Project description:Liver metastasis is one of the major causes of death in colorectal cancer (CRC) patients. To understand this process, we investigated whether the gene expression profiling of matched colorectal carcinomas and liver metastases could reveal key molecular events involved in tumor progression and metastasis. We performed experiments using a cDNA microarray containing 17,104 genes with the following tissue samples: paired tissues of 25 normal colorectal mucosa, 27 primary colorectal tumors, 13 normal liver and 27 liver metastasis, and 20 primary colorectal tumors without liver metastasis. To remove the effect of normal cell contamination, we selected 4,583 organ-specific genes with a false discovery rate (FDR) of 0.0067% by comparing normal colon and liver tissues using significant analysis of microarray, and these genes were excluded from further analysis. We then identified and validated 46 liver metastasis-specific genes with an accuracy of 83.3% by comparing the expression of paired primary colorectal tumors and liver metastases using prediction analysis of microarray. The 46 selected genes contained several known oncogenes and 2 ESTs. To confirm that the results correlated with the microarray expression patterns, we performed RT-PCR with WNT5A and carbonic anhydrase II. Additionally, we observed that 21 of the 46 genes were differentially expressed (FDR = 2.27%) in primary tumors with synchronous liver metastasis compared with primary tumors without liver metastasis. We scanned the human genome using a cDNA microarray and identified 46 genes that may play an important role in the progression of liver metastasis in CRC. Keywords: gene expression profiling using cDNA microarray We performed 17K cDNA microarray with the amplified RNAs from the following tissue samples: normal colorectal mucosa, primary colorectal tumors, normal liver and liver metastasis tumors, and primary colorectal tumors without liver metastasis. Organ-specific genes in normal colon and liver tissues were excluded from the pre-filtered genes, and then we discovered and validated liver metastasis-specific genes commonly up-regulated in the primary colorectal tumors and liver metastasis tumors. To confirm the microarray data, we performed a RT-PCR of two genes (WNT5A and carbonic anhydrase II) in the primary colorectal tumors with and without liver metastases.
Project description:Liver metastasis is one of the major causes of death in colorectal cancer (CRC) patients. To understand this process, we investigated whether the gene expression profiling of matched colorectal carcinomas and liver metastases could reveal key molecular events involved in tumor progression and metastasis. We performed experiments using a cDNA microarray containing 17,104 genes with the following tissue samples: paired tissues of 25 normal colorectal mucosa, 27 primary colorectal tumors, 13 normal liver and 27 liver metastasis, and 20 primary colorectal tumors without liver metastasis. To remove the effect of normal cell contamination, we selected 4,583 organ-specific genes with a false discovery rate (FDR) of 0.0067% by comparing normal colon and liver tissues using significant analysis of microarray, and these genes were excluded from further analysis. We then identified and validated 46 liver metastasis-specific genes with an accuracy of 83.3% by comparing the expression of paired primary colorectal tumors and liver metastases using prediction analysis of microarray. The 46 selected genes contained several known oncogenes and 2 ESTs. To confirm that the results correlated with the microarray expression patterns, we performed RT-PCR with WNT5A and carbonic anhydrase II. Additionally, we observed that 21 of the 46 genes were differentially expressed (FDR = 2.27%) in primary tumors with synchronous liver metastasis compared with primary tumors without liver metastasis. We scanned the human genome using a cDNA microarray and identified 46 genes that may play an important role in the progression of liver metastasis in CRC. Keywords: gene expression profiling using cDNA microarray
Project description:Recently a consensus molecular subtype (CMS) classification of colorectal cancer (CRC) has been established that is based on the transcriptional rather than the genetic profile of an individual tumor and which may ultimately help to individualize CRC therapy. So far, however, the lack of appropriate animal models that faithfully recapitulate the different molecular subtypes impedes adequate preclinical testing of stratified therapeutic concepts. Here we demonstrate that constitutive AKT activation in intestinal epithelial cells markedly enhances colonic tumor invasion and metastasis in Trp53DIEC mice (Trp53ΔIECAktE17K) upon challenge with the carcinogen azoxymethane (AOM). Gene-expression profiling indicates that Trp53ΔIECAktE17K tumors closely resemble the human mesenchymal colorectal cancer subtype (CMS4), which is characterized by the poorest survival rate among the four consensus molecular subtypes of CRC. Trp53ΔIECAktE17K tumors are further characterized by a NOTCH pathway gene signature and a distinct cell autonomous upregulation of Notch3 in tumor epithelia while treatment of Trp53ΔIECAktE17K mice with a NOTCH3-inhibiting antibody reduces invasion and metastasis. Conversely, selective activation of NOTCH3 by overexpression of NOTCH3-IC in Akt wt tumor organoids strongly promotes development of metastasis in an orthotopic transplantation model. In CRC patients NOTCH3 expression correlates positively with tumor grading and the presence of lymph node as well as distant metastases and is specifically upregulated in CMS4 tumors. Therefore, we suggest NOTCH3 as a putative target for advanced CMS4 CRC patients.
