic and epigenetic changes and the role of chromatin structure in malignant transformation remains poorly understood. We used systematic nucleosome distribution and chromatin accessibility microarray mapping platforms to analyze the genome-wide chromatin structure from normal tissues and from primary lung adenocarcinoma of different grades and stages. We identified chromatin-based patterns across different patients with lung adenocarcinoma of different cancer grade and stage. Low-grade cancers had nucleosome distributions very different compared with the corresponding normal tissue but had nearly identical chromatin accessibility. Conversely, nucleosome distributions of high-grade cancers showed few differences. Substantial disruptions in chromosomal accessibility were seen in a patient with a high-grade and high-stage tumor. These data imply that chromatin structure changes during the progression of lung adenocarcinoma. We have therefore developed a model in which low-grade lung adenocarcinomas are linked to changes in nucleosome distributions, whereas higher-grade tumors are linked to large-scale chromosomal changes. These results provide a foundation for the development of a comprehensive framework linking the general and locus-specific roles of chromatin structure to lung cancer progression. We propose that this strategy has the potential to identify a new class of chromatin-based diagnostic, prognostic and therapeutic markers in cancer progression.

Druliner, Brooke R.; Fincher, Justin A.; Sexton, Brittany S.; Vera, Daniel L.; Roche, Michael; Lyle, Stephen; Dennis, Jonathan H.

2013-01-01

239

Differential splicing using whole-transcript microarrays  

PubMed Central

Background The latest generation of Affymetrix microarrays are designed to interrogate expression over the entire length of every locus, thus giving the opportunity to study alternative splicing genome-wide. The Exon 1.0 ST (sense target) platform, with versions for Human, Mouse and Rat, is designed primarily to probe every known or predicted exon. The smaller Gene 1.0 ST array is designed as an expression microarray but still interrogates expression with probes along the full length of each well-characterized transcript. We explore the possibility of using the Gene 1.0 ST platform to identify differential splicing events. Results We propose a strategy to score differential splicing by using the auxiliary information from fitting the statistical model, RMA (robust multichip analysis). RMA partitions the probe-level data into probe effects and expression levels, operating robustly so that if a small number of probes behave differently than the rest, they are downweighted in the fitting step. We argue that adjacent poorly fitting probes for a given sample can be evidence of differential splicing and have designed a statistic to search for this behaviour. Using a public tissue panel dataset, we show many examples of tissue-specific alternative splicing. Furthermore, we show that evidence for putative alternative splicing has a strong correspondence between the Gene 1.0 ST and Exon 1.0 ST platforms. Conclusion We propose a new approach, FIRMAGene, to search for differentially spliced genes using the Gene 1.0 ST platform. Such an analysis complements the search for differential expression. We validate the method by illustrating several known examples and we note some of the challenges in interpreting the probe-level data. Software implementing our methods is freely available as an R package.

Robinson, Mark D; Speed, Terence P

2009-01-01

240

Image microarrays (IMA): Digital pathology's missing tool  

PubMed Central

Introduction: The increasing availability of whole slide imaging (WSI) data sets (digital slides) from glass slides offers new opportunities for the development of computer-aided diagnostic (CAD) algorithms. With the all-digital pathology workflow that these data sets will enable in the near future, literally millions of digital slides will be generated and stored. Consequently, the field in general and pathologists, specifically, will need tools to help extract actionable information from this new and vast collective repository. Methods: To address this limitation, we designed and implemented a tool (dCORE) to enable the systematic capture of image tiles with constrained size and resolution that contain desired histopathologic features. Results: In this communication, we describe a user-friendly tool that will enable pathologists to mine digital slides archives to create image microarrays (IMAs). IMAs are to digital slides as tissue microarrays (TMAs) are to cell blocks. Thus, a single digital slide could be transformed into an array of hundreds to thousands of high quality digital images, with each containing key diagnostic morphologies and appropriate controls. Current manual digital image cut-and-paste methods that allow for the creation of a grid of images (such as an IMA) of matching resolutions are tedious. Conclusion: The ability to create IMAs representing hundreds to thousands of vetted morphologic features has numerous applications in education, proficiency testing, consensus case review, and research. Lastly, in a manner analogous to the way conventional TMA technology has significantly accelerated in situ studies of tissue specimens use of IMAs has similar potential to significantly accelerate CAD algorithm development.

Hipp, Jason; Cheng, Jerome; Pantanowitz, Liron; Hewitt, Stephen; Yagi, Yukako; Monaco, James; Madabhushi, Anant; Rodriguez-canales, Jaime; Hanson, Jeffrey; Roy-Chowdhuri, Sinchita; Filie, Armando C.; Feldman, Michael D.; Tomaszewski, John E.; Shih, Natalie NC.; Brodsky, Victor; Giaccone, Giuseppe; Emmert-Buck, Michael R.; Balis, Ulysses J.

2011-01-01

241

EXOGENOUS NUCLEIC ACID CONTROLS FOR DNA OLIGO MICROARRAYS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The reliability of microarray data is critical for obtaining meaningful biological insights from genomic expression analysis. Quality control of microarray experiments is an important element for microarray data handling and variation estimate of microarray experiments. In generating fungal and ba...

242

Genomic microarrays: a technology overview.  

PubMed

Genomic microarrays are now widely used diagnostically for the molecular karyotyping of patients with intellectual disability, congenital anomalies and autistic spectrum disorder and have more recently been applied for the detection of genomic imbalances in prenatal genetic diagnosis. We present an overview of the different arrays, protocols used and discuss methods of genomic array data analysis. PMID:22467164

Brady, Paul D; Vermeesch, Joris R

2012-04-01

243

DNA Microarray Methodology - Flash Animation  

NSDL National Science Digital Library

This animation demonstrates how DNA microarray experiments are performed. DNA chips are used to determine which genes are activated and which genes are repressed when two populations are compared. In this case, the comparison is between yeast cells grown under either aerobic or anaerobic conditions. This animation is very effective for many different education levels. Teachers and students love this one.

Campbell, A. M.

2012-04-12

244

Microarray analysis: Uses and Limitations  

Technology Transfer Automated Retrieval System (TEKTRAN)

The use of microarray technology has exploded in resent years. All areas of biological research have found application for this powerful platform. From human disease studies to microbial detection systems, a plethora of uses for this technology are currently in place with new uses being developed ...

245

Solid supports for microarray immunoassays  

Microsoft Academic Search

Stimulated by the achievements of the first phase in genomics and the resulting need of assigning functions to the acquired sequence information, novel formats of immunoassays are being developed for high- throughput multi-analyte studies. In principle, they are similar in nature to the microarray assays already established at the level of nucleic acids. However, the biochemical diversity and the sheer

Wlad Kusnezow

2003-01-01

246

Extracellular Matrix, Nuclear and Chromatin Structure and GeneExpression in Normal Tissues and Malignant Tumors: A Work inProgress  

SciTech Connect

Almost three decades ago, we presented a model where theextracellular matrix (ECM) was postulated to influence gene expressionand tissue-specificity through the action of ECM receptors and thecytoskeleton. This hypothesis implied that ECM molecules could signal tothe nucleus and that the unit of function in higher organisms was not thecell alone, but the cell plus its microenvironment. We now know that ECMinvokes changes in tissue and organ architecture and that tissue, cell,nuclear, and chromatin structure are changed profoundly as a result ofand during malignant progression. Whereas some evidence has beengenerated for a link between ECM-induced alterations in tissuearchitecture and changes in both nuclear and chromatin organization, themanner by which these changes actively induce or repress gene expressionin normal and malignant cells is a topic in need of further attention.Here, we will discuss some key findings that may provide insights intomechanisms through which ECM could influence gene transcription and howtumor cells acquire the ability to overcome these levels ofcontrol.

Spencer, Virginia A.; Xu, Ren; Bissell, Mina J.

2006-08-01

247

The Microarray Revolution: Perspectives from Educators  

ERIC Educational Resources Information Center

|In recent years, microarray analysis has become a key experimental tool, enabling the analysis of genome-wide patterns of gene expression. This review approaches the microarray revolution with a focus upon four topics: 1) the early development of this technology and its application to cancer diagnostics; 2) a primer of microarray research,…

Brewster, Jay L.; Beason, K. Beth; Eckdahl, Todd T.; Evans, Irene M.

2004-01-01

248

Direct calibration of PICKY-designed microarrays  

PubMed Central

Background Few microarrays have been quantitatively calibrated to identify optimal hybridization conditions because it is difficult to precisely determine the hybridization characteristics of a microarray using biologically variable cDNA samples. Results Using synthesized samples with known concentrations of specific oligonucleotides, a series of microarray experiments was conducted to evaluate microarrays designed by PICKY, an oligo microarray design software tool, and to test a direct microarray calibration method based on the PICKY-predicted, thermodynamically closest nontarget information. The complete set of microarray experiment results is archived in the GEO database with series accession number GSE14717. Additional data files and Perl programs described in this paper can be obtained from the website under the PICKY Download area. Conclusion PICKY-designed microarray probes are highly reliable over a wide range of hybridization temperatures and sample concentrations. The microarray calibration method reported here allows researchers to experimentally optimize their hybridization conditions. Because this method is straightforward, uses existing microarrays and relatively inexpensive synthesized samples, it can be used by any lab that uses microarrays designed by PICKY. In addition, other microarrays can be reanalyzed by PICKY to obtain the thermodynamically closest nontarget information for calibration.

Chou, Hui-Hsien; Trisiriroj, Arunee; Park, Sunyoung; Hsing, Yue-Ie C; Ronald, Pamela C; Schnable, Patrick S

2009-01-01

249

Meta-coexpression conservation analysis of microarray data: a \\  

Microsoft Academic Search

BACKGROUND: Alterations in brain-derived neurotrophic factor (BDNF) gene expression contribute to serious pathologies such as depression, epilepsy, cancer, Alzheimer's, Huntington and Parkinson's disease. Therefore, exploring the mechanisms of BDNF regulation represents a great clinical importance. Studying BDNF expression remains difficult due to its multiple neural activity-dependent and tissue-specific promoters. Thus, microarray data could provide insight into the regulation of this

Tamara Aid-Pavlidis; Pavlos Pavlidis; Tõnis Timmusk

2009-01-01

250

DNA microarrays: sample quality control, array hybridization and scanning.  

PubMed

Microarray expression profiling of the nervous system provides a powerful approach to identifying gene activities in different stages of development, different physiological or pathological states, response to therapy, and, in general, any condition that is being experimentally tested. Expression profiling of neural tissues requires isolation of high quality RNA, amplification of the isolated RNA and hybridization to DNA microarrays. In this article we describe protocols for reproducible microarray experiments from brain tumor tissue. We will start by performing a quality control analysis of isolated RNA samples with Agilent's 2100 Bioanalyzer "lab-on-a-chip" technology. High quality RNA samples are critical for the success of any microarray experiment, and the 2100 Bioanalyzer provides a quick, quantitative measurement of the sample quality. RNA samples are then amplified and labeled by performing reverse transcription to obtain cDNA, followed by in vitro transcription in the presence of labeled nucleotides to produce labeled cRNA. By using a dual-color labeling kit, we will label our experimental sample with Cy3 and a reference sample with Cy5. Both samples will then be combined and hybridized to Agilent's 4x44 K arrays. Dual-color arrays offer the advantage of a direct comparison between two RNA samples, thereby increasing the accuracy of the measurements, in particular for small changes in expression levels, because the two RNA samples are hybridized competitively to a single microarray. The arrays will be scanned at the two corresponding wavelengths, and the ratio of Cy3 to Cy5 signal for each feature will be used as a direct measurement of the relative abundance of the corresponding mRNA. This analysis identifies genes that are differentially expressed in response to the experimental conditions being tested. PMID:21445042

Diaz, Elva; Barisone, Gustavo A

2011-03-15

251

Genome-wide analysis of mouse transcripts using exon microarrays and factor graphs  

Microsoft Academic Search

Recent mammalian microarray experiments detected widespread transcription and indicated that there may be many undiscovered multiple-exon protein-coding genes. To explore this possibility, we labeled cDNA from unamplified, polyadenylation-selected RNA samples from 37 mouse tissues to microarrays encompassing 1.14 million exon probes. We analyzed these data using GenRate, a Bayesian algorithm that uses a genome-wide scoring function in a factor graph

Brendan J Frey; Naveed Mohammad; Quaid D Morris; Wen Zhang; Mark D Robinson; Sanie Mnaimneh; Richard Chang; Qun Pan; Eric Sat; Janet Rossant; Benoit G Bruneau; Jane E Aubin; Benjamin J Blencowe; Timothy R Hughes

2005-01-01

252

An ensemble method for gene discovery based on DNA microarray data  

Microsoft Academic Search

The advent of DNA microarray technology has offered the promise of casting new insights onto deciphering secrets of life by\\u000a monitoring activities of thousands of genes simultaneously. Current analyses of microarray data focus on precise classification\\u000a of biological types, for example, tumor versus normal tissues. A further scientific challenging task is to extract disease-relevant\\u000a genes from the bewildering amounts of

Xia Li; Shaoqi Rao; Tianwen Zhang; Zheng Guo; Qingpu Zhang; Kathy L. Moser; Eric J. Topol

2004-01-01

253

Progress in culture and subculture of spheroplasts and fastidious acid-fast bacilli isolated from intestinal tissues.  

PubMed Central

The efficiency of culture media was compared for the culture and subculture of very slowly growing acid-fast bacilli and spheroplast forms obtained from intestinal tissues of patients with Crohn's disease and ulcerative colitis and from controls without inflammatory bowel disease. Media were developed by modifying a nutrient broth medium based on veal infusion broth and yeast extract. We evaluated the effects of pH and the addition of Tween 80, Dubo oleic albumin complex, an extract from intestinal tissue from a patient with Crohn's disease, horse serum, sucrose, magnesium sulfate, ferrous ammonium sulfate, and sodium citrate. All media contained mycobactin J (2 micrograms/ml). We developed a medium (MG3) which was highly successful in promoting the growth of very fastidious organisms and promoted reversion of spheroplasts to acid-fast rods. MG3 contained veal infusion broth, 1% yeast extract, 10% horse serum, 0.3 M sucrose, 0.2% MgSO4, 0.1% ferrous ammonium sulfate, 0.1% sodium citrate, and 2 mg of mycobactin J per liter. We were able to obtain quantities of organisms sufficient for examination of the organisms by molecular techniques. Successful cultivation of all isolates and reversion of spheroplasts to acid-fast forms encourage further studies of the possibility of a complex association of mycobacteria and Crohn's disease. Images

Markesich, D C; Graham, D Y; Yoshimura, H H

1988-01-01

254

Use of microarrays to find novel regulators of periodontal ligament fibroblast differentiation  

Microsoft Academic Search

Periodontal regeneration requires the coordinated movement and differentiation of several cell types in order to re-establish the cementum, periodontal ligament (PDL), and alveolar bone. Cells in culture are often used as model systems for mature tissues, although they may represent expanded progenitor cell populations. Comparison of transcript expression between fresh PDL tissue and PDL cell isolates by MicroArray analysis has

Thomas E. Lallier; Amber Spencer

2007-01-01

255

Overexpression of carbonic anhydrase IX (CAIX) in vulvar cancer is associated with tumor progression and development of locoregional lymph node metastases  

Microsoft Academic Search

Carbonic anhydrase IX (CAIX) is a strictly membranous expressed metalloenzyme involved in cell adhesion, pH homeostasis, and\\u000a cancer progression. The protein is specifically overexpressed in a wide variety of malignant tumors. This study was designed\\u000a to assess the role of CAIX in primary vulvar cancer. One hundred forty-two well-characterized primary vulvar carcinomas were\\u000a analyzed on a tissue microarray (TMA). Three

Matthias Choschzick; Linn Woelber; Stephan Hess; Christine zu Eulenburg; Jörg Schwarz; Ronald Simon; Sven Mahner; Fritz Jaenicke; Volkmar Müller

2010-01-01

256

Generalized rank tests for replicated microarray data.  

PubMed

Gene expression data from microarray experiments have been studied using several statistical models. Significance Analysis of Microarrays (SAM), for example, has proved to be useful in analyzing microarray data. In the spirit of the SAM procedures, we develop permutation based rank-tests for generalized Wilcoxon ranksum test for two-group comparisons of replicated microarray data. Also, for microarray experiments with randomized block design, we consider generalized signed rank test. The statistical analysis software package is written in R and is freely available in a package. PMID:16646848

Lee, Mei-Ling Ting; Gray, Robert J; Björkbacka, Harry; Freeman, Mason W

2005-01-28

257

Automated cDNA Microarray Image Segmentation  

NASA Astrophysics Data System (ADS)

cDNA microarray technology enables whole genome study of gene expressions by measuring the differential expression of genes in microarray images. An important first step in analyzing microarray image is the accurate delineation of the cDNA spots in the image. We report here a fully automated spot segmentation algorithm for cDNA microarray images. The algorithm makes use of morphological operations, adaptive multi-level thresholding, and statistical intensity modeling to perform automatic grid addressing and spot segmentation. Our algorithm is robust for even poor quality cDNA microarray images.

Liew, Alan Wee-Chung; Yan, Hong

2007-11-01

258

Protein Microarrays for Quantitative Detection of PAI-1 in Serum  

PubMed Central

Objective Plasminogen activator inhibitor-1 (PAI-1), one crucial component of the plasminogen activator system, is a major player in the pathogenesis of many vascular diseases as well as in cancer. High levels of PAI-1 in breast cancer tissue are associated with poor prognosis. The aim of this study is to evaluate rigorously the potential of serum PAI-1 concentration functioning as a general screening test in diagnostic or prognostic assays. Methods A protein-microarray-based sandwich fluorescence immunoassay (FIA) was developed to detect PAI-1 in serum. Several conditions of this microarray-based FIA were optimized to establish an efficacious method. Serum specimens of 84 healthy women and 285 women with breast cancer were analyzed using the optimized FIA microarray. Results The median serum PAI-1 level of breast cancer patients was higher than that of healthy women (109.7 ng/ml vs. 63.4 ng/ml). Analysis of covariance revealed that PAI-1 levels of the two groups were significantly different (P<0.001) when controlling for an age effect on PAI-1 levels. However, PAI-1 values in TNM stage I?IV patients respectively were not significantly different from each other. Conclusion This microarray-based sandwich FIA holds potential for quantitative analysis of tumor markers such as PAI-1.

Ma, Xu

2012-01-01

259

Lung cancer in uranium miners: A tissue resource and pilot study. Progress report, September 25, 1992--May 31, 1993  

SciTech Connect

This project involves two related activities directed toward understanding respiratory carcinogenesis in radon-exposed former uranium miners. The first activity involves a continuation of the tissue resource of lung cancer cases from former underground uranium miners and comparison cases from non-miners. The second activity is a pilot study for a proposed longitudinal study of respiratory carcinogenesis in former uranium miners. The objectives are to facilitate the investigation of molecular changes in radon exposed lung cancer cases and to develop methods for prospectively studying clinical, cytologic, cytogenetic, and molecular changes in the multi-event process of respiratory carcinogenesis, and to assess the feasibility of recruiting former uranium miners into a longitudinal study that collects multiple biologic specimens.

Samet, J.M.

