Homo sapiens
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ABSTRACT:
PROVIDER: PRJNA111019 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Co-amplification at chromosomes 8p11-8p12 and 11q12-11q14 occurs often in breast tumors, suggesting possible cooperation between genes in these regions in oncogenesis. We used high resolution array comparative genomic hybridization (array CGH) to map the minimal amplified regions. The 8p and 11q amplicons are complex and consist of at least four amplicon cores at each site. Candidate genes mapping to these regions were identified by combining copy number and RNA and protein expression analyses. Funcational analysis for transformation was further carried out with candidate genes to determine candidate oncogenes.
2009-09-02 | GSE12761 | GEO
Project description:Co-amplification at chromosomes 8p11-8p12 and 11q12-11q14 occurs often in breast tumors, suggesting possible cooperation between genes in these regions in oncogenesis. We used high resolution array comparative genomic hybridization (array CGH) to map the minimal amplified regions. The 8p and 11q amplicons are complex and consist of at least four amplicon cores at each site. Candidate genes mapping to these regions were identified by combining copy number and RNA and protein expression analyses. Funcational analysis for transformation was further carried out with candidate genes to determine candidate oncogenes. Near tiling path coverage of 8p11q array CGH experiments with breast cell lines and ductal invasive and lymph node-negative breast tumors.
2009-09-02 | E-GEOD-12761 | biostudies-arrayexpress
Project description:We developed a novel approach to isolate tumor cells with high purity from blood via immunomagnetic enrichment followed by fluorescence activated cell sorting (IE/FACS) and examined copy number alterations in these cells. Magnetic beads coated with EpCAM mAb were added to blood to enrich for tumor cells. Enriched samples were then subjected to FACS analysis using differentially labeled mAbs to distinguish tumor cells (EpCAM+) from leukocytes (CD45+) during sorting. DNA from isolated tumor cells was subjected to whole genome amplification (WGA) and copy number analysis via array comparative genomic hybridization (CGH). The assay was evaluated using BT474 and MCF7 breast cancer cell lines and in CTCs from 5 metastatic breast cancer (MBC) patients with matched archival primary tumors and later extended to an additional 97 MBC patients. Evaluation of the assay on isolated breast cancer cell lines spiked into blood correctly identified the known genomic alterations with high reproducibility. In clinical studies, comparison of CTCs with matched archival primary tumors confirmed shared lineage with notable divergence. In addition, serial testing of CTCs confirmed reproducibility, and indicated genomic change over time. Analysis of genomic profiles of CTCs from 102 MBC patients revealed common copy number alterations including gains in 1q and 8q and losses in 8p and 11q. Comparison with a published CGH dataset of primary breast tumors revealed similar frequencies of recurrent genomic copy number aberrations.
2012-12-31 | E-GEOD-27511 | biostudies-arrayexpress
Project description:Background: The amplification event occurring at chromosome locus 11q13, reported in several different cancers, includes a number of potential oncogenes. We have previously reported amplification of one such oncogene, CCND1, to be correlated with an adverse effect of tamoxifen in premenopausal breast cancer patients. Overexpression of cyclin D1 protein however, confers tamoxifen resistance but not a tamoxifen induced adverse effect. Potentially, co-amplification of an additional 11q13 gene, with a resulting protein overexpression, is required to cause an agonistic effect. Moreover, during 11q13 amplification a deletion of the distal 11q region has been described. In order to assess the potential impact of the deletion we have examined a selected marker for this event. Methods: Array CGH analysis was employed to identify and confirm changes in the gene expression of a number of different genes mapping to the 11q chromosomal region, associated with CCND1 amplification. The subsequent protein expression of these candidate genes was then examined in a clinical material of 500 primary breast cancers from premenopausal patients randomized to either tamoxifen or no adjuvant treatment. The protein expression was also compared to the CGH data in a subset of 56 breast cancer samples. Results: Cortactin and FADD overexpression was linked to CCND1 amplification, determined by FISH, but was not associated with a diminished effect of tamoxifen. However, deletion of distal chromosome 11q, defined as downregulation of the marker Chk1, was associated with an impaired tamoxifen response, and interestingly, also with low proliferative breast cancer of low grade. For Pak1 and cyclin D1 the protein expression corresponded to the gene expression data from the CGH analysis. Conclusions: The results indicate that many 11q13 associated gene products are overexpressed in conjunction with cyclin D1 but not linked to an agonistic effect of tamoxifen. Finally, the deletion of distal 11q, linked to 11q13 amplification, might be an important event affecting breast cancer outcome and tamoxifen response. Keywords: comparative genomic hybridisation
2008-10-08 | GSE12759 | GEO
Project description:HER2 gene amplification and protein overexpression (HER2+) define a clinically challenging subgroup of breast cancer with variable prognosis and response to therapy. Although gene expression profiling has identified an ERBB2 molecular subtype of breast cancer, it is clear that HER2+ tumors reside in all molecular subtypes and represent a genomically and biologically heterogeneous group. Genome-wide DNA copy number profiling, using BAC array comparative genomic hybridization (aCGH) were performed on 200 tumors with mixed clinical characteristics and amplification of HER2. Genomic Identification of Significant Targets in Cancer (GISTIC) was used to identify significant copy number aberrations (CNAs) in HER2+ tumors. This analysis sheds further light on the genomically complex and heterogeneous nature of HER2+ tumors in relation to other subgroups of breast cancer.
