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- Mertens, Fredrik, et al.
(författare)
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Clinicopathologic and molecular genetic characterization of low-grade fibromyxoid sarcoma, and cloning of a novel FUS/CREB3L1 fusion gene
- 2005
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Ingår i: Laboratory Investigation. - : Elsevier BV. - 1530-0307 .- 0023-6837. ; 85:3, s. 408-415
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Tidskriftsartikel (refereegranskat)abstract
- Low-grade fibromyxoid sarcoma (LGFMS) is an indolent, late-metastasizing malignant soft-tissue tumor that is often mistaken for either more benign or more malignant tumor types. Cytogenetic analyses have identified a recurrent balanced translocation t(7;16) (q32-34;p11), later shown by molecular genetic approaches to result in a FUS/CREB3L2 fusion gene. Whereas preliminary studies suggest that this gene rearrangement is specific for LGFMS, its incidence in this tumor type and the possible existence of variant fusion genes have not yet been addressed. For this purpose, a series of potential LGFMS were obtained from nine different soft-tissue tumor centres and subjected to molecular analysis as well as careful histopathologic review. Reverse transcriptase-polymerase chain reaction analysis disclosed a FUS/CREB3L2 fusion transcript in 22 of the 23 (96%) cases that remained classified as LGFMS after the histologic re-evaluation and from which RNA of sufficient quality could be extracted, whereas none of the cases that were classified as other tumor types was fusion-positive. In one of the tumors with typical LGFMS appearance, we found that FUS was fused to the CREB3L1 gene instead of CREB3L2. The proteins encoded by these genes both belong to the same basic leucine-zipper family of transcription factors, and display extensive sequence homology in their DNA-binding domains. Thus, it is expected that the novel FUS/CREB3L1 chimera will have a similar impact at the cellular level as the much more common FUS/CREB3L2 fusion protein. Taken together, the results indicate that virtually all LGFMS are characterized by a chimeric FUS/CREB3L2 gene, and that rare cases may display a variant FUS/CREB3L1 fusion.
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2. |
- Mertens, Fredrik, et al.
(författare)
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Prognostically important chromosomal aberrations in soft tissue sarcomas: a report of the Chromosomes and Morphology (CHAMP) Study Group.
- 2002
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Ingår i: Cancer Research. - 1538-7445. ; 62:14, s. 3980-3984
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Tidskriftsartikel (refereegranskat)abstract
- Cytogenetic analysis has not only provided important information on the pathogenesis of soft tissue tumors but, by disclosing distinct chromosomal rearrangements in different histopathological entities, has also come to serve as a valuable diagnostic tool. Little is known as yet about the potential prognostic impact of cytogenetic features detected in these tumors. A total of 239 benign and 221 malignant soft tissue tumors with clonal chromosome aberrations were subdivided according to general karyotypic features, such as degree of complexity and ploidy level, and rearrangements of specific chromosomal regions. The cytogenetic variables were analyzed regarding clinical outcome, using time to metastasis as the end point. Selected variables were then compared with established clinicopathological predictors of metastasis development. When the entire material was considered, 167 of 268 investigated cytogenetic variables were associated with clinical outcome. Focusing on the subset of 151 patients with high-grade sarcoma, 17 variables were identified that, besides grade and size, were associated with increased risk of metastasis development. A final Cox regression analysis identified five independent cytogenetic predictors of adverse outcome; breakpoints in chromosome regions 1p1, 1q4, 14q1, and 17q2, and gain of regions 6p1/p2. An increasing effect on metastatic risk was seen with increasing involvement of the selected cytogenetic variables, even when different histopathological types were studied separately. We conclude that cytogenetic data provide independent prognostic information in soft tissue sarcomas. Furthermore, our results point to specific areas of the genome harboring genes that may influence the metastatic potential of sarcoma cells.
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