1993-05-01

260

Periostin: novel tissue and urinary biomarker of progressive renal injury induces a coordinated mesenchymal phenotype in tubular cells  

PubMed Central

Background Periostin acts as an adhesion molecule during bone formation. Knowledge of its expression in kidney injury is scant. Methods We investigated periostin function and expression in vivo in Sprague–Dawley rats after 5/6 nephrectomy (Nx), in DBA2J mice with streptozotocin-induced diabetic nephropathy (SZ-DN) and unilateral ureteral obstruction (UUO) and in vitro in mouse distal collecting tubular cells (MDCT) and in tissue and urine from chronic kidney disease (CKD) patients. Results Periostin messenger RNA was increased after 5/6Nx and SZ-DN demonstrating generalizability of the increment in renal injury. Periostin was expressed predominantly in distal tubule (DT) epithelial cell cytoplasm in situ, in cells shed into the lumen, and, in lesser abundance, in glomeruli undergoing obsolescence, arterioles and in the tubulointerstitium in extracellular and intracellular locations. In affected DT after 5/6Nx, periostin expression appeared de novo, E-cadherin became undetectable and tubule cells displayed the mesenchymal marker proteins fibroblast-specific protein-1 (FSP1) and matrix metalloproteinase-9 (MMP9). Periostin overexpression in cultured MDCT cells dramatically induced MMP9 and FSP1 protein and suppressed E-cadherin. Periostin short interfering RNA blocked these changes. Urine periostin excretion increased over time after 5/6Nx, and it was also excreted in the urine of CKD patients. Urine periostin enzyme-linked immunosorbent assay at a cutoff of 32.66 pg/mg creatinine demonstrated sensitivity and specificity for distinguishing patients with CKD from healthy people (92.3 and 95.0%, respectively) comparing favorably with urine neutrophil gelatinase-associated lipocalin. Conclusion These data demonstrate that periostin is a mediator and marker of tubular dedifferentiation and a promising tissue and urine biomarker for kidney injury in experimental models and in clinical renal disease.

Satirapoj, Bancha; Wang, Ying; Chamberlin, Mina P.; Dai, Tiane; LaPage, Janine; Phillips, Lynetta; Nast, Cynthia C.; Adler, Sharon G.

2012-01-01

261

JC Papovavirus Large Tumor (T)-Antigen Expression in Brain Tissue of Acquired Immune Deficiency Syndrome (AIDS) and Non-AIDS Patients with Progressive Multifocal Leukoencephalopathy  

NASA Astrophysics Data System (ADS)

Progressive multifocal leukoencephalopathy (PML) is a JC papovavirus infection of the central nervous system in immunocompromised patients. It is well established that demyelination in PML is caused by JC virus infection of oligodendroglia, but whether the nonstructural regulatory protein, large tumor (T) antigen, is detectable in infected human tissue was not known. Using a modification of the peroxidase-antiperoxidase technique, we found T antigen expressed in the nuclei of cells in virus-infected sites in five cases of PML studied, including two with acquired immune deficiency syndrome (AIDS). PML occurs in AIDS at a much higher frequency than in other immunosuppressive disorders, and PML in AIDS may represent a more severe form of JC virus infection of the central nervous system.

Stoner, Gerald L.; Ryschkewitsch, Caroline F.; Walker, Duard L.; Webster, Henry De F.

1986-04-01

262

Self-Assembling Protein Microarrays  

NASA Astrophysics Data System (ADS)

Protein microarrays provide a powerful tool for the study of protein function. However, they are not widely used, in part because of the challenges in producing proteins to spot on the arrays. We generated protein microarrays by printing complementary DNAs onto glass slides and then translating target proteins with mammalian reticulocyte lysate. Epitope tags fused to the proteins allowed them to be immobilized in situ. This obviated the need to purify proteins, avoided protein stability problems during storage, and captured sufficient protein for functional studies. We used the technology to map pairwise interactions among 29 human DNA replication initiation proteins, recapitulate the regulation of Cdt1 binding to select replication proteins, and map its geminin-binding domain.

Ramachandran, Niroshan; Hainsworth, Eugenie; Bhullar, Bhupinder; Eisenstein, Samuel; Rosen, Benjamin; Lau, Albert Y.; C. Walter, Johannes; LaBaer, Joshua

2004-07-01

263

p53 and Beta-Catenin Expression in Gallbladder Tissues and Correlation with Tumor Progression in Gallbladder Cancer  

PubMed Central

Background/Aim: The inactivation of the tumor suppressor gene and activation of the proto-oncogene are key steps in the development of human cancer. p53 and beta-catenin are examples of such genes, respectively. In the present study, our aim was to determine the role of these genes in the carcinogenesis of the gallbladder by immunohistochemistry. Patients and Methods: Sections from paraffin-embedded blocks of surgically resected specimens of gallbladder cancer (GBC) (80 cases), chronic cholecystitis (60 cases), and control gallbladders (10 cases) were stained with the monoclonal antibody p53, and polyclonal antibody beta-catenin. Results were scored semiquantitatively and statistical analysis performed. p53 expression was scored as percentage of the nuclei stained. Beta-catenin expression was scored as type of expression–membranous, cytoplasmic, and nuclear staining. Beta-catenin expression was correlated with tumor invasiveness, differentiation, and stage. Results: Over-expression of p53 was seen in 56.25% of GBC cases and was not seen in chronic cholecystitis or in control gallbladders. p53 expression in gallbladder cancer was significantly higher than in inflammatory or control gallbladders (P < 0.0001). p53 expression increased with increasing tumor grade (P = 0.039). Beta-catenin nuclear expression was seen in 75% cases of gallbladder cancer and in no case of chronic cholecystitis and control gallbladder. Beta-catenin nuclear expression increased with tumor depth invasiveness, and grade (P = 0.028 and P = 0.0152, respectively). Conclusion: p53 and beta-catenin nuclear expression is significantly higher in GBC. p53 expression correlates with increasing tumor grade while beta-catenin nuclear expression correlates with tumor grade and depth of invasion, thus suggesting a role for these genes in tumor progression of GBC.

Ghosh, Mila; Sakhuja, Puja; Singh, Shivendra; Agarwal, Anil K.

2013-01-01

264

Gene expression profiling in peanut using high density oligonucleotide microarrays  

PubMed Central

Background Transcriptome expression analysis in peanut to date has been limited to a relatively small set of genes and only recently has a significant number of ESTs been released into the public domain. Utilization of these ESTs for oligonucleotide microarrays provides a means to investigate large-scale transcript responses to a variety of developmental and environmental signals, ultimately improving our understanding of plant biology. Results We have developed a high-density oligonucleotide microarray for peanut using 49,205 publicly available ESTs and tested the utility of this array for expression profiling in a variety of peanut tissues. To identify putatively tissue-specific genes and demonstrate the utility of this array for expression profiling in a variety of peanut tissues, we compared transcript levels in pod, peg, leaf, stem, and root tissues. Results from this experiment showed 108 putatively pod-specific/abundant genes, as well as transcripts whose expression was low or undetected in pod compared to peg, leaf, stem, or root. The transcripts significantly over-represented in pod include genes responsible for seed storage proteins and desiccation (e.g., late-embryogenesis abundant proteins, aquaporins, legumin B), oil production, and cellular defense. Additionally, almost half of the pod-abundant genes represent unknown genes allowing for the possibility of associating putative function to these previously uncharacterized genes. Conclusion The peanut oligonucleotide array represents the majority of publicly available peanut ESTs and can be used as a tool for expression profiling studies in diverse tissues.

Payton, Paxton; Kottapalli, Kameswara Rao; Rowland, Diane; Faircloth, Wilson; Guo, Baozhu; Burow, Mark; Puppala, Naveen; Gallo, Maria

2009-01-01

265

High quality protein microarray using in situ protein purification  

PubMed Central

Background In the postgenomic era, high throughput protein expression and protein microarray technologies have progressed markedly permitting screening of therapeutic reagents and discovery of novel protein functions. Hexa-histidine is one of the most commonly used fusion tags for protein expression due to its small size and convenient purification via immobilized metal ion affinity chromatography (IMAC). This purification process has been adapted to the protein microarray format, but the quality of in situ His-tagged protein purification on slides has not been systematically evaluated. We established methods to determine the level of purification of such proteins on metal chelate-modified slide surfaces. Optimized in situ purification of His-tagged recombinant proteins has the potential to become the new gold standard for cost-effective generation of high-quality and high-density protein microarrays. Results Two slide surfaces were examined, chelated Cu2+ slides suspended on a polyethylene glycol (PEG) coating and chelated Ni2+ slides immobilized on a support without PEG coating. Using PEG-coated chelated Cu2+ slides, consistently higher purities of recombinant proteins were measured. An optimized wash buffer (PBST) composed of 10 mM phosphate buffer, 2.7 mM KCl, 140 mM NaCl and 0.05% Tween 20, pH 7.4, further improved protein purity levels. Using Escherichia coli cell lysates expressing 90 recombinant Streptococcus pneumoniae proteins, 73 proteins were successfully immobilized, and 66 proteins were in situ purified with greater than 90% purity. We identified several antigens among the in situ-purified proteins via assays with anti-S. pneumoniae rabbit antibodies and a human patient antiserum, as a demonstration project of large scale microarray-based immunoproteomics profiling. The methodology is compatible with higher throughput formats of in vivo protein expression, eliminates the need for resin-based purification and circumvents protein solubility and denaturation problems caused by buffer exchange steps and freeze-thaw cycles, which are associated with resin-based purification, intermittent protein storage and deposition on microarrays. Conclusion An optimized platform for in situ protein purification on microarray slides using His-tagged recombinant proteins is a desirable tool for the screening of novel protein functions and protein-protein interactions. In the context of immunoproteomics, such protein microarrays are complimentary to approaches using non-recombinant methods to discover and characterize bacterial antigens.

Kwon, Keehwan; Grose, Carissa; Pieper, Rembert; Pandya, Gagan A; Fleischmann, Robert D; Peterson, Scott N

2009-01-01

266

Analysis of Protein Glycosylation and Phosphorylation Using Liquid Phase Separation, Protein Microarray Technology, and Mass Spectrometry  

PubMed Central

Summary Protein glycosylation and phosphorylation are very common posttranslational modifications. The alteration of these modifications in cancer cells is closely related to the onset and progression of cancer and other disease states. In this protocol, strategies for monitoring the changes in protein glycosylation and phosphorylation in serum or tissue cells on a global scale and specifically characterizing these alterations are included. The technique is based on lectin affinity enrichment for glycoproteins, all liquid-phase two-dimensional fractionation, protein microarray, and mass spectrometry technology. Proteins are separated based on pI in the first dimension using chromatofocusing (CF) or liquid isoelectric focusing (IEF) followed by the second-dimension separation using nonporous silica RP-HPLC. Five lectins with different binding specificities to glycan structures are used for screening glycosylation patterns in human serum through a biotin–streptavidin system. Fluorescent phosphodyes and phosphospecific antibodies are employed to detect specific phosphorylated proteins in cell lines or human tissues. The purified proteins of interest are identified by peptide sequencing. Their modifications including glycosylation and phosphorylation could be further characterized by mass-spectrometry-based approaches. These strategies can be used in biological samples for large-scale glycoproteome/phosphoproteome screening as well as for individual protein modification analysis.

Zhao, Jia; Patwa, Tasneem H.; Pal, Manoj; Qiu, Weilian; Lubman, David M.

2010-01-01

267

Semiconductor quantum dots for multiplexed bio-detection on solid-state microarrays.  

PubMed

Understanding cellular systems requires identification and analysis of their multiple components and determination of how they act together and are regulated. Microarray technology is one of the few tools that is able to solve such problems. It is based on high-throughput recognition of a target to the probe and has the potential to simultaneously measure the presence of numerous molecules in multiplexed tests, all contained in a small drop of test fluid. Microarrays allow the parallel analysis of genomic or proteomic content in healthy versus disease-affected or altered tissues or cells. The signal read-out from the microarrays is done with organic dyes which often suffer of photobleaching, low brightness and background fluorescence. Recent data show that the use of fluorescent nanocrystals named "quantum dots" (QDs) allows to push these limits away. QDs are sufficiently bright to be detected as individual particles, extremely resistant against photobleaching and provide unique possibilities for multiplexing, thus supplying the microarray technology with a novel read-out option enabling the sensitivity of detection to reach the single-molecule level. This paper reviews QDs applications to microarray-based detection and demonstrates how the combination of microarray and QDs technologies may increase sensitivity and highly parallel capacities of multiplexed microarrays. Such a combination should provide the breakthrough results in drug discovery, cancer diagnosis and establish new therapeutic approaches through the identification of binding target molecules and better understanding of cell signalling pathways. PMID:19467882

Rousserie, Gilles; Sukhanova, Alyona; Even-Desrumeaux, Klervi; Fleury, Fabrice; Chames, Patrick; Baty, Daniel; Oleinikov, Vladimir; Pluot, Michel; Cohen, Jacques H M; Nabiev, Igor

2009-05-20

268

An open-access long oligonucleotide microarray resource for analysis of the human and mouse transcriptomes  

PubMed Central

Two collections of oligonucleotides have been designed for preparing pangenomic human and mouse microarrays. A total of 148?993 and 121?703 oligonucleotides were designed against human and mouse transcripts. Quality scores were created in order to select 25?342 human and 24?109 mouse oligonucleotides. They correspond to: (i) a BLAST-specificity score; (ii) the number of expressed sequence tags matching each probe; (iii) the distance to the 3? end of the target mRNA. Scores were also used to compare in silico the two microarrays with commercial microarrays. The sets described here, called RNG/MRC collections, appear at least as specific and sensitive as those from the commercial platforms. The RNG/MRC collections have now been used by an Anglo-French consortium to distribute more than 3500 microarrays to the academic community. Ad hoc identification of tissue-specific transcripts and a ?80% correlation with hybridizations performed on Affymetrix GeneChip™ suggest that the RNG/MRC microarrays perform well. This work provides a comprehensive open resource for investigators working on human and mouse transcriptomes, as well as a generic method to generate new microarray collections in other organisms. All information related to these probes, as well as additional information about commercial microarrays have been stored in a freely-accessible database called MEDIANTE.

Brigand, Kevin Le; Russell, Roslin; Moreilhon, Chimene; Rouillard, Jean-Marie; Jost, Bernard; Amiot, Franck; Magnone, Virginie; Bole-Feysot, Christine; Rostagno, Philippe; Virolle, Virginie; Defamie, Virginie; Dessen, Philippe; Williams, Gary; Lyons, Paul; Rios, Geraldine; Mari, Bernard; Gulari, Erdogan; Kastner, Philippe; Gidrol, Xavier; Freeman, Tom C.; Barbry, Pascal

2006-01-01

269

Microarray data classification based on ensemble independent component selection.  

PubMed

Independent component analysis (ICA) has been widely deployed to the analysis of microarray datasets. Although it was pointed out that after ICA transformation, different independent components (ICs) are of different biological significance, the IC selection problem is still far from fully explored. In this paper, we propose a genetic algorithm (GA) based ensemble independent component selection (EICS) system. In this system, GA is applied to select a set of optimal IC subsets, which are then used to build diverse and accurate base classifiers. Finally, all base classifiers are combined with majority vote rule. To show the validity of the proposed method, we apply it to classify three DNA microarray data sets involving various human normal and tumor tissue samples. The experimental results show that our ensemble method obtains stable and satisfying classification results when compared with several existing methods. PMID:19716554

Liu, Kun-Hong; Li, Bo; Wu, Qing-Qiang; Zhang, Jun; Du, Ji-Xiang; Liu, Guo-Yan

2009-08-28

270

Quality assessment of microarray data in a multicenter study.  

PubMed

Issues implicit in a multicenter microarray study are protocol standardization and monitoring center adherence to established protocols. This study explored the effects of submitting center and sample preservation method on the quality of isolated RNA. In addition, the effects of sample preservation method and laboratory on microarray quality were also examined. Herein we evaluated the contribution of specific technical factors [center, laboratory, and preservation method (frozen/RNAlater)] on quality of isolated RNA, cRNA synthesis products, and reproducibility of gene expression microarray data for independent biologic samples collected in a multicenter microarray study. The Kruskal-Wallis test was used to test for differences owing to submitting center on isolated RNA quality. Mixed effects analysis of variance was used in assessing the impact of laboratory and preservation method on gene expression values for the 12 samples hybridized at 2 independent laboratories (24 GeneChips). One center was found to be in violation of the tissue handling protocol. No significant effect was noted owing to preservation method, which ensured that our tissue handling protocols are working properly. There was a significant laboratory effect with respect to cRNA yield, though this effect did not impact sample quality. We conclude that use of consistent protocols for sample collection, RNA extraction, cDNA/cRNA synthesis, labeling, hybridization, platform, image acquisition, normalization, and expression summaries can yield consistent expression values. Moreover, evaluation of sample quality at various steps in the data acquisition process is an important component of a multicenter study to ensure all participating centers adhere to established protocols. PMID:19214110

Archer, Kellie J; Mas, Valeria R; O'Brien, Thomas R; Pfeiffer, Ruth; Lum, Nicole L; Fisher, Robert A

2009-03-01

271

Resonant Waveguide Grating Biosensor for Microarrays  

Microsoft Academic Search

\\u000a A microarray consists of an indexed series of micron-sized spots of biological specimens for biomolecular interaction analysis.\\u000a Microarray technologies present miniaturized and multiplexed approaches for sensitive and selective profiling of genes, proteins,\\u000a and\\/or small molecules. Concurrent with the increasing applications of microarrays is the continuous efforts in developing\\u000a novel detection systems for improving sensitivity and reliability in signal detection. This

Ye Fang

2010-01-01

272

Probing Biology with Small Molecule Microarrays (SMM)  

Microsoft Academic Search

In the continuous drive to increase screening throughput and reduce sample requirement, microarray-based\\u000a technologies have risen to the occasion. In the past 7 years, a number of new methodologies have\\u000a been developed for preparing small molecule microarrays from combinatorial and natural product libraries\\u000a with the goal of identifying new interactions or enzymatic activities. Recent advances and applications\\u000a of small molecule microarrays are

Nicolas Winssinger; Zbigniew Pianowski; Francois Debaene

273

Gene Expression Microarrays in Cancer Research  

Microsoft Academic Search

The advent of microarray technology has enabled scientists to simultaneously investigate the expression of thousands of genes.\\u000a This technology has been widely used in cancer research to better characterize cancer behaviors at mRNA level and to obtain\\u000a new insights into various stages of carcinogenesis. A microarray-based experiment generally involves three major components:\\u000a microarray manufacturing, sample processing, and data analysis, with

Jian Yan; Weikuan Gu

274

Analysis of gene expression profile of pancreatic carcinoma using cDNA microarray  

Microsoft Academic Search

AIM: To identify new diagnostic markers and drug targets, the gene expression profiles of pancreatic cancer were compared with that of adjacent normal tissues utilizing cDNA microarray analysis. METHODS: cDNA probes were prepared by labeling mRNA from samples of six pancreatic carcinoma tissues with Cy5- dUTP and mRNA from adjacent normal tissues with Cy3- dUTP respectively through reverse transcription. The

Zhi-Jun Tan; Xian-Gui Hu; Gui-Song Cao; Yan Tang

275

Revealing Global Regulatory Features of Mammalian Alternative Splicing Using a Quantitative Microarray Platform  

Microsoft Academic Search

We describe the application of a microarray platform, which combines information from exon body and splice-junction probes, to perform a quantitative analysis of tissue-specific alternative splicing (AS) for thousands of exons in mammalian cells. Through this system, we have analyzed global features of AS in major mouse tissues. The results provide numerous inferences for the functions of tissue-specific AS, insights

Qun Pan; Ofer Shai; Christine Misquitta; Wen Zhang; Arneet L. Saltzman; Naveed Mohammad; Tomas Babak; Henry Siu; Timothy R. Hughes; Quaid D. Morris; Brendan J. Frey; Benjamin J. Blencowe

2004-01-01

276

Protein Microarrays and Biomarkers of Infectious Disease  

PubMed Central

Protein microarrays are powerful tools that are widely used in systems biology research. For infectious diseases, proteome microarrays assembled from proteins of pathogens will play an increasingly important role in discovery of diagnostic markers, vaccines, and therapeutics. Distinct formats of protein microarrays have been developed for different applications, including abundance-based and function-based methods. Depending on the application, design issues should be considered, such as the need for multiplexing and label or label free detection methods. New developments, challenges, and future demands in infectious disease research will impact the application of protein microarrays for discovery and validation of biomarkers.