Project description:Identification of differentially expressed microRNAs in Colorectal Cancer Distant metastasis is the major determinant of patient outcome in colorectal cancer and microRNAs have emerged as an increasingly important class of molecules which can regulate several steps of the metastatic cascade. By systematically analysing the miR expression profiles of resected metastasis-, corresponding primary tumor- and normal tissues of colorectal cancer patients, we were able to delineate a miR-signature indicative of the metastatically critical microRNA landscape. 9 colorectal cancer patients were profiled comprising 5 patients with tissues from the primary tumor, normal mucosa, secondary metastasis and the background tissue in which the metastasis ocurred. In the remaining 4 patients, one of these four tissue entitities is missing. One patient had two synchronous primary tumors, one in the colon and the other in the rectum.
Project description:The purpose of this study is to identify miRNAs involved in the pathology of colorectal cancer (CRC) liver metastasis and investigate their underlying mechanisms. A total of 39 miRNAs were identified to be differentially expressed between 16 primary CRC tissues with liver metastases and 16 CRC tissues without liver metastases from 32 patients by Affymetric miRNA microarrays. 16 coloretcal cancer tissues with liver metastasis and 16 colorectal cancer tissues without liver metastasis were included in this study for RNA extraction and hybridization on Affymetrix microarrays. We sought to identify the differentially expressed miRNAs between colorectal cancer tissues with and without liver metastasis.
Project description:Identifying the exact molecules associated with CRC metastasis may be crucial to understand the process, which might also be translated to the diagnosis and treatment of CRC. In this study, we investigate the association of microRNA expression patterns with the lymph node metastasis of colorectal cancer. To investigate the association of microRNA expression patterns with the lymph node metastasis of colorectal cancer, eight primary colorectal cancer tissues derived from stage II–III colorectal cancer patients with (n = 4) or without (n = 4) lymph node metastasis were collected and the miRNA expression profiles of them were determined using Agilent miRNA microarray. Different miRNA expression profiles were identified in CRC tissues between lymph node metastasis positive and negative group.
Project description:Paired tissues (normal colon, primary colorectal carcinoma, normal liver, liver metastasis of colorectal carcinoma) from 2 colorectal carcinoma patients in Taiwan were processed to generate total RNA, which was subsequently analyzed for gene expression using Affymetrix U133 plus 2.0 arrays. Comparison of gene expression profiles between paired normal colon and primary colorectal carcinoma; between primary colorectal carcinoma and liver metastasis colorectal carcinoma
Project description:To identify the lymph node (LN) metastasis-associated genes in primary ESCC tumors, gene expression profiling assay (GEP) was performed to identify the differences in gene expression profiles between primary ESCC tumors that were with LN metastases (N+) and those without LN metastases (N-).
Project description:We identify genes presenting a specific expression profile in midgut carcinoid cells, primary carcinoids tumors and liver metastasis were gene profiled. Gene expression profiling of classical midgut carcinoid primary tumors and liver metastasis reveal potential novel therapeutic targets and molecular signatures. Experiment Overall Design: Normal and tumoral (carcinoid) cells