Dynamics of genome alterations in Crohn’s disease associated colorectal carcinogenesis
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE113015 | GEO | 2018/06/30
REPOSITORIES: GEO
Similar Datasets
Project description:Human colorectal cancer (CRC) is one of the better-understood systems for studying the genetics of cancer initiation and progression. To develop a cross-species comparison strategy for identifying CRC causative gene or genomic alterations, we performed array comparative genomic hybridization (aCGH) to investigate copy number abnormalities (CNAs), one of the most prominent lesion types reported for human CRCs, in 10 spontaneously occurring canine CRCs. The results revealed for the first time a strong degree of genetic homology between sporadic canine and human CRCs. First, we saw that between 5 and 22% of the canine genome was amplified/deleted in these tumors, and that, reminiscent of human CRCs, the total altered sequences directly correlated to the tumorâs progression stage, origin, and likely microsatellite instability status. Second, when mapping the identified CNAs onto syntenic regions of the human genome, we noted that the canine orthologs of genes participating in known human CRC pathways were recurrently disrupted, indicating that these pathways might be altered in the canine CRCs as well. Lastly, we observed a significant overlapping of CNAs between human and canine tumors, and tumors from the two species were clustered according to the tumor subtypes but not the species. Significantly, compared with the shared CNAs, we found that species-specific (especially human-specific) CNAs localize to evolutionarily unstable regions that harbor more segmental duplications and interspecies genomic rearrangement breakpoints. These findings indicate that CNAs recurrent between human and dog CRCs may have a higher probability of being cancer-causative, compared with CNAs found in one species only Comparison of human and dog colon cancer CNAs
2010-05-15 | E-GEOD-19318 | biostudies-arrayexpress
Project description:Purpose: Small bowel adenocarcinoma (SBA) is a rare cancer and consequently the number of clinical trials has been very limited due to the small numbers of patients. Chemotherapy regimens are currently rather arbitrarily chosen between either a colorectal (CRC) or a gastric cancer (GC) regimen. Chromosomal copy number aberrations are a hallmark of solid tumours and can be measured by array comparative genomic hybridization (aCGH). The aim of the present study is to investigate whether genome-wide copy number aberrations of SBA are more similar to CRC or GC in order to support treatment of SBA according to either regimen. Experimental Design: A total of 85 GCs, CRCs and SBAs were selected from existing in house aCGH datasets based on array quality and clinical parameters. Differences and similarities in gains and losses of the three tumor types were analyzed using supervised and unsupervised analysis. Results: Hierarchical clustering revealed substantial overlap of chromosomal copy number profiles between SBA and CRC and less overlap between SBA and GC. Chromosome 13q13.2-q31.3 is primarily gained in SBA and CRC and the strongest feature discriminating SBA from GC. Further strong discriminating copy number characteristics are aberrations at chromosomes 1p36.3-p34.3, 4p15.3-q35.2, 9p24.3-p11.1 and 17p13.3-p13.2. Conclusions: SBA is more similar to CRC than to GC, based on genome-wide copy number aberrations. These data provide molecular support for treatment of SBA according to a CRC regimen. 29 gastric adenocarcinomas on 5K or 6K BAC arrays of which 2 samples are also done on 30K oligonucleotide arrays as control samples, 29 colorectal adenocarcinomas on 5K or 6K BAC arrays of which 2 samples are also done on 30K oligonucleotide arrays as control, 27 small bowel adenocarcinomas done on 30K oligonucleotide arrays of which 2 samples are also done on 5K BAC arrays as control.
