Project description:Genomic copy number aberrations of 11 gastric cancer cell lines were analyzed by 244k CGH array from Agilent Technologies. Based on this results, we separated the 11 cell lines into 2 groups, with and without copy number increase at chromosome 20q13
Project description:This study aims to stratify stage II and III colon cancer patients for risk of disease recurrence based on DNA aberrations, including DNA copy number aberrations (CNA) and CNA-associated chromosomal breakpoints. To this end, high quality array-CGH data of clinically well-annotated colon cancer specimens was generated using FFPE material from a selected series of primary tumor and patient-matched normal tissue.
Project description:Our aim is to identify frequent genomic aberrations both in ESCC and esophageal dysplasia, and to discover important copy number-driving genes and microRNAs in ESCC. We carried out array-based comparative genomic hybridization (array CGH) on 59 ESCC resection samples and 16 dysplasia biopsy samples. Expression of genes at 11q13.3 was analyzed by real-time PCR and immunohistochemistry (IHC). Integrated analysis was performed to identify genes or microRNAs with copy number-expression correlations.
Project description:In current study, we applied array-CGH analysis to detect somatic copy number aberrations across tumor genome to help separate multiple primary lung cancers from metastasis cancers.
Project description:DNA hypomethylation could lead to activation of alternate promoters in GBM. We profiled DNA methylation and H3K4me3 genome-wide, and also performed expression and copy number analysis on the same samples In this dataset, we include all array CGH copy number data obtained for five GBMs. We used estimated copy number to normalize sequencing-based methylation data.
Project description:Gene amplifications and deletions frequently contribute to tumorigenesis. Characterization of these DNA copy-number changes is important for both the basic understanding of cancer and its diagnosis. Comparative genomic hybridization (CGH) was developed to survey DNA copy-number variations across a whole genome. With CGH, differentially labelled test and reference genomic DNAs are co-hybridized to normal metaphase chromosomes, and fluorescence ratios along the length of chromosomes provide a cytogenetic representation of DNA copy-number variation. CGH, however, has a limited ( approximately 20 Mb) mapping resolution, and higher-resolution techniques, such as fluorescence in situ hybridization (FISH), are prohibitively labour-intensive on a genomic scale. Array-based CGH, in which fluorescence ratios at arrayed DNA elements provide a locus-by-locus measure of DNA copy-number variation, represents another means of achieving increased mapping resolution. Published array CGH methods have relied on large genomic clone (for example BAC) array targets and have covered only a small fraction of the human genome. cDNAs representing over 30,000 radiation-hybrid (RH)-mapped human genes provide an alternative and readily available genomic resource for mapping DNA copy-number changes. Although cDNA microarrays have been used extensively to characterize variation in human gene expression, human genomic DNA is a far more complex mixture than the mRNA representation of human cells. Therefore, analysis of DNA copy-number variation using cDNA microarrays would require a sensitivity of detection an order of magnitude greater than has been routinely reported. We describe here a cDNA microarray-based CGH method, and its application to DNA copy-number variation analysis in breast cancer cell lines and tumours. This study is described more fully in Pollack JR et al.(1999) Nat Genet 23:41-6 Keywords: other
Project description:Abnormalities in DNA copy number are frequently found in patients with multiple anomaly syndromes and mental retardation. Array-CGH is a high resolution whole-genome technology which improves detection of submicroscopic aberrations underlying these syndromes. Eight patients with mental disability, multiple congenital anomalies and dysmorphic features were screened for submicroscopic chromosomal imbalances using the GenoSensor Array 300 Chip. Subtelomeric aberrations previously detected by FISH analysis were confirmed in two patients, and accurate diagnosis was provided in two previously undiagnosed complex cases. Microdeletions at 15q11.2-q13 in a newborn with hypotonia, cryptorchidsm and hypopigmentation were detected with few discrepancies between the array results and FISH analysis. Contiguous microdeletion of GSCL, HIRA and TBX1 genes at 22q11.2 was identified in a previously undiagnosed boy with an unusual presentation of the VCF/DiGeorge spectrum. In a newborn with aniridia, a borderline false negative WT1 deletion was observed, most probably because of differences between the size of the genomic deletion and the microarray probe. A false positive rate of 0.2% was calculated for clone-by-clone analysis, while the per patient false positive rate was 20%. Array-based CGH is a powerful tool for the rapid and accurate detection of genetic disorders associated with copy number abnormalities, and can significantly improve clinical genetic diagnosis and care. Keywords: comparative genome hybridization (CGH)
Project description:Whole-genome screening of DNA-copy number changes by array-based or matrix comparative genomic hybridization (matrix-CGH). Keywords: Repeat sample.
Project description:Background/Aims: Microarray-based comparative genomic hybridisation (CGH) has allowed high-resolution analysis of DNA copy number alterations across the entire cancer genome. Recent advances in bioinformatics tools enable us to perform a robust and highly sensitive analysis of array CGH data and facilitate the discovery of novel cancer-related genes. Methods: We analysed a total of 29 pancreatic ductal adenocarcinoma (PDAC) samples (six cell lines and 23 microdissected tissue specimens) using 1 Mb-spaced CGH arrays. The transcript levels of all genes within the identified regions of genetic alterations were then screened using our Pancreatic Expression Database. Results: In addition to 238 high-level amplifications and 35 homozygous deletions, we identified 315 minimal common regions of “non-random” genetic alterations (115 gains and 200 losses) which were consistently observed across our tumour samples. The small size of these aberrations (median size of 880 kb) contributed to the reduced number of candidate genes included (on average 12 Ensembl-annotated genes). The database has further specified the genes whose expression levels are consistent with their copy number status. Such genes were UQCRB, SQLE, DDEF1, SLA, ERICH1 and DLC1, indicating that these may be potential target candidates within regions of aberrations. Conclusion: This study has revealed multiple novel regions that may indicate the locations of oncogenes or tumour suppressor genes in PDAC. Using the database, we provide a list of novel target genes whose altered DNA copy numbers could lead to significant changes in transcript levels in PDAC. (Harada et al. Pancreatology) Keywords: pancreatic ductal adenocarcinima, tissue microdissection, array CGH, genetic alterations