Natesan, Mohan; Ulrich, Robert G.

2010-01-01

277

Maize Gene Atlas Developed by RNA Sequencing and Comparative Evaluation of Transcriptomes Based on RNA Sequencing and Microarrays  

PubMed Central

Transcriptome analysis is a valuable tool for identification and characterization of genes and pathways underlying plant growth and development. We previously published a microarray-based maize gene atlas from the analysis of 60 unique spatially and temporally separated tissues from 11 maize organs [1]. To enhance the coverage and resolution of the maize gene atlas, we have analyzed 18 selected tissues representing five organs using RNA sequencing (RNA-Seq). For a direct comparison of the two methodologies, the same RNA samples originally used for our microarray-based atlas were evaluated using RNA-Seq. Both technologies produced similar transcriptome profiles as evident from high Pearson's correlation statistics ranging from 0.70 to 0.83, and from nearly identical clustering of the tissues. RNA-Seq provided enhanced coverage of the transcriptome, with 82.1% of the filtered maize genes detected as expressed in at least one tissue by RNA-Seq compared to only 56.5% detected by microarrays. Further, from the set of 465 maize genes that have been historically well characterized by mutant analysis, 427 show significant expression in at least one tissue by RNA-Seq compared to 390 by microarray analysis. RNA-Seq provided higher resolution for identifying tissue-specific expression as well as for distinguishing the expression profiles of closely related paralogs as compared to microarray-derived profiles. Co-expression analysis derived from the microarray and RNA-Seq data revealed that broadly similar networks result from both platforms, and that co-expression estimates are stable even when constructed from mixed data including both RNA-Seq and microarray expression data. The RNA-Seq information provides a useful complement to the microarray-based maize gene atlas and helps to further understand the dynamics of transcription during maize development.

Sekhon, Rajandeep S.; Briskine, Roman; Hirsch, Candice N.; Myers, Chad L.; Springer, Nathan M.; Buell, C. Robin; de Leon, Natalia; Kaeppler, Shawn M.

2013-01-01

278

2008 Microarray Research Group (MARG Survey): Sensing the State of Microarray Technology  

EPA Science Inventory

Over the past several years, the field of microarrays has grown and evolved drastically. In its continued efforts to track this evolution and transformation, the ABRF-MARG has once again conducted a survey of international microarray facilities and individual microarray users. Th...

279

Emphysema lung tissue gene expression profiling.  

PubMed

Emphysema occurs in a subgroup of patients with chronic obstructive pulmonary disease and patients with the genetic defect of alpha(1)-antitrypsin deficiency who have a smoking history of many years' duration. Emphysema is generally the result of a chronic and progressive destruction of the alveolar structures, which is believed to be driven by chronic inflammation, infections, oxidative stress, and an imbalance of protease and antiprotease activity. Here, we use microarray technology to characterize the gene expression profile of lung tissue samples obtained from patients with advanced emphysema and that obtained from healthy subjects. We hypothesized that the gene expression profile of emphysema lung tissue is distinct when compared with the expression profile of normal lungs. We report that severely emphysematous tissue is characterized by a global decrease in gene expression and by an increased abundance of transcripts encoding proteins involved in inflammation, immune responses, and proteolysis. Whereas the gene expression profile is to some degree shared between "usual" emphysema and alpha(1)-antitrypsin deficiency-related emphysema, there are statistically significant differences in the modulation of groups of genes associated with protein and energy metabolism, and immune function, which allow distinction between these two emphysema types on the lung tissue level. PMID:15284076

Golpon, Heiko A; Coldren, Christopher D; Zamora, Martin R; Cosgrove, Gregory P; Moore, Mark D; Tuder, Rubin M; Geraci, Mark W; Voelkel, Norbert F

2004-07-29

280

A rapid and robust assay for detection of S-phase cell cycle progression in plant cells and tissues by using ethynyl deoxyuridine  

PubMed Central

Background Progress in plant cell cycle research is highly dependent on reliable methods for detection of cells replicating DNA. Frequency of S-phase cells (cells in DNA synthesis phase) is a basic parameter in studies on the control of cell division cycle and the developmental events of plant cells. Here we extend the microscopy and flow cytometry applications of the recently developed EdU (5-ethynyl-2'-deoxyuridine)-based S-phase assay to various plant species and tissues. We demonstrate that the presented protocols insure the improved preservation of cell and tissue structure and allow significant reduction in assay duration. In comparison with the frequently used detection of bromodeoxyuridine (BrdU) and tritiated-thymidine incorporation, this new methodology offers several advantages as we discuss here. Results Applications of EdU-based S-phase assay in microscopy and flow cytometry are presented by using cultured cells of alfalfa, Arabidopsis, grape, maize, rice and tobacco. We present the advantages of EdU assay as compared to BrdU-based replication assay and demonstrate that EdU assay -which does not require plant cell wall digestion or DNA denaturation steps, offers reduced assay duration and better preservation of cellular, nuclear and chromosomal morphologies. We have also shown that fast and efficient EdU assay can also be an efficient tool for dual parameter flow cytometry analysis and for quantitative assessment of replication in thick root samples of rice. Conclusions In plant cell cycle studies, EdU-based S-phase detection offers a superior alternative to the existing S-phase assays. EdU method is reliable, versatile, fast, simple and non-radioactive and it can be readily applied to many different plant systems.

2010-01-01

281

FGFR1 and WT1 are markers of human prostate cancer progression  

PubMed Central

Background Androgen-independent prostate adenocarcinomas are responsible for about 6% of overall cancer deaths in men. Methods We used DNA microarrays to identify genes related to the transition between androgen-dependent and androgen-independent stages in the LuCaP 23.1 xenograft model of prostate adenocarcinoma. The expression of the proteins encoded by these genes was then assessed by immunohistochemistry on tissue microarrays (TMA) including human prostate carcinoma samples issued from 85 patients who had undergone radical prostatectomy. Results FGFR1, TACC1 and WT1 gene expression levels were associated with the androgen-independent stage in xenografts and human prostate carcinoma samples. MART1 protein expression was correlated with pT2 tumor stages. Conclusion Our results suggest that each of these four genes may play a role, or at least reflect a stage of prostate carcinoma growth/development/progression.

Devilard, Elizabeth; Bladou, Franck; Ramuz, Olivier; Karsenty, Gilles; Dales, Jean-Philippe; Gravis, Gwenaelle; Nguyen, Catherine; Bertucci, Francois; Xerri, Luc; Birnbaum, Daniel

2006-01-01

282

Photoelectrochemical synthesis of DNA microarrays  

PubMed Central

Optical addressing of semiconductor electrodes represents a powerful technology that enables the independent and parallel control of a very large number of electrical phenomena at the solid-electrolyte interface. To date, it has been used in a wide range of applications including electrophoretic manipulation, biomolecule sensing, and stimulating networks of neurons. Here, we have adapted this approach for the parallel addressing of redox reactions, and report the construction of a DNA microarray synthesis platform based on semiconductor photoelectrochemistry (PEC). An amorphous silicon photoconductor is activated by an optical projection system to create virtual electrodes capable of electrochemically generating protons; these PEC-generated protons then cleave the acid-labile dimethoxytrityl protecting groups of DNA phosphoramidite synthesis reagents with the requisite spatial selectivity to generate DNA microarrays. Furthermore, a thin-film porous glass dramatically increases the amount of DNA synthesized per chip by over an order of magnitude versus uncoated glass. This platform demonstrates that PEC can be used toward combinatorial bio-polymer and small molecule synthesis.

Chow, Brian Y.; Emig, Christopher J.; Jacobson, Joseph M.

2009-01-01

283

DNA microarrays: translation of the genome from laboratory to clinic.  

PubMed

As the complete sequences of human and other mammalian genomes become available we are faced with the challenge of understanding how variation in sequence and gene expression contributes to neurological and psychiatric disorders. DNA microarrays, or DNA chips, provide the means to measure simultaneously where and when thousands of genes are expressed. Microarrays are changing the way that researchers approach work at the bench and have already yielded new insights into brain tumours, multiple sclerosis, acute neurological insults such as stroke and seizures, and schizophrenia. The study of disease-related changes in gene expression is the first step in the long process in translation of genome research to the clinic. Eventually, the changes observed in microarray studies will need to be independently confirmed and we wil need to understand how gene expression changes translate into functional effects at the cellular level in the nervous system. Progress in these studies will translate into array-based disease classification schemes and help optimise therapy for individual patients based on gene expression patterns or their genetic background. PMID:12849181

Geschwind, Daniel H

2003-05-01

284

Evaluating different methods of microarray data normalization  

Microsoft Academic Search

BACKGROUND: With the development of DNA hybridization microarray technologies, nowadays it is possible to simultaneously assess the expression levels of thousands to tens of thousands of genes. Quantitative comparison of microarrays uncovers distinct patterns of gene expression, which define different cellular phenotypes or cellular responses to drugs. Due to technical biases, normalization of the intensity levels is a pre-requisite to

André Fujita; João Ricardo Sato; Leonardo De Oliveira Rodrigues; Carlos Eduardo Ferreira; Mari Cleide Sogayar

2006-01-01

285

Biclustering Models for Structured Microarray Data  

Microsoft Academic Search

Microarrays have become a standard tool for investigating gene function and more complex microarray experiments are increasingly being conducted. For example, an experiment may involve samples from several groups or may investigate changes in gene expression over time for several subjects, leading to large three-way data sets. In response to this increase in data complexity, we propose some extensions to

Heather L. Turner; Trevor C. Bailey; Wojtek J. Krzanowski; Cheryl A. Hemingway

2005-01-01

286

Challenges in applying microarrays to environmental studies  

Microsoft Academic Search

Although DNA microarray technology has been used successfully to analyze global gene expression in pure cultures, it has not been rigorously tested and evaluated within the context of complex environmental samples. Adapting microarray hybridization for use in environmental studies faces several challenges associated with specificity, sensitivity and quantitation.

Jizhong Zhou; Dorothea K Thompson

2002-01-01

287

Microarrays Made Simple: "DNA Chips" Paper Activity  

ERIC Educational Resources Information Center

|DNA microarray technology is revolutionizing biological science. DNA microarrays (also called DNA chips) allow simultaneous screening of many genes for changes in expression between different cells. Now researchers can obtain information about genes in days or weeks that used to take months or years. The paper activity described in this article…

Barnard, Betsy

2006-01-01

288

The use and analysis of microarray data  

Microsoft Academic Search

Functional genomics is the study of gene function through the parallel expression measurements of genomes, most commonly using the technologies of microarrays and serial analysis of gene expression. Microarray usage in drug discovery is expanding, and its applications include basic research and target discovery, biomarker determination, pharmacology, toxicogenomics, target selectivity, development of prognostic tests and disease-subclass determination. This article reviews

Atul Butte

2002-01-01

289

Oligosaccharide microarrays to decipher the glyco code  

Microsoft Academic Search

The oligosaccharide moieties of glycoproteins, glycolipids, proteoglycans and polysaccharides are highly diverse, the reason for this diversity is not yet understood. Neoglycolipid technology allows the generation of oligosaccharide probes with lipid tags from desired sources and is showing promise as a basis for oligosaccharide microarrays. Such microarrays would allow surveys of glycomes and proteomes to be carried out, which would

Wengang Chai; Ten Feizi

2004-01-01

290

Linking microarray reporters with protein functions  

Microsoft Academic Search

Background: The analysis of microarray experiments requires accurate and up-to-date functional annotation of the microarray reporters to optimize the interpretation of the biological processes involved. Pathway visualization tools are used to connect gene expression data with existing biological pathways by using specific database identifiers that link reporters with elements in the pathways. Results: This paper proposes a novel method that

Stan Gaj; Arie Van Erk; Rachel I. M. Van Haaften; Chris T. A. Evelo

2007-01-01

291

Development of protein microarray technology to monitor biomarkers of rheumatoid arthritis disease  

Microsoft Academic Search

Most biological processes are mediated by complex networks of molecular interactions involving proteins. The analysis of protein expression in biological samples is especially important in the identification and monitoring of biomarkers for disease progression and therapeutic endpoints. In this paper, the development of a protein microarray format for multiplexed quantitative analysis of several potential markers for rheumatoid arthritis (RA) is

T. Urbanowska; S. Mangialaio; C. Hartmann; F. Legay

2003-01-01

292

DNA Microarray Data Analysis and Regression Modeling for Genetic Expression Profiling  

Microsoft Academic Search

We report on our studies in large-scale gene expression proling using DNA microarray data.The problem of molecular phenotyping { linking observed genetic expression proles to identiedphysiological or clinical states and outcomes { is one of simply critical importance for improvedunderstanding of disease progression and for improved therapies. Our main application here isin breast cancer, where interest lies in identifying characteristics

Mike West; Joseph R. Nevins; Jeffrey R Marks; Rainer Spang; Carrie Blanchette; Harry Zuzan

2000-01-01

293

An experiential analysis of microarray time series data of cancer metastasis using XMAS  

Microsoft Academic Search

Time series microarray analysis provides an invaluable insight into genetic progression of biological processes such as tumor metastasis. Many algorithms sustain statistical analysis which limits user interaction. We use XMAS to extract knowledge from datasets which increases human-computer synergy, thus providing increased analysis experience. Cancer Metastasis involves complex biological pathway information. The domain knowledge to deciphering these complex data can

A Azariah Samuel; M Xavier Suresh; M Vaishnavi Devi; Kumari Radha

2011-01-01

294

Post-analysis follow-up and validation of microarray experiments  

Microsoft Academic Search

Measurement of gene-expression profiles using microarray technology is becoming increasingly popular among the biomedical research community. Although there has been great progress in this field, investigators are still confronted with a difficult question after completing their experiments: how to validate the large data sets that are generated? This review summarizes current approaches to verifying global expression results, discusses the caveats

Rodrigo F. Chuaqui; Robert F. Bonner; Carolyn J. M. Best; John W. Gillespie; Michael J. Flaig; Stephen M. Hewitt; John L. Phillips; David B. Krizman; Michael A. Tangrea; Mamoun Ahram; W. Marston Linehan; Vladimir Knezevic; Michael R. Emmert-Buck

2002-01-01

295

Effect of fluidic transport on the reaction kinetics in lectin microarrays  

Microsoft Academic Search

Lectins are the proteins which can distinguish glycosylation patterns. They are frequently used as biomarkers for progressions of several diseases including cancer. As the lectin microarray based prognosis devices miniaturize the process of glycoprofiling, it is anticipated that their performance can be augmented by integration with microfluidic framework. This is analogous to microfluidics based DNA arrays. However, unlike small oligonucleotide

Bibhas Roy; Tamal Das; Tapas K. Maiti; Suman Chakraborty

2011-01-01

296

SOXs in human prostate cancer: implication as progression and prognosis factors  

PubMed Central

Background SOX genes play an important role in a number of developmental processes. Potential roles of SOXs have been demonstrated in various neoplastic tissues as tumor suppressors or promoters depending on tumor status and types. The aim of this study was to investigate the involvement of SOXs in the progression and prognosis of human prostate cancer (PCa). Methods The gene expression changes of SOXs in human PCa tissues compared with non-cancerous prostate tissues was detected using gene expression microarray, and confirmed by real-time quantitative reverse transcriptase-polymerase chain reaction (QRT-PCR) analysis and immunohositochemistry. The roles of these genes in castration resistance were investigated in LNCaP xenograft model of PCa. Results The microarray analysis identified three genes (SOX7, SOX9 and SOX10) of SOX family that were significantly dis-regulated in common among four PCa specimens. Consistent with the results of the microarray, differential mRNA and protein levels of three selected genes were found in PCa tissues by QRT-PCR analysis and immunohistochemistry. Additionally, we found that the immunohistochemical staining scores of SOX7 in PCa tissues with higher serum PSA level (P?=?0.02) and metastasis (P?=?0.03) were significantly lower than those with lower serum PSA level and without metastasis; the increased SOX9 protein expression was frequently found in PCa tissues with higher Gleason score (P?=?0.02) and higher clinical stage (P?tissues with higher serum PSA levels (P?=?0.03) and advanced pathological stage (P?=?0.01). Moreover, both univariate and multivariate analyses showed that the down-regulation of SOX7 and the up-regulation of SOX9 were independent predictors of shorter biochemical recurrence-free survival. Furthermore, we discovered that SOX7 was significantly down-regulated and SOX9 was significantly up-regulated during the progression to castration resistance. Conclusions Our data offer the convince evidence that the dis-regulation of SOX7, SOX9 and SOX10 may be associated with the aggressive progression of PCa. SOX7 and SOX9 may be potential markers for prognosis in PCa patients. Interestingly, the down-regulation of SOX7 and the up-regulation of SOX9 may be important mechanisms for castration-resistant progression of PCa.

2012-01-01

297

Two-laser, large-field hyperspectral microarray scanner for the analysis of multicolor microarrays.  

PubMed

We describe the development and operation of a two-laser, large-field hyperspectral scanner for analysis of multicolor genotyping microarrays. In contrast to confocal microarray scanners, in which wavelength selectivity is obtained by positioning band-pass filters in front of a photomultiplier detector, hyperspectral microarray scanners collect the complete visible emission spectrum from the labeled microarrays. Hyperspectral scanning permits discrimination of multiple spectrally overlapping fluorescent labels with minimal use of optical filters, thus offering important advantages over standard filter-based multicolor microarray scanners. The scanner uses two-sided oblique line illumination of microarrays. Two lasers are used for the excitation of dyes in the visible and near-infrared spectral regions. The hyperspectral scanner was evaluated with commercially available two-color calibration slides and with in-house-printed four-color microarrays containing dyes with spectral properties similar to their commercial genotyping array counterparts. PMID:18808153

Erfurth, Florian; Tretyakov, Alexander; Nyuyki, Berla; Mrotzek, Grit; Schmidt, Wolf-Dieter; Fassler, Dieter; Saluz, Hans Peter

2008-09-23

298

Differentiation of the Seven Major Lyssavirus Species by Oligonucleotide Microarray  

PubMed Central

An oligonucleotide microarray, LyssaChip, has been developed and verified as a highly specific diagnostic tool for differentiation of the 7 major lyssavirus species. As with conventional typing microarray methods, the LyssaChip relies on sequence differences in the 371-nucleotide region coding for the nucleoprotein. This region was amplified using nested reverse transcription-PCR primers that bind to the 7 major lyssaviruses. The LyssaChip includes 57 pairs of species typing and corresponding control oligonucleotide probes (oligoprobes) immobilized on glass slides, and it can analyze 12 samples on a single slide within 8 h. Analysis of 111 clinical brain specimens (65 from animals with suspected rabies submitted to the laboratory and 46 of butchered dog brain tissues collected from restaurants) showed that the chip method was 100% sensitive and highly consistent with the “gold standard,” a fluorescent antibody test (FAT). The chip method could detect rabies virus in highly decayed brain tissues, whereas the FAT did not, and therefore the chip test may be more applicable to highly decayed brain tissues than the FAT. LyssaChip may provide a convenient and inexpensive alternative for diagnosis and differentiation of rabies and rabies-related diseases.

