6533b7d9fe1ef96bd126d79d

RESEARCH PRODUCT

Microarray mRNA expression analysis of Fanconi anemia fibroblasts.

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description

Fanconi anemia (FA) cells are generally hypersensitive to DNA cross-linking agents, implying that mutations in the different <i>FANC</i> genes cause a similar DNA repair defect(s). By using a customized cDNA microarray chip for DNA repair- and cell cycle-associated genes, we identified three genes, cathepsin B (<i>CTSB</i>), glutaredoxin (<i>GLRX</i>), and polo-like kinase 2 (<i>PLK2</i>), that were misregulated in untreated primary fibroblasts from three unrelated FA-D2 patients, compared to six controls. Quantitative real-time RT PCR was used to validate these results and to study possible molecular links between FA-D2 and other FA subtypes. <i>GLRX</i> was misregulated to opposite directions in a variety of different FA subtypes. Increased <i>CTSB</i> and decreased <i>PLK2</i> expression was found in all or almost all of the analyzed complementation groups and, therefore, may be related to the defective FA pathway. Transcriptional upregulation of the CTSB proteinase appears to be a secondary phenomenon due to proliferation differences between FA and normal fibroblast cultures. In contrast, <i>PLK2</i> is known to play a pivotal role in processes that are linked to FA defects and may contribute in multiple ways to the FA phenotype: <i>PLK2</i> is a target gene for <i>TP53</i>, is likely to function as a tumor suppressor gene in hematologic neoplasia, and <i>Plk2</i><sup>–/–</sup> mice are small because of defective embryonal development.