2011-06-13 | E-GEOD-23418 | biostudies-arrayexpress
Project description:Purpose: Small bowel adenocarcinoma (SBA) is a rare cancer and consequently the number of clinical trials has been very limited due to the small numbers of patients. Chemotherapy regimens are currently rather arbitrarily chosen between either a colorectal (CRC) or a gastric cancer (GC) regimen. Chromosomal copy number aberrations are a hallmark of solid tumours and can be measured by array comparative genomic hybridization (aCGH). The aim of the present study is to investigate whether genome-wide copy number aberrations of SBA are more similar to CRC or GC in order to support treatment of SBA according to either regimen. Experimental Design: A total of 85 GCs, CRCs and SBAs were selected from existing in house aCGH datasets based on array quality and clinical parameters. Differences and similarities in gains and losses of the three tumor types were analyzed using supervised and unsupervised analysis. Results: Hierarchical clustering revealed substantial overlap of chromosomal copy number profiles between SBA and CRC and less overlap between SBA and GC. Chromosome 13q13.2-q31.3 is primarily gained in SBA and CRC and the strongest feature discriminating SBA from GC. Further strong discriminating copy number characteristics are aberrations at chromosomes 1p36.3-p34.3, 4p15.3-q35.2, 9p24.3-p11.1 and 17p13.3-p13.2. Conclusions: SBA is more similar to CRC than to GC, based on genome-wide copy number aberrations. These data provide molecular support for treatment of SBA according to a CRC regimen.
2011-06-13 | GSE23418 | GEO
Project description:Human colorectal cancer (CRC) is one of the better-understood systems for studying the genetics of cancer initiation and progression. To develop a cross-species comparison strategy for identifying CRC causative gene or genomic alterations, we performed array comparative genomic hybridization (aCGH) to investigate copy number abnormalities (CNAs), one of the most prominent lesion types reported for human CRCs, in 10 spontaneously occurring canine CRCs. The results revealed for the first time a strong degree of genetic homology between sporadic canine and human CRCs. First, we saw that between 5 and 22% of the canine genome was amplified/deleted in these tumors, and that, reminiscent of human CRCs, the total altered sequences directly correlated to the tumor’s progression stage, origin, and likely microsatellite instability status. Second, when mapping the identified CNAs onto syntenic regions of the human genome, we noted that the canine orthologs of genes participating in known human CRC pathways were recurrently disrupted, indicating that these pathways might be altered in the canine CRCs as well. Lastly, we observed a significant overlapping of CNAs between human and canine tumors, and tumors from the two species were clustered according to the tumor subtypes but not the species. Significantly, compared with the shared CNAs, we found that species-specific (especially human-specific) CNAs localize to evolutionarily unstable regions that harbor more segmental duplications and interspecies genomic rearrangement breakpoints. These findings indicate that CNAs recurrent between human and dog CRCs may have a higher probability of being cancer-causative, compared with CNAs found in one species only
2010-01-19 | GSE19318 | GEO
Project description:Gene expression profiling has discriminated between sporadic microsatellite instable (MSI) and microsatellite stable (MSS) colorectal cancers (CRCs), whereas the expression pattern of familial colorectal cancer type X (FCCTX) and Lynch syndrome (LS) associated CRCs remain largely unknown. The purpose of this study is to use gene expression profiling of formalin-fixed paraffin-embedded (FFPE) tumor specimens from FCCTX, LS and sporadic CRC as a control to detect expression patterns and to identify signaling pathways differing between FCCTX and LS tumors. RNA extracted from 132 FFPE specimens (40 FCCTX, 42 LS, 50 sporadic) were profiled for differential gene expression by the whole genome cDNA-mediated annealing, selection, extension, and ligation (WG-DASL) assay containing 18626 genes.
2012-03-08 | E-GEOD-36335 | biostudies-arrayexpress
Project description:Gene expression profiling has discriminated between sporadic microsatellite instable (MSI) and microsatellite stable (MSS) colorectal cancers (CRCs), whereas the expression pattern of familial colorectal cancer type X (FCCTX) and Lynch syndrome (LS) associated CRCs remain largely unknown. The purpose of this study is to use gene expression profiling of formalin-fixed paraffin-embedded (FFPE) tumor specimens from FCCTX, LS and sporadic CRC as a control to detect expression patterns and to identify signaling pathways differing between FCCTX and LS tumors.