Xi, Jin; Guo, Huancheng; Feng, Ye; Xu, Yunbin; Shao, Mingfu; Su, Nan; Wan, Jiayu; Li, Jiping

2012-01-01

299

Differentially profiling the low-expression transcriptomes of human hepatoma using a novel SSH/microarray approach  

PubMed Central

Background The main limitation in performing genome-wide gene-expression profiling is the assay of low-expression genes. Approaches with high throughput and high sensitivity for assaying low-expression transcripts are urgently needed for functional genomic studies. Combination of the suppressive subtractive hybridization (SSH) and cDNA microarray techniques using the subtracted cDNA clones as probes printed on chips has greatly improved the efficiency for fishing out the differentially expressed clones and has been used before. However, it remains tedious and inefficient sequencing works for identifying genes including the great number of redundancy in the subtracted amplicons, and sacrifices the original advantages of high sensitivity of SSH in profiling low-expression transcriptomes. Results We modified the previous combination of SSH and microarray methods by directly using the subtracted amplicons as targets to hybridize the pre-made cDNA microarrays (named as "SSH/microarray"). mRNA prepared from three pairs of hepatoma and non-hepatoma liver tissues was subjected to the SSH/microarray assays, as well as directly to regular cDNA microarray assays for comparison. As compared to the original SSH and microarray combination assays, the modified SSH/microarray assays allowed for much easier inspection of the subtraction efficiency and identification of genes in the subtracted amplicons without tedious and inefficient sequencing work. On the other hand, 5015 of the 9376 genes originally filtered out by the regular cDNA microarray assays because of low expression became analyzable by the SSH/microarray assays. Moreover, the SSH/microarray assays detected about ten times more (701 vs. 69) HCC differentially expressed genes (at least a two-fold difference and P < 0.01), particularly for those with rare transcripts, than did the regular cDNA microarray assays. The differential expression was validated in 9 randomly selected genes in 18 pairs of hepatoma/non-hepatoma liver tissues using quantitative RT-PCR. The SSH/microarray approaches resulted in identifying many differentially expressed genes implicated in the regulation of cell cycle, cell death, signal transduction and cell morphogenesis, suggesting the involvement of multi-biological processes in hepato-carcinogenesis. Conclusion The modified SSH/microarray approach is a simple but high-sensitive and high-efficient tool for differentially profiling the low-expression transcriptomes. It is most adequate for applying to functional genomic studies.

Pan, Yi-Shin; Lee, Yun-Shien; Lee, Yung-Lin; Lee, Wei-Chen; Hsieh, Sen-Yung

2006-01-01

300

Seasonal dynamics of harmful algae in outer Oslofjorden monitored by microarray, qPCR, and microscopy.  

PubMed

Monitoring of marine microalgae is important to predict and manage harmful algal blooms. Microarray Detection of Toxic ALgae (MIDTAL) is an FP7-funded EU project aiming to establish a multi-species microarray as a tool to aid monitoring agencies. We tested the suitability of different prototype versions of the MIDTAL microarray for the monthly monitoring of a sampling station in outer Oslofjorden during a 1-year period. Microarray data from two different versions of the MIDTAL chip were compared to results from cell counts (several species) and quantitative real-time PCR (qPCR; only Pseudochattonella spp.). While results from generation 2.5 microarrays exhibited a high number of false positive signals, generation 3.3 microarray data generally correlated with microscopy and qPCR data, with three important limitations: (1) Pseudo-nitzschia cells were not reliably detected, possibly because cells were not sufficiently retained during filtration or lysed during the extraction, and because of low sensitivity of the probes; (2) in the case of samples with high concentrations of non-target species, the sensitivity of the arrays was decreased; (3) one occurrence of Alexandrium pseudogonyaulax was not detected due to a 1-bp mismatch with the genus probe represented on the microarray. In spite of these shortcomings our data demonstrate the overall progress made and the potential of the MIDTAL array. The case of Pseudochattonella - where two morphologically similar species impossible to separate by light microscopy were distinguished - in particular, underlines the added value of molecular methods such as microarrays in routine phytoplankton monitoring. PMID:23325054

Dittami, Simon M; Hostyeva, Vladyslava; Egge, Elianne Sirnæs; Kegel, Jessica U; Eikrem, Wenche; Edvardsen, Bente

2013-01-17

301

Genome-wide estimation of transcript concentrations from spotted cDNA microarray data  

Microsoft Academic Search

A method providing absolute transcript concen- trations from spotted microarray intensity data is presented. Number of transcripts per mg total RNA, mRNA or per cell, are obtained for each gene, enabling comparisons of transcript levels within and between tissues. The method is based on Bayesian statistical modelling incorporating avail- able information about the experiment from target preparation to image analysis,

Arnoldo Frigessi; Wiel van de M. A; Marit Holden; Debbie H. Svendsrud; Ingrid K. Glad; Heidi Lyng

2005-01-01

302

Probe-level analysis of expression microarrays characterizes isoform-specific degradation during mouse oocyte maturation  

Microsoft Academic Search

BACKGROUND: Gene expression microarrays have provided many insights into changes in gene expression patterns between different tissue types, developmental stages, and disease states. Analyses of these data focused primarily measuring the relative abundance of transcripts of a gene, while treating most or all transcript isoforms as equivalent. Differences in the selection between transcript isoforms can, however, represent critical changes to

Jesse Salisbury; Keith W. Hutchison; Karen Wigglesworth; John J. Eppig; Joel H. Graber

2009-01-01

303

Probe-Level Analysis of Expression Microarrays Characterizes Isoform-Specific Degradation during Mouse Oocyte Maturation  

Microsoft Academic Search

BackgroundGene expression microarrays have provided many insights into changes in gene expression patterns between different tissue types, developmental stages, and disease states. Analyses of these data focused primarily measuring the relative abundance of transcripts of a gene, while treating most or all transcript isoforms as equivalent. Differences in the selection between transcript isoforms can, however, represent critical changes to either

Jesse Salisbury; Keith W. Hutchison; Karen Wigglesworth; John J. Eppig; Joel H. Graber; Thomas Preiss

2009-01-01

304

A comparative review of statistical methods for discovering differentially expressed genes in replicated microarray experiments  

Microsoft Academic Search

Motivation: A common task in analyzing microarray data is to determine which genes are differentially expressed across two kinds of tissue samples or samples obtained under two experimental conditions. Recently several statistical methods have been proposed to accomplish this goal when there are replicated samples under each condition. However, it may not be clear how these methods compare with each

Wei Pan

2002-01-01

305

Microarray Analysis of Gene Expression Profiles in Cells Transfected With Nonviral Vectors  

Microsoft Academic Search

Inefficient gene delivery is a critical factor limiting the use of nonviral methods in therapeutic applications including gene therapy and tissue engineering. There have been few efforts to understand or engineer the molecular signaling pathways that dictate the efficacy of gene transfer. Microarray analysis was used to determine endogenous gene expression profiles modulated during nonviral gene transfer. Nonviral DNA lipoplexes

Sarah A Plautz; Gina Boanca; Jean-Jack M Riethoven; Angela K Pannier

2011-01-01

306

Fish and chips: Various methodologies demonstrate utility of a 16,006-gene salmonid microarray  

PubMed Central

Background We have developed and fabricated a salmonid microarray containing cDNAs representing 16,006 genes. The genes spotted on the array have been stringently selected from Atlantic salmon and rainbow trout expressed sequence tag (EST) databases. The EST databases presently contain over 300,000 sequences from over 175 salmonid cDNA libraries derived from a wide variety of tissues and different developmental stages. In order to evaluate the utility of the microarray, a number of hybridization techniques and screening methods have been developed and tested. Results We have analyzed and evaluated the utility of a microarray containing 16,006 (16K) salmonid cDNAs in a variety of potential experimental settings. We quantified the amount of transcriptome binding that occurred in cross-species, organ complexity and intraspecific variation hybridization studies. We also developed a methodology to rapidly identify and confirm the contents of a bacterial artificial chromosome (BAC) library containing Atlantic salmon genomic DNA. Conclusion We validate and demonstrate the usefulness of the 16K microarray over a wide range of teleosts, even for transcriptome targets from species distantly related to salmonids. We show the potential of the use of the microarray in a variety of experimental settings through hybridization studies that examine the binding of targets derived from different organs and tissues. Intraspecific variation in transcriptome expression is evaluated and discussed. Finally, BAC hybridizations are demonstrated as a rapid and accurate means to identify gene content.

von Schalburg, Kristian R; Rise, Matthew L; Cooper, Glenn A; Brown, Gordon D; Gibbs, A Ross; Nelson, Colleen C; Davidson, William S; Koop, Ben F

2005-01-01

307

MARS: Microarray analysis, retrieval, and storage system  

PubMed Central

Background Microarray analysis has become a widely used technique for the study of gene-expression patterns on a genomic scale. As more and more laboratories are adopting microarray technology, there is a need for powerful and easy to use microarray databases facilitating array fabrication, labeling, hybridization, and data analysis. The wealth of data generated by this high throughput approach renders adequate database and analysis tools crucial for the pursuit of insights into the transcriptomic behavior of cells. Results MARS (Microarray Analysis and Retrieval System) provides a comprehensive MIAME supportive suite for storing, retrieving, and analyzing multi color microarray data. The system comprises a laboratory information management system (LIMS), a quality control management, as well as a sophisticated user management system. MARS is fully integrated into an analytical pipeline of microarray image analysis, normalization, gene expression clustering, and mapping of gene expression data onto biological pathways. The incorporation of ontologies and the use of MAGE-ML enables an export of studies stored in MARS to public repositories and other databases accepting these documents. Conclusion We have developed an integrated system tailored to serve the specific needs of microarray based research projects using a unique fusion of Web based and standalone applications connected to the latest J2EE application server technology. The presented system is freely available for academic and non-profit institutions. More information can be found at .

Maurer, Michael; Molidor, Robert; Sturn, Alexander; Hartler, Juergen; Hackl, Hubert; Stocker, Gernot; Prokesch, Andreas; Scheideler, Marcel; Trajanoski, Zlatko

2005-01-01

308

DNA Microarrays in Herbal Drug Research  

PubMed Central

Natural products are gaining increased applications in drug discovery and development. Being chemically diverse they are able to modulate several targets simultaneously in a complex system. Analysis of gene expression becomes necessary for better understanding of molecular mechanisms. Conventional strategies for expression profiling are optimized for single gene analysis. DNA microarrays serve as suitable high throughput tool for simultaneous analysis of multiple genes. Major practical applicability of DNA microarrays remains in DNA mutation and polymorphism analysis. This review highlights applications of DNA microarrays in pharmacodynamics, pharmacogenomics, toxicogenomics and quality control of herbal drugs and extracts.

Chavan, Preeti; Joshi, Kalpana; Patwardhan, Bhushan

2006-01-01

309

Microarray techniques in pathology: tool or toy?  

PubMed Central

Microarray technology allows the simultaneous analysis of up to thousands of different genes in histological or cytological specimens. Although microarray technology has so far mainly been applied in the research setting, its clinical application in pathology is expected in the foreseeable future. This paper presents an overview of the technical “ins and outs” of microarray technology, and discusses several putative applications in diagnostic pathology, which include tumour classification, the prediction of responses to certain chemotherapeutical or hormonal agents, the biological staging of tumours, the risk assessment of premalignant lesions, and the detection of microorganisms.

Snijders, A M; Meijer, G A; Brakenhoff, R H; van den Brule, A J C; van Diest, P J

2000-01-01

310

DNA microarrays in the clinic: infectious diseases.  

PubMed

We argue that the most-promising area of clinical application of microarrays in the foreseeable future is the diagnostics and monitoring of infectious diseases. Microarrays for the detection and characterization of human pathogens have already found their way into clinical practice in some countries. After discussing the persistent, yet often underestimated, importance of infectious diseases for public health, we consider the technologies that are best suited for the detection and clinical investigation of pathogens. Clinical application of microarray technologies for the detection of mycobacteria, Bacillus anthracis, HIV, hepatitis and influenza viruses, and other major pathogens, as well as the analysis of their drug-resistance patterns, illustrate our main thesis. PMID:18536036

Mikhailovich, Vladimir; Gryadunov, Dmitry; Kolchinsky, Alexander; Makarov, Alexander A; Zasedatelev, Alexander

2008-07-01

311

Enhancing results of microarray hybridizations through microagitation.  

PubMed

Protein and DNA microarrays have become a standard tool in proteomics/genomics research. In order to guarantee fast and reproducible hybridization results, the diffusion limit must be overcome. Surface acoustic wave (SAW) micro-agitation chips efficiently agitate the smallest sample volumes (down to 10 microL and below) without introducing any dead volume. The advantages are reduced reaction time, increased signal-to-noise ratio, improved homogeneity across the microarray, and better slide-to-slide reproducibility. The SAW micromixer chips are the heart of the Advalytix Array-Booster, which is compatible with all microarrays based on the microscope slide format. PMID:13678150

Toegl, Andreas; Kirchner, Roland; Gauer, Christoph; Wixforth, Achim

2003-09-01

312

On partial least squares dimension reduction for microarray-based classification: a simulation study  

Microsoft Academic Search

Abstract In microarray tumor tissue classi'cation studies, the expressions of thousands of genes (vari- ables) are simultaneously measured across a few tissue samples. Standard statistical methodolo- gies in classi'cation do not work well when the dimension, p, is greater than the sample size, N . One approach to classi'cation problems, when pN , is to 'rst apply a dimension reduc-

Danh V. Nguyen; D. M. David M. Rocke

2004-01-01

313

Progressive lung cancer determined by expression profiling and transcriptional regulation.  

PubMed

Clinically, our ability to predict disease outcome for patients with early stage lung cancer is currently poor. To address this issue, tumour specimens were collected at surgery from non-small cell lung cancer (NSCLC) patients as part of the European Early Lung Cancer (EUELC) consortium. The patients were followed-up for three years post-surgery and patients who suffered progressive disease (PD, tumour recurrence, metastasis or a second primary) or remained disease-free (DF) during follow-up were identified. RNA from both tumour and adjacent-normal lung tissue was extracted from patients and subjected to microarray expression profiling. These samples included 36 adenocarcinomas and 23 squamous cell carcinomas from both PD and DF patients. The microarray data was subject to a series of systematic bioinformatics analyses at gene, network and transcription factor levels. The focus of these analyses was 2-fold: firstly to determine whether there were specific biomarkers capable of differentiating between PD and DF patients, and secondly, to identify molecular networks which may contribute to the progressive tumour phenotype. The experimental design and analyses performed permitted the clear differentiation between PD and DF patients using a set of biomarkers implicated in neuroendocrine signalling and allowed the inference of a set of transcription factors whose activity may differ according to disease outcome. Potential links between the biomarkers, the transcription factors and the genes p21/CDKN1A and Myc, which have previously been implicated in NSCLC development, were revealed by a combination of pathway analysis and microarray meta-analysis. These findings suggest that neuroendocrine-related genes, potentially driven through p21/CDKN1A and Myc, are closely linked to whether or not a NSCLC patient will have poor clinical outcome. PMID:22469662

Han, Namshik; Dol, Zulkifli; Vasieva, Olga; Hyde, Russell; Liloglou, Triantafillos; Raji, Olaide; Brambilla, Elisabeth; Brambilla, Christian; Martinet, Yves; Sozzi, Gabriella; Risch, Angela; Montuenga, Luis M; Brass, Andy; Field, John K

2012-03-28

314

The Stanford Microarray Database accommodates additional microarray platforms and data formats  

Microsoft Academic Search

The Stanford Microarray Database (SMD) (http:\\/\\/ smd.stanford.edu) is a research tool for hundreds of Stanford researchers and their collaborators. Inaddition,SMDfunctionsasaresourcefortheentire biological research community by providing unrest- ricted access to microarray data published by SMD users and by disseminating its source code. In addi- tion to storing GenePix (Axon Instruments) and ScanAlyze output from spotted microarrays, SMD has recently added the

Catherine A. Ball; Ihab A. B. Awad; Janos Demeter; Jeremy Gollub; Joan M. Hebert; Tina Hernandez-boussard; Heng Jin; John C. Matese; Michael Nitzberg; Farrell Wymore; Zachariah K. Zachariah; Patrick O. Brown; Gavin Sherlock

2005-01-01

315

The MicroArray Quality Control (MAQC) Project and Cross-Platform Analysis of Microarray Data  

Microsoft Academic Search

\\u000a As a powerful tool for genome-wide gene expression analysis, DNA microarray technology is widely used in biomedical research.\\u000a One important application of microarrays is to identify differentially expressed genes (DEGs) between two distinct biological\\u000a conditions, e.g. disease versus normal or treatment versus control, so that the underlying molecular mechanism differentiating\\u000a the two conditions maybe revealed. Mechanistic interpretation of microarray results

Zhining Wen; Zhenqiang Su; Jie Liu; Baitang Ning; Lei Guo; Weida Tong; Leming Shi

316

Microarray validation: factors influencing correlation between oligonucleotide microarrays and real-time PCR  

Microsoft Academic Search

Quantitative real-time PCR (qPCR) is a commonly used validation tool for confirming gene expression results obtained from\\u000a microarray analysis; however, microarray and qPCR data often result in disagreement. The current study assesses factors contributing\\u000a to the correlation between these methods in five separate experiments employing two-color 60-mer oligonucleotide microarrays\\u000a and qPCR using SYBR green. Overall, significant correlation was observed between

Jeanine S. Morey; James C. Ryan; Frances M. Van Dolah

2006-01-01

317

A novel surface modification approach for protein and cell microarrays  

NASA Astrophysics Data System (ADS)

Tissue engineering and stem cell technologies have led to a rapidly increasing interest in the control of the behavior of mammalian cells growing on tissue culture substrates. Multifunctional polymer coatings can assist research in this area in many ways, for example, by providing low non-specific protein adsorption properties and reactive functional groups at the surface. The latter can be used for immobilization of specific biological factors that influence cell behavior. In this study, glass slides were coated with copolymers of glycidyl methacrylate (GMA) and poly(ethylene glycol) methacrylate (PEGMA). The coatings were prepared by three different methods based on dip and spin coating as well as polymer grafting procedures. Coatings were characterized by X-ray photoelectron spectroscopy, surface sensitive infrared spectroscopy, ellipsometry and contact angle measurements. A fluorescently labelled protein was deposited onto reactive coatings using a contact microarrayer. Printing of a model protein (fluorescein labeled bovine serum albumin) was performed at different protein concentrations, pH, temperature, humidity and using different micropins. The arraying of proteins was studied with a microarray scanner. Arrays printed at a protein concentration above 50 µg/mL prepared in pH 5 phosphate buffer at 10°C and 65% relative humidity gave the most favourable results in terms of the homogeneity of the printed spots and the fluorescence intensity.

