Unknown,Transcriptomics,Genomics,Proteomics

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A comparison of DNA copy number profiling platforms using a panel of melanoma cell lines

ABSTRACT: The accurate mapping of recurring DNA copy number aberrations (CNAs), a hallmark feature of the cancer genome, has facilitated the discovery of tumor suppressor genes and oncogenes. Microarray-based assays designed to detect these chromosomal copy number alterations on a genome-wide and high-resolution scale have emerged as a cornerstone technology in the genomic era. The diversity of commercially-available platforms prompted a systematic comparison of five copy number profiling assays for their ability to detect 2-fold copy number gain and loss (4n or 1n, respectively) as well as focal high-amplitude CNAs. Here, using a collection of established human melanoma cell lines, we defined the reproducibility, absolute signals, signal:noise, false-positive and false-negative rates for each of the five assays against ground-truth defined by Spectral Karyotyping (SKY), in addition to comparing the concordance of CNAs detection by two high-resolution Agilent and Affymetrix microarray platforms. Our analyses concluded that the Agilentâs 60mer oligo-microarray with probe design optimized for genomic hybridization offers the highest sensitivity and specificity [area under Receiver Operator Characteristic (ROC) curve >0.99] while Affymetrixâs SNP microarray appears to offer better detection of CNAs in gene-poor region. Availability of these comparison results should guide study design decisions and facilitate further computational development. Keywords: comparative genomic hybridization We generated copy number profiles of a defined set of tumor cell lines on five oligo-microarray-based assays of three platforms (Agilent, Affymetrix and NimbleGen) and determined the reproducibility, signal and noise as well as sensitivity and specificity of each in detecting two-fold signals based on SKY-defined aberrations as ground-truth for comparison. In addition, high-density microarray assays from Agilent and Affymetrix platforms were further compared for definition of CNAs in an independent dataset using published analytical approaches. All arrays were run from the same DNA harvest from respective cell lines. Each array was run according to the protocol of the manufacturer.

ORGANISM(S): Homo sapiens

SUBMITTER: Joel Greshock

PROVIDER: E-GEOD-7822 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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A comparison of DNA copy number profiling platforms.

Greshock Joel J Feng Bin B Nogueira Cristina C Ivanova Elena E Perna Ilana I Nathanson Katherine K Protopopov Alexei A Weber Barbara L BL Chin Lynda L

Cancer research 20071029 21

The accurate mapping of recurring DNA copy number aberrations (CNAs), a hallmark feature of the cancer genome, has facilitated the discovery of tumor suppressor genes and oncogenes. Microarray-based assays designed to detect these chromosomal copy number alterations on a genome-wide and high-resolution scale have emerged as a cornerstone technology in the genomic era. The diversity of commercially available platforms prompted a systematic comparison of five copy number profiling assays for their ...[more]

PMID: 17968032

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Project description:Primitive neuro-ectodermal tumours (PNET) of the supratentorial region are rare, highly malignant embryonal brain tumours affecting young children. Although supratentorial PNET (sPNET) are histologically similar to infratentorial PNET/medulloblastoma, sPNET have more aggressive clinical phenotypes, which suggest sPNET represents distinct biological entities. In contrast to considerable progress in understanding the signalling pathways involved in medulloblastoma, little is known about sPNET pathogenesis. Prior low resolution CGH (comparative genomic hybridization) studies indicate sPNET have frequent genomic imbalances and copy number aberrations (CNAs). To define genes involved in sPNET pathogenesis, we utilized the Affymetrix 250K Nsp SNP (single nucleotide polymorphism) analysis to identify genes targeted by recurrent CNAs in primary human sPNET samples. Copy number analysis was conducted on 39 primary PNET samples. Select target genes were validated by genomic and/or RT-PCR. Our analysis revealed frequent CNA across the sPNET genome, encompassing large and focal chromosome segments, and corroborated previous reports that isochromosome 17q, an abnormality found in ~ 30% of medulloblastoma, is rare in sPNET. Keywords: single nucleotide polymorphism array, disease state analysis A total of 56 primary sPNET samples were collected for this study from The Hospital for Sick Children, John Hopkins University, St. Jude Research Hospital, University of Cambridge, Children’s Hospital Boston, Virginia Commonwealth University, Instituto nazionale per lo studio e la cura dei tumori, and Texas Children’s Hospital, with local Institutional Research Ethics Board approval. Pineoblastoma and rhaboid tumours were specifically excluded, leaving 52 samples, 39 of which had good quality DNA available. These samples, in addition to 28 diploid reference samples (a gift from Dr. S. Scherer, University of Toronto), were analyzed on the Affymetrix GeneChip Mapping 250K Nsp SNP array. Due to sample availability at the time the arrays were run, the diploid reference samples analyzed on the Sty arrays are different from reference samples analyzed on the Nsp arrays.

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A comparison of DNA copy number profiling platforms using a panel of melanoma cell lines

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A comparison of DNA copy number profiling platforms.

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