Project description:Whole genomic microarray analysis was performed in order to identify gene expression profile alterations focusing on the dysplastic adenoma-carcinoma transition. Our aims were to determinate characteristic transcript sets for developing diagnostic mRNA expression patterns for objective classification of benign and malignant colorectal diseases and to test the classificatory power of these markers on an independent sample set. Total RNA was extracted from colonic biopsy samples of histologically negative patients and of patients with adenoma or colorectal cancer and were hybridized on Affymetrix HGU133 Plus 2.0 microarrays
Project description:Background and Aims: Gene expression analysis of colon biopsies using high-density oligonucleotide microarray can contribute to the understanding of local pathophysiological alterations and to functional classification of precancerous adenoma, different stage colorectal carcinomas (CRC) and inflammatory bowel diseases (IBD). Results: Significant overexpression of collagen IV, lipocalin-2, caveolin-1, calumenin genes, and significant dowregulation of aquaporin-8, amnionless homolog, prostaglandin D2 receptor genes were detected in CRC patients compared to normal. Adenoma samples were characterized by upregulated CD44 antigen, met proto-oncogene and downregulated chemokine ligand-12, ADAM-like decysin-1 and ATP-binding casette A8 discriminatory genes. In IBD samples significantly increased lipocalin-2, interferon induced transmembrane protein 1 and 3 mRNA levels, decreased zinc finger protein 91 and transient receptor potential cation channel M6 mRNA levels were found. Ulcerative colitis and Crohn’s disease can be distinguished according to the top five genes: cyclin-G2; tripartite motif-containing-31; TNFR shedding aminopeptidase regulator-1; C-type lectin superfamily member-14 and AMICA. 88.3-97.8% of the cases was correctly classified according to discriminatory genes. Conclusions: Our whole genomic microarray analysis of biopsy samples provides discriminative signatures, and an insight into pathophysiological background of colonic diseases. The results afford a data warehouse which can be further mined for in-depth pathway analyses. Keywords: Colon biopsy specimens in diseased and normal state
Project description:The entire small intestine was obseved by balloon endoscopy. Biopsy specimens were taken from jejunum, ileum and colon, respectively.
Project description:Genetic and epigenetic alterations are a fundamental aspect of colorectal cancer formation. There is considerable heterogeneity between colorectal cancers regarding the mutations and methylated genes they carry, and this heterogeneity may arise early in the polyp-cancer sequence. However, our understanding of the epigenetic alterations and gene mutations in colon adenomas and their relation to colorectal cancer is incomplete. Thus, we have assessed the methylome in normal colon mucosa, tubular adenomas, and colorectal adenocarcinomas and have determined the relationship of these findings between adenomas and cancer in the colon. Genome-wide alterations in DNA methylation were found in the normal colon mucosa adjacent to colorectal cancer, tubular adenomas, and colorectal cancer. Three subgroups of CRCs and two subgroups of adenomas were identified on the basis of their DNA methylation patterns. The adenomas separated into a high-frequency methylation class (Adenoma-H) and a low-frequency methylation class. The adenoma-H polyps have a methylated DNA signature similar to non-CIMP CRCs, whereas those of the Adenoma-L class have a similar methylation pattern to normal colon mucosa. The CpGs that account for these signatures are located in intragenic/intergenic regions, which suggests that these two groups of adenomas arise from different stem cell populations.
Project description:Genetic and epigenetic alterations are a fundamental aspect of colorectal cancer formation. There is considerable heterogeneity between colorectal cancers regarding the mutations and methylated genes they carry, and this heterogeneity may arise early in the polyp-cancer sequence. However, our understanding of the epigenetic alterations and gene mutations in colon adenomas and their relation to colorectal cancer is incomplete. Thus, we have assessed the methylome in normal colon mucosa, tubular adenomas, and colorectal adenocarcinomas and have determined the relationship of these findings between adenomas and cancer in the colon. Genome-wide alterations in DNA methylation were found in the normal colon mucosa adjacent to colorectal cancer, tubular adenomas, and colorectal cancer. Three subgroups of CRCs and two subgroups of adenomas were identified on the basis of their DNA methylation patterns. The adenomas separated into a high-frequency methylation class (Adenoma-H) and a low-frequency methylation class. The adenoma-H polyps have a methylated DNA signature similar to non-CIMP CRCs, whereas those of the Adenoma-L class have a similar methylation pattern to normal colon mucosa. The CpGs that account for these signatures are located in intragenic/intergenic regions, which suggests that these two groups of adenomas arise from different stem cell populations. We conducted genome-wide array-based studies and comprehensive data analyses of aberrantly methylated loci in 41 normal colon samples, 42 colon adenomas, and 64 colorectal cancers. Supplementary file 'GSE48684_Matrix_signal_intensities_1.txt.gz': includes the unmethylated and methylated signal intensities from Samples GSM1183439-GSM1183561. Supplementary file 'GSE48684_Matrix_signal_intensities_2.txt.gz': includes the unmethylated and methylated signal intensities from Samples GSM1235135-GSM1235158.
Project description:Inflammation has been identified as an important factor in cancer development and progression, including colorectal cancer [CRC]. To determine the role of inflammation and the specific contribution of activated fibroblasts in cancer development and progression we analyzed six human CRC tissue specimens and paired normal adjacent mucosa samples by LS/MS-MS. Amongst other, indeed several inflammation associated proteins were found differentially expressed compared to normal colonic mucosa. Two candidate molecules, SPARC and THBS2 were recently identified as proteins of a fibroblast inflammation signature. Analysis of public available RNA expression datasets revealed, that the mRNA of both SPARC and THBS2 are upregulated in CRC, typically in association with the CRC consensus molecular subtype 4 [CMS4]. Immunohistochemistry staining also demonstrated upregulation of SPARC and THBS2 in the tumor stroma compared to normal adjacent mucosa and indicated co-localization with the mesenchymal marker [alpha]SMA. In vitro 3D co-culture experiments with human colon derived fibroblasts and CRC cell lines resulted in enhanced SPARC and THBS2 protein levels when both cell types were cultivated in direct physical contact, compared to fibroblasts or cancer cells alone. This study demonstrates the feasibility of detecting tumor-specific signatures by LC-MS/MS and compatibility with RNA expression datasets. We identified an inflammation signature in CRC tissue and the data emphasized the contribution of activated fibroblasts in these events.
Project description:Whole transcriptome expression levels of healthy colonic, colorectal adenoma and colorectal cancer biopsy samples were analyzed by HTA 2.0 microarrays
Project description:Histological classification by routine pathology assessment with hematoxylin-eosin staining and immunostaining for poorly differentiated tumors, particularly those from small biopsies, is still challenging. In this study, using gene expression profiles of pathologically-determined lung squamous cell carcinomas and adenocarcinomas, denoted as pSCC and pADC respectively, we developed a qualitative transcriptional signature, based on the within-sample relative gene expression orderings (REOs) of gene pairs, to individually distinguish ADC from SCC. The signature was validated in the frozen tissues, FFPE materials, mixed tumors, small biopsy specimens and poorly differentiated samples.In summary, the qualitative signature, independent of the subjective diagnosis of pathologists, would be an effective auxiliary tool in distinguishing ADC from SCC.