Kurkuri, Mahaveer D.; Driever, Chantelle; Thissen, Helmut W.; Voelcker, Nicholas H.

2007-01-01

318

Contributions to Statistical Problems Related to Microarray Data  

ERIC Educational Resources Information Center

|Microarray is a high throughput technology to measure the gene expression. Analysis of microarray data brings many interesting and challenging problems. This thesis consists three studies related to microarray data. First, we propose a Bayesian model for microarray data and use Bayes Factors to identify differentially expressed genes. Second, we…

Hong, Feng

2009-01-01

319

RNA profiling of MS brain tissues.  

PubMed

Recently, the introduction of RNA profiling using microarray technology has helped to elucidate gene expression changes in diseased tissue samples from postmortem human brains. Especially, in the field of multiple sclerosis (MS) research, microarray-based RNA profiling has been applied in the hope to identify disease specific alterations. The lack of good biomarkers for diagnostic as well as for prognostic purposes, but also the need for new drug targets and for a better understanding of the pathophysiology, makes this technique a valuable tool. Different RNA profiling approaches have been used, addressing distinct scientific questions. MS brain tissue samples have been proven to be an appropriate source for RNA profiling to investigate molecular pathomechanisms. This work discusses the critical parameters for RNA profiling of MS brain tissues, and reviews the results obtained by microarray studies analyzing differential gene expression in MS brain tissues. PMID:18782500

Kinter, J; Zeis, T; Schaeren-Wiemers, N

2008-06-01

320

Protein Microarrays: Novel Developments and Applications  

PubMed Central

Protein microarray technology possesses some of the greatest potential for providing direct information on protein function and potential drug targets. For example, functional protein microarrays are ideal tools suited for the mapping of biological pathways. They can be used to study most major types of interactions and enzymatic activities that take place in biochemical pathways and have been used for the analysis of simultaneous multiple biomolecular interactions involving protein-protein, protein-lipid, protein-DNA and protein-small molecule interactions. Because of this unique ability to analyze many kinds of molecular interactions en masse, the requirement of very small sample amount and the potential to be miniaturized and automated, protein microarrays are extremely well suited for protein profiling, drug discovery, drug target identification and clinical prognosis and diagnosis. The aim of this review is to summarize the most recent developments in the production, applications and analysis of protein microarrays.

Berrade, Luis; Garcia, Angie E.

2011-01-01

321

Data processing and analysis for protein microarrays.  

PubMed

Protein microarrays are a high-throughput technology capable of generating large quantities of proteomics data. They can be used for general research or for clinical diagnostics. Bioinformatics and statistical analysis techniques are required for interpretation and reaching biologically relevant conclusions from raw data. We describe essential algorithms for processing protein microarray data, including spot-finding on slide images, Z score, and significance analysis of microarrays (SAM) calculations, as well as the concentration dependent analysis (CDA). We also describe available tools for protein microarray analysis, and provide a template for a step-by-step approach to performing an analysis centered on the CDA method. We conclude with a discussion of fundamental and practical issues and considerations. PMID:21370075

DeLuca, David S; Marina, Ovidiu; Ray, Surajit; Zhang, Guang Lan; Wu, Catherine J; Brusic, Vladimir

2011-01-01

322

Derivation of extracellular fluid volume fraction and equivalent dielectric constant of the cell membrane from dielectric properties of the human body. Part 2: A preliminary study for tracking the progression of surgical tissue injury  

Microsoft Academic Search

A study is conducted to determine whether the extracellular fluid (ECF) volume fraction and equivalent dielectric constant\\u000a of the cell membrane ?m, derived from the dielectric properties of the human body can track the progression of surgical tissue injury. Frequency-dependent\\u000a dielectric constants and electrical conductivities of body segments are obtained at surgical (trunk) and non-surgical sites\\u000a (arm and leg) from

T. Tatara; K. Tsuzaki

2000-01-01

323

Microarray scanner calibration curves: characteristics and implications  

Microsoft Academic Search

BACKGROUND: Microarray-based measurement of mRNA abundance assumes a linear relationship between the fluorescence intensity and the dye concentration. In reality, however, the calibration curve can be nonlinear. RESULTS: By scanning a microarray scanner calibration slide containing known concentrations of fluorescent dyes under 18 PMT gains, we were able to evaluate the differences in calibration characteristics of Cy5 and Cy3. First,

Leming M. Shi; Weida Tong; Zhenqiang Su; Tao Han; Jing Han; Raj K. Puri; Hong Fang; Felix W. Frueh; Federico M. Goodsaid; Lei Guo; William S. Branham; James J. Chen; Z. Alex Xu; Stephen C. Harris; Huixiao Hong; Qian Xie; Roger G Perkins; James C. Fuscoe

2005-01-01

324

Application of independent component analysis to microarrays  

PubMed Central

We apply linear and nonlinear independent component analysis (ICA) to project microarray data into statistically independent components that correspond to putative biological processes, and to cluster genes according to over- or under-expression in each component. We test the statistical significance of enrichment of gene annotations within clusters. ICA outperforms other leading methods, such as principal component analysis, k-means clustering and the Plaid model, in constructing functionally coherent clusters on microarray datasets from Saccharomyces cerevisiae, Caenorhabditis elegans and human.

Lee, Su-In; Batzoglou, Serafim

2003-01-01

325

A microarray approach for identifying mutated genes  

Microsoft Academic Search

This study was performed to evaluate if microarray technology can identify genes using their transcriptionally defective mutant alleles. Three barley (Hordeum vulgare L.) mutant strains, xantha-h57, xantha-f27 and xantha-g28, with mutations in the genes encoding the three subunits of the chlorophyll biosynthetic enzyme magnesium chelatase, were used in a reconstruction experiment. The mutation xantha-h57 prevents transcription of Xantha-h mRNA. Microarrays

Shakhira Zakhrabekova; C. Gamini Kannangara; Diter von Wettstein; Mats Hansson

2002-01-01

326

Intensity isotherms and distributions on oligonucleotide microarrays  

Microsoft Academic Search

We describe a physico-chemical model relating measured fluorescence intensities on oligonucleotide microarrays to the underlying specific target concentration in the hybridised solution via a hyperbolic isotherm response function. The model includes various chemical reactions occurring at the microarray surface and in bulk solution during hybridisation, including specific and non-specific hybridisation, and also the effects of probe-target dissociation during the post

Conrad J. Burden

2009-01-01

327

Integrative approaches for microarray data analysis.  

PubMed

Microarrays were one of the first technologies of the genomic revolution to gain widespread adoption, rapidly expanding from a cottage industry to the source of thousands of experimental results. They were one of the first assays for which data repositories and metadata were standardized and researchers were required by many journals to make published data publicly available. Microarrays provide high-throughput insights into the biological functions of genes and gene products; however, they also present a "curse of dimensionality," whereby the availability of many gene expression measurements in few samples make it challenging to distinguish noise from true biological signal. All of these factors argue for integrative approaches to microarray data analysis, which combine data from multiple experiments to increase sample size, avoid laboratory-specific bias, and enable new biological insights not possible from a single experiment. Here, we discuss several approaches to integrative microarray analysis for a diverse range of applications, including biomarker discovery, gene function and interaction prediction, and regulatory network inference. We also show how, by integrating large microarray compendia with diverse genomic data types, more nuanced biological hypotheses can be explored computationally. This chapter provides overviews and brief descriptions of each of these approaches to microarray integration. PMID:22130880

Waldron, Levi; Coller, Hilary A; Huttenhower, Curtis

2012-01-01

328

Associating phenotypes with molecular events: recent statistical advances and challenges underpinning microarray experiments.  

PubMed

Progress in mapping the genome and developments in array technologies have provided large amounts of information for delineating the roles of genes involved in complex diseases and quantitative traits. Since complex phenotypes are determined by a network of interrelated biological traits typically involving multiple inter-correlated genetic and environmental factors that interact in a hierarchical fashion, microarrays hold tremendous latent information. The analysis of microarray data is, however, still a bottleneck. In this paper, we review the recent advances in statistical analyses for associating phenotypes with molecular events underpinning microarray experiments. Classical statistical procedures to analyze phenotypes in genetics are reviewed first, followed by descriptions of the statistical procedures for linking molecular events to measured gene expression phenotypes (microarray-based gene expression) and observed phenotypes such as diseases status. These statistical procedures include (1) prior analysis, such as data quality controls, and normalization analyses for minimizing the effects of experimental artifacts and random noise; (2) gene selections and differentiation procedures based on inferential statistics for the class comparisons; (3) dynamic temporal patterns analysis through exploratory statistics such as unsupervised clustering and supervised classification and predictions; (4) assessing the reliability of microarray studies using real-time PCR and the reproducibility issues from many studies and multiple platforms. In addition, the post analysis to associate the discovered patterns of gene expression to pathway and functional analysis for selected genes are also considered in order to increase our understanding of interconnected gene processes. PMID:16292543

Liang, Yulan; Kelemen, Arpad

2005-11-15

329

Evaluation of protein kinase activities of cell lysates using peptide microarrays based on surface plasmon resonance imaging.  

PubMed

We developed a peptide microarray based on surface plasmon resonance (SPR) imaging for monitoring protein kinase activities in cell lysates. The substrate peptides of kinases were tethered to the microarray surface modified with a self-assembled monolayer of an alkanethiol with triethylene glycol terminus to create a low nonspecific binding surface. The phosphorylation of the substrate peptides immobilized on the surface was detected with the following phosphate specific binders by amplifying SPR signals: anti-phosphotyrosine antibody for tyrosine kinases and Phos-tag biotin (a phosphate-specific ligand with biotin tag) for serine/threonine kinases. Using the microarray, 9 kinds of protein kinases were evaluated as a pattern of phosphorylation of 26 kinds of substrate peptides. The pattern was unique for each protein kinase. The microarray could be used to evaluate the inhibitory activities of kinase inhibitors. The microarray was applied successfully for kinase activity monitoring of cell lysates. The chemical stimuli responsive activity changes of protein kinases in cell lysates could also be monitored by the peptide microarray. Thus, the peptide microarray based on SPR imaging would be applicable to cell-based drug discovery, diagnosis using tissue lysates, and biochemical studies to reveal signal transduction pathways. PMID:18191030

Mori, Takeshi; Inamori, Kazuki; Inoue, Yusuke; Han, Xiaoming; Yamanouchi, Go; Niidome, Takuro; Katayama, Yoshiki

2007-12-15

330

A Lateral Flow Protein Microarray for Rapid and Sensitive Antibody Assays  

PubMed Central

Protein microarrays are useful tools for highly multiplexed determination of presence or levels of clinically relevant biomarkers in human tissues and biofluids. However, such tools have thus far been restricted to laboratory environments. Here, we present a novel 384-plexed easy to use lateral flow protein microarray device capable of sensitive (<30 ng/mL) determination of antigen-specific antibodies in ten minutes of total assay time. Results were developed with gold nanobeads and could be recorded by a cell-phone camera or table top scanner. Excellent accuracy with an area under curve (AUC of 98% was achieved in comparison with an established glass microarray assay for 26 antigen-specific antibodies. We propose that the presented framework could find use in convenient and cost-efficient quality control of antibody production, as well as in providing a platform for multiplexed affinity-based assays in low-resource or mobile settings.

Gantelius, Jesper; Bass, Tarek; Sjoberg, Ronald; Nilsson, Peter; Andersson-Svahn, Helene

2011-01-01

331

Detection of gene amplification and deletion in high-grade gliomas using a genome DNA microarray (GenoSensor Array 300).  

PubMed

Glioblastoma is a rapidly growing tumor that accounts for more than 50% of all primary gliomas. Amplification of oncogenes and deletion of tumor suppressor genes frequently affects tumor progression. Thus, the goal of this study was to conduct a comprehensive analysis of gene aberrations of individual glioblastomas. A genome DNA microarray (GenoSensor Array 300), spotted with 287 target genes, was used to analyze resected tissue from 11 different high-grade gliomas. The average number of gene aberrations was 9.0 per case (WHO grade III) and 13.3 per case (WHO grade IV). EGFR was the most frequent amplified gene in this series (4 of 11 cases), and high-level amplification was also detected for EGFR, SAS/CDK4, and AKT1. A high frequency of deleted genes was observed in 6 of 11 cases (54.5%), including FGFR2, MTAP, and DMBT1. The detected gene aberrations were matched to the classical primary glioblastoma pathway in five of nine cases. We conclude that the GenoSensor Array 300 genomic DNA microarray is a useful method for the comprehensive identification of amplified and deleted genes in glioblastoma. PMID:14756442

Sasaki, Teruo; Arai, Hiroshi; Beppu, Takaaki; Ogasawara, Kuniaki

2003-01-01

332

Transcriptional profiling and biochemical analysis of mechanically induced cartilaginous tissues  

PubMed Central

Objective In order to characterize patterns of molecular expression that lead to cartilage formation in vivo in a post-natal setting, mRNA expression profiling was carried out across the timecourse of mechanically induced chondrogenesis. Methods Retired breeder Sprague-Dawley rats underwent production of a non-critical-size, transverse femoral osteotomy. Experimental animals (n=45) were subjected to bending stimulation (60° cyclic motion in the sagittal plane for 15 minutes/day) of the osteotomy gap beginning on post-operative day (POD) 10. Control animals (n=32) experienced continuous rigid fixation. mRNA isolated on POD 10, 17, 24, and 38 was analyzed using a microarray containing 608 genes involved in skeletal development, tissue differentiation, fracture healing, and mechanotransduction. The glycosaminoglycan (GAG) content of the stimulated tissues was compared to native articular cartilage as a means of assessing the progression of chondrogenic development of the tissues. Results The majority of the 100 genes that were differentially expressed were upregulated in response to mechanical stimulation. Many of these genes are associated with articular cartilage development and maintenance, diarthroidal joint development, cell adhesion, extracellular matrix synthesis, signal transduction, and skeletal development. Quantitative real-time PCR results were consistent with the microarray findings. The GAG content of the stimulated tissues increased over time and was no different from that of articular cartilage at POD 38. Conclusions The mechanical stimulation caused upregulation of genes principally involved in joint cavity morphogenesis and critical to articular cartilage function. Further study of this type of stimulation may identify key signaling events required for post-natal, hyaline cartilage formation.

Salisbury Palomares, Kristy T.; Gerstenfeld, Louis C.; Wigner, Nathan A.; Lenburg, Marc E.; Einhorn, Thomas A.; Morgan, Elise F.

2010-01-01

333

Evaluation of testicular toxicology of doxorubicin based on microarray analysis of testicular specific gene expression.  

PubMed

Testicular toxicity of chemical substances has been generally assessed by sperm properties and histology. However, the methods can provide only a few information of the mechanism of the toxicity. The aim of this study is to show a method that can evaluate an overview of testicular toxic mechanisms using a tissue-specific microarray and classification of genes using Medical Subject Headings (MeSH). Male ICR mice (6 weeks old) were treated with doxorubicin hydrochloride (0, 0.1, 0.3 mg/kg/time, three times per week) by subcutaneous injection for 6 weeks (until 11 weeks old). Six weeks after the final administration, tissue and blood samples were obtained. Testes were subjected to gene expression analysis using quantitative RT-PCR and cDNA microarray (testis2). To interpret the microarray data, genes were classified using MeSH related to the functions of testis and sperm. Doxorubicin (both 0.1 and 0.3 mg/kg group) induced a decrease in sperm normal morphology and mortality, daily sperm production, and the number of Sertoli cells in the seminiferous tubules. Quantitative RT-PCR and microarray analysis showed dysregulation of mRNA expression levels of genes related to Sertoli cells, germ cells and spermatogenesis. Analysis of microarray data showed a significant enrichment of a total of ten MeSH categories including Spermatogenesis, Sertoli cells, Germ cells and Male infertility. This article concluded that analysis using testicular specific microarray combined with MeSH showed a more comprehensive overview of testicular toxic mechanisms than existing methods; i.e., examination of sperm properties and the histological examinations. PMID:22008532

Takahashi, Hikari; Tainaka, Hitoshi; Umezawa, Masakazu; Takeda, Ken; Tanaka, Hiromitsu; Nishimune, Yoshitake; Oshio, Shigeru

2011-10-01

334

M3G: Maximum Margin Microarray Gridding  

PubMed Central

Background Complementary DNA (cDNA) microarrays are a well established technology for studying gene expression. A microarray image is obtained by laser scanning a hybridized cDNA microarray, which consists of thousands of spots representing chains of cDNA sequences, arranged in a two-dimensional array. The separation of the spots into distinct cells is widely known as microarray image gridding. Methods In this paper we propose M3G, a novel method for automatic gridding of cDNA microarray images based on the maximization of the margin between the rows and the columns of the spots. Initially the microarray image rotation is estimated and then a pre-processing algorithm is applied for a rough spot detection. In order to diminish the effect of artefacts, only a subset of the detected spots is selected by matching the distribution of the spot sizes to the normal distribution. Then, a set of grid lines is placed on the image in order to separate each pair of consecutive rows and columns of the selected spots. The optimal positioning of the lines is determined by maximizing the margin between these rows and columns by using a maximum margin linear classifier, effectively facilitating the localization of the spots. Results The experimental evaluation was based on a reference set of microarray images containing more than two million spots in total. The results show that M3G outperforms state of the art methods, demonstrating robustness in the presence of noise and artefacts. More than 98% of the spots reside completely inside their respective grid cells, whereas the mean distance between the spot center and the grid cell center is 1.2 pixels. Conclusions The proposed method performs highly accurate gridding in the presence of noise and artefacts, while taking into account the input image rotation. Thus, it provides the potential of achieving perfect gridding for the vast majority of the spots.

2010-01-01

335

Assessing affymetrix GeneChip microarray quality  

PubMed Central

Background Microarray technology has become a widely used tool in the biological sciences. Over the past decade, the number of users has grown exponentially, and with the number of applications and secondary data analyses rapidly increasing, we expect this rate to continue. Various initiatives such as the External RNA Control Consortium (ERCC) and the MicroArray Quality Control (MAQC) project have explored ways to provide standards for the technology. For microarrays to become generally accepted as a reliable technology, statistical methods for assessing quality will be an indispensable component; however, there remains a lack of consensus in both defining and measuring microarray quality. Results We begin by providing a precise definition of microarray quality and reviewing existing Affymetrix GeneChip quality metrics in light of this definition. We show that the best-performing metrics require multiple arrays to be assessed simultaneously. While such multi-array quality metrics are adequate for bench science, as microarrays begin to be used in clinical settings, single-array quality metrics will be indispensable. To this end, we define a single-array version of one of the best multi-array quality metrics and show that this metric performs as well as the best multi-array metrics. We then use this new quality metric to assess the quality of microarry data available via the Gene Expression Omnibus (GEO) using more than 22,000 Affymetrix HGU133a and HGU133plus2 arrays from 809 studies. Conclusions We find that approximately 10 percent of these publicly available arrays are of poor quality. Moreover, the quality of microarray measurements varies greatly from hybridization to hybridization, study to study, and lab to lab, with some experiments producing unusable data. Many of the concepts described here are applicable to other high-throughput technologies.

