Background. Most colorectal cancers (CRC) arise in a progression through adenoma to carcinoma phenotypes as a consequence of altered genetic information. Clinical progression of CRC may occur in parallel with distinctive signaling alterations. We designed multidirectional analyses integrating microarray-based data with biostatistics and bioinformatics to elucidate the signaling and metabolic alterations underlying CRC development in the adenoma-carcinoma sequence. Methodology/Principal Findings. Studies were performed on normal mucosa, adenoma, and CRC samples obtained during surgery or colonoscopy. Collections of cryostat sections prepared from the tissue samples were evaluated by a pathologist to control the relative cell type content. RNA was isolated from 105 macro- and 40 microdissected specimens. The measurements were done using Affymetrix GeneChip HG-U133plus2, and probe set data were generated using two normalization algorithms: MAS5 and GCRMA with LVS. The data were evaluated using pair-wise comparisons and data decomposition into SVD modes. The method selected for the functional analysis used the Kolmogorov-Smirnov test. Based on a consensus of the results obtained by two tissue handling procedures, two normalization algorithms, and two probe set sorting criteria, we identified six KEGG signaling and metabolic pathways (cell cycle, DNA replication, p53 signaling pathway, purine metabolism, pyrimidine metabolism, and RNA polymerase) that are significantly altered in both macro- and microdissected tumor samples compared to normal colon. On the other hand, pathways altered between benign and malignant tumors were identified only in the macrodissected tissues. Conclusion/Significance. Multidirectional analyses of microarray data allow the identification of essential signaling alterations underlying CRC development. Although the proposed strategy is computationally complex and laborintensive, it may reduce the number of false results.
Modeling oncogenic signaling in colon tumors by multidirectional analyses of microarray data directed for maximization of analytical reliability.
Sex, Age, Specimen part
View SamplesAlthough mitochondrial dysfunctions are implicated in the pathogenesis of obesity, the molecular mechanisms underlying obesity-related metabolic abnormalities are still not well established. To acquire a comprehensive picture of mitochondrial molecular changes within metabolically active tissues, we focused on hepatic and muscle whole cellular transcriptome and mitochondrial proteome alterations in 16 and 48 weeks old high fat diet (HFD)-feed wild type C57BL/6J and hyperphagic, genetically modified mice with leptin dysfunction (ob/ob and db/db).
No associated publication
Age, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
DNA methylation status is more reliable than gene expression at detecting cancer in prostate biopsy.
No sample metadata fields
View SamplesThe aim of this study was to analyze critically the potential usefulness of selected RNA biomarkers in supporting conventional histological diagnostic tests for PCa. The selection of potential biomarkers was conducted by microarray profiling of gene expression on prostate tissues extracted from the gland after total radical prostatectomy.
No associated publication
No sample metadata fields
View SamplesBarrett's esophagus is characterized by the replacement of squamous epithelium with specialized intestinal metaplastic mucosa. The exact mechanisms of initiation and development of Barrett's metaplasia remain unknown, but a hypothesis of successful adaptation against noxious reflux components has been proposed. To search for the repertoire of adaptation mechanisms of Barrett's metaplasia, we employed high-throughput functional genomic and proteomic methods that defined the molecular background of metaplastic mucosa resistance to reflux. Transcriptional profiling was established for 23 pairs of esophageal squamous epithelium and Barrett's metaplasia tissue samples using Affymetrix U133A 2.0 GeneChips and validated by quantitative real-time polymerase chain reaction. Differences in protein composition were assessed by electrophoretic and mass-spectrometry-based methods. Among 2,822 genes differentially expressed between Barrett's metaplasia and squamous epithelium, we observed significantly overexpressed metaplastic mucosa genes that encode cytokines and growth factors, constituents of extracellular matrix, basement membrane and tight junctions, and proteins involved in prostaglandin and phosphoinositol metabolism, nitric oxide production, and bioenergetics. Their expression likely reflects defense and repair responses of metaplastic mucosa, whereas overexpression of genes encoding heat shock proteins and several protein kinases in squamous epithelium may reflect lower resistance of normal esophageal epithelium than Barrett's metaplasia to reflux components. Despite the methodological and interpretative difficulties in data analyses discussed in this paper, our studies confirm that Barrett's metaplasia may be regarded as a specific microevolution allowing for accumulation of mucosal morphological and physiological changes that better protect against reflux injury.
Molecular defense mechanisms of Barrett's metaplasia estimated by an integrative genomics.
Sex, Age
View SamplesGastrointestinal stromal tumours (GISTs) represent a heterogeneous group of tumours of mesenchymal origin characterized by gain-of-function mutations in KIT or PDGFRA of the type III receptor tyrosine kinase family. Although mutations in either receptor are thought to drive an early oncogenic event through similar pathways, two previous studies reported the mutation-specific gene expression profiles. However, their further conclusions were rather discordant. To clarify the molecular characteristics of differentially expressed genes according to GIST receptor mutations, we combined microarray-based analysis with detailed functional annotations.
Functional features of gene expression profiles differentiating gastrointestinal stromal tumours according to KIT mutations and expression.
Sex, Specimen part, Disease stage
View SamplesBackground: Macrophages are important cells in pathogenesis of obstructive lung diseases including asthma and chronic obstructive pulmonary disease (COPD). The aim of the study was a multivariate, genetic, comparative analysis of macrophages from patients with asthma and COPD.
Genetic characterization of macrophages from induced sputum of patients with asthma and chronic obstructive pulmonary disease.
Specimen part, Disease
View SamplesBACKGROUND: Regional lymph node (LN) status is a well-known prognostic factor for vulvar carcinoma (VC) patients. Although the reliable LN assessment in VC is crucial, it presents significant diagnostic problems. PURPOSE: We aimed to identify specific mRNA markers of VC dissemination in the LN and to address the feasibility of predicting the risk of nodal recurrence by the patterns of gene expression. EXPERIMENTAL DESIGN: Sentinel and inguinal LN samples from 20 patients who had undergone surgery for stage T1-3, N0-2, M0 primary vulvar squamous cell carcinoma were analyzed. Gene expression profiles were assessed in four metastatic [LN(+)] and four histologically negative [LN(-)] lymph node samples obtained from four VC patients, by the Affymetrix U133 Plus 2.0 gene expression microarrays. Of the set of genes of the highest expression in the metastatic LNs compared to LN(-), seven candidate marker genes were selected PERP, S100A8, FABP5, SFN, CA12, JUP and CSTA, and the expression levels of these genes were further analyzed by the real-time reverse transcription polymerase chain reaction (qRT-PCR) in 71 LN samples. RESULTS: Five of the genes, PERP, S100A8, FABP5, SFN and CA12, were significantly increased in LN(+) compared to LN(-) samples. In the initial validation of the seven putative markers of metastatic LN, the Cox proportional hazard model pointed to SFN and CA12 expression to significantly relate to the time to groin recurrence in VC patients. CONCLUSIONS: PERP, S100A8, FABP5, SFN and CA12 have a potential of marker genes for the molecular testing of LN involvement in VC patients.
No associated publication
Sex
View SamplesThis file contains the expression data for pediatric medulloblastomas and ependymomas
Differential expression and prognostic significance of SOX genes in pediatric medulloblastoma and ependymoma identified by microarray analysis.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Transcriptome analysis of Wnt3a-treated triple-negative breast cancer cells.
Cell line
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