2010-04-14 | GSE21259 | GEO
Project description:Background: The amplification event occurring at chromosome locus 11q13, reported in several different cancers, includes a number of potential oncogenes. We have previously reported amplification of one such oncogene, CCND1, to be correlated with an adverse effect of tamoxifen in premenopausal breast cancer patients. Overexpression of cyclin D1 protein however, confers tamoxifen resistance but not a tamoxifen induced adverse effect. Potentially, co-amplification of an additional 11q13 gene, with a resulting protein overexpression, is required to cause an agonistic effect. Moreover, during 11q13 amplification a deletion of the distal 11q region has been described. In order to assess the potential impact of the deletion we have examined a selected marker for this event. Methods: Array CGH analysis was employed to identify and confirm changes in the gene expression of a number of different genes mapping to the 11q chromosomal region, associated with CCND1 amplification. The subsequent protein expression of these candidate genes was then examined in a clinical material of 500 primary breast cancers from premenopausal patients randomized to either tamoxifen or no adjuvant treatment. The protein expression was also compared to the CGH data in a subset of 56 breast cancer samples. Results: Cortactin and FADD overexpression was linked to CCND1 amplification, determined by FISH, but was not associated with a diminished effect of tamoxifen. However, deletion of distal chromosome 11q, defined as downregulation of the marker Chk1, was associated with an impaired tamoxifen response, and interestingly, also with low proliferative breast cancer of low grade. For Pak1 and cyclin D1 the protein expression corresponded to the gene expression data from the CGH analysis. Conclusions: The results indicate that many 11q13 associated gene products are overexpressed in conjunction with cyclin D1 but not linked to an agonistic effect of tamoxifen. Finally, the deletion of distal 11q, linked to 11q13 amplification, might be an important event affecting breast cancer outcome and tamoxifen response. Keywords: comparative genomic hybridisation 56 samples with 11q13 amplification have been analysed and compared with protein expression results from immunohistochemical analyses.