2012-03-08 | GSE36335 | GEO
Project description:Genomic instability, including microsatellite instability (MSI) and gross chromosomal abnormalities, has been described in sporadic colorectal cancer (CRC) and MSI has been suggested to have prognostic significance. However, there are few prognostically relevant biomarkers. Here we explore the potential of the analysis of DNA copy number changes at 1Mb resolution to predict survivorship in sporadic CRC. Keywords: Comparative Genomic Hybridization
2010-02-11 | GSE12520 | GEO
Project description:Background: Since there is a predilection of some clinical and molecular features for a given tumor location, we assessed whether this can be confirmed in late-onset colorectal cancer (LOCRC). Methods: We analyzed clinical and molecular characteristics of LOCRC at different tumor locations in order to determine if there are differential phenotypes related with the location in the colon. Results: Right colon cancers showed features associated with sporadic Microsatellite Instability: predominance of female cases and BRAF mutations, and an important mucinous component. Left colon cancers developed a higher number of polyps and multiple primary CRCs, showed the strongest familial component, and had better prognosis. Rectal cancers showed a predominantly sporadic phenotype, with worse prognosis and a CpG Island Methylator Phenotype (CIMP)-High. No copy number alterations (CNAs) greater than or equal to 50% were observed in this LOCRC group, and the most recurrent alterations were losses at 5q13 and 14q11, and gains at 7q11, 7q21-q22, 19p13-p12, 19q13 and 20p11-q11. KRAS and PIK3CA were the only mutated genes showing differences according to the tumor location, mainly for right colon cancers. Conclusions: Categorizing LOCRC according to tumor location appears to be an adequate first step to resolving the heterogeneity of this subset of CRC.
2019-12-20 | GSE108166 | GEO
Project description:To evaluate the mechanisms and consequences of chromosomal aberrations in colorectal cancer (CRC), we used a combination of spectral karyotyping, array comparative genomic hybridization (aCGH), and array-based global gene expression profiling on 31 primary carcinomas and 15 established cell lines. Importantly, aCGH showed that the genomic profiles of primary tumors are recapitulated in the cell lines. We revealed a preponderance of chromosome breakpoints at sites of copy number variants (CNVs) in the CRC cell lines, a novel mechanism of DNA breakage in cancer. The integration of gene expression and aCGH led to the identification of 157 genes localized within high-level copy number changes whose transcriptional deregulation was significantly affected across all of the samples, thereby suggesting that these genes play a functional role in CRC. Genomic amplification at 8q24 was the most recurrent event and led to the overexpression of MYC and FAM84B. Copy number dependent gene expression resulted in deregulation of known cancer genes such as APC, FGFR2, and ERBB2. The identification of only 36 genes whose localization near a breakpoint could account for their observed deregulated expression demonstrates that the major mechanism for transcriptional deregulation in CRC is genomic copy number changes resulting from chromosomal aberrations.
2019-02-05 | GSE126053 | GEO
Project description:<p>Lynch Syndrome (LS) tumors are characterized by constitutional mutations in DNA mismatch-repair genes. Colorectal cancers (CRCs) are the predominant tumor type in patients with LS. Here, we have used whole-genome and transcriptome sequencing of LS- CRC to find similarities and differences of mutation and gene expression characteristics between LS-CRC and sporadic CRC (data provided by <a href="./study.cgi?study_id=phs000178">TCGA via dbGaP</a>). Furthermore, we were interested in the molecular heterogeneity of LS-CRC. We have performed a molecular characterization of LS-tumors and of matched tumor-distant reference colonic mucosa based on whole-genome DNA- and RNA-sequencing analyses. Our data indicates the existence of two subgroups of LS-CRCs, G1 and G2, where G1 tumors show a higher number of somatic mutations, higher microsatellite slippage and a different mutation spectrum.</p>
| phs001407 | dbGaP