2011-01-01

336

Generalization of DNA microarray dispersion properties: microarray equivalent of t-distribution  

Microsoft Academic Search

BACKGROUND: DNA microarrays are a powerful technology that can provide a wealth of gene expression data for disease studies, drug development, and a wide scope of other investigations. Because of the large volume and inherent variability of DNA microarray data, many new statistical methods have been developed for evaluating the significance of the observed differences in gene expression. However, until

Jaroslav P Novak; Seon-Young Kim; Jun Xu; Olga Modlich; David J Volsky; David Honys; Joan L Slonczewski; Douglas A Bell; Fred R Blattner; Eduardo Blumwald; Marjan Boerma; Manuel Cosio; Zoran Gatalica; Marian Hajduch; Juan Hidalgo; Roderick R McInnes; Merrill C Miller III; Milena Penkowa; Michael S Rolph; Jordan Sottosanto; Rene St-Arnaud; Michael J Szego; David Twell; Charles Wang

2006-01-01

337

Transcriptional Profiling of Endocrine Cerebro-Osteodysplasia Using Microarray and Next-Generation Sequencing  

PubMed Central

Background Transcriptome profiling of patterns of RNA expression is a powerful approach to identify networks of genes that play a role in disease. To date, most mRNA profiling of tissues has been accomplished using microarrays, but next-generation sequencing can offer a richer and more comprehensive picture. Methodology/Principal Findings ECO is a rare multi-system developmental disorder caused by a homozygous mutation in ICK encoding intestinal cell kinase. We performed gene expression profiling using both cDNA microarrays and next-generation mRNA sequencing (mRNA-seq) of skin fibroblasts from ECO-affected subjects. We then validated a subset of differentially expressed transcripts identified by each method using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Finally, we used gene ontology (GO) to identify critical pathways and processes that were abnormal according to each technical platform. Methodologically, mRNA-seq identifies a much larger number of differentially expressed genes with much better correlation to qRT-PCR results than the microarray (r2?=?0.794 and 0.137, respectively). Biologically, cDNA microarray identified functional pathways focused on anatomical structure and development, while the mRNA-seq platform identified a higher proportion of genes involved in cell division and DNA replication pathways. Conclusions/Significance Transcriptome profiling with mRNA-seq had greater sensitivity, range and accuracy than the microarray. The two platforms generated different but complementary hypotheses for further evaluation.

Lahiry, Piya; Lee, Leo J.; Frey, Brendan J.; Rupar, C. Anthony; Siu, Victoria M.; Blencowe, Benjamin J.; Hegele, Robert A.

2011-01-01

338

Probe-Level Analysis of Expression Microarrays Characterizes Isoform-Specific Degradation during Mouse Oocyte Maturation  

PubMed Central

Background Gene expression microarrays have provided many insights into changes in gene expression patterns between different tissue types, developmental stages, and disease states. Analyses of these data focused primarily measuring the relative abundance of transcripts of a gene, while treating most or all transcript isoforms as equivalent. Differences in the selection between transcript isoforms can, however, represent critical changes to either the protein product or the posttranscriptional regulation of the transcript. Novel analyses on existing microarray data provide fresh insights and new interpretations into transcriptome-wide changes in expression. Methodology A probe-level analysis of existing gene expression arrays revealed differences in mRNA processing, primarily affecting the 3?-untranslated region. Working with the example of microarrays drawn from a transcriptionally silent period of mouse oocyte development, probe-level analysis (implemented here as rmodel) identified genes whose transcript isoforms have differing stabilities. Comparison of micorarrays measuring cDNA generated from oligo-dT and random primers revealed further differences in the polyadenylation status of some transcripts. Additional analysis provided evidence for sequence-targeted cleavage, including putative targeting sequences, as one mechanism of degradation for several hundred transcripts in the maturing oocyte. Conclusions The capability of probe-level analysis to elicit novel findings from existing expression microarray data was demonstrated. The characterization of differences in stability between transcript isoforms in maturing mouse oocytes provided some mechanistic details of degradation. Similar analysis of existing archives of expression microarray data will likely provide similar discoveries.

Salisbury, Jesse; Hutchison, Keith W.; Wigglesworth, Karen; Eppig, John J.; Graber, Joel H.

2009-01-01

339

A comparison of oligonucleotide and cDNA-based microarray systems.  

PubMed

Large-scale public data mining will become more common as public release of microarray data sets becomes a corequisite for publication. Therefore, there is an urgent need to clarify whether data from different microarray platforms are comparable. To assess the compatibility of microarray data, results were compared from the two main types of high-throughput microarray expression technologies, namely, an oligonucleotide-based and a cDNA-based platform, using RNA obtained from complex tissue (human colonic mucosa) of five individuals. From 715 sequence-verified genes represented on both platforms, 64% of the genes matched in "present" or "absent" calls made by both platforms. Calls were influenced by spurious signals caused by Alu repeats in cDNA clones, clone annotation errors, or matched probes that were designed to different regions of the gene; however, these factors could not completely account for the level of call discordance observed. Expression levels in sequence-verified, platform-overlapping genes were not related, as demonstrated by weakly positive rank order correlation. This study demonstrates that there is only moderate overlap in the results from the two array systems. This fact should be carefully considered when performing large-scale analyses on data originating from different microarray platforms. PMID:14645736

Mah, Nancy; Thelin, Anders; Lu, Tim; Nikolaus, Susanna; Kühbacher, Tanja; Gurbuz, Yesim; Eickhoff, Holger; Klöppel, Günther; Lehrach, Hans; Mellgård, Björn; Costello, Christine M; Schreiber, Stefan

2004-02-13

340

From combinatorial chemistry to chemical microarray.  

PubMed

Combinatorial chemistry was first applied to the generation of peptide arrays in 1984. Since then, the field of combinatorial chemistry has evolved rapidly into a new discipline. There is a great need for the development of methods to examine the proteome functionally at a global level. Using many of the techniques and instruments developed for DNA microarrays, chemical microarray methods have advanced significantly in the past three years. High-density chemical microarrays can now be synthesized in situ on glass slides or be printed through covalent linkage or non-specific adsorption to the surface of the solid-support with fully automatic arrayers. Microfabrication methods enable one to generate arrays of microsensors at the end of optical fibers or arrays of microwells on a flat surface. In conjunction with the one-bead one-compound combinatorial library method, chemical microarrays have proven to be very useful in lead identification and optimization. High-throughput protein expression systems, robust high-density protein, peptide and small-molecule microarray systems, and automatic mass spectrometers are critical tools for the field of functional proteomics. PMID:12023117

Lam, Kit S; Renil, Manat

2002-06-01

341

Microarray profiling reveals suppressed interferon stimulated gene program in fibroblasts from scleroderma-associated interstitial lung disease  

PubMed Central

Background Interstitial lung disease is a major cause of morbidity and mortality in systemic sclerosis (SSc), with insufficiently effective treatment options. Progression of pulmonary fibrosis involves expanding populations of fibroblasts, and the accumulation of extracellular matrix proteins. Characterisation of SSc lung fibroblast gene expression profiles underlying the fibrotic cell phenotype could enable a better understanding of the processes leading to the progressive build-up of scar tissue in the lungs. In this study we evaluate the transcriptomes of fibroblasts isolated from SSc lung biopsies at the time of diagnosis, compared with those from control lungs. Methods We used Affymetrix oligonucleotide microarrays to compare the gene expression profile of pulmonary fibroblasts cultured from 8 patients with pulmonary fibrosis associated with SSc (SSc-ILD), with those from control lung tissue peripheral to resected cancer (n=10). Fibroblast cultures from 3 patients with idiopathic pulmonary fibrosis (IPF) were included as a further comparison. Genes differentially expressed were identified using two separate analysis programs following a set of pre-determined criteria: only genes significant in both analyses were considered. Microarray expression data was verified by qRT-PCR and/or western blot analysis. Results A total of 843 genes were identified as differentially expressed in pulmonary fibroblasts from SSc-ILD and/or IPF compared to control lung, with a large overlap in the expression profiles of both diseases. We observed increased expression of a TGF-? response signature including fibrosis associated genes and myofibroblast markers, with marked heterogeneity across samples. Strongly suppressed expression of interferon stimulated genes, including antiviral, chemokine, and MHC class 1 genes, was uniformly observed in fibrotic fibroblasts. This expression profile includes key regulators and mediators of the interferon response, such as STAT1, and CXCL10, and was also independent of disease group. Conclusions This study identified a strongly suppressed interferon-stimulated gene program in fibroblasts from fibrotic lung. The data suggests that the repressed expression of interferon-stimulated genes may underpin critical aspects of the profibrotic fibroblast phenotype, identifying an area in pulmonary fibrosis that requires further investigation.

2013-01-01

342

Microarray for serotyping of Bartonella species  

PubMed Central

Background Bacteria of the genus Bartonella are responsible for a large variety of human and animal diseases. Serological typing of Bartonella is a method that can be used for differentiation and identification of Bartonella subspecies. Results We have developed a novel multiple antigenic microarray to serotype Bartonella strains and to select poly and monoclonal antibodies. It was validated using mouse polyclonal antibodies against 29 Bartonella strains. We then tested the microarray for serotyping of Bartonella strains and defining the profile of monoclonal antibodies. Bartonella strains gave a strong positive signal and all were correctly identified. Screening of monoclonal antibodies towards the Gro EL protein of B. clarridgeiae identified 3 groups of antibodies, which were observed with variable affinities against Bartonella strains. Conclusion We demonstrated that microarray of spotted bacteria can be a practical tool for serotyping of unidentified strains or species (and also for affinity determination) by polyclonal and monoclonal antibodies. This could be used in research and for identification of bacterial strains.

2007-01-01

343

Microarray technology--an intellectual property retrospective.  

PubMed

The recent sequencing of the human genome is a critical milestone that has provided a framework for the identification of thousands of novel potential drug targets and the common genetic factors that affect drug metabolism and toxicity. Microarrays represent a novel genetic platform which is being widely exploited to bridge the gap between gene sequence and function. Microarray technology has found broad use in the areas of disease diagnosis, pharmacogenomics and toxicogenomics, and many opportunities continue to be created in the marketplace. As the field matures and enters the clinical arena, we will witness further innovation in both the public and private sectors, which ultimately will improve the technology. However, the exercise of intellectual property rights in this area has shadowed the evolution of this technology. This report provides a retrospective review of microarrays, highlighting the key patents and litigation that have shaped the industry. PMID:12943468

Rouse, Richard; Hardiman, Gary

2003-09-01

344

Protein microarrays: technological aspects, applications and intellectual property.  

PubMed

Over the last decade, proteomics has undergone remarkable progress thanks to the technical advances made in the field. Improvements in the design of the protein microarrays, including more types of chemical groups for surface functionalization, new capture agents and novel detection strategies, among others, have allowed the detection of proteins in a robust, specific, sensitive, real time and high throughput manner. However, there are still problems that hinder the analysis of low abundance proteins or those present in complex samples. For this reason, the development of patents related to the features mentioned above has an important relevance. In this review, we focus on the study of recently approved patents that try to solve the existing problems. Thanks to them, it is expected that the identification of disease biomarkers can be made in a suitable and reliable way, and above all, biocompatible and environmentally friendly. PMID:23848276

Dasilva, Noelia; Díez, Paula; González-González, María; Matarraz, Sergio; J M Sayagués; Orfao, Alberto; Fuentes, Manuel

2013-08-01

345

Development of a Wireless High-Frequency Microarray Implant for Retinal Stimulation  

NASA Astrophysics Data System (ADS)

We have developed an electrical stimulator and diagnostic research microarray with wireless power and communications to facilitate spatial stimulation of retinal tissue. A third generation 32× 32 prototype of this retinal neural implant array has been developed. Integrated into the microarray is a functionally graded Ti/IrO2 microbump electrode system for interface with neural tissue with decreased impedance for stimulation. The microarray is designed for basic research to determine retinal tissue stimulation thresholds and spatial effects. The array is connected to a telemetry chip, which uses magnetic induction for wireless power with a digital overlay for communication. In our design, changes in the induced current in the telemetry coil are used to send information to the reading coil. Since the reading and telemetry coil are magnetically coupled, the current change can be sensed for bidirectional communication. Combined, this chip set provides a 1024 array that can stimulate neural tissue spatially, can sense neural signals spatially, and has wireless power and communication in a package of less than 2 mm size.

Auner, G. W.; You, R.; Siy, P.; McAllister, J. P.; Talukder, M.; Abrams, G. W.

346

What are microarrays teaching us about sleep?  

PubMed Central

Many fundamental questions about sleep remain unanswered. The presence of sleep across phyla suggests that it must serve a basic cellular and/or molecular function. Microarray studies, performed in several model systems, have identified classes of genes that are sleep-state regulated. This has led to the following concepts: first, a function of sleep is to maintain synaptic homeostasis; second, sleep is a stage of macromolecule biosynthesis; third, extending wakefulness leads to downregulation of several important metabolic pathways; and, fourth, extending wakefulness leads to endoplasmic reticulum stress. In human studies, microarrays are being applied to the identification of biomarkers for sleepiness and for the common debilitating condition of obstructive sleep apnea.

Mackiewicz, Miroslaw; Zimmerman, John E.; Shockley, Keith R.; Churchill, Gary A.; Pack, Allan I.

2010-01-01

347

Microarrays - A Key Technology for Glycobiology  

NASA Astrophysics Data System (ADS)

Carbohydrate chains of glycoproteins , glycolipids , and proteoglycans can mediate processes of biological and medical importance through their interactions with complementary proteins. The unraveling of these interactions is a priority therefore in biomedical sciences. Carbohydrate microarray technology is a new development at the frontiers of glycomics that has revolutionized the study of carbohydrate-protein interactions and the elucidation of their specificities in endogenous biological processes, immune defense mechanisms, and microbe-host interactions. In this chapter we briefly touch upon the principles of numerous platforms since the introduction of carbohydrate microarrays in 2002, and we highlight platforms that are beyond proof-of-concept, and have provided new biological information.

Liu, Yan; Feizi, Ten

348

Microarray ? US: a user-friendly graphical interface to Bioconductor tools that enables accurate microarray data analysis and expedites comprehensive functional analysis of microarray results  

PubMed Central

Background Microarray data analysis presents a significant challenge to researchers who are unable to use the powerful Bioconductor and its numerous tools due to their lack of knowledge of R language. Among the few existing software programs that offer a graphic user interface to Bioconductor packages, none have implemented a comprehensive strategy to address the accuracy and reliability issue of microarray data analysis due to the well known probe design problems associated with many widely used microarray chips. There is also a lack of tools that would expedite the functional analysis of microarray results. Findings We present Microarray ? US, an R-based graphical user interface that implements over a dozen popular Bioconductor packages to offer researchers a streamlined workflow for routine differential microarray expression data analysis without the need to learn R language. In order to enable a more accurate analysis and interpretation of microarray data, we incorporated the latest custom probe re-definition and re-annotation for Affymetrix and Illumina chips. A versatile microarray results output utility tool was also implemented for easy and fast generation of input files for over 20 of the most widely used functional analysis software programs. Conclusion Coupled with a well-designed user interface, Microarray ? US leverages cutting edge Bioconductor packages for researchers with no knowledge in R language. It also enables a more reliable and accurate microarray data analysis and expedites downstream functional analysis of microarray results.

2012-01-01

349

Combining Semantic Relations and DNA Microarray Data for Novel Hypotheses Generation  

Microsoft Academic Search

\\u000a Although microarray experiments have great potential to support progress in biomedical research, results are not easy to interpret.\\u000a Information about the functions and relations of relevant genes needs to be extracted from the vast biomedical literature.\\u000a A potential solution is to use computerized text analysis methods. Our proposal enhances these methods with semantic relations.\\u000a We describe an application that integrates

Dimitar Hristovski; Andrej Kastrin; Borut Peterlin; Thomas C. Rindflesch

350

ampliPHOX Colorimetric Detection on a DNA Microarray for Influenza  

PubMed Central

DNA microarrays have emerged as a powerful tool for pathogen detection.1-5 For instance, many examples of the ability to type and subtype influenza virus have been demonstrated.6-11 The identification and subtyping of influenza on DNA microarrays has applications in both public health and the clinic for early detection, rapid intervention, and minimizing the impact of an influenza pandemic. Traditional fluorescence is currently the most commonly used microarray detection method. However, as microarray technology progresses towards clinical use,1 replacing expensive instrumentation with low cost detection technology exhibiting similar performance characteristics to fluorescence will make microarray assays more attractive and cost-effective. The ampliPHOX colorimetric detection technology is intended for research applications, and has a limit of detection within one order of magnitude of traditional fluorescence11, with a main advantage being an approximate ten-fold lower instrument cost compared to the confocal microarray scanners required for fluorescence microarray detection. Another advantage is the compact size of the instrument which allows for portability and flexibility, unlike traditional fluorescence instruments. Because the polymerization technology is not as inherently linear as fluorescence detection, however, it is best suited for lower density microarray applications in which a yes/no answer for the presence of a certain sequence is desired, such as for pathogen detection arrays. Currently the maximum spot density compatible with ampliPHOX detection is ˜1800 spots/array. Because of the spot density limitations, higher density microarrays are not suitable for ampliPHOX detection. Here, we present ampliPHOX colorimetric detection technology as a method of signal amplification on a low density microarray developed for the detection and characterization of influenza viruses (FluChip). Although this protocol uses the FluChip (a DNA microarray) as one specific application of ampliPHOX detection, any microarray incorporating biotinylated target can be labeled and detected in a similar manner. The microarray design and biotinylation of the target to be captured are the responsibility of the user. Once the biotinylated target has been captured on the array, ampliPHOX detection can be performed by first tagging the array with a streptavidin-label conjugate (ampliTAG). Upon light exposure using the ampliPHOX Reader instrument, polymerization of a monomer solution (ampliPHY) occurs only in regions containing ampliTAG-labeled targets. The polymer formed can be subsequently stained with a non-toxic solution to improve visual contrast, followed by imaging and analysis using a simple software package (ampliVIEW). The entire FluChip assay from un-extracted sample to result can be performed in about 6 hours, and the ampliPHOX detection steps described above can be completed in about 30 min.

Moulton, Kevin R.; Taylor, Amber W.; Rowlen, Kathy L.; Dawson, Erica D.