2008-10-07 | E-GEOD-12759 | biostudies-arrayexpress
Project description:Genomic changes in chromosome 8 are commonly observed in breast cancer cell lines and tumors. Fine mapping of such genomic changes, and evaluation of associated expression changes, are expected to provide reagents for diagnosis, insights into understanding the disease, and open up avenues for novel therapeutic intervention. We made an effort to search for genes on chromosome 8 with altered copy number and expression. A high resolution (0.1Mb) bacterial artificial chromosome (BAC) array of chromosome 8 that can detect single copy changes was developed using Phi29 DNA polymerase amplified BAC DNA. Hybridization of DNA from a breast cancer cell line (SKBR3) with two known amplified regions (8q21 and 8q24) resulted in resolving this region into 6 distinct amplicons, in addition identified 3 deleted regions. The boundaries and the peak of each region were verified by FISH, and the extent of amplification/deletion for each region was validated by qPCR. Using these BAC arrays, CGH was performed with a total of eight breast cancer cell lines, and common regions of genomic amplification/deletion were identified by segmentation analysis. Two consensus regions in 8q24 included a 1.2 Mb region (125.3-126.5 Mb) and a 1.0 Mb region (128.1-129.1 Mb) that were amplified in 7/8 cell lines, and in the 8q21 region there was a smaller 0.88 Mb region (86.62-87.50 Mb) amplified in 4/8 cell lines. A global expression analysis was performed for all these cell lines using a high-density oligonucleotide array to identify the genes whose expression correlated with amplification/deletion. Representative genes from 5 commonly amplified regions (REXO1L1, TMEM55A, TRMT12, MTSS1, EIF2C2, MYC) and 2 deleted regions (DPYSL2, NRG1 and NDRG1) were verified by qPCR and RT-qPCR for genomic and expression changes. Validation by RT-qPCR using RNA from 30 breast tumors showed that the TRMT12 (125.5 Mb) gene were overexpressed in many of the tumors. TRMT12 is homolog of a yeast gene encoding tRNA methyltransferase involved in biosythesis of a modified base in a tRNA. It would be interesting to explore the role of TRMT12 and the RNA processing pathway in tumorigenesis. Keywords: Comparative Genomic Hybridization (CGH), Breast cancer cell lines, Expression, BAC array, Oligo expression array
2007-05-07 | GSE6567 | GEO
Project description:To directly compare genomic alterations between patient tumors and derived cell lines, both parental tumors and cell lines were characterized by array-based comparative genomic hybridization.
2020-10-27 | GSE150963 | GEO
Project description:We developed a novel approach to isolate tumor cells with high purity from blood via immunomagnetic enrichment followed by fluorescence activated cell sorting (IE/FACS) and examined copy number alterations in these cells. Magnetic beads coated with EpCAM mAb were added to blood to enrich for tumor cells. Enriched samples were then subjected to FACS analysis using differentially labeled mAbs to distinguish tumor cells (EpCAM+) from leukocytes (CD45+) during sorting. DNA from isolated tumor cells was subjected to whole genome amplification (WGA) and copy number analysis via array comparative genomic hybridization (CGH). The assay was evaluated using BT474 and MCF7 breast cancer cell lines and in CTCs from 5 metastatic breast cancer (MBC) patients with matched archival primary tumors and later extended to an additional 97 MBC patients.
2012-12-31 | GSE27511 | GEO
Project description:BACKGROUND: Cervical carcinoma develops as a result of multiple genetic alterations. Different studies investigated genomic alterations in cervical cancer mainly by means of metaphase comparative genomic hybridization (mCGH) and microsatellite marker analysis for the detection of loss of heterozygosity (LOH). Currently, high throughput methods such as array comparative genomic hybridization (array CGH), single nucleotide polymorphism array (SNP array) and gene expression arrays are available to study genome-wide alterations. Integration of these 3 platforms allows detection of genomic alterations at high resolution and investigation of an association between copy number changes and expression. RESULTS: Genome-wide copy number and genotype analysis of 10 cervical cancer cell lines by array CGH and SNP array showed highly complex large-scale alterations. A comparison between array CGH and SNP array revealed that the overall concordance in detection of the same areas with copy number alterations (CNA) was above 90%. The use of SNP arrays demonstrated that about 75% of LOH events would not have been found by methods which screen for copy number changes, such as array CGH, since these were LOH events without CNA. Regions frequently targeted by CNA, as determined by array CGH, such as amplification of 5p and 20q, and loss of 8p were confirmed by fluorescent in situ hybridization (FISH). Genome-wide, we did not find a correlation between copy-number and gene expression. At chromosome arm 5p however, 22% of the genes were significantly upregulated in cell lines with amplifications as compared to cell lines without amplifications, as measured by gene expression arrays. For 3 genes, SKP2, ANKH and TRIO, expression differences were confirmed by quantitative real-time PCR (qRT-PCR). CONCLUSION: This study showed that copy number data retrieved from either array CGH or SNP array are comparable and that the integration of genome-wide LOH, copy number and gene expression is useful for the identification of gene specific targets that could be relevant for the development and progression in cervical cancer. Keywords: DNA copynumber RNA expression correlation
2007-07-31 | GSE8605 | GEO