Unknown,Transcriptomics,Genomics,Proteomics

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Frequent occurrence of deletions in primary mediastinal B-cell lymphoma

ABSTRACT: Primary mediastinal B-cell lymphoma (PMBCL) is a distinct subtype of diffuse large B-cell lymphoma. PMBCL has been previously studied with a variety of genomic techniques resulting in frequent detection of chromosomal gains; however, chromosomal losses have been rarely reported. This finding contrasts many other types of lymphoma, in which deletions are common. We hypothesize that segmental losses do exist but may have escaped detection by methods used in the previous studies. Using array comparative genomic hybridization to a tiling-resolution microarray encompassing the entire human genome, PMBCL samples were analyzed for genomic copy number alterations. Both gains and losses of chromosomal material were detected throughout the genome. These DNA copy number alterations were confirmed by quantitative real-time PCR. Recurrent chromosomal losses include a novel event at 1p13.1-p13.2 present in 42% of cases analyzed. We conclude that losses are present in the PMBCL genome. Given the similar frequency of losses to that of segmental gains of DNA, they are likely to play an important role in the pathogenesis of PMBCL. Whole genome tiling path array CGH of 20 PMBCL tumor samples and one cell line was performed against male reference genomic DNA. Alterations were confirmed via DNA copy number quantitative real-time PCR

ORGANISM(S): Homo sapiens

SUBMITTER: Lindsey Kimm

PROVIDER: E-GEOD-7383 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Frequent occurrence of deletions in primary mediastinal B-cell lymphoma.

Kimm Lindsey R LR deLeeuw Ronald J RJ Savage Kerry J KJ Rosenwald Andreas A Campo Elias E Delabie Jan J Ott German G Muller-Hermelink Hans-Konrad HK Jaffe Elaine S ES Rimsza Lisa M LM Weisenburger Dennis D DD Chan Wing C WC Staudt Louis M LM Connors Joseph M JM Gascoyne Randy D RD Lam Wan L WL

Genes, chromosomes & cancer 20071201 12

Primary mediastinal B-cell lymphoma (PMBCL) is a distinct subtype of diffuse large B-cell lymphoma. PMBCL has been previously studied with a variety of genomic techniques resulting in frequent detection of chromosomal gains; however, chromosomal losses have been rarely reported. This finding contrasts many other types of lymphoma, in which deletions are common. We hypothesize that segmental losses do exist but may have escaped detection by methods used in the previous studies. Using array compar ...[more]

PMID: 17823928

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Frequent occurrence of deletions in primary mediastinal B-cell lymphoma

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Frequent occurrence of deletions in primary mediastinal B-cell lymphoma.

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