2011-01-01

351

Development and validation of a flax (Linum usitatissimum L.) gene expression oligo microarray  

PubMed Central

Background Flax (Linum usitatissimum L.) has been cultivated for around 9,000 years and is therefore one of the oldest cultivated species. Today, flax is still grown for its oil (oil-flax or linseed cultivars) and its cellulose-rich fibres (fibre-flax cultivars) used for high-value linen garments and composite materials. Despite the wide industrial use of flax-derived products, and our actual understanding of the regulation of both wood fibre production and oil biosynthesis more information must be acquired in both domains. Recent advances in genomics are now providing opportunities to improve our fundamental knowledge of these complex processes. In this paper we report the development and validation of a high-density oligo microarray platform dedicated to gene expression analyses in flax. Results Nine different RNA samples obtained from flax inner- and outer-stems, seeds, leaves and roots were used to generate a collection of 1,066,481 ESTs by massive parallel pyrosequencing. Sequences were assembled into 59,626 unigenes and 48,021 sequences were selected for oligo design and high-density microarray (Nimblegen 385K) fabrication with eight, non-overlapping 25-mers oligos per unigene. 18 independent experiments were used to evaluate the hybridization quality, precision, specificity and accuracy and all results confirmed the high technical quality of our microarray platform. Cross-validation of microarray data was carried out using quantitative qRT-PCR. Nine target genes were selected on the basis of microarray results and reflected the whole range of fold change (both up-regulated and down-regulated genes in different samples). A statistically significant positive correlation was obtained comparing expression levels for each target gene across all biological replicates both in qRT-PCR and microarray results. Further experiments illustrated the capacity of our arrays to detect differential gene expression in a variety of flax tissues as well as between two contrasted flax varieties. Conclusion All results suggest that our high-density flax oligo-microarray platform can be used as a very sensitive tool for analyzing gene expression in a large variety of tissues as well as in different cultivars. Moreover, this highly reliable platform can also be used for the quantification of mRNA transcriptional profiling in different flax tissues.

2010-01-01

352

PRACTICAL STRATEGIES FOR PROCESSING AND ANALYZING SPOTTED OLIGONUCLEOTIDE MICROARRAY DATA  

EPA Science Inventory

Thoughtful data analysis is as important as experimental design, biological sample quality, and appropriate experimental procedures for making microarrays a useful supplement to traditional toxicology. In the present study, spotted oligonucleotide microarrays were used to profile...

353

Compression of cDNA and Inkjet Microarray Images.  

National Technical Information Service (NTIS)

Microarray image technology is a powerful tool for monitoring the expression of thousands of genes simultaneously. Each microarray experiment produces immense amounts of image data, and efficient storage and transmission requires compression that utilizes...

R. Jornsten B. Yu W. Wang K. Ramchandran

2002-01-01

354

Tissues from the irradiated dog/mouse archive  

SciTech Connect

The purpose of this project is to organize the databases/information and organize and move the tissues from the long-term dog (4,000 dogs) and mouse (over 30,000 mice) radiation experiments done at Argonne National Laboratory during the 1970's and 80's to Northwestern University. These studies were done with the intention of understanding the effects of exposure to radiation at a variety of different doses, dose-rates, and radiation qualities on end-points such as life-shortening, carcinogenesis, cause of death, shifts in disease incidence and other biological parameters. Organ and tissue samples from these animals including cancers, metastases and other significant degenerative and inflammatory lesions and those in a regular protocol of normal tissues were preserved in paraffin blocks, tissue impressions and sections and represent a great resource for the radiation biology community. These collections are particularly significant since these experiments are not likely to be repeated because of the extreme cost of monies and time for such large-scale animal studies. The long-term goal is to make these tissues and databases available to the wider scientific community so that questions such as tissue sensitivity, early and late effects, low dose and protracted dose responses of normal and tumor tissues, etc. can be examined and defined. Recent advances in biology particularly at the subcellular and molecular level now permit microarray-based gene expression array analyses from paraffin-embedded tissues (where RNA samples are significantly degraded), synchrotron-based studies of metal and other elemental distribution patterns in tissues, PCR-based analyses for mutation detection, and other similar approaches that were not available when the long¬ term animal studies were designed and initiated. Understanding the basis and progression of radiation damage should also permit rational approaches to prevention and mitigation of those damages. Therefore, as stated earlier, these tissues and their related documentation, represent a significant resource for future studies. For this project, we propose to accomplish the following objectives: (1) inventory and organize the tissues, blood smears, wet-tissues and paper-¬based information that is available in the tissue bank at Argonne National Laboratory; (2) convert the existing Oracle database of the mouse studies to MS Access( the dog data is already in this format which is far more user friendly and widely used in business and research) , (3) move the remaining samples and documentation from dogs that had been transferred from ANL to New Mexico (in Dr. F. Hahn's care) to Northwestern University and add these to the inventory; (4) move the tissues and Access database at Argonne National Laboratory to Northwestern University.

Gayle Woloschak

2007-04-01

355

Microarrays (DNA Chips) for the Classroom Laboratory  

ERIC Educational Resources Information Center

|We have developed and optimized the necessary laboratory materials to make DNA microarray technology accessible to all high school students at a fraction of both cost and data size. The primary component is a DNA chip/array that students "print" by hand and then analyze using research tools that have been adapted for classroom use. The primary…

Barnard, Betsy; Sussman, Michael; BonDurant, Sandra Splinter; Nienhuis, James; Krysan, Patrick

2006-01-01

356

Making sense of microarray data distributions  

Microsoft Academic Search

Motivation: Typical analysis of microarray data has focused on spot by spot comparisons within a single organism. Less analysis has been done on the compar- ison of the entire distribution of spot intensities between experiments and between organisms. Results: Here we show that mRNA transcription data from a wide range of organisms and measured with a range of experimental platforms

David C. Hoyle; Magnus Rattray; Ray Jupp; Andy Brass

2002-01-01

357

A new method for gridding DNA microarrays.  

PubMed

In this paper, a new methodological scheme for the gridding of DNA microarrays is proposed. The scheme composes of a series of processes applied sequentially. Each DNA microarray image is pre-processed to remove any noise and the center of each spot is detected using a template matching algorithm. Then, an initial gridding is automatically placed on the DNA microarray image by 'building' rectangular pyramids around the detected spots' centers. The gridlines "move" between the pyramids, horizontally and vertically, forming this initial grid. Furthermore, a refinement process is applied composing of a five-step approach in order to correct gridding imperfections caused by its initial placement, both in non-spot cases and in more than one spot enclosure cases. The proposed gridding scheme is applied on DNA microarray images under known transformations and on real-world DNA data. Its performance is compared against the projection pursuit method, which is often used due to its speed and simplicity, as well as against a state-of-the-art method, the Optimal Multi-level Thresholding Gridding (OMTG). According to the obtained results, the proposed gridding scheme outperforms both methods, qualitatively and quantitatively. PMID:24034720

Charalambous, Christoforos C; Matsopoulos, George K

2013-07-02

358

Estimation of Transformation Parameters for Microarray Data  

Microsoft Academic Search

Motivation and Results: Durbin et al. (2002), Huber et al. (2002) and Munson (2001) independently introduced af amily of transformations (the generalized-log family) which stabilizes the variance of microarray data up to the first order. We introduce a method for estimating the transformation parameter in tandem with a linear model based on the procedure outlined in Box and Cox (1964).

Blythe Durbin; David M. Rocke

2003-01-01

359

Microarrays: how many do you need?  

Microsoft Academic Search

We estimate the number of microarrays that is required in order to gain reliable results from a common type of study: the pairwise comparison of different classes of samples. Current knowlegde seems to suffice for the construction of models that are realistic with respect to searches for individual differentially expressed genes. Such models allow to investigate the dependence of the

Alexander Zien; Juliane Fluck; Ralf Zimmert; Thomas Lengauer

2002-01-01

360

Shrinkage covariance matrix approach for microarray data  

NASA Astrophysics Data System (ADS)

Microarray technology was developed for the purpose of monitoring the expression levels of thousands of genes. A microarray data set typically consists of tens of thousands of genes (variables) from just dozens of samples due to various constraints including the high cost of producing microarray chips. As a result, the widely used standard covariance estimator is not appropriate for this purpose. One such technique is the Hotelling's T2 statistic which is a multivariate test statistic for comparing means between two groups. It requires that the number of observations (n) exceeds the number of genes (p) in the set but in microarray studies it is common that n < p. This leads to a biased estimate of the covariance matrix. In this study, the Hotelling's T2 statistic with the shrinkage approach is proposed to estimate the covariance matrix for testing differential gene expression. The performance of this approach is then compared with other commonly used multivariate tests using a widely analysed diabetes data set as illustrations. The results across the methods are consistent, implying that this approach provides an alternative to existing techniques.

Karjanto, Suryaefiza; Aripin, Rasimah

2013-04-01

361

Interpretation of microarray data in cancer  

PubMed Central

Microarray studies aim at identifying homogeneous subtypes of cancer patients, searching for differentially expressed genes in tumours with different characteristics, or predicting the prognosis of patients. Using breast cancer as an example, we discuss the hypotheses underlying these studies, their power, and the validity and the clinical usefulness of the findings.

Michiels, S; Koscielny, S; Hill, C

2007-01-01

362

Optimal gene expression analysis by microarrays  

Microsoft Academic Search

DNA microarrays make possible the rapid and comprehensive assessment of the transcriptional activity of a cell, and as such have proven valuable in assessing the molecular contributors to biological processes and in the classification of human cancers. The major challenge in using this technology is the analysis of its massive data output, which requires computational means for interpretation and a

Lance D. Miller; Philip M. Long; Limsoon Wong; Sayan Mukherjee; Lisa M. McShane; Edison T. Liu

2002-01-01

363

Microarray Analysis of Focal Segmental Glomerulosclerosis  

Microsoft Academic Search

Background: Focal segmental glomerulosclerosis (FSGS) is a leading cause of chronic renal failure in children. Recent studies have begun to define the molecular pathogenesis of this heterogeneous condition. Here we use oligonucleotide microarrays to obtain a global gene expression profile of kidney biopsy specimens from patients with FSGS in order to better understand the pathogenesis of this disease. Methods: We

Kristopher Schwab; David P. Witte; Bruce J. Aronow; Prasad Devarajan; S. Steven Potter; Larry T. Patterson

2004-01-01

364

Repeatability of published microarray gene expression analyses  

Microsoft Academic Search

Given the complexity of microarray-based gene expression studies, guidelines encourage transparent design and public data availability. Several journals require public data deposition and several public databases exist. However, not all data are publicly available, and even when available, it is unknown whether the published results are reproducible by independent scientists. Here we evaluated the replication of data analyses in 18

David B Allison; Catherine A Ball; Issa Coulibaly; Xiangqin Cui; Aedín C Culhane; Mario Falchi; Cesare Furlanello; Giuseppe Jurman; Jon Mangion; Tapan Mehta; Michael Nitzberg; Grier P Page; Enrico Petretto; Vera van Noort

2008-01-01

365

Comparing whole genomes using DNA microarrays  

Microsoft Academic Search

The rapid accumulation of complete genomic sequences offers the opportunity to carry out an analysis of inter- and intra-individual genome variation within a species on a routine basis. Sequencing whole genomes requires resources that are currently beyond those of a single laboratory and therefore it is not a practical approach for resequencing hundreds of individual genomes. DNA microarrays present an

David Gresham; Maitreya J. Dunham; David Botstein

2008-01-01

366

DNA Microarrays in Herbal Drug Research  

Microsoft Academic Search

Natural products are gaining increased applications in drug discovery and development. Being chemically diverse they are able to modulate several targets simultaneously in a complex system. Analysis of gene expression becomes necessary for better understanding of molecular mechanisms. Conventional strategies for expression profiling are optimized for single gene analysis. DNA microarrays serve as suitable high throughput tool for simultaneous analysis

Preeti Chavan; Kalpana Joshi; Bhushan Patwardhan

2006-01-01

367

High density peptide microarrays. In situ synthesis and applications  

Microsoft Academic Search

The technologies enabling the creation of large scale, miniaturized peptide or protein microarrays are emerging. The focuses of this review are the synthesis and applications of peptide and peptidomimetic microarrays, especially the light directed parallel synthesis of individually addressable high density peptide microarrays using a novel photogenerated reagent chemistry and digital photolithography (Gao et al., 1998, J. Am. Chem. Soc.

Xiaolian Gao; Jean Philippe Pellois; Younghwa Na; Younkee Kim; Erdogan Gulari; Xiaochuan Zhou

2004-01-01

368

Microarray-in-a-Tube for Detection of Multiple Viruses  

Microsoft Academic Search

Background: The detection of multiple viruses is im- portant for pathogenic diagnosis and disease control. Microarray detection is a good method, but requires complex procedures for multiple virus detection. Methods: We developed a novel PCR assay, the microar- ray-in-a-tube system, which integrates multiple PCR processes and DNA microarrays for multiple virus de- tection. A 5 5 oligonucleotide microarray for detecting

Quanjun Liu; Yunfei Bai; Qinyu Ge; Shixin Zhou; Tian Wen; Zuhong Lu

369

Application of Bioinformatics in the Design of Gene Expression Microarrays  

Microsoft Academic Search

The declaration that gene expression microarrays serve as invaluable tools for the global characterisation of entire genomes is widely accepted by the scientific community highly involved in microarray technology. Although microarrays have the power to distinguish between the expression levels of genes within cells that are representative of various conditions the immediate results require further mining to determine the genes,

Sabah Khalid; Mohsin Khan; Ping Wang; Xiaohui Liu; Su-Ling Li

2006-01-01

370

Clustering microarray gene expression data using type 2 fuzzy logic  

Microsoft Academic Search

Microarray technology helps biologists for monitoring expression of thousands of genes in a single experiment on a small chip. Microarray is also called as DNA chip, gene chip, or biochip is used to analyze gene expression. DNA microarrays are rapidly becoming a fundamental tool in genomic research. Bioinformatics and data mining provide exciting and challenging researches in several application areas

S. J. Brintha; V. Bhuvaneswari

2012-01-01

371

The EADGENE Microarray Data Analysis Workshop (open access publication)  

Microsoft Academic Search

Microarray analyses have become an important tool in animal genomics. While their use is becoming widespread, there is still a lot of ongoing research regarding the analysis of microarray data. In the context of a European Network of Excellence, 31 researchers representing 14 research groups from 10 countries performed and discussed the statistical analyses of real and simulated 2-colour microarray

Dirk-Jan de Koning; F. Jaffrezic; Mogens Sandø Lund; Michael Watson; Caroline Channing; Ina Hulsegge; Marco H. Pool; Bart Buitenhuis; Jakob Hedegaard; H. Hornshoj; Li Jiang; P. Sorensen; Guillemette Marot; Céline Delmas; Kim-Anh Lê Cao; Magali San Cristobal; Michael D. Baron; Roberto Malinverni; Alessandra Stella; Ronald M. Brunner; Hans-Martin Seyfert; Kirsty Jensen; Daphne Mouzaki; David Waddington; A. Jimenez-Marin; M. Perez-Alegre; E. Perez-Reinado; Rodrigue Closset; Johanne C. Detilleux; P. Dovc; M. Lavric; Haisheng Nie; Luc Janss

2007-01-01

372

The EADGENE Microarray Data Analysis Workshop (Open Access publication)  

Microsoft Academic Search

Microarray analyses have become an important tool in animal genomics. While their use is becoming widespread, there is still a lot of ongoing research regarding the analysis of microarray data. In the context of a European Network of Excellence, 31 researchers representing 14 research groups from 10 countries performed and discussed the statistical analyses of real and simulated 2-colour microarray

Dirk-Jan de Koning; Florence Jaffrézic; Mogens Sandø Lund; Michael Watson; Caroline Channing; Ina Hulsegge; Marco H Pool; Bart Buitenhuis; Jakob Hedegaard; Henrik Hornshøj; Li Jiang; Peter Sørensen; Guillemette Marot; Céline Delmas; Kim-Anh Lê Cao; Magali San Cristobal; Michael D Baron; Roberto Malinverni; Alessandra Stella; Ronald M Brunner; Hans-Martin Seyfert; Kirsty Jensen; Daphne Mouzaki; David Waddington; Ángeles Jiménez-Marín; Mónica Pérez-Alegre; Eva Pérez-Reinado; Rodrigue Closset; Johanne C Detilleux; Peter Dov?; Miha Lavri?; Haisheng Nie; Luc Janss

2007-01-01

373

Defining best practice for microarray analyses in nutrigenomic studies  

Microsoft Academic Search

Microarrays represent a powerful tool for studies of diet-gene interactions. Their use is, however, associated with a number of technical challenges and potential pitfalls. The cost of microarrays continues to drop but is still comparatively high. This, coupled with the complex logistical issues associated with performing nutritional microarray studies, often means that compromises have to be made in the number

Paola Garosi; Carlotta De Filippo; Marjan van Erk; Philippe Rocca-Serra; Susanna-Assunta Sansone; Ruan Elliott

2005-01-01

374

Monitoring gene expression profile changes in bladder transitional cell carcinoma using cDNA microarray  

Microsoft Academic Search

Purpose: Differential gene expression profiles between normal bladder mucosas and bladder transitional cell carcinomas TCC were detected. Materials and methods: cDNA microarrays were prepared by spotting PCR products of 12,800 human genes onto specially treated glass slides. The cDNA probes were prepared by labeling normal bladder mucosa mRNA and TCC tissue mRNA with Cy3-dUTP and Cy5-dUTP respectively through reverse transcription.

Sun Ying-Hao; Yang Qing; Wang Lin-Hui; Gao Li; Tang Rong; Ying Kang; Xu Chuan-Liang; Qian Song-Xi; Li Yao; Xie Yi; Mao Yu-Ming

2002-01-01

375

Identification of Differentially Expressed Genes in Pancreatic Cancer Cells Using cDNA Microarray1  

Microsoft Academic Search

To identify new diagnostic markers and drug targets for pancreatic cancer, we compared the gene expression patterns of pancreatic cancer cell lines growing in tissue culture with those of normal pancreas using cDNA microarray analysis. Fluorescently (cyanine 5) labeled cDNA probes, made individually from mRNA samples of nine pancreatic cell lines, were each combined with fluorescently (cyanine 3) labeled universal

Haiyong Han; David J. Bearss; L. Walden Browne; Robert Calaluce; Raymond B. Nagle; Hoff Dd Von

2002-01-01

376

Comparative Analysis of Human Conjunctival and Corneal Epithelial Gene Expression with Oligonucleotide Microarrays  

Microsoft Academic Search

PURPOSE. To determine global mRNA expression levels in cor- neal and conjunctival epithelia and identify transcripts that exhibit preferential tissue expression. METHODS. cDNA samples derived from human conjunctival and corneal epithelia were hybridized in three independent exper- iments to a commercial oligonucleotide array representing more than 22,000 transcripts. The resultant signal intensities and microarray software transcript present\\/absent calls were used

Helen C. Turner; Murat T. Budak; M. A. Murat Akinci; J. Mario Wolosin

2007-01-01

377

Microarray-based Gene Expression Analysis of Endocrine Systems: Principles of Experimental Design and Interpretation  

Microsoft Academic Search

The fundamental rationale for the use of microarray-based gene expression profiling to characterize biological samples is\\u000a based in part on the principle that cells, tissues, and perturbations applied to them can be characterized on the basis of\\u000a their relative expression of genes and transcripts. Different biological states, cell types, and influences can be distinguished\\u000a based on transcriptional profiles and the

Anil G. Jegga; Bruce J. Aronow; Stuart Handwerger

378

Transcript copy number estimation using a mouse whole-genome oligonucleotide microarray  

Microsoft Academic Search

The ability to quantitatively measure the expression of all genes in a given tissue or cell with a single assay is an exciting promise of gene-expression profiling technology. An in situ-synthesized 60-mer oligonucleotide microarray designed to detect transcripts from all mouse genes was validated, as well as a set of exogenous RNA controls derived from the yeast genome (made freely

Mark G Carter; Alexei A Sharov; Vincent VanBuren; Dawood B Dudekula; Condie E Carmack; Charlie Nelson; Minoru SH Ko

2005-01-01

379

Microarray analysis at single molecule resolution  

PubMed Central

Bioanalytical chip-based assays have been enormously improved in sensitivity in the recent years; detection of trace amounts of substances down to the level of individual fluorescent molecules has become state of the art technology. The impact of such detection methods, however, has yet not fully been exploited, mainly due to a lack in appropriate mathematical tools for robust data analysis. One particular example relates to the analysis of microarray data. While classical microarray analysis works at resolutions of two to 20 micrometers and quantifies the abundance of target molecules by determining average pixel intensities, a novel high resolution approach [1] directly visualizes individual bound molecules as diffraction limited peaks. The now possible quantification via counting is less susceptible to labeling artifacts and background noise. We have developed an approach for the analysis of high-resolution microarray images. It consists first of a single molecule detection step, based on undecimated wavelet transforms, and second, of a spot identification step via spatial statistics approach (corresponding to the segmentation step in the classical microarray analysis). The detection method was tested on simulated images with a concentration range of 0.001 to 0.5 molecules per square micron and signal-to-noise ratio (SNR) between 0.9 and 31.6. For SNR above 15 the false negatives relative error was below 15%. Separation of foreground/background proved reliable, in case foreground density exceeds background by a factor of 2. The method has also been applied to real data from high-resolution microarray measurements.

Muresan, Leila; Jacak, Jaroslaw; Klement, Erich Peter; Hesse, Jan; Schutz, Gerhard J.

2010-01-01

380

Facilitating functional annotation of chicken microarray data  

PubMed Central

Background Modeling results from chicken microarray studies is challenging for researchers due to little functional annotation associated with these arrays. The Affymetrix GenChip chicken genome array, one of the biggest arrays that serve as a key research tool for the study of chicken functional genomics, is among the few arrays that link gene products to Gene Ontology (GO). However the GO annotation data presented by Affymetrix is incomplete, for example, they do not show references linked to manually annotated functions. In addition, there is no tool that facilitates microarray researchers to directly retrieve functional annotations for their datasets from the annotated arrays. This costs researchers amount of time in searching multiple GO databases for functional information. Results We have improved the breadth of functional annotations of the gene products associated with probesets on the Affymetrix chicken genome array by 45% and the quality of annotation by 14%. We have also identified the most significant diseases and disorders, different types of genes, and known drug targets represented on Affymetrix chicken genome array. To facilitate functional annotation of other arrays and microarray experimental datasets we developed an Array GO Mapper (AGOM) tool to help researchers to quickly retrieve corresponding functional information for their dataset. Conclusion Results from this study will directly facilitate annotation of other chicken arrays and microarray experimental datasets. Researchers will be able to quickly model their microarray dataset into more reliable biological functional information by using AGOM tool. The disease, disorders, gene types and drug targets revealed in the study will allow researchers to learn more about how genes function in complex biological systems and may lead to new drug discovery and development of therapies. The GO annotation data generated will be available for public use via AgBase website and will be updated on regular basis.

2009-01-01

381

Raman Microprobe Investigation of Molecular Structure and Organization in the Native State of Woody Tissue: Progress Report, July 1, 1985-June 30, 1986.  

National Technical Information Service (NTIS)

Raman microprobe spectroscopy has been used to investigate molecular architecture in the cell walls of native woody tissue. At the outset it was demonstrated that spectra can be acquired from cell wall domains as small as 1 to 3 micrometers in diameter, a...

R. H. Atalla

1986-01-01

382

Decreased nuclear expression and increased cytoplasmic expression of ING5 may be linked to tumorigenesis and progression in human head and neck squamous cell carcinoma  

Microsoft Academic Search

Purpose  This study aimed to assess the protein level of inhibitor of growth gene 5 (ING5) in head and neck squamous cell carcinoma (HNSCC) and to explore its roles in tumorigenesis and cancer progression.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  ING5 expression was assessed in 172 cases of HNSCC by immunohistochemistry using tissue microarray, and in 3 oral SCC cell\\u000a lines by immunohistochemistry and Western blot. Expression

Xiaohan Li; Takeshi Nishida; Akira Noguchi; Yang Zheng; Hiroyuki Takahashi; Xianghong Yang; Shinji Masuda; Yasuo Takano

2010-01-01

383

Home-built integrated microarray system (IMAS). A three-laser confocal fluorescence scanner coupled with a microarray printer  

Microsoft Academic Search

Microarray technology covers the urgent need to exploit the accumulated genetic information from large-scale sequencing projects\\u000a and facilitate investigations on a genome-wide scale. Although most applications focus on DNA microarrays, the technology\\u000a has expanded to microarrays of proteins, peptides, carbohydrates, and small molecules aiming either at detection\\/quantification\\u000a of biomolecules or investigation of biomolecular interactions in a massively parallel manner. Microarray

Sotirios S. Tragoulias; Pierre J. Obeid; Ioannis E. Tataridis; Theodore K. Christopoulos

2008-01-01

384

Pattern Formation in the Absence of Cell Proliferation: Tissue-Specific Regulation of Cell Cycle Progression by string ( stg) during Drosophila Eye Development  

Microsoft Academic Search

During Drosophila eye development, the posterior-to-anterior movement of the morphogenetic furrow coordinates cell cycle progression with the early events of pattern formation. The cdc25 phosphatase string (stg) has been proposed to contribute to the synchronization of retinal precursors anterior to the furrow by driving cells in G2 through mitosis and into a subsequent G1. Genetic and molecular analysis of Drop

Brian A. Mozer; Kumanan Easwarachandran

1999-01-01

385

Evaluation of microarray surfaces and arraying parameters for autoantibody profiling  

PubMed Central

Autoantigen microarrays are being used increasingly to study autoimmunity. Significant variation has been observed when comparing microarray surfaces, printing methods, and probing conditions. In the present study, 24 surfaces and several arraying parameters were analyzed using >500 feature autoantigen microarrays printed with quill pins. A small subset of slides, including FAST®, PATH®, and SuperEpoxy2, performed well while maintaining the sensitivity and specificity of autoantigen microarrays previously demonstrated by our laboratory. By optimizing the major variables in our autoantigen microarray platform, subtle differences in serum samples can be identified that will shed light on disease pathogenesis.

Balboni, Imelda; Limb, Cindy; Tenenbaum, Jessica D.; Utz, Paul J.

2012-01-01

386

High-Throughput Nano-Biofilm Microarray for Antifungal Drug Discovery  

PubMed Central

ABSTRACT Micro- and nanoscale technologies have radically transformed biological research from genomics to tissue engineering, with the relative exception of microbial cell culture, which is still largely performed in microtiter plates and petri dishes. Here, we present nanoscale culture of the opportunistic fungal pathogen Candida albicans on a microarray platform. The microarray consists of 1,200 individual cultures of 30 nl of C. albicans biofilms (“nano-biofilms”) encapsulated in an inert alginate matrix. We demonstrate that these nano-biofilms are similar to conventional macroscopic biofilms in their morphological, architectural, growth, and phenotypic characteristics. We also demonstrate that the nano-biofilm microarray is a robust and efficient tool for accelerating the drug discovery process: (i) combinatorial screening against a collection of 28 antifungal compounds in the presence of immunosuppressant FK506 (tacrolimus) identified six drugs that showed synergistic antifungal activity, and (ii) screening against the NCI challenge set small-molecule library identified three heretofore-unknown hits. This cell-based microarray platform allows for miniaturization of microbial cell culture and is fully compatible with other high-throughput screening technologies.

Srinivasan, Anand; Leung, Kai P.; Lopez-Ribot, Jose L.; Ramasubramanian, Anand K.

2013-01-01

387

Quantitative expression profiling of highly degraded RNA from formalin-fixed, paraffin-embedded breast tumor biopsies by oligonucleotide microarrays  

Microsoft Academic Search

Microarray-based gene expression profiling is well suited for parallel quantitative analysis of large numbers of RNAs, but its application to cancer biopsies, particularly formalin-fixed, paraffin-embedded (FFPE) archived tissues, is limited by the poor quality of the RNA recovered. This represents a serious drawback, as FFPE tumor tissue banks are available with clinical and prognostic annotations, which could be exploited for

Maria Ravo; Margherita Mutarelli; Lorenzo Ferraro; Olì Maria Victoria Grober; Ornella Paris; Roberta Tarallo; Alessandra Vigilante; Daniela Cimino; Michele De Bortoli; Ernesto Nola; Luigi Cicatiello; Alessandro Weisz

2008-01-01

388

Dysregulation of the Annexin Family Protein Family Is Associated with Prostate Cancer Progression  

PubMed Central

Hormone refractory prostate cancer (PCa) is invariably lethal despite aggressive clinical treatment strategies. Detection strategies are needed to identify aggressive PCa before it becomes widely disseminated. Recently, two studies identified annexin 1 and 7 as potential biomarkers in the development of PCa progression. The annexins are a group of calcium-binding structural proteins that may play a role in the regulation of membrane trafficking, cellular adhesion, and cell signaling. Therefore the goal of this study is to simultaneously characterize the multiple members of the annexin family of genes in advanced PCa. Prostate samples from men with advanced hormone refractory PCa were compared to samples of hormone-naïve PCa and noncancerous prostate tissue. Samples from 15 patients with advanced hormone refractory PCa were used. To examine the annexin family, gene expression profiles from 21 noncancerous prostate tissues, 16 clinically localized PCas, and 20 hormone refractory PCa samples were used. By cDNA microarray analysis, annexins 1, 2, 4, 7, and 11 were significantly decreased in hormone refractory PCa when compared to localized hormone-naïve PCa with 2.2-, 1.5-, 1.3-, 1.4-, and 1.8-fold decreases, respectively (all P values <0.05). Interstudy validation of annexin family transcript expression was performed by meta-analysis of three other published prostate profiling studies. High-density tissue microarrays were used to validate a subset of annexins at the protein level by immunohistochemistry. Tissue microarray analysis revealed a significant decrease in protein expression for annexins 1, 2, 4, 7, and 11 in hormone refractory PCa as compared to localized PCa with 1.68-, 2.46-, 2.52-, and 3.01-fold decreases, respectively (Kruskal Wallis test, all P values P < 0.05). However, no significant differences were detected between the clinically localized PCa and noncancerous prostate tissues. These findings suggest that down-regulation of several members of the annexin family may contribute to PCa tumorigenesis. Annexins 1, 2, 4, 7, and 11 may play a role in tumor progression through distinct mechanisms or, alternatively, they may have redundant tumor suppressor activities. This study also suggests that a meta-analysis of existing gene expression data is useful in confirming findings from individual studies. Finally, down-regulation of several annexin family members may play a role in the development of the lethal PCa phenotype.

Xin, Wei; Rhodes, Daniel R.; Ingold, Collette; Chinnaiyan, Arul M.; Rubin, Mark A.

2003-01-01

389

Testing an Aflatoxin B1 Gene Signature in Rat Archival Tissues  

PubMed Central

Archival tissues from laboratory studies represent a unique opportunity to explore the relationship between genomic changes and agent-induced disease. In this study, we evaluated the applicability of qPCR for detecting genomic changes in formalin-fixed, paraffin-embedded (FFPE) tissues by determining if a subset of 14 genes from a 90-gene signature derived from microarray data and associated with eventual tumor development could be detected in archival liver, kidney, and lung of rats exposed to aflatoxin B1 (AFB1) for 90 days in feed at 1 ppm. These tissues originated from the same rats used in the microarray study. The 14 genes evaluated were Adam8, Cdh13, Ddit4l, Mybl2, Akr7a3, Akr7a2, Fhit, Wwox, Abcb1b, Abcc3, Cxcl1, Gsta5, Grin2c and C8orf46 homolog. The qPCR FFPE liver results were compared to the original liver microarray data and to qPCR results using RNA from fresh frozen liver. Archival liver paraffin blocks yielded 30 to 50 ?g of degraded RNA that ranged in size from 0.1 to 4 kB. qPCR results from FFPE and fresh frozen liver samples were positively correlated (p?0.05) by regression analysis and showed good agreement in direction and proportion of change with microarray data for 11 of 14 genes. All 14 transcripts could be amplified from FFPE kidney RNA except the glutamate receptor gene Grin2c; however, only Abcb1b was significantly upregulated from control. Abundant constitutive transcripts, S18 and ?-actin, could be amplified from lung FFPE samples, but the narrow RNA size range (25–500 bp length) prevented consistent detection of target transcripts. Overall, a discrete gene signature derived from prior transcript profiling and representing cell cycle progression, DNA damage response, and xenosensor and detoxication pathways was successfully applied to archival liver and kidney by qPCR and indicated that gene expression changes in response to subchronic AFB1 exposure occurred predominantly in liver, the primary target for AFB1-induced tumors. We conclude that an evaluation of gene signatures in archival tissues can be an important toxicological tool for evaluating critical molecular events associated with chemical exposures.

Merrick, B. Alex; Auerbach, Scott S.; Stockton, Patricia S.; Foley, Julie F.; Malarkey, David E.; Sills, Robert C.; Irwin, Richard D.; Tice, Raymond R.

2012-01-01

390

Glycan microarrays for decoding the glycome  

PubMed Central

In the last decade glycan microarrays have revolutionized the analysis of the specificity of glycan binding proteins, providing information that simultaneously illuminates the biology mediated by them and decodes the information content of the glycome. Numerous methods have emerged for arraying glycans in a ‘chip’ format, and glycan libraries have been assembled that address the diversity of the human glycome. Such arrays have been successfully used for analysis of glycan binding proteins that mediate mammalian biology, host-pathogen interactions, immune recognition of glycans relevant to vaccine production and cancer antigens. This review covers the development of glycan microarrays and applications that have provided insights into the roles of mammalian and microbial glycan binding proteins.

Rillahan, Cory D.; Paulson, James C.

2011-01-01

391

Solution processed organic microarray with inverted structure  

NASA Astrophysics Data System (ADS)

We have fabricated inverted organic microarray using a novel solution-based technique. The array consists of 60 small (1 square mm) solar cells on a one inch by one inch glass substrate. The device utilizes photoactive materials such as a blend of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM). Manipulation of active layer nanomorphology has been done by choice of solvents and annealing conditions. Detailed analysis of device physics including current voltage characteristics, external quantum efficiency and carrier recombinations will be presented and complimented by AFM images and glazing angle XRD of the active layer under different processing conditions. The procedure described here has the full potential for use in future fabrication of microarrays with single cell as small as 0.01 square mm for application in DC power supplies for electrostatic Microelectromechanical systems (MEMS) devices.

Toglia, Patrick; Lewis, Jason; Lafalce, Evan; Jiang, Xiaomei

2011-03-01

392

Biclustering models for structured microarray data.  

PubMed

Microarrays have become a standard tool for investigating gene function and more complex microarray experiments are increasingly being conducted. For example, an experiment may involve samples from several groups or may investigate changes in gene expression over time for several subjects, leading to large three-way data sets. In response to this increase in data complexity, we propose some extensions to the plaid model, a biclustering method developed for the analysis of gene expression data. This model-based method lends itself to the incorporation of any additional structure such as external grouping or repeated measures. We describe how the extended models may be fitted and illustrate their use on real data. PMID:17044169

Turner, Heather L; Bailey, Trevor C; Krzanowski, Wojtek J; Hemingway, Cheryl A

393

Combined treatment with recombinant tissue plasminogen activator and dexamethasone phosphate-containing liposomes improves neurological outcome and restricts lesion progression after embolic stroke in rats.  

PubMed

Variable efficacies have been reported for glucocorticoid drugs as anti-inflammatory treatment after stroke. We applied an alternative drug delivery strategy, by injection of dexamethasone phosphate-containing liposomes in combination with recombinant tissue plasminogen activator (rtPA), in an experimental stroke model, and tested the hypothesis that this approach improves behavioral recovery and reduces lesion growth. Rats were subjected to right middle cerebral artery occlusion with a blood clot. After 2 h, animals were intravenously injected with rtPA plus empty long-circulating liposomes (LCL), free dexamethasone phosphate (DXP), or DXP-containing LCL (LCL-DXP). Neurological status was evaluated with different behavioral tests up to 7 days after stroke. Lesion development was assessed by magnetic resonance imaging of tissue and perfusion parameters from 0-2 h until 7 days after stroke. Expression of brain inflammatory markers was measured with RT-PCR at post-stroke day 7. Treatment with rtPA plus LCL-DXP resulted in significantly improved behavioral outcome as compared to treatment with rtPA plus empty LCL or free DXP. Acute and final brain lesion sizes were comparable between treatment groups; however a predictive algorithm revealed a significantly larger salvaged tissue area after treatment with LCL-DXP. We conclude that delivery of dexamethasone phosphate via LCL in combination with rtPA-induced thrombolysis can significantly improve outcome after stroke. Furthermore, magnetic resonance imaging-based predictive algorithms provide a sensitive means to measure treatment effects on lesion development. PMID:23050644

Tiebosch, Ivo A C W; Crielaard, Bart J; Bouts, Mark J R J; Zwartbol, René; Salas-Perdomo, Angelica; Lammers, Twan; Planas, Anna M; Storm, Gert; Dijkhuizen, Rick M

2012-11-01

394

The evolution of microarrayed compound screening  

Microsoft Academic Search

This review describes recent developments in the evolutionary process of microarrayed compound screening (?ARCS™) to become a robust and efficient ultra-high-throughput screening technology. Improvements in compound spotting (including new quality-control methods), gel casting and imaging, together with software capable of automatic analysis and deconvolution of images, have helped to streamline the screening process. A variety of screening projects using cell-based

Michael Hoever; Peter Zbinden

2004-01-01

395

Human brain evolution: insights from microarrays  

Microsoft Academic Search

Several recent microarray studies have compared gene-expression patterns n humans, chimpanzees and other non-human primates to identify evolutionary changes that contribute to the distinctive cognitive and behavioural characteristics of humans. These studies support the surprising conclusion that the evolution of the human brain involved an upregulation of gene expression relative to non-human primates, a finding that could be relevant to

Mario Cáceres; Michael C. Oldham; Todd M. Preuss; Daniel H. Geschwind

2004-01-01

396

Evaluating Microarray-based Classifiers: An Overview  

PubMed Central

For the last eight years, microarray-based class prediction has been the subject of numerous publications in medicine, bioinformatics and statistics journals. However, in many articles, the assessment of classification accuracy is carried out using suboptimal procedures and is not paid much attention. In this paper, we carefully review various statistical aspects of classifier evaluation and validation from a practical point of view. The main topics addressed are accuracy measures, error rate estimation procedures, variable selection, choice of classifiers and validation strategy.

Boulesteix, A.-L.; Strobl, C.; Augustin, T.; Daumer, M.

2008-01-01

397

Diagnostic Oligonucleotide Microarray Fingerprinting of Bacillus Isolates  

Microsoft Academic Search

A diagnostic, genome-independent microbial fingerprinting method using DNA oligonucleotide microarrays was used for high-resolution differentiation between closely related Bacillus strains, including two strains of Bacillus anthracis that are monomorphic (indistinguishable) via amplified fragment length polymorphism fingerprinting techniques. Replicated hybridizations on 391-probe nonamer arrays were used to construct a prototype fingerprint library for quantitative comparisons. Descriptive analysis of the